NetworkServices/IntNetSwitch,Devices/Network/DrvIntNet,Devices/Network/SrvIntNetR0: Don't require a dedicated waiting thread to get notified when there is something to receive but make it possible to register a callback which is called and sends an IPC message instead, bugref:10297

git-svn-id: https://www.virtualbox.org/svn/vbox/trunk@97338 cfe28804-0f27-0410-a406-dd0f0b0b656f

6 files changed, 196 insertions, 111 deletions

diff --git a/include/VBox/intnet.h b/include/VBox/intnet.h
index 451db665c63..da046e37f00 100644
--- a/include/VBox/intnet.h
+++ b/include/VBox/intnet.h
@@ -50,7 +50,17 @@ RT_C_DECLS_BEGIN
 
 /** The userspace internal network service identifier. */
 #if defined(RT_OS_DARWIN) && defined(VBOX_WITH_INTNET_SERVICE_IN_R3)
-# define INTNET_R3_SVC_NAME "org.virtualbox.intnet"
+/** The XPC service identififer. */
+# define INTNET_R3_SVC_NAME                 "org.virtualbox.intnet"
+/** The high 32 bits pattern for the "rc" status code field to recognize errors
+ * where xpc_dictionary_get_int64() might return 0 which could be confused with VINF_SUCCESS. */
+# define INTNET_R3_SVC_RC_PATTERN           ((uint64_t)RT_MAKE_U32_FROM_U8('V', 'B', 'O', 'X'))
+/** Constructs a signd 64bit value for the given 32-bit status code. */
+# define INTNET_R3_SVC_SET_RC(a_rc)         ((INTNET_R3_SVC_RC_PATTERN << 32) | (uint64_t)(a_rc))
+/** Gets the status code from the given 64-bit signed status code value. */
+# define INTNET_R3_SVC_GET_RC(a_RcVal)      ((int32_t)(a_RcVal))
+/** Checks whether the given 64-bit signed status code value encodes a valid IPRT/VBOX status code. */
+# define INTNET_R3_SVC_IS_VALID_RC(a_RcVal) (((a_RcVal) >> 32) == INTNET_R3_SVC_RC_PATTERN)
 #endif
 
 
@@ -1316,6 +1326,23 @@ INTNETR0DECL(int)       IntNetR0IfAbortWait(INTNETIFHANDLE hIf, PSUPDRVSESSION p
 /** @} */
 #endif /* IN_RING0 */
 
+/** 
+ * Callback function for use with IntNetR3Open to signalling incoming data. 
+ *  
+ * @param   hIf     Interface handle.
+ * @param   pvUser  User parameter.
+ */
+typedef DECLCALLBACKTYPE(void, FNINTNETIFRECVAVAIL,(INTNETIFHANDLE hIf, void *pvUser));
+/** Pointer to a FNINTNETIFRECVAVAIL callback. */
+typedef FNINTNETIFRECVAVAIL *PFNINTNETIFRECVAVAIL;
+
+#if defined(VBOX_WITH_INTNET_SERVICE_IN_R3) && defined(IN_RING3)
+INTNETR3DECL(int)       IntNetR3Open(PSUPDRVSESSION pSession, const char *pszNetwork,
+                                     INTNETTRUNKTYPE enmTrunkType, const char *pszTrunk, uint32_t fFlags,
+                                     uint32_t cbSend, uint32_t cbRecv, PFNINTNETIFRECVAVAIL pfnRecvAvail,
+                                     void *pvUserRecvAvail, PINTNETIFHANDLE phIf);
+#endif
+
 RT_C_DECLS_END
 
 #endif /* !VBOX_INCLUDED_intnet_h */
diff --git a/src/VBox/Devices/Network/DrvIntNet.cpp b/src/VBox/Devices/Network/DrvIntNet.cpp
index 54cb251613e..5673fb91ca9 100644
--- a/src/VBox/Devices/Network/DrvIntNet.cpp
+++ b/src/VBox/Devices/Network/DrvIntNet.cpp
@@ -248,15 +248,20 @@ static int drvR3IntNetCallSvc(PDRVINTNET pThis, uint32_t uOperation, void *pvArg
         xpc_dictionary_set_uint64(hObj, "req-id", uOperation);
         xpc_dictionary_set_data(hObj, "req", pvArg, cbArg);
         xpc_object_t hObjReply = xpc_connection_send_message_with_reply_sync(pThis->hXpcCon, hObj);
-        int rc = (int)xpc_dictionary_get_int64(hObjReply, "rc");
+        uint64_t u64Rc = xpc_dictionary_get_uint64(hObjReply, "rc");
+        if (INTNET_R3_SVC_IS_VALID_RC(u64Rc))
+        {
+            size_t cbReply = 0;
+            const void *pvData = xpc_dictionary_get_data(hObjReply, "reply", &cbReply);
+            AssertRelease(cbReply == cbArg);
+            memcpy(pvArg, pvData, cbArg);
+            xpc_release(hObjReply);
 
-        size_t cbReply = 0;
-        const void *pvData = xpc_dictionary_get_data(hObjReply, "reply", &cbReply);
-        AssertRelease(cbReply == cbArg);
-        memcpy(pvArg, pvData, cbArg);
-        xpc_release(hObjReply);
+            return INTNET_R3_SVC_GET_RC(u64Rc);
+        }
 
-        return rc;
+        xpc_release(hObjReply);
+        return VERR_INVALID_STATE;
     }
     else
 #endif
@@ -315,7 +320,12 @@ static int drvR3IntNetMapBufferPointers(PDRVINTNET pThis)
         xpc_dictionary_set_uint64(hObj, "req-id", VMMR0_DO_INTNET_IF_GET_BUFFER_PTRS);
         xpc_dictionary_set_data(hObj, "req", &GetBufferPtrsReq, sizeof(GetBufferPtrsReq));
         xpc_object_t hObjReply = xpc_connection_send_message_with_reply_sync(pThis->hXpcCon, hObj);
-        rc = (int)xpc_dictionary_get_int64(hObjReply, "rc");
+        uint64_t u64Rc = xpc_dictionary_get_uint64(hObjReply, "rc");
+        if (INTNET_R3_SVC_IS_VALID_RC(u64Rc))
+            rc = INTNET_R3_SVC_GET_RC(u64Rc);
+        else
+            rc = VERR_INVALID_STATE;
+
         if (RT_SUCCESS(rc))
         {
             /* Get the shared memory object. */
@@ -326,6 +336,7 @@ static int drvR3IntNetMapBufferPointers(PDRVINTNET pThis)
             else
                 pThis->cbBuf = cbMem;
         }
+
         xpc_release(hObjReply);
     }
     else
diff --git a/src/VBox/Devices/Network/SrvIntNetR0.cpp b/src/VBox/Devices/Network/SrvIntNetR0.cpp
index 25e4997dd27..e19afefa14b 100644
--- a/src/VBox/Devices/Network/SrvIntNetR0.cpp
+++ b/src/VBox/Devices/Network/SrvIntNetR0.cpp
@@ -244,11 +244,18 @@ typedef struct INTNETIF
     PINTNETBUF              pIntBufDefault;
     /** Pointer to ring-3 mapping of the default exchange buffer. */
     R3PTRTYPE(PINTNETBUF)   pIntBufDefaultR3;
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
     /** Event semaphore which a receiver/consumer thread will sleep on while
      * waiting for data to arrive. */
     RTSEMEVENT volatile     hRecvEvent;
     /** Number of threads sleeping on the event semaphore. */
     uint32_t volatile       cSleepers;
+#else
+    /** The callback to call when there is something to receive/consume. */
+    PFNINTNETIFRECVAVAIL    pfnRecvAvail;
+    /** Opaque user data to pass to the receive avail callback (pfnRecvAvail). */
+    void                   *pvUserRecvAvail;
+#endif
     /** The interface handle.
      * When this is INTNET_HANDLE_INVALID a sleeper which is waking up
      * should return with the appropriate error condition. */
@@ -2832,6 +2839,19 @@ static int intnetR0RingWriteFrame(PINTNETRINGBUF pRingBuf, PCINTNETSG pSG, PCRTM
 }
 
 
+/** 
+ * Notifies consumers of incoming data from @a pIf that data is available.
+ */ 
+DECL_FORCE_INLINE(void) intnetR0IfNotifyRecv(PINTNETIF pIf)
+{
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
+    RTSemEventSignal(pIf->hRecvEvent);
+#else
+    pIf->pfnRecvAvail(pIf->hIf, pIf->pvUserRecvAvail);
+#endif
+}
+
+
 /**
  * Sends a frame to a specific interface.
  *
@@ -2851,7 +2871,7 @@ static void intnetR0IfSend(PINTNETIF pIf, PINTNETIF pIfSender, PINTNETSG pSG, PC
     if (RT_SUCCESS(rc))
     {
         pIf->cYields = 0;
-        RTSemEventSignal(pIf->hRecvEvent);
+        intnetR0IfNotifyRecv(pIf);
         return;
     }
 
@@ -2869,7 +2889,7 @@ static void intnetR0IfSend(PINTNETIF pIf, PINTNETIF pIfSender, PINTNETSG pSG, PC
         unsigned cYields = 2;
         while (--cYields > 0)
         {
-            RTSemEventSignal(pIf->hRecvEvent);
+            intnetR0IfNotifyRecv(pIf);
             RTThreadYield();
 
             RTSpinlockAcquire(pIf->hRecvInSpinlock);
@@ -2878,7 +2898,7 @@ static void intnetR0IfSend(PINTNETIF pIf, PINTNETIF pIfSender, PINTNETSG pSG, PC
             if (RT_SUCCESS(rc))
             {
                 STAM_REL_COUNTER_INC(&pIf->pIntBuf->cStatYieldsOk);
-                RTSemEventSignal(pIf->hRecvEvent);
+                intnetR0IfNotifyRecv(pIf);
                 return;
             }
             pIf->cYields++;
@@ -2888,7 +2908,7 @@ static void intnetR0IfSend(PINTNETIF pIf, PINTNETIF pIfSender, PINTNETSG pSG, PC
 
     /* ok, the frame is lost. */
     STAM_REL_COUNTER_INC(&pIf->pIntBuf->cStatLost);
-    RTSemEventSignal(pIf->hRecvEvent);
+    intnetR0IfNotifyRecv(pIf);
 }
 
 
@@ -4666,7 +4686,11 @@ INTNETR0DECL(int) IntNetR0IfWait(INTNETIFHANDLE hIf, PSUPDRVSESSION pSession, ui
         return VERR_INVALID_HANDLE;
     }
 
-    const RTSEMEVENT hRecvEvent   = pIf->hRecvEvent;
+#if defined(VBOX_WITH_INTNET_SERVICE_IN_R3) && defined(IN_RING3)
+    AssertReleaseFailed(); /* Should never be called. */
+    return VERR_NOT_SUPPORTED;
+#else
+    const RTSEMEVENT hRecvEvent  = pIf->hRecvEvent;
     const bool       fNoMoreWaits = ASMAtomicUoReadBool(&pIf->fNoMoreWaits);
     RTNATIVETHREAD   hDtorThrd;
     ASMAtomicReadHandle(&pIf->hDestructorThread, &hDtorThrd);
@@ -4720,6 +4744,7 @@ INTNETR0DECL(int) IntNetR0IfWait(INTNETIFHANDLE hIf, PSUPDRVSESSION pSession, ui
 
     Log4(("IntNetR0IfWait: returns %Rrc\n", rc));
     return rc;
+#endif
 }
 
 
@@ -4764,6 +4789,10 @@ INTNETR0DECL(int) IntNetR0IfAbortWait(INTNETIFHANDLE hIf, PSUPDRVSESSION pSessio
         return VERR_INVALID_HANDLE;
     }
 
+#if defined(VBOX_WITH_INTNET_SERVICE_IN_R3) && defined(IN_RING3)
+    AssertReleaseFailed();
+    return VERR_NOT_SUPPORTED;
+#else
     const RTSEMEVENT hRecvEvent  = pIf->hRecvEvent;
     RTNATIVETHREAD   hDtorThrd;
     ASMAtomicReadHandle(&pIf->hDestructorThread, &hDtorThrd);
@@ -4806,6 +4835,7 @@ INTNETR0DECL(int) IntNetR0IfAbortWait(INTNETIFHANDLE hIf, PSUPDRVSESSION pSessio
 
     Log4(("IntNetR0IfWait: returns %Rrc\n", VINF_SUCCESS));
     return VINF_SUCCESS;
+#endif
 }
 
 
@@ -4850,6 +4880,7 @@ INTNETR0DECL(int) IntNetR0IfClose(INTNETIFHANDLE hIf, PSUPDRVSESSION pSession)
     /* Mark the handle as freed so intnetR0IfDestruct won't free it again. */
     ASMAtomicWriteU32(&pIf->hIf, INTNET_HANDLE_INVALID);
 
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
     /*
      * Signal the event semaphore to wake up any threads in IntNetR0IfWait
      * and give them a moment to get out and release the interface.
@@ -4861,6 +4892,7 @@ INTNETR0DECL(int) IntNetR0IfClose(INTNETIFHANDLE hIf, PSUPDRVSESSION pSession)
         RTThreadYield();
     }
     RTSemEventSignal(pIf->hRecvEvent);
+#endif
 
     /*
      * Release the references to the interface object (handle + free lookup).
@@ -4999,6 +5031,7 @@ static DECLCALLBACK(void) intnetR0IfDestruct(void *pvObj, void *pvUser1, void *p
 
     RTSemMutexRelease(pIntNet->hMtxCreateOpenDestroy);
 
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
     /*
      * Wakeup anyone waiting on this interface. (Kind of unlikely, but perhaps
      * not quite impossible.)
@@ -5030,6 +5063,7 @@ static DECLCALLBACK(void) intnetR0IfDestruct(void *pvObj, void *pvUser1, void *p
         RTSemEventDestroy(hRecvEvent);
         pIf->hRecvEvent = NIL_RTSEMEVENT;
     }
+#endif
 
     /*
      * Unmap user buffer.
@@ -5079,17 +5113,19 @@ static DECLCALLBACK(int) intnetR0TrunkReconnectThread(RTTHREAD hThread, void *pv
  * opened so the interface destructor can close it.
  *
  * @returns VBox status code.
- * @param   pNetwork    The network, referenced.  The reference is consumed on
- *                      success.
- * @param   pSession    The session handle.
- * @param   cbSend      The size of the send buffer.
- * @param   cbRecv      The size of the receive buffer.
- * @param   fFlags      The open network flags.
- * @param   phIf        Where to store the interface handle.
+ * @param   pNetwork        The network, referenced.  The reference is consumed
+ *                          on success.
+ * @param   pSession        The session handle.
+ * @param   cbSend          The size of the send buffer.
+ * @param   cbRecv          The size of the receive buffer.
+ * @param   fFlags          The open network flags.
+ * @param   pfnRecvAvail    The receive available callback to call instead of
+ *                          signalling the semaphore (R3 service only).
+ * @param   pvUser          The opaque user data to pass to the callback.
+ * @param   phIf            Where to store the interface handle.
  */
-static int intnetR0NetworkCreateIf(PINTNETNETWORK pNetwork, PSUPDRVSESSION pSession,
-                                   unsigned cbSend, unsigned cbRecv, uint32_t fFlags,
-                                   PINTNETIFHANDLE phIf)
+static int intnetR0NetworkCreateIf(PINTNETNETWORK pNetwork, PSUPDRVSESSION pSession, unsigned cbSend, unsigned cbRecv,
+                                   uint32_t fFlags, PFNINTNETIFRECVAVAIL pfnRecvAvail, void *pvUser, PINTNETIFHANDLE phIf)
 {
     LogFlow(("intnetR0NetworkCreateIf: pNetwork=%p pSession=%p cbSend=%u cbRecv=%u fFlags=%#x phIf=%p\n",
              pNetwork, pSession, cbSend, cbRecv, fFlags, phIf));
@@ -5099,6 +5135,11 @@ static int intnetR0NetworkCreateIf(PINTNETNETWORK pNetwork, PSUPDRVSESSION pSess
      */
     AssertPtr(pNetwork);
     AssertPtr(phIf);
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
+    Assert(pfnRecvAvail == NULL);
+    Assert(pvUser == NULL);
+    RT_NOREF(pfnRecvAvail, pvUser);
+#endif
 
     /*
      * Adjust the flags with defaults for the interface policies.
@@ -5135,7 +5176,12 @@ static int intnetR0NetworkCreateIf(PINTNETNETWORK pNetwork, PSUPDRVSESSION pSess
     //pIf->pIntBufR3        = NIL_RTR3PTR;
     //pIf->pIntBufDefault   = 0;
     //pIf->pIntBufDefaultR3 = NIL_RTR3PTR;
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
     pIf->hRecvEvent         = NIL_RTSEMEVENT;
+#else
+    pIf->pfnRecvAvail       = pfnRecvAvail;
+    pIf->pvUserRecvAvail    = pvUser;
+#endif
     //pIf->cSleepers        = 0;
     pIf->hIf                = INTNET_HANDLE_INVALID;
     pIf->hDestructorThread  = NIL_RTNATIVETHREAD;
@@ -5153,8 +5199,10 @@ static int intnetR0NetworkCreateIf(PINTNETNETWORK pNetwork, PSUPDRVSESSION pSess
                                      !!(pNetwork->fFlags & INTNET_OPEN_FLAGS_SHARED_MAC_ON_WIRE));
     if (RT_SUCCESS(rc))
         rc = intnetR0AllocDstTab(pNetwork->MacTab.cEntriesAllocated, (PINTNETDSTTAB *)&pIf->pDstTab);
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
     if (RT_SUCCESS(rc))
         rc = RTSemEventCreate((PRTSEMEVENT)&pIf->hRecvEvent);
+#endif
     if (RT_SUCCESS(rc))
         rc = RTSpinlockCreate(&pIf->hRecvInSpinlock, RTSPINLOCK_FLAGS_INTERRUPT_SAFE, "hRecvInSpinlock");
     if (RT_SUCCESS(rc))
@@ -5247,8 +5295,13 @@ static int intnetR0NetworkCreateIf(PINTNETNETWORK pNetwork, PSUPDRVSESSION pSess
 
     RTSpinlockDestroy(pIf->hRecvInSpinlock);
     pIf->hRecvInSpinlock = NIL_RTSPINLOCK;
+#if !defined(VBOX_WITH_INTNET_SERVICE_IN_R3) || !defined(IN_RING3)
     RTSemEventDestroy(pIf->hRecvEvent);
     pIf->hRecvEvent = NIL_RTSEMEVENT;
+#else
+    pIf->pfnRecvAvail    = NULL;
+    pIf->pvUserRecvAvail = NULL;
+#endif
     RTMemFree(pIf->pDstTab);
     for (int i = kIntNetAddrType_Invalid + 1; i < kIntNetAddrType_End; i++)
         intnetR0IfAddrCacheDestroy(&pIf->aAddrCache[i]);
@@ -6593,14 +6646,19 @@ static int intnetR0CreateNetwork(PINTNET pIntNet, PSUPDRVSESSION pSession, const
  * @param   enmTrunkType    The trunk type.
  * @param   pszTrunk        The trunk name. Its meaning is specific to the type.
  * @param   fFlags          Flags, see INTNET_OPEN_FLAGS_*.
- * @param   fRestrictAccess Whether new participants should be subjected to access check or not.
+ * @param   fRestrictAccess Whether new participants should be subjected to
+ *                          access check or not.
  * @param   cbSend          The send buffer size.
  * @param   cbRecv          The receive buffer size.
+ * @param   pfnRecvAvail    The receive available callback to call instead of 
+ *                          signalling the semaphore (R3 service only).
+ * @param   pvUser          The opaque user data to pass to the callback.
  * @param   phIf            Where to store the handle to the network interface.
  */
 INTNETR0DECL(int) IntNetR0Open(PSUPDRVSESSION pSession, const char *pszNetwork,
                                INTNETTRUNKTYPE enmTrunkType, const char *pszTrunk, uint32_t fFlags,
-                               uint32_t cbSend, uint32_t cbRecv, PINTNETIFHANDLE phIf)
+                               uint32_t cbSend, uint32_t cbRecv, PFNINTNETIFRECVAVAIL pfnRecvAvail, void *pvUser, 
+                               PINTNETIFHANDLE phIf)
 {
     LogFlow(("IntNetR0Open: pSession=%p pszNetwork=%p:{%s} enmTrunkType=%d pszTrunk=%p:{%s} fFlags=%#x cbSend=%u cbRecv=%u phIf=%p\n",
              pSession, pszNetwork, pszNetwork, enmTrunkType, pszTrunk, pszTrunk, fFlags, cbSend, cbRecv, phIf));
@@ -6674,7 +6732,7 @@ INTNETR0DECL(int) IntNetR0Open(PSUPDRVSESSION pSession, const char *pszNetwork,
     rc = intnetR0OpenNetwork(pIntNet, pSession, pszNetwork, enmTrunkType, pszTrunk, fFlags, &pNetwork);
     if (RT_SUCCESS(rc))
     {
-        rc = intnetR0NetworkCreateIf(pNetwork, pSession, cbSend, cbRecv, fFlags, phIf);
+        rc = intnetR0NetworkCreateIf(pNetwork, pSession, cbSend, cbRecv, fFlags, pfnRecvAvail, pvUser, phIf);
         if (RT_SUCCESS(rc))
         {
             intnetR0AdaptOpenNetworkFlags(pNetwork, fFlags);
@@ -6688,7 +6746,7 @@ INTNETR0DECL(int) IntNetR0Open(PSUPDRVSESSION pSession, const char *pszNetwork,
         rc = intnetR0CreateNetwork(pIntNet, pSession, pszNetwork, enmTrunkType, pszTrunk, fFlags, &pNetwork);
         if (RT_SUCCESS(rc))
         {
-            rc = intnetR0NetworkCreateIf(pNetwork, pSession, cbSend, cbRecv, fFlags, phIf);
+            rc = intnetR0NetworkCreateIf(pNetwork, pSession, cbSend, cbRecv, fFlags, pfnRecvAvail, pvUser, phIf);
             if (RT_FAILURE(rc))
                 SUPR0ObjRelease(pNetwork->pvObj, pSession);
         }
@@ -6712,8 +6770,19 @@ INTNETR0DECL(int) IntNetR0OpenReq(PSUPDRVSESSION pSession, PINTNETOPENREQ pReq)
     if (RT_UNLIKELY(pReq->Hdr.cbReq != sizeof(*pReq)))
         return VERR_INVALID_PARAMETER;
     return IntNetR0Open(pSession, &pReq->szNetwork[0], pReq->enmTrunkType, pReq->szTrunk,
-                        pReq->fFlags, pReq->cbSend, pReq->cbRecv, &pReq->hIf);
+                        pReq->fFlags, pReq->cbSend, pReq->cbRecv, NULL /*pfnRecvAvail*/, NULL /*pvUser*/, &pReq->hIf);
+}
+
+
+#if defined(VBOX_WITH_INTNET_SERVICE_IN_R3) && defined(IN_RING3)
+INTNETR3DECL(int) IntNetR3Open(PSUPDRVSESSION pSession, const char *pszNetwork,
+                               INTNETTRUNKTYPE enmTrunkType, const char *pszTrunk, uint32_t fFlags,
+                               uint32_t cbSend, uint32_t cbRecv, PFNINTNETIFRECVAVAIL pfnRecvAvail, void *pvUser, 
+                               PINTNETIFHANDLE phIf)
+{
+    return IntNetR0Open(pSession, pszNetwork, enmTrunkType, pszTrunk, fFlags, cbSend, cbRecv, pfnRecvAvail, pvUser, phIf);
 }
+#endif
 
 
 /**
diff --git a/src/VBox/Devices/Network/testcase/tstIntNetR0.cpp b/src/VBox/Devices/Network/testcase/tstIntNetR0.cpp
index c67643a37e7..9f087a31558 100644
--- a/src/VBox/Devices/Network/testcase/tstIntNetR0.cpp
+++ b/src/VBox/Devices/Network/testcase/tstIntNetR0.cpp
@@ -446,16 +446,16 @@ typedef TSTSTATE *PTSTSTATE;
 static int tstOpenInterfaces(PTSTSTATE pThis, const char *pszNetwork, uint32_t cbSend, uint32_t cbRecv)
 {
     pThis->hIf0 = INTNET_HANDLE_INVALID;
-    RTTESTI_CHECK_RC_OK_RET(IntNetR0Open(g_pSession, pszNetwork, kIntNetTrunkType_None, "",
-                                         0/*fFlags*/, cbSend, cbRecv, &pThis->hIf0), rcCheck);
+    RTTESTI_CHECK_RC_OK_RET(IntNetR0Open(g_pSession, pszNetwork, kIntNetTrunkType_None, "", 0/*fFlags*/, cbSend, cbRecv, 
+                                         NULL /*pfnRecvAvail*/, NULL /*pvUser*/, &pThis->hIf0), rcCheck);
     RTTESTI_CHECK_RET(pThis->hIf0 != INTNET_HANDLE_INVALID, VERR_INTERNAL_ERROR);
     RTTESTI_CHECK_RC_RET(IntNetR0IfGetBufferPtrs(pThis->hIf0, g_pSession, &pThis->pBuf0, NULL), VINF_SUCCESS, rcCheck);
     RTTESTI_CHECK_RET(pThis->pBuf0, VERR_INTERNAL_ERROR);
 
 
     pThis->hIf1 = INTNET_HANDLE_INVALID;
-    RTTESTI_CHECK_RC_OK_RET(IntNetR0Open(g_pSession, pszNetwork, kIntNetTrunkType_None, "",
-                                         0/*fFlags*/, cbSend, cbRecv, &pThis->hIf1), rcCheck);
+    RTTESTI_CHECK_RC_OK_RET(IntNetR0Open(g_pSession, pszNetwork, kIntNetTrunkType_None, "", 0/*fFlags*/, cbSend, cbRecv, 
+                                         NULL /*pfnRecvAvail*/, NULL /*pvUser*/, &pThis->hIf1), rcCheck);
     RTTESTI_CHECK_RET(pThis->hIf1 != INTNET_HANDLE_INVALID, VERR_INTERNAL_ERROR);
     RTTESTI_CHECK_RC_RET(IntNetR0IfGetBufferPtrs(pThis->hIf1, g_pSession, &pThis->pBuf1, NULL), VINF_SUCCESS, rcCheck);
     RTTESTI_CHECK_RET(pThis->pBuf1, VERR_INTERNAL_ERROR);
diff --git a/src/VBox/NetworkServices/IntNetSwitch/Makefile.kmk b/src/VBox/NetworkServices/IntNetSwitch/Makefile.kmk
index 76996ab9b2c..e48e89494fd 100644
--- a/src/VBox/NetworkServices/IntNetSwitch/Makefile.kmk
+++ b/src/VBox/NetworkServices/IntNetSwitch/Makefile.kmk
@@ -39,9 +39,10 @@ VBoxIntNetSwitch_DEFS      = KBUILD_TYPE="$(KBUILD_TYPE)"
 else
 VBoxIntNetSwitch_DEFS      = KBUILD_TYPE=\"$(KBUILD_TYPE)\"
 endif
+VBoxIntNetSwitch_DEFS     += VBOX_WITH_INTNET_SERVICE_IN_R3
 VBoxIntNetSwitch_INST.darwin = $(VBoxIntNetSwitch.xpc_INST)/MacOS/
 VBoxIntNetSwitch_SOURCES = \
-	main.cpp \
+	VBoxIntNetSwitch.cpp \
 	SrvIntNetWrapper.cpp
 VBoxIntNetSwitch_LIBS = $(LIB_RUNTIME)
 VBoxIntNetSwitch_LDFLAGS.darwin = \
diff --git a/src/VBox/NetworkServices/IntNetSwitch/main.cpp b/src/VBox/NetworkServices/IntNetSwitch/VBoxIntNetSwitch.cpp
index fe946946b6a..1cb3c3db271 100644
--- a/src/VBox/NetworkServices/IntNetSwitch/main.cpp
+++ b/src/VBox/NetworkServices/IntNetSwitch/VBoxIntNetSwitch.cpp
@@ -52,6 +52,11 @@
 
 
 /*********************************************************************************************************************************
+*   Defined Constants And Macros                                                                                                 *
+*********************************************************************************************************************************/
+
+
+/*********************************************************************************************************************************
 *   Structures and Typedefs                                                                                                      *
 *********************************************************************************************************************************/
 
@@ -115,14 +120,12 @@ typedef struct SUPDRVSESSION
     PSUPDRVUSAGE volatile           pUsage;
     /** The XPC connection handle for this session. */
     xpc_connection_t                hXpcCon;
-    /** The receive wait thread. */
-    RTTHREAD                        hThrdRecv;
     /** The intnet interface handle to wait on. */
     INTNETIFHANDLE                  hIfWait;
-    /** The event semaphore for the receive thread. */
-    RTSEMEVENT                      hEvtRecv;
-    /** Flag whether to terminate the receive thread. */
-    bool volatile                   fTerminate;
+    /** Flag whether a receive wait was initiated. */
+    bool volatile                   fRecvWait;
+    /** Flag whether there is something to receive. */
+    bool volatile                   fRecvAvail;
 } SUPDRVSESSION;
 
 
@@ -356,24 +359,12 @@ static uint32_t intnetR3SessionDestroy(PSUPDRVSESSION pSession)
 {
     PSUPDRVDEVEXT pDevExt = pSession->pDevExt;
     uint32_t cRefs = ASMAtomicDecU32(&pDevExt->cRefs);
+    xpc_transaction_end();
     xpc_connection_set_context(pSession->hXpcCon, NULL);
     xpc_connection_cancel(pSession->hXpcCon);
     pSession->hXpcCon = NULL;
-    xpc_transaction_end();
-
-    /* Tear down the receive wait thread. */
-    ASMAtomicXchgBool(&pSession->fTerminate, true);
-    RTSemEventSignal(pSession->hEvtRecv);
-
-    if (pSession->hThrdRecv != NIL_RTTHREAD)
-    {
-        int rc = RTThreadWait(pSession->hThrdRecv, 5000, NULL);
-        AssertRC(rc);
-        pSession->hThrdRecv = NIL_RTTHREAD;
-    }
 
-    RTSemEventDestroy(pSession->hEvtRecv);
-    pSession->hEvtRecv = NIL_RTSEMEVENT;
+    ASMAtomicXchgBool(&pSession->fRecvAvail, true);
 
     if (pSession->pUsage)
     {
@@ -421,7 +412,7 @@ static uint32_t intnetR3SessionDestroy(PSUPDRVSESSION pSession)
         }
 
         RTCritSectLeave(&pDevExt->CritSect);
-        AssertMsg(!pSession->pUsage, ("Some buster reregistered an object during desturction!\n"));
+        AssertMsg(!pSession->pUsage, ("Some buster reregistered an object during destruction!\n"));
     }
 
     RTMemFree(pSession);
@@ -430,42 +421,21 @@ static uint32_t intnetR3SessionDestroy(PSUPDRVSESSION pSession)
 
 
 /**
- * Asynchronous I/O thread for handling receive.
- *
- * @returns VINF_SUCCESS (ignored).
- * @param   hThreadSelf     Thread handle.
- * @param   pvUser          Pointer to a DRVINTNET structure.
+ * Data available in th receive buffer callback.
  */
-static DECLCALLBACK(int) intnetR3RecvThread(RTTHREAD hThreadSelf, void *pvUser)
+static DECLCALLBACK(void) intnetR3RecvAvail(INTNETIFHANDLE hIf, void *pvUser)
 {
-    RT_NOREF(hThreadSelf);
+    RT_NOREF(hIf);
     PSUPDRVSESSION pSession = (PSUPDRVSESSION)pvUser;
 
-    for (;;)
+    if (ASMAtomicXchgBool(&pSession->fRecvWait, false))
     {
-        if (pSession->fTerminate)
-            break;
-
-        RTSemEventWait(pSession->hEvtRecv, RT_INDEFINITE_WAIT);
-        if (pSession->fTerminate)
-            break;
-
-        int rc = IntNetR0IfWait(pSession->hIfWait, pSession, 30000); /* 30s - don't wait forever, timeout now and then. */
-        if (RT_SUCCESS(rc))
-        {
-            /* Send an empty message. */
-            xpc_object_t hObjPoke = xpc_dictionary_create(NULL, NULL, 0);
-            xpc_connection_send_message(pSession->hXpcCon, hObjPoke);
-        }
-        else if (   rc != VERR_TIMEOUT
-                 && rc != VERR_INTERRUPTED)
-        {
-            LogFlow(("intnetR3RecvThread: returns %Rrc\n", rc));
-            return rc;
-        }
+        /* Send an empty message. */
+        xpc_object_t hObjPoke = xpc_dictionary_create(NULL, NULL, 0);
+        xpc_connection_send_message(pSession->hXpcCon, hObjPoke);
     }
-
-    return VINF_SUCCESS;
+    else
+        ASMAtomicXchgBool(&pSession->fRecvAvail, true);
 }
 
 
@@ -499,7 +469,9 @@ static void intnetR3RequestProcess(xpc_connection_t hCon, xpc_object_t hObj, PSU
             {
                 if (cbReq == sizeof(INTNETOPENREQ))
                 {
-                    rc = IntNetR0OpenReq(pSession, &ReqReply.OpenReq);
+                    rc = IntNetR3Open(pSession, &ReqReply.OpenReq.szNetwork[0], ReqReply.OpenReq.enmTrunkType, ReqReply.OpenReq.szTrunk,
+                                      ReqReply.OpenReq.fFlags, ReqReply.OpenReq.cbSend, ReqReply.OpenReq.cbRecv,
+                                      intnetR3RecvAvail, pSession, &ReqReply.OpenReq.hIf);
                     cbReply = sizeof(INTNETOPENREQ);
                 }
                 else
@@ -524,10 +496,16 @@ static void intnetR3RequestProcess(xpc_connection_t hCon, xpc_object_t hObj, PSU
                     rc = IntNetR0IfGetBufferPtrsReq(pSession, &ReqReply.IfGetBufferPtrsReq);
                     /* This is special as we need to return a shared memory segment. */
                     xpc_object_t hObjReply = xpc_dictionary_create_reply(hObj);
-                    xpc_dictionary_set_int64(hObjReply, "rc", rc);
                     xpc_object_t hObjShMem = xpc_shmem_create(ReqReply.IfGetBufferPtrsReq.pRing3Buf, ReqReply.IfGetBufferPtrsReq.pRing3Buf->cbBuf);
-                    xpc_dictionary_set_value(hObjReply, "buf-ptr", hObjShMem);
-                    xpc_release(hObjShMem);
+                    if (hObjShMem)
+                    {
+                        xpc_dictionary_set_value(hObjReply, "buf-ptr", hObjShMem);
+                        xpc_release(hObjShMem);
+                    }
+                    else
+                        rc = VERR_NO_MEMORY;
+
+                    xpc_dictionary_set_uint64(hObjReply, "rc", INTNET_R3_SVC_SET_RC(rc));
                     xpc_connection_send_message(hCon, hObjReply);
                     return;
                 }
@@ -583,8 +561,15 @@ static void intnetR3RequestProcess(xpc_connection_t hCon, xpc_object_t hObj, PSU
             {
                 if (cbReq == sizeof(INTNETIFWAITREQ))
                 {
-                    pSession->hIfWait = ReqReply.IfWaitReq.hIf; /* Asynchronous. */
-                    rc = RTSemEventSignal(pSession->hEvtRecv);
+                    ASMAtomicXchgBool(&pSession->fRecvWait, true);
+                    if (ASMAtomicXchgBool(&pSession->fRecvAvail, false))
+                    {
+                        ASMAtomicXchgBool(&pSession->fRecvWait, false);
+
+                        /* Send an empty message. */
+                        xpc_object_t hObjPoke = xpc_dictionary_create(NULL, NULL, 0);
+                        xpc_connection_send_message(pSession->hXpcCon, hObjPoke);
+                    }
                     return;
                 }
                 else
@@ -595,7 +580,13 @@ static void intnetR3RequestProcess(xpc_connection_t hCon, xpc_object_t hObj, PSU
             {
                 if (cbReq == sizeof(INTNETIFABORTWAITREQ))
                 {
-                    rc = IntNetR0IfAbortWaitReq(pSession, &ReqReply.IfAbortWaitReq);
+                    ASMAtomicXchgBool(&pSession->fRecvWait, false);
+                    if (ASMAtomicXchgBool(&pSession->fRecvAvail, false))
+                    {
+                        /* Send an empty message. */
+                        xpc_object_t hObjPoke = xpc_dictionary_create(NULL, NULL, 0);
+                        xpc_connection_send_message(pSession->hXpcCon, hObjPoke);
+                    }
                     cbReply = sizeof(INTNETIFABORTWAITREQ);
                 }
                 else
@@ -608,7 +599,7 @@ static void intnetR3RequestProcess(xpc_connection_t hCon, xpc_object_t hObj, PSU
     }
 
     xpc_object_t hObjReply = xpc_dictionary_create_reply(hObj);
-    xpc_dictionary_set_int64(hObjReply, "rc", rc);
+    xpc_dictionary_set_uint64(hObjReply, "rc", INTNET_R3_SVC_SET_RC(rc));
     xpc_dictionary_set_data(hObjReply, "reply", &ReqReply, cbReply);
     xpc_connection_send_message(hCon, hObjReply);
 }
@@ -645,24 +636,10 @@ DECLCALLBACK(void) xpcConnHandler(xpc_connection_t hXpcCon)
         pSession->pDevExt = &g_DevExt;
         pSession->hXpcCon = hXpcCon;
 
-        int rc = RTSemEventCreate(&pSession->hEvtRecv);
-        if (RT_SUCCESS(rc))
-        {
-            rc = RTThreadCreate(&pSession->hThrdRecv, intnetR3RecvThread, pSession, 0,
-                                RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "INTNET-RECV");
-            if (RT_SUCCESS(rc))
-            {
-                xpc_connection_set_context(hXpcCon, pSession);
-                xpc_connection_resume(hXpcCon);
-                xpc_transaction_begin();
-                ASMAtomicIncU32(&g_DevExt.cRefs);
-                return;
-            }
-
-            RTSemEventDestroy(pSession->hEvtRecv);
-        }
-
-        RTMemFree(pSession);
+        xpc_connection_set_context(hXpcCon, pSession);
+        xpc_connection_activate(hXpcCon);
+        xpc_transaction_begin();
+        ASMAtomicIncU32(&g_DevExt.cRefs);
     }
 }