dma-buf: minor documentation fixes.
[linux-2.6.git] / fs / libfs.c
index 892d41c..18d08f5 100644 (file)
@@ -3,15 +3,26 @@
  *     Library for filesystems writers.
  */
 
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/pagemap.h>
+#include <linux/slab.h>
 #include <linux/mount.h>
 #include <linux/vfs.h>
+#include <linux/quotaops.h>
 #include <linux/mutex.h>
 #include <linux/exportfs.h>
+#include <linux/writeback.h>
+#include <linux/buffer_head.h> /* sync_mapping_buffers */
 
 #include <asm/uaccess.h>
 
+#include "internal.h"
+
+static inline int simple_positive(struct dentry *dentry)
+{
+       return dentry->d_inode && !d_unhashed(dentry);
+}
+
 int simple_getattr(struct vfsmount *mnt, struct dentry *dentry,
                   struct kstat *stat)
 {
@@ -33,7 +44,7 @@ int simple_statfs(struct dentry *dentry, struct kstatfs *buf)
  * Retaining negative dentries for an in-memory filesystem just wastes
  * memory and lookup time: arrange for them to be deleted immediately.
  */
-static int simple_delete_dentry(struct dentry *dentry)
+static int simple_delete_dentry(const struct dentry *dentry)
 {
        return 1;
 }
@@ -44,22 +55,17 @@ static int simple_delete_dentry(struct dentry *dentry)
  */
 struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 {
-       static struct dentry_operations simple_dentry_operations = {
+       static const struct dentry_operations simple_dentry_operations = {
                .d_delete = simple_delete_dentry,
        };
 
        if (dentry->d_name.len > NAME_MAX)
                return ERR_PTR(-ENAMETOOLONG);
-       dentry->d_op = &simple_dentry_operations;
+       d_set_d_op(dentry, &simple_dentry_operations);
        d_add(dentry, NULL);
        return NULL;
 }
 
-int simple_sync_file(struct file * file, struct dentry *dentry, int datasync)
-{
-       return 0;
-}
 int dcache_dir_open(struct inode *inode, struct file *file)
 {
        static struct qstr cursor_name = {.len = 1, .name = "."};
@@ -77,7 +83,8 @@ int dcache_dir_close(struct inode *inode, struct file *file)
 
 loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin)
 {
-       mutex_lock(&file->f_path.dentry->d_inode->i_mutex);
+       struct dentry *dentry = file->f_path.dentry;
+       mutex_lock(&dentry->d_inode->i_mutex);
        switch (origin) {
                case 1:
                        offset += file->f_pos;
@@ -85,7 +92,7 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin)
                        if (offset >= 0)
                                break;
                default:
-                       mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
+                       mutex_unlock(&dentry->d_inode->i_mutex);
                        return -EINVAL;
        }
        if (offset != file->f_pos) {
@@ -95,21 +102,24 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin)
                        struct dentry *cursor = file->private_data;
                        loff_t n = file->f_pos - 2;
 
-                       spin_lock(&dcache_lock);
+                       spin_lock(&dentry->d_lock);
+                       /* d_lock not required for cursor */
                        list_del(&cursor->d_u.d_child);
-                       p = file->f_path.dentry->d_subdirs.next;
-                       while (n && p != &file->f_path.dentry->d_subdirs) {
+                       p = dentry->d_subdirs.next;
+                       while (n && p != &dentry->d_subdirs) {
                                struct dentry *next;
                                next = list_entry(p, struct dentry, d_u.d_child);
-                               if (!d_unhashed(next) && next->d_inode)
+                               spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
+                               if (simple_positive(next))
                                        n--;
+                               spin_unlock(&next->d_lock);
                                p = p->next;
                        }
                        list_add_tail(&cursor->d_u.d_child, p);
-                       spin_unlock(&dcache_lock);
+                       spin_unlock(&dentry->d_lock);
                }
        }
-       mutex_unlock(&file->f_path.dentry->d_inode->i_mutex);
+       mutex_unlock(&dentry->d_inode->i_mutex);
        return offset;
 }
 
@@ -149,29 +159,35 @@ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir)
                        i++;
                        /* fallthrough */
                default:
-                       spin_lock(&dcache_lock);
+                       spin_lock(&dentry->d_lock);
                        if (filp->f_pos == 2)
                                list_move(q, &dentry->d_subdirs);
 
                        for (p=q->next; p != &dentry->d_subdirs; p=p->next) {
                                struct dentry *next;
                                next = list_entry(p, struct dentry, d_u.d_child);
-                               if (d_unhashed(next) || !next->d_inode)
+                               spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
+                               if (!simple_positive(next)) {
+                                       spin_unlock(&next->d_lock);
                                        continue;
+                               }
 
-                               spin_unlock(&dcache_lock);
+                               spin_unlock(&next->d_lock);
+                               spin_unlock(&dentry->d_lock);
                                if (filldir(dirent, next->d_name.name, 
                                            next->d_name.len, filp->f_pos, 
                                            next->d_inode->i_ino, 
                                            dt_type(next->d_inode)) < 0)
                                        return 0;
-                               spin_lock(&dcache_lock);
+                               spin_lock(&dentry->d_lock);
+                               spin_lock_nested(&next->d_lock, DENTRY_D_LOCK_NESTED);
                                /* next is still alive */
                                list_move(q, p);
+                               spin_unlock(&next->d_lock);
                                p = q;
                                filp->f_pos++;
                        }
-                       spin_unlock(&dcache_lock);
+                       spin_unlock(&dentry->d_lock);
        }
        return 0;
 }
@@ -187,7 +203,7 @@ const struct file_operations simple_dir_operations = {
        .llseek         = dcache_dir_lseek,
        .read           = generic_read_dir,
        .readdir        = dcache_readdir,
-       .fsync          = simple_sync_file,
+       .fsync          = noop_fsync,
 };
 
 const struct inode_operations simple_dir_inode_operations = {
@@ -202,9 +218,9 @@ static const struct super_operations simple_super_operations = {
  * Common helper for pseudo-filesystems (sockfs, pipefs, bdev - stuff that
  * will never be mountable)
  */
-int get_sb_pseudo(struct file_system_type *fs_type, char *name,
-       const struct super_operations *ops, unsigned long magic,
-       struct vfsmount *mnt)
+struct dentry *mount_pseudo(struct file_system_type *fs_type, char *name,
+       const struct super_operations *ops,
+       const struct dentry_operations *dops, unsigned long magic)
 {
        struct super_block *s = sget(fs_type, NULL, set_anon_super, NULL);
        struct dentry *dentry;
@@ -212,12 +228,12 @@ int get_sb_pseudo(struct file_system_type *fs_type, char *name,
        struct qstr d_name = {.name = name, .len = strlen(name)};
 
        if (IS_ERR(s))
-               return PTR_ERR(s);
+               return ERR_CAST(s);
 
        s->s_flags = MS_NOUSER;
-       s->s_maxbytes = ~0ULL;
-       s->s_blocksize = 1024;
-       s->s_blocksize_bits = 10;
+       s->s_maxbytes = MAX_LFS_FILESIZE;
+       s->s_blocksize = PAGE_SIZE;
+       s->s_blocksize_bits = PAGE_SHIFT;
        s->s_magic = magic;
        s->s_op = ops ? ops : &simple_super_operations;
        s->s_time_gran = 1;
@@ -231,24 +247,28 @@ int get_sb_pseudo(struct file_system_type *fs_type, char *name,
         */
        root->i_ino = 1;
        root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR;
-       root->i_uid = root->i_gid = 0;
        root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME;
-       dentry = d_alloc(NULL, &d_name);
+       dentry = __d_alloc(s, &d_name);
        if (!dentry) {
                iput(root);
                goto Enomem;
        }
-       dentry->d_sb = s;
-       dentry->d_parent = dentry;
        d_instantiate(dentry, root);
        s->s_root = dentry;
+       s->s_d_op = dops;
        s->s_flags |= MS_ACTIVE;
-       return simple_set_mnt(mnt, s);
+       return dget(s->s_root);
 
 Enomem:
-       up_write(&s->s_umount);
-       deactivate_super(s);
-       return -ENOMEM;
+       deactivate_locked_super(s);
+       return ERR_PTR(-ENOMEM);
+}
+
+int simple_open(struct inode *inode, struct file *file)
+{
+       if (inode->i_private)
+               file->private_data = inode->i_private;
+       return 0;
 }
 
 int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
@@ -257,29 +277,29 @@ int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *den
 
        inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME;
        inc_nlink(inode);
-       atomic_inc(&inode->i_count);
+       ihold(inode);
        dget(dentry);
        d_instantiate(dentry, inode);
        return 0;
 }
 
-static inline int simple_positive(struct dentry *dentry)
-{
-       return dentry->d_inode && !d_unhashed(dentry);
-}
-
 int simple_empty(struct dentry *dentry)
 {
        struct dentry *child;
        int ret = 0;
 
-       spin_lock(&dcache_lock);
-       list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child)
-               if (simple_positive(child))
+       spin_lock(&dentry->d_lock);
+       list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) {
+               spin_lock_nested(&child->d_lock, DENTRY_D_LOCK_NESTED);
+               if (simple_positive(child)) {
+                       spin_unlock(&child->d_lock);
                        goto out;
+               }
+               spin_unlock(&child->d_lock);
+       }
        ret = 1;
 out:
-       spin_unlock(&dcache_lock);
+       spin_unlock(&dentry->d_lock);
        return ret;
 }
 
@@ -315,8 +335,10 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
 
        if (new_dentry->d_inode) {
                simple_unlink(new_dir, new_dentry);
-               if (they_are_dirs)
+               if (they_are_dirs) {
+                       drop_nlink(new_dentry->d_inode);
                        drop_nlink(old_dir);
+               }
        } else if (they_are_dirs) {
                drop_nlink(old_dir);
                inc_nlink(new_dir);
@@ -328,6 +350,39 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry,
        return 0;
 }
 
+/**
+ * simple_setattr - setattr for simple filesystem
+ * @dentry: dentry
+ * @iattr: iattr structure
+ *
+ * Returns 0 on success, -error on failure.
+ *
+ * simple_setattr is a simple ->setattr implementation without a proper
+ * implementation of size changes.
+ *
+ * It can either be used for in-memory filesystems or special files
+ * on simple regular filesystems.  Anything that needs to change on-disk
+ * or wire state on size changes needs its own setattr method.
+ */
+int simple_setattr(struct dentry *dentry, struct iattr *iattr)
+{
+       struct inode *inode = dentry->d_inode;
+       int error;
+
+       WARN_ON_ONCE(inode->i_op->truncate);
+
+       error = inode_change_ok(inode, iattr);
+       if (error)
+               return error;
+
+       if (iattr->ia_valid & ATTR_SIZE)
+               truncate_setsize(inode, iattr->ia_size);
+       setattr_copy(inode, iattr);
+       mark_inode_dirty(inode);
+       return 0;
+}
+EXPORT_SYMBOL(simple_setattr);
+
 int simple_readpage(struct file *file, struct page *page)
 {
        clear_highpage(page);
@@ -337,72 +392,74 @@ int simple_readpage(struct file *file, struct page *page)
        return 0;
 }
 
-int simple_prepare_write(struct file *file, struct page *page,
-                       unsigned from, unsigned to)
-{
-       if (!PageUptodate(page)) {
-               if (to - from != PAGE_CACHE_SIZE)
-                       zero_user_segments(page,
-                               0, from,
-                               to, PAGE_CACHE_SIZE);
-       }
-       return 0;
-}
-
 int simple_write_begin(struct file *file, struct address_space *mapping,
                        loff_t pos, unsigned len, unsigned flags,
                        struct page **pagep, void **fsdata)
 {
        struct page *page;
        pgoff_t index;
-       unsigned from;
 
        index = pos >> PAGE_CACHE_SHIFT;
-       from = pos & (PAGE_CACHE_SIZE - 1);
 
-       page = __grab_cache_page(mapping, index);
+       page = grab_cache_page_write_begin(mapping, index, flags);
        if (!page)
                return -ENOMEM;
 
        *pagep = page;
 
-       return simple_prepare_write(file, page, from, from+len);
-}
+       if (!PageUptodate(page) && (len != PAGE_CACHE_SIZE)) {
+               unsigned from = pos & (PAGE_CACHE_SIZE - 1);
 
-static int simple_commit_write(struct file *file, struct page *page,
-                              unsigned from, unsigned to)
-{
-       struct inode *inode = page->mapping->host;
-       loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
-
-       if (!PageUptodate(page))
-               SetPageUptodate(page);
-       /*
-        * No need to use i_size_read() here, the i_size
-        * cannot change under us because we hold the i_mutex.
-        */
-       if (pos > inode->i_size)
-               i_size_write(inode, pos);
-       set_page_dirty(page);
+               zero_user_segments(page, 0, from, from + len, PAGE_CACHE_SIZE);
+       }
        return 0;
 }
 
+/**
+ * simple_write_end - .write_end helper for non-block-device FSes
+ * @available: See .write_end of address_space_operations
+ * @file:              "
+ * @mapping:           "
+ * @pos:               "
+ * @len:               "
+ * @copied:            "
+ * @page:              "
+ * @fsdata:            "
+ *
+ * simple_write_end does the minimum needed for updating a page after writing is
+ * done. It has the same API signature as the .write_end of
+ * address_space_operations vector. So it can just be set onto .write_end for
+ * FSes that don't need any other processing. i_mutex is assumed to be held.
+ * Block based filesystems should use generic_write_end().
+ * NOTE: Even though i_size might get updated by this function, mark_inode_dirty
+ * is not called, so a filesystem that actually does store data in .write_inode
+ * should extend on what's done here with a call to mark_inode_dirty() in the
+ * case that i_size has changed.
+ */
 int simple_write_end(struct file *file, struct address_space *mapping,
                        loff_t pos, unsigned len, unsigned copied,
                        struct page *page, void *fsdata)
 {
-       unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+       struct inode *inode = page->mapping->host;
+       loff_t last_pos = pos + copied;
 
        /* zero the stale part of the page if we did a short copy */
        if (copied < len) {
-               void *kaddr = kmap_atomic(page, KM_USER0);
-               memset(kaddr + from + copied, 0, len - copied);
-               flush_dcache_page(page);
-               kunmap_atomic(kaddr, KM_USER0);
+               unsigned from = pos & (PAGE_CACHE_SIZE - 1);
+
+               zero_user(page, from + copied, len - copied);
        }
 
-       simple_commit_write(file, page, from, from+copied);
+       if (!PageUptodate(page))
+               SetPageUptodate(page);
+       /*
+        * No need to use i_size_read() here, the i_size
+        * cannot change under us because we hold the i_mutex.
+        */
+       if (last_pos > inode->i_size)
+               i_size_write(inode, last_pos);
 
+       set_page_dirty(page);
        unlock_page(page);
        page_cache_release(page);
 
@@ -414,7 +471,8 @@ int simple_write_end(struct file *file, struct address_space *mapping,
  * unique inode values later for this filesystem, then you must take care
  * to pass it an appropriate max_reserved value to avoid collisions.
  */
-int simple_fill_super(struct super_block *s, int magic, struct tree_descr *files)
+int simple_fill_super(struct super_block *s, unsigned long magic,
+                     struct tree_descr *files)
 {
        struct inode *inode;
        struct dentry *root;
@@ -436,17 +494,13 @@ int simple_fill_super(struct super_block *s, int magic, struct tree_descr *files
         */
        inode->i_ino = 1;
        inode->i_mode = S_IFDIR | 0755;
-       inode->i_uid = inode->i_gid = 0;
-       inode->i_blocks = 0;
        inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
        inode->i_op = &simple_dir_inode_operations;
        inode->i_fop = &simple_dir_operations;
-       inode->i_nlink = 2;
-       root = d_alloc_root(inode);
-       if (!root) {
-               iput(inode);
+       set_nlink(inode, 2);
+       root = d_make_root(inode);
+       if (!root)
                return -ENOMEM;
-       }
        for (i = 0; !files->name || files->name[0]; i++, files++) {
                if (!files->name)
                        continue;
@@ -461,11 +515,11 @@ int simple_fill_super(struct super_block *s, int magic, struct tree_descr *files
                if (!dentry)
                        goto out;
                inode = new_inode(s);
-               if (!inode)
+               if (!inode) {
+                       dput(dentry);
                        goto out;
+               }
                inode->i_mode = S_IFREG | files->mode;
-               inode->i_uid = inode->i_gid = 0;
-               inode->i_blocks = 0;
                inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
                inode->i_fop = files->ops;
                inode->i_ino = i;
@@ -475,6 +529,7 @@ int simple_fill_super(struct super_block *s, int magic, struct tree_descr *files
        return 0;
 out:
        d_genocide(root);
+       shrink_dcache_parent(root);
        dput(root);
        return -ENOMEM;
 }
@@ -487,7 +542,7 @@ int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *c
        spin_lock(&pin_fs_lock);
        if (unlikely(!*mount)) {
                spin_unlock(&pin_fs_lock);
-               mnt = vfs_kern_mount(type, 0, type->name, NULL);
+               mnt = vfs_kern_mount(type, MS_KERNMOUNT, type->name, NULL);
                if (IS_ERR(mnt))
                        return PTR_ERR(mnt);
                spin_lock(&pin_fs_lock);
@@ -512,22 +567,88 @@ void simple_release_fs(struct vfsmount **mount, int *count)
        mntput(mnt);
 }
 
+/**
+ * simple_read_from_buffer - copy data from the buffer to user space
+ * @to: the user space buffer to read to
+ * @count: the maximum number of bytes to read
+ * @ppos: the current position in the buffer
+ * @from: the buffer to read from
+ * @available: the size of the buffer
+ *
+ * The simple_read_from_buffer() function reads up to @count bytes from the
+ * buffer @from at offset @ppos into the user space address starting at @to.
+ *
+ * On success, the number of bytes read is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
 ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos,
                                const void *from, size_t available)
 {
        loff_t pos = *ppos;
+       size_t ret;
+
        if (pos < 0)
                return -EINVAL;
-       if (pos >= available)
+       if (pos >= available || !count)
                return 0;
        if (count > available - pos)
                count = available - pos;
-       if (copy_to_user(to, from + pos, count))
+       ret = copy_to_user(to, from + pos, count);
+       if (ret == count)
                return -EFAULT;
+       count -= ret;
        *ppos = pos + count;
        return count;
 }
 
+/**
+ * simple_write_to_buffer - copy data from user space to the buffer
+ * @to: the buffer to write to
+ * @available: the size of the buffer
+ * @ppos: the current position in the buffer
+ * @from: the user space buffer to read from
+ * @count: the maximum number of bytes to read
+ *
+ * The simple_write_to_buffer() function reads up to @count bytes from the user
+ * space address starting at @from into the buffer @to at offset @ppos.
+ *
+ * On success, the number of bytes written is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
+ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos,
+               const void __user *from, size_t count)
+{
+       loff_t pos = *ppos;
+       size_t res;
+
+       if (pos < 0)
+               return -EINVAL;
+       if (pos >= available || !count)
+               return 0;
+       if (count > available - pos)
+               count = available - pos;
+       res = copy_from_user(to + pos, from, count);
+       if (res == count)
+               return -EFAULT;
+       count -= res;
+       *ppos = pos + count;
+       return count;
+}
+
+/**
+ * memory_read_from_buffer - copy data from the buffer
+ * @to: the kernel space buffer to read to
+ * @count: the maximum number of bytes to read
+ * @ppos: the current position in the buffer
+ * @from: the buffer to read from
+ * @available: the size of the buffer
+ *
+ * The memory_read_from_buffer() function reads up to @count bytes from the
+ * buffer @from at offset @ppos into the kernel space address starting at @to.
+ *
+ * On success, the number of bytes read is returned and the offset @ppos is
+ * advanced by this number, or negative value is returned on error.
+ **/
 ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
                                const void *from, size_t available)
 {
@@ -551,6 +672,21 @@ ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos,
  * possibly a read which collects the result - which is stored in a
  * file-local buffer.
  */
+
+void simple_transaction_set(struct file *file, size_t n)
+{
+       struct simple_transaction_argresp *ar = file->private_data;
+
+       BUG_ON(n > SIMPLE_TRANSACTION_LIMIT);
+
+       /*
+        * The barrier ensures that ar->size will really remain zero until
+        * ar->data is ready for reading.
+        */
+       smp_mb();
+       ar->size = n;
+}
+
 char *simple_transaction_get(struct file *file, const char __user *buf, size_t size)
 {
        struct simple_transaction_argresp *ar;
@@ -695,37 +831,16 @@ ssize_t simple_attr_write(struct file *file, const char __user *buf,
        if (copy_from_user(attr->set_buf, buf, size))
                goto out;
 
-       ret = len; /* claim we got the whole input */
        attr->set_buf[size] = '\0';
-       val = simple_strtol(attr->set_buf, NULL, 0);
-       attr->set(attr->data, val);
+       val = simple_strtoll(attr->set_buf, NULL, 0);
+       ret = attr->set(attr->data, val);
+       if (ret == 0)
+               ret = len; /* on success, claim we got the whole input */
 out:
        mutex_unlock(&attr->mutex);
        return ret;
 }
 
-/*
- * This is what d_alloc_anon should have been.  Once the exportfs
- * argument transition has been finished I will update d_alloc_anon
- * to this prototype and this wrapper will go away.   --hch
- */
-static struct dentry *exportfs_d_alloc(struct inode *inode)
-{
-       struct dentry *dentry;
-
-       if (!inode)
-               return NULL;
-       if (IS_ERR(inode))
-               return ERR_PTR(PTR_ERR(inode));
-
-       dentry = d_alloc_anon(inode);
-       if (!dentry) {
-               iput(inode);
-               dentry = ERR_PTR(-ENOMEM);
-       }
-       return dentry;
-}
-
 /**
  * generic_fh_to_dentry - generic helper for the fh_to_dentry export operation
  * @sb:                filesystem to do the file handle conversion on
@@ -754,7 +869,7 @@ struct dentry *generic_fh_to_dentry(struct super_block *sb, struct fid *fid,
                break;
        }
 
-       return exportfs_d_alloc(inode);
+       return d_obtain_alias(inode);
 }
 EXPORT_SYMBOL_GPL(generic_fh_to_dentry);
 
@@ -787,37 +902,111 @@ struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid,
                break;
        }
 
-       return exportfs_d_alloc(inode);
+       return d_obtain_alias(inode);
 }
 EXPORT_SYMBOL_GPL(generic_fh_to_parent);
 
+/**
+ * generic_file_fsync - generic fsync implementation for simple filesystems
+ * @file:      file to synchronize
+ * @datasync:  only synchronize essential metadata if true
+ *
+ * This is a generic implementation of the fsync method for simple
+ * filesystems which track all non-inode metadata in the buffers list
+ * hanging off the address_space structure.
+ */
+int generic_file_fsync(struct file *file, loff_t start, loff_t end,
+                      int datasync)
+{
+       struct inode *inode = file->f_mapping->host;
+       int err;
+       int ret;
+
+       err = filemap_write_and_wait_range(inode->i_mapping, start, end);
+       if (err)
+               return err;
+
+       mutex_lock(&inode->i_mutex);
+       ret = sync_mapping_buffers(inode->i_mapping);
+       if (!(inode->i_state & I_DIRTY))
+               goto out;
+       if (datasync && !(inode->i_state & I_DIRTY_DATASYNC))
+               goto out;
+
+       err = sync_inode_metadata(inode, 1);
+       if (ret == 0)
+               ret = err;
+out:
+       mutex_unlock(&inode->i_mutex);
+       return ret;
+}
+EXPORT_SYMBOL(generic_file_fsync);
+
+/**
+ * generic_check_addressable - Check addressability of file system
+ * @blocksize_bits:    log of file system block size
+ * @num_blocks:                number of blocks in file system
+ *
+ * Determine whether a file system with @num_blocks blocks (and a
+ * block size of 2**@blocksize_bits) is addressable by the sector_t
+ * and page cache of the system.  Return 0 if so and -EFBIG otherwise.
+ */
+int generic_check_addressable(unsigned blocksize_bits, u64 num_blocks)
+{
+       u64 last_fs_block = num_blocks - 1;
+       u64 last_fs_page =
+               last_fs_block >> (PAGE_CACHE_SHIFT - blocksize_bits);
+
+       if (unlikely(num_blocks == 0))
+               return 0;
+
+       if ((blocksize_bits < 9) || (blocksize_bits > PAGE_CACHE_SHIFT))
+               return -EINVAL;
+
+       if ((last_fs_block > (sector_t)(~0ULL) >> (blocksize_bits - 9)) ||
+           (last_fs_page > (pgoff_t)(~0ULL))) {
+               return -EFBIG;
+       }
+       return 0;
+}
+EXPORT_SYMBOL(generic_check_addressable);
+
+/*
+ * No-op implementation of ->fsync for in-memory filesystems.
+ */
+int noop_fsync(struct file *file, loff_t start, loff_t end, int datasync)
+{
+       return 0;
+}
+
 EXPORT_SYMBOL(dcache_dir_close);
 EXPORT_SYMBOL(dcache_dir_lseek);
 EXPORT_SYMBOL(dcache_dir_open);
 EXPORT_SYMBOL(dcache_readdir);
 EXPORT_SYMBOL(generic_read_dir);
-EXPORT_SYMBOL(get_sb_pseudo);
+EXPORT_SYMBOL(mount_pseudo);
 EXPORT_SYMBOL(simple_write_begin);
 EXPORT_SYMBOL(simple_write_end);
 EXPORT_SYMBOL(simple_dir_inode_operations);
 EXPORT_SYMBOL(simple_dir_operations);
 EXPORT_SYMBOL(simple_empty);
-EXPORT_SYMBOL(d_alloc_name);
 EXPORT_SYMBOL(simple_fill_super);
 EXPORT_SYMBOL(simple_getattr);
+EXPORT_SYMBOL(simple_open);
 EXPORT_SYMBOL(simple_link);
 EXPORT_SYMBOL(simple_lookup);
 EXPORT_SYMBOL(simple_pin_fs);
-EXPORT_SYMBOL(simple_prepare_write);
 EXPORT_SYMBOL(simple_readpage);
 EXPORT_SYMBOL(simple_release_fs);
 EXPORT_SYMBOL(simple_rename);
 EXPORT_SYMBOL(simple_rmdir);
 EXPORT_SYMBOL(simple_statfs);
-EXPORT_SYMBOL(simple_sync_file);
+EXPORT_SYMBOL(noop_fsync);
 EXPORT_SYMBOL(simple_unlink);
 EXPORT_SYMBOL(simple_read_from_buffer);
+EXPORT_SYMBOL(simple_write_to_buffer);
 EXPORT_SYMBOL(memory_read_from_buffer);
+EXPORT_SYMBOL(simple_transaction_set);
 EXPORT_SYMBOL(simple_transaction_get);
 EXPORT_SYMBOL(simple_transaction_read);
 EXPORT_SYMBOL(simple_transaction_release);