Description: fix build failure with Linux kernel >= 3.4
Author: Dmitry Shachnev <mitya57@ubuntu.com>
Bug-Ubuntu: https://bugs.launchpad.net/bugs/1157421

--- a/ring.c
+++ b/ring.c
@@ -26,6 +26,8 @@
 #include <linux/poll.h>
 #include <linux/blkdev.h>
 #include <linux/mman.h>
+#include <linux/version.h>
+#include <linux/mm.h>
 
 #include "blktap.h"
 
@@ -203,7 +205,11 @@
 
 	pgoff = 1 + request->usr_idx * BLKTAP_SEGMENT_MAX;
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 4, 0)
 	addr = do_mmap_pgoff(filp, addr, len, prot, flags, pgoff);
+#else
+	addr = vm_mmap(filp, addr, len, prot, flags, pgoff);
+#endif
 
 	return IS_ERR_VALUE(addr) ? addr : 0;
 }
@@ -223,7 +229,11 @@
 	addr  = MMAP_VADDR(ring->user_vstart, request->usr_idx, 0);
 	len   = request->nr_pages << PAGE_SHIFT;
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(3, 4, 0)
 	err = do_munmap(current->mm, addr, len);
+#else
+	err = vm_munmap(addr, len);
+#endif
 	WARN_ON_ONCE(err);
 }