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 0; 21 #endif 22 } 23 EXPORT_SYMBOL(xen_biovec_phys_mergeable); 24