Staging: hv: make gVmbusConnection.ChannelLock a real spinlock

Don't use the wrapper functions for this lock, make it a real
lock so that we know what is going on.

I don't think we really want to be doing a irqsave for this code, but I
left it alone to preserve the original codepath.  It should be reviewed
later.

Cc: Hank Janssen <hjanssen@microsoft.com>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/Channel.c

@@ -686,6 +686,7 @@ VmbusChannelClose(
 	int ret=0;
 	VMBUS_CHANNEL_CLOSE_CHANNEL* msg;
 	VMBUS_CHANNEL_MSGINFO* info;
+	unsigned long flags;
 
 	DPRINT_ENTER(VMBUS);
 
@@ -729,9 +730,9 @@ VmbusChannelClose(
 	// since the caller will free the channel
 	if (Channel->State == CHANNEL_OPEN_STATE)
 	{
-		SpinlockAcquire(gVmbusConnection.ChannelLock);
+		spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 		REMOVE_ENTRY_LIST(&Channel->ListEntry);
-		SpinlockRelease(gVmbusConnection.ChannelLock);
+		spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 
 		FreeVmbusChannel(Channel);
 	}

drivers/staging/hv/ChannelMgmt.c

@@ -233,11 +233,12 @@ VmbusChannelProcessOffer(
 	LIST_ENTRY* curr;
 	bool fNew = true;
 	VMBUS_CHANNEL* channel;
+	unsigned long flags;
 
 	DPRINT_ENTER(VMBUS);
 
 	// Make sure this is a new offer
-	SpinlockAcquire(gVmbusConnection.ChannelLock);
+	spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 
 	ITERATE_LIST_ENTRIES(anchor, curr, &gVmbusConnection.ChannelList)
 	{
@@ -255,7 +256,7 @@ VmbusChannelProcessOffer(
 	{
 		INSERT_TAIL_LIST(&gVmbusConnection.ChannelList, &newChannel->ListEntry);
 	}
-	SpinlockRelease(gVmbusConnection.ChannelLock);
+	spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 
 	if (!fNew)
 	{
@@ -282,9 +283,9 @@ VmbusChannelProcessOffer(
 		DPRINT_ERR(VMBUS, "unable to add child device object (relid %d)",
 			newChannel->OfferMsg.ChildRelId);
 
-		SpinlockAcquire(gVmbusConnection.ChannelLock);
+		spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 		REMOVE_ENTRY_LIST(&newChannel->ListEntry);
-		SpinlockRelease(gVmbusConnection.ChannelLock);
+		spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 
 		FreeVmbusChannel(newChannel);
 	}
@@ -785,8 +786,9 @@ VmbusChannelReleaseUnattachedChannels(
 	LIST_ENTRY *entry;
 	VMBUS_CHANNEL *channel;
 	VMBUS_CHANNEL *start=NULL;
+	unsigned long flags;
 
-	SpinlockAcquire(gVmbusConnection.ChannelLock);
+	spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 
 	while (!IsListEmpty(&gVmbusConnection.ChannelList))
 	{
@@ -813,7 +815,7 @@ VmbusChannelReleaseUnattachedChannels(
 		}
 	}
 
-	SpinlockRelease(gVmbusConnection.ChannelLock);
+	spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 }
 
 // eof

drivers/staging/hv/Connection.c

@@ -69,7 +69,7 @@ VmbusConnect(
 	spin_lock_init(&gVmbusConnection.channelmsg_lock);
 
 	INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelList);
-	gVmbusConnection.ChannelLock = SpinlockCreate();
+	spin_lock_init(&gVmbusConnection.channel_lock);
 
 	// Setup the vmbus event connection for channel interrupt abstraction stuff
 	gVmbusConnection.InterruptPage = PageAlloc(1);
@@ -156,7 +156,6 @@ Cleanup:
 	gVmbusConnection.ConnectState = Disconnected;
 
 	WorkQueueClose(gVmbusConnection.WorkQueue);
-	SpinlockClose(gVmbusConnection.ChannelLock);
 
 	if (gVmbusConnection.InterruptPage)
 	{
@@ -258,8 +257,9 @@ GetChannelFromRelId(
 	VMBUS_CHANNEL* foundChannel=NULL;
 	LIST_ENTRY* anchor;
 	LIST_ENTRY* curr;
+	unsigned long flags;
 
-	SpinlockAcquire(gVmbusConnection.ChannelLock);
+	spin_lock_irqsave(&gVmbusConnection.channel_lock, flags);
 	ITERATE_LIST_ENTRIES(anchor, curr, &gVmbusConnection.ChannelList)
 	{
 		channel = CONTAINING_RECORD(curr, VMBUS_CHANNEL, ListEntry);
@@ -270,7 +270,7 @@ GetChannelFromRelId(
 			break;
 		}
 	}
-	SpinlockRelease(gVmbusConnection.ChannelLock);
+	spin_unlock_irqrestore(&gVmbusConnection.channel_lock, flags);
 
 	return foundChannel;
 }

drivers/staging/hv/VmbusPrivate.h

@@ -84,7 +84,7 @@ typedef struct _VMBUS_CONNECTION {
 
 	// List of channels
 	LIST_ENTRY							ChannelList;
-	HANDLE								ChannelLock;
+	spinlock_t channel_lock;
 
 	HANDLE								WorkQueue;
 } VMBUS_CONNECTION;