mfd: Support 88pm8606 in 860x driver
[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / fs / libfs.c
blob9e50bcf55857eaebd8fc4106f21bae8ad69afbf1
1 /*
2 * fs/libfs.c
3 * Library for filesystems writers.
4 */
6 #include <linux/module.h>
7 #include <linux/pagemap.h>
8 #include <linux/mount.h>
9 #include <linux/vfs.h>
10 #include <linux/mutex.h>
11 #include <linux/exportfs.h>
12 #include <linux/writeback.h>
13 #include <linux/buffer_head.h>
15 #include <asm/uaccess.h>
17 int simple_getattr(struct vfsmount *mnt, struct dentry *dentry,
18 struct kstat *stat)
20 struct inode *inode = dentry->d_inode;
21 generic_fillattr(inode, stat);
22 stat->blocks = inode->i_mapping->nrpages << (PAGE_CACHE_SHIFT - 9);
23 return 0;
26 int simple_statfs(struct dentry *dentry, struct kstatfs *buf)
28 buf->f_type = dentry->d_sb->s_magic;
29 buf->f_bsize = PAGE_CACHE_SIZE;
30 buf->f_namelen = NAME_MAX;
31 return 0;
35 * Retaining negative dentries for an in-memory filesystem just wastes
36 * memory and lookup time: arrange for them to be deleted immediately.
38 static int simple_delete_dentry(struct dentry *dentry)
40 return 1;
44 * Lookup the data. This is trivial - if the dentry didn't already
45 * exist, we know it is negative. Set d_op to delete negative dentries.
47 struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
49 static const struct dentry_operations simple_dentry_operations = {
50 .d_delete = simple_delete_dentry,
53 if (dentry->d_name.len > NAME_MAX)
54 return ERR_PTR(-ENAMETOOLONG);
55 dentry->d_op = &simple_dentry_operations;
56 d_add(dentry, NULL);
57 return NULL;
60 int simple_sync_file(struct file * file, struct dentry *dentry, int datasync)
62 return 0;
65 int dcache_dir_open(struct inode *inode, struct file *file)
67 static struct qstr cursor_name = {.len = 1, .name = "."};
69 file->private_data = d_alloc(file->f_path.dentry, &cursor_name);
71 return file->private_data ? 0 : -ENOMEM;
74 int dcache_dir_close(struct inode *inode, struct file *file)
76 dput(file->private_data);
77 return 0;
80 loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin)
82 mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
83 switch (origin) {
84 case 1:
85 offset += file->f_pos;
86 case 0:
87 if (offset >= 0)
88 break;
89 default:
90 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
91 return -EINVAL;
93 if (offset != file->f_pos) {
94 file->f_pos = offset;
95 if (file->f_pos >= 2) {
96 struct list_head *p;
97 struct dentry *cursor = file->private_data;
98 loff_t n = file->f_pos - 2;
100 spin_lock(&dcache_lock);
101 list_del(&cursor->d_u.d_child);
102 p = file->f_path.dentry->d_subdirs.next;
103 while (n && p != &file->f_path.dentry->d_subdirs) {
104 struct dentry *next;
105 next = list_entry(p, struct dentry, d_u.d_child);
106 if (!d_unhashed(next) && next->d_inode)
107 n--;
108 p = p->next;
110 list_add_tail(&cursor->d_u.d_child, p);
111 spin_unlock(&dcache_lock);
114 mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
115 return offset;
118 /* Relationship between i_mode and the DT_xxx types */
119 static inline unsigned char dt_type(struct inode *inode)
121 return (inode->i_mode >> 12) & 15;
125 * Directory is locked and all positive dentries in it are safe, since
126 * for ramfs-type trees they can't go away without unlink() or rmdir(),
127 * both impossible due to the lock on directory.
130 int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
132 struct dentry *dentry = filp->f_path.dentry;
133 struct dentry *cursor = filp->private_data;
134 struct list_head *p, *q = &cursor->d_u.d_child;
135 ino_t ino;
136 int i = filp->f_pos;
138 switch (i) {
139 case 0:
140 ino = dentry->d_inode->i_ino;
141 if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0)
142 break;
143 filp->f_pos++;
144 i++;
145 /* fallthrough */
146 case 1:
147 ino = parent_ino(dentry);
148 if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0)
149 break;
150 filp->f_pos++;
151 i++;
152 /* fallthrough */
153 default:
154 spin_lock(&dcache_lock);
155 if (filp->f_pos == 2)
156 list_move(q, &dentry->d_subdirs);
158 for (p=q->next; p != &dentry->d_subdirs; p=p->next) {
159 struct dentry *next;
160 next = list_entry(p, struct dentry, d_u.d_child);
161 if (d_unhashed(next) || !next->d_inode)
162 continue;
164 spin_unlock(&dcache_lock);
165 if (filldir(dirent, next->d_name.name,
166 next->d_name.len, filp->f_pos,
167 next->d_inode->i_ino,
168 dt_type(next->d_inode)) < 0)
169 return 0;
170 spin_lock(&dcache_lock);
171 /* next is still alive */
172 list_move(q, p);
173 p = q;
174 filp->f_pos++;
176 spin_unlock(&dcache_lock);
178 return 0;
181 ssize_t generic_read_dir(struct file *filp, char __user *buf, size_t siz, loff_t *ppos)
183 return -EISDIR;
186 const struct file_operations simple_dir_operations = {
187 .open = dcache_dir_open,
188 .release = dcache_dir_close,
189 .llseek = dcache_dir_lseek,
190 .read = generic_read_dir,
191 .readdir = dcache_readdir,
192 .fsync = simple_sync_file,
195 const struct inode_operations simple_dir_inode_operations = {
196 .lookup = simple_lookup,
199 static const struct super_operations simple_super_operations = {
200 .statfs = simple_statfs,
204 * Common helper for pseudo-filesystems (sockfs, pipefs, bdev - stuff that
205 * will never be mountable)
207 int get_sb_pseudo(struct file_system_type *fs_type, char *name,
208 const struct super_operations *ops, unsigned long magic,
209 struct vfsmount *mnt)
211 struct super_block *s = sget(fs_type, NULL, set_anon_super, NULL);
212 struct dentry *dentry;
213 struct inode *root;
214 struct qstr d_name = {.name = name, .len = strlen(name)};
216 if (IS_ERR(s))
217 return PTR_ERR(s);
219 s->s_flags = MS_NOUSER;
220 s->s_maxbytes = MAX_LFS_FILESIZE;
221 s->s_blocksize = PAGE_SIZE;
222 s->s_blocksize_bits = PAGE_SHIFT;
223 s->s_magic = magic;
224 s->s_op = ops ? ops : &simple_super_operations;
225 s->s_time_gran = 1;
226 root = new_inode(s);
227 if (!root)
228 goto Enomem;
230 * since this is the first inode, make it number 1. New inodes created
231 * after this must take care not to collide with it (by passing
232 * max_reserved of 1 to iunique).
234 root->i_ino = 1;
235 root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
236 root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
237 dentry = d_alloc(NULL, &d_name);
238 if (!dentry) {
239 iput(root);
240 goto Enomem;
242 dentry->d_sb = s;
243 dentry->d_parent = dentry;
244 d_instantiate(dentry, root);
245 s->s_root = dentry;
246 s->s_flags |= MS_ACTIVE;
247 simple_set_mnt(mnt, s);
248 return 0;
250 Enomem:
251 deactivate_locked_super(s);
252 return -ENOMEM;
255 int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
257 struct inode *inode = old_dentry->d_inode;
259 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
260 inc_nlink(inode);
261 atomic_inc(&inode->i_count);
262 dget(dentry);
263 d_instantiate(dentry, inode);
264 return 0;
267 static inline int simple_positive(struct dentry *dentry)
269 return dentry->d_inode && !d_unhashed(dentry);
272 int simple_empty(struct dentry *dentry)
274 struct dentry *child;
275 int ret = 0;
277 spin_lock(&dcache_lock);
278 list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
279 if (simple_positive(child))
280 goto out;
281 ret = 1;
282 out:
283 spin_unlock(&dcache_lock);
284 return ret;
287 int simple_unlink(struct inode *dir, struct dentry *dentry)
289 struct inode *inode = dentry->d_inode;
291 inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
292 drop_nlink(inode);
293 dput(dentry);
294 return 0;
297 int simple_rmdir(struct inode *dir, struct dentry *dentry)
299 if (!simple_empty(dentry))
300 return -ENOTEMPTY;
302 drop_nlink(dentry->d_inode);
303 simple_unlink(dir, dentry);
304 drop_nlink(dir);
305 return 0;
308 int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
309 struct inode *new_dir, struct dentry *new_dentry)
311 struct inode *inode = old_dentry->d_inode;
312 int they_are_dirs = S_ISDIR(old_dentry->d_inode->i_mode);
314 if (!simple_empty(new_dentry))
315 return -ENOTEMPTY;
317 if (new_dentry->d_inode) {
318 simple_unlink(new_dir, new_dentry);
319 if (they_are_dirs)
320 drop_nlink(old_dir);
321 } else if (they_are_dirs) {
322 drop_nlink(old_dir);
323 inc_nlink(new_dir);
326 old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime =
327 new_dir->i_mtime = inode->i_ctime = CURRENT_TIME;
329 return 0;
332 int simple_readpage(struct file *file, struct page *page)
334 clear_highpage(page);
335 flush_dcache_page(page);
336 SetPageUptodate(page);
337 unlock_page(page);
338 return 0;
341 int simple_write_begin(struct file *file, struct address_space *mapping,
342 loff_t pos, unsigned len, unsigned flags,
343 struct page **pagep, void **fsdata)
345 struct page *page;
346 pgoff_t index;
348 index = pos >> PAGE_CACHE_SHIFT;
350 page = grab_cache_page_write_begin(mapping, index, flags);
351 if (!page)
352 return -ENOMEM;
354 *pagep = page;
356 if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
357 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
359 zero_user_segments(page, 0, from, from + len, PAGE_CACHE_SIZE);
361 return 0;
365 * simple_write_end - .write_end helper for non-block-device FSes
366 * @available: See .write_end of address_space_operations
367 * @file: "
368 * @mapping: "
369 * @pos: "
370 * @len: "
371 * @copied: "
372 * @page: "
373 * @fsdata: "
375 * simple_write_end does the minimum needed for updating a page after writing is
376 * done. It has the same API signature as the .write_end of
377 * address_space_operations vector. So it can just be set onto .write_end for
378 * FSes that don't need any other processing. i_mutex is assumed to be held.
379 * Block based filesystems should use generic_write_end().
380 * NOTE: Even though i_size might get updated by this function, mark_inode_dirty
381 * is not called, so a filesystem that actually does store data in .write_inode
382 * should extend on what's done here with a call to mark_inode_dirty() in the
383 * case that i_size has changed.
385 int simple_write_end(struct file *file, struct address_space *mapping,
386 loff_t pos, unsigned len, unsigned copied,
387 struct page *page, void *fsdata)
389 struct inode *inode = page->mapping->host;
390 loff_t last_pos = pos + copied;
392 /* zero the stale part of the page if we did a short copy */
393 if (copied < len) {
394 unsigned from = pos & (PAGE_CACHE_SIZE - 1);
396 zero_user(page, from + copied, len - copied);
399 if (!PageUptodate(page))
400 SetPageUptodate(page);
402 * No need to use i_size_read() here, the i_size
403 * cannot change under us because we hold the i_mutex.
405 if (last_pos > inode->i_size)
406 i_size_write(inode, last_pos);
408 set_page_dirty(page);
409 unlock_page(page);
410 page_cache_release(page);
412 return copied;
416 * the inodes created here are not hashed. If you use iunique to generate
417 * unique inode values later for this filesystem, then you must take care
418 * to pass it an appropriate max_reserved value to avoid collisions.
420 int simple_fill_super(struct super_block *s, int magic, struct tree_descr *files)
422 struct inode *inode;
423 struct dentry *root;
424 struct dentry *dentry;
425 int i;
427 s->s_blocksize = PAGE_CACHE_SIZE;
428 s->s_blocksize_bits = PAGE_CACHE_SHIFT;
429 s->s_magic = magic;
430 s->s_op = &simple_super_operations;
431 s->s_time_gran = 1;
433 inode = new_inode(s);
434 if (!inode)
435 return -ENOMEM;
437 * because the root inode is 1, the files array must not contain an
438 * entry at index 1
440 inode->i_ino = 1;
441 inode->i_mode = S_IFDIR | 0755;
442 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
443 inode->i_op = &simple_dir_inode_operations;
444 inode->i_fop = &simple_dir_operations;
445 inode->i_nlink = 2;
446 root = d_alloc_root(inode);
447 if (!root) {
448 iput(inode);
449 return -ENOMEM;
451 for (i = 0; !files->name || files->name[0]; i++, files++) {
452 if (!files->name)
453 continue;
455 /* warn if it tries to conflict with the root inode */
456 if (unlikely(i == 1))
457 printk(KERN_WARNING "%s: %s passed in a files array"
458 "with an index of 1!\n", __func__,
459 s->s_type->name);
461 dentry = d_alloc_name(root, files->name);
462 if (!dentry)
463 goto out;
464 inode = new_inode(s);
465 if (!inode)
466 goto out;
467 inode->i_mode = S_IFREG | files->mode;
468 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
469 inode->i_fop = files->ops;
470 inode->i_ino = i;
471 d_add(dentry, inode);
473 s->s_root = root;
474 return 0;
475 out:
476 d_genocide(root);
477 dput(root);
478 return -ENOMEM;
481 static DEFINE_SPINLOCK(pin_fs_lock);
483 int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *count)
485 struct vfsmount *mnt = NULL;
486 spin_lock(&pin_fs_lock);
487 if (unlikely(!*mount)) {
488 spin_unlock(&pin_fs_lock);
489 mnt = vfs_kern_mount(type, 0, type->name, NULL);
490 if (IS_ERR(mnt))
491 return PTR_ERR(mnt);
492 spin_lock(&pin_fs_lock);
493 if (!*mount)
494 *mount = mnt;
496 mntget(*mount);
497 ++*count;
498 spin_unlock(&pin_fs_lock);
499 mntput(mnt);
500 return 0;
503 void simple_release_fs(struct vfsmount **mount, int *count)
505 struct vfsmount *mnt;
506 spin_lock(&pin_fs_lock);
507 mnt = *mount;
508 if (!--*count)
509 *mount = NULL;
510 spin_unlock(&pin_fs_lock);
511 mntput(mnt);
515 * simple_read_from_buffer - copy data from the buffer to user space
516 * @to: the user space buffer to read to
517 * @count: the maximum number of bytes to read
518 * @ppos: the current position in the buffer
519 * @from: the buffer to read from
520 * @available: the size of the buffer
522 * The simple_read_from_buffer() function reads up to @count bytes from the
523 * buffer @from at offset @ppos into the user space address starting at @to.
525 * On success, the number of bytes read is returned and the offset @ppos is
526 * advanced by this number, or negative value is returned on error.
528 ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
529 const void *from, size_t available)
531 loff_t pos = *ppos;
532 size_t ret;
534 if (pos < 0)
535 return -EINVAL;
536 if (pos >= available || !count)
537 return 0;
538 if (count > available - pos)
539 count = available - pos;
540 ret = copy_to_user(to, from + pos, count);
541 if (ret == count)
542 return -EFAULT;
543 count -= ret;
544 *ppos = pos + count;
545 return count;
549 * memory_read_from_buffer - copy data from the buffer
550 * @to: the kernel space buffer to read to
551 * @count: the maximum number of bytes to read
552 * @ppos: the current position in the buffer
553 * @from: the buffer to read from
554 * @available: the size of the buffer
556 * The memory_read_from_buffer() function reads up to @count bytes from the
557 * buffer @from at offset @ppos into the kernel space address starting at @to.
559 * On success, the number of bytes read is returned and the offset @ppos is
560 * advanced by this number, or negative value is returned on error.
562 ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
563 const void *from, size_t available)
565 loff_t pos = *ppos;
567 if (pos < 0)
568 return -EINVAL;
569 if (pos >= available)
570 return 0;
571 if (count > available - pos)
572 count = available - pos;
573 memcpy(to, from + pos, count);
574 *ppos = pos + count;
576 return count;
580 * Transaction based IO.
581 * The file expects a single write which triggers the transaction, and then
582 * possibly a read which collects the result - which is stored in a
583 * file-local buffer.
586 void simple_transaction_set(struct file *file, size_t n)
588 struct simple_transaction_argresp *ar = file->private_data;
590 BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
593 * The barrier ensures that ar->size will really remain zero until
594 * ar->data is ready for reading.
596 smp_mb();
597 ar->size = n;
600 char *simple_transaction_get(struct file *file, const char __user *buf, size_t size)
602 struct simple_transaction_argresp *ar;
603 static DEFINE_SPINLOCK(simple_transaction_lock);
605 if (size > SIMPLE_TRANSACTION_LIMIT - 1)
606 return ERR_PTR(-EFBIG);
608 ar = (struct simple_transaction_argresp *)get_zeroed_page(GFP_KERNEL);
609 if (!ar)
610 return ERR_PTR(-ENOMEM);
612 spin_lock(&simple_transaction_lock);
614 /* only one write allowed per open */
615 if (file->private_data) {
616 spin_unlock(&simple_transaction_lock);
617 free_page((unsigned long)ar);
618 return ERR_PTR(-EBUSY);
621 file->private_data = ar;
623 spin_unlock(&simple_transaction_lock);
625 if (copy_from_user(ar->data, buf, size))
626 return ERR_PTR(-EFAULT);
628 return ar->data;
631 ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos)
633 struct simple_transaction_argresp *ar = file->private_data;
635 if (!ar)
636 return 0;
637 return simple_read_from_buffer(buf, size, pos, ar->data, ar->size);
640 int simple_transaction_release(struct inode *inode, struct file *file)
642 free_page((unsigned long)file->private_data);
643 return 0;
646 /* Simple attribute files */
648 struct simple_attr {
649 int (*get)(void *, u64 *);
650 int (*set)(void *, u64);
651 char get_buf[24]; /* enough to store a u64 and "\n\0" */
652 char set_buf[24];
653 void *data;
654 const char *fmt; /* format for read operation */
655 struct mutex mutex; /* protects access to these buffers */
658 /* simple_attr_open is called by an actual attribute open file operation
659 * to set the attribute specific access operations. */
660 int simple_attr_open(struct inode *inode, struct file *file,
661 int (*get)(void *, u64 *), int (*set)(void *, u64),
662 const char *fmt)
664 struct simple_attr *attr;
666 attr = kmalloc(sizeof(*attr), GFP_KERNEL);
667 if (!attr)
668 return -ENOMEM;
670 attr->get = get;
671 attr->set = set;
672 attr->data = inode->i_private;
673 attr->fmt = fmt;
674 mutex_init(&attr->mutex);
676 file->private_data = attr;
678 return nonseekable_open(inode, file);
681 int simple_attr_release(struct inode *inode, struct file *file)
683 kfree(file->private_data);
684 return 0;
687 /* read from the buffer that is filled with the get function */
688 ssize_t simple_attr_read(struct file *file, char __user *buf,
689 size_t len, loff_t *ppos)
691 struct simple_attr *attr;
692 size_t size;
693 ssize_t ret;
695 attr = file->private_data;
697 if (!attr->get)
698 return -EACCES;
700 ret = mutex_lock_interruptible(&attr->mutex);
701 if (ret)
702 return ret;
704 if (*ppos) { /* continued read */
705 size = strlen(attr->get_buf);
706 } else { /* first read */
707 u64 val;
708 ret = attr->get(attr->data, &val);
709 if (ret)
710 goto out;
712 size = scnprintf(attr->get_buf, sizeof(attr->get_buf),
713 attr->fmt, (unsigned long long)val);
716 ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size);
717 out:
718 mutex_unlock(&attr->mutex);
719 return ret;
722 /* interpret the buffer as a number to call the set function with */
723 ssize_t simple_attr_write(struct file *file, const char __user *buf,
724 size_t len, loff_t *ppos)
726 struct simple_attr *attr;
727 u64 val;
728 size_t size;
729 ssize_t ret;
731 attr = file->private_data;
732 if (!attr->set)
733 return -EACCES;
735 ret = mutex_lock_interruptible(&attr->mutex);
736 if (ret)
737 return ret;
739 ret = -EFAULT;
740 size = min(sizeof(attr->set_buf) - 1, len);
741 if (copy_from_user(attr->set_buf, buf, size))
742 goto out;
744 attr->set_buf[size] = '\0';
745 val = simple_strtol(attr->set_buf, NULL, 0);
746 ret = attr->set(attr->data, val);
747 if (ret == 0)
748 ret = len; /* on success, claim we got the whole input */
749 out:
750 mutex_unlock(&attr->mutex);
751 return ret;
755 * generic_fh_to_dentry - generic helper for the fh_to_dentry export operation
756 * @sb: filesystem to do the file handle conversion on
757 * @fid: file handle to convert
758 * @fh_len: length of the file handle in bytes
759 * @fh_type: type of file handle
760 * @get_inode: filesystem callback to retrieve inode
762 * This function decodes @fid as long as it has one of the well-known
763 * Linux filehandle types and calls @get_inode on it to retrieve the
764 * inode for the object specified in the file handle.
766 struct dentry *generic_fh_to_dentry(struct super_block *sb, struct fid *fid,
767 int fh_len, int fh_type, struct inode *(*get_inode)
768 (struct super_block *sb, u64 ino, u32 gen))
770 struct inode *inode = NULL;
772 if (fh_len < 2)
773 return NULL;
775 switch (fh_type) {
776 case FILEID_INO32_GEN:
777 case FILEID_INO32_GEN_PARENT:
778 inode = get_inode(sb, fid->i32.ino, fid->i32.gen);
779 break;
782 return d_obtain_alias(inode);
784 EXPORT_SYMBOL_GPL(generic_fh_to_dentry);
787 * generic_fh_to_dentry - generic helper for the fh_to_parent export operation
788 * @sb: filesystem to do the file handle conversion on
789 * @fid: file handle to convert
790 * @fh_len: length of the file handle in bytes
791 * @fh_type: type of file handle
792 * @get_inode: filesystem callback to retrieve inode
794 * This function decodes @fid as long as it has one of the well-known
795 * Linux filehandle types and calls @get_inode on it to retrieve the
796 * inode for the _parent_ object specified in the file handle if it
797 * is specified in the file handle, or NULL otherwise.
799 struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid,
800 int fh_len, int fh_type, struct inode *(*get_inode)
801 (struct super_block *sb, u64 ino, u32 gen))
803 struct inode *inode = NULL;
805 if (fh_len <= 2)
806 return NULL;
808 switch (fh_type) {
809 case FILEID_INO32_GEN_PARENT:
810 inode = get_inode(sb, fid->i32.parent_ino,
811 (fh_len > 3 ? fid->i32.parent_gen : 0));
812 break;
815 return d_obtain_alias(inode);
817 EXPORT_SYMBOL_GPL(generic_fh_to_parent);
819 int simple_fsync(struct file *file, struct dentry *dentry, int datasync)
821 struct writeback_control wbc = {
822 .sync_mode = WB_SYNC_ALL,
823 .nr_to_write = 0, /* metadata-only; caller takes care of data */
825 struct inode *inode = dentry->d_inode;
826 int err;
827 int ret;
829 ret = sync_mapping_buffers(inode->i_mapping);
830 if (!(inode->i_state & I_DIRTY))
831 return ret;
832 if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
833 return ret;
835 err = sync_inode(inode, &wbc);
836 if (ret == 0)
837 ret = err;
838 return ret;
840 EXPORT_SYMBOL(simple_fsync);
842 EXPORT_SYMBOL(dcache_dir_close);
843 EXPORT_SYMBOL(dcache_dir_lseek);
844 EXPORT_SYMBOL(dcache_dir_open);
845 EXPORT_SYMBOL(dcache_readdir);
846 EXPORT_SYMBOL(generic_read_dir);
847 EXPORT_SYMBOL(get_sb_pseudo);
848 EXPORT_SYMBOL(simple_write_begin);
849 EXPORT_SYMBOL(simple_write_end);
850 EXPORT_SYMBOL(simple_dir_inode_operations);
851 EXPORT_SYMBOL(simple_dir_operations);
852 EXPORT_SYMBOL(simple_empty);
853 EXPORT_SYMBOL(simple_fill_super);
854 EXPORT_SYMBOL(simple_getattr);
855 EXPORT_SYMBOL(simple_link);
856 EXPORT_SYMBOL(simple_lookup);
857 EXPORT_SYMBOL(simple_pin_fs);
858 EXPORT_SYMBOL(simple_readpage);
859 EXPORT_SYMBOL(simple_release_fs);
860 EXPORT_SYMBOL(simple_rename);
861 EXPORT_SYMBOL(simple_rmdir);
862 EXPORT_SYMBOL(simple_statfs);
863 EXPORT_SYMBOL(simple_sync_file);
864 EXPORT_SYMBOL(simple_unlink);
865 EXPORT_SYMBOL(simple_read_from_buffer);
866 EXPORT_SYMBOL(memory_read_from_buffer);
867 EXPORT_SYMBOL(simple_transaction_set);
868 EXPORT_SYMBOL(simple_transaction_get);
869 EXPORT_SYMBOL(simple_transaction_read);
870 EXPORT_SYMBOL(simple_transaction_release);
871 EXPORT_SYMBOL_GPL(simple_attr_open);
872 EXPORT_SYMBOL_GPL(simple_attr_release);
873 EXPORT_SYMBOL_GPL(simple_attr_read);
874 EXPORT_SYMBOL_GPL(simple_attr_write);