/* simple commit_write call, set_range_dirty is used to mark both the pages and the extent records as dirty  */
int extent_commit_write(struct extent_io_tree *tree, struct inode *inode, struct page *page, unsigned from, unsigned to)
/* simple commit_write call, set_range_dirty is used to mark both the pages and the extent records as dirty  */
int extent_commit_write(struct extent_io_tree *tree, struct inode *inode, struct page *page, unsigned from, unsigned to)
{
	loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
	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;
}