/* Copy a page from "oldmem". For this page, there is no pte mapped in the current kernel. We stitch up a pte, similar to kmap_atomic.  */
ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf)
/* Copy a page from "oldmem". For this page, there is no pte mapped in the current kernel. We stitch up a pte, similar to kmap_atomic.  */
ssize_t copy_oldmem_page(unsigned long pfn, char *buf, size_t csize, unsigned long offset, int userbuf)
{
	void  *vaddr;
	if (!csize)
		return 0;
	csize = min(csize, PAGE_SIZE);
	if (pfn < max_pfn) {
		vaddr = __va(pfn << PAGE_SHIFT);
		csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf);
	} else {
		vaddr = __ioremap(pfn << PAGE_SHIFT, PAGE_SIZE, 0);
		csize = copy_oldmem_vaddr(vaddr, buf, csize, offset, userbuf);
		iounmap(vaddr);
	}
	return csize;
}