Staging: hv: add the Hyper-V virtual bus

This is the virtual bus that all of the Linux Hyper-V drivers use.
Signed-off-by: NHank Janssen <hjanssen@microsoft.com>
Signed-off-by: NHaiyang Zhang <haiyangz@microsoft.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/hv/Channel.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef _CHANNEL_H_
+#define _CHANNEL_H_
+
+#include "osd.h"
+#include "ChannelMgmt.h"
+
+#pragma pack(push,1)
+
+
+// The format must be the same as VMDATA_GPA_DIRECT
+typedef struct _VMBUS_CHANNEL_PACKET_PAGE_BUFFER {
+    UINT16				Type;
+    UINT16				DataOffset8;
+    UINT16				Length8;
+    UINT16				Flags;
+    UINT64				TransactionId;
+	UINT32				Reserved;
+	UINT32				RangeCount;
+    PAGE_BUFFER			Range[MAX_PAGE_BUFFER_COUNT];
+} VMBUS_CHANNEL_PACKET_PAGE_BUFFER;
+
+
+// The format must be the same as VMDATA_GPA_DIRECT
+typedef struct _VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER {
+    UINT16				Type;
+    UINT16				DataOffset8;
+    UINT16				Length8;
+    UINT16				Flags;
+    UINT64				TransactionId;
+	UINT32				Reserved;
+	UINT32				RangeCount;		// Always 1 in this case
+	MULTIPAGE_BUFFER	Range;
+} VMBUS_CHANNEL_PACKET_MULITPAGE_BUFFER;
+
+#pragma pack(pop)
+
+//
+// Routines
+//
+
+INTERNAL int
+VmbusChannelOpen(
+	VMBUS_CHANNEL			*Channel,
+	UINT32					SendRingBufferSize,
+	UINT32					RecvRingBufferSize,
+	PVOID					UserData,
+	UINT32					UserDataLen,
+	PFN_CHANNEL_CALLBACK	pfnOnChannelCallback,
+	PVOID					Context
+	);
+
+INTERNAL void
+VmbusChannelClose(
+	VMBUS_CHANNEL		*Channel
+	);
+
+INTERNAL int
+VmbusChannelSendPacket(
+	VMBUS_CHANNEL		*Channel,
+	const PVOID			Buffer,
+	UINT32				BufferLen,
+	UINT64				RequestId,
+	VMBUS_PACKET_TYPE	Type,
+	UINT32				Flags
+);
+
+INTERNAL int
+VmbusChannelSendPacketPageBuffer(
+	VMBUS_CHANNEL		*Channel,
+	PAGE_BUFFER			PageBuffers[],
+	UINT32				PageCount,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT64				RequestId
+	);
+
+INTERNAL int
+VmbusChannelSendPacketMultiPageBuffer(
+	VMBUS_CHANNEL		*Channel,
+	MULTIPAGE_BUFFER	*MultiPageBuffer,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT64				RequestId
+);
+
+INTERNAL int
+VmbusChannelEstablishGpadl(
+	VMBUS_CHANNEL		*Channel,
+	PVOID				Kbuffer,	// from kmalloc()
+	UINT32				Size,		// page-size multiple
+	UINT32				*GpadlHandle
+	);
+
+INTERNAL int
+VmbusChannelTeardownGpadl(
+	VMBUS_CHANNEL	*Channel,
+	UINT32			GpadlHandle
+	);
+
+INTERNAL int
+VmbusChannelRecvPacket(
+	VMBUS_CHANNEL		*Channel,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32*				BufferActualLen,
+	UINT64*				RequestId
+	);
+
+INTERNAL int
+VmbusChannelRecvPacketRaw(
+	VMBUS_CHANNEL		*Channel,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32*				BufferActualLen,
+	UINT64*				RequestId
+	);
+
+INTERNAL void
+VmbusChannelOnChannelEvent(
+	VMBUS_CHANNEL		*Channel
+	);
+
+INTERNAL void
+VmbusChannelGetDebugInfo(
+	VMBUS_CHANNEL				*Channel,
+	VMBUS_CHANNEL_DEBUG_INFO	*DebugInfo
+	);
+
+INTERNAL void
+VmbusChannelOnTimer(
+	void		*Context
+	);
+#endif //_CHANNEL_H_

drivers/staging/hv/ChannelInterface.c

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+#include "VmbusPrivate.h"
+
+INTERNAL int
+IVmbusChannelOpen(
+	PDEVICE_OBJECT		Device,
+	UINT32				SendBufferSize,
+	UINT32				RecvRingBufferSize,
+	PVOID				UserData,
+	UINT32				UserDataLen,
+	VMBUS_CHANNEL_CALLBACK ChannelCallback,
+	PVOID				Context
+	)
+{
+	return VmbusChannelOpen( (VMBUS_CHANNEL*)Device->context,
+								SendBufferSize,
+								RecvRingBufferSize,
+								UserData,
+								UserDataLen,
+								ChannelCallback,
+								Context);
+}
+
+
+INTERNAL void
+IVmbusChannelClose(
+	PDEVICE_OBJECT		Device
+	)
+{
+	VmbusChannelClose((VMBUS_CHANNEL*)Device->context);
+}
+
+
+INTERNAL int
+IVmbusChannelSendPacket(
+	PDEVICE_OBJECT		Device,
+	const PVOID			Buffer,
+	UINT32				BufferLen,
+	UINT64				RequestId,
+	UINT32				Type,
+	UINT32				Flags
+	)
+{
+	return VmbusChannelSendPacket((VMBUS_CHANNEL*)Device->context,
+									Buffer,
+									BufferLen,
+									RequestId,
+									Type,
+									Flags);
+}
+
+INTERNAL int
+IVmbusChannelSendPacketPageBuffer(
+	PDEVICE_OBJECT		Device,
+	PAGE_BUFFER			PageBuffers[],
+	UINT32				PageCount,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT64				RequestId
+	)
+{
+	return VmbusChannelSendPacketPageBuffer((VMBUS_CHANNEL*)Device->context,
+												PageBuffers,
+												PageCount,
+												Buffer,
+												BufferLen,
+												RequestId);
+}
+
+INTERNAL int
+IVmbusChannelSendPacketMultiPageBuffer(
+	PDEVICE_OBJECT		Device,
+	MULTIPAGE_BUFFER	*MultiPageBuffer,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT64				RequestId
+	)
+{
+	return VmbusChannelSendPacketMultiPageBuffer((VMBUS_CHANNEL*)Device->context,
+													MultiPageBuffer,
+													Buffer,
+													BufferLen,
+													RequestId);
+}
+
+INTERNAL int
+IVmbusChannelRecvPacket (
+	PDEVICE_OBJECT		Device,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32*				BufferActualLen,
+	UINT64*				RequestId
+	)
+{
+	return VmbusChannelRecvPacket((VMBUS_CHANNEL*)Device->context,
+									Buffer,
+									BufferLen,
+									BufferActualLen,
+									RequestId);
+}
+
+INTERNAL int
+IVmbusChannelRecvPacketRaw(
+	PDEVICE_OBJECT		Device,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32*				BufferActualLen,
+	UINT64*				RequestId
+	)
+{
+	return VmbusChannelRecvPacketRaw((VMBUS_CHANNEL*)Device->context,
+										Buffer,
+										BufferLen,
+										BufferActualLen,
+										RequestId);
+}
+
+INTERNAL int
+IVmbusChannelEstablishGpadl(
+	PDEVICE_OBJECT		Device,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32*				GpadlHandle
+	)
+{
+	return VmbusChannelEstablishGpadl((VMBUS_CHANNEL*)Device->context,
+										Buffer,
+										BufferLen,
+										GpadlHandle);
+}
+
+INTERNAL int
+IVmbusChannelTeardownGpadl(
+   PDEVICE_OBJECT		Device,
+   UINT32				GpadlHandle
+	)
+{
+	return VmbusChannelTeardownGpadl((VMBUS_CHANNEL*)Device->context,
+										GpadlHandle);
+
+}
+
+INTERNAL void
+GetChannelInterface(
+	VMBUS_CHANNEL_INTERFACE *ChannelInterface
+	)
+{
+	ChannelInterface->Open						= IVmbusChannelOpen;
+	ChannelInterface->Close						= IVmbusChannelClose;
+	ChannelInterface->SendPacket				= IVmbusChannelSendPacket;
+	ChannelInterface->SendPacketPageBuffer		= IVmbusChannelSendPacketPageBuffer;
+	ChannelInterface->SendPacketMultiPageBuffer = IVmbusChannelSendPacketMultiPageBuffer;
+	ChannelInterface->RecvPacket				= IVmbusChannelRecvPacket;
+	ChannelInterface->RecvPacketRaw				= IVmbusChannelRecvPacketRaw;
+	ChannelInterface->EstablishGpadl			= IVmbusChannelEstablishGpadl;
+	ChannelInterface->TeardownGpadl				= IVmbusChannelTeardownGpadl;
+	ChannelInterface->GetInfo					= GetChannelInfo;
+}
+
+
+INTERNAL void
+GetChannelInfo(
+	PDEVICE_OBJECT		Device,
+	DEVICE_INFO			*DeviceInfo
+			   )
+{
+	VMBUS_CHANNEL_DEBUG_INFO debugInfo;
+
+	if (Device->context)
+	{
+		VmbusChannelGetDebugInfo((VMBUS_CHANNEL*)Device->context, &debugInfo);
+
+		DeviceInfo->ChannelId = debugInfo.RelId;
+		DeviceInfo->ChannelState = debugInfo.State;
+		memcpy(&DeviceInfo->ChannelType, &debugInfo.InterfaceType, sizeof(GUID));
+		memcpy(&DeviceInfo->ChannelInstance, &debugInfo.InterfaceInstance, sizeof(GUID));
+
+		DeviceInfo->MonitorId = debugInfo.MonitorId;
+
+		DeviceInfo->ServerMonitorPending = debugInfo.ServerMonitorPending;
+		DeviceInfo->ServerMonitorLatency = debugInfo.ServerMonitorLatency;
+		DeviceInfo->ServerMonitorConnectionId = debugInfo.ServerMonitorConnectionId;
+
+		DeviceInfo->ClientMonitorPending = debugInfo.ClientMonitorPending;
+		DeviceInfo->ClientMonitorLatency = debugInfo.ClientMonitorLatency;
+		DeviceInfo->ClientMonitorConnectionId = debugInfo.ClientMonitorConnectionId;
+
+		DeviceInfo->Inbound.InterruptMask = debugInfo.Inbound.CurrentInterruptMask;
+		DeviceInfo->Inbound.ReadIndex = debugInfo.Inbound.CurrentReadIndex;
+		DeviceInfo->Inbound.WriteIndex = debugInfo.Inbound.CurrentWriteIndex;
+		DeviceInfo->Inbound.BytesAvailToRead = debugInfo.Inbound.BytesAvailToRead;
+		DeviceInfo->Inbound.BytesAvailToWrite = debugInfo.Inbound.BytesAvailToWrite;
+
+		DeviceInfo->Outbound.InterruptMask = debugInfo.Outbound.CurrentInterruptMask;
+		DeviceInfo->Outbound.ReadIndex = debugInfo.Outbound.CurrentReadIndex;
+		DeviceInfo->Outbound.WriteIndex = debugInfo.Outbound.CurrentWriteIndex;
+		DeviceInfo->Outbound.BytesAvailToRead = debugInfo.Outbound.BytesAvailToRead;
+		DeviceInfo->Outbound.BytesAvailToWrite = debugInfo.Outbound.BytesAvailToWrite;
+	}
+}

drivers/staging/hv/ChannelInterface.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef _CHANNEL_INTERFACE_H_
+#define _CHANNEL_INTERFACE_H_
+
+#include "VmbusApi.h"
+
+INTERNAL void
+GetChannelInterface(
+	VMBUS_CHANNEL_INTERFACE *ChannelInterface
+	);
+
+INTERNAL void
+GetChannelInfo(
+	PDEVICE_OBJECT		Device,
+	DEVICE_INFO			*DeviceInfo
+	);
+
+#endif // _CHANNEL_INTERFACE_H_

drivers/staging/hv/ChannelMgmt.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef _CHANNEL_MGMT_H_
+#define _CHANNEL_MGMT_H_
+
+#include "osd.h"
+#include "List.h"
+#include "RingBuffer.h"
+
+#include "VmbusChannelInterface.h"
+#include "ChannelMessages.h"
+
+
+
+typedef void (*PFN_CHANNEL_CALLBACK)(PVOID context);
+
+typedef enum {
+	CHANNEL_OFFER_STATE,
+	CHANNEL_OPENING_STATE,
+	CHANNEL_OPEN_STATE,
+} VMBUS_CHANNEL_STATE;
+
+typedef struct _VMBUS_CHANNEL {
+	LIST_ENTRY					ListEntry;
+
+	DEVICE_OBJECT*				DeviceObject;
+
+	HANDLE						PollTimer; // SA-111 workaround
+
+	VMBUS_CHANNEL_STATE			State;
+
+	VMBUS_CHANNEL_OFFER_CHANNEL OfferMsg;
+	// These are based on the OfferMsg.MonitorId. Save it here for easy access.
+	UINT8						MonitorGroup;
+	UINT8						MonitorBit;
+
+	UINT32						RingBufferGpadlHandle;
+
+	// Allocated memory for ring buffer
+	VOID*						RingBufferPages;
+	UINT32						RingBufferPageCount;
+	RING_BUFFER_INFO			Outbound;	// send to parent
+	RING_BUFFER_INFO			Inbound;	// receive from parent
+	HANDLE						InboundLock;
+	HANDLE						ControlWQ;
+
+	// Channel callback are invoked in this workqueue context
+	//HANDLE						dataWorkQueue;
+
+	PFN_CHANNEL_CALLBACK		OnChannelCallback;
+	PVOID						ChannelCallbackContext;
+
+} VMBUS_CHANNEL;
+
+
+typedef struct _VMBUS_CHANNEL_DEBUG_INFO {
+	UINT32						RelId;
+	VMBUS_CHANNEL_STATE			State;
+	GUID						InterfaceType;
+    GUID						InterfaceInstance;
+	UINT32						MonitorId;
+	UINT32						ServerMonitorPending;
+	UINT32						ServerMonitorLatency;
+	UINT32						ServerMonitorConnectionId;
+	UINT32						ClientMonitorPending;
+	UINT32						ClientMonitorLatency;
+	UINT32						ClientMonitorConnectionId;
+
+	RING_BUFFER_DEBUG_INFO		Inbound;
+	RING_BUFFER_DEBUG_INFO		Outbound;
+} VMBUS_CHANNEL_DEBUG_INFO;
+
+
+typedef union {
+	VMBUS_CHANNEL_VERSION_SUPPORTED		VersionSupported;
+	VMBUS_CHANNEL_OPEN_RESULT			OpenResult;
+	VMBUS_CHANNEL_GPADL_TORNDOWN		GpadlTorndown;
+	VMBUS_CHANNEL_GPADL_CREATED			GpadlCreated;
+	VMBUS_CHANNEL_VERSION_RESPONSE		VersionResponse;
+} VMBUS_CHANNEL_MESSAGE_RESPONSE;
+
+
+// Represents each channel msg on the vmbus connection
+// This is a variable-size data structure depending on
+// the msg type itself
+typedef struct _VMBUS_CHANNEL_MSGINFO {
+	// Bookkeeping stuff
+	LIST_ENTRY		MsgListEntry;
+
+	// So far, this is only used to handle gpadl body message
+	LIST_ENTRY		SubMsgList;
+
+	// Synchronize the request/response if needed
+	HANDLE			WaitEvent;
+
+	VMBUS_CHANNEL_MESSAGE_RESPONSE Response;
+
+	UINT32			MessageSize;
+	// The channel message that goes out on the "wire".
+	// It will contain at minimum the VMBUS_CHANNEL_MESSAGE_HEADER header
+	unsigned char	Msg[0];
+} VMBUS_CHANNEL_MSGINFO;
+
+
+//
+// Routines
+//
+
+INTERNAL VMBUS_CHANNEL*
+AllocVmbusChannel(
+	void
+	);
+
+INTERNAL void
+FreeVmbusChannel(
+	VMBUS_CHANNEL *Channel
+	);
+
+INTERNAL void
+VmbusOnChannelMessage(
+	void *Context
+	);
+
+INTERNAL int
+VmbusChannelRequestOffers(
+	void
+	);
+
+INTERNAL void
+VmbusChannelReleaseUnattachedChannels(
+	void
+	);
+
+#endif //_CHANNEL_MGMT_H_

drivers/staging/hv/Connection.c

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#include "logging.h"
+
+#include "VmbusPrivate.h"
+
+//
+// Globals
+//
+
+
+VMBUS_CONNECTION gVmbusConnection = {
+	.ConnectState		= Disconnected,
+	.NextGpadlHandle	= 0xE1E10,
+};
+
+
+/*++
+
+Name:
+	VmbusConnect()
+
+Description:
+	Sends a connect request on the partition service connection
+
+--*/
+int
+VmbusConnect(
+	)
+{
+	int ret=0;
+	VMBUS_CHANNEL_MSGINFO *msgInfo=NULL;
+	VMBUS_CHANNEL_INITIATE_CONTACT *msg;
+
+	DPRINT_ENTER(VMBUS);
+
+	// Make sure we are not connecting or connected
+	if (gVmbusConnection.ConnectState != Disconnected)
+		return -1;
+
+	// Initialize the vmbus connection
+	gVmbusConnection.ConnectState = Connecting;
+	gVmbusConnection.WorkQueue = WorkQueueCreate("vmbusQ");
+
+	INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelMsgList);
+	gVmbusConnection.ChannelMsgLock = SpinlockCreate();
+
+	INITIALIZE_LIST_HEAD(&gVmbusConnection.ChannelList);
+	gVmbusConnection.ChannelLock = SpinlockCreate();
+
+	// Setup the vmbus event connection for channel interrupt abstraction stuff
+	gVmbusConnection.InterruptPage = PageAlloc(1);
+	if (gVmbusConnection.InterruptPage == NULL)
+	{
+		ret = -1;
+		goto Cleanup;
+	}
+
+	gVmbusConnection.RecvInterruptPage = gVmbusConnection.InterruptPage;
+	gVmbusConnection.SendInterruptPage = (void*)((ULONG_PTR)gVmbusConnection.InterruptPage + (PAGE_SIZE >> 1));
+
+	// Setup the monitor notification facility. The 1st page for parent->child and the 2nd page for child->parent
+	gVmbusConnection.MonitorPages = PageAlloc(2);
+	if (gVmbusConnection.MonitorPages == NULL)
+	{
+		ret = -1;
+		goto Cleanup;
+	}
+
+	msgInfo = (VMBUS_CHANNEL_MSGINFO*)MemAllocZeroed(sizeof(VMBUS_CHANNEL_MSGINFO) + sizeof(VMBUS_CHANNEL_INITIATE_CONTACT));
+	if (msgInfo == NULL)
+	{
+		ret = -1;
+		goto Cleanup;
+	}
+
+	msgInfo->WaitEvent = WaitEventCreate();
+	msg = (VMBUS_CHANNEL_INITIATE_CONTACT*)msgInfo->Msg;
+
+	msg->Header.MessageType = ChannelMessageInitiateContact;
+	msg->VMBusVersionRequested = VMBUS_REVISION_NUMBER;
+	msg->InterruptPage = GetPhysicalAddress(gVmbusConnection.InterruptPage);
+	msg->MonitorPage1 = GetPhysicalAddress(gVmbusConnection.MonitorPages);
+	msg->MonitorPage2 = GetPhysicalAddress((PVOID)((ULONG_PTR)gVmbusConnection.MonitorPages + PAGE_SIZE));
+
+	// Add to list before we send the request since we may receive the response
+	// before returning from this routine
+	SpinlockAcquire(gVmbusConnection.ChannelMsgLock);
+	INSERT_TAIL_LIST(&gVmbusConnection.ChannelMsgList, &msgInfo->MsgListEntry);
+	SpinlockRelease(gVmbusConnection.ChannelMsgLock);
+
+	DPRINT_DBG(VMBUS, "Vmbus connection -  interrupt pfn %llx, monitor1 pfn %llx,, monitor2 pfn %llx",
+		msg->InterruptPage, msg->MonitorPage1, msg->MonitorPage2);
+
+	DPRINT_DBG(VMBUS, "Sending channel initiate msg...");
+
+	ret = VmbusPostMessage(msg, sizeof(VMBUS_CHANNEL_INITIATE_CONTACT));
+	if (ret != 0)
+	{
+		REMOVE_ENTRY_LIST(&msgInfo->MsgListEntry);
+		goto Cleanup;
+	}
+
+	// Wait for the connection response
+	WaitEventWait(msgInfo->WaitEvent);
+
+	REMOVE_ENTRY_LIST(&msgInfo->MsgListEntry);
+
+	// Check if successful
+	if (msgInfo->Response.VersionResponse.VersionSupported)
+	{
+		DPRINT_INFO(VMBUS, "Vmbus connected!!");
+		gVmbusConnection.ConnectState = Connected;
+
+	}
+	else
+	{
+		DPRINT_ERR(VMBUS, "Vmbus connection failed!!...current version (%d) not supported", VMBUS_REVISION_NUMBER);
+		ret = -1;
+
+		goto Cleanup;
+	}
+
+
+	WaitEventClose(msgInfo->WaitEvent);
+	MemFree(msgInfo);
+	DPRINT_EXIT(VMBUS);
+
+	return 0;
+
+Cleanup:
+
+	gVmbusConnection.ConnectState = Disconnected;
+
+	WorkQueueClose(gVmbusConnection.WorkQueue);
+	SpinlockClose(gVmbusConnection.ChannelLock);
+	SpinlockClose(gVmbusConnection.ChannelMsgLock);
+
+	if (gVmbusConnection.InterruptPage)
+	{
+		PageFree(gVmbusConnection.InterruptPage, 1);
+		gVmbusConnection.InterruptPage = NULL;
+	}
+
+	if (gVmbusConnection.MonitorPages)
+	{
+		PageFree(gVmbusConnection.MonitorPages, 2);
+		gVmbusConnection.MonitorPages = NULL;
+	}
+
+	if (msgInfo)
+	{
+		if (msgInfo->WaitEvent)
+			WaitEventClose(msgInfo->WaitEvent);
+
+		MemFree(msgInfo);
+	}
+
+	DPRINT_EXIT(VMBUS);
+
+	return ret;
+}
+
+
+/*++
+
+Name:
+	VmbusDisconnect()
+
+Description:
+	Sends a disconnect request on the partition service connection
+
+--*/
+int
+VmbusDisconnect(
+	VOID
+	)
+{
+	int ret=0;
+	VMBUS_CHANNEL_UNLOAD *msg;
+
+	DPRINT_ENTER(VMBUS);
+
+	// Make sure we are connected
+	if (gVmbusConnection.ConnectState != Connected)
+		return -1;
+
+	msg = MemAllocZeroed(sizeof(VMBUS_CHANNEL_UNLOAD));
+
+	msg->MessageType = ChannelMessageUnload;
+
+	ret = VmbusPostMessage(msg, sizeof(VMBUS_CHANNEL_UNLOAD));
+
+	if (ret != 0)
+	{
+		goto Cleanup;
+	}
+
+	PageFree(gVmbusConnection.InterruptPage, 1);
+
+	// TODO: iterate thru the msg list and free up
+
+	SpinlockClose(gVmbusConnection.ChannelMsgLock);
+
+	WorkQueueClose(gVmbusConnection.WorkQueue);
+
+	gVmbusConnection.ConnectState = Disconnected;
+
+	DPRINT_INFO(VMBUS, "Vmbus disconnected!!");
+
+Cleanup:
+	if (msg)
+	{
+		MemFree(msg);
+	}
+
+	DPRINT_EXIT(VMBUS);
+
+	return ret;
+}
+
+
+/*++
+
+Name:
+	GetChannelFromRelId()
+
+Description:
+	Get the channel object given its child relative id (ie channel id)
+
+--*/
+VMBUS_CHANNEL*
+GetChannelFromRelId(
+	UINT32 relId
+	)
+{
+	VMBUS_CHANNEL* channel;
+	VMBUS_CHANNEL* foundChannel=NULL;
+	LIST_ENTRY* anchor;
+	LIST_ENTRY* curr;
+
+	SpinlockAcquire(gVmbusConnection.ChannelLock);
+	ITERATE_LIST_ENTRIES(anchor, curr, &gVmbusConnection.ChannelList)
+	{
+		channel = CONTAINING_RECORD(curr, VMBUS_CHANNEL, ListEntry);
+
+		if (channel->OfferMsg.ChildRelId == relId)
+		{
+			foundChannel = channel;
+			break;
+		}
+	}
+	SpinlockRelease(gVmbusConnection.ChannelLock);
+
+	return foundChannel;
+}
+
+
+
+/*++
+
+Name:
+	VmbusProcessChannelEvent()
+
+Description:
+	Process a channel event notification
+
+--*/
+static void
+VmbusProcessChannelEvent(
+	PVOID context
+	)
+{
+	VMBUS_CHANNEL* channel;
+	UINT32 relId = (UINT32)(ULONG_PTR)context;
+
+	ASSERT(relId > 0);
+
+	// Find the channel based on this relid and invokes
+	// the channel callback to process the event
+	channel = GetChannelFromRelId(relId);
+
+	if (channel)
+	{
+		VmbusChannelOnChannelEvent(channel);
+		//WorkQueueQueueWorkItem(channel->dataWorkQueue, VmbusChannelOnChannelEvent, (void*)channel);
+	}
+	else
+	{
+        DPRINT_ERR(VMBUS, "channel not found for relid - %d.", relId);
+	}
+}
+
+
+/*++
+
+Name:
+	VmbusOnEvents()
+
+Description:
+	Handler for events
+
+--*/
+VOID
+VmbusOnEvents(
+  VOID
+	)
+{
+	int dword;
+	//int maxdword = PAGE_SIZE >> 3; // receive size is 1/2 page and divide that by 4 bytes
+	int maxdword = MAX_NUM_CHANNELS_SUPPORTED >> 5;
+	int bit;
+	int relid;
+	UINT32* recvInterruptPage = gVmbusConnection.RecvInterruptPage;
+	//VMBUS_CHANNEL_MESSAGE* receiveMsg;
+
+	DPRINT_ENTER(VMBUS);
+
+	// Check events
+	if (recvInterruptPage)
+	{
+		for (dword = 0; dword < maxdword; dword++)
+		{
+			if (recvInterruptPage[dword])
+			{
+				for (bit = 0; bit < 32; bit++)
+				{
+					if (BitTestAndClear(&recvInterruptPage[dword], bit))
+					{
+						relid = (dword << 5) + bit;
+
+						DPRINT_DBG(VMBUS, "event detected for relid - %d", relid);
+
+						if (relid == 0) // special case - vmbus channel protocol msg
+						{
+							DPRINT_DBG(VMBUS, "invalid relid - %d", relid);
+
+							continue;						}
+						else
+						{
+							//QueueWorkItem(VmbusProcessEvent, (void*)relid);
+							//ret = WorkQueueQueueWorkItem(gVmbusConnection.workQueue, VmbusProcessChannelEvent, (void*)relid);
+							VmbusProcessChannelEvent((void*)(ULONG_PTR)relid);
+						}
+					}
+				}
+			}
+		 }
+	}
+	DPRINT_EXIT(VMBUS);
+
+	return;
+}
+
+/*++
+
+Name:
+	VmbusPostMessage()
+
+Description:
+	Send a msg on the vmbus's message connection
+
+--*/
+int
+VmbusPostMessage(
+	PVOID			buffer,
+	SIZE_T			bufferLen
+	)
+{
+	int ret=0;
+	HV_CONNECTION_ID connId;
+
+
+	connId.AsUINT32 =0;
+	connId.u.Id = VMBUS_MESSAGE_CONNECTION_ID;
+	ret = HvPostMessage(
+			connId,
+			1,
+			buffer,
+			bufferLen);
+
+	return  ret;
+}
+
+/*++
+
+Name:
+	VmbusSetEvent()
+
+Description:
+	Send an event notification to the parent
+
+--*/
+int
+VmbusSetEvent(UINT32 childRelId)
+{
+	int ret=0;
+
+	DPRINT_ENTER(VMBUS);
+
+	// Each UINT32 represents 32 channels
+	BitSet((UINT32*)gVmbusConnection.SendInterruptPage + (childRelId >> 5), childRelId & 31);
+	ret = HvSignalEvent();
+
+	DPRINT_EXIT(VMBUS);
+
+	return ret;
+}
+
+// EOF

drivers/staging/hv/Hv.c

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#include "logging.h"
+#include "VmbusPrivate.h"
+
+//
+// Globals
+//
+
+// The one and only
+HV_CONTEXT gHvContext={
+	.SynICInitialized = FALSE,
+	.HypercallPage = NULL,
+	.SignalEventParam = NULL,
+	.SignalEventBuffer = NULL,
+};
+
+
+/*++
+
+Name:
+	HvQueryHypervisorPresence()
+
+Description:
+	Query the cpuid for presense of windows hypervisor
+
+--*/
+static int
+HvQueryHypervisorPresence (
+    void
+    )
+{
+    unsigned int eax;
+    unsigned int ebx;
+    unsigned int ecx;
+    unsigned int edx;
+    unsigned int op;
+
+    eax = 0;
+    ebx = 0;
+    ecx = 0;
+    edx = 0;
+    op = HvCpuIdFunctionVersionAndFeatures;
+    do_cpuid(op, &eax, &ebx, &ecx, &edx);
+
+	return (ecx & HV_PRESENT_BIT);
+}
+
+
+/*++
+
+Name:
+	HvQueryHypervisorInfo()
+
+Description:
+	Get version info of the windows hypervisor
+
+--*/
+static int
+HvQueryHypervisorInfo (
+    void
+    )
+{
+    unsigned int eax;
+    unsigned int ebx;
+    unsigned int ecx;
+    unsigned int edx;
+    unsigned int maxLeaf;
+    unsigned int op;
+
+    //
+    // Its assumed that this is called after confirming that Viridian is present.
+    // Query id and revision.
+    //
+
+    eax = 0;
+    ebx = 0;
+    ecx = 0;
+    edx = 0;
+    op = HvCpuIdFunctionHvVendorAndMaxFunction;
+    do_cpuid(op, &eax, &ebx, &ecx, &edx);
+
+    DPRINT_INFO(VMBUS, "Vendor ID: %c%c%c%c%c%c%c%c%c%c%c%c",
+           (ebx & 0xFF),
+           ((ebx >> 8) & 0xFF),
+           ((ebx >> 16) & 0xFF),
+           ((ebx >> 24) & 0xFF),
+           (ecx & 0xFF),
+           ((ecx >> 8) & 0xFF),
+           ((ecx >> 16) & 0xFF),
+           ((ecx >> 24) & 0xFF),
+           (edx & 0xFF),
+           ((edx >> 8) & 0xFF),
+           ((edx >> 16) & 0xFF),
+           ((edx >> 24) & 0xFF));
+
+    maxLeaf = eax;
+    eax = 0;
+    ebx = 0;
+    ecx = 0;
+    edx = 0;
+    op = HvCpuIdFunctionHvInterface;
+    do_cpuid(op, &eax, &ebx, &ecx, &edx);
+
+    DPRINT_INFO(VMBUS, "Interface ID: %c%c%c%c",
+           (eax & 0xFF),
+           ((eax >> 8) & 0xFF),
+           ((eax >> 16) & 0xFF),
+           ((eax >> 24) & 0xFF));
+
+	 if (maxLeaf >= HvCpuIdFunctionMsHvVersion) {
+        eax = 0;
+        ebx = 0;
+        ecx = 0;
+        edx = 0;
+        op = HvCpuIdFunctionMsHvVersion;
+        do_cpuid(op, &eax, &ebx, &ecx, &edx);
+        DPRINT_INFO(VMBUS, "OS Build:%d-%d.%d-%d-%d.%d",
+               eax,
+               ebx >> 16,
+               ebx & 0xFFFF,
+               ecx,
+               edx >> 24,
+               edx & 0xFFFFFF);
+    }
+    return maxLeaf;
+}
+
+
+/*++
+
+Name:
+	HvDoHypercall()
+
+Description:
+	Invoke the specified hypercall
+
+--*/
+static UINT64
+HvDoHypercall (
+    UINT64  Control,
+    void*   Input,
+    void*   Output
+    )
+{
+#ifdef x86_64
+    UINT64 hvStatus=0;
+    UINT64 inputAddress = (Input)? GetPhysicalAddress(Input) : 0;
+	UINT64 outputAddress = (Output)? GetPhysicalAddress(Output) : 0;
+    volatile void* hypercallPage = gHvContext.HypercallPage;
+
+    DPRINT_DBG(VMBUS, "Hypercall <control %llx input phys %llx virt %p output phys %llx virt %p hypercall %p>",
+		Control,
+		inputAddress,
+		Input,
+		outputAddress,
+		Output,
+		hypercallPage);
+
+	__asm__ __volatile__ ("mov %0, %%r8" : : "r" (outputAddress):  "r8");
+	__asm__ __volatile__ ("call *%3" : "=a"(hvStatus): "c" (Control), "d" (inputAddress), "m" (hypercallPage));
+
+    DPRINT_DBG(VMBUS, "Hypercall <return %llx>",  hvStatus);
+
+    return hvStatus;
+
+#else
+
+    UINT32 controlHi = Control >> 32;
+    UINT32 controlLo = Control & 0xFFFFFFFF;
+    UINT32 hvStatusHi = 1;
+    UINT32 hvStatusLo = 1;
+    UINT64 inputAddress = (Input) ? GetPhysicalAddress(Input) : 0;
+    UINT32 inputAddressHi = inputAddress >> 32;
+    UINT32 inputAddressLo = inputAddress & 0xFFFFFFFF;
+	UINT64 outputAddress = (Output) ?GetPhysicalAddress(Output) : 0;
+    UINT32 outputAddressHi = outputAddress >> 32;
+    UINT32 outputAddressLo = outputAddress & 0xFFFFFFFF;
+    volatile void* hypercallPage = gHvContext.HypercallPage;
+
+    DPRINT_DBG(VMBUS, "Hypercall <control %llx input %p output %p>",
+		Control,
+		Input,
+		Output);
+
+	__asm__ __volatile__ ("call *%8" : "=d"(hvStatusHi), "=a"(hvStatusLo) : "d" (controlHi), "a" (controlLo), "b" (inputAddressHi), "c" (inputAddressLo), "D"(outputAddressHi), "S"(outputAddressLo), "m" (hypercallPage));
+
+
+    DPRINT_DBG(VMBUS, "Hypercall <return %llx>",  hvStatusLo | ((UINT64)hvStatusHi << 32));
+
+    return (hvStatusLo | ((UINT64)hvStatusHi << 32));
+#endif // x86_64
+}
+
+/*++
+
+Name:
+	HvInit()
+
+Description:
+	Main initialization routine. This routine must be called
+	before any other routines in here are called
+
+--*/
+static int
+HvInit (
+    void
+    )
+{
+	int ret=0;
+    int maxLeaf;
+	HV_X64_MSR_HYPERCALL_CONTENTS hypercallMsr;
+	void* virtAddr=0;
+	ULONG_PTR physAddr=0;
+
+	DPRINT_ENTER(VMBUS);
+
+	memset(gHvContext.synICEventPage, 0, sizeof(HANDLE)*MAX_NUM_CPUS);
+	memset(gHvContext.synICMessagePage, 0, sizeof(HANDLE)*MAX_NUM_CPUS);
+
+	if (!HvQueryHypervisorPresence())
+	{
+		DPRINT_ERR(VMBUS, "No Windows hypervisor detected!!");
+		goto Cleanup;
+	}
+
+	DPRINT_INFO(VMBUS, "Windows hypervisor detected! Retrieving more info...");
+
+    maxLeaf = HvQueryHypervisorInfo();
+    //HvQueryHypervisorFeatures(maxLeaf);
+
+	// Determine if we are running on xenlinux (ie x2v shim) or native linux
+	gHvContext.GuestId = ReadMsr(HV_X64_MSR_GUEST_OS_ID);
+
+	if (gHvContext.GuestId == 0)
+	{
+		// Write our OS info
+		WriteMsr(HV_X64_MSR_GUEST_OS_ID, HV_LINUX_GUEST_ID);
+
+		gHvContext.GuestId = HV_LINUX_GUEST_ID;
+	}
+
+	// See if the hypercall page is already set
+	hypercallMsr.AsUINT64 = ReadMsr(HV_X64_MSR_HYPERCALL);
+
+	if (gHvContext.GuestId == HV_LINUX_GUEST_ID)
+	{
+		// Allocate the hypercall page memory
+		//virtAddr = PageAlloc(1);
+		virtAddr = VirtualAllocExec(PAGE_SIZE);
+
+		if (!virtAddr)
+		{
+			DPRINT_ERR(VMBUS, "unable to allocate hypercall page!!");
+			goto Cleanup;
+		}
+
+		hypercallMsr.Enable = 1;
+		//hypercallMsr.GuestPhysicalAddress = Logical2PhysicalAddr(virtAddr) >> PAGE_SHIFT;
+		hypercallMsr.GuestPhysicalAddress = Virtual2Physical(virtAddr) >> PAGE_SHIFT;
+		WriteMsr(HV_X64_MSR_HYPERCALL, hypercallMsr.AsUINT64);
+
+        // Confirm that hypercall page did get setup.
+		hypercallMsr.AsUINT64 = 0;
+		hypercallMsr.AsUINT64 = ReadMsr(HV_X64_MSR_HYPERCALL);
+
+		if (!hypercallMsr.Enable)
+		{
+			DPRINT_ERR(VMBUS, "unable to set hypercall page!!");
+			goto Cleanup;
+		}
+
+		gHvContext.HypercallPage = virtAddr;
+	}
+	else
+	{
+		DPRINT_ERR(VMBUS, "Unknown guest id (0x%llx)!!", gHvContext.GuestId);
+		goto Cleanup;
+	}
+
+    DPRINT_INFO(VMBUS, "Hypercall page VA=0x%08x, PA=0x%08x",
+               (unsigned long)gHvContext.HypercallPage,
+               (unsigned long)hypercallMsr.GuestPhysicalAddress << PAGE_SHIFT);
+
+	// Setup the global signal event param for the signal event hypercall
+	gHvContext.SignalEventBuffer = MemAlloc(sizeof(HV_INPUT_SIGNAL_EVENT_BUFFER));
+	if (!gHvContext.SignalEventBuffer)
+	{
+		goto Cleanup;
+	}
+
+	gHvContext.SignalEventParam = (PHV_INPUT_SIGNAL_EVENT)(ALIGN_UP((ULONG_PTR)gHvContext.SignalEventBuffer, HV_HYPERCALL_PARAM_ALIGN));
+	gHvContext.SignalEventParam->ConnectionId.AsUINT32 = 0;
+	gHvContext.SignalEventParam->ConnectionId.u.Id = VMBUS_EVENT_CONNECTION_ID;
+	gHvContext.SignalEventParam->FlagNumber = 0;
+	gHvContext.SignalEventParam->RsvdZ = 0;
+
+    //DPRINT_DBG(VMBUS, "My id %llu", HvGetCurrentPartitionId());
+
+	DPRINT_EXIT(VMBUS);
+
+    return ret;
+
+Cleanup:
+	if (virtAddr)
+	{
+		if (hypercallMsr.Enable)
+		{
+			hypercallMsr.AsUINT64 = 0;
+			WriteMsr(HV_X64_MSR_HYPERCALL, hypercallMsr.AsUINT64);
+		}
+
+		VirtualFree(virtAddr);
+	}
+	ret = -1;
+	DPRINT_EXIT(VMBUS);
+
+	return ret;
+}
+
+
+/*++
+
+Name:
+	HvCleanup()
+
+Description:
+	Cleanup routine. This routine is called normally during driver unloading or exiting.
+
+--*/
+void
+HvCleanup (
+    void
+    )
+{
+	HV_X64_MSR_HYPERCALL_CONTENTS hypercallMsr;
+
+	DPRINT_ENTER(VMBUS);
+
+	if (gHvContext.SignalEventBuffer)
+	{
+		MemFree(gHvContext.SignalEventBuffer);
+		gHvContext.SignalEventBuffer = NULL;
+		gHvContext.SignalEventParam = NULL;
+	}
+
+	if (gHvContext.GuestId == HV_LINUX_GUEST_ID)
+	{
+		if (gHvContext.HypercallPage)
+		{
+			hypercallMsr.AsUINT64 = 0;
+			WriteMsr(HV_X64_MSR_HYPERCALL, hypercallMsr.AsUINT64);
+			VirtualFree(gHvContext.HypercallPage);
+			gHvContext.HypercallPage = NULL;
+		}
+	}
+
+	DPRINT_EXIT(VMBUS);
+
+}
+
+
+/*++
+
+Name:
+	HvPostMessage()
+
+Description:
+	Post a message using the hypervisor message IPC. This
+	involves a hypercall.
+
+--*/
+HV_STATUS
+HvPostMessage(
+	HV_CONNECTION_ID connectionId,
+	HV_MESSAGE_TYPE  messageType,
+	PVOID            payload,
+	SIZE_T           payloadSize
+	)
+{
+	struct alignedInput {
+		UINT64					alignment8;
+		HV_INPUT_POST_MESSAGE	msg;
+	};
+
+	PHV_INPUT_POST_MESSAGE alignedMsg;
+	HV_STATUS status;
+	ULONG_PTR addr;
+
+	if (payloadSize > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
+	{
+		return -1;
+	}
+
+	addr = (ULONG_PTR)MemAllocAtomic(sizeof(struct alignedInput));
+
+	if (!addr)
+	{
+		return -1;
+	}
+
+	alignedMsg = (PHV_INPUT_POST_MESSAGE)(ALIGN_UP(addr, HV_HYPERCALL_PARAM_ALIGN));
+
+	alignedMsg->ConnectionId = connectionId;
+	alignedMsg->MessageType = messageType;
+	alignedMsg->PayloadSize = payloadSize;
+	memcpy((void*)alignedMsg->Payload, payload, payloadSize);
+
+	status = HvDoHypercall(HvCallPostMessage, alignedMsg, 0) & 0xFFFF;
+
+	MemFree((void*)addr);
+
+	return status;
+}
+
+
+/*++
+
+Name:
+	HvSignalEvent()
+
+Description:
+	Signal an event on the specified connection using the hypervisor event IPC. This
+	involves a hypercall.
+
+--*/
+HV_STATUS
+HvSignalEvent(
+	)
+{
+	HV_STATUS status;
+
+	status = HvDoHypercall(HvCallSignalEvent, gHvContext.SignalEventParam, 0) & 0xFFFF;
+
+	return status;
+}
+
+
+/*++
+
+Name:
+	HvSynicInit()
+
+Description:
+	Initialize the Synthethic Interrupt Controller. If it is already initialized by
+	another entity (ie x2v shim), we need to retrieve the initialized message and event pages.
+	Otherwise, we create and initialize the message and event pages.
+
+--*/
+int
+HvSynicInit (
+	UINT32 irqVector
+	)
+{
+	UINT64			version;
+	HV_SYNIC_SIMP	simp;
+	HV_SYNIC_SIEFP	siefp;
+    HV_SYNIC_SINT	sharedSint;
+	HV_SYNIC_SCONTROL sctrl;
+	UINT64			guestID;
+	int ret=0;
+
+	DPRINT_ENTER(VMBUS);
+
+	if (!gHvContext.HypercallPage)
+	{
+		DPRINT_EXIT(VMBUS);
+		return ret;
+	}
+
+	// Check the version
+	version = ReadMsr(HV_X64_MSR_SVERSION);
+
+	DPRINT_INFO(VMBUS, "SynIC version: %llx", version);
+
+	// TODO: Handle SMP
+	if (gHvContext.GuestId == HV_XENLINUX_GUEST_ID)
+	{
+		DPRINT_INFO(VMBUS, "Skipping SIMP and SIEFP setup since it is already set.");
+
+		simp.AsUINT64 = ReadMsr(HV_X64_MSR_SIMP);
+		siefp.AsUINT64 = ReadMsr(HV_X64_MSR_SIEFP);
+
+		DPRINT_DBG(VMBUS, "Simp: %llx, Sifep: %llx", simp.AsUINT64, siefp.AsUINT64);
+
+		// Determine if we are running on xenlinux (ie x2v shim) or native linux
+		guestID = ReadMsr(HV_X64_MSR_GUEST_OS_ID);
+
+		if (guestID == HV_LINUX_GUEST_ID)
+		{
+			gHvContext.synICMessagePage[0] = GetVirtualAddress(simp.BaseSimpGpa << PAGE_SHIFT);
+			gHvContext.synICEventPage[0] = GetVirtualAddress(siefp.BaseSiefpGpa << PAGE_SHIFT);
+		}
+		else
+		{
+			DPRINT_ERR(VMBUS, "unknown guest id!!");
+			goto Cleanup;
+		}
+		DPRINT_DBG(VMBUS, "MAPPED: Simp: %p, Sifep: %p", gHvContext.synICMessagePage[0], gHvContext.synICEventPage[0]);
+	}
+	else
+	{
+		gHvContext.synICMessagePage[0] = PageAlloc(1);
+		if (gHvContext.synICMessagePage[0] == NULL)
+		{
+			DPRINT_ERR(VMBUS, "unable to allocate SYNIC message page!!");
+			goto Cleanup;
+		}
+
+		gHvContext.synICEventPage[0] = PageAlloc(1);
+		if (gHvContext.synICEventPage[0] == NULL)
+		{
+			DPRINT_ERR(VMBUS, "unable to allocate SYNIC event page!!");
+			goto Cleanup;
+		}
+
+		//
+		// Setup the Synic's message page
+		//
+		simp.AsUINT64 = ReadMsr(HV_X64_MSR_SIMP);
+		simp.SimpEnabled = 1;
+		simp.BaseSimpGpa = GetPhysicalAddress(gHvContext.synICMessagePage[0]) >> PAGE_SHIFT;
+
+		DPRINT_DBG(VMBUS, "HV_X64_MSR_SIMP msr set to: %llx", simp.AsUINT64);
+
+		WriteMsr(HV_X64_MSR_SIMP, simp.AsUINT64);
+
+		//
+		// Setup the Synic's event page
+		//
+		siefp.AsUINT64 = ReadMsr(HV_X64_MSR_SIEFP);
+		siefp.SiefpEnabled = 1;
+		siefp.BaseSiefpGpa = GetPhysicalAddress(gHvContext.synICEventPage[0]) >> PAGE_SHIFT;
+
+		DPRINT_DBG(VMBUS, "HV_X64_MSR_SIEFP msr set to: %llx", siefp.AsUINT64);
+
+		WriteMsr(HV_X64_MSR_SIEFP, siefp.AsUINT64);
+	}
+	//
+    // Setup the interception SINT.
+    //
+	//WriteMsr((HV_X64_MSR_SINT0 + HV_SYNIC_INTERCEPTION_SINT_INDEX),
+    //             interceptionSint.AsUINT64);
+
+    //
+    // Setup the shared SINT.
+    //
+	sharedSint.AsUINT64 = ReadMsr(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT);
+
+	sharedSint.AsUINT64 = 0;
+    sharedSint.Vector = irqVector; //HV_SHARED_SINT_IDT_VECTOR + 0x20;
+    sharedSint.Masked = FALSE;
+    sharedSint.AutoEoi = TRUE;
+
+	DPRINT_DBG(VMBUS, "HV_X64_MSR_SINT1 msr set to: %llx", sharedSint.AsUINT64);
+
+	WriteMsr(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.AsUINT64);
+
+	// Enable the global synic bit
+	sctrl.AsUINT64 = ReadMsr(HV_X64_MSR_SCONTROL);
+	sctrl.Enable = 1;
+
+    WriteMsr(HV_X64_MSR_SCONTROL, sctrl.AsUINT64);
+
+	gHvContext.SynICInitialized = TRUE;
+
+	DPRINT_EXIT(VMBUS);
+
+	return ret;
+
+Cleanup:
+	ret = -1;
+
+	if (gHvContext.GuestId == HV_LINUX_GUEST_ID)
+	{
+		if (gHvContext.synICEventPage[0])
+		{
+			PageFree(gHvContext.synICEventPage[0],1);
+		}
+
+		if (gHvContext.synICMessagePage[0])
+		{
+			PageFree(gHvContext.synICMessagePage[0], 1);
+		}
+	}
+
+	DPRINT_EXIT(VMBUS);
+
+	return ret;
+
+}
+
+/*++
+
+Name:
+	HvSynicCleanup()
+
+Description:
+	Cleanup routine for HvSynicInit().
+
+--*/
+VOID
+HvSynicCleanup(
+	VOID
+	)
+{
+    HV_SYNIC_SINT	sharedSint;
+	HV_SYNIC_SIMP	simp;
+	HV_SYNIC_SIEFP	siefp;
+
+	DPRINT_ENTER(VMBUS);
+
+	if (!gHvContext.SynICInitialized)
+	{
+		DPRINT_EXIT(VMBUS);
+		return;
+	}
+
+	sharedSint.AsUINT64 = ReadMsr(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT);
+
+	sharedSint.Masked = 1;
+
+	// Disable the interrupt
+    WriteMsr(HV_X64_MSR_SINT0 + VMBUS_MESSAGE_SINT, sharedSint.AsUINT64);
+
+	// Disable and free the resources only if we are running as native linux
+	// since in xenlinux, we are sharing the resources with the x2v shim
+	if (gHvContext.GuestId == HV_LINUX_GUEST_ID)
+	{
+		simp.AsUINT64 = ReadMsr(HV_X64_MSR_SIMP);
+		simp.SimpEnabled = 0;
+		simp.BaseSimpGpa = 0;
+
+		WriteMsr(HV_X64_MSR_SIMP, simp.AsUINT64);
+
+		siefp.AsUINT64 = ReadMsr(HV_X64_MSR_SIEFP);
+		siefp.SiefpEnabled = 0;
+		siefp.BaseSiefpGpa = 0;
+
+		WriteMsr(HV_X64_MSR_SIEFP, siefp.AsUINT64);
+
+		PageFree(gHvContext.synICMessagePage[0], 1);
+		PageFree(gHvContext.synICEventPage[0], 1);
+	}
+
+	DPRINT_EXIT(VMBUS);
+}
+
+
+// eof

drivers/staging/hv/Hv.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef __HV_H__
+#define __HV_H__
+
+#include "osd.h"
+
+#include "HvTypes.h"
+#include "HvStatus.h"
+//#include "HvVmApi.h"
+//#include "HvKeApi.h"
+//#include "HvMmApi.h"
+//#include "HvCpuApi.h"
+#include "HvHalApi.h"
+#include "HvVpApi.h"
+//#include "HvTrApi.h"
+#include "HvSynicApi.h"
+//#include "HvAmApi.h"
+//#include "HvHkApi.h"
+//#include "HvValApi.h"
+#include "HvHcApi.h"
+#include "HvPtApi.h"
+
+enum
+{
+    VMBUS_MESSAGE_CONNECTION_ID = 1,
+    VMBUS_MESSAGE_PORT_ID       = 1,
+    VMBUS_EVENT_CONNECTION_ID   = 2,
+    VMBUS_EVENT_PORT_ID         = 2,
+    VMBUS_MONITOR_CONNECTION_ID = 3,
+    VMBUS_MONITOR_PORT_ID       = 3,
+    VMBUS_MESSAGE_SINT          = 2
+};
+//
+// #defines
+//
+#define HV_PRESENT_BIT				0x80000000
+
+#define HV_XENLINUX_GUEST_ID_LO     0x00000000
+#define HV_XENLINUX_GUEST_ID_HI		0x0B00B135
+#define HV_XENLINUX_GUEST_ID		(((UINT64)HV_XENLINUX_GUEST_ID_HI << 32) | HV_XENLINUX_GUEST_ID_LO)
+
+#define HV_LINUX_GUEST_ID_LO		0x00000000
+#define HV_LINUX_GUEST_ID_HI		0xB16B00B5
+#define HV_LINUX_GUEST_ID			(((UINT64)HV_LINUX_GUEST_ID_HI << 32) | HV_LINUX_GUEST_ID_LO)
+
+#define HV_CPU_POWER_MANAGEMENT     (1 << 0)
+#define HV_RECOMMENDATIONS_MAX      4
+
+#define HV_X64_MAX                  5
+#define HV_CAPS_MAX                 8
+
+
+#define HV_HYPERCALL_PARAM_ALIGN	sizeof(UINT64)
+
+//
+// Service definitions
+//
+#define HV_SERVICE_PARENT_PORT (0)
+#define HV_SERVICE_PARENT_CONNECTION (0)
+
+#define HV_SERVICE_CONNECT_RESPONSE_SUCCESS             (0)
+#define HV_SERVICE_CONNECT_RESPONSE_INVALID_PARAMETER   (1)
+#define HV_SERVICE_CONNECT_RESPONSE_UNKNOWN_SERVICE     (2)
+#define HV_SERVICE_CONNECT_RESPONSE_CONNECTION_REJECTED (3)
+
+#define HV_SERVICE_CONNECT_REQUEST_MESSAGE_ID		(1)
+#define HV_SERVICE_CONNECT_RESPONSE_MESSAGE_ID		(2)
+#define HV_SERVICE_DISCONNECT_REQUEST_MESSAGE_ID	(3)
+#define HV_SERVICE_DISCONNECT_RESPONSE_MESSAGE_ID	(4)
+#define HV_SERVICE_MAX_MESSAGE_ID					(4)
+
+#define HV_SERVICE_PROTOCOL_VERSION (0x0010)
+#define HV_CONNECT_PAYLOAD_BYTE_COUNT 64
+
+//#define VMBUS_REVISION_NUMBER	6
+//#define VMBUS_PORT_ID			11		// Our local vmbus's port and connection id. Anything >0 is fine
+
+// 628180B8-308D-4c5e-B7DB-1BEB62E62EF4
+static const GUID VMBUS_SERVICE_ID = {.Data = {0xb8, 0x80, 0x81, 0x62, 0x8d, 0x30, 0x5e, 0x4c, 0xb7, 0xdb, 0x1b, 0xeb, 0x62, 0xe6, 0x2e, 0xf4} };
+
+#define MAX_NUM_CPUS	1
+
+
+typedef struct {
+	UINT64					Align8;
+	HV_INPUT_SIGNAL_EVENT	Event;
+} HV_INPUT_SIGNAL_EVENT_BUFFER;
+
+typedef struct {
+	UINT64	GuestId;			// XenLinux or native Linux. If XenLinux, the hypercall and synic pages has already been initialized
+	void*	HypercallPage;
+
+	BOOL	SynICInitialized;
+	// This is used as an input param to HvCallSignalEvent hypercall. The input param is immutable
+	// in our usage and must be dynamic mem (vs stack or global).
+	HV_INPUT_SIGNAL_EVENT_BUFFER *SignalEventBuffer;
+	HV_INPUT_SIGNAL_EVENT *SignalEventParam; // 8-bytes aligned of the buffer above
+
+	HANDLE	synICMessagePage[MAX_NUM_CPUS];
+	HANDLE	synICEventPage[MAX_NUM_CPUS];
+} HV_CONTEXT;
+
+extern HV_CONTEXT gHvContext;
+
+
+//
+// Inline routines
+//
+static inline unsigned long long ReadMsr(int msr)
+{
+	unsigned long long val;
+
+	RDMSR(msr, val);
+
+	return val;
+}
+
+static inline void WriteMsr(int msr, UINT64 val)
+{
+	WRMSR(msr, val);
+
+	return;
+}
+
+//
+// Hv Interface
+//
+INTERNAL int
+HvInit(
+    VOID
+    );
+
+INTERNAL VOID
+HvCleanup(
+    VOID
+    );
+
+INTERNAL HV_STATUS
+HvPostMessage(
+	HV_CONNECTION_ID connectionId,
+	HV_MESSAGE_TYPE  messageType,
+	PVOID            payload,
+	SIZE_T           payloadSize
+	);
+
+INTERNAL HV_STATUS
+HvSignalEvent(
+	VOID
+	);
+
+INTERNAL int
+HvSynicInit(
+	UINT32		irqVector
+	);
+
+INTERNAL VOID
+HvSynicCleanup(
+	VOID
+	);
+
+#endif // __HV_H__

drivers/staging/hv/RingBuffer.c

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#include "logging.h"
+#include "RingBuffer.h"
+
+//
+// #defines
+//
+
+// Amount of space to write to
+#define BYTES_AVAIL_TO_WRITE(r, w, z) ((w) >= (r))?((z) - ((w) - (r))):((r) - (w))
+
+
+/*++
+
+Name:
+	GetRingBufferAvailBytes()
+
+Description:
+	Get number of bytes available to read and to write to
+	for the specified ring buffer
+
+--*/
+static inline void
+GetRingBufferAvailBytes(RING_BUFFER_INFO *rbi, UINT32 *read, UINT32 *write)
+{
+	UINT32 read_loc,write_loc;
+
+	// Capture the read/write indices before they changed
+	read_loc = rbi->RingBuffer->ReadIndex;
+	write_loc = rbi->RingBuffer->WriteIndex;
+
+	*write = BYTES_AVAIL_TO_WRITE(read_loc, write_loc, rbi->RingDataSize);
+	*read = rbi->RingDataSize - *write;
+}
+
+/*++
+
+Name:
+	GetNextWriteLocation()
+
+Description:
+	Get the next write location for the specified ring buffer
+
+--*/
+static inline UINT32
+GetNextWriteLocation(RING_BUFFER_INFO* RingInfo)
+{
+	UINT32 next = RingInfo->RingBuffer->WriteIndex;
+
+	ASSERT(next < RingInfo->RingDataSize);
+
+	return next;
+}
+
+/*++
+
+Name:
+	SetNextWriteLocation()
+
+Description:
+	Set the next write location for the specified ring buffer
+
+--*/
+static inline void
+SetNextWriteLocation(RING_BUFFER_INFO* RingInfo, UINT32 NextWriteLocation)
+{
+	RingInfo->RingBuffer->WriteIndex = NextWriteLocation;
+}
+
+/*++
+
+Name:
+	GetNextReadLocation()
+
+Description:
+	Get the next read location for the specified ring buffer
+
+--*/
+static inline UINT32
+GetNextReadLocation(RING_BUFFER_INFO* RingInfo)
+{
+	UINT32 next = RingInfo->RingBuffer->ReadIndex;
+
+	ASSERT(next < RingInfo->RingDataSize);
+
+	return next;
+}
+
+/*++
+
+Name:
+	GetNextReadLocationWithOffset()
+
+Description:
+	Get the next read location + offset for the specified ring buffer.
+	This allows the caller to skip
+
+--*/
+static inline UINT32
+GetNextReadLocationWithOffset(RING_BUFFER_INFO* RingInfo, UINT32 Offset)
+{
+	UINT32 next = RingInfo->RingBuffer->ReadIndex;
+
+	ASSERT(next < RingInfo->RingDataSize);
+	next += Offset;
+	next %= RingInfo->RingDataSize;
+
+	return next;
+}
+
+/*++
+
+Name:
+	SetNextReadLocation()
+
+Description:
+	Set the next read location for the specified ring buffer
+
+--*/
+static inline void
+SetNextReadLocation(RING_BUFFER_INFO* RingInfo, UINT32 NextReadLocation)
+{
+	RingInfo->RingBuffer->ReadIndex = NextReadLocation;
+}
+
+
+/*++
+
+Name:
+	GetRingBuffer()
+
+Description:
+	Get the start of the ring buffer
+
+--*/
+static inline PVOID
+GetRingBuffer(RING_BUFFER_INFO* RingInfo)
+{
+	return (PVOID)RingInfo->RingBuffer->Buffer;
+}
+
+
+/*++
+
+Name:
+	GetRingBufferSize()
+
+Description:
+	Get the size of the ring buffer
+
+--*/
+static inline UINT32
+GetRingBufferSize(RING_BUFFER_INFO* RingInfo)
+{
+	return RingInfo->RingDataSize;
+}
+
+/*++
+
+Name:
+	GetRingBufferIndices()
+
+Description:
+	Get the read and write indices as UINT64 of the specified ring buffer
+
+--*/
+static inline UINT64
+GetRingBufferIndices(RING_BUFFER_INFO* RingInfo)
+{
+	return ((UINT64)RingInfo->RingBuffer->WriteIndex << 32) || RingInfo->RingBuffer->ReadIndex;
+}
+
+
+/*++
+
+Name:
+	DumpRingInfo()
+
+Description:
+	Dump out to console the ring buffer info
+
+--*/
+void
+DumpRingInfo(RING_BUFFER_INFO* RingInfo, char *Prefix)
+{
+	UINT32 bytesAvailToWrite;
+	UINT32 bytesAvailToRead;
+
+	GetRingBufferAvailBytes(RingInfo, &bytesAvailToRead, &bytesAvailToWrite);
+
+	DPRINT(VMBUS, DEBUG_RING_LVL, "%s <<ringinfo %p buffer %p avail write %u avail read %u read idx %u write idx %u>>",
+		Prefix,
+		RingInfo,
+		RingInfo->RingBuffer->Buffer,
+		bytesAvailToWrite,
+		bytesAvailToRead,
+		RingInfo->RingBuffer->ReadIndex,
+		RingInfo->RingBuffer->WriteIndex);
+}
+
+//
+// Internal routines
+//
+static UINT32
+CopyToRingBuffer(
+	RING_BUFFER_INFO	*RingInfo,
+	UINT32				StartWriteOffset,
+	PVOID				Src,
+	UINT32				SrcLen);
+
+static UINT32
+CopyFromRingBuffer(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Dest,
+	UINT32				DestLen,
+	UINT32				StartReadOffset);
+
+
+
+/*++
+
+Name:
+	RingBufferGetDebugInfo()
+
+Description:
+	Get various debug metrics for the specified ring buffer
+
+--*/
+void
+RingBufferGetDebugInfo(
+	RING_BUFFER_INFO		*RingInfo,
+	RING_BUFFER_DEBUG_INFO	*DebugInfo
+	)
+{
+	UINT32 bytesAvailToWrite;
+	UINT32 bytesAvailToRead;
+
+	if (RingInfo->RingBuffer)
+	{
+		GetRingBufferAvailBytes(RingInfo, &bytesAvailToRead, &bytesAvailToWrite);
+
+		DebugInfo->BytesAvailToRead = bytesAvailToRead;
+		DebugInfo->BytesAvailToWrite = bytesAvailToWrite;
+		DebugInfo->CurrentReadIndex = RingInfo->RingBuffer->ReadIndex;
+		DebugInfo->CurrentWriteIndex = RingInfo->RingBuffer->WriteIndex;
+
+		DebugInfo->CurrentInterruptMask = RingInfo->RingBuffer->InterruptMask;
+	}
+}
+
+
+/*++
+
+Name:
+	GetRingBufferInterruptMask()
+
+Description:
+	Get the interrupt mask for the specified ring buffer
+
+--*/
+UINT32
+GetRingBufferInterruptMask(
+	RING_BUFFER_INFO *rbi
+	)
+{
+	return rbi->RingBuffer->InterruptMask;
+}
+
+/*++
+
+Name:
+	RingBufferInit()
+
+Description:
+	Initialize the ring buffer
+
+--*/
+int
+RingBufferInit(
+	RING_BUFFER_INFO	*RingInfo,
+	VOID				*Buffer,
+	UINT32				BufferLen
+	)
+{
+	ASSERT(sizeof(RING_BUFFER) == PAGE_SIZE);
+
+	memset(RingInfo, 0, sizeof(RING_BUFFER_INFO));
+
+	RingInfo->RingBuffer = (RING_BUFFER*)Buffer;
+	RingInfo->RingBuffer->ReadIndex = RingInfo->RingBuffer->WriteIndex = 0;
+
+	RingInfo->RingSize = BufferLen;
+	RingInfo->RingDataSize = BufferLen - sizeof(RING_BUFFER);
+
+	RingInfo->RingLock = SpinlockCreate();
+
+	return 0;
+}
+
+/*++
+
+Name:
+	RingBufferCleanup()
+
+Description:
+	Cleanup the ring buffer
+
+--*/
+void
+RingBufferCleanup(
+	RING_BUFFER_INFO* RingInfo
+	)
+{
+	SpinlockClose(RingInfo->RingLock);
+}
+
+/*++
+
+Name:
+	RingBufferWrite()
+
+Description:
+	Write to the ring buffer
+
+--*/
+int
+RingBufferWrite(
+	RING_BUFFER_INFO*	OutRingInfo,
+	SG_BUFFER_LIST		SgBuffers[],
+	UINT32				SgBufferCount
+	)
+{
+	int i=0;
+	UINT32 byteAvailToWrite;
+	UINT32 byteAvailToRead;
+	UINT32 totalBytesToWrite=0;
+
+	volatile UINT32 nextWriteLocation;
+	UINT64 prevIndices=0;
+
+	DPRINT_ENTER(VMBUS);
+
+	for (i=0; i < SgBufferCount; i++)
+	{
+		totalBytesToWrite += SgBuffers[i].Length;
+	}
+
+	totalBytesToWrite += sizeof(UINT64);
+
+	SpinlockAcquire(OutRingInfo->RingLock);
+
+	GetRingBufferAvailBytes(OutRingInfo, &byteAvailToRead, &byteAvailToWrite);
+
+	DPRINT_DBG(VMBUS, "Writing %u bytes...", totalBytesToWrite);
+
+	//DumpRingInfo(OutRingInfo, "BEFORE ");
+
+	// If there is only room for the packet, assume it is full. Otherwise, the next time around, we think the ring buffer
+	// is empty since the read index == write index
+	if (byteAvailToWrite <= totalBytesToWrite)
+	{
+		DPRINT_DBG(VMBUS, "No more space left on outbound ring buffer (needed %u, avail %u)", totalBytesToWrite, byteAvailToWrite);
+
+		SpinlockRelease(OutRingInfo->RingLock);
+
+		DPRINT_EXIT(VMBUS);
+
+		return -1;
+	}
+
+	// Write to the ring buffer
+	nextWriteLocation = GetNextWriteLocation(OutRingInfo);
+
+	for (i=0; i < SgBufferCount; i++)
+	{
+		 nextWriteLocation = CopyToRingBuffer(OutRingInfo,
+												nextWriteLocation,
+												SgBuffers[i].Data,
+												SgBuffers[i].Length);
+	}
+
+	// Set previous packet start
+	prevIndices = GetRingBufferIndices(OutRingInfo);
+
+	nextWriteLocation = CopyToRingBuffer(OutRingInfo,
+												nextWriteLocation,
+												&prevIndices,
+												sizeof(UINT64));
+
+	// Make sure we flush all writes before updating the writeIndex
+	MemoryFence();
+
+	// Now, update the write location
+	SetNextWriteLocation(OutRingInfo, nextWriteLocation);
+
+	//DumpRingInfo(OutRingInfo, "AFTER ");
+
+	SpinlockRelease(OutRingInfo->RingLock);
+
+	DPRINT_EXIT(VMBUS);
+
+	return 0;
+}
+
+
+/*++
+
+Name:
+	RingBufferPeek()
+
+Description:
+	Read without advancing the read index
+
+--*/
+int
+RingBufferPeek(
+	RING_BUFFER_INFO*	InRingInfo,
+	void*				Buffer,
+	UINT32				BufferLen
+	)
+{
+	UINT32 bytesAvailToWrite;
+	UINT32 bytesAvailToRead;
+	UINT32 nextReadLocation=0;
+
+	SpinlockAcquire(InRingInfo->RingLock);
+
+	GetRingBufferAvailBytes(InRingInfo, &bytesAvailToRead, &bytesAvailToWrite);
+
+	// Make sure there is something to read
+	if (bytesAvailToRead < BufferLen )
+	{
+		//DPRINT_DBG(VMBUS, "got callback but not enough to read <avail to read %d read size %d>!!", bytesAvailToRead, BufferLen);
+
+		SpinlockRelease(InRingInfo->RingLock);
+
+		return -1;
+	}
+
+	// Convert to byte offset
+	nextReadLocation = GetNextReadLocation(InRingInfo);
+
+	nextReadLocation = CopyFromRingBuffer(InRingInfo,
+											Buffer,
+											BufferLen,
+											nextReadLocation);
+
+	SpinlockRelease(InRingInfo->RingLock);
+
+	return 0;
+}
+
+
+/*++
+
+Name:
+	RingBufferRead()
+
+Description:
+	Read and advance the read index
+
+--*/
+int
+RingBufferRead(
+	RING_BUFFER_INFO*	InRingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32				Offset
+	)
+{
+	UINT32 bytesAvailToWrite;
+	UINT32 bytesAvailToRead;
+	UINT32 nextReadLocation=0;
+	UINT64 prevIndices=0;
+
+	ASSERT(BufferLen > 0);
+
+	SpinlockAcquire(InRingInfo->RingLock);
+
+	GetRingBufferAvailBytes(InRingInfo, &bytesAvailToRead, &bytesAvailToWrite);
+
+	DPRINT_DBG(VMBUS, "Reading %u bytes...", BufferLen);
+
+	//DumpRingInfo(InRingInfo, "BEFORE ");
+
+	// Make sure there is something to read
+	if (bytesAvailToRead < BufferLen )
+	{
+		DPRINT_DBG(VMBUS, "got callback but not enough to read <avail to read %d read size %d>!!", bytesAvailToRead, BufferLen);
+
+		SpinlockRelease(InRingInfo->RingLock);
+
+		return -1;
+	}
+
+	nextReadLocation = GetNextReadLocationWithOffset(InRingInfo, Offset);
+
+	nextReadLocation = CopyFromRingBuffer(InRingInfo,
+											Buffer,
+											BufferLen,
+											nextReadLocation);
+
+	nextReadLocation = CopyFromRingBuffer(InRingInfo,
+											&prevIndices,
+											sizeof(UINT64),
+											nextReadLocation);
+
+	// Make sure all reads are done before we update the read index since
+	// the writer may start writing to the read area once the read index is updated
+	MemoryFence();
+
+	// Update the read index
+	SetNextReadLocation(InRingInfo, nextReadLocation);
+
+	//DumpRingInfo(InRingInfo, "AFTER ");
+
+	SpinlockRelease(InRingInfo->RingLock);
+
+	return 0;
+}
+
+
+/*++
+
+Name:
+	CopyToRingBuffer()
+
+Description:
+	Helper routine to copy from source to ring buffer.
+	Assume there is enough room. Handles wrap-around in dest case only!!
+
+--*/
+UINT32
+CopyToRingBuffer(
+	RING_BUFFER_INFO	*RingInfo,
+	UINT32				StartWriteOffset,
+	PVOID				Src,
+	UINT32				SrcLen)
+{
+	PVOID ringBuffer=GetRingBuffer(RingInfo);
+	UINT32 ringBufferSize=GetRingBufferSize(RingInfo);
+	UINT32 fragLen;
+
+	if (SrcLen > ringBufferSize - StartWriteOffset) // wrap-around detected!
+	{
+		DPRINT_DBG(VMBUS, "wrap-around detected!");
+
+		fragLen = ringBufferSize - StartWriteOffset;
+		memcpy(ringBuffer + StartWriteOffset, Src, fragLen);
+		memcpy(ringBuffer, Src + fragLen, SrcLen - fragLen);
+	}
+	else
+	{
+		memcpy(ringBuffer + StartWriteOffset, Src, SrcLen);
+	}
+
+	StartWriteOffset += SrcLen;
+	StartWriteOffset %= ringBufferSize;
+
+	return StartWriteOffset;
+}
+
+
+/*++
+
+Name:
+	CopyFromRingBuffer()
+
+Description:
+	Helper routine to copy to source from ring buffer.
+	Assume there is enough room. Handles wrap-around in src case only!!
+
+--*/
+UINT32
+CopyFromRingBuffer(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Dest,
+	UINT32				DestLen,
+	UINT32				StartReadOffset)
+{
+	PVOID ringBuffer=GetRingBuffer(RingInfo);
+	UINT32 ringBufferSize=GetRingBufferSize(RingInfo);
+
+	UINT32 fragLen;
+
+	if (DestLen > ringBufferSize - StartReadOffset) // wrap-around detected at the src
+	{
+		DPRINT_DBG(VMBUS, "src wrap-around detected!");
+
+		fragLen = ringBufferSize - StartReadOffset;
+
+		memcpy(Dest, ringBuffer + StartReadOffset, fragLen);
+		memcpy(Dest + fragLen, ringBuffer, DestLen - fragLen);
+	}
+	else
+	{
+		memcpy(Dest, ringBuffer + StartReadOffset, DestLen);
+	}
+
+	StartReadOffset += DestLen;
+	StartReadOffset %= ringBufferSize;
+
+	return StartReadOffset;
+}
+
+
+// eof

drivers/staging/hv/RingBuffer.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef _RING_BUFFER_H_
+#define _RING_BUFFER_H_
+
+#include "osd.h"
+
+typedef struct _SG_BUFFER_LIST {
+	PVOID	Data;
+	UINT32	Length;
+} SG_BUFFER_LIST;
+
+typedef struct _RING_BUFFER {
+    volatile UINT32	WriteIndex;     // Offset in bytes from the start of ring data below
+    volatile UINT32	ReadIndex;      // Offset in bytes from the start of ring data below
+
+	volatile UINT32 InterruptMask;
+	UINT8	Reserved[4084];			// Pad it to PAGE_SIZE so that data starts on page boundary
+	// NOTE: The InterruptMask field is used only for channels but since our vmbus connection
+	// also uses this data structure and its data starts here, we commented out this field.
+	// volatile UINT32 InterruptMask;
+	// Ring data starts here + RingDataStartOffset !!! DO NOT place any fields below this !!!
+    UINT8		Buffer[0];
+} STRUCT_PACKED RING_BUFFER;
+
+typedef struct _RING_BUFFER_INFO {
+    RING_BUFFER*	RingBuffer;
+    UINT32			RingSize;			// Include the shared header
+	HANDLE			RingLock;
+
+    UINT32			RingDataSize;		// < ringSize
+	UINT32			RingDataStartOffset;
+
+} RING_BUFFER_INFO;
+
+
+typedef struct _RING_BUFFER_DEBUG_INFO {
+	UINT32		CurrentInterruptMask;
+	UINT32		CurrentReadIndex;
+	UINT32		CurrentWriteIndex;
+	UINT32		BytesAvailToRead;
+	UINT32		BytesAvailToWrite;
+}RING_BUFFER_DEBUG_INFO;
+
+
+//
+// Interface
+//
+
+INTERNAL int
+RingBufferInit(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen
+	);
+
+INTERNAL void
+RingBufferCleanup(
+	RING_BUFFER_INFO	*RingInfo
+	);
+
+INTERNAL int
+RingBufferWrite(
+	RING_BUFFER_INFO	*RingInfo,
+	SG_BUFFER_LIST		SgBuffers[],
+	UINT32				SgBufferCount
+	);
+
+INTERNAL int
+RingBufferPeek(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen
+	);
+
+INTERNAL int
+RingBufferRead(
+	RING_BUFFER_INFO	*RingInfo,
+	PVOID				Buffer,
+	UINT32				BufferLen,
+	UINT32				Offset
+	);
+
+INTERNAL UINT32
+GetRingBufferInterruptMask(
+	RING_BUFFER_INFO *RingInfo
+	);
+
+INTERNAL void
+DumpRingInfo(
+	RING_BUFFER_INFO* RingInfo,
+	char *Prefix
+	);
+
+INTERNAL void
+RingBufferGetDebugInfo(
+	RING_BUFFER_INFO		*RingInfo,
+	RING_BUFFER_DEBUG_INFO	*DebugInfo
+	);
+
+#endif // _RING_BUFFER_H_

drivers/staging/hv/Sources.c

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#include "Vmbus.c"
+#include "Hv.c"
+#include "Connection.c"
+#include "Channel.c"
+#include "ChannelMgmt.c"
+#include "ChannelInterface.c"
+#include "RingBuffer.c"

drivers/staging/hv/VersionInfo.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#pragma once
+
+const char VersionDate[]=__DATE__;
+const char VersionTime[]=__TIME__;
+const char VersionDesc[]= "Version 2.0";

drivers/staging/hv/VmbusPrivate.h

+/*
+ *
+ * Copyright (c) 2009, Microsoft Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Authors:
+ *   Haiyang Zhang <haiyangz@microsoft.com>
+ *   Hank Janssen  <hjanssen@microsoft.com>
+ *
+ */
+
+
+#ifndef _VMBUS_PRIVATE_H_
+#define _VMBUS_PRIVATE_H_
+
+#ifndef INTERNAL
+#define INTERNAL static
+#endif
+
+#include "Hv.h"
+#include "VmbusApi.h"
+#include "Channel.h"
+#include "ChannelMgmt.h"
+#include "ChannelInterface.h"
+//#include "ChannelMessages.h"
+#include "RingBuffer.h"
+//#include "Packet.h"
+#include "List.h"
+
+//
+// Defines
+//
+
+// Maximum channels is determined by the size of the interrupt page which is PAGE_SIZE. 1/2 of PAGE_SIZE is for
+// send endpoint interrupt and the other is receive endpoint interrupt
+#define MAX_NUM_CHANNELS				(PAGE_SIZE >> 1) << 3  // 16348 channels
+
+// The value here must be in multiple of 32
+// TODO: Need to make this configurable
+#define MAX_NUM_CHANNELS_SUPPORTED		256
+
+//
+// Data types
+//
+
+typedef enum {
+	Disconnected,
+	Connecting,
+	Connected,
+	Disconnecting
+} VMBUS_CONNECT_STATE;
+
+#define MAX_SIZE_CHANNEL_MESSAGE			HV_MESSAGE_PAYLOAD_BYTE_COUNT
+
+typedef struct _VMBUS_CONNECTION {
+
+	VMBUS_CONNECT_STATE					ConnectState;
+
+	UINT32								NextGpadlHandle;
+
+	// Represents channel interrupts. Each bit position
+	// represents a channel.
+	// When a channel sends an interrupt via VMBUS, it
+	// finds its bit in the sendInterruptPage, set it and
+	// calls Hv to generate a port event. The other end
+	// receives the port event and parse the recvInterruptPage
+	// to see which bit is set
+	VOID*								InterruptPage;
+	VOID*								SendInterruptPage;
+	VOID*								RecvInterruptPage;
+
+	// 2 pages - 1st page for parent->child notification and 2nd is child->parent notification
+	VOID*								MonitorPages;
+	LIST_ENTRY							ChannelMsgList;
+	HANDLE								ChannelMsgLock;
+
+	// List of channels
+	LIST_ENTRY							ChannelList;
+	HANDLE								ChannelLock;
+
+	HANDLE								WorkQueue;
+} VMBUS_CONNECTION;
+
+
+typedef struct _VMBUS_MSGINFO {
+	// Bookkeeping stuff
+	LIST_ENTRY			MsgListEntry;
+
+	// Synchronize the request/response if needed
+	HANDLE				WaitEvent;
+
+	// The message itself
+	unsigned char		Msg[0];
+} VMBUS_MSGINFO;
+
+
+//
+// Externs
+//
+extern VMBUS_CONNECTION gVmbusConnection;
+
+//
+// General vmbus interface
+//
+INTERNAL DEVICE_OBJECT*
+VmbusChildDeviceCreate(
+	GUID deviceType,
+	GUID deviceInstance,
+	void *context);
+
+INTERNAL int
+VmbusChildDeviceAdd(
+	DEVICE_OBJECT* Device);
+
+INTERNAL void
+VmbusChildDeviceRemove(
+   DEVICE_OBJECT* Device);
+
+//INTERNAL void
+//VmbusChildDeviceDestroy(
+//	DEVICE_OBJECT*);
+
+INTERNAL VMBUS_CHANNEL*
+GetChannelFromRelId(
+	UINT32 relId
+	);
+
+//
+// Connection interface
+//
+INTERNAL int
+VmbusConnect(
+	VOID
+	);
+
+INTERNAL int
+VmbusDisconnect(
+	VOID
+	);
+
+INTERNAL int
+VmbusPostMessage(
+	PVOID			buffer,
+	SIZE_T			bufSize
+	);
+
+INTERNAL int
+VmbusSetEvent(
+	UINT32 childRelId
+	);
+
+INTERNAL VOID
+VmbusOnEvents(
+  VOID
+	);
+
+
+#endif // _VMBUS_PRIVATE_H_