drivers/xen/biomerge.c

   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' */
   8 bool 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 }