datapath-windows: Add GRE TEB support for windows datapath
[cascardo/ovs.git] / datapath-windows / ovsext / Vport.c
index 68755b9..7b0103d 100644 (file)
  */
 
 #include "precomp.h"
+
+#include "Datapath.h"
+#include "Event.h"
+#include "Gre.h"
+#include "IpHelper.h"
 #include "Jhash.h"
+#include "Oid.h"
+#include "Stt.h"
 #include "Switch.h"
-#include "Vport.h"
-#include "Event.h"
 #include "User.h"
+#include "Vport.h"
 #include "Vxlan.h"
-#include "IpHelper.h"
-#include "Oid.h"
-#include "Datapath.h"
 
 #ifdef OVS_DBG_MOD
 #undef OVS_DBG_MOD
 
 #define OVS_VPORT_DEFAULT_WAIT_TIME_MICROSEC    100
 
+/* Context structure used to pass back and forth information to the tunnel
+ * filter threads. */
+typedef struct _OVS_TUNFLT_INIT_CONTEXT {
+    POVS_SWITCH_CONTEXT switchContext;
+    UINT32 outputLength;
+    PVOID outputBuffer;
+    PVOID inputBuffer;
+    POVS_VPORT_ENTRY vport;
+    BOOLEAN hvSwitchPort;
+    BOOLEAN hvDelete;
+    BOOLEAN ovsDelete;
+} OVS_TUNFLT_INIT_CONTEXT, *POVS_TUNFLT_INIT_CONTEXT;
+
+
 extern POVS_SWITCH_CONTEXT gOvsSwitchContext;
-extern PNDIS_SPIN_LOCK gOvsCtrlLock;
 
 static VOID OvsInitVportWithPortParam(POVS_VPORT_ENTRY vport,
                 PNDIS_SWITCH_PORT_PARAMETERS portParam);
 static VOID OvsInitVportWithNicParam(POVS_SWITCH_CONTEXT switchContext,
                 POVS_VPORT_ENTRY vport, PNDIS_SWITCH_NIC_PARAMETERS nicParam);
-static VOID OvsInitPhysNicVport(POVS_VPORT_ENTRY physExtVPort,
-                POVS_VPORT_ENTRY virtExtVport, UINT32 nicIndex);
+static VOID OvsCopyPortParamsFromVport(POVS_VPORT_ENTRY vport,
+                                       PNDIS_SWITCH_PORT_PARAMETERS portParam);
 static __inline VOID OvsWaitActivate(POVS_SWITCH_CONTEXT switchContext,
                                      ULONG sleepMicroSec);
 static NTSTATUS OvsGetExtInfoIoctl(POVS_VPORT_GET vportGet,
@@ -65,36 +81,97 @@ static NTSTATUS CreateNetlinkMesgForNetdev(POVS_VPORT_EXT_INFO info,
                                            PVOID outBuffer,
                                            UINT32 outBufLen,
                                            int dpIfIndex);
+static POVS_VPORT_ENTRY OvsFindVportByHvNameW(POVS_SWITCH_CONTEXT switchContext,
+                                              PWSTR wsName, SIZE_T wstrSize);
+static VOID UpdateSwitchCtxWithVport(POVS_SWITCH_CONTEXT switchContext,
+                                     POVS_VPORT_ENTRY vport, BOOLEAN newPort);
+static NTSTATUS OvsRemoveTunnelVport(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                                     POVS_SWITCH_CONTEXT switchContext,
+                                     POVS_VPORT_ENTRY vport,
+                                     BOOLEAN hvDelete,
+                                     BOOLEAN ovsDelete);
+static VOID OvsTunnelVportPendingInit(PVOID context,
+                                      NTSTATUS status,
+                                      UINT32 *replyLen);
+static VOID OvsTunnelVportPendingRemove(PVOID context,
+                                        NTSTATUS status,
+                                        UINT32 *replyLen);
+static NTSTATUS GetNICAlias(GUID *netCfgInstanceId,
+                            IF_COUNTED_STRING *portFriendlyName);
 
 /*
- * Functions implemented in relaton to NDIS port manipulation.
+ * --------------------------------------------------------------------------
+ *  Creates a Vport entry for a Hyper-V switch port. 'nicIndex' is typically
+ *  associated with a NIC than a port. We use it here for the special case
+ *  where we need to create a Vport for an external NIC with NicIndex > 0.
+ * --------------------------------------------------------------------------
  */
 NDIS_STATUS
 HvCreatePort(POVS_SWITCH_CONTEXT switchContext,
-             PNDIS_SWITCH_PORT_PARAMETERS portParam)
+             PNDIS_SWITCH_PORT_PARAMETERS portParam,
+             NDIS_SWITCH_NIC_INDEX nicIndex)
 {
     POVS_VPORT_ENTRY vport;
     LOCK_STATE_EX lockState;
     NDIS_STATUS status = NDIS_STATUS_SUCCESS;
+    BOOLEAN newPort = FALSE;
 
     VPORT_PORT_ENTER(portParam);
 
     NdisAcquireRWLockWrite(switchContext->dispatchLock, &lockState, 0);
+    /* Lookup by port ID. */
     vport = OvsFindVportByPortIdAndNicIndex(switchContext,
-                                            portParam->PortId, 0);
-    if (vport != NULL && !vport->hvDeleted) {
+                                            portParam->PortId, nicIndex);
+    if (vport != NULL) {
+        OVS_LOG_ERROR("Port add failed due to duplicate port name, "
+                      "port Id: %u", portParam->PortId);
+        status = STATUS_DATA_NOT_ACCEPTED;
+        goto create_port_done;
+    }
+
+    /*
+     * Lookup by port name to see if this port with this name had been added
+     * (and deleted) previously.
+     */
+    vport = OvsFindVportByHvNameW(gOvsSwitchContext,
+                                  portParam->PortFriendlyName.String,
+                                  portParam->PortFriendlyName.Length);
+    if (vport && vport->isAbsentOnHv == FALSE) {
+        OVS_LOG_ERROR("Port add failed since a port already exists on "
+                      "the specified port Id: %u, ovsName: %s",
+                      portParam->PortId, vport->ovsName);
         status = STATUS_DATA_NOT_ACCEPTED;
         goto create_port_done;
-    } else if (!vport) {
+    }
+
+    if (vport != NULL) {
+        ASSERT(vport->isAbsentOnHv);
+        ASSERT(vport->portNo != OVS_DPPORT_NUMBER_INVALID);
+
+        /*
+         * It should be possible to simply just mark this port as "not deleted"
+         * given that the port Id and the name are the same and also provided
+         * that the other properties that we cache have not changed.
+         */
+        if (vport->portType != portParam->PortType) {
+            OVS_LOG_INFO("Port add failed due to PortType change, port Id: %u"
+                         " old: %u, new: %u", portParam->PortId,
+                         vport->portType, portParam->PortType);
+            status = STATUS_DATA_NOT_ACCEPTED;
+            goto create_port_done;
+        }
+        vport->isAbsentOnHv = FALSE;
+    } else {
         vport = (POVS_VPORT_ENTRY)OvsAllocateVport();
         if (vport == NULL) {
             status = NDIS_STATUS_RESOURCES;
             goto create_port_done;
         }
+        newPort = TRUE;
     }
-
     OvsInitVportWithPortParam(vport, portParam);
-    InitHvVportCommon(switchContext, vport);
+    vport->nicIndex = nicIndex;
+    UpdateSwitchCtxWithVport(switchContext, vport, newPort);
 
 create_port_done:
     NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
@@ -104,7 +181,9 @@ create_port_done:
 
 
 /*
- * Function updating the port properties
+ * --------------------------------------------------------------------------
+ * Function to process updates to a port on the Hyper-Vs witch.
+ * --------------------------------------------------------------------------
  */
 NDIS_STATUS
 HvUpdatePort(POVS_SWITCH_CONTEXT switchContext,
@@ -122,17 +201,15 @@ HvUpdatePort(POVS_SWITCH_CONTEXT switchContext,
                                             portParam->PortId, 0);
     /*
      * Update properties only for NETDEV ports for supprting PS script
-     * We don't allow changing the names of the internal or external ports
      */
-    if (vport == NULL || ( vport->portType != NdisSwitchPortTypeSynthetic) || 
-        ( vport->portType != NdisSwitchPortTypeEmulated)) {
+    if (vport == NULL) {
         goto update_port_done;
     }
 
     /* Store the nic and the OVS states as Nic Create won't be called */
     ovsState = vport->ovsState;
     nicState = vport->nicState;
-    
+
     /*
      * Currently only the port friendly name is being updated
      * Make sure that no other properties are changed
@@ -159,6 +236,12 @@ update_port_done:
     return NDIS_STATUS_SUCCESS;
 }
 
+
+/*
+ * --------------------------------------------------------------------------
+ * Function to process teardown of a port on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 VOID
 HvTeardownPort(POVS_SWITCH_CONTEXT switchContext,
                PNDIS_SWITCH_PORT_PARAMETERS portParam)
@@ -172,8 +255,7 @@ HvTeardownPort(POVS_SWITCH_CONTEXT switchContext,
     vport = OvsFindVportByPortIdAndNicIndex(switchContext,
                                             portParam->PortId, 0);
     if (vport) {
-        /* add assertion here
-         */
+        /* add assertion here */
         vport->portState = NdisSwitchPortStateTeardown;
         vport->ovsState = OVS_STATE_PORT_TEAR_DOWN;
     } else {
@@ -184,8 +266,11 @@ HvTeardownPort(POVS_SWITCH_CONTEXT switchContext,
     VPORT_PORT_EXIT(portParam);
 }
 
-
-
+/*
+ * --------------------------------------------------------------------------
+ * Function to process deletion of a port on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 VOID
 HvDeletePort(POVS_SWITCH_CONTEXT switchContext,
              PNDIS_SWITCH_PORT_PARAMETERS portParams)
@@ -206,11 +291,7 @@ HvDeletePort(POVS_SWITCH_CONTEXT switchContext,
      * delete will delete the vport.
     */
     if (vport) {
-        if (vport->portNo == OVS_DPPORT_NUMBER_INVALID) {
-            OvsRemoveAndDeleteVport(switchContext, vport);
-        } else {
-            vport->hvDeleted = TRUE;
-        }
+        OvsRemoveAndDeleteVport(NULL, switchContext, vport, TRUE, FALSE);
     } else {
         OVS_LOG_WARN("Vport not present.");
     }
@@ -221,17 +302,19 @@ HvDeletePort(POVS_SWITCH_CONTEXT switchContext,
 
 
 /*
- * Functions implemented in relaton to NDIS NIC manipulation.
+ * --------------------------------------------------------------------------
+ * Function to process addition of a NIC connection on the Hyper-V switch.
+ * XXX: Posting an event to DPIF is incorrect here. However, it might be useful
+ * to post an event to netdev-windows.c.
+ * --------------------------------------------------------------------------
  */
 NDIS_STATUS
 HvCreateNic(POVS_SWITCH_CONTEXT switchContext,
             PNDIS_SWITCH_NIC_PARAMETERS nicParam)
 {
     POVS_VPORT_ENTRY vport;
-    UINT32 portNo = 0;
-    UINT32 event = 0;
     NDIS_STATUS status = NDIS_STATUS_SUCCESS;
-
+    IF_COUNTED_STRING portFriendlyName = {0};
     LOCK_STATE_EX lockState;
 
     VPORT_NIC_ENTER(nicParam);
@@ -246,46 +329,54 @@ HvCreateNic(POVS_SWITCH_CONTEXT switchContext,
         goto done;
     }
 
-    NdisAcquireRWLockWrite(switchContext->dispatchLock, &lockState, 0);
-    vport = OvsFindVportByPortIdAndNicIndex(switchContext, nicParam->PortId, 0);
-    if (vport == NULL) {
-        OVS_LOG_ERROR("Create NIC without Switch Port,"
-                      " PortId: %x, NicIndex: %d",
-                      nicParam->PortId, nicParam->NicIndex);
-        status = NDIS_STATUS_INVALID_PARAMETER;
-        goto add_nic_done;
+    if (OvsIsInternalNIC(nicParam->NicType) ||
+        OvsIsRealExternalNIC(nicParam->NicType, nicParam->NicIndex)) {
+        GetNICAlias(&nicParam->NetCfgInstanceId, &portFriendlyName);
     }
 
-    if (nicParam->NicType == NdisSwitchNicTypeExternal &&
-        nicParam->NicIndex != 0) {
+    NdisAcquireRWLockWrite(switchContext->dispatchLock, &lockState, 0);
+    /*
+     * There can be one or more NICs for the external port. We create a vport
+     * structure for each such NIC, and each NIC inherits a lot of properties
+     * from the parent external port.
+     */
+    if (OvsIsRealExternalNIC(nicParam->NicType, nicParam->NicIndex)) {
+        NDIS_SWITCH_PORT_PARAMETERS portParam;
         POVS_VPORT_ENTRY virtExtVport =
             (POVS_VPORT_ENTRY)switchContext->virtualExternalVport;
 
-        vport = (POVS_VPORT_ENTRY)OvsAllocateVport();
-        if (vport == NULL) {
-            status = NDIS_STATUS_RESOURCES;
-            goto add_nic_done;
-        }
-        OvsInitPhysNicVport(vport, virtExtVport, nicParam->NicIndex);
-        status = InitHvVportCommon(switchContext, vport);
+        ASSERT(virtExtVport);
+        ASSERT(OvsFindVportByPortIdAndNicIndex(switchContext,
+                                               nicParam->PortId,
+                                               nicParam->NicIndex) == NULL);
+        OvsCopyPortParamsFromVport(virtExtVport, &portParam);
+        NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
+        status = HvCreatePort(switchContext, &portParam,
+                              nicParam->NicIndex);
+        NdisAcquireRWLockWrite(switchContext->dispatchLock, &lockState, 0);
         if (status != NDIS_STATUS_SUCCESS) {
-            OvsFreeMemory(vport);
             goto add_nic_done;
         }
     }
+
+    vport = OvsFindVportByPortIdAndNicIndex(switchContext, nicParam->PortId,
+                                            nicParam->NicIndex);
+    if (vport == NULL) {
+        OVS_LOG_ERROR("Create NIC without Switch Port,"
+                      " PortId: %x, NicIndex: %d",
+                      nicParam->PortId, nicParam->NicIndex);
+        status = NDIS_STATUS_INVALID_PARAMETER;
+        goto add_nic_done;
+    }
     OvsInitVportWithNicParam(switchContext, vport, nicParam);
-    portNo = vport->portNo;
-    if (vport->ovsState == OVS_STATE_CONNECTED) {
-        event = OVS_EVENT_CONNECT | OVS_EVENT_LINK_UP;
-    } else if (vport->ovsState == OVS_STATE_NIC_CREATED) {
-        event = OVS_EVENT_CONNECT;
+    if (OvsIsInternalNIC(nicParam->NicType) ||
+        OvsIsRealExternalNIC(nicParam->NicType, nicParam->NicIndex)) {
+        RtlCopyMemory(&vport->portFriendlyName, &portFriendlyName,
+                      sizeof portFriendlyName);
     }
 
 add_nic_done:
     NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
-    if (portNo != OVS_DPPORT_NUMBER_INVALID && event) {
-        OvsPostEvent(portNo, event);
-    }
 
 done:
     VPORT_NIC_EXIT(nicParam);
@@ -294,15 +385,18 @@ done:
     return status;
 }
 
-
-/* Mark already created NIC as connected. */
+/*
+ * --------------------------------------------------------------------------
+ * Function to process connection event of a NIC on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 VOID
 HvConnectNic(POVS_SWITCH_CONTEXT switchContext,
              PNDIS_SWITCH_NIC_PARAMETERS nicParam)
 {
     LOCK_STATE_EX lockState;
     POVS_VPORT_ENTRY vport;
-    UINT32 portNo = 0;
+    UINT32 portNo;
 
     VPORT_NIC_ENTER(nicParam);
 
@@ -332,25 +426,30 @@ HvConnectNic(POVS_SWITCH_CONTEXT switchContext,
 
     NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
 
-    /* XXX only if portNo != INVALID or always? */
-    OvsPostEvent(portNo, OVS_EVENT_LINK_UP);
-
     if (nicParam->NicType == NdisSwitchNicTypeInternal) {
-        OvsInternalAdapterUp(portNo, &nicParam->NetCfgInstanceId);
+        OvsInternalAdapterUp(&nicParam->NetCfgInstanceId);
     }
 
 done:
     VPORT_NIC_EXIT(nicParam);
 }
 
+
+/*
+ * --------------------------------------------------------------------------
+ * Function to process updates to a NIC on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 VOID
 HvUpdateNic(POVS_SWITCH_CONTEXT switchContext,
             PNDIS_SWITCH_NIC_PARAMETERS nicParam)
 {
     POVS_VPORT_ENTRY vport;
     LOCK_STATE_EX lockState;
-
-    UINT32 status = 0, portNo = 0;
+    UINT32 event = 0;
+    IF_COUNTED_STRING portFriendlyName = {0};
+    BOOLEAN nameChanged = FALSE;
+    BOOLEAN aliasLookup = FALSE;
 
     VPORT_NIC_ENTER(nicParam);
 
@@ -362,11 +461,19 @@ HvUpdateNic(POVS_SWITCH_CONTEXT switchContext,
         goto update_nic_done;
     }
 
+    /* GetNICAlias() must be called outside of a lock. */
+    if (nicParam->NicType == NdisSwitchNicTypeInternal ||
+        OvsIsRealExternalNIC(nicParam->NicType, nicParam->NicIndex)) {
+        GetNICAlias(&nicParam->NetCfgInstanceId, &portFriendlyName);
+        aliasLookup = TRUE;
+    }
+
     NdisAcquireRWLockWrite(switchContext->dispatchLock, &lockState, 0);
     vport = OvsFindVportByPortIdAndNicIndex(switchContext,
                                             nicParam->PortId,
                                             nicParam->NicIndex);
     if (vport == NULL) {
+        NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
         OVS_LOG_WARN("Vport search failed.");
         goto update_nic_done;
     }
@@ -375,12 +482,21 @@ HvUpdateNic(POVS_SWITCH_CONTEXT switchContext,
     case NdisSwitchNicTypeInternal:
         RtlCopyMemory(&vport->netCfgInstanceId, &nicParam->NetCfgInstanceId,
                       sizeof (GUID));
+        if (aliasLookup) {
+            if (RtlCompareMemory(&vport->portFriendlyName,
+                    &portFriendlyName, vport->portFriendlyName.Length) !=
+                    vport->portFriendlyName.Length) {
+                RtlCopyMemory(&vport->portFriendlyName, &portFriendlyName,
+                    sizeof portFriendlyName);
+                nameChanged = TRUE;
+            }
+        }
         break;
     case NdisSwitchNicTypeSynthetic:
     case NdisSwitchNicTypeEmulated:
         if (!RtlEqualMemory(vport->vmMacAddress, nicParam->VMMacAddress,
                            sizeof (vport->vmMacAddress))) {
-            status |= OVS_EVENT_MAC_CHANGE;
+            event |= OVS_EVENT_MAC_CHANGE;
             RtlCopyMemory(vport->vmMacAddress, nicParam->VMMacAddress,
                           sizeof (vport->vmMacAddress));
         }
@@ -392,39 +508,59 @@ HvUpdateNic(POVS_SWITCH_CONTEXT switchContext,
                         sizeof (vport->permMacAddress))) {
         RtlCopyMemory(vport->permMacAddress, nicParam->PermanentMacAddress,
                       sizeof (vport->permMacAddress));
-        status |= OVS_EVENT_MAC_CHANGE;
+        event |= OVS_EVENT_MAC_CHANGE;
     }
     if (!RtlEqualMemory(vport->currMacAddress, nicParam->CurrentMacAddress,
                         sizeof (vport->currMacAddress))) {
         RtlCopyMemory(vport->currMacAddress, nicParam->CurrentMacAddress,
                       sizeof (vport->currMacAddress));
-        status |= OVS_EVENT_MAC_CHANGE;
+        event |= OVS_EVENT_MAC_CHANGE;
     }
 
     if (vport->mtu != nicParam->MTU) {
         vport->mtu = nicParam->MTU;
-        status |= OVS_EVENT_MTU_CHANGE;
+        event |= OVS_EVENT_MTU_CHANGE;
     }
     vport->numaNodeId = nicParam->NumaNodeId;
-    portNo = vport->portNo;
 
-    NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
-    if (status && portNo) {
-        OvsPostEvent(portNo, status);
+    if (nameChanged) {
+        OVS_EVENT_ENTRY event;
+        event.portNo = vport->portNo;
+        event.ovsType = vport->ovsType;
+        event.upcallPid = vport->upcallPid;
+        RtlCopyMemory(&event.ovsName, &vport->ovsName, sizeof event.ovsName);
+        event.type = OVS_EVENT_LINK_DOWN;
+        OvsRemoveAndDeleteVport(NULL, switchContext, vport, FALSE, TRUE);
+        OvsPostEvent(&event);
     }
+
+    NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
+
+    /*
+     * XXX: Not sure what kind of event to post here. DPIF is not interested in
+     * changes to MAC address. Netdev-windows might be intrested, though.
+     * That said, if the name chagnes, not clear what kind of event to be
+     * posted. We might have to delete the vport, and have userspace recreate
+     * it.
+     */
+
 update_nic_done:
     VPORT_NIC_EXIT(nicParam);
 }
 
-
+/*
+ * --------------------------------------------------------------------------
+ * Function to process disconnect event of a NIC on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 VOID
 HvDisconnectNic(POVS_SWITCH_CONTEXT switchContext,
                 PNDIS_SWITCH_NIC_PARAMETERS nicParam)
 {
     POVS_VPORT_ENTRY vport;
-    UINT32 portNo = 0;
     LOCK_STATE_EX lockState;
     BOOLEAN isInternalPort = FALSE;
+    OVS_EVENT_ENTRY event;
 
     VPORT_NIC_ENTER(nicParam);
 
@@ -449,16 +585,26 @@ HvDisconnectNic(POVS_SWITCH_CONTEXT switchContext,
 
     vport->nicState = NdisSwitchNicStateDisconnected;
     vport->ovsState = OVS_STATE_NIC_CREATED;
-    portNo = vport->portNo;
 
     if (vport->ovsType == OVS_VPORT_TYPE_INTERNAL) {
         isInternalPort = TRUE;
     }
 
-    NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
+    event.portNo = vport->portNo;
+    event.ovsType = vport->ovsType;
+    event.upcallPid = vport->upcallPid;
+    RtlCopyMemory(&event.ovsName, &vport->ovsName, sizeof event.ovsName);
+    event.type = OVS_EVENT_LINK_DOWN;
 
-    /* XXX if portNo != INVALID or always? */
-    OvsPostEvent(portNo, OVS_EVENT_LINK_DOWN);
+    /*
+     * Delete the port from the hash tables accessible to userspace. After this
+     * point, userspace should not be able to access this port.
+     */
+    if (OvsIsRealExternalVport(vport)) {
+        OvsRemoveAndDeleteVport(NULL, switchContext, vport, FALSE, TRUE);
+        OvsPostEvent(&event);
+    }
+    NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
 
     if (isInternalPort) {
         OvsInternalAdapterDown();
@@ -468,14 +614,17 @@ done:
     VPORT_NIC_EXIT(nicParam);
 }
 
-
+/*
+ * --------------------------------------------------------------------------
+ * Function to process delete event of a NIC on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 VOID
 HvDeleteNic(POVS_SWITCH_CONTEXT switchContext,
             PNDIS_SWITCH_NIC_PARAMETERS nicParam)
 {
     LOCK_STATE_EX lockState;
     POVS_VPORT_ENTRY vport;
-    UINT32 portNo = 0;
 
     VPORT_NIC_ENTER(nicParam);
     /* Wait for lists to be initialized. */
@@ -497,23 +646,20 @@ HvDeleteNic(POVS_SWITCH_CONTEXT switchContext,
         goto done;
     }
 
-    portNo = vport->portNo;
-    if (vport->portType == NdisSwitchPortTypeExternal &&
-        vport->nicIndex != 0) {
-        OvsRemoveAndDeleteVport(switchContext, vport);
-    }
     vport->nicState = NdisSwitchNicStateUnknown;
     vport->ovsState = OVS_STATE_PORT_CREATED;
 
+    if (OvsIsRealExternalVport(vport)) {
+        /* This vport was created in HvCreateNic(). */
+        OvsRemoveAndDeleteVport(NULL, switchContext, vport, TRUE, FALSE);
+    }
+
     NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
-    /* XXX if portNo != INVALID or always? */
-    OvsPostEvent(portNo, OVS_EVENT_DISCONNECT);
 
 done:
     VPORT_NIC_EXIT(nicParam);
 }
 
-
 /*
  * OVS Vport related functionality.
  */
@@ -536,6 +682,45 @@ OvsFindVportByPortNo(POVS_SWITCH_CONTEXT switchContext,
 }
 
 
+POVS_VPORT_ENTRY
+OvsFindTunnelVportByDstPort(POVS_SWITCH_CONTEXT switchContext,
+                            UINT16 dstPort,
+                            OVS_VPORT_TYPE ovsPortType)
+{
+    POVS_VPORT_ENTRY vport;
+    PLIST_ENTRY head, link;
+    UINT32 hash = OvsJhashBytes((const VOID *)&dstPort, sizeof(dstPort),
+                                OVS_HASH_BASIS);
+    head = &(switchContext->tunnelVportsArray[hash & OVS_VPORT_MASK]);
+    LIST_FORALL(head, link) {
+        vport = CONTAINING_RECORD(link, OVS_VPORT_ENTRY, tunnelVportLink);
+        if (GetPortFromPriv(vport) == dstPort &&
+            vport->ovsType == ovsPortType) {
+            return vport;
+        }
+    }
+    return NULL;
+}
+
+POVS_VPORT_ENTRY
+OvsFindTunnelVportByPortType(POVS_SWITCH_CONTEXT switchContext,
+                             OVS_VPORT_TYPE ovsPortType)
+{
+    POVS_VPORT_ENTRY vport;
+    PLIST_ENTRY head, link;
+    UINT16 dstPort = 0;
+    UINT32 hash = OvsJhashBytes((const VOID *)&dstPort, sizeof(dstPort),
+                                OVS_HASH_BASIS);
+    head = &(switchContext->tunnelVportsArray[hash & OVS_VPORT_MASK]);
+    LIST_FORALL(head, link) {
+        vport = CONTAINING_RECORD(link, OVS_VPORT_ENTRY, tunnelVportLink);
+        if (vport->ovsType == ovsPortType) {
+            return vport;
+        }
+    }
+    return NULL;
+}
+
 POVS_VPORT_ENTRY
 OvsFindVportByOvsName(POVS_SWITCH_CONTEXT switchContext,
                       PSTR name)
@@ -560,24 +745,13 @@ OvsFindVportByOvsName(POVS_SWITCH_CONTEXT switchContext,
 
 /* OvsFindVportByHvName: "name" is assumed to be null-terminated */
 POVS_VPORT_ENTRY
-OvsFindVportByHvName(POVS_SWITCH_CONTEXT switchContext,
-                     PSTR name)
+OvsFindVportByHvNameW(POVS_SWITCH_CONTEXT switchContext,
+                      PWSTR wsName, SIZE_T wstrSize)
 {
     POVS_VPORT_ENTRY vport = NULL;
     PLIST_ENTRY head, link;
-    /* 'portFriendlyName' is not NUL-terminated. */
-    SIZE_T length = strlen(name);
-    SIZE_T wstrSize = length * sizeof(WCHAR);
     UINT i;
 
-    PWSTR wsName = OvsAllocateMemory(wstrSize);
-    if (!wsName) {
-        return NULL;
-    }
-    for (i = 0; i < length; i++) {
-        wsName[i] = name[i];
-    }
-
     for (i = 0; i < OVS_MAX_VPORT_ARRAY_SIZE; i++) {
         head = &(switchContext->portIdHashArray[i]);
         LIST_FORALL(head, link) {
@@ -598,9 +772,49 @@ OvsFindVportByHvName(POVS_SWITCH_CONTEXT switchContext,
         }
     }
 
+    /*
+     * Look in the list of ports that were added from the Hyper-V switch and
+     * deleted.
+     */
+    if (vport == NULL) {
+        for (i = 0; i < OVS_MAX_VPORT_ARRAY_SIZE; i++) {
+            head = &(switchContext->portNoHashArray[i]);
+            LIST_FORALL(head, link) {
+                vport = CONTAINING_RECORD(link, OVS_VPORT_ENTRY, portNoLink);
+                if (vport->portFriendlyName.Length == wstrSize &&
+                    RtlEqualMemory(wsName, vport->portFriendlyName.String,
+                                   vport->portFriendlyName.Length)) {
+                    goto Cleanup;
+                }
+
+                vport = NULL;
+            }
+        }
+    }
+
 Cleanup:
-    OvsFreeMemory(wsName);
+    return vport;
+}
 
+POVS_VPORT_ENTRY
+OvsFindVportByHvNameA(POVS_SWITCH_CONTEXT switchContext,
+                      PSTR name)
+{
+    POVS_VPORT_ENTRY vport = NULL;
+    /* 'portFriendlyName' is not NUL-terminated. */
+    SIZE_T length = strlen(name);
+    SIZE_T wstrSize = length * sizeof(WCHAR);
+    UINT i;
+
+    PWSTR wsName = OvsAllocateMemoryWithTag(wstrSize, OVS_VPORT_POOL_TAG);
+    if (!wsName) {
+        return NULL;
+    }
+    for (i = 0; i < length; i++) {
+        wsName[i] = name[i];
+    }
+    vport = OvsFindVportByHvNameW(switchContext, wsName, wstrSize);
+    OvsFreeMemoryWithTag(wsName, OVS_VPORT_POOL_TAG);
     return vport;
 }
 
@@ -637,13 +851,14 @@ POVS_VPORT_ENTRY
 OvsAllocateVport(VOID)
 {
     POVS_VPORT_ENTRY vport;
-    vport = (POVS_VPORT_ENTRY)OvsAllocateMemory(sizeof (OVS_VPORT_ENTRY));
+    vport = (POVS_VPORT_ENTRY)OvsAllocateMemoryWithTag(
+        sizeof(OVS_VPORT_ENTRY), OVS_VPORT_POOL_TAG);
     if (vport == NULL) {
         return NULL;
     }
     RtlZeroMemory(vport, sizeof (OVS_VPORT_ENTRY));
     vport->ovsState = OVS_STATE_UNKNOWN;
-    vport->hvDeleted = FALSE;
+    vport->isAbsentOnHv = FALSE;
     vport->portNo = OVS_DPPORT_NUMBER_INVALID;
 
     InitializeListHead(&vport->ovsNameLink);
@@ -728,6 +943,7 @@ OvsInitVportWithNicParam(POVS_SWITCH_CONTEXT switchContext,
     vport->mtu = nicParam->MTU;
     vport->nicState = nicParam->NicState;
     vport->nicIndex = nicParam->NicIndex;
+    vport->nicType = nicParam->NicType;
     vport->numaNodeId = nicParam->NumaNodeId;
 
     switch (vport->nicState) {
@@ -748,33 +964,23 @@ OvsInitVportWithNicParam(POVS_SWITCH_CONTEXT switchContext,
 
 /*
  * --------------------------------------------------------------------------
- * Copies the relevant NDIS port properties from a virtual (pseudo) external
- * NIC to a physical (real) external NIC.
+ * Populates 'portParam' based on 'vport'.
  * --------------------------------------------------------------------------
  */
 static VOID
-OvsInitPhysNicVport(POVS_VPORT_ENTRY physExtVport,
-                    POVS_VPORT_ENTRY virtExtVport,
-                    UINT32 physNicIndex)
+OvsCopyPortParamsFromVport(POVS_VPORT_ENTRY vport,
+                           PNDIS_SWITCH_PORT_PARAMETERS portParam)
 {
-    physExtVport->portType = virtExtVport->portType;
-    physExtVport->portState = virtExtVport->portState;
-    physExtVport->portId = virtExtVport->portId;
-    physExtVport->nicState = NdisSwitchNicStateUnknown;
-    physExtVport->ovsType = OVS_VPORT_TYPE_NETDEV;
-    physExtVport->isExternal = TRUE;
-    physExtVport->isBridgeInternal = FALSE;
-    physExtVport->nicIndex = (NDIS_SWITCH_NIC_INDEX)physNicIndex;
-
-    RtlCopyMemory(&physExtVport->hvPortName, &virtExtVport->hvPortName,
+    portParam->Flags = 0;
+    portParam->PortId = vport->portId;
+    RtlCopyMemory(&portParam->PortName, &vport->hvPortName,
                   sizeof (NDIS_SWITCH_PORT_NAME));
-
-    /* 'portFriendlyName' is overwritten later. */
-    RtlCopyMemory(&physExtVport->portFriendlyName,
-                  &virtExtVport->portFriendlyName,
+    RtlCopyMemory(&portParam->PortFriendlyName,
+                  &vport->portFriendlyName,
                   sizeof(NDIS_SWITCH_PORT_FRIENDLYNAME));
-
-    physExtVport->ovsState = OVS_STATE_PORT_CREATED;
+    portParam->PortType = vport->portType;
+    portParam->IsValidationPort = FALSE;
+    portParam->PortState = vport->portState;
 }
 
 /*
@@ -783,22 +989,50 @@ OvsInitPhysNicVport(POVS_VPORT_ENTRY physExtVport,
  * --------------------------------------------------------------------------
  */
 NTSTATUS
-OvsInitTunnelVport(POVS_VPORT_ENTRY vport,
+OvsInitTunnelVport(PVOID userContext,
+                   POVS_VPORT_ENTRY vport,
                    OVS_VPORT_TYPE ovsType,
                    UINT16 dstPort)
 {
     NTSTATUS status = STATUS_SUCCESS;
+    POVS_USER_PARAMS_CONTEXT usrParamsCtx =
+        (POVS_USER_PARAMS_CONTEXT)userContext;
 
     vport->isBridgeInternal = FALSE;
     vport->ovsType = ovsType;
     vport->ovsState = OVS_STATE_PORT_CREATED;
     switch (ovsType) {
     case OVS_VPORT_TYPE_GRE:
-        break;
-    case OVS_VPORT_TYPE_GRE64:
+        status = OvsInitGreTunnel(vport);
         break;
     case OVS_VPORT_TYPE_VXLAN:
-        status = OvsInitVxlanTunnel(vport, dstPort);
+    {
+        POVS_TUNFLT_INIT_CONTEXT tunnelContext = NULL;
+
+        tunnelContext = OvsAllocateMemoryWithTag(sizeof(*tunnelContext),
+                                                 OVS_VPORT_POOL_TAG);
+        if (tunnelContext == NULL) {
+            status = STATUS_INSUFFICIENT_RESOURCES;
+            break;
+        }
+        tunnelContext->inputBuffer = usrParamsCtx->inputBuffer;
+        tunnelContext->outputBuffer = usrParamsCtx->outputBuffer;
+        tunnelContext->outputLength = usrParamsCtx->outputLength;
+        tunnelContext->vport = vport;
+
+        status = OvsInitVxlanTunnel(usrParamsCtx->irp,
+                                    vport,
+                                    dstPort,
+                                    OvsTunnelVportPendingInit,
+                                    (PVOID)tunnelContext);
+        if (status != STATUS_PENDING) {
+            OvsFreeMemoryWithTag(tunnelContext, OVS_VPORT_POOL_TAG);
+            tunnelContext = NULL;
+        }
+        break;
+    }
+    case OVS_VPORT_TYPE_STT:
+        status = OvsInitSttTunnel(vport, dstPort);
         break;
     default:
         ASSERT(0);
@@ -825,36 +1059,44 @@ OvsInitBridgeInternalVport(POVS_VPORT_ENTRY vport)
 
 /*
  * --------------------------------------------------------------------------
- * For external vports 'portFriendlyName' provided by Hyper-V is over-written
- * by synthetic names.
+ * For external and internal vports 'portFriendlyName' parameter, provided by
+ * Hyper-V, is overwritten with the interface alias name.
  * --------------------------------------------------------------------------
  */
-static VOID
-AssignNicNameSpecial(POVS_VPORT_ENTRY vport)
+static NTSTATUS
+GetNICAlias(GUID *netCfgInstanceId,
+            IF_COUNTED_STRING *portFriendlyName)
 {
-    size_t len;
+    NTSTATUS status = STATUS_SUCCESS;
+    WCHAR interfaceName[IF_MAX_STRING_SIZE] = { 0 };
+    NET_LUID interfaceLuid = { 0 };
+    size_t len = 0;
 
-    if (vport->portType == NdisSwitchPortTypeExternal) {
-        if (vport->nicIndex == 0) {
-            ASSERT(vport->nicIndex == 0);
-            RtlStringCbPrintfW(vport->portFriendlyName.String,
-                               IF_MAX_STRING_SIZE,
-                               L"%s.virtualAdapter", OVS_DPPORT_EXTERNAL_NAME_W);
+    status = ConvertInterfaceGuidToLuid(netCfgInstanceId,
+                                        &interfaceLuid);
+    if (status == STATUS_SUCCESS) {
+        /*
+         * Must be called from PASSIVE_LEVEL. Resulted in a
+         * STATUS_INVALID_DEVICE_REQUEST if not.
+         */
+        status = ConvertInterfaceLuidToAlias(&interfaceLuid, interfaceName,
+                                             IF_MAX_STRING_SIZE + 1);
+        if (status == STATUS_SUCCESS) {
+            RtlStringCbPrintfW(portFriendlyName->String,
+                               IF_MAX_STRING_SIZE, L"%s", interfaceName);
+            RtlStringCbLengthW(portFriendlyName->String, IF_MAX_STRING_SIZE,
+                               &len);
+            portFriendlyName->Length = (USHORT)len;
         } else {
-            RtlStringCbPrintfW(vport->portFriendlyName.String,
-                               IF_MAX_STRING_SIZE,
-                               L"%s.%lu", OVS_DPPORT_EXTERNAL_NAME_W,
-                               (UINT32)vport->nicIndex);
+            OVS_LOG_ERROR("Fail to convert interface LUID to alias, status: %x",
+                status);
         }
     } else {
-        RtlStringCbPrintfW(vport->portFriendlyName.String,
-                           IF_MAX_STRING_SIZE,
-                           L"%s", OVS_DPPORT_INTERNAL_NAME_W);
+        OVS_LOG_ERROR("Fail to convert interface GUID to LUID, status: %x",
+                      status);
     }
 
-    RtlStringCbLengthW(vport->portFriendlyName.String, IF_MAX_STRING_SIZE,
-                       &len);
-    vport->portFriendlyName.Length = (USHORT)len;
+    return status;
 }
 
 
@@ -865,26 +1107,17 @@ AssignNicNameSpecial(POVS_VPORT_ENTRY vport)
  *
  * Inserts the port into 'portIdHashArray' and caches the pointer in the
  * 'switchContext' if needed.
- *
- * For external NIC, assigns the name for the NIC.
  * --------------------------------------------------------------------------
  */
-NDIS_STATUS
-InitHvVportCommon(POVS_SWITCH_CONTEXT switchContext,
-                  POVS_VPORT_ENTRY vport)
+static VOID
+UpdateSwitchCtxWithVport(POVS_SWITCH_CONTEXT switchContext,
+                         POVS_VPORT_ENTRY vport,
+                         BOOLEAN newPort)
 {
     UINT32 hash;
-    ASSERT(vport->portNo == OVS_DPPORT_NUMBER_INVALID);
 
     switch (vport->portType) {
     case NdisSwitchPortTypeExternal:
-        /*
-         * Overwrite the 'portFriendlyName' of this external vport. The reason
-         * for having this in common code is to be able to call it from the NDIS
-         * Port callback as well as the NDIS NIC callback.
-         */
-        AssignNicNameSpecial(vport);
-
         if (vport->nicIndex == 0) {
             switchContext->virtualExternalPortId = vport->portId;
             switchContext->virtualExternalVport = vport;
@@ -894,9 +1127,6 @@ InitHvVportCommon(POVS_SWITCH_CONTEXT switchContext,
         break;
     case NdisSwitchPortTypeInternal:
         ASSERT(vport->isBridgeInternal == FALSE);
-
-        /* Overwrite the 'portFriendlyName' of the internal vport. */
-        AssignNicNameSpecial(vport);
         switchContext->internalPortId = vport->portId;
         switchContext->internalVport = vport;
         break;
@@ -912,7 +1142,7 @@ InitHvVportCommon(POVS_SWITCH_CONTEXT switchContext,
      */
     if (vport->portType == NdisSwitchPortTypeExternal &&
         vport->nicIndex == 0) {
-        return NDIS_STATUS_SUCCESS;
+        return;
     }
 
     /*
@@ -923,16 +1153,18 @@ InitHvVportCommon(POVS_SWITCH_CONTEXT switchContext,
     hash = OvsJhashWords(&vport->portId, 1, OVS_HASH_BASIS);
     InsertHeadList(&switchContext->portIdHashArray[hash & OVS_VPORT_MASK],
                    &vport->portIdLink);
-    switchContext->numHvVports++;
-    return NDIS_STATUS_SUCCESS;
+    if (newPort) {
+        switchContext->numHvVports++;
+    }
+    return;
 }
 
 /*
  * --------------------------------------------------------------------------
  * Functionality common to any port added from OVS userspace.
  *
- * Inserts the port into 'portIdHashArray', 'ovsPortNameHashArray' and caches
- * the pointer in the 'switchContext' if needed.
+ * Inserts the port into 'portNoHashArray', 'ovsPortNameHashArray' and in
+ * 'tunnelVportsArray' if appropriate.
  * --------------------------------------------------------------------------
  */
 NDIS_STATUS
@@ -942,11 +1174,20 @@ InitOvsVportCommon(POVS_SWITCH_CONTEXT switchContext,
     UINT32 hash;
 
     switch(vport->ovsType) {
+    case OVS_VPORT_TYPE_GRE:
     case OVS_VPORT_TYPE_VXLAN:
-        ASSERT(switchContext->vxlanVport == NULL);
-        switchContext->vxlanVport = vport;
+    case OVS_VPORT_TYPE_STT:
+    {
+        UINT16 dstPort = GetPortFromPriv(vport);
+        hash = OvsJhashBytes(&dstPort,
+                             sizeof(dstPort),
+                             OVS_HASH_BASIS);
+        InsertHeadList(
+            &gOvsSwitchContext->tunnelVportsArray[hash & OVS_VPORT_MASK],
+            &vport->tunnelVportLink);
         switchContext->numNonHvVports++;
         break;
+    }
     case OVS_VPORT_TYPE_INTERNAL:
         if (vport->isBridgeInternal) {
             switchContext->numNonHvVports++;
@@ -967,8 +1208,9 @@ InitOvsVportCommon(POVS_SWITCH_CONTEXT switchContext,
 
     hash = OvsJhashBytes(vport->ovsName, strlen(vport->ovsName) + 1,
                          OVS_HASH_BASIS);
-    InsertHeadList(&gOvsSwitchContext->ovsPortNameHashArray[hash & OVS_VPORT_MASK],
-                   &vport->ovsNameLink);
+    InsertHeadList(
+        &gOvsSwitchContext->ovsPortNameHashArray[hash & OVS_VPORT_MASK],
+        &vport->ovsNameLink);
 
     return STATUS_SUCCESS;
 }
@@ -977,73 +1219,182 @@ InitOvsVportCommon(POVS_SWITCH_CONTEXT switchContext,
 /*
  * --------------------------------------------------------------------------
  * Provides functionality that is partly complementatry to
- * InitOvsVportCommon()/InitHvVportCommon().
+ * InitOvsVportCommon()/UpdateSwitchCtxWithVport().
+ *
+ * 'hvDelete' indicates if caller is removing the vport as a result of the
+ * port being removed on the Hyper-V switch.
+ * 'ovsDelete' indicates if caller is removing the vport as a result of the
+ * port being removed from OVS userspace.
  * --------------------------------------------------------------------------
  */
-VOID
-OvsRemoveAndDeleteVport(POVS_SWITCH_CONTEXT switchContext,
-                        POVS_VPORT_ENTRY vport)
+NTSTATUS
+OvsRemoveAndDeleteVport(PVOID usrParamsContext,
+                        POVS_SWITCH_CONTEXT switchContext,
+                        POVS_VPORT_ENTRY vport,
+                        BOOLEAN hvDelete,
+                        BOOLEAN ovsDelete)
 {
+    POVS_USER_PARAMS_CONTEXT usrParamsCtx =
+        (POVS_USER_PARAMS_CONTEXT)usrParamsContext;
     BOOLEAN hvSwitchPort = FALSE;
-
-    if (vport->isExternal) {
-        if (vport->nicIndex == 0) {
-            ASSERT(switchContext->numPhysicalNics == 0);
-            switchContext->virtualExternalPortId = 0;
-            switchContext->virtualExternalVport = NULL;
-            OvsFreeMemory(vport);
-            return;
-        } else {
-            ASSERT(switchContext->numPhysicalNics);
-            switchContext->numPhysicalNics--;
-            hvSwitchPort = TRUE;
-        }
-    }
+    BOOLEAN deletedOnOvs = FALSE;
+    BOOLEAN deletedOnHv = FALSE;
 
     switch (vport->ovsType) {
     case OVS_VPORT_TYPE_INTERNAL:
         if (!vport->isBridgeInternal) {
-            switchContext->internalPortId = 0;
-            switchContext->internalVport = NULL;
-            OvsInternalAdapterDown();
+            if (hvDelete && vport->isAbsentOnHv == FALSE) {
+                switchContext->internalPortId = 0;
+                switchContext->internalVport = NULL;
+                OvsInternalAdapterDown();
+            }
             hvSwitchPort = TRUE;
         }
         break;
     case OVS_VPORT_TYPE_VXLAN:
-        OvsCleanupVxlanTunnel(vport);
-        switchContext->vxlanVport = NULL;
+    {
+        NTSTATUS status;
+        status = OvsRemoveTunnelVport(usrParamsCtx, switchContext, vport,
+                                      hvDelete, ovsDelete);
+        if (status != STATUS_SUCCESS) {
+            return status;
+        }
+    }
+    case OVS_VPORT_TYPE_STT:
+        OvsCleanupSttTunnel(vport);
         break;
     case OVS_VPORT_TYPE_GRE:
-    case OVS_VPORT_TYPE_GRE64:
+        OvsCleanupGreTunnel(vport);
         break;
     case OVS_VPORT_TYPE_NETDEV:
+        if (vport->isExternal) {
+            if (vport->nicIndex == 0) {
+                /* Such a vport is not part of any of the hash tables, since it
+                 * is not exposed to userspace. See Vport.h for explanation. */
+                ASSERT(hvDelete == TRUE);
+                ASSERT(switchContext->numPhysicalNics == 0);
+                switchContext->virtualExternalPortId = 0;
+                switchContext->virtualExternalVport = NULL;
+                OvsFreeMemoryWithTag(vport, OVS_VPORT_POOL_TAG);
+                return STATUS_SUCCESS;
+            }
+        }
         hvSwitchPort = TRUE;
     default:
         break;
     }
 
-    RemoveEntryList(&vport->ovsNameLink);
-    RemoveEntryList(&vport->portIdLink);
-    RemoveEntryList(&vport->portNoLink);
-    if (hvSwitchPort) {
-        switchContext->numHvVports--;
-    } else {
-        switchContext->numNonHvVports--;
+    /*
+     * 'hvDelete' == TRUE indicates that the port should be removed from the
+     * 'portIdHashArray', while 'ovsDelete' == TRUE indicates that the port
+     * should be removed from 'portNoHashArray' and the 'ovsPortNameHashArray'.
+     *
+     * Both 'hvDelete' and 'ovsDelete' can be set to TRUE by the caller.
+     */
+    if (vport->isAbsentOnHv == TRUE) {
+        deletedOnHv = TRUE;
+    }
+    if (vport->portNo == OVS_DPPORT_NUMBER_INVALID) {
+        deletedOnOvs = TRUE;
     }
-    OvsFreeMemory(vport);
-}
 
+    if (hvDelete && !deletedOnHv) {
+        vport->isAbsentOnHv = TRUE;
 
-NDIS_STATUS
-OvsAddConfiguredSwitchPorts(POVS_SWITCH_CONTEXT switchContext)
-{
-    NDIS_STATUS status = NDIS_STATUS_SUCCESS;
-    ULONG arrIndex;
-    PNDIS_SWITCH_PORT_PARAMETERS portParam;
-    PNDIS_SWITCH_PORT_ARRAY portArray = NULL;
-    POVS_VPORT_ENTRY vport;
+        if (vport->isExternal) {
+            ASSERT(vport->nicIndex != 0);
+            ASSERT(switchContext->numPhysicalNics);
+            switchContext->numPhysicalNics--;
+        }
 
-    OVS_LOG_TRACE("Enter: switchContext:%p", switchContext);
+        /* Remove the port from the relevant lists. */
+        RemoveEntryList(&vport->portIdLink);
+        InitializeListHead(&vport->portIdLink);
+        deletedOnHv = TRUE;
+    }
+    if (ovsDelete && !deletedOnOvs) {
+        vport->portNo = OVS_DPPORT_NUMBER_INVALID;
+        vport->ovsName[0] = '\0';
+
+        /* Remove the port from the relevant lists. */
+        RemoveEntryList(&vport->ovsNameLink);
+        InitializeListHead(&vport->ovsNameLink);
+        RemoveEntryList(&vport->portNoLink);
+        InitializeListHead(&vport->portNoLink);
+        if (OVS_VPORT_TYPE_VXLAN == vport->ovsType ||
+            OVS_VPORT_TYPE_STT == vport->ovsType   ||
+            OVS_VPORT_TYPE_GRE == vport->ovsType) {
+            RemoveEntryList(&vport->tunnelVportLink);
+            InitializeListHead(&vport->tunnelVportLink);
+        }
+
+        deletedOnOvs = TRUE;
+    }
+
+    /*
+     * Deallocate the port if it has been deleted on the Hyper-V switch as well
+     * as OVS userspace.
+     */
+    if (deletedOnHv && deletedOnOvs) {
+        if (hvSwitchPort) {
+            switchContext->numHvVports--;
+        } else {
+            switchContext->numNonHvVports--;
+        }
+        OvsFreeMemoryWithTag(vport, OVS_VPORT_POOL_TAG);
+    }
+
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS
+OvsRemoveTunnelVport(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                     POVS_SWITCH_CONTEXT switchContext,
+                     POVS_VPORT_ENTRY vport,
+                     BOOLEAN hvDelete,
+                     BOOLEAN ovsDelete)
+{
+    POVS_TUNFLT_INIT_CONTEXT tunnelContext = NULL;
+    PIRP irp = NULL;
+
+    tunnelContext = OvsAllocateMemoryWithTag(sizeof(*tunnelContext),
+                                             OVS_VPORT_POOL_TAG);
+    if (tunnelContext == NULL) {
+        return STATUS_INSUFFICIENT_RESOURCES;
+    }
+    RtlZeroMemory(tunnelContext, sizeof(*tunnelContext));
+
+    tunnelContext->switchContext = switchContext;
+    tunnelContext->hvSwitchPort = FALSE;
+    tunnelContext->hvDelete = hvDelete;
+    tunnelContext->ovsDelete = ovsDelete;
+    tunnelContext->vport = vport;
+
+    if (usrParamsCtx) {
+        tunnelContext->inputBuffer = usrParamsCtx->inputBuffer;
+        tunnelContext->outputBuffer = usrParamsCtx->outputBuffer;
+        tunnelContext->outputLength = usrParamsCtx->outputLength;
+        irp = usrParamsCtx->irp;
+    }
+
+    return OvsCleanupVxlanTunnel(irp, vport, OvsTunnelVportPendingRemove,
+                                 tunnelContext);
+}
+
+/*
+ * --------------------------------------------------------------------------
+ * Enumerates the ports on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
+NDIS_STATUS
+OvsAddConfiguredSwitchPorts(POVS_SWITCH_CONTEXT switchContext)
+{
+    NDIS_STATUS status = NDIS_STATUS_SUCCESS;
+    ULONG arrIndex;
+    PNDIS_SWITCH_PORT_PARAMETERS portParam;
+    PNDIS_SWITCH_PORT_ARRAY portArray = NULL;
+
+    OVS_LOG_TRACE("Enter: switchContext:%p", switchContext);
 
     status = OvsGetPortsOnSwitch(switchContext, &portArray);
     if (status != NDIS_STATUS_SUCCESS) {
@@ -1057,31 +1408,29 @@ OvsAddConfiguredSwitchPorts(POVS_SWITCH_CONTEXT switchContext)
              continue;
          }
 
-         vport = (POVS_VPORT_ENTRY)OvsAllocateVport();
-         if (vport == NULL) {
-             status = NDIS_STATUS_RESOURCES;
-             goto cleanup;
-         }
-         OvsInitVportWithPortParam(vport, portParam);
-         status = InitHvVportCommon(switchContext, vport);
-         if (status != NDIS_STATUS_SUCCESS) {
-             OvsFreeMemory(vport);
-             goto cleanup;
+         status = HvCreatePort(switchContext, portParam, 0);
+         if (status != STATUS_SUCCESS && status != STATUS_DATA_NOT_ACCEPTED) {
+             break;
          }
     }
+
 cleanup:
     if (status != NDIS_STATUS_SUCCESS) {
         OvsClearAllSwitchVports(switchContext);
     }
 
-    if (portArray != NULL) {
-        OvsFreeMemory(portArray);
-    }
+    OvsFreeSwitchPortsArray(portArray);
+
     OVS_LOG_TRACE("Exit: status: %x", status);
+
     return status;
 }
 
-
+/*
+ * --------------------------------------------------------------------------
+ * Enumerates the NICs on the Hyper-V switch.
+ * --------------------------------------------------------------------------
+ */
 NDIS_STATUS
 OvsInitConfiguredSwitchNics(POVS_SWITCH_CONTEXT switchContext)
 {
@@ -1089,7 +1438,6 @@ OvsInitConfiguredSwitchNics(POVS_SWITCH_CONTEXT switchContext)
     PNDIS_SWITCH_NIC_ARRAY nicArray = NULL;
     ULONG arrIndex;
     PNDIS_SWITCH_NIC_PARAMETERS nicParam;
-    POVS_VPORT_ENTRY vport;
 
     OVS_LOG_TRACE("Enter: switchContext: %p", switchContext);
     /*
@@ -1100,53 +1448,24 @@ OvsInitConfiguredSwitchNics(POVS_SWITCH_CONTEXT switchContext)
         goto cleanup;
     }
     for (arrIndex = 0; arrIndex < nicArray->NumElements; ++arrIndex) {
-
         nicParam = NDIS_SWITCH_NIC_AT_ARRAY_INDEX(nicArray, arrIndex);
 
         /*
          * XXX: Check if the port is configured with a VLAN. Disallow such a
          * configuration, since we don't support tag-in-tag.
-         */
-
-        /*
          * XXX: Check if the port is connected to a VF. Disconnect the VF in
          * such a case.
          */
 
-        if (nicParam->NicType == NdisSwitchNicTypeExternal &&
-            nicParam->NicIndex != 0) {
-            POVS_VPORT_ENTRY virtExtVport =
-                   (POVS_VPORT_ENTRY)switchContext->virtualExternalVport;
-
-            vport = OvsAllocateVport();
-            if (vport) {
-                OvsInitPhysNicVport(vport, virtExtVport,
-                                    nicParam->NicIndex);
-                status = InitHvVportCommon(switchContext, vport);
-                if (status != NDIS_STATUS_SUCCESS) {
-                    OvsFreeMemory(vport);
-                    vport = NULL;
-                }
-            }
-        } else {
-            vport = OvsFindVportByPortIdAndNicIndex(switchContext,
-                                                    nicParam->PortId,
-                                                    nicParam->NicIndex);
-        }
-        if (vport == NULL) {
-            OVS_LOG_ERROR("Fail to allocate vport");
-            continue;
-        }
-        OvsInitVportWithNicParam(switchContext, vport, nicParam);
-        if (nicParam->NicType == NdisSwitchNicTypeInternal) {
-            OvsInternalAdapterUp(vport->portNo, &nicParam->NetCfgInstanceId);
+        status = HvCreateNic(switchContext, nicParam);
+        if (status == NDIS_STATUS_SUCCESS) {
+            HvConnectNic(switchContext, nicParam);
         }
     }
 cleanup:
 
-    if (nicArray != NULL) {
-        OvsFreeMemory(nicArray);
-    }
+    OvsFreeSwitchNicsArray(nicArray);
+
     OVS_LOG_TRACE("Exit: status: %x", status);
     return status;
 }
@@ -1156,7 +1475,7 @@ cleanup:
  * Deletes ports added from the Hyper-V switch as well as OVS usersapce. The
  * function deletes ports in 'portIdHashArray'. This will delete most of the
  * ports that are in the 'portNoHashArray' as well. Any remaining ports
- * are deleted by walking the the 'portNoHashArray'.
+ * are deleted by walking the 'portNoHashArray'.
  * --------------------------------------------------------------------------
  */
 VOID
@@ -1169,35 +1488,35 @@ OvsClearAllSwitchVports(POVS_SWITCH_CONTEXT switchContext)
         LIST_FORALL_SAFE(head, link, next) {
             POVS_VPORT_ENTRY vport;
             vport = CONTAINING_RECORD(link, OVS_VPORT_ENTRY, portIdLink);
-            OvsRemoveAndDeleteVport(switchContext, vport);
+            OvsRemoveAndDeleteVport(NULL, switchContext, vport, TRUE, TRUE);
         }
     }
+
     /*
      * Remove 'virtualExternalVport' as well. This port is not part of the
      * 'portIdHashArray'.
      */
     if (switchContext->virtualExternalVport) {
-        OvsRemoveAndDeleteVport(switchContext,
-            (POVS_VPORT_ENTRY)switchContext->virtualExternalVport);
+        OvsRemoveAndDeleteVport(NULL, switchContext,
+            (POVS_VPORT_ENTRY)switchContext->virtualExternalVport, TRUE, TRUE);
     }
 
+
     for (UINT hash = 0; hash < OVS_MAX_VPORT_ARRAY_SIZE; hash++) {
         PLIST_ENTRY head, link, next;
-
         head = &(switchContext->portNoHashArray[hash & OVS_VPORT_MASK]);
         LIST_FORALL_SAFE(head, link, next) {
             POVS_VPORT_ENTRY vport;
             vport = CONTAINING_RECORD(link, OVS_VPORT_ENTRY, portNoLink);
             ASSERT(OvsIsTunnelVportType(vport->ovsType) ||
                    (vport->ovsType == OVS_VPORT_TYPE_INTERNAL &&
-                    vport->isBridgeInternal));
-            OvsRemoveAndDeleteVport(switchContext, vport);
+                    vport->isBridgeInternal) || vport->isAbsentOnHv == TRUE);
+            OvsRemoveAndDeleteVport(NULL, switchContext, vport, TRUE, TRUE);
         }
     }
 
     ASSERT(switchContext->virtualExternalVport == NULL);
     ASSERT(switchContext->internalVport == NULL);
-    ASSERT(switchContext->vxlanVport == NULL);
 }
 
 
@@ -1235,7 +1554,12 @@ OvsConvertIfCountedStrToAnsiStr(PIF_COUNTED_STRING wStr,
     return STATUS_SUCCESS;
 }
 
-
+/*
+ * --------------------------------------------------------------------------
+ * Utility function that populates a 'OVS_VPORT_EXT_INFO' structure for the
+ * specified vport.
+ * --------------------------------------------------------------------------
+ */
 NTSTATUS
 OvsGetExtInfoIoctl(POVS_VPORT_GET vportGet,
                    POVS_VPORT_EXT_INFO extInfo)
@@ -1247,11 +1571,15 @@ OvsGetExtInfoIoctl(POVS_VPORT_GET vportGet,
     BOOLEAN doConvert = FALSE;
 
     RtlZeroMemory(extInfo, sizeof (POVS_VPORT_EXT_INFO));
-    NdisAcquireRWLockRead(gOvsSwitchContext->dispatchLock, &lockState,
-                          NDIS_RWL_AT_DISPATCH_LEVEL);
+    NdisAcquireRWLockRead(gOvsSwitchContext->dispatchLock, &lockState, 0);
     if (vportGet->portNo == 0) {
         StringCbLengthA(vportGet->name, OVS_MAX_PORT_NAME_LENGTH - 1, &len);
-        vport = OvsFindVportByHvName(gOvsSwitchContext, vportGet->name);
+        vport = OvsFindVportByHvNameA(gOvsSwitchContext, vportGet->name);
+        if (vport == NULL) {
+            /* If the port is not a Hyper-V port and it has been added earlier,
+             * we'll find it in 'ovsPortNameHashArray'. */
+            vport = OvsFindVportByOvsName(gOvsSwitchContext, vportGet->name);
+        }
     } else {
         vport = OvsFindVportByPortNo(gOvsSwitchContext, vportGet->portNo);
     }
@@ -1299,7 +1627,6 @@ OvsGetExtInfoIoctl(POVS_VPORT_GET vportGet,
         extInfo->vifUUID[0] = 0;
     }
     NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
-    NdisReleaseSpinLock(gOvsCtrlLock);
     if (doConvert) {
         status = OvsConvertIfCountedStrToAnsiStr(&vport->portFriendlyName,
                                                  extInfo->name,
@@ -1368,13 +1695,8 @@ OvsGetNetdevCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
     if (!NlAttrParse((PNL_MSG_HDR)msgIn,
         NLMSG_HDRLEN + GENL_HDRLEN + OVS_HDRLEN,
         NlMsgAttrsLen((PNL_MSG_HDR)msgIn),
-        ovsNetdevPolicy, netdevAttrs, ARRAY_SIZE(netdevAttrs))) {
-        return STATUS_INVALID_PARAMETER;
-    }
-
-    OvsAcquireCtrlLock();
-    if (!gOvsSwitchContext) {
-        OvsReleaseCtrlLock();
+        ovsNetdevPolicy, ARRAY_SIZE(ovsNetdevPolicy),
+        netdevAttrs, ARRAY_SIZE(netdevAttrs))) {
         return STATUS_INVALID_PARAMETER;
     }
 
@@ -1385,7 +1707,6 @@ OvsGetNetdevCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
     status = OvsGetExtInfoIoctl(&vportGet, &info);
     if (status == STATUS_DEVICE_DOES_NOT_EXIST) {
         nlError = NL_ERROR_NODEV;
-        OvsReleaseCtrlLock();
         goto cleanup;
     }
 
@@ -1395,14 +1716,13 @@ OvsGetNetdevCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
     if (status == STATUS_SUCCESS) {
         *replyLen = msgOut->nlMsg.nlmsgLen;
     }
-    OvsReleaseCtrlLock();
 
 cleanup:
     if (nlError != NL_ERROR_SUCCESS) {
         POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR)
             usrParamsCtx->outputBuffer;
 
-        BuildErrorMsg(msgIn, msgError, nlError);
+        NlBuildErrorMsg(msgIn, msgError, nlError);
         *replyLen = msgError->nlMsg.nlmsgLen;
     }
 
@@ -1425,46 +1745,45 @@ CreateNetlinkMesgForNetdev(POVS_VPORT_EXT_INFO info,
 {
     NL_BUFFER nlBuffer;
     BOOLEAN ok;
-    OVS_MESSAGE msgOut;
     PNL_MSG_HDR nlMsg;
     UINT32 netdevFlags = 0;
 
     NlBufInit(&nlBuffer, outBuffer, outBufLen);
 
-    BuildReplyMsgFromMsgIn(msgIn, &msgOut, 0);
-    msgOut.ovsHdr.dp_ifindex = dpIfIndex;
-
-    ok = NlMsgPutHead(&nlBuffer, (PCHAR)&msgOut, sizeof msgOut);
+    ok = NlFillOvsMsg(&nlBuffer, msgIn->nlMsg.nlmsgType, NLM_F_MULTI,
+                      msgIn->nlMsg.nlmsgSeq, msgIn->nlMsg.nlmsgPid,
+                      msgIn->genlMsg.cmd, msgIn->genlMsg.version,
+                      dpIfIndex);
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     ok = NlMsgPutTailU32(&nlBuffer, OVS_WIN_NETDEV_ATTR_PORT_NO,
                          info->portNo);
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     ok = NlMsgPutTailU32(&nlBuffer, OVS_WIN_NETDEV_ATTR_TYPE, info->type);
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     ok = NlMsgPutTailString(&nlBuffer, OVS_WIN_NETDEV_ATTR_NAME,
                             info->name);
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     ok = NlMsgPutTailUnspec(&nlBuffer, OVS_WIN_NETDEV_ATTR_MAC_ADDR,
              (PCHAR)info->macAddress, sizeof (info->macAddress));
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     ok = NlMsgPutTailU32(&nlBuffer, OVS_WIN_NETDEV_ATTR_MTU, info->mtu);
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     if (info->status != OVS_EVENT_CONNECT) {
@@ -1473,7 +1792,7 @@ CreateNetlinkMesgForNetdev(POVS_VPORT_EXT_INFO info,
     ok = NlMsgPutTailU32(&nlBuffer, OVS_WIN_NETDEV_ATTR_IF_FLAGS,
                          netdevFlags);
     if (!ok) {
-        return STATUS_INSUFFICIENT_RESOURCES;
+        return STATUS_INVALID_BUFFER_SIZE;
     }
 
     /*
@@ -1497,3 +1816,909 @@ OvsWaitActivate(POVS_SWITCH_CONTEXT switchContext, ULONG sleepMicroSec)
         NdisMSleep(sleepMicroSec);
     }
 }
+
+static NTSTATUS
+OvsCreateMsgFromVport(POVS_VPORT_ENTRY vport,
+                      POVS_MESSAGE msgIn,
+                      PVOID outBuffer,
+                      UINT32 outBufLen,
+                      int dpIfIndex)
+{
+    NL_BUFFER nlBuffer;
+    OVS_VPORT_FULL_STATS vportStats;
+    BOOLEAN ok;
+    PNL_MSG_HDR nlMsg;
+
+    NlBufInit(&nlBuffer, outBuffer, outBufLen);
+
+    ok = NlFillOvsMsg(&nlBuffer, msgIn->nlMsg.nlmsgType, NLM_F_MULTI,
+                      msgIn->nlMsg.nlmsgSeq, msgIn->nlMsg.nlmsgPid,
+                      msgIn->genlMsg.cmd, msgIn->genlMsg.version,
+                      dpIfIndex);
+    if (!ok) {
+        return STATUS_INVALID_BUFFER_SIZE;
+    }
+
+    ok = NlMsgPutTailU32(&nlBuffer, OVS_VPORT_ATTR_PORT_NO, vport->portNo);
+    if (!ok) {
+        return STATUS_INVALID_BUFFER_SIZE;
+    }
+
+    ok = NlMsgPutTailU32(&nlBuffer, OVS_VPORT_ATTR_TYPE, vport->ovsType);
+    if (!ok) {
+        return STATUS_INVALID_BUFFER_SIZE;
+    }
+
+    ok = NlMsgPutTailString(&nlBuffer, OVS_VPORT_ATTR_NAME, vport->ovsName);
+    if (!ok) {
+        return STATUS_INVALID_BUFFER_SIZE;
+    }
+
+    /*
+     * XXX: when we implement OVS_DP_ATTR_USER_FEATURES in datapath,
+     * we'll need to check the OVS_DP_F_VPORT_PIDS flag: if it is set,
+     * it means we have an array of pids, instead of a single pid.
+     * ATM we assume we have one pid only.
+    */
+
+    ok = NlMsgPutTailU32(&nlBuffer, OVS_VPORT_ATTR_UPCALL_PID,
+                         vport->upcallPid);
+    if (!ok) {
+        return STATUS_INVALID_BUFFER_SIZE;
+    }
+
+    /*stats*/
+    vportStats.rxPackets = vport->stats.rxPackets;
+    vportStats.rxBytes = vport->stats.rxBytes;
+    vportStats.txPackets = vport->stats.txPackets;
+    vportStats.txBytes = vport->stats.txBytes;
+    vportStats.rxErrors = vport->errStats.rxErrors;
+    vportStats.txErrors = vport->errStats.txErrors;
+    vportStats.rxDropped = vport->errStats.rxDropped;
+    vportStats.txDropped = vport->errStats.txDropped;
+
+    ok = NlMsgPutTailUnspec(&nlBuffer, OVS_VPORT_ATTR_STATS,
+                            (PCHAR)&vportStats,
+                            sizeof(OVS_VPORT_FULL_STATS));
+    if (!ok) {
+        return STATUS_INVALID_BUFFER_SIZE;
+    }
+
+    /*
+     * XXX: when vxlan udp dest port becomes configurable, we will also need
+     * to add vport options
+    */
+
+    nlMsg = (PNL_MSG_HDR)NlBufAt(&nlBuffer, 0, 0);
+    nlMsg->nlmsgLen = NlBufSize(&nlBuffer);
+
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS
+OvsGetVportDumpNext(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                    UINT32 *replyLen)
+{
+    POVS_MESSAGE msgIn;
+    POVS_OPEN_INSTANCE instance =
+        (POVS_OPEN_INSTANCE)usrParamsCtx->ovsInstance;
+    LOCK_STATE_EX lockState;
+    UINT32 i = OVS_MAX_VPORT_ARRAY_SIZE;
+
+    /*
+     * XXX: this function shares some code with other dump command(s).
+     * In the future, we will need to refactor the dump functions
+    */
+
+    ASSERT(usrParamsCtx->devOp == OVS_READ_DEV_OP);
+
+    if (instance->dumpState.ovsMsg == NULL) {
+        ASSERT(FALSE);
+        return STATUS_INVALID_DEVICE_STATE;
+    }
+
+    /* Output buffer has been validated while validating read dev op. */
+    ASSERT(usrParamsCtx->outputBuffer != NULL);
+
+    msgIn = instance->dumpState.ovsMsg;
+
+    /*
+     * XXX: when we implement OVS_DP_ATTR_USER_FEATURES in datapath,
+     * we'll need to check the OVS_DP_F_VPORT_PIDS flag: if it is set,
+     * it means we have an array of pids, instead of a single pid.
+     * ATM we assume we have one pid only.
+    */
+    NdisAcquireRWLockRead(gOvsSwitchContext->dispatchLock, &lockState, 0);
+
+    if (gOvsSwitchContext->numHvVports > 0 ||
+            gOvsSwitchContext->numNonHvVports > 0) {
+        /* inBucket: the bucket, used for lookup */
+        UINT32 inBucket = instance->dumpState.index[0];
+        /* inIndex: index within the given bucket, used for lookup */
+        UINT32 inIndex = instance->dumpState.index[1];
+        /* the bucket to be used for the next dump operation */
+        UINT32 outBucket = 0;
+        /* the index within the outBucket to be used for the next dump */
+        UINT32 outIndex = 0;
+
+        for (i = inBucket; i < OVS_MAX_VPORT_ARRAY_SIZE; i++) {
+            PLIST_ENTRY head, link;
+            head = &(gOvsSwitchContext->portNoHashArray[i]);
+            POVS_VPORT_ENTRY vport = NULL;
+
+            outIndex = 0;
+            LIST_FORALL(head, link) {
+
+                /*
+                 * if one or more dumps were previously done on this same bucket,
+                 * inIndex will be > 0, so we'll need to reply with the
+                 * inIndex + 1 vport from the bucket.
+                */
+                if (outIndex >= inIndex) {
+                    vport = CONTAINING_RECORD(link, OVS_VPORT_ENTRY, portNoLink);
+
+                    ASSERT(vport->portNo != OVS_DPPORT_NUMBER_INVALID);
+                    OvsCreateMsgFromVport(vport, msgIn,
+                                          usrParamsCtx->outputBuffer,
+                                          usrParamsCtx->outputLength,
+                                          gOvsSwitchContext->dpNo);
+                    ++outIndex;
+                    break;
+                }
+
+                ++outIndex;
+            }
+
+            if (vport) {
+                break;
+            }
+
+            /*
+             * if no vport was found above, check the next bucket, beginning
+             * with the first (i.e. index 0) elem from within that bucket
+            */
+            inIndex = 0;
+        }
+
+        outBucket = i;
+
+        /* XXX: what about NLMSG_DONE (as msg type)? */
+        instance->dumpState.index[0] = outBucket;
+        instance->dumpState.index[1] = outIndex;
+    }
+
+    NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+
+    /* if i < OVS_MAX_VPORT_ARRAY_SIZE => vport was found */
+    if (i < OVS_MAX_VPORT_ARRAY_SIZE) {
+        POVS_MESSAGE msgOut = (POVS_MESSAGE)usrParamsCtx->outputBuffer;
+        *replyLen = msgOut->nlMsg.nlmsgLen;
+    } else {
+        /*
+         * if i >= OVS_MAX_VPORT_ARRAY_SIZE => vport was not found =>
+         * it's dump done
+         */
+        *replyLen = 0;
+        /* Free up the dump state, since there's no more data to continue. */
+        FreeUserDumpState(instance);
+    }
+
+    return STATUS_SUCCESS;
+}
+
+static NTSTATUS
+OvsGetVport(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+            UINT32 *replyLen)
+{
+    NTSTATUS status = STATUS_SUCCESS;
+    LOCK_STATE_EX lockState;
+
+    POVS_MESSAGE msgIn = (POVS_MESSAGE)usrParamsCtx->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)usrParamsCtx->outputBuffer;
+    POVS_VPORT_ENTRY vport = NULL;
+    NL_ERROR nlError = NL_ERROR_SUCCESS;
+    PCHAR portName = NULL;
+    UINT32 portNameLen = 0;
+    UINT32 portNumber = OVS_DPPORT_NUMBER_INVALID;
+
+    static const NL_POLICY ovsVportPolicy[] = {
+        [OVS_VPORT_ATTR_PORT_NO] = { .type = NL_A_U32, .optional = TRUE },
+        [OVS_VPORT_ATTR_NAME] = { .type = NL_A_STRING,
+                                  .minLen = 2,
+                                  .maxLen = IFNAMSIZ,
+                                  .optional = TRUE},
+    };
+    PNL_ATTR vportAttrs[ARRAY_SIZE(ovsVportPolicy)];
+
+    /* input buffer has been validated while validating write dev op. */
+    ASSERT(usrParamsCtx->inputBuffer != NULL);
+
+    if (!NlAttrParse((PNL_MSG_HDR)msgIn,
+        NLMSG_HDRLEN + GENL_HDRLEN + OVS_HDRLEN,
+        NlMsgAttrsLen((PNL_MSG_HDR)msgIn),
+        ovsVportPolicy, ARRAY_SIZE(ovsVportPolicy),
+        vportAttrs, ARRAY_SIZE(vportAttrs))) {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Output buffer has been validated while validating transact dev op. */
+    ASSERT(msgOut != NULL && usrParamsCtx->outputLength >= sizeof *msgOut);
+
+    NdisAcquireRWLockRead(gOvsSwitchContext->dispatchLock, &lockState, 0);
+    if (vportAttrs[OVS_VPORT_ATTR_NAME] != NULL) {
+        portName = NlAttrGet(vportAttrs[OVS_VPORT_ATTR_NAME]);
+        portNameLen = NlAttrGetSize(vportAttrs[OVS_VPORT_ATTR_NAME]);
+
+        /* the port name is expected to be null-terminated */
+        ASSERT(portName[portNameLen - 1] == '\0');
+
+        vport = OvsFindVportByOvsName(gOvsSwitchContext, portName);
+    } else if (vportAttrs[OVS_VPORT_ATTR_PORT_NO] != NULL) {
+        portNumber = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_PORT_NO]);
+
+        vport = OvsFindVportByPortNo(gOvsSwitchContext, portNumber);
+    } else {
+        nlError = NL_ERROR_INVAL;
+        NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+        goto Cleanup;
+    }
+
+    if (!vport) {
+        nlError = NL_ERROR_NODEV;
+        NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+        goto Cleanup;
+    }
+
+    status = OvsCreateMsgFromVport(vport, msgIn, usrParamsCtx->outputBuffer,
+                                   usrParamsCtx->outputLength,
+                                   gOvsSwitchContext->dpNo);
+    NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+
+    *replyLen = msgOut->nlMsg.nlmsgLen;
+
+Cleanup:
+    if (nlError != NL_ERROR_SUCCESS) {
+        POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR)
+            usrParamsCtx->outputBuffer;
+
+        NlBuildErrorMsg(msgIn, msgError, nlError);
+        *replyLen = msgError->nlMsg.nlmsgLen;
+    }
+
+    return STATUS_SUCCESS;
+}
+
+/*
+ * --------------------------------------------------------------------------
+ *  Command Handler for 'OVS_VPORT_CMD_GET'.
+ *
+ *  The function handles the initial call to setup the dump state, as well as
+ *  subsequent calls to continue dumping data.
+ * --------------------------------------------------------------------------
+*/
+NTSTATUS
+OvsGetVportCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                      UINT32 *replyLen)
+{
+    *replyLen = 0;
+
+    switch (usrParamsCtx->devOp) {
+    case OVS_WRITE_DEV_OP:
+        return OvsSetupDumpStart(usrParamsCtx);
+
+    case OVS_READ_DEV_OP:
+        return OvsGetVportDumpNext(usrParamsCtx, replyLen);
+
+    case OVS_TRANSACTION_DEV_OP:
+        return OvsGetVport(usrParamsCtx, replyLen);
+
+    default:
+        return STATUS_INVALID_DEVICE_REQUEST;
+    }
+
+}
+
+static UINT32
+OvsComputeVportNo(POVS_SWITCH_CONTEXT switchContext)
+{
+    /* we are not allowed to create the port OVS_DPPORT_NUMBER_LOCAL */
+    for (ULONG i = OVS_DPPORT_NUMBER_LOCAL + 1; i < MAXUINT16; ++i) {
+        POVS_VPORT_ENTRY vport;
+
+        vport = OvsFindVportByPortNo(switchContext, i);
+        if (!vport) {
+            return i;
+        }
+    }
+
+    return OVS_DPPORT_NUMBER_INVALID;
+}
+
+/*
+ * --------------------------------------------------------------------------
+ *  Command Handler for 'OVS_VPORT_CMD_NEW'.
+ * --------------------------------------------------------------------------
+ */
+NTSTATUS
+OvsNewVportCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                      UINT32 *replyLen)
+{
+    NDIS_STATUS status = STATUS_SUCCESS;
+    LOCK_STATE_EX lockState;
+
+    NL_ERROR nlError = NL_ERROR_SUCCESS;
+    POVS_MESSAGE msgIn = (POVS_MESSAGE)usrParamsCtx->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)usrParamsCtx->outputBuffer;
+    POVS_VPORT_ENTRY vport = NULL;
+    PCHAR portName;
+    ULONG portNameLen;
+    UINT32 portType;
+    BOOLEAN vportAllocated = FALSE, vportInitialized = FALSE;
+
+    static const NL_POLICY ovsVportPolicy[] = {
+        [OVS_VPORT_ATTR_PORT_NO] = { .type = NL_A_U32, .optional = TRUE },
+        [OVS_VPORT_ATTR_TYPE] = { .type = NL_A_U32, .optional = FALSE },
+        [OVS_VPORT_ATTR_NAME] = { .type = NL_A_STRING, .maxLen = IFNAMSIZ,
+                                  .optional = FALSE},
+        [OVS_VPORT_ATTR_UPCALL_PID] = { .type = NL_A_UNSPEC,
+                                        .optional = FALSE },
+        [OVS_VPORT_ATTR_OPTIONS] = { .type = NL_A_NESTED, .optional = TRUE },
+    };
+
+    PNL_ATTR vportAttrs[ARRAY_SIZE(ovsVportPolicy)];
+
+    /* input buffer has been validated while validating write dev op. */
+    ASSERT(usrParamsCtx->inputBuffer != NULL);
+
+    /* Output buffer has been validated while validating transact dev op. */
+    ASSERT(msgOut != NULL && usrParamsCtx->outputLength >= sizeof *msgOut);
+
+    if (!NlAttrParse((PNL_MSG_HDR)msgIn,
+        NLMSG_HDRLEN + GENL_HDRLEN + OVS_HDRLEN,
+        NlMsgAttrsLen((PNL_MSG_HDR)msgIn),
+        ovsVportPolicy, ARRAY_SIZE(ovsVportPolicy),
+        vportAttrs, ARRAY_SIZE(vportAttrs))) {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    portName = NlAttrGet(vportAttrs[OVS_VPORT_ATTR_NAME]);
+    portNameLen = NlAttrGetSize(vportAttrs[OVS_VPORT_ATTR_NAME]);
+    portType = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_TYPE]);
+
+    /* we are expecting null terminated strings to be passed */
+    ASSERT(portName[portNameLen - 1] == '\0');
+
+    NdisAcquireRWLockWrite(gOvsSwitchContext->dispatchLock, &lockState, 0);
+
+    vport = OvsFindVportByOvsName(gOvsSwitchContext, portName);
+    if (vport) {
+        nlError = NL_ERROR_EXIST;
+        goto Cleanup;
+    }
+
+    if (portType == OVS_VPORT_TYPE_NETDEV) {
+        /* External ports can also be looked up like VIF ports. */
+        vport = OvsFindVportByHvNameA(gOvsSwitchContext, portName);
+    } else {
+        ASSERT(OvsIsTunnelVportType(portType) ||
+               portType == OVS_VPORT_TYPE_INTERNAL);
+
+        vport = (POVS_VPORT_ENTRY)OvsAllocateVport();
+        if (vport == NULL) {
+            nlError = NL_ERROR_NOMEM;
+            goto Cleanup;
+        }
+        vportAllocated = TRUE;
+
+        if (OvsIsTunnelVportType(portType)) {
+            UINT16 transportPortDest = 0;
+
+            switch (portType) {
+            case OVS_VPORT_TYPE_GRE:
+                break;
+            case OVS_VPORT_TYPE_VXLAN:
+                transportPortDest = VXLAN_UDP_PORT;
+                break;
+            case OVS_VPORT_TYPE_STT:
+                transportPortDest = STT_TCP_PORT;
+                break;
+            default:
+                nlError = NL_ERROR_INVAL;
+                goto Cleanup;
+            }
+
+            if (vportAttrs[OVS_VPORT_ATTR_OPTIONS]) {
+                PNL_ATTR attr = NlAttrFindNested(vportAttrs[OVS_VPORT_ATTR_OPTIONS],
+                                                 OVS_TUNNEL_ATTR_DST_PORT);
+                if (attr) {
+                    transportPortDest = NlAttrGetU16(attr);
+                }
+            }
+
+            status = OvsInitTunnelVport(usrParamsCtx,
+                                        vport,
+                                        portType,
+                                        transportPortDest);
+
+            nlError = NlMapStatusToNlErr(status);
+        } else {
+            OvsInitBridgeInternalVport(vport);
+        }
+
+        vportInitialized = TRUE;
+
+        if (nlError == NL_ERROR_SUCCESS) {
+            vport->ovsState = OVS_STATE_CONNECTED;
+            vport->nicState = NdisSwitchNicStateConnected;
+
+            /*
+             * Allow the vport to be deleted, because there is no
+             * corresponding hyper-v switch part.
+             */
+            vport->isAbsentOnHv = TRUE;
+        } else {
+            goto Cleanup;
+        }
+    }
+
+    if (!vport) {
+        nlError = NL_ERROR_INVAL;
+        goto Cleanup;
+    }
+    if (vport->portNo != OVS_DPPORT_NUMBER_INVALID) {
+        nlError = NL_ERROR_EXIST;
+        goto Cleanup;
+    }
+
+    if (vportAttrs[OVS_VPORT_ATTR_PORT_NO] != NULL) {
+        /*
+         * XXX: when we implement the limit for ovs port number to be
+         * MAXUINT16, we'll need to check the port number received from the
+         * userspace.
+         */
+        vport->portNo = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_PORT_NO]);
+    } else {
+        vport->portNo = OvsComputeVportNo(gOvsSwitchContext);
+        if (vport->portNo == OVS_DPPORT_NUMBER_INVALID) {
+            nlError = NL_ERROR_NOMEM;
+            goto Cleanup;
+        }
+    }
+
+    /* The ovs port name must be uninitialized. */
+    ASSERT(vport->ovsName[0] == '\0');
+    ASSERT(portNameLen <= OVS_MAX_PORT_NAME_LENGTH);
+
+    RtlCopyMemory(vport->ovsName, portName, portNameLen);
+    /* if we don't have options, then vport->portOptions will be NULL */
+    vport->portOptions = vportAttrs[OVS_VPORT_ATTR_OPTIONS];
+
+    /*
+     * XXX: when we implement OVS_DP_ATTR_USER_FEATURES in datapath,
+     * we'll need to check the OVS_DP_F_VPORT_PIDS flag: if it is set,
+     * it means we have an array of pids, instead of a single pid.
+     * ATM we assume we have one pid only.
+     */
+    vport->upcallPid = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_UPCALL_PID]);
+
+    status = InitOvsVportCommon(gOvsSwitchContext, vport);
+    ASSERT(status == STATUS_SUCCESS);
+
+    status = OvsCreateMsgFromVport(vport, msgIn, usrParamsCtx->outputBuffer,
+                                   usrParamsCtx->outputLength,
+                                   gOvsSwitchContext->dpNo);
+
+    *replyLen = msgOut->nlMsg.nlmsgLen;
+
+Cleanup:
+    NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+
+    if ((nlError != NL_ERROR_SUCCESS) && (nlError != NL_ERROR_PENDING)) {
+        POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR)
+            usrParamsCtx->outputBuffer;
+
+        if (vport && vportAllocated == TRUE) {
+            if (vportInitialized == TRUE) {
+                if (OvsIsTunnelVportType(portType)) {
+                    switch (vport->ovsType) {
+                    case OVS_VPORT_TYPE_VXLAN:
+                        OvsCleanupVxlanTunnel(NULL, vport, NULL, NULL);
+                        break;
+                    case OVS_VPORT_TYPE_STT:
+                        OvsCleanupSttTunnel(vport);
+                        break;
+                    default:
+                        ASSERT(!"Invalid tunnel port type");
+                    }
+                }
+            }
+            OvsFreeMemoryWithTag(vport, OVS_VPORT_POOL_TAG);
+        }
+
+        NlBuildErrorMsg(msgIn, msgError, nlError);
+        *replyLen = msgError->nlMsg.nlmsgLen;
+    }
+
+    return (status == STATUS_PENDING) ? STATUS_PENDING : STATUS_SUCCESS;
+}
+
+
+/*
+ * --------------------------------------------------------------------------
+ *  Command Handler for 'OVS_VPORT_CMD_SET'.
+ * --------------------------------------------------------------------------
+ */
+NTSTATUS
+OvsSetVportCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                      UINT32 *replyLen)
+{
+    NDIS_STATUS status = STATUS_SUCCESS;
+    LOCK_STATE_EX lockState;
+
+    POVS_MESSAGE msgIn = (POVS_MESSAGE)usrParamsCtx->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)usrParamsCtx->outputBuffer;
+    POVS_VPORT_ENTRY vport = NULL;
+    NL_ERROR nlError = NL_ERROR_SUCCESS;
+
+    static const NL_POLICY ovsVportPolicy[] = {
+        [OVS_VPORT_ATTR_PORT_NO] = { .type = NL_A_U32, .optional = TRUE },
+        [OVS_VPORT_ATTR_TYPE] = { .type = NL_A_U32, .optional = TRUE },
+        [OVS_VPORT_ATTR_NAME] = { .type = NL_A_STRING, .maxLen = IFNAMSIZ,
+                                  .optional = TRUE },
+        [OVS_VPORT_ATTR_UPCALL_PID] = { .type = NL_A_UNSPEC,
+                                        .optional = TRUE },
+        [OVS_VPORT_ATTR_STATS] = { .type = NL_A_UNSPEC,
+                                   .minLen = sizeof(OVS_VPORT_FULL_STATS),
+                                   .maxLen = sizeof(OVS_VPORT_FULL_STATS),
+                                   .optional = TRUE },
+        [OVS_VPORT_ATTR_OPTIONS] = { .type = NL_A_NESTED, .optional = TRUE },
+    };
+    PNL_ATTR vportAttrs[ARRAY_SIZE(ovsVportPolicy)];
+
+    ASSERT(usrParamsCtx->inputBuffer != NULL);
+
+    if (!NlAttrParse((PNL_MSG_HDR)msgIn,
+        NLMSG_HDRLEN + GENL_HDRLEN + OVS_HDRLEN,
+        NlMsgAttrsLen((PNL_MSG_HDR)msgIn),
+        ovsVportPolicy, ARRAY_SIZE(ovsVportPolicy),
+        vportAttrs, ARRAY_SIZE(vportAttrs))) {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Output buffer has been validated while validating transact dev op. */
+    ASSERT(msgOut != NULL && usrParamsCtx->outputLength >= sizeof *msgOut);
+
+    NdisAcquireRWLockWrite(gOvsSwitchContext->dispatchLock, &lockState, 0);
+    if (vportAttrs[OVS_VPORT_ATTR_NAME] != NULL) {
+        PSTR portName = NlAttrGet(vportAttrs[OVS_VPORT_ATTR_NAME]);
+#ifdef DBG
+        UINT32 portNameLen = NlAttrGetSize(vportAttrs[OVS_VPORT_ATTR_NAME]);
+#endif
+        /* the port name is expected to be null-terminated */
+        ASSERT(portName[portNameLen - 1] == '\0');
+
+        vport = OvsFindVportByOvsName(gOvsSwitchContext, portName);
+    } else if (vportAttrs[OVS_VPORT_ATTR_PORT_NO] != NULL) {
+        vport = OvsFindVportByPortNo(gOvsSwitchContext,
+                    NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_PORT_NO]));
+    }
+
+    if (!vport) {
+        nlError = NL_ERROR_NODEV;
+        goto Cleanup;
+    }
+
+    /*
+     * XXX: when we implement OVS_DP_ATTR_USER_FEATURES in datapath,
+     * we'll need to check the OVS_DP_F_VPORT_PIDS flag: if it is set,
+     * it means we have an array of pids, instead of a single pid.
+     * Currently, we support only one pid.
+     */
+    if (vportAttrs[OVS_VPORT_ATTR_UPCALL_PID]) {
+        vport->upcallPid = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_UPCALL_PID]);
+    }
+
+    if (vportAttrs[OVS_VPORT_ATTR_TYPE]) {
+        OVS_VPORT_TYPE type = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_TYPE]);
+        if (type != vport->ovsType) {
+            nlError = NL_ERROR_INVAL;
+            goto Cleanup;
+        }
+    }
+
+    if (vportAttrs[OVS_VPORT_ATTR_OPTIONS]) {
+        OVS_LOG_ERROR("Vport options not supported");
+        nlError = NL_ERROR_NOTSUPP;
+        goto Cleanup;
+    }
+
+    status = OvsCreateMsgFromVport(vport, msgIn, usrParamsCtx->outputBuffer,
+                                   usrParamsCtx->outputLength,
+                                   gOvsSwitchContext->dpNo);
+
+    *replyLen = msgOut->nlMsg.nlmsgLen;
+
+Cleanup:
+    NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+
+    if (nlError != NL_ERROR_SUCCESS) {
+        POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR)
+            usrParamsCtx->outputBuffer;
+
+        NlBuildErrorMsg(msgIn, msgError, nlError);
+        *replyLen = msgError->nlMsg.nlmsgLen;
+    }
+
+    return STATUS_SUCCESS;
+}
+
+/*
+ * --------------------------------------------------------------------------
+ *  Command Handler for 'OVS_VPORT_CMD_DEL'.
+ * --------------------------------------------------------------------------
+ */
+NTSTATUS
+OvsDeleteVportCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
+                         UINT32 *replyLen)
+{
+    NDIS_STATUS status = STATUS_SUCCESS;
+    LOCK_STATE_EX lockState;
+
+    POVS_MESSAGE msgIn = (POVS_MESSAGE)usrParamsCtx->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)usrParamsCtx->outputBuffer;
+    POVS_VPORT_ENTRY vport = NULL;
+    NL_ERROR nlError = NL_ERROR_SUCCESS;
+    PSTR portName = NULL;
+    UINT32 portNameLen = 0;
+
+    static const NL_POLICY ovsVportPolicy[] = {
+        [OVS_VPORT_ATTR_PORT_NO] = { .type = NL_A_U32, .optional = TRUE },
+        [OVS_VPORT_ATTR_NAME] = { .type = NL_A_STRING, .maxLen = IFNAMSIZ,
+                                  .optional = TRUE },
+    };
+    PNL_ATTR vportAttrs[ARRAY_SIZE(ovsVportPolicy)];
+
+    ASSERT(usrParamsCtx->inputBuffer != NULL);
+
+    if (!NlAttrParse((PNL_MSG_HDR)msgIn,
+        NLMSG_HDRLEN + GENL_HDRLEN + OVS_HDRLEN,
+        NlMsgAttrsLen((PNL_MSG_HDR)msgIn),
+        ovsVportPolicy, ARRAY_SIZE(ovsVportPolicy),
+        vportAttrs, ARRAY_SIZE(vportAttrs))) {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Output buffer has been validated while validating transact dev op. */
+    ASSERT(msgOut != NULL && usrParamsCtx->outputLength >= sizeof *msgOut);
+
+    NdisAcquireRWLockWrite(gOvsSwitchContext->dispatchLock, &lockState, 0);
+    if (vportAttrs[OVS_VPORT_ATTR_NAME] != NULL) {
+        portName = NlAttrGet(vportAttrs[OVS_VPORT_ATTR_NAME]);
+        portNameLen = NlAttrGetSize(vportAttrs[OVS_VPORT_ATTR_NAME]);
+
+        /* the port name is expected to be null-terminated */
+        ASSERT(portName[portNameLen - 1] == '\0');
+
+        vport = OvsFindVportByOvsName(gOvsSwitchContext, portName);
+    }
+    else if (vportAttrs[OVS_VPORT_ATTR_PORT_NO] != NULL) {
+        vport = OvsFindVportByPortNo(gOvsSwitchContext,
+            NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_PORT_NO]));
+    }
+
+    if (!vport) {
+        nlError = NL_ERROR_NODEV;
+        goto Cleanup;
+    }
+
+    status = OvsCreateMsgFromVport(vport, msgIn, usrParamsCtx->outputBuffer,
+                                   usrParamsCtx->outputLength,
+                                   gOvsSwitchContext->dpNo);
+
+    *replyLen = msgOut->nlMsg.nlmsgLen;
+
+    /*
+     * Mark the port as deleted from OVS userspace. If the port does not exist
+     * on the Hyper-V switch, it gets deallocated. Otherwise, it stays.
+     */
+    status = OvsRemoveAndDeleteVport(usrParamsCtx,
+                                     gOvsSwitchContext,
+                                     vport,
+                                     FALSE,
+                                     TRUE);
+    if (status) {
+        nlError = NlMapStatusToNlErr(status);
+    }
+
+Cleanup:
+    NdisReleaseRWLock(gOvsSwitchContext->dispatchLock, &lockState);
+
+    if ((nlError != NL_ERROR_SUCCESS) && (nlError != NL_ERROR_PENDING)) {
+        POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR)
+            usrParamsCtx->outputBuffer;
+
+        NlBuildErrorMsg(msgIn, msgError, nlError);
+        *replyLen = msgError->nlMsg.nlmsgLen;
+    }
+
+    return (status == STATUS_PENDING) ? STATUS_PENDING : STATUS_SUCCESS;
+}
+
+static VOID
+OvsTunnelVportPendingRemove(PVOID context,
+                            NTSTATUS status,
+                            UINT32 *replyLen)
+{
+    POVS_TUNFLT_INIT_CONTEXT tunnelContext =
+        (POVS_TUNFLT_INIT_CONTEXT) context;
+    POVS_SWITCH_CONTEXT switchContext = tunnelContext->switchContext;
+    POVS_VPORT_ENTRY vport = tunnelContext->vport;
+    POVS_MESSAGE msgIn = (POVS_MESSAGE)tunnelContext->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)tunnelContext->outputBuffer;
+    NL_ERROR nlError = NlMapStatusToNlErr(status);
+    LOCK_STATE_EX lockState;
+
+    NdisAcquireRWLockWrite(switchContext->dispatchLock, &lockState, 0);
+
+    if (msgIn && msgOut) {
+        /* Check the received status to reply to the caller. */
+        if (STATUS_SUCCESS == status) {
+            OvsCreateMsgFromVport(vport,
+                                  msgIn,
+                                  msgOut,
+                                  tunnelContext->outputLength,
+                                  switchContext->dpNo);
+
+            *replyLen = msgOut->nlMsg.nlmsgLen;
+        } else {
+            POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR)msgOut;
+
+            NlBuildErrorMsg(msgIn, msgError, nlError);
+            *replyLen = msgError->nlMsg.nlmsgLen;
+        }
+    }
+
+    ASSERT(vport->isAbsentOnHv == TRUE);
+    ASSERT(vport->portNo != OVS_DPPORT_NUMBER_INVALID);
+
+    /* Remove the port from the relevant lists. */
+    switchContext->numNonHvVports--;
+    RemoveEntryList(&vport->ovsNameLink);
+    RemoveEntryList(&vport->portNoLink);
+    RemoveEntryList(&vport->tunnelVportLink);
+
+    if (vport->priv) {
+        OvsFreeMemoryWithTag(vport->priv, OVS_VXLAN_POOL_TAG);
+        vport->priv = NULL;
+    }
+
+    OvsFreeMemoryWithTag(vport, OVS_VPORT_POOL_TAG);
+
+    NdisReleaseRWLock(switchContext->dispatchLock, &lockState);
+}
+
+static VOID
+OvsTunnelVportPendingInit(PVOID context,
+                          NTSTATUS status,
+                          UINT32 *replyLen)
+{
+    POVS_TUNFLT_INIT_CONTEXT tunnelContext =
+        (POVS_TUNFLT_INIT_CONTEXT) context;
+    POVS_VPORT_ENTRY vport = tunnelContext->vport;
+    POVS_MESSAGE msgIn = (POVS_MESSAGE)tunnelContext->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)tunnelContext->outputBuffer;
+    PCHAR portName;
+    ULONG portNameLen = 0;
+    UINT32 portType = 0;
+    NL_ERROR nlError = NL_ERROR_SUCCESS;
+    BOOLEAN error = TRUE;
+
+    do {
+        if (!NT_SUCCESS(status)) {
+            nlError = NlMapStatusToNlErr(status);
+            break;
+        }
+
+        static const NL_POLICY ovsVportPolicy[] = {
+            [OVS_VPORT_ATTR_PORT_NO] = { .type = NL_A_U32, .optional = TRUE },
+            [OVS_VPORT_ATTR_TYPE] = { .type = NL_A_U32, .optional = FALSE },
+            [OVS_VPORT_ATTR_NAME] = { .type = NL_A_STRING, .maxLen = IFNAMSIZ,
+            .optional = FALSE },
+            [OVS_VPORT_ATTR_UPCALL_PID] = { .type = NL_A_UNSPEC,
+            .optional = FALSE },
+            [OVS_VPORT_ATTR_OPTIONS] = { .type = NL_A_NESTED, .optional = TRUE },
+        };
+
+        PNL_ATTR vportAttrs[ARRAY_SIZE(ovsVportPolicy)];
+
+        /* input buffer has been validated while validating write dev op. */
+        ASSERT(msgIn != NULL);
+
+        /* Output buffer has been validated while validating transact dev op. */
+        ASSERT(msgOut != NULL && tunnelContext->outputLength >= sizeof *msgOut);
+
+        if (!NlAttrParse((PNL_MSG_HDR)msgIn,
+            NLMSG_HDRLEN + GENL_HDRLEN + OVS_HDRLEN,
+            NlMsgAttrsLen((PNL_MSG_HDR)msgIn),
+            ovsVportPolicy, ARRAY_SIZE(ovsVportPolicy),
+            vportAttrs, ARRAY_SIZE(vportAttrs))) {
+            nlError = NL_ERROR_INVAL;
+            break;
+        }
+
+        portName = NlAttrGet(vportAttrs[OVS_VPORT_ATTR_NAME]);
+        portNameLen = NlAttrGetSize(vportAttrs[OVS_VPORT_ATTR_NAME]);
+        portType = NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_TYPE]);
+
+        if (vport->portNo != OVS_DPPORT_NUMBER_INVALID) {
+            nlError = NL_ERROR_EXIST;
+            break;
+        }
+
+        vport->ovsState = OVS_STATE_CONNECTED;
+        vport->nicState = NdisSwitchNicStateConnected;
+
+        /*
+         * Allow the vport to be deleted, because there is no
+         * corresponding hyper-v switch part.
+         */
+        vport->isAbsentOnHv = TRUE;
+
+        if (vportAttrs[OVS_VPORT_ATTR_PORT_NO] != NULL) {
+            /*
+             * XXX: when we implement the limit for OVS port number to be
+             * MAXUINT16, we'll need to check the port number received from the
+             * userspace.
+             */
+            vport->portNo =
+                NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_PORT_NO]);
+        } else {
+            vport->portNo =
+                OvsComputeVportNo(gOvsSwitchContext);
+            if (vport->portNo == OVS_DPPORT_NUMBER_INVALID) {
+                nlError = NL_ERROR_NOMEM;
+                break;
+            }
+        }
+
+        /* The ovs port name must be uninitialized. */
+        ASSERT(vport->ovsName[0] == '\0');
+        ASSERT(portNameLen <= OVS_MAX_PORT_NAME_LENGTH);
+
+        RtlCopyMemory(vport->ovsName, portName, portNameLen);
+        /* if we don't have options, then vport->portOptions will be NULL */
+        vport->portOptions = vportAttrs[OVS_VPORT_ATTR_OPTIONS];
+
+        /*
+         * XXX: when we implement OVS_DP_ATTR_USER_FEATURES in datapath,
+         * we'll need to check the OVS_DP_F_VPORT_PIDS flag: if it is set,
+         * it means we have an array of pids, instead of a single pid.
+         * ATM we assume we have one pid only.
+         */
+        vport->upcallPid =
+            NlAttrGetU32(vportAttrs[OVS_VPORT_ATTR_UPCALL_PID]);
+
+        status = InitOvsVportCommon(gOvsSwitchContext, vport);
+        ASSERT(status == STATUS_SUCCESS);
+
+        OvsCreateMsgFromVport(vport,
+                              msgIn,
+                              msgOut,
+                              tunnelContext->outputLength,
+                              gOvsSwitchContext->dpNo);
+
+        *replyLen = msgOut->nlMsg.nlmsgLen;
+
+        error = FALSE;
+    } while (error);
+
+    if (error) {
+        POVS_MESSAGE_ERROR msgError = (POVS_MESSAGE_ERROR) msgOut;
+
+        OvsCleanupVxlanTunnel(NULL, vport, NULL, NULL);
+        OvsFreeMemory(vport);
+
+        NlBuildErrorMsg(msgIn, msgError, nlError);
+        *replyLen = msgError->nlMsg.nlmsgLen;
+    }
+}