863 lines
		
	
	
		
			39 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			863 lines
		
	
	
		
			39 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /******************************************************************************
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|  * displif.h
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|  *
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|  * Unified display device I/O interface for Xen guest OSes.
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|  *
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|  * Permission is hereby granted, free of charge, to any person obtaining a copy
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|  * of this software and associated documentation files (the "Software"), to
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|  * deal in the Software without restriction, including without limitation the
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|  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
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|  * sell copies of the Software, and to permit persons to whom the Software is
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|  * furnished to do so, subject to the following conditions:
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|  *
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|  * The above copyright notice and this permission notice shall be included in
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|  * all copies or substantial portions of the Software.
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|  *
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|  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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|  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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|  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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|  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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|  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
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|  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
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|  * DEALINGS IN THE SOFTWARE.
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|  *
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|  * Copyright (C) 2016-2017 EPAM Systems Inc.
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|  *
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|  * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
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|  *          Oleksandr Grytsov <oleksandr_grytsov@epam.com>
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|  */
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| 
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| #ifndef __XEN_PUBLIC_IO_DISPLIF_H__
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| #define __XEN_PUBLIC_IO_DISPLIF_H__
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| 
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| #include "ring.h"
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| #include "../grant_table.h"
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| 
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| /*
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|  ******************************************************************************
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|  *                           Protocol version
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|  ******************************************************************************
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|  */
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| #define XENDISPL_PROTOCOL_VERSION	"1"
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| 
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| /*
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|  ******************************************************************************
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|  *                  Main features provided by the protocol
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|  ******************************************************************************
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|  * This protocol aims to provide a unified protocol which fits more
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|  * sophisticated use-cases than a framebuffer device can handle. At the
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|  * moment basic functionality is supported with the intention to be extended:
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|  *  o multiple dynamically allocated/destroyed framebuffers
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|  *  o buffers of arbitrary sizes
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|  *  o buffer allocation at either back or front end
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|  *  o better configuration options including multiple display support
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|  *
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|  * Note: existing fbif can be used together with displif running at the
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|  * same time, e.g. on Linux one provides framebuffer and another DRM/KMS
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|  *
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|  * Note: display resolution (XenStore's "resolution" property) defines
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|  * visible area of the virtual display. At the same time resolution of
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|  * the display and frame buffers may differ: buffers can be smaller, equal
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|  * or bigger than the visible area. This is to enable use-cases, where backend
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|  * may do some post-processing of the display and frame buffers supplied,
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|  * e.g. those buffers can be just a part of the final composition.
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|  *
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|  ******************************************************************************
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|  *                        Direction of improvements
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|  ******************************************************************************
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|  * Future extensions to the existing protocol may include:
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|  *  o display/connector cloning
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|  *  o allocation of objects other than display buffers
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|  *  o plane/overlay support
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|  *  o scaling support
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|  *  o rotation support
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|  *
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|  ******************************************************************************
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|  *                  Feature and Parameter Negotiation
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|  ******************************************************************************
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|  *
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|  * Front->back notifications: when enqueuing a new request, sending a
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|  * notification can be made conditional on xendispl_req (i.e., the generic
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|  * hold-off mechanism provided by the ring macros). Backends must set
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|  * xendispl_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()).
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|  *
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|  * Back->front notifications: when enqueuing a new response, sending a
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|  * notification can be made conditional on xendispl_resp (i.e., the generic
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|  * hold-off mechanism provided by the ring macros). Frontends must set
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|  * xendispl_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).
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|  *
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|  * The two halves of a para-virtual display driver utilize nodes within
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|  * XenStore to communicate capabilities and to negotiate operating parameters.
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|  * This section enumerates these nodes which reside in the respective front and
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|  * backend portions of XenStore, following the XenBus convention.
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|  *
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|  * All data in XenStore is stored as strings. Nodes specifying numeric
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|  * values are encoded in decimal. Integer value ranges listed below are
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|  * expressed as fixed sized integer types capable of storing the conversion
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|  * of a properly formated node string, without loss of information.
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|  *
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|  ******************************************************************************
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|  *                        Example configuration
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|  ******************************************************************************
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|  *
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|  * Note: depending on the use-case backend can expose more display connectors
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|  * than the underlying HW physically has by employing SW graphics compositors
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|  *
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|  * This is an example of backend and frontend configuration:
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|  *
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|  *--------------------------------- Backend -----------------------------------
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|  *
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|  * /local/domain/0/backend/vdispl/1/0/frontend-id = "1"
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|  * /local/domain/0/backend/vdispl/1/0/frontend = "/local/domain/1/device/vdispl/0"
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|  * /local/domain/0/backend/vdispl/1/0/state = "4"
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|  * /local/domain/0/backend/vdispl/1/0/versions = "1,2"
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|  *
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|  *--------------------------------- Frontend ----------------------------------
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|  *
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|  * /local/domain/1/device/vdispl/0/backend-id = "0"
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|  * /local/domain/1/device/vdispl/0/backend = "/local/domain/0/backend/vdispl/1/0"
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|  * /local/domain/1/device/vdispl/0/state = "4"
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|  * /local/domain/1/device/vdispl/0/version = "1"
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|  * /local/domain/1/device/vdispl/0/be-alloc = "1"
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|  *
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|  *-------------------------- Connector 0 configuration ------------------------
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|  *
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|  * /local/domain/1/device/vdispl/0/0/resolution = "1920x1080"
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|  * /local/domain/1/device/vdispl/0/0/req-ring-ref = "2832"
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|  * /local/domain/1/device/vdispl/0/0/req-event-channel = "15"
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|  * /local/domain/1/device/vdispl/0/0/evt-ring-ref = "387"
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|  * /local/domain/1/device/vdispl/0/0/evt-event-channel = "16"
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|  *
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|  *-------------------------- Connector 1 configuration ------------------------
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|  *
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|  * /local/domain/1/device/vdispl/0/1/resolution = "800x600"
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|  * /local/domain/1/device/vdispl/0/1/req-ring-ref = "2833"
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|  * /local/domain/1/device/vdispl/0/1/req-event-channel = "17"
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|  * /local/domain/1/device/vdispl/0/1/evt-ring-ref = "388"
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|  * /local/domain/1/device/vdispl/0/1/evt-event-channel = "18"
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|  *
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|  ******************************************************************************
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|  *                            Backend XenBus Nodes
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|  ******************************************************************************
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|  *
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|  *----------------------------- Protocol version ------------------------------
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|  *
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|  * versions
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|  *      Values:         <string>
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|  *
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|  *      List of XENDISPL_LIST_SEPARATOR separated protocol versions supported
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|  *      by the backend. For example "1,2,3".
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|  *
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|  ******************************************************************************
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|  *                            Frontend XenBus Nodes
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|  ******************************************************************************
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|  *
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|  *-------------------------------- Addressing ---------------------------------
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|  *
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|  * dom-id
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|  *      Values:         <uint16_t>
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|  *
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|  *      Domain identifier.
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|  *
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|  * dev-id
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|  *      Values:         <uint16_t>
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|  *
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|  *      Device identifier.
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|  *
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|  * conn-idx
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|  *      Values:         <uint8_t>
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|  *
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|  *      Zero based contigous index of the connector.
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|  *      /local/domain/<dom-id>/device/vdispl/<dev-id>/<conn-idx>/...
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|  *
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|  *----------------------------- Protocol version ------------------------------
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|  *
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|  * version
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|  *      Values:         <string>
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|  *
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|  *      Protocol version, chosen among the ones supported by the backend.
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|  *
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|  *------------------------- Backend buffer allocation -------------------------
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|  *
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|  * be-alloc
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|  *      Values:         "0", "1"
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|  *
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|  *      If value is set to "1", then backend can be a buffer provider/allocator
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|  *      for this domain during XENDISPL_OP_DBUF_CREATE operation (see below
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|  *      for negotiation).
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|  *      If value is not "1" or omitted frontend must allocate buffers itself.
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|  *
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|  *----------------------------- Connector settings ----------------------------
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|  *
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|  * unique-id
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|  *      Values:         <string>
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|  *
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|  *      After device instance initialization each connector is assigned a
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|  *      unique ID, so it can be identified by the backend by this ID.
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|  *      This can be UUID or such.
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|  *
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|  * resolution
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|  *      Values:         <width, uint32_t>x<height, uint32_t>
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|  *
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|  *      Width and height of the connector in pixels separated by
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|  *      XENDISPL_RESOLUTION_SEPARATOR. This defines visible area of the
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|  *      display.
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|  *
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|  *------------------ Connector Request Transport Parameters -------------------
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|  *
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|  * This communication path is used to deliver requests from frontend to backend
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|  * and get the corresponding responses from backend to frontend,
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|  * set up per connector.
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|  *
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|  * req-event-channel
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|  *      Values:         <uint32_t>
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|  *
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|  *      The identifier of the Xen connector's control event channel
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|  *      used to signal activity in the ring buffer.
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|  *
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|  * req-ring-ref
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|  *      Values:         <uint32_t>
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|  *
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|  *      The Xen grant reference granting permission for the backend to map
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|  *      a sole page of connector's control ring buffer.
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|  *
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|  *------------------- Connector Event Transport Parameters --------------------
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|  *
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|  * This communication path is used to deliver asynchronous events from backend
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|  * to frontend, set up per connector.
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|  *
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|  * evt-event-channel
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|  *      Values:         <uint32_t>
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|  *
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|  *      The identifier of the Xen connector's event channel
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|  *      used to signal activity in the ring buffer.
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|  *
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|  * evt-ring-ref
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|  *      Values:         <uint32_t>
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|  *
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|  *      The Xen grant reference granting permission for the backend to map
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|  *      a sole page of connector's event ring buffer.
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|  */
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| 
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| /*
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|  ******************************************************************************
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|  *                               STATE DIAGRAMS
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|  ******************************************************************************
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|  *
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|  * Tool stack creates front and back state nodes with initial state
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|  * XenbusStateInitialising.
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|  * Tool stack creates and sets up frontend display configuration
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|  * nodes per domain.
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|  *
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|  *-------------------------------- Normal flow --------------------------------
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|  *
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|  * Front                                Back
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|  * =================================    =====================================
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|  * XenbusStateInitialising              XenbusStateInitialising
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|  *                                       o Query backend device identification
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|  *                                         data.
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|  *                                       o Open and validate backend device.
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|  *                                                |
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|  *                                                |
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|  *                                                V
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|  *                                      XenbusStateInitWait
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|  *
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|  * o Query frontend configuration
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|  * o Allocate and initialize
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|  *   event channels per configured
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|  *   connector.
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|  * o Publish transport parameters
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|  *   that will be in effect during
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|  *   this connection.
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|  *              |
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|  *              |
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|  *              V
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|  * XenbusStateInitialised
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|  *
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|  *                                       o Query frontend transport parameters.
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|  *                                       o Connect to the event channels.
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|  *                                                |
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|  *                                                |
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|  *                                                V
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|  *                                      XenbusStateConnected
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|  *
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|  *  o Create and initialize OS
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|  *    virtual display connectors
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|  *    as per configuration.
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|  *              |
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|  *              |
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|  *              V
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|  * XenbusStateConnected
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|  *
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|  *                                      XenbusStateUnknown
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|  *                                      XenbusStateClosed
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|  *                                      XenbusStateClosing
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|  * o Remove virtual display device
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|  * o Remove event channels
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|  *              |
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|  *              |
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|  *              V
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|  * XenbusStateClosed
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|  *
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|  *------------------------------- Recovery flow -------------------------------
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|  *
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|  * In case of frontend unrecoverable errors backend handles that as
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|  * if frontend goes into the XenbusStateClosed state.
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|  *
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|  * In case of backend unrecoverable errors frontend tries removing
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|  * the virtualized device. If this is possible at the moment of error,
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|  * then frontend goes into the XenbusStateInitialising state and is ready for
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|  * new connection with backend. If the virtualized device is still in use and
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|  * cannot be removed, then frontend goes into the XenbusStateReconfiguring state
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|  * until either the virtualized device is removed or backend initiates a new
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|  * connection. On the virtualized device removal frontend goes into the
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|  * XenbusStateInitialising state.
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|  *
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|  * Note on XenbusStateReconfiguring state of the frontend: if backend has
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|  * unrecoverable errors then frontend cannot send requests to the backend
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|  * and thus cannot provide functionality of the virtualized device anymore.
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|  * After backend is back to normal the virtualized device may still hold some
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|  * state: configuration in use, allocated buffers, client application state etc.
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|  * In most cases, this will require frontend to implement complex recovery
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|  * reconnect logic. Instead, by going into XenbusStateReconfiguring state,
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|  * frontend will make sure no new clients of the virtualized device are
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|  * accepted, allow existing client(s) to exit gracefully by signaling error
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|  * state etc.
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|  * Once all the clients are gone frontend can reinitialize the virtualized
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|  * device and get into XenbusStateInitialising state again signaling the
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|  * backend that a new connection can be made.
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|  *
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|  * There are multiple conditions possible under which frontend will go from
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|  * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS
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|  * specific. For example:
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|  * 1. The underlying OS framework may provide callbacks to signal that the last
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|  *    client of the virtualized device has gone and the device can be removed
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|  * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue)
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|  *    to periodically check if this is the right time to re-try removal of
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|  *    the virtualized device.
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|  * 3. By any other means.
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|  *
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|  ******************************************************************************
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|  *                             REQUEST CODES
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|  ******************************************************************************
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|  * Request codes [0; 15] are reserved and must not be used
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|  */
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| 
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| #define XENDISPL_OP_DBUF_CREATE		0x10
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| #define XENDISPL_OP_DBUF_DESTROY	0x11
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| #define XENDISPL_OP_FB_ATTACH		0x12
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| #define XENDISPL_OP_FB_DETACH		0x13
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| #define XENDISPL_OP_SET_CONFIG		0x14
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| #define XENDISPL_OP_PG_FLIP		0x15
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| 
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| /*
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|  ******************************************************************************
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|  *                                 EVENT CODES
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|  ******************************************************************************
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|  */
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| #define XENDISPL_EVT_PG_FLIP		0x00
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| 
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| /*
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|  ******************************************************************************
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|  *               XENSTORE FIELD AND PATH NAME STRINGS, HELPERS
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|  ******************************************************************************
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|  */
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| #define XENDISPL_DRIVER_NAME		"vdispl"
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| 
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| #define XENDISPL_LIST_SEPARATOR		","
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| #define XENDISPL_RESOLUTION_SEPARATOR	"x"
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| 
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| #define XENDISPL_FIELD_BE_VERSIONS	"versions"
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| #define XENDISPL_FIELD_FE_VERSION	"version"
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| #define XENDISPL_FIELD_REQ_RING_REF	"req-ring-ref"
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| #define XENDISPL_FIELD_REQ_CHANNEL	"req-event-channel"
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| #define XENDISPL_FIELD_EVT_RING_REF	"evt-ring-ref"
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| #define XENDISPL_FIELD_EVT_CHANNEL	"evt-event-channel"
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| #define XENDISPL_FIELD_RESOLUTION	"resolution"
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| #define XENDISPL_FIELD_BE_ALLOC		"be-alloc"
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| #define XENDISPL_FIELD_UNIQUE_ID	"unique-id"
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| 
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| /*
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|  ******************************************************************************
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|  *                          STATUS RETURN CODES
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|  ******************************************************************************
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|  *
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|  * Status return code is zero on success and -XEN_EXX on failure.
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|  *
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|  ******************************************************************************
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|  *                              Assumptions
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|  ******************************************************************************
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|  * o usage of grant reference 0 as invalid grant reference:
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|  *   grant reference 0 is valid, but never exposed to a PV driver,
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|  *   because of the fact it is already in use/reserved by the PV console.
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|  * o all references in this document to page sizes must be treated
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|  *   as pages of size XEN_PAGE_SIZE unless otherwise noted.
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|  *
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|  ******************************************************************************
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|  *       Description of the protocol between frontend and backend driver
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|  ******************************************************************************
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|  *
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|  * The two halves of a Para-virtual display driver communicate with
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|  * each other using shared pages and event channels.
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|  * Shared page contains a ring with request/response packets.
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|  *
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|  * All reserved fields in the structures below must be 0.
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|  * Display buffers's cookie of value 0 is treated as invalid.
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|  * Framebuffer's cookie of value 0 is treated as invalid.
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|  *
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|  * For all request/response/event packets that use cookies:
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|  *   dbuf_cookie - uint64_t, unique to guest domain value used by the backend
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|  *     to map remote display buffer to its local one
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|  *   fb_cookie - uint64_t, unique to guest domain value used by the backend
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|  *     to map remote framebuffer to its local one
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|  *
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|  *---------------------------------- Requests ---------------------------------
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|  *
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|  * All requests/responses, which are not connector specific, must be sent over
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|  * control ring of the connector which has the index value of 0:
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|  *   /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref
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|  *
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|  * All request packets have the same length (64 octets)
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|  * All request packets have common header:
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|  *         0                1                 2               3        octet
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|  * +----------------+----------------+----------------+----------------+
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|  * |               id                |    operation   |   reserved     | 4
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|  * +----------------+----------------+----------------+----------------+
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|  * |                             reserved                              | 8
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|  * +----------------+----------------+----------------+----------------+
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|  *   id - uint16_t, private guest value, echoed in response
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|  *   operation - uint8_t, operation code, XENDISPL_OP_???
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|  *
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|  * Request dbuf creation - request creation of a display buffer.
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|  *         0                1                 2               3        octet
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|  * +----------------+----------------+----------------+----------------+
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|  * |               id                |_OP_DBUF_CREATE |   reserved     | 4
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|  * +----------------+----------------+----------------+----------------+
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|  * |                             reserved                              | 8
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|  * +----------------+----------------+----------------+----------------+
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|  * |                       dbuf_cookie low 32-bit                      | 12
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|  * +----------------+----------------+----------------+----------------+
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|  * |                       dbuf_cookie high 32-bit                     | 16
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|  * +----------------+----------------+----------------+----------------+
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|  * |                               width                               | 20
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|  * +----------------+----------------+----------------+----------------+
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|  * |                               height                              | 24
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|  * +----------------+----------------+----------------+----------------+
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|  * |                                bpp                                | 28
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|  * +----------------+----------------+----------------+----------------+
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|  * |                             buffer_sz                             | 32
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|  * +----------------+----------------+----------------+----------------+
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|  * |                               flags                               | 36
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|  * +----------------+----------------+----------------+----------------+
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|  * |                           gref_directory                          | 40
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|  * +----------------+----------------+----------------+----------------+
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|  * |                             reserved                              | 44
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|  * +----------------+----------------+----------------+----------------+
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|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
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|  * +----------------+----------------+----------------+----------------+
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|  * |                             reserved                              | 64
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|  * +----------------+----------------+----------------+----------------+
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|  *
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|  * Must be sent over control ring of the connector which has the index
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|  * value of 0:
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|  *   /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref
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|  * All unused bits in flags field must be set to 0.
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|  *
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|  * An attempt to create multiple display buffers with the same dbuf_cookie is
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|  * an error. dbuf_cookie can be re-used after destroying the corresponding
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|  * display buffer.
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|  *
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|  * Width and height of the display buffers can be smaller, equal or bigger
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|  * than the connector's resolution. Depth/pixel format of the individual
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|  * buffers can differ as well.
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|  *
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|  * width - uint32_t, width in pixels
 | |
|  * height - uint32_t, height in pixels
 | |
|  * bpp - uint32_t, bits per pixel
 | |
|  * buffer_sz - uint32_t, buffer size to be allocated, octets
 | |
|  * flags - uint32_t, flags of the operation
 | |
|  *   o XENDISPL_DBUF_FLG_REQ_ALLOC - if set, then backend is requested
 | |
|  *     to allocate the buffer with the parameters provided in this request.
 | |
|  *     Page directory is handled as follows:
 | |
|  *       Frontend on request:
 | |
|  *         o allocates pages for the directory (gref_directory,
 | |
|  *           gref_dir_next_page(s)
 | |
|  *         o grants permissions for the pages of the directory to the backend
 | |
|  *         o sets gref_dir_next_page fields
 | |
|  *       Backend on response:
 | |
|  *         o grants permissions for the pages of the buffer allocated to
 | |
|  *           the frontend
 | |
|  *         o fills in page directory with grant references
 | |
|  *           (gref[] in struct xendispl_page_directory)
 | |
|  * gref_directory - grant_ref_t, a reference to the first shared page
 | |
|  *   describing shared buffer references. At least one page exists. If shared
 | |
|  *   buffer size (buffer_sz) exceeds what can be addressed by this single page,
 | |
|  *   then reference to the next page must be supplied (see gref_dir_next_page
 | |
|  *   below)
 | |
|  */
 | |
| 
 | |
| #define XENDISPL_DBUF_FLG_REQ_ALLOC	(1 << 0)
 | |
| 
 | |
| struct xendispl_dbuf_create_req {
 | |
| 	uint64_t dbuf_cookie;
 | |
| 	uint32_t width;
 | |
| 	uint32_t height;
 | |
| 	uint32_t bpp;
 | |
| 	uint32_t buffer_sz;
 | |
| 	uint32_t flags;
 | |
| 	grant_ref_t gref_directory;
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Shared page for XENDISPL_OP_DBUF_CREATE buffer descriptor (gref_directory in
 | |
|  * the request) employs a list of pages, describing all pages of the shared
 | |
|  * data buffer:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        gref_dir_next_page                         | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                              gref[0]                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                              gref[i]                              | i*4+8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             gref[N - 1]                           | N*4+8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * gref_dir_next_page - grant_ref_t, reference to the next page describing
 | |
|  *   page directory. Must be 0 if there are no more pages in the list.
 | |
|  * gref[i] - grant_ref_t, reference to a shared page of the buffer
 | |
|  *   allocated at XENDISPL_OP_DBUF_CREATE
 | |
|  *
 | |
|  * Number of grant_ref_t entries in the whole page directory is not
 | |
|  * passed, but instead can be calculated as:
 | |
|  *   num_grefs_total = (XENDISPL_OP_DBUF_CREATE.buffer_sz + XEN_PAGE_SIZE - 1) /
 | |
|  *       XEN_PAGE_SIZE
 | |
|  */
 | |
| 
 | |
| struct xendispl_page_directory {
 | |
| 	grant_ref_t gref_dir_next_page;
 | |
| 	grant_ref_t gref[1]; /* Variable length */
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Request dbuf destruction - destroy a previously allocated display buffer:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                |_OP_DBUF_DESTROY|   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                       dbuf_cookie low 32-bit                      | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                       dbuf_cookie high 32-bit                     | 16
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 20
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * Must be sent over control ring of the connector which has the index
 | |
|  * value of 0:
 | |
|  *   /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref
 | |
|  */
 | |
| 
 | |
| struct xendispl_dbuf_destroy_req {
 | |
| 	uint64_t dbuf_cookie;
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Request framebuffer attachment - request attachment of a framebuffer to
 | |
|  * previously created display buffer.
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                | _OP_FB_ATTACH  |   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                       dbuf_cookie low 32-bit                      | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                       dbuf_cookie high 32-bit                     | 16
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie low 32-bit                       | 20
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie high 32-bit                      | 24
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                               width                               | 28
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                               height                              | 32
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                            pixel_format                           | 36
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 40
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * Must be sent over control ring of the connector which has the index
 | |
|  * value of 0:
 | |
|  *   /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref
 | |
|  * Width and height can be smaller, equal or bigger than the connector's
 | |
|  * resolution.
 | |
|  *
 | |
|  * An attempt to create multiple frame buffers with the same fb_cookie is
 | |
|  * an error. fb_cookie can be re-used after destroying the corresponding
 | |
|  * frame buffer.
 | |
|  *
 | |
|  * width - uint32_t, width in pixels
 | |
|  * height - uint32_t, height in pixels
 | |
|  * pixel_format - uint32_t, pixel format of the framebuffer, FOURCC code
 | |
|  */
 | |
| 
 | |
| struct xendispl_fb_attach_req {
 | |
| 	uint64_t dbuf_cookie;
 | |
| 	uint64_t fb_cookie;
 | |
| 	uint32_t width;
 | |
| 	uint32_t height;
 | |
| 	uint32_t pixel_format;
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Request framebuffer detach - detach a previously
 | |
|  * attached framebuffer from the display buffer in request:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                |  _OP_FB_DETACH |   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie low 32-bit                       | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie high 32-bit                      | 16
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 20
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * Must be sent over control ring of the connector which has the index
 | |
|  * value of 0:
 | |
|  *   /local/domain/<dom-id>/device/vdispl/<dev-id>/0/req-ring-ref
 | |
|  */
 | |
| 
 | |
| struct xendispl_fb_detach_req {
 | |
| 	uint64_t fb_cookie;
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Request configuration set/reset - request to set or reset
 | |
|  * the configuration/mode of the display:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                | _OP_SET_CONFIG |   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie low 32-bit                       | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie high 32-bit                      | 16
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                                 x                                 | 20
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                                 y                                 | 24
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                               width                               | 28
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                               height                              | 32
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                                bpp                                | 40
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 44
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * Pass all zeros to reset, otherwise command is treated as
 | |
|  * configuration set.
 | |
|  * Framebuffer's cookie defines which framebuffer/dbuf must be
 | |
|  * displayed while enabling display (applying configuration).
 | |
|  * x, y, width and height are bound by the connector's resolution and must not
 | |
|  * exceed it.
 | |
|  *
 | |
|  * x - uint32_t, starting position in pixels by X axis
 | |
|  * y - uint32_t, starting position in pixels by Y axis
 | |
|  * width - uint32_t, width in pixels
 | |
|  * height - uint32_t, height in pixels
 | |
|  * bpp - uint32_t, bits per pixel
 | |
|  */
 | |
| 
 | |
| struct xendispl_set_config_req {
 | |
| 	uint64_t fb_cookie;
 | |
| 	uint32_t x;
 | |
| 	uint32_t y;
 | |
| 	uint32_t width;
 | |
| 	uint32_t height;
 | |
| 	uint32_t bpp;
 | |
| };
 | |
| 
 | |
| /*
 | |
|  * Request page flip - request to flip a page identified by the framebuffer
 | |
|  * cookie:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                | _OP_PG_FLIP    |   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie low 32-bit                       | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie high 32-bit                      | 16
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 20
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  */
 | |
| 
 | |
| struct xendispl_page_flip_req {
 | |
| 	uint64_t fb_cookie;
 | |
| };
 | |
| 
 | |
| /*
 | |
|  *---------------------------------- Responses --------------------------------
 | |
|  *
 | |
|  * All response packets have the same length (64 octets)
 | |
|  *
 | |
|  * All response packets have common header:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                |            reserved             | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                              status                               | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * id - uint16_t, private guest value, echoed from request
 | |
|  * status - int32_t, response status, zero on success and -XEN_EXX on failure
 | |
|  *
 | |
|  *----------------------------------- Events ----------------------------------
 | |
|  *
 | |
|  * Events are sent via a shared page allocated by the front and propagated by
 | |
|  *   evt-event-channel/evt-ring-ref XenStore entries
 | |
|  * All event packets have the same length (64 octets)
 | |
|  * All event packets have common header:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                |      type      |   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  *
 | |
|  * id - uint16_t, event id, may be used by front
 | |
|  * type - uint8_t, type of the event
 | |
|  *
 | |
|  *
 | |
|  * Page flip complete event - event from back to front on page flip completed:
 | |
|  *         0                1                 2               3        octet
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |               id                |   _EVT_PG_FLIP |   reserved     | 4
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 8
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie low 32-bit                       | 12
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                        fb_cookie high 32-bit                      | 16
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 20
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  * |                             reserved                              | 64
 | |
|  * +----------------+----------------+----------------+----------------+
 | |
|  */
 | |
| 
 | |
| struct xendispl_pg_flip_evt {
 | |
| 	uint64_t fb_cookie;
 | |
| };
 | |
| 
 | |
| struct xendispl_req {
 | |
| 	uint16_t id;
 | |
| 	uint8_t operation;
 | |
| 	uint8_t reserved[5];
 | |
| 	union {
 | |
| 		struct xendispl_dbuf_create_req dbuf_create;
 | |
| 		struct xendispl_dbuf_destroy_req dbuf_destroy;
 | |
| 		struct xendispl_fb_attach_req fb_attach;
 | |
| 		struct xendispl_fb_detach_req fb_detach;
 | |
| 		struct xendispl_set_config_req set_config;
 | |
| 		struct xendispl_page_flip_req pg_flip;
 | |
| 		uint8_t reserved[56];
 | |
| 	} op;
 | |
| };
 | |
| 
 | |
| struct xendispl_resp {
 | |
| 	uint16_t id;
 | |
| 	uint8_t operation;
 | |
| 	uint8_t reserved;
 | |
| 	int32_t status;
 | |
| 	uint8_t reserved1[56];
 | |
| };
 | |
| 
 | |
| struct xendispl_evt {
 | |
| 	uint16_t id;
 | |
| 	uint8_t type;
 | |
| 	uint8_t reserved[5];
 | |
| 	union {
 | |
| 		struct xendispl_pg_flip_evt pg_flip;
 | |
| 		uint8_t reserved[56];
 | |
| 	} op;
 | |
| };
 | |
| 
 | |
| DEFINE_RING_TYPES(xen_displif, struct xendispl_req, struct xendispl_resp);
 | |
| 
 | |
| /*
 | |
|  ******************************************************************************
 | |
|  *                        Back to front events delivery
 | |
|  ******************************************************************************
 | |
|  * In order to deliver asynchronous events from back to front a shared page is
 | |
|  * allocated by front and its granted reference propagated to back via
 | |
|  * XenStore entries (evt-ring-ref/evt-event-channel).
 | |
|  * This page has a common header used by both front and back to synchronize
 | |
|  * access and control event's ring buffer, while back being a producer of the
 | |
|  * events and front being a consumer. The rest of the page after the header
 | |
|  * is used for event packets.
 | |
|  *
 | |
|  * Upon reception of an event(s) front may confirm its reception
 | |
|  * for either each event, group of events or none.
 | |
|  */
 | |
| 
 | |
| struct xendispl_event_page {
 | |
| 	uint32_t in_cons;
 | |
| 	uint32_t in_prod;
 | |
| 	uint8_t reserved[56];
 | |
| };
 | |
| 
 | |
| #define XENDISPL_EVENT_PAGE_SIZE XEN_PAGE_SIZE
 | |
| #define XENDISPL_IN_RING_OFFS (sizeof(struct xendispl_event_page))
 | |
| #define XENDISPL_IN_RING_SIZE (XENDISPL_EVENT_PAGE_SIZE - XENDISPL_IN_RING_OFFS)
 | |
| #define XENDISPL_IN_RING_LEN (XENDISPL_IN_RING_SIZE / sizeof(struct xendispl_evt))
 | |
| #define XENDISPL_IN_RING(page) \
 | |
| 	((struct xendispl_evt *)((char *)(page) + XENDISPL_IN_RING_OFFS))
 | |
| #define XENDISPL_IN_RING_REF(page, idx) \
 | |
| 	(XENDISPL_IN_RING((page))[(idx) % XENDISPL_IN_RING_LEN])
 | |
| 
 | |
| #endif /* __XEN_PUBLIC_IO_DISPLIF_H__ */
 |