diff options
Diffstat (limited to 'fs/libfs.c')
-rw-r--r-- | fs/libfs.c | 70 |
1 files changed, 14 insertions, 56 deletions
diff --git a/fs/libfs.c b/fs/libfs.c index dcaf972cbf1b..0a9da95317f7 100644 --- a/fs/libfs.c +++ b/fs/libfs.c | |||
@@ -327,77 +327,35 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry, | |||
327 | } | 327 | } |
328 | 328 | ||
329 | /** | 329 | /** |
330 | * simple_setsize - handle core mm and vfs requirements for file size change | 330 | * simple_setattr - setattr for simple filesystem |
331 | * @inode: inode | ||
332 | * @newsize: new file size | ||
333 | * | ||
334 | * Returns 0 on success, -error on failure. | ||
335 | * | ||
336 | * simple_setsize must be called with inode_mutex held. | ||
337 | * | ||
338 | * simple_setsize will check that the requested new size is OK (see | ||
339 | * inode_newsize_ok), and then will perform the necessary i_size update | ||
340 | * and pagecache truncation (if necessary). It will be typically be called | ||
341 | * from the filesystem's setattr function when ATTR_SIZE is passed in. | ||
342 | * | ||
343 | * The inode itself must have correct permissions and attributes to allow | ||
344 | * i_size to be changed, this function then just checks that the new size | ||
345 | * requested is valid. | ||
346 | * | ||
347 | * In the case of simple in-memory filesystems with inodes stored solely | ||
348 | * in the inode cache, and file data in the pagecache, nothing more needs | ||
349 | * to be done to satisfy a truncate request. Filesystems with on-disk | ||
350 | * blocks for example will need to free them in the case of truncate, in | ||
351 | * that case it may be easier not to use simple_setsize (but each of its | ||
352 | * components will likely be required at some point to update pagecache | ||
353 | * and inode etc). | ||
354 | */ | ||
355 | int simple_setsize(struct inode *inode, loff_t newsize) | ||
356 | { | ||
357 | loff_t oldsize; | ||
358 | int error; | ||
359 | |||
360 | error = inode_newsize_ok(inode, newsize); | ||
361 | if (error) | ||
362 | return error; | ||
363 | |||
364 | oldsize = inode->i_size; | ||
365 | i_size_write(inode, newsize); | ||
366 | truncate_pagecache(inode, oldsize, newsize); | ||
367 | |||
368 | return error; | ||
369 | } | ||
370 | EXPORT_SYMBOL(simple_setsize); | ||
371 | |||
372 | /** | ||
373 | * simple_setattr - setattr for simple in-memory filesystem | ||
374 | * @dentry: dentry | 331 | * @dentry: dentry |
375 | * @iattr: iattr structure | 332 | * @iattr: iattr structure |
376 | * | 333 | * |
377 | * Returns 0 on success, -error on failure. | 334 | * Returns 0 on success, -error on failure. |
378 | * | 335 | * |
379 | * simple_setattr implements setattr for an in-memory filesystem which | 336 | * simple_setattr is a simple ->setattr implementation without a proper |
380 | * does not store its own file data or metadata (eg. uses the page cache | 337 | * implementation of size changes. |
381 | * and inode cache as its data store). | 338 | * |
339 | * It can either be used for in-memory filesystems or special files | ||
340 | * on simple regular filesystems. Anything that needs to change on-disk | ||
341 | * or wire state on size changes needs its own setattr method. | ||
382 | */ | 342 | */ |
383 | int simple_setattr(struct dentry *dentry, struct iattr *iattr) | 343 | int simple_setattr(struct dentry *dentry, struct iattr *iattr) |
384 | { | 344 | { |
385 | struct inode *inode = dentry->d_inode; | 345 | struct inode *inode = dentry->d_inode; |
386 | int error; | 346 | int error; |
387 | 347 | ||
348 | WARN_ON_ONCE(inode->i_op->truncate); | ||
349 | |||
388 | error = inode_change_ok(inode, iattr); | 350 | error = inode_change_ok(inode, iattr); |
389 | if (error) | 351 | if (error) |
390 | return error; | 352 | return error; |
391 | 353 | ||
392 | if (iattr->ia_valid & ATTR_SIZE) { | 354 | if (iattr->ia_valid & ATTR_SIZE) |
393 | error = simple_setsize(inode, iattr->ia_size); | 355 | truncate_setsize(inode, iattr->ia_size); |
394 | if (error) | 356 | setattr_copy(inode, iattr); |
395 | return error; | 357 | mark_inode_dirty(inode); |
396 | } | 358 | return 0; |
397 | |||
398 | generic_setattr(inode, iattr); | ||
399 | |||
400 | return error; | ||
401 | } | 359 | } |
402 | EXPORT_SYMBOL(simple_setattr); | 360 | EXPORT_SYMBOL(simple_setattr); |
403 | 361 | ||