X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fxen%2Fbiomerge.c;fp=kernel%2Fdrivers%2Fxen%2Fbiomerge.c;h=0edb91c0de6bf2b69d6de3ec41d43d38b5d823b5;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git

diff --git a/kernel/drivers/xen/biomerge.c b/kernel/drivers/xen/biomerge.c
new file mode 100644
index 000000000..0edb91c0d
--- /dev/null
+++ b/kernel/drivers/xen/biomerge.c
@@ -0,0 +1,15 @@
+#include <linux/bio.h>
+#include <linux/io.h>
+#include <linux/export.h>
+#include <xen/page.h>
+
+bool xen_biovec_phys_mergeable(const struct bio_vec *vec1,
+			       const struct bio_vec *vec2)
+{
+	unsigned long mfn1 = pfn_to_mfn(page_to_pfn(vec1->bv_page));
+	unsigned long mfn2 = pfn_to_mfn(page_to_pfn(vec2->bv_page));
+
+	return __BIOVEC_PHYS_MERGEABLE(vec1, vec2) &&
+		((mfn1 == mfn2) || ((mfn1+1) == mfn2));
+}
+EXPORT_SYMBOL(xen_biovec_phys_mergeable);