1 #include <linux/bio.h> 2 #include <linux/io.h> 3 #include <linux/export.h> 4 #include <xen/page.h> 5 6 bool xen_biovec_phys_mergeable(const struct bio_vec *vec1, 7 const struct bio_vec *vec2) 8 { 9 #if XEN_PAGE_SIZE == PAGE_SIZE 10 unsigned long bfn1 = pfn_to_bfn(page_to_pfn(vec1->bv_page)); 11 unsigned long bfn2 = pfn_to_bfn(page_to_pfn(vec2->bv_page)); 12 13 return bfn1 + PFN_DOWN(vec1->bv_offset + vec1->bv_len) == bfn2; 14 #else 15 /* 16 * XXX: Add support for merging bio_vec when using different page 17 * size in Xen and Linux. 18 */ 19 return 0; 20 #endif 21 } 22 EXPORT_SYMBOL(xen_biovec_phys_mergeable); 23