Index: xen-3.3.1-testing/tools/blktap/drivers/blktapctrl.c
===================================================================
--- xen-3.3.1-testing.orig/tools/blktap/drivers/blktapctrl.c
+++ xen-3.3.1-testing/tools/blktap/drivers/blktapctrl.c
@@ -65,6 +65,8 @@
 #define MAX_RAND_VAL 0xFFFF
 #define MAX_ATTEMPTS 10
 
+#undef ALWAYS_USE_IOEMU
+
 int run = 1;
 int max_timeout = MAX_TIMEOUT;
 int ctlfd = 0;
@@ -174,7 +176,10 @@ static int test_path(char *path, char **
                         }
 
 			if (found) {
-				*type = dtypes[i]->idnum;
+				if (dtypes[i]->use_ioemu)
+					*type = DISK_TYPE_IOEMU;
+				else
+					*type = dtypes[i]->idnum;
                         
                         if (dtypes[i]->single_handler == 1) {
                                 /* Check whether tapdisk process 
@@ -474,6 +479,7 @@ static int launch_tapdisk_provider(char 
 	return child;
 }
 
+#ifndef ALWAYS_USE_IOEMU
 static int launch_tapdisk(char *wrctldev, char *rdctldev)
 {
 	char *argv[] = { "tapdisk", wrctldev, rdctldev, NULL };
@@ -483,6 +489,7 @@ static int launch_tapdisk(char *wrctldev
 
 	return 0;
 }
+#endif
 
 static int launch_tapdisk_ioemu(void)
 {
@@ -554,6 +561,7 @@ static int connect_qemu(blkif_t *blkif, 
 	return 0;
 }
 
+#ifndef ALWAYS_USE_IOEMU
 /* Launch tapdisk instance */
 static int connect_tapdisk(blkif_t *blkif, int minor)
 {
@@ -597,6 +605,7 @@ fail:
 
 	return ret;
 }
+#endif
 
 static int blktapctrl_new_blkif(blkif_t *blkif)
 {
@@ -621,6 +630,10 @@ static int blktapctrl_new_blkif(blkif_t 
 		blkif->cookie = next_cookie++;
 
 		if (!exist) {
+#ifdef ALWAYS_USE_IOEMU
+			if (connect_qemu(blkif, blkif->domid))
+				goto fail;
+#else
 			if (type == DISK_TYPE_IOEMU) {
 				if (connect_qemu(blkif, blkif->domid))
 					goto fail;
@@ -628,6 +641,7 @@ static int blktapctrl_new_blkif(blkif_t 
 				if (connect_tapdisk(blkif, minor))
 					goto fail;
 			}
+#endif
 
 		} else {
 			DPRINTF("Process exists!\n");
Index: xen-3.3.1-testing/tools/blktap/drivers/tapdisk.h
===================================================================
--- xen-3.3.1-testing.orig/tools/blktap/drivers/tapdisk.h
+++ xen-3.3.1-testing/tools/blktap/drivers/tapdisk.h
@@ -145,6 +145,8 @@ typedef struct disk_info {
 	char handle[10];     /* xend handle, e.g. 'ram' */
 	int  single_handler; /* is there a single controller for all */
 	                     /* instances of disk type? */
+	int  use_ioemu;      /* backend provider: 0 = tapdisk; 1 = ioemu */
+
 #ifdef TAPDISK
 	struct tap_disk *drv;	
 #endif
@@ -166,6 +168,7 @@ static disk_info_t aio_disk = {
 	"raw image (aio)",
 	"aio",
 	0,
+	1,
 #ifdef TAPDISK
 	&tapdisk_aio,
 #endif
@@ -176,6 +179,7 @@ static disk_info_t sync_disk = {
 	"raw image (sync)",
 	"sync",
 	0,
+	1,
 #ifdef TAPDISK
 	&tapdisk_sync,
 #endif
@@ -186,6 +190,7 @@ static disk_info_t vmdk_disk = {
 	"vmware image (vmdk)",
 	"vmdk",
 	1,
+	1,
 #ifdef TAPDISK
 	&tapdisk_vmdk,
 #endif
@@ -196,6 +201,7 @@ static disk_info_t ram_disk = {
 	"ramdisk image (ram)",
 	"ram",
 	1,
+	0,
 #ifdef TAPDISK
 	&tapdisk_ram,
 #endif
@@ -206,6 +212,7 @@ static disk_info_t qcow_disk = {
 	"qcow disk (qcow)",
 	"qcow",
 	0,
+	1,
 #ifdef TAPDISK
 	&tapdisk_qcow,
 #endif
@@ -216,6 +223,7 @@ static disk_info_t qcow2_disk = {
 	"qcow2 disk (qcow2)",
 	"qcow2",
 	0,
+	1,
 #ifdef TAPDISK
 	&tapdisk_qcow2,
 #endif
@@ -226,6 +234,7 @@ static disk_info_t ioemu_disk = {
 	"ioemu disk",
 	"ioemu",
 	1,
+	1,
 #ifdef TAPDISK
 	NULL
 #endif