/*
 *
 * Copyright (c) 2011, 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>
 *   K. Y. Srinivasan <kys@microsoft.com>
 *
 */

#ifndef _HYPERV_H
#define _HYPERV_H

#include <linux/scatterlist.h>
#include <linux/list.h>
#include <linux/timer.h>
#include <linux/workqueue.h>
#include <linux/completion.h>
#include <linux/device.h>


#include <asm/hyperv.h>

struct hv_guid {
	unsigned char data[16];
};

#define MAX_PAGE_BUFFER_COUNT				16
#define MAX_MULTIPAGE_BUFFER_COUNT			32 /* 128K */

#pragma pack(push, 1)

/* Single-page buffer */
struct hv_page_buffer {
	u32 len;
	u32 offset;
	u64 pfn;
};

/* Multiple-page buffer */
struct hv_multipage_buffer {
	/* Length and Offset determines the # of pfns in the array */
	u32 len;
	u32 offset;
	u64 pfn_array[MAX_MULTIPAGE_BUFFER_COUNT];
};

/* 0x18 includes the proprietary packet header */
#define MAX_PAGE_BUFFER_PACKET		(0x18 +			\
					(sizeof(struct hv_page_buffer) * \
					 MAX_PAGE_BUFFER_COUNT))
#define MAX_MULTIPAGE_BUFFER_PACKET	(0x18 +			\
					 sizeof(struct hv_multipage_buffer))


#pragma pack(pop)

struct hv_ring_buffer {
	/* Offset in bytes from the start of ring data below */
	u32 write_index;

	/* Offset in bytes from the start of ring data below */
	u32 read_index;

	u32 interrupt_mask;

	/* Pad it to PAGE_SIZE so that data starts on page boundary */
	u8	reserved[4084];

	/* NOTE:
	 * The interrupt_mask 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.
	 */

	/*
	 * Ring data starts here + RingDataStartOffset
	 * !!! DO NOT place any fields below this !!!
	 */
	u8 buffer[0];
} __packed;

struct hv_ring_buffer_info {
	struct hv_ring_buffer *ring_buffer;
	u32 ring_size;			/* Include the shared header */
	spinlock_t ring_lock;

	u32 ring_datasize;		/* < ring_size */
	u32 ring_data_startoffset;
};

struct hv_ring_buffer_debug_info {
	u32 current_interrupt_mask;
	u32 current_read_index;
	u32 current_write_index;
	u32 bytes_avail_toread;
	u32 bytes_avail_towrite;
};

/*
 * We use the same version numbering for all Hyper-V modules.
 *
 * Definition of versioning is as follows;
 *
 *	Major Number	Changes for these scenarios;
 *			1.	When a new version of Windows Hyper-V
 *				is released.
 *			2.	A Major change has occurred in the
 *				Linux IC's.
 *			(For example the merge for the first time
 *			into the kernel) Every time the Major Number
 *			changes, the Revision number is reset to 0.
 *	Minor Number	Changes when new functionality is added
 *			to the Linux IC's that is not a bug fix.
 *
 * 3.1 - Added completed hv_utils driver. Shutdown/Heartbeat/Timesync
 */
#define HV_DRV_VERSION           "3.1"


/*
 * A revision number of vmbus that is used for ensuring both ends on a
 * partition are using compatible versions.
 */
#define VMBUS_REVISION_NUMBER		13

/* Make maximum size of pipe payload of 16K */
#define MAX_PIPE_DATA_PAYLOAD		(sizeof(u8) * 16384)

/* Define PipeMode values. */
#define VMBUS_PIPE_TYPE_BYTE		0x00000000
#define VMBUS_PIPE_TYPE_MESSAGE		0x00000004

/* The size of the user defined data buffer for non-pipe offers. */
#define MAX_USER_DEFINED_BYTES		120

/* The size of the user defined data buffer for pipe offers. */
#define MAX_PIPE_USER_DEFINED_BYTES	116

/*
 * At the center of the Channel Management library is the Channel Offer. This
 * struct contains the fundamental information about an offer.
 */
struct vmbus_channel_offer {
	struct hv_guid if_type;
	struct hv_guid if_instance;
	u64 int_latency; /* in 100ns units */
	u32 if_revision;
	u32 server_ctx_size;	/* in bytes */
	u16 chn_flags;
	u16 mmio_megabytes;		/* in bytes * 1024 * 1024 */

	union {
		/* Non-pipes: The user has MAX_USER_DEFINED_BYTES bytes. */
		struct {
			unsigned char user_def[MAX_USER_DEFINED_BYTES];
		} std;

		/*
		 * Pipes:
		 * The following sructure is an integrated pipe protocol, which
		 * is implemented on top of standard user-defined data. Pipe
		 * clients have MAX_PIPE_USER_DEFINED_BYTES left for their own
		 * use.
		 */
		struct {
			u32  pipe_mode;
			unsigned char user_def[MAX_PIPE_USER_DEFINED_BYTES];
		} pipe;
	} u;
	u32 padding;
} __packed;

/* Server Flags */
#define VMBUS_CHANNEL_ENUMERATE_DEVICE_INTERFACE	1
#define VMBUS_CHANNEL_SERVER_SUPPORTS_TRANSFER_PAGES	2
#define VMBUS_CHANNEL_SERVER_SUPPORTS_GPADLS		4
#define VMBUS_CHANNEL_NAMED_PIPE_MODE			0x10
#define VMBUS_CHANNEL_LOOPBACK_OFFER			0x100
#define VMBUS_CHANNEL_PARENT_OFFER			0x200
#define VMBUS_CHANNEL_REQUEST_MONITORED_NOTIFICATION	0x400

struct vmpacket_descriptor {
	u16 type;
	u16 offset8;
	u16 len8;
	u16 flags;
	u64 trans_id;
} __packed;

struct vmpacket_header {
	u32 prev_pkt_start_offset;
	struct vmpacket_descriptor descriptor;
} __packed;

struct vmtransfer_page_range {
	u32 byte_count;
	u32 byte_offset;
} __packed;

struct vmtransfer_page_packet_header {
	struct vmpacket_descriptor d;
	u16 xfer_pageset_id;
	bool sender_owns_set;
	u8 reserved;
	u32 range_cnt;
	struct vmtransfer_page_range ranges[1];
} __packed;

struct vmgpadl_packet_header {
	struct vmpacket_descriptor d;
	u32 gpadl;
	u32 reserved;
} __packed;

struct vmadd_remove_transfer_page_set {
	struct vmpacket_descriptor d;
	u32 gpadl;
	u16 xfer_pageset_id;
	u16 reserved;
} __packed;

/*
 * This structure defines a range in guest physical space that can be made to
 * look virtually contiguous.
 */
struct gpa_range {
	u32 byte_count;
	u32 byte_offset;
	u64 pfn_array[0];
};

/*
 * This is the format for an Establish Gpadl packet, which contains a handle by
 * which this GPADL will be known and a set of GPA ranges associated with it.
 * This can be converted to a MDL by the guest OS.  If there are multiple GPA
 * ranges, then the resulting MDL will be "chained," representing multiple VA
 * ranges.
 */
struct vmestablish_gpadl {
	struct vmpacket_descriptor d;
	u32 gpadl;
	u32 range_cnt;
	struct gpa_range range[1];
} __packed;

/*
 * This is the format for a Teardown Gpadl packet, which indicates that the
 * GPADL handle in the Establish Gpadl packet will never be referenced again.
 */
struct vmteardown_gpadl {
	struct vmpacket_descriptor d;
	u32 gpadl;
	u32 reserved;	/* for alignment to a 8-byte boundary */
} __packed;

/*
 * This is the format for a GPA-Direct packet, which contains a set of GPA
 * ranges, in addition to commands and/or data.
 */
struct vmdata_gpa_direct {
	struct vmpacket_descriptor d;
	u32 reserved;
	u32 range_cnt;
	struct gpa_range range[1];
} __packed;

/* This is the format for a Additional Data Packet. */
struct vmadditional_data {
	struct vmpacket_descriptor d;
	u64 total_bytes;
	u32 offset;
	u32 byte_cnt;
	unsigned char data[1];
} __packed;

union vmpacket_largest_possible_header {
	struct vmpacket_descriptor simple_hdr;
	struct vmtransfer_page_packet_header xfer_page_hdr;
	struct vmgpadl_packet_header gpadl_hdr;
	struct vmadd_remove_transfer_page_set add_rm_xfer_page_hdr;
	struct vmestablish_gpadl establish_gpadl_hdr;
	struct vmteardown_gpadl teardown_gpadl_hdr;
	struct vmdata_gpa_direct data_gpa_direct_hdr;
};

#define VMPACKET_DATA_START_ADDRESS(__packet)	\
	(void *)(((unsigned char *)__packet) +	\
	 ((struct vmpacket_descriptor)__packet)->offset8 * 8)

#define VMPACKET_DATA_LENGTH(__packet)		\
	((((struct vmpacket_descriptor)__packet)->len8 -	\
	  ((struct vmpacket_descriptor)__packet)->offset8) * 8)

#define VMPACKET_TRANSFER_MODE(__packet)	\
	(((struct IMPACT)__packet)->type)

enum vmbus_packet_type {
	VM_PKT_INVALID				= 0x0,
	VM_PKT_SYNCH				= 0x1,
	VM_PKT_ADD_XFER_PAGESET			= 0x2,
	VM_PKT_RM_XFER_PAGESET			= 0x3,
	VM_PKT_ESTABLISH_GPADL			= 0x4,
	VM_PKT_TEARDOWN_GPADL			= 0x5,
	VM_PKT_DATA_INBAND			= 0x6,
	VM_PKT_DATA_USING_XFER_PAGES		= 0x7,
	VM_PKT_DATA_USING_GPADL			= 0x8,
	VM_PKT_DATA_USING_GPA_DIRECT		= 0x9,
	VM_PKT_CANCEL_REQUEST			= 0xa,
	VM_PKT_COMP				= 0xb,
	VM_PKT_DATA_USING_ADDITIONAL_PKT	= 0xc,
	VM_PKT_ADDITIONAL_DATA			= 0xd
};

#define VMBUS_DATA_PACKET_FLAG_COMPLETION_REQUESTED	1


/* Version 1 messages */
enum vmbus_channel_message_type {
	CHANNELMSG_INVALID			=  0,
	CHANNELMSG_OFFERCHANNEL		=  1,
	CHANNELMSG_RESCIND_CHANNELOFFER	=  2,
	CHANNELMSG_REQUESTOFFERS		=  3,
	CHANNELMSG_ALLOFFERS_DELIVERED	=  4,
	CHANNELMSG_OPENCHANNEL		=  5,
	CHANNELMSG_OPENCHANNEL_RESULT		=  6,
	CHANNELMSG_CLOSECHANNEL		=  7,
	CHANNELMSG_GPADL_HEADER		=  8,
	CHANNELMSG_GPADL_BODY			=  9,
	CHANNELMSG_GPADL_CREATED		= 10,
	CHANNELMSG_GPADL_TEARDOWN		= 11,
	CHANNELMSG_GPADL_TORNDOWN		= 12,
	CHANNELMSG_RELID_RELEASED		= 13,
	CHANNELMSG_INITIATE_CONTACT		= 14,
	CHANNELMSG_VERSION_RESPONSE		= 15,
	CHANNELMSG_UNLOAD			= 16,
#ifdef VMBUS_FEATURE_PARENT_OR_PEER_MEMORY_MAPPED_INTO_A_CHILD
	CHANNELMSG_VIEWRANGE_ADD		= 17,
	CHANNELMSG_VIEWRANGE_REMOVE		= 18,
#endif
	CHANNELMSG_COUNT
};

struct vmbus_channel_message_header {
	enum vmbus_channel_message_type msgtype;
	u32 padding;
} __packed;

/* Query VMBus Version parameters */
struct vmbus_channel_query_vmbus_version {
	struct vmbus_channel_message_header header;
	u32 version;
} __packed;

/* VMBus Version Supported parameters */
struct vmbus_channel_version_supported {
	struct vmbus_channel_message_header header;
	bool version_supported;
} __packed;

/* Offer Channel parameters */
struct vmbus_channel_offer_channel {
	struct vmbus_channel_message_header header;
	struct vmbus_channel_offer offer;
	u32 child_relid;
	u8 monitorid;
	bool monitor_allocated;
} __packed;

/* Rescind Offer parameters */
struct vmbus_channel_rescind_offer {
	struct vmbus_channel_message_header header;
	u32 child_relid;
} __packed;

/*
 * Request Offer -- no parameters, SynIC message contains the partition ID
 * Set Snoop -- no parameters, SynIC message contains the partition ID
 * Clear Snoop -- no parameters, SynIC message contains the partition ID
 * All Offers Delivered -- no parameters, SynIC message contains the partition
 *		           ID
 * Flush Client -- no parameters, SynIC message contains the partition ID
 */

/* Open Channel parameters */
struct vmbus_channel_open_channel {
	struct vmbus_channel_message_header header;

	/* Identifies the specific VMBus channel that is being opened. */
	u32 child_relid;

	/* ID making a particular open request at a channel offer unique. */
	u32 openid;

	/* GPADL for the channel's ring buffer. */
	u32 ringbuffer_gpadlhandle;

	/* GPADL for the channel's server context save area. */
	u32 server_contextarea_gpadlhandle;

	/*
	* The upstream ring buffer begins at offset zero in the memory
	* described by RingBufferGpadlHandle. The downstream ring buffer
	* follows it at this offset (in pages).
	*/
	u32 downstream_ringbuffer_pageoffset;

	/* User-specific data to be passed along to the server endpoint. */
	unsigned char userdata[MAX_USER_DEFINED_BYTES];
} __packed;

/* Open Channel Result parameters */
struct vmbus_channel_open_result {
	struct vmbus_channel_message_header header;
	u32 child_relid;
	u32 openid;
	u32 status;
} __packed;

/* Close channel parameters; */
struct vmbus_channel_close_channel {
	struct vmbus_channel_message_header header;
	u32 child_relid;
} __packed;

/* Channel Message GPADL */
#define GPADL_TYPE_RING_BUFFER		1
#define GPADL_TYPE_SERVER_SAVE_AREA	2
#define GPADL_TYPE_TRANSACTION		8

/*
 * The number of PFNs in a GPADL message is defined by the number of
 * pages that would be spanned by ByteCount and ByteOffset.  If the
 * implied number of PFNs won't fit in this packet, there will be a
 * follow-up packet that contains more.
 */
struct vmbus_channel_gpadl_header {
	struct vmbus_channel_message_header header;
	u32 child_relid;
	u32 gpadl;
	u16 range_buflen;
	u16 rangecount;
	struct gpa_range range[0];
} __packed;

/* This is the followup packet that contains more PFNs. */
struct vmbus_channel_gpadl_body {
	struct vmbus_channel_message_header header;
	u32 msgnumber;
	u32 gpadl;
	u64 pfn[0];
} __packed;

struct vmbus_channel_gpadl_created {
	struct vmbus_channel_message_header header;
	u32 child_relid;
	u32 gpadl;
	u32 creation_status;
} __packed;

struct vmbus_channel_gpadl_teardown {
	struct vmbus_channel_message_header header;
	u32 child_relid;
	u32 gpadl;
} __packed;

struct vmbus_channel_gpadl_torndown {
	struct vmbus_channel_message_header header;
	u32 gpadl;
} __packed;

#ifdef VMBUS_FEATURE_PARENT_OR_PEER_MEMORY_MAPPED_INTO_A_CHILD
struct vmbus_channel_view_range_add {
	struct vmbus_channel_message_header header;
	PHYSICAL_ADDRESS viewrange_base;
	u64 viewrange_length;
	u32 child_relid;
} __packed;

struct vmbus_channel_view_range_remove {
	struct vmbus_channel_message_header header;
	PHYSICAL_ADDRESS viewrange_base;
	u32 child_relid;
} __packed;
#endif

struct vmbus_channel_relid_released {
	struct vmbus_channel_message_header header;
	u32 child_relid;
} __packed;

struct vmbus_channel_initiate_contact {
	struct vmbus_channel_message_header header;
	u32 vmbus_version_requested;
	u32 padding2;
	u64 interrupt_page;
	u64 monitor_page1;
	u64 monitor_page2;
} __packed;

struct vmbus_channel_version_response {
	struct vmbus_channel_message_header header;
	bool version_supported;
} __packed;

enum vmbus_channel_state {
	CHANNEL_OFFER_STATE,
	CHANNEL_OPENING_STATE,
	CHANNEL_OPEN_STATE,
};

struct vmbus_channel_debug_info {
	u32 relid;
	enum vmbus_channel_state state;
	struct hv_guid interfacetype;
	struct hv_guid interface_instance;
	u32 monitorid;
	u32 servermonitor_pending;
	u32 servermonitor_latency;
	u32 servermonitor_connectionid;
	u32 clientmonitor_pending;
	u32 clientmonitor_latency;
	u32 clientmonitor_connectionid;

	struct hv_ring_buffer_debug_info inbound;
	struct hv_ring_buffer_debug_info outbound;
};

/*
 * Represents each channel msg on the vmbus connection This is a
 * variable-size data structure depending on the msg type itself
 */
struct vmbus_channel_msginfo {
	/* Bookkeeping stuff */
	struct list_head msglistentry;

	/* So far, this is only used to handle gpadl body message */
	struct list_head submsglist;

	/* Synchronize the request/response if needed */
	struct completion  waitevent;
	union {
		struct vmbus_channel_version_supported version_supported;
		struct vmbus_channel_open_result open_result;
		struct vmbus_channel_gpadl_torndown gpadl_torndown;
		struct vmbus_channel_gpadl_created gpadl_created;
		struct vmbus_channel_version_response version_response;
	} response;

	u32 msgsize;
	/*
	 * The channel message that goes out on the "wire".
	 * It will contain at minimum the VMBUS_CHANNEL_MESSAGE_HEADER header
	 */
	unsigned char msg[0];
};

struct vmbus_close_msg {
	struct vmbus_channel_msginfo info;
	struct vmbus_channel_close_channel msg;
};

struct vmbus_channel {
	struct list_head listentry;

	struct hv_device *device_obj;

	struct work_struct work;

	enum vmbus_channel_state state;
	/*
	 * For util channels, stash the
	 * the service index for easy access.
	 */
	s8 util_index;

	struct vmbus_channel_offer_channel offermsg;
	/*
	 * These are based on the OfferMsg.MonitorId.
	 * Save it here for easy access.
	 */
	u8 monitor_grp;
	u8 monitor_bit;

	u32 ringbuffer_gpadlhandle;

	/* Allocated memory for ring buffer */
	void *ringbuffer_pages;
	u32 ringbuffer_pagecount;
	struct hv_ring_buffer_info outbound;	/* send to parent */
	struct hv_ring_buffer_info inbound;	/* receive from parent */
	spinlock_t inbound_lock;
	struct workqueue_struct *controlwq;

	struct vmbus_close_msg close_msg;

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

	void (*onchannel_callback)(void *context);
	void *channel_callback_context;
};

void free_channel(struct vmbus_channel *channel);

void vmbus_onmessage(void *context);

int vmbus_request_offers(void);

/* The format must be the same as struct vmdata_gpa_direct */
struct vmbus_channel_packet_page_buffer {
	u16 type;
	u16 dataoffset8;
	u16 length8;
	u16 flags;
	u64 transactionid;
	u32 reserved;
	u32 rangecount;
	struct hv_page_buffer range[MAX_PAGE_BUFFER_COUNT];
} __packed;

/* The format must be the same as struct vmdata_gpa_direct */
struct vmbus_channel_packet_multipage_buffer {
	u16 type;
	u16 dataoffset8;
	u16 length8;
	u16 flags;
	u64 transactionid;
	u32 reserved;
	u32 rangecount;		/* Always 1 in this case */
	struct hv_multipage_buffer range;
} __packed;


extern int vmbus_open(struct vmbus_channel *channel,
			    u32 send_ringbuffersize,
			    u32 recv_ringbuffersize,
			    void *userdata,
			    u32 userdatalen,
			    void(*onchannel_callback)(void *context),
			    void *context);

extern void vmbus_close(struct vmbus_channel *channel);

extern int vmbus_sendpacket(struct vmbus_channel *channel,
				  const void *buffer,
				  u32 bufferLen,
				  u64 requestid,
				  enum vmbus_packet_type type,
				  u32 flags);

extern int vmbus_sendpacket_pagebuffer(struct vmbus_channel *channel,
					    struct hv_page_buffer pagebuffers[],
					    u32 pagecount,
					    void *buffer,
					    u32 bufferlen,
					    u64 requestid);

extern int vmbus_sendpacket_multipagebuffer(struct vmbus_channel *channel,
					struct hv_multipage_buffer *mpb,
					void *buffer,
					u32 bufferlen,
					u64 requestid);

extern int vmbus_establish_gpadl(struct vmbus_channel *channel,
				      void *kbuffer,
				      u32 size,
				      u32 *gpadl_handle);

extern int vmbus_teardown_gpadl(struct vmbus_channel *channel,
				     u32 gpadl_handle);

extern int vmbus_recvpacket(struct vmbus_channel *channel,
				  void *buffer,
				  u32 bufferlen,
				  u32 *buffer_actual_len,
				  u64 *requestid);

extern int vmbus_recvpacket_raw(struct vmbus_channel *channel,
				     void *buffer,
				     u32 bufferlen,
				     u32 *buffer_actual_len,
				     u64 *requestid);


extern void vmbus_get_debug_info(struct vmbus_channel *channel,
				     struct vmbus_channel_debug_info *debug);

extern void vmbus_ontimer(unsigned long data);


#define LOWORD(dw) ((unsigned short)(dw))
#define HIWORD(dw) ((unsigned short)(((unsigned int) (dw) >> 16) & 0xFFFF))


#define VMBUS				0x0001
#define STORVSC				0x0002
#define NETVSC				0x0004
#define INPUTVSC			0x0008
#define BLKVSC				0x0010
#define VMBUS_DRV			0x0100
#define STORVSC_DRV			0x0200
#define NETVSC_DRV			0x0400
#define INPUTVSC_DRV		0x0800
#define BLKVSC_DRV			0x1000

#define ALL_MODULES			(VMBUS		|\
							STORVSC		|\
							NETVSC		|\
							INPUTVSC	|\
							BLKVSC		|\
							VMBUS_DRV	|\
							STORVSC_DRV	|\
							NETVSC_DRV	|\
							INPUTVSC_DRV|\
							BLKVSC_DRV)

/* Logging Level */
#define ERROR_LVL				3
#define WARNING_LVL				4
#define INFO_LVL				6
#define DEBUG_LVL				7
#define DEBUG_LVL_ENTEREXIT			8
#define DEBUG_RING_LVL				9

extern unsigned int vmbus_loglevel;

#define DPRINT(mod, lvl, fmt, args...) do {\
	if ((mod & (HIWORD(vmbus_loglevel))) &&	\
	    (lvl <= LOWORD(vmbus_loglevel)))	\
		printk(KERN_DEBUG #mod": %s() " fmt "\n", __func__, ## args);\
	} while (0)

#define DPRINT_DBG(mod, fmt, args...) do {\
	if ((mod & (HIWORD(vmbus_loglevel))) &&		\
	    (DEBUG_LVL <= LOWORD(vmbus_loglevel)))	\
		printk(KERN_DEBUG #mod": %s() " fmt "\n", __func__, ## args);\
	} while (0)

#define DPRINT_INFO(mod, fmt, args...) do {\
	if ((mod & (HIWORD(vmbus_loglevel))) &&		\
	    (INFO_LVL <= LOWORD(vmbus_loglevel)))	\
		printk(KERN_INFO #mod": " fmt "\n", ## args);\
	} while (0)

#define DPRINT_WARN(mod, fmt, args...) do {\
	if ((mod & (HIWORD(vmbus_loglevel))) &&		\
	    (WARNING_LVL <= LOWORD(vmbus_loglevel)))	\
		printk(KERN_WARNING #mod": WARNING! " fmt "\n", ## args);\
	} while (0)

#define DPRINT_ERR(mod, fmt, args...) do {\
	if ((mod & (HIWORD(vmbus_loglevel))) &&		\
	    (ERROR_LVL <= LOWORD(vmbus_loglevel)))	\
		printk(KERN_ERR #mod": %s() ERROR!! " fmt "\n",	\
		       __func__, ## args);\
	} while (0)


struct hv_driver;
struct hv_device;

struct hv_dev_port_info {
	u32 int_mask;
	u32 read_idx;
	u32 write_idx;
	u32 bytes_avail_toread;
	u32 bytes_avail_towrite;
};

struct hv_device_info {
	u32 chn_id;
	u32 chn_state;
	struct hv_guid chn_type;
	struct hv_guid chn_instance;

	u32 monitor_id;
	u32 server_monitor_pending;
	u32 server_monitor_latency;
	u32 server_monitor_conn_id;
	u32 client_monitor_pending;
	u32 client_monitor_latency;
	u32 client_monitor_conn_id;

	struct hv_dev_port_info inbound;
	struct hv_dev_port_info outbound;
};

/* Base driver object */
struct hv_driver {
	const char *name;

	/* the device type supported by this driver */
	struct hv_guid dev_type;

	struct device_driver driver;

	int (*probe)(struct hv_device *);
	int (*remove)(struct hv_device *);
	void (*shutdown)(struct hv_device *);

};

/* Base device object */
struct hv_device {
	/* the device type id of this device */
	struct hv_guid dev_type;

	/* the device instance id of this device */
	struct hv_guid dev_instance;

	struct device device;

	struct vmbus_channel *channel;

	/* Device extension; */
	void *ext;
};


static inline struct hv_device *device_to_hv_device(struct device *d)
{
	return container_of(d, struct hv_device, device);
}

static inline struct hv_driver *drv_to_hv_drv(struct device_driver *d)
{
	return container_of(d, struct hv_driver, driver);
}


/* Vmbus interface */
int vmbus_child_driver_register(struct device_driver *drv);
void vmbus_child_driver_unregister(struct device_driver *drv);

/*
 * Common header for Hyper-V ICs
 */

#define ICMSGTYPE_NEGOTIATE		0
#define ICMSGTYPE_HEARTBEAT		1
#define ICMSGTYPE_KVPEXCHANGE		2
#define ICMSGTYPE_SHUTDOWN		3
#define ICMSGTYPE_TIMESYNC		4
#define ICMSGTYPE_VSS			5

#define ICMSGHDRFLAG_TRANSACTION	1
#define ICMSGHDRFLAG_REQUEST		2
#define ICMSGHDRFLAG_RESPONSE		4

#define HV_S_OK				0x00000000
#define HV_E_FAIL			0x80004005
#define HV_ERROR_NOT_SUPPORTED		0x80070032
#define HV_ERROR_MACHINE_LOCKED		0x800704F7

struct vmbuspipe_hdr {
	u32 flags;
	u32 msgsize;
} __packed;

struct ic_version {
	u16 major;
	u16 minor;
} __packed;

struct icmsg_hdr {
	struct ic_version icverframe;
	u16 icmsgtype;
	struct ic_version icvermsg;
	u16 icmsgsize;
	u32 status;
	u8 ictransaction_id;
	u8 icflags;
	u8 reserved[2];
} __packed;

struct icmsg_negotiate {
	u16 icframe_vercnt;
	u16 icmsg_vercnt;
	u32 reserved;
	struct ic_version icversion_data[1]; /* any size array */
} __packed;

struct shutdown_msg_data {
	u32 reason_code;
	u32 timeout_seconds;
	u32 flags;
	u8  display_message[2048];
} __packed;

struct heartbeat_msg_data {
	u64 seq_num;
	u32 reserved[8];
} __packed;

/* Time Sync IC defs */
#define ICTIMESYNCFLAG_PROBE	0
#define ICTIMESYNCFLAG_SYNC	1
#define ICTIMESYNCFLAG_SAMPLE	2

#ifdef __x86_64__
#define WLTIMEDELTA	116444736000000000L	/* in 100ns unit */
#else
#define WLTIMEDELTA	116444736000000000LL
#endif

struct ictimesync_data {
	u64 parenttime;
	u64 childtime;
	u64 roundtriptime;
	u8 flags;
} __packed;

/* Index for each IC struct in array hv_cb_utils[] */
#define HV_SHUTDOWN_MSG		0
#define HV_TIMESYNC_MSG		1
#define HV_HEARTBEAT_MSG	2
#define HV_KVP_MSG		3

struct hyperv_service_callback {
	u8 msg_type;
	char *log_msg;
	unsigned char data[16];
	struct vmbus_channel *channel;
	void (*callback) (void *context);
};

extern void prep_negotiate_resp(struct icmsg_hdr *,
				struct icmsg_negotiate *, u8 *);
extern void chn_cb_negotiate(void *);
extern struct hyperv_service_callback hv_cb_utils[];

#endif /* _HYPERV_H */