datapath-windows: Reply for Flow Flush.

Added changes to send a reply for FLOW_FUSH case. This is needed
as with nithin's transaction reply changes we'll need reply for each
command.

This patch also contains minor fixes for sending replies in
success case as well.

Signed-off-by: Ankur Sharma <ankursharma@vmware.com>
Acked-by: Nithin Raju <nithin@vmware.com>
Signed-off-by: Ben Pfaff <blp@nicira.com>

datapath-windows/ovsext/Flow.c

@@ -290,8 +290,27 @@ OvsFlowNlCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
     /* FLOW_DEL command w/o any key input is a flush case. */
     if ((genlMsgHdr->cmd == OVS_FLOW_CMD_DEL) &&
         (!(nlAttrs[OVS_FLOW_ATTR_KEY]))) {
+
         rc = OvsFlushFlowIoctl(ovsHdr->dp_ifindex);
-        goto done;
+
+       if (rc == STATUS_SUCCESS) {
+            /* XXX: refactor this code. */
+            /* So far so good. Prepare the reply for userspace */
+            NlBufInit(&nlBuf, usrParamsCtx->outputBuffer,
+                      usrParamsCtx->outputLength);
+
+            /* Prepare nl Msg headers */
+            rc = NlFillOvsMsg(&nlBuf, nlMsgHdr->nlmsgType, 0,
+                              nlMsgHdr->nlmsgSeq, nlMsgHdr->nlmsgPid,
+                              genlMsgHdr->cmd, OVS_FLOW_VERSION,
+                              ovsHdr->dp_ifindex);
+
+            if (rc == STATUS_SUCCESS) {
+                *replyLen = msgOut->nlMsg.nlmsgLen;
+            }
+       }
+
+       goto done;
     }
 
     if ((rc = _MapNlToFlowPut(msgIn, nlAttrs[OVS_FLOW_ATTR_KEY],
@@ -342,6 +361,7 @@ OvsFlowNlCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
                                        usrParamsCtx->outputBuffer;
         BuildErrorMsg(msgIn, msgError, nlError);
         *replyLen = msgError->nlMsg.nlmsgLen;
+        rc = STATUS_SUCCESS;
     }
 
     return rc;
@@ -360,6 +380,12 @@ OvsFlowNlGetCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
     NTSTATUS rc = STATUS_SUCCESS;
     NL_ERROR nlError = NL_ERROR_SUCCESS;
     POVS_MESSAGE msgIn = (POVS_MESSAGE)usrParamsCtx->inputBuffer;
+    POVS_MESSAGE msgOut = (POVS_MESSAGE)usrParamsCtx->outputBuffer;
+    PNL_MSG_HDR nlMsgHdr = &(msgIn->nlMsg);
+    PGENL_MSG_HDR genlMsgHdr = &(msgIn->genlMsg);
+    POVS_HDR ovsHdr = &(msgIn->ovsHdr);
+
+    NL_BUFFER nlBuf;
 
     *replyLen = 0;
 
@@ -381,6 +407,23 @@ OvsFlowNlGetCmdHandler(POVS_USER_PARAMS_CONTEXT usrParamsCtx,
                                        usrParamsCtx->outputBuffer;
         BuildErrorMsg(msgIn, msgError, nlError);
         *replyLen = msgError->nlMsg.nlmsgLen;
+        rc = STATUS_SUCCESS;
+        goto done;
+    }
+
+    if (rc == STATUS_SUCCESS) {
+        NlBufInit(&nlBuf, usrParamsCtx->outputBuffer,
+                  usrParamsCtx->outputLength);
+
+        /* Prepare nl Msg headers */
+        rc = NlFillOvsMsg(&nlBuf, nlMsgHdr->nlmsgType, 0,
+                          nlMsgHdr->nlmsgSeq, nlMsgHdr->nlmsgPid,
+                          genlMsgHdr->cmd, OVS_FLOW_VERSION,
+                          ovsHdr->dp_ifindex);
+
+        if (rc == STATUS_SUCCESS) {
+            *replyLen = msgOut->nlMsg.nlmsgLen;
+        }
     }
 
 done: