1// SPDX-License-Identifier: GPL-2.0
2#include <linux/bio.h>
3#include <linux/export.h>
4#include <xen/xen.h>
5#include <xen/page.h>
6
7/* check if @page can be merged with 'vec1' */
8bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
9			       const struct page *page)
10{
11#if XEN_PAGE_SIZE == PAGE_SIZE
12	unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page));
13	unsigned long bfn2 = pfn_to_bfn(page_to_pfn(page));
14
15	return bfn1 + PFN_DOWN(vec1->bv_offset + vec1->bv_len) == bfn2;
16#else
17	/*
18	 * XXX: Add support for merging bio_vec when using different page
19	 * size in Xen and Linux.
20	 */
21	return false;
22#endif
23}
24