xref: /openbmc/linux/drivers/xen/biomerge.c (revision a99237af)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bio.h>
3 #include <linux/io.h>
4 #include <linux/export.h>
5 #include <xen/page.h>
6 
7 bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
8 			       const struct bio_vec *vec2)
9 {
10 #if XEN_PAGE_SIZE == PAGE_SIZE
11 	unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page));
12 	unsigned long bfn2 = pfn_to_bfn(page_to_pfn(vec2->bv_page));
13 
14 	return bfn1 + PFN_DOWN(vec1->bv_offset + vec1->bv_len) == bfn2;
15 #else
16 	/*
17 	 * XXX: Add support for merging bio_vec when using different page
18 	 * size in Xen and Linux.
19 	 */
20 	return false;
21 #endif
22 }
23 EXPORT_SYMBOL(xen_biovec_phys_mergeable);
24