hlist: drop the node parameter from iterators
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / sysfs / bin.c
CommitLineData
1da177e4 1/*
6d66f5cd 2 * fs/sysfs/bin.c - sysfs binary file implementation
1da177e4
LT
3 *
4 * Copyright (c) 2003 Patrick Mochel
5 * Copyright (c) 2003 Matthew Wilcox
6 * Copyright (c) 2004 Silicon Graphics, Inc.
6d66f5cd
TH
7 * Copyright (c) 2007 SUSE Linux Products GmbH
8 * Copyright (c) 2007 Tejun Heo <teheo@suse.de>
9 *
10 * This file is released under the GPLv2.
11 *
12 * Please see Documentation/filesystems/sysfs.txt for more information.
1da177e4
LT
13 */
14
15#undef DEBUG
16
17#include <linux/errno.h>
18#include <linux/fs.h>
995982ca 19#include <linux/kernel.h>
1da177e4
LT
20#include <linux/kobject.h>
21#include <linux/module.h>
22#include <linux/slab.h>
869512ab 23#include <linux/mutex.h>
e0edd3c6 24#include <linux/mm.h>
1da177e4
LT
25
26#include <asm/uaccess.h>
27
28#include "sysfs.h"
29
e0edd3c6
EB
30/*
31 * There's one bin_buffer for each open file.
32 *
33 * filp->private_data points to bin_buffer and
34 * sysfs_dirent->s_bin_attr.buffers points to a the bin_buffer s
35 * sysfs_dirent->s_bin_attr.buffers is protected by sysfs_bin_lock
36 */
37static DEFINE_MUTEX(sysfs_bin_lock);
38
eb361653 39struct bin_buffer {
e0edd3c6
EB
40 struct mutex mutex;
41 void *buffer;
42 int mmapped;
f0f37e2f 43 const struct vm_operations_struct *vm_ops;
e0edd3c6
EB
44 struct file *file;
45 struct hlist_node list;
eb361653
TH
46};
47
1da177e4 48static int
2c3c8bea 49fill_read(struct file *file, char *buffer, loff_t off, size_t count)
1da177e4 50{
2c3c8bea 51 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61
TH
52 struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
53 struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088
TH
54 int rc;
55
56 /* need attr_sd for attr, its parent for kobj */
e72ceb8c 57 if (!sysfs_get_active(attr_sd))
0ab66088 58 return -ENODEV;
1da177e4 59
0ab66088
TH
60 rc = -EIO;
61 if (attr->read)
2c3c8bea 62 rc = attr->read(file, kobj, attr, buffer, off, count);
1da177e4 63
e72ceb8c 64 sysfs_put_active(attr_sd);
0ab66088
TH
65
66 return rc;
1da177e4
LT
67}
68
69static ssize_t
93e3cd82 70read(struct file *file, char __user *userbuf, size_t bytes, loff_t *off)
1da177e4 71{
eb361653 72 struct bin_buffer *bb = file->private_data;
496ad9aa 73 int size = file_inode(file)->i_size;
1da177e4 74 loff_t offs = *off;
93e3cd82 75 int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5 76 char *temp;
1da177e4 77
4503efd0
GKH
78 if (!bytes)
79 return 0;
80
1da177e4
LT
81 if (size) {
82 if (offs > size)
83 return 0;
84 if (offs + count > size)
85 count = size - offs;
86 }
87
b31ca3f5
NP
88 temp = kmalloc(count, GFP_KERNEL);
89 if (!temp)
90 return -ENOMEM;
91
eb361653
TH
92 mutex_lock(&bb->mutex);
93
2c3c8bea 94 count = fill_read(file, bb->buffer, offs, count);
b31ca3f5
NP
95 if (count < 0) {
96 mutex_unlock(&bb->mutex);
97 goto out_free;
98 }
1da177e4 99
b31ca3f5
NP
100 memcpy(temp, bb->buffer, count);
101
102 mutex_unlock(&bb->mutex);
103
104 if (copy_to_user(userbuf, temp, count)) {
eb361653 105 count = -EFAULT;
b31ca3f5 106 goto out_free;
eb361653 107 }
1da177e4 108
93e3cd82 109 pr_debug("offs = %lld, *off = %lld, count = %d\n", offs, *off, count);
1da177e4
LT
110
111 *off = offs + count;
112
b31ca3f5
NP
113 out_free:
114 kfree(temp);
1da177e4
LT
115 return count;
116}
117
118static int
2c3c8bea 119flush_write(struct file *file, char *buffer, loff_t offset, size_t count)
1da177e4 120{
2c3c8bea 121 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61
TH
122 struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
123 struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
0ab66088
TH
124 int rc;
125
126 /* need attr_sd for attr, its parent for kobj */
e72ceb8c 127 if (!sysfs_get_active(attr_sd))
0ab66088 128 return -ENODEV;
1da177e4 129
0ab66088
TH
130 rc = -EIO;
131 if (attr->write)
2c3c8bea 132 rc = attr->write(file, kobj, attr, buffer, offset, count);
1da177e4 133
e72ceb8c 134 sysfs_put_active(attr_sd);
0ab66088
TH
135
136 return rc;
1da177e4
LT
137}
138
93e3cd82
TH
139static ssize_t write(struct file *file, const char __user *userbuf,
140 size_t bytes, loff_t *off)
1da177e4 141{
eb361653 142 struct bin_buffer *bb = file->private_data;
496ad9aa 143 int size = file_inode(file)->i_size;
1da177e4 144 loff_t offs = *off;
93e3cd82 145 int count = min_t(size_t, bytes, PAGE_SIZE);
b31ca3f5 146 char *temp;
1da177e4 147
4503efd0
GKH
148 if (!bytes)
149 return 0;
150
1da177e4
LT
151 if (size) {
152 if (offs > size)
153 return 0;
154 if (offs + count > size)
155 count = size - offs;
156 }
157
1c8542c7
LZ
158 temp = memdup_user(userbuf, count);
159 if (IS_ERR(temp))
160 return PTR_ERR(temp);
1da177e4 161
b31ca3f5
NP
162 mutex_lock(&bb->mutex);
163
164 memcpy(bb->buffer, temp, count);
165
2c3c8bea 166 count = flush_write(file, bb->buffer, offs, count);
b31ca3f5
NP
167 mutex_unlock(&bb->mutex);
168
1da177e4
LT
169 if (count > 0)
170 *off = offs + count;
eb361653 171
d5ce5b40 172 kfree(temp);
1da177e4
LT
173 return count;
174}
175
e0edd3c6
EB
176static void bin_vma_open(struct vm_area_struct *vma)
177{
178 struct file *file = vma->vm_file;
179 struct bin_buffer *bb = file->private_data;
180 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
181
38f49a51 182 if (!bb->vm_ops)
e0edd3c6
EB
183 return;
184
e72ceb8c 185 if (!sysfs_get_active(attr_sd))
e0edd3c6
EB
186 return;
187
38f49a51
EB
188 if (bb->vm_ops->open)
189 bb->vm_ops->open(vma);
e0edd3c6 190
e72ceb8c 191 sysfs_put_active(attr_sd);
e0edd3c6
EB
192}
193
e0edd3c6
EB
194static int bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
195{
196 struct file *file = vma->vm_file;
197 struct bin_buffer *bb = file->private_data;
198 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
199 int ret;
200
38f49a51 201 if (!bb->vm_ops)
e0edd3c6
EB
202 return VM_FAULT_SIGBUS;
203
e72ceb8c 204 if (!sysfs_get_active(attr_sd))
e0edd3c6
EB
205 return VM_FAULT_SIGBUS;
206
38f49a51
EB
207 ret = VM_FAULT_SIGBUS;
208 if (bb->vm_ops->fault)
209 ret = bb->vm_ops->fault(vma, vmf);
e0edd3c6 210
e72ceb8c 211 sysfs_put_active(attr_sd);
e0edd3c6
EB
212 return ret;
213}
214
851a039c 215static int bin_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf)
e0edd3c6
EB
216{
217 struct file *file = vma->vm_file;
218 struct bin_buffer *bb = file->private_data;
219 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
220 int ret;
221
095160ae 222 if (!bb->vm_ops)
851a039c 223 return VM_FAULT_SIGBUS;
e0edd3c6 224
e72ceb8c 225 if (!sysfs_get_active(attr_sd))
851a039c 226 return VM_FAULT_SIGBUS;
e0edd3c6 227
38f49a51
EB
228 ret = 0;
229 if (bb->vm_ops->page_mkwrite)
230 ret = bb->vm_ops->page_mkwrite(vma, vmf);
14ae417c
JK
231 else
232 file_update_time(file);
e0edd3c6 233
e72ceb8c 234 sysfs_put_active(attr_sd);
e0edd3c6
EB
235 return ret;
236}
237
238static int bin_access(struct vm_area_struct *vma, unsigned long addr,
239 void *buf, int len, int write)
240{
241 struct file *file = vma->vm_file;
242 struct bin_buffer *bb = file->private_data;
243 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
244 int ret;
245
38f49a51 246 if (!bb->vm_ops)
e0edd3c6
EB
247 return -EINVAL;
248
e72ceb8c 249 if (!sysfs_get_active(attr_sd))
e0edd3c6
EB
250 return -EINVAL;
251
38f49a51
EB
252 ret = -EINVAL;
253 if (bb->vm_ops->access)
254 ret = bb->vm_ops->access(vma, addr, buf, len, write);
e0edd3c6 255
e72ceb8c 256 sysfs_put_active(attr_sd);
e0edd3c6
EB
257 return ret;
258}
259
095160ae
HD
260#ifdef CONFIG_NUMA
261static int bin_set_policy(struct vm_area_struct *vma, struct mempolicy *new)
262{
263 struct file *file = vma->vm_file;
264 struct bin_buffer *bb = file->private_data;
265 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
266 int ret;
267
38f49a51 268 if (!bb->vm_ops)
095160ae
HD
269 return 0;
270
e72ceb8c 271 if (!sysfs_get_active(attr_sd))
095160ae
HD
272 return -EINVAL;
273
38f49a51
EB
274 ret = 0;
275 if (bb->vm_ops->set_policy)
276 ret = bb->vm_ops->set_policy(vma, new);
095160ae 277
e72ceb8c 278 sysfs_put_active(attr_sd);
095160ae
HD
279 return ret;
280}
281
282static struct mempolicy *bin_get_policy(struct vm_area_struct *vma,
283 unsigned long addr)
284{
285 struct file *file = vma->vm_file;
286 struct bin_buffer *bb = file->private_data;
287 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
288 struct mempolicy *pol;
289
38f49a51 290 if (!bb->vm_ops)
095160ae
HD
291 return vma->vm_policy;
292
e72ceb8c 293 if (!sysfs_get_active(attr_sd))
095160ae
HD
294 return vma->vm_policy;
295
38f49a51
EB
296 pol = vma->vm_policy;
297 if (bb->vm_ops->get_policy)
298 pol = bb->vm_ops->get_policy(vma, addr);
095160ae 299
e72ceb8c 300 sysfs_put_active(attr_sd);
095160ae
HD
301 return pol;
302}
303
304static int bin_migrate(struct vm_area_struct *vma, const nodemask_t *from,
305 const nodemask_t *to, unsigned long flags)
306{
307 struct file *file = vma->vm_file;
308 struct bin_buffer *bb = file->private_data;
309 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
310 int ret;
311
38f49a51 312 if (!bb->vm_ops)
095160ae
HD
313 return 0;
314
e72ceb8c 315 if (!sysfs_get_active(attr_sd))
095160ae
HD
316 return 0;
317
38f49a51
EB
318 ret = 0;
319 if (bb->vm_ops->migrate)
320 ret = bb->vm_ops->migrate(vma, from, to, flags);
095160ae 321
e72ceb8c 322 sysfs_put_active(attr_sd);
095160ae
HD
323 return ret;
324}
325#endif
326
f0f37e2f 327static const struct vm_operations_struct bin_vm_ops = {
e0edd3c6 328 .open = bin_vma_open,
e0edd3c6
EB
329 .fault = bin_fault,
330 .page_mkwrite = bin_page_mkwrite,
331 .access = bin_access,
095160ae
HD
332#ifdef CONFIG_NUMA
333 .set_policy = bin_set_policy,
334 .get_policy = bin_get_policy,
335 .migrate = bin_migrate,
336#endif
e0edd3c6
EB
337};
338
1da177e4
LT
339static int mmap(struct file *file, struct vm_area_struct *vma)
340{
eb361653 341 struct bin_buffer *bb = file->private_data;
3e519038 342 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61
TH
343 struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
344 struct kobject *kobj = attr_sd->s_parent->s_dir.kobj;
eb361653 345 int rc;
1da177e4 346
eb361653 347 mutex_lock(&bb->mutex);
0ab66088
TH
348
349 /* need attr_sd for attr, its parent for kobj */
e0edd3c6 350 rc = -ENODEV;
e72ceb8c 351 if (!sysfs_get_active(attr_sd))
e0edd3c6 352 goto out_unlock;
0ab66088
TH
353
354 rc = -EINVAL;
e0edd3c6
EB
355 if (!attr->mmap)
356 goto out_put;
0ab66088 357
2c3c8bea 358 rc = attr->mmap(file, kobj, attr, vma);
e0edd3c6
EB
359 if (rc)
360 goto out_put;
0ab66088 361
095160ae
HD
362 /*
363 * PowerPC's pci_mmap of legacy_mem uses shmem_zero_setup()
364 * to satisfy versions of X which crash if the mmap fails: that
365 * substitutes a new vm_file, and we don't then want bin_vm_ops.
366 */
367 if (vma->vm_file != file)
e0edd3c6
EB
368 goto out_put;
369
e0edd3c6 370 rc = -EINVAL;
095160ae 371 if (bb->mmapped && bb->vm_ops != vma->vm_ops)
e0edd3c6 372 goto out_put;
e0edd3c6 373
a6849fa1
EB
374 /*
375 * It is not possible to successfully wrap close.
376 * So error if someone is trying to use close.
377 */
378 rc = -EINVAL;
379 if (vma->vm_ops && vma->vm_ops->close)
380 goto out_put;
381
e0edd3c6
EB
382 rc = 0;
383 bb->mmapped = 1;
095160ae
HD
384 bb->vm_ops = vma->vm_ops;
385 vma->vm_ops = &bin_vm_ops;
e0edd3c6 386out_put:
e72ceb8c 387 sysfs_put_active(attr_sd);
e0edd3c6 388out_unlock:
eb361653
TH
389 mutex_unlock(&bb->mutex);
390
391 return rc;
1da177e4
LT
392}
393
394static int open(struct inode * inode, struct file * file)
395{
3e519038 396 struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata;
b1fc3d61 397 struct bin_attribute *attr = attr_sd->s_bin_attr.bin_attr;
eb361653 398 struct bin_buffer *bb = NULL;
0ab66088 399 int error;
1da177e4 400
078ce640 401 /* binary file operations requires both @sd and its parent */
e72ceb8c 402 if (!sysfs_get_active(attr_sd))
0ab66088 403 return -ENODEV;
1da177e4 404
1da177e4
LT
405 error = -EACCES;
406 if ((file->f_mode & FMODE_WRITE) && !(attr->write || attr->mmap))
7b595756 407 goto err_out;
1da177e4 408 if ((file->f_mode & FMODE_READ) && !(attr->read || attr->mmap))
7b595756 409 goto err_out;
1da177e4
LT
410
411 error = -ENOMEM;
eb361653
TH
412 bb = kzalloc(sizeof(*bb), GFP_KERNEL);
413 if (!bb)
7b595756 414 goto err_out;
1da177e4 415
eb361653
TH
416 bb->buffer = kmalloc(PAGE_SIZE, GFP_KERNEL);
417 if (!bb->buffer)
7b595756 418 goto err_out;
eb361653
TH
419
420 mutex_init(&bb->mutex);
e0edd3c6 421 bb->file = file;
eb361653
TH
422 file->private_data = bb;
423
e0edd3c6
EB
424 mutex_lock(&sysfs_bin_lock);
425 hlist_add_head(&bb->list, &attr_sd->s_bin_attr.buffers);
426 mutex_unlock(&sysfs_bin_lock);
427
078ce640 428 /* open succeeded, put active references */
e72ceb8c 429 sysfs_put_active(attr_sd);
0ab66088 430 return 0;
1da177e4 431
7b595756 432 err_out:
e72ceb8c 433 sysfs_put_active(attr_sd);
0ab66088 434 kfree(bb);
1da177e4
LT
435 return error;
436}
437
438static int release(struct inode * inode, struct file * file)
439{
eb361653 440 struct bin_buffer *bb = file->private_data;
1da177e4 441
e0edd3c6
EB
442 mutex_lock(&sysfs_bin_lock);
443 hlist_del(&bb->list);
444 mutex_unlock(&sysfs_bin_lock);
445
eb361653
TH
446 kfree(bb->buffer);
447 kfree(bb);
1da177e4
LT
448 return 0;
449}
450
4b6f5d20 451const struct file_operations bin_fops = {
1da177e4
LT
452 .read = read,
453 .write = write,
454 .mmap = mmap,
455 .llseek = generic_file_llseek,
456 .open = open,
457 .release = release,
458};
459
e0edd3c6
EB
460
461void unmap_bin_file(struct sysfs_dirent *attr_sd)
462{
463 struct bin_buffer *bb;
e0edd3c6
EB
464
465 if (sysfs_type(attr_sd) != SYSFS_KOBJ_BIN_ATTR)
466 return;
467
468 mutex_lock(&sysfs_bin_lock);
469
b67bfe0d 470 hlist_for_each_entry(bb, &attr_sd->s_bin_attr.buffers, list) {
496ad9aa 471 struct inode *inode = file_inode(bb->file);
e0edd3c6
EB
472
473 unmap_mapping_range(inode->i_mapping, 0, 0, 1);
474 }
475
476 mutex_unlock(&sysfs_bin_lock);
477}
478
1da177e4
LT
479/**
480 * sysfs_create_bin_file - create binary file for object.
481 * @kobj: object.
482 * @attr: attribute descriptor.
1da177e4
LT
483 */
484
66ecb92b
PC
485int sysfs_create_bin_file(struct kobject *kobj,
486 const struct bin_attribute *attr)
1da177e4 487{
608e266a 488 BUG_ON(!kobj || !kobj->sd || !attr);
1da177e4 489
608e266a 490 return sysfs_add_file(kobj->sd, &attr->attr, SYSFS_KOBJ_BIN_ATTR);
1da177e4
LT
491}
492
493
494/**
495 * sysfs_remove_bin_file - remove binary file for object.
496 * @kobj: object.
497 * @attr: attribute descriptor.
1da177e4
LT
498 */
499
66ecb92b
PC
500void sysfs_remove_bin_file(struct kobject *kobj,
501 const struct bin_attribute *attr)
1da177e4 502{
3ff195b0 503 sysfs_hash_and_remove(kobj->sd, NULL, attr->attr.name);
1da177e4
LT
504}
505
506EXPORT_SYMBOL_GPL(sysfs_create_bin_file);
507EXPORT_SYMBOL_GPL(sysfs_remove_bin_file);