*/
#include <linux/mm.h>
+#include <linux/err.h>
static unsigned long kernel_virtual_offset;
static int is_xencomm_initialized;
/* We assume the page is modified. */
page = follow_page(vma, vaddr, FOLL_WRITE | FOLL_TOUCH);
- if (!page)
+ if (IS_ERR_OR_NULL(page))
return ~0UL;
return (page_to_pfn(page) << PAGE_SHIFT) | (vaddr & ~PAGE_MASK);