Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * file.c - operations for regular (text) files. |
| 3 | */ |
| 4 | |
| 5 | #include <linux/module.h> |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 6 | #include <linux/fsnotify.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 7 | #include <linux/kobject.h> |
Christoph Hellwig | 5f45f1a | 2005-06-23 00:09:12 -0700 | [diff] [blame] | 8 | #include <linux/namei.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include <asm/uaccess.h> |
| 10 | #include <asm/semaphore.h> |
| 11 | |
| 12 | #include "sysfs.h" |
| 13 | |
| 14 | #define to_subsys(k) container_of(k,struct subsystem,kset.kobj) |
| 15 | #define to_sattr(a) container_of(a,struct subsys_attribute,attr) |
| 16 | |
Martin Waitz | 3d41088 | 2005-06-23 22:05:21 -0700 | [diff] [blame] | 17 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 18 | * Subsystem file operations. |
| 19 | * These operations allow subsystems to have files that can be |
| 20 | * read/written. |
| 21 | */ |
| 22 | static ssize_t |
| 23 | subsys_attr_show(struct kobject * kobj, struct attribute * attr, char * page) |
| 24 | { |
| 25 | struct subsystem * s = to_subsys(kobj); |
| 26 | struct subsys_attribute * sattr = to_sattr(attr); |
Dmitry Torokhov | c76d0ab | 2005-04-29 01:22:00 -0500 | [diff] [blame] | 27 | ssize_t ret = -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 28 | |
| 29 | if (sattr->show) |
| 30 | ret = sattr->show(s,page); |
| 31 | return ret; |
| 32 | } |
| 33 | |
| 34 | static ssize_t |
| 35 | subsys_attr_store(struct kobject * kobj, struct attribute * attr, |
| 36 | const char * page, size_t count) |
| 37 | { |
| 38 | struct subsystem * s = to_subsys(kobj); |
| 39 | struct subsys_attribute * sattr = to_sattr(attr); |
Dmitry Torokhov | c76d0ab | 2005-04-29 01:22:00 -0500 | [diff] [blame] | 40 | ssize_t ret = -EIO; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 41 | |
| 42 | if (sattr->store) |
| 43 | ret = sattr->store(s,page,count); |
| 44 | return ret; |
| 45 | } |
| 46 | |
| 47 | static struct sysfs_ops subsys_sysfs_ops = { |
| 48 | .show = subsys_attr_show, |
| 49 | .store = subsys_attr_store, |
| 50 | }; |
| 51 | |
| 52 | |
| 53 | struct sysfs_buffer { |
| 54 | size_t count; |
| 55 | loff_t pos; |
| 56 | char * page; |
| 57 | struct sysfs_ops * ops; |
| 58 | struct semaphore sem; |
| 59 | int needs_read_fill; |
| 60 | }; |
| 61 | |
| 62 | |
| 63 | /** |
| 64 | * fill_read_buffer - allocate and fill buffer from object. |
| 65 | * @dentry: dentry pointer. |
| 66 | * @buffer: data buffer for file. |
| 67 | * |
| 68 | * Allocate @buffer->page, if it hasn't been already, then call the |
| 69 | * kobject's show() method to fill the buffer with this attribute's |
| 70 | * data. |
| 71 | * This is called only once, on the file's first read. |
| 72 | */ |
| 73 | static int fill_read_buffer(struct dentry * dentry, struct sysfs_buffer * buffer) |
| 74 | { |
| 75 | struct attribute * attr = to_attr(dentry); |
| 76 | struct kobject * kobj = to_kobj(dentry->d_parent); |
| 77 | struct sysfs_ops * ops = buffer->ops; |
| 78 | int ret = 0; |
| 79 | ssize_t count; |
| 80 | |
| 81 | if (!buffer->page) |
| 82 | buffer->page = (char *) get_zeroed_page(GFP_KERNEL); |
| 83 | if (!buffer->page) |
| 84 | return -ENOMEM; |
| 85 | |
| 86 | count = ops->show(kobj,attr,buffer->page); |
| 87 | buffer->needs_read_fill = 0; |
| 88 | BUG_ON(count > (ssize_t)PAGE_SIZE); |
| 89 | if (count >= 0) |
| 90 | buffer->count = count; |
| 91 | else |
| 92 | ret = count; |
| 93 | return ret; |
| 94 | } |
| 95 | |
| 96 | |
| 97 | /** |
| 98 | * flush_read_buffer - push buffer to userspace. |
| 99 | * @buffer: data buffer for file. |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 100 | * @buf: user-passed buffer. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 101 | * @count: number of bytes requested. |
| 102 | * @ppos: file position. |
| 103 | * |
| 104 | * Copy the buffer we filled in fill_read_buffer() to userspace. |
| 105 | * This is done at the reader's leisure, copying and advancing |
| 106 | * the amount they specify each time. |
| 107 | * This may be called continuously until the buffer is empty. |
| 108 | */ |
| 109 | static int flush_read_buffer(struct sysfs_buffer * buffer, char __user * buf, |
| 110 | size_t count, loff_t * ppos) |
| 111 | { |
| 112 | int error; |
| 113 | |
| 114 | if (*ppos > buffer->count) |
| 115 | return 0; |
| 116 | |
| 117 | if (count > (buffer->count - *ppos)) |
| 118 | count = buffer->count - *ppos; |
| 119 | |
| 120 | error = copy_to_user(buf,buffer->page + *ppos,count); |
| 121 | if (!error) |
| 122 | *ppos += count; |
| 123 | return error ? -EFAULT : count; |
| 124 | } |
| 125 | |
| 126 | /** |
| 127 | * sysfs_read_file - read an attribute. |
| 128 | * @file: file pointer. |
| 129 | * @buf: buffer to fill. |
| 130 | * @count: number of bytes to read. |
| 131 | * @ppos: starting offset in file. |
| 132 | * |
| 133 | * Userspace wants to read an attribute file. The attribute descriptor |
| 134 | * is in the file's ->d_fsdata. The target object is in the directory's |
| 135 | * ->d_fsdata. |
| 136 | * |
| 137 | * We call fill_read_buffer() to allocate and fill the buffer from the |
| 138 | * object's show() method exactly once (if the read is happening from |
| 139 | * the beginning of the file). That should fill the entire buffer with |
| 140 | * all the data the object has to offer for that attribute. |
| 141 | * We then call flush_read_buffer() to copy the buffer to userspace |
| 142 | * in the increments specified. |
| 143 | */ |
| 144 | |
| 145 | static ssize_t |
| 146 | sysfs_read_file(struct file *file, char __user *buf, size_t count, loff_t *ppos) |
| 147 | { |
| 148 | struct sysfs_buffer * buffer = file->private_data; |
| 149 | ssize_t retval = 0; |
| 150 | |
| 151 | down(&buffer->sem); |
| 152 | if (buffer->needs_read_fill) { |
| 153 | if ((retval = fill_read_buffer(file->f_dentry,buffer))) |
| 154 | goto out; |
| 155 | } |
| 156 | pr_debug("%s: count = %d, ppos = %lld, buf = %s\n", |
| 157 | __FUNCTION__,count,*ppos,buffer->page); |
| 158 | retval = flush_read_buffer(buffer,buf,count,ppos); |
| 159 | out: |
| 160 | up(&buffer->sem); |
| 161 | return retval; |
| 162 | } |
| 163 | |
| 164 | |
| 165 | /** |
| 166 | * fill_write_buffer - copy buffer from userspace. |
| 167 | * @buffer: data buffer for file. |
Martin Waitz | 67be2dd | 2005-05-01 08:59:26 -0700 | [diff] [blame] | 168 | * @buf: data from user. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 169 | * @count: number of bytes in @userbuf. |
| 170 | * |
| 171 | * Allocate @buffer->page if it hasn't been already, then |
| 172 | * copy the user-supplied buffer into it. |
| 173 | */ |
| 174 | |
| 175 | static int |
| 176 | fill_write_buffer(struct sysfs_buffer * buffer, const char __user * buf, size_t count) |
| 177 | { |
| 178 | int error; |
| 179 | |
| 180 | if (!buffer->page) |
| 181 | buffer->page = (char *)get_zeroed_page(GFP_KERNEL); |
| 182 | if (!buffer->page) |
| 183 | return -ENOMEM; |
| 184 | |
| 185 | if (count >= PAGE_SIZE) |
Jon Smirl | 9d9d27f | 2005-06-14 09:54:54 -0400 | [diff] [blame] | 186 | count = PAGE_SIZE; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | error = copy_from_user(buffer->page,buf,count); |
| 188 | buffer->needs_read_fill = 1; |
| 189 | return error ? -EFAULT : count; |
| 190 | } |
| 191 | |
| 192 | |
| 193 | /** |
| 194 | * flush_write_buffer - push buffer to kobject. |
Martin Waitz | 3d41088 | 2005-06-23 22:05:21 -0700 | [diff] [blame] | 195 | * @dentry: dentry to the attribute |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 196 | * @buffer: data buffer for file. |
Martin Waitz | 3d41088 | 2005-06-23 22:05:21 -0700 | [diff] [blame] | 197 | * @count: number of bytes |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 198 | * |
| 199 | * Get the correct pointers for the kobject and the attribute we're |
| 200 | * dealing with, then call the store() method for the attribute, |
| 201 | * passing the buffer that we acquired in fill_write_buffer(). |
| 202 | */ |
| 203 | |
| 204 | static int |
| 205 | flush_write_buffer(struct dentry * dentry, struct sysfs_buffer * buffer, size_t count) |
| 206 | { |
| 207 | struct attribute * attr = to_attr(dentry); |
| 208 | struct kobject * kobj = to_kobj(dentry->d_parent); |
| 209 | struct sysfs_ops * ops = buffer->ops; |
| 210 | |
| 211 | return ops->store(kobj,attr,buffer->page,count); |
| 212 | } |
| 213 | |
| 214 | |
| 215 | /** |
| 216 | * sysfs_write_file - write an attribute. |
| 217 | * @file: file pointer |
| 218 | * @buf: data to write |
| 219 | * @count: number of bytes |
| 220 | * @ppos: starting offset |
| 221 | * |
| 222 | * Similar to sysfs_read_file(), though working in the opposite direction. |
| 223 | * We allocate and fill the data from the user in fill_write_buffer(), |
| 224 | * then push it to the kobject in flush_write_buffer(). |
| 225 | * There is no easy way for us to know if userspace is only doing a partial |
| 226 | * write, so we don't support them. We expect the entire buffer to come |
| 227 | * on the first write. |
| 228 | * Hint: if you're writing a value, first read the file, modify only the |
| 229 | * the value you're changing, then write entire buffer back. |
| 230 | */ |
| 231 | |
| 232 | static ssize_t |
| 233 | sysfs_write_file(struct file *file, const char __user *buf, size_t count, loff_t *ppos) |
| 234 | { |
| 235 | struct sysfs_buffer * buffer = file->private_data; |
| 236 | ssize_t len; |
| 237 | |
| 238 | down(&buffer->sem); |
| 239 | len = fill_write_buffer(buffer, buf, count); |
| 240 | if (len > 0) |
| 241 | len = flush_write_buffer(file->f_dentry, buffer, len); |
| 242 | if (len > 0) |
| 243 | *ppos += len; |
| 244 | up(&buffer->sem); |
| 245 | return len; |
| 246 | } |
| 247 | |
| 248 | static int check_perm(struct inode * inode, struct file * file) |
| 249 | { |
| 250 | struct kobject *kobj = sysfs_get_kobject(file->f_dentry->d_parent); |
| 251 | struct attribute * attr = to_attr(file->f_dentry); |
| 252 | struct sysfs_buffer * buffer; |
| 253 | struct sysfs_ops * ops = NULL; |
| 254 | int error = 0; |
| 255 | |
| 256 | if (!kobj || !attr) |
| 257 | goto Einval; |
| 258 | |
| 259 | /* Grab the module reference for this attribute if we have one */ |
| 260 | if (!try_module_get(attr->owner)) { |
| 261 | error = -ENODEV; |
| 262 | goto Done; |
| 263 | } |
| 264 | |
| 265 | /* if the kobject has no ktype, then we assume that it is a subsystem |
| 266 | * itself, and use ops for it. |
| 267 | */ |
| 268 | if (kobj->kset && kobj->kset->ktype) |
| 269 | ops = kobj->kset->ktype->sysfs_ops; |
| 270 | else if (kobj->ktype) |
| 271 | ops = kobj->ktype->sysfs_ops; |
| 272 | else |
| 273 | ops = &subsys_sysfs_ops; |
| 274 | |
| 275 | /* No sysfs operations, either from having no subsystem, |
| 276 | * or the subsystem have no operations. |
| 277 | */ |
| 278 | if (!ops) |
| 279 | goto Eaccess; |
| 280 | |
| 281 | /* File needs write support. |
| 282 | * The inode's perms must say it's ok, |
| 283 | * and we must have a store method. |
| 284 | */ |
| 285 | if (file->f_mode & FMODE_WRITE) { |
| 286 | |
| 287 | if (!(inode->i_mode & S_IWUGO) || !ops->store) |
| 288 | goto Eaccess; |
| 289 | |
| 290 | } |
| 291 | |
| 292 | /* File needs read support. |
| 293 | * The inode's perms must say it's ok, and we there |
| 294 | * must be a show method for it. |
| 295 | */ |
| 296 | if (file->f_mode & FMODE_READ) { |
| 297 | if (!(inode->i_mode & S_IRUGO) || !ops->show) |
| 298 | goto Eaccess; |
| 299 | } |
| 300 | |
| 301 | /* No error? Great, allocate a buffer for the file, and store it |
| 302 | * it in file->private_data for easy access. |
| 303 | */ |
Eric Sesterhenn | 58d4928 | 2006-02-22 11:18:15 +0100 | [diff] [blame] | 304 | buffer = kzalloc(sizeof(struct sysfs_buffer), GFP_KERNEL); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 305 | if (buffer) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 306 | init_MUTEX(&buffer->sem); |
| 307 | buffer->needs_read_fill = 1; |
| 308 | buffer->ops = ops; |
| 309 | file->private_data = buffer; |
| 310 | } else |
| 311 | error = -ENOMEM; |
| 312 | goto Done; |
| 313 | |
| 314 | Einval: |
| 315 | error = -EINVAL; |
| 316 | goto Done; |
| 317 | Eaccess: |
| 318 | error = -EACCES; |
| 319 | module_put(attr->owner); |
| 320 | Done: |
| 321 | if (error && kobj) |
| 322 | kobject_put(kobj); |
| 323 | return error; |
| 324 | } |
| 325 | |
| 326 | static int sysfs_open_file(struct inode * inode, struct file * filp) |
| 327 | { |
| 328 | return check_perm(inode,filp); |
| 329 | } |
| 330 | |
| 331 | static int sysfs_release(struct inode * inode, struct file * filp) |
| 332 | { |
| 333 | struct kobject * kobj = to_kobj(filp->f_dentry->d_parent); |
| 334 | struct attribute * attr = to_attr(filp->f_dentry); |
| 335 | struct module * owner = attr->owner; |
| 336 | struct sysfs_buffer * buffer = filp->private_data; |
| 337 | |
| 338 | if (kobj) |
| 339 | kobject_put(kobj); |
| 340 | /* After this point, attr should not be accessed. */ |
| 341 | module_put(owner); |
| 342 | |
| 343 | if (buffer) { |
| 344 | if (buffer->page) |
| 345 | free_page((unsigned long)buffer->page); |
| 346 | kfree(buffer); |
| 347 | } |
| 348 | return 0; |
| 349 | } |
| 350 | |
| 351 | struct file_operations sysfs_file_operations = { |
| 352 | .read = sysfs_read_file, |
| 353 | .write = sysfs_write_file, |
| 354 | .llseek = generic_file_llseek, |
| 355 | .open = sysfs_open_file, |
| 356 | .release = sysfs_release, |
| 357 | }; |
| 358 | |
| 359 | |
| 360 | int sysfs_add_file(struct dentry * dir, const struct attribute * attr, int type) |
| 361 | { |
| 362 | struct sysfs_dirent * parent_sd = dir->d_fsdata; |
| 363 | umode_t mode = (attr->mode & S_IALLUGO) | S_IFREG; |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 364 | int error = -EEXIST; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 365 | |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 366 | mutex_lock(&dir->d_inode->i_mutex); |
Maneesh Soni | c516865 | 2006-03-09 19:40:14 +0530 | [diff] [blame] | 367 | if (!sysfs_dirent_exist(parent_sd, attr->name)) |
| 368 | error = sysfs_make_dirent(parent_sd, NULL, (void *)attr, |
| 369 | mode, type); |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 370 | mutex_unlock(&dir->d_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 371 | |
| 372 | return error; |
| 373 | } |
| 374 | |
| 375 | |
| 376 | /** |
| 377 | * sysfs_create_file - create an attribute file for an object. |
| 378 | * @kobj: object we're creating for. |
| 379 | * @attr: atrribute descriptor. |
| 380 | */ |
| 381 | |
| 382 | int sysfs_create_file(struct kobject * kobj, const struct attribute * attr) |
| 383 | { |
| 384 | BUG_ON(!kobj || !kobj->dentry || !attr); |
| 385 | |
| 386 | return sysfs_add_file(kobj->dentry, attr, SYSFS_KOBJ_ATTR); |
| 387 | |
| 388 | } |
| 389 | |
| 390 | |
| 391 | /** |
| 392 | * sysfs_update_file - update the modified timestamp on an object attribute. |
| 393 | * @kobj: object we're acting for. |
| 394 | * @attr: attribute descriptor. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | */ |
| 396 | int sysfs_update_file(struct kobject * kobj, const struct attribute * attr) |
| 397 | { |
| 398 | struct dentry * dir = kobj->dentry; |
| 399 | struct dentry * victim; |
| 400 | int res = -ENOENT; |
| 401 | |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 402 | mutex_lock(&dir->d_inode->i_mutex); |
Christoph Hellwig | 5f45f1a | 2005-06-23 00:09:12 -0700 | [diff] [blame] | 403 | victim = lookup_one_len(attr->name, dir, strlen(attr->name)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | if (!IS_ERR(victim)) { |
| 405 | /* make sure dentry is really there */ |
| 406 | if (victim->d_inode && |
| 407 | (victim->d_parent->d_inode == dir->d_inode)) { |
| 408 | victim->d_inode->i_mtime = CURRENT_TIME; |
Robert Love | 0eeca28 | 2005-07-12 17:06:03 -0400 | [diff] [blame] | 409 | fsnotify_modify(victim); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 410 | |
| 411 | /** |
| 412 | * Drop reference from initial sysfs_get_dentry(). |
| 413 | */ |
| 414 | dput(victim); |
| 415 | res = 0; |
| 416 | } else |
| 417 | d_drop(victim); |
| 418 | |
| 419 | /** |
| 420 | * Drop the reference acquired from sysfs_get_dentry() above. |
| 421 | */ |
| 422 | dput(victim); |
| 423 | } |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 424 | mutex_unlock(&dir->d_inode->i_mutex); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 425 | |
| 426 | return res; |
| 427 | } |
| 428 | |
| 429 | |
| 430 | /** |
Kay Sievers | 31e5abe | 2005-04-18 21:57:32 -0700 | [diff] [blame] | 431 | * sysfs_chmod_file - update the modified mode value on an object attribute. |
| 432 | * @kobj: object we're acting for. |
| 433 | * @attr: attribute descriptor. |
| 434 | * @mode: file permissions. |
| 435 | * |
| 436 | */ |
| 437 | int sysfs_chmod_file(struct kobject *kobj, struct attribute *attr, mode_t mode) |
| 438 | { |
| 439 | struct dentry *dir = kobj->dentry; |
| 440 | struct dentry *victim; |
Maneesh Soni | bc062b1 | 2005-07-29 12:13:35 -0700 | [diff] [blame] | 441 | struct inode * inode; |
| 442 | struct iattr newattrs; |
Kay Sievers | 31e5abe | 2005-04-18 21:57:32 -0700 | [diff] [blame] | 443 | int res = -ENOENT; |
| 444 | |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 445 | mutex_lock(&dir->d_inode->i_mutex); |
Christoph Hellwig | 5f45f1a | 2005-06-23 00:09:12 -0700 | [diff] [blame] | 446 | victim = lookup_one_len(attr->name, dir, strlen(attr->name)); |
Kay Sievers | 31e5abe | 2005-04-18 21:57:32 -0700 | [diff] [blame] | 447 | if (!IS_ERR(victim)) { |
| 448 | if (victim->d_inode && |
| 449 | (victim->d_parent->d_inode == dir->d_inode)) { |
Maneesh Soni | bc062b1 | 2005-07-29 12:13:35 -0700 | [diff] [blame] | 450 | inode = victim->d_inode; |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 451 | mutex_lock(&inode->i_mutex); |
Maneesh Soni | bc062b1 | 2005-07-29 12:13:35 -0700 | [diff] [blame] | 452 | newattrs.ia_mode = (mode & S_IALLUGO) | |
| 453 | (inode->i_mode & ~S_IALLUGO); |
| 454 | newattrs.ia_valid = ATTR_MODE | ATTR_CTIME; |
| 455 | res = notify_change(victim, &newattrs); |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 456 | mutex_unlock(&inode->i_mutex); |
Kay Sievers | 31e5abe | 2005-04-18 21:57:32 -0700 | [diff] [blame] | 457 | } |
Maneesh Soni | bc062b1 | 2005-07-29 12:13:35 -0700 | [diff] [blame] | 458 | dput(victim); |
Kay Sievers | 31e5abe | 2005-04-18 21:57:32 -0700 | [diff] [blame] | 459 | } |
Jes Sorensen | 1b1dcc1 | 2006-01-09 15:59:24 -0800 | [diff] [blame] | 460 | mutex_unlock(&dir->d_inode->i_mutex); |
Kay Sievers | 31e5abe | 2005-04-18 21:57:32 -0700 | [diff] [blame] | 461 | |
| 462 | return res; |
| 463 | } |
| 464 | EXPORT_SYMBOL_GPL(sysfs_chmod_file); |
| 465 | |
| 466 | |
| 467 | /** |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 468 | * sysfs_remove_file - remove an object attribute. |
| 469 | * @kobj: object we're acting for. |
| 470 | * @attr: attribute descriptor. |
| 471 | * |
| 472 | * Hash the attribute name and kill the victim. |
| 473 | */ |
| 474 | |
| 475 | void sysfs_remove_file(struct kobject * kobj, const struct attribute * attr) |
| 476 | { |
| 477 | sysfs_hash_and_remove(kobj->dentry,attr->name); |
| 478 | } |
| 479 | |
| 480 | |
| 481 | EXPORT_SYMBOL_GPL(sysfs_create_file); |
| 482 | EXPORT_SYMBOL_GPL(sysfs_remove_file); |
| 483 | EXPORT_SYMBOL_GPL(sysfs_update_file); |