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  	   ˆÈÇ0ÆÅ  B   ˆl–Ü4ý( ©³( 	Å€fàB¦-ÿÈ„içŸ_†I|¥+a–Ü4ý()¨‰P@Šû€ÆÂ¦-ÿÈ ?÷     /* SPDX-License-Identifier: GPL-2.0-only */
/*
 *
 * Copyright (c) 2011, Microsoft Corporation.
 *
 * Authors:
 *   Haiyang Zhang <haiyangz@microsoft.com>
 *   Hank Janssen  <hjanssen@microsoft.com>
 *   K. Y. Srinivasan <kys@microsoft.com>
 */

#ifndef _HYPERV_H
#define _HYPERV_H

#include <uapi/linux/hyperv.h>

#include <linux/mm.h>
#include <linux/types.h>
#include <linux/scatterlist.h>
#include <linux/list.h>
#include <linux/timer.h>
#include <linux/completion.h>
#include <linux/device.h>
#include <linux/mod_devicetable.h>
#include <linux/interrupt.h>
#include <linux/reciprocal_div.h>
#include <hyperv/hvhdk.h>

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

#pragma pack(push, 1)

/*
 * Types for GPADL, decides is how GPADL header is created.
 *
 * It doesn't make much difference between BUFFER and RING if PAGE_SIZE is the
 * same as HV_HYP_PAGE_SIZE.
 *
 * If PAGE_SIZE is bigger than HV_HYP_PAGE_SIZE, the headers of ring buffers
 * will be of PAGE_SIZE, however, only the first HV_HYP_PAGE will be put
 * into gpadl, therefore the number for HV_HYP_PAGE and the indexes of each
 * HV_HYP_PAGE will be different between different types of GPADL, for example
 * if PAGE_SIZE is 64K:
 *
 * BUFFER:
 *
 * gva:    |--       64k      --|--       64k      --| ... |
 * gpa:    | 4k | 4k | ... | 4k | 4k | 4k | ... | 4k |
 * index:  0    1    2     15   16   17   18 .. 31   32 ...
 *         |    |    ...   |    |    |   ...    |   ...
 *         v    V          V    V    V          V
 * gpadl:  | 4k | 4k | ... | 4k | 4k | 4k | ... | 4k | ... |
 * index:  0    1    2 ... 15   16   17   18 .. 31   32 ...
 *
 * RING:
 *
 *         | header  |           data           | header  |     data      |
 * gva:    |-- 64k --|--       64k      --| ... |-- 64k --|-- 64k --| ... |
 * gpa:    | 4k | .. | 4k | 4k | ... | 4k | ... | 4k | .. | 4k | .. | ... |
 * index:  0    1    16   17   18    31   ...   n   n+1  n+16 ...         2n
 *         |         /    /          /          |         /               /
 *         |        /    /          /           |        /               /
 *         |       /    /   ...    /    ...     |       /      ...      /
 *         |      /    /          /             |      /               /
 *         |     /    /          /              |     /               /
 *         V    V    V          V               V    V               v
 * gpadl:  | 4k | 4k |   ...    |    ...        | 4k | 4k |  ...     |
 * index:  0    1    2   ...    16   ...       n-15 n-14 n-13  ...  2n-30
 */
enum hv_gpadl_type {
	HV_GPADL_BUFFER,
	HV_GPADL_RING
};

/* 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];
};

/*
 * Multiple-page buffer array; the pfn array is variable size:
 * The number of entries in the PFN array is determined by
 * "len" and "offset".
 */
struct hv_mpb_array {
	/* Length and Offset determines the # of pfns in the array */
	u32 len;
	u32 offset;
	u64 pfn_array[];
};

/* 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;

	/*
	 * WS2012/Win8 and later versions of Hyper-V implement interrupt
	 * driven flow management. The feature bit feat_pending_send_sz
	 * is set by the host on the host->guest ring buffer, and by the
	 * guest on the guest->host ring buffer.
	 *
	 * The meaning of the feature bit is a bit complex in that it has
	 * semantics that a