diff --git a/drivers/staging/unisys/channels/channel.c b/drivers/staging/unisys/channels/channel.c
index ade2fe0da154..b4bdee4b575b 100644
--- a/drivers/staging/unisys/channels/channel.c
+++ b/drivers/staging/unisys/channels/channel.c
@@ -75,7 +75,7 @@ visor_signal_insert(CHANNEL_HEADER __iomem *pChannel, u32 Queue, void *pSignal)
 		(head * readl(&pqhdr->SignalSize));
 	memcpy_toio(psignal, pSignal, readl(&pqhdr->SignalSize));
 
-	VolatileBarrier();
+	mb(); /* channel synch */
 	writel(head, &pqhdr->Head);
 
 	writeq(readq(&pqhdr->NumSignalsSent) + 1, &pqhdr->NumSignalsSent);
@@ -128,7 +128,7 @@ visor_signal_remove(CHANNEL_HEADER __iomem *pChannel, u32 Queue, void *pSignal)
 		(tail * readl(&pqhdr->SignalSize));
 	memcpy_fromio(pSignal, psource, readl(&pqhdr->SignalSize));
 
-	VolatileBarrier();
+	mb(); /* channel synch */
 	writel(tail, &pqhdr->Tail);
 
 	writeq(readq(&pqhdr->NumSignalsReceived) + 1,
@@ -186,7 +186,7 @@ SignalRemoveAll(pCHANNEL_HEADER pChannel, u32 Queue, void *pSignal)
 		memcpy((char *) pSignal + (pqhdr->SignalSize * signalCount),
 		       psource, pqhdr->SignalSize);
 
-		VolatileBarrier();
+		mb(); /* channel synch */
 		pqhdr->Tail = tail;
 
 		signalCount++;
diff --git a/drivers/staging/unisys/common-spar/include/channels/channel.h b/drivers/staging/unisys/common-spar/include/channels/channel.h
index 15a8d6b35dac..bc923336fabd 100644
--- a/drivers/staging/unisys/common-spar/include/channels/channel.h
+++ b/drivers/staging/unisys/common-spar/include/channels/channel.h
@@ -157,7 +157,7 @@ ULTRA_CHANNELCLI_STRING(u32 v)
 			      PathName_Last_N_Nodes(__FILE__, 4), __LINE__); \
 		writel(newstate, &((CHANNEL_HEADER __iomem *) \
 				   (pChan))->CliStateOS);		\
-		MEMORYBARRIER;						\
+		mb(); /* required for channel synch */			\
 	} while (0)
 
 #define ULTRA_CHANNEL_CLIENT_ACQUIRE_OS(pChan, chanId, logCtx)	\
@@ -458,7 +458,7 @@ ULTRA_channel_client_acquire_os(void __iomem *pChannel, u8 *chanId,
 			      CHANNELCLI_OWNED,
 			      PathName_Last_N_Nodes((u8 *) file, 4), line);
 		writel(CHANNELCLI_OWNED, &pChan->CliStateOS);
-		MEMORYBARRIER;
+		mb(); /* required for channel synch */
 	}
 	if (readl(&pChan->CliStateOS) == CHANNELCLI_OWNED) {
 		if (readb(&pChan->CliErrorOS) != 0) {
@@ -502,7 +502,7 @@ ULTRA_channel_client_acquire_os(void __iomem *pChannel, u8 *chanId,
 		return 0;
 	}
 	writel(CHANNELCLI_BUSY, &pChan->CliStateOS);
-	MEMORYBARRIER;
+	mb(); /* required for channel synch */
 	if (readl(&pChan->CliStateBoot) == CHANNELCLI_BUSY) {
 		if ((readb(&pChan->CliErrorOS)
 		     & ULTRA_CLIERROROS_THROTTLEMSG_BUSY) == 0) {
@@ -521,7 +521,7 @@ ULTRA_channel_client_acquire_os(void __iomem *pChannel, u8 *chanId,
 		}
 		/* reset busy */
 		writel(CHANNELCLI_ATTACHED, &pChan->CliStateOS);
-		MEMORYBARRIER;
+		mb(); /* required for channel synch */
 		return 0;
 	}
 	if (readb(&pChan->CliErrorOS) != 0) {
diff --git a/drivers/staging/unisys/include/commontypes.h b/drivers/staging/unisys/include/commontypes.h
index 53ac77053340..34b31ad7b934 100644
--- a/drivers/staging/unisys/include/commontypes.h
+++ b/drivers/staging/unisys/include/commontypes.h
@@ -30,8 +30,6 @@ typedef u64 GUEST_PHYSICAL_ADDRESS;
 #define INLINE inline
 #define OFFSETOF offsetof
 
-#define MEMORYBARRIER mb()
-
 #define CHANNEL_GUID_MISMATCH(chType, chName, field, expected, actual, fil, \
 			      lin, logCtx)				\
 	do {								\
@@ -63,7 +61,5 @@ typedef u64 GUEST_PHYSICAL_ADDRESS;
 		      LineNumber, Str, args...)				\
 	pr_info(Str, ## args)
 
-#define VolatileBarrier() MEMORYBARRIER
-
 #endif
 
diff --git a/drivers/staging/unisys/visorchannel/visorchannel_funcs.c b/drivers/staging/unisys/visorchannel/visorchannel_funcs.c
index 62ec9280cb3a..947b23c1e478 100644
--- a/drivers/staging/unisys/visorchannel/visorchannel_funcs.c
+++ b/drivers/staging/unisys/visorchannel/visorchannel_funcs.c
@@ -424,7 +424,7 @@ visorchannel_signalremove(VISORCHANNEL *channel, u32 queue, void *msg)
 	/* For each data field in SIGNAL_QUEUE_HEADER that was modified,
 	 * update host memory.
 	 */
-	MEMORYBARRIER;
+	mb(); /* required for channel synch */
 	if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, Tail)) {
 		ERRDRV("visor_memregion_write of Tail failed: (status=%d)\n",
 		       rc);
@@ -477,7 +477,7 @@ visorchannel_signalinsert(VISORCHANNEL *channel, u32 queue, void *msg)
 	/* For each data field in SIGNAL_QUEUE_HEADER that was modified,
 	 * update host memory.
 	 */
-	MEMORYBARRIER;
+	mb(); /* required for channel synch */
 	if (!SIG_WRITE_FIELD(channel, queue, &sig_hdr, Head)) {
 		ERRDRV("visor_memregion_write of Head failed: (status=%d)\n",
 		       rc);