/*
 *
 * 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 "include/osd.h"
#include "include/List.h"
#include "RingBuffer.h"

#include "include/VmbusChannelInterface.h"
#include "include/ChannelMessages.h"



typedef void (*PFN_CHANNEL_CALLBACK)(void * context);

typedef enum {
	CHANNEL_OFFER_STATE,
	CHANNEL_OPENING_STATE,
	CHANNEL_OPEN_STATE,
} VMBUS_CHANNEL_STATE;

typedef struct _VMBUS_CHANNEL {
	LIST_ENTRY					ListEntry;

	struct hv_device *DeviceObject;

	struct osd_timer *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. */
	u8						MonitorGroup;
	u8						MonitorBit;

	u32						RingBufferGpadlHandle;

	/* Allocated memory for ring buffer */
	void *						RingBufferPages;
	u32						RingBufferPageCount;
	RING_BUFFER_INFO			Outbound;	/* send to parent */
	RING_BUFFER_INFO			Inbound;	/* receive from parent */
	spinlock_t inbound_lock;
	struct workqueue_struct *ControlWQ;

	/* Channel callback are invoked in this workqueue context */
	/* HANDLE						dataWorkQueue; */

	PFN_CHANNEL_CALLBACK		OnChannelCallback;
	void *						ChannelCallbackContext;

} VMBUS_CHANNEL;


typedef struct _VMBUS_CHANNEL_DEBUG_INFO {
	u32						RelId;
	VMBUS_CHANNEL_STATE			State;
	GUID						InterfaceType;
    GUID						InterfaceInstance;
	u32						MonitorId;
	u32						ServerMonitorPending;
	u32						ServerMonitorLatency;
	u32						ServerMonitorConnectionId;
	u32						ClientMonitorPending;
	u32						ClientMonitorLatency;
	u32						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 */
	struct osd_waitevent *WaitEvent;

	VMBUS_CHANNEL_MESSAGE_RESPONSE Response;

	u32			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 */

static VMBUS_CHANNEL*
AllocVmbusChannel(
	void
	);

static void
FreeVmbusChannel(
	VMBUS_CHANNEL *Channel
	);

static void
VmbusOnChannelMessage(
	void *Context
	);

static int
VmbusChannelRequestOffers(
	void
	);

static void
VmbusChannelReleaseUnattachedChannels(
	void
	);

#endif /* _CHANNEL_MGMT_H_ */