.llseek         = generic_file_llseek,
        .read           = do_sync_read,
        .aio_read       = generic_file_aio_read,
+       .splice_read    = generic_file_splice_read,
        .write          = btrfs_file_write,
        .mmap           = btrfs_file_mmap,
        .open           = generic_file_open,
 
 int btrfs_commit_write(struct file *file, struct page *page,
                       unsigned from, unsigned to)
 {
-       return extent_commit_write(&BTRFS_I(page->mapping->host)->extent_tree,
-                                  page->mapping->host, page, from, to);
+       loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
+       struct inode *inode = page->mapping->host;
+
+       btrfs_cow_one_page(inode, page, PAGE_CACHE_SIZE);
+
+       set_page_extent_mapped(page);
+       set_page_dirty(page);
+
+       if (pos > inode->i_size) {
+               i_size_write(inode, pos);
+               mark_inode_dirty(inode);
+       }
+       return 0;
 }
 
 static int create_subvol(struct btrfs_root *root, char *name, int namelen)