zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/drivers/xen/biomerge.c b/ap/os/linux/linux-3.4.x/drivers/xen/biomerge.c
new file mode 100644
index 0000000..0edb91c
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/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);