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-rw-r--r--include/xen/arm/page-coherent.h26
-rw-r--r--include/xen/interface/io/9pfs.h36
-rw-r--r--include/xen/interface/io/displif.h854
-rw-r--r--include/xen/interface/io/kbdif.h458
-rw-r--r--include/xen/interface/io/ring.h143
-rw-r--r--include/xen/interface/io/sndif.h793
-rw-r--r--include/xen/xen-ops.h19
7 files changed, 2293 insertions, 36 deletions
diff --git a/include/xen/arm/page-coherent.h b/include/xen/arm/page-coherent.h
index 95ce6ac3a971..b1b4ecdf329a 100644
--- a/include/xen/arm/page-coherent.h
+++ b/include/xen/arm/page-coherent.h
@@ -2,8 +2,16 @@
#define _ASM_ARM_XEN_PAGE_COHERENT_H
#include <asm/page.h>
+#include <asm/dma-mapping.h>
#include <linux/dma-mapping.h>
+static inline const struct dma_map_ops *xen_get_dma_ops(struct device *dev)
+{
+ if (dev && dev->archdata.dev_dma_ops)
+ return dev->archdata.dev_dma_ops;
+ return get_arch_dma_ops(NULL);
+}
+
void __xen_dma_map_page(struct device *hwdev, struct page *page,
dma_addr_t dev_addr, unsigned long offset, size_t size,
enum dma_data_direction dir, unsigned long attrs);
@@ -19,13 +27,13 @@ void __xen_dma_sync_single_for_device(struct device *hwdev,
static inline void *xen_alloc_coherent_pages(struct device *hwdev, size_t size,
dma_addr_t *dma_handle, gfp_t flags, unsigned long attrs)
{
- return __generic_dma_ops(hwdev)->alloc(hwdev, size, dma_handle, flags, attrs);
+ return xen_get_dma_ops(hwdev)->alloc(hwdev, size, dma_handle, flags, attrs);
}
static inline void xen_free_coherent_pages(struct device *hwdev, size_t size,
void *cpu_addr, dma_addr_t dma_handle, unsigned long attrs)
{
- __generic_dma_ops(hwdev)->free(hwdev, size, cpu_addr, dma_handle, attrs);
+ xen_get_dma_ops(hwdev)->free(hwdev, size, cpu_addr, dma_handle, attrs);
}
static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
@@ -49,7 +57,7 @@ static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
* specific function.
*/
if (local)
- __generic_dma_ops(hwdev)->map_page(hwdev, page, offset, size, dir, attrs);
+ xen_get_dma_ops(hwdev)->map_page(hwdev, page, offset, size, dir, attrs);
else
__xen_dma_map_page(hwdev, page, dev_addr, offset, size, dir, attrs);
}
@@ -67,8 +75,8 @@ static inline void xen_dma_unmap_page(struct device *hwdev, dma_addr_t handle,
* specific function.
*/
if (pfn_valid(pfn)) {
- if (__generic_dma_ops(hwdev)->unmap_page)
- __generic_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);
+ if (xen_get_dma_ops(hwdev)->unmap_page)
+ xen_get_dma_ops(hwdev)->unmap_page(hwdev, handle, size, dir, attrs);
} else
__xen_dma_unmap_page(hwdev, handle, size, dir, attrs);
}
@@ -78,8 +86,8 @@ static inline void xen_dma_sync_single_for_cpu(struct device *hwdev,
{
unsigned long pfn = PFN_DOWN(handle);
if (pfn_valid(pfn)) {
- if (__generic_dma_ops(hwdev)->sync_single_for_cpu)
- __generic_dma_ops(hwdev)->sync_single_for_cpu(hwdev, handle, size, dir);
+ if (xen_get_dma_ops(hwdev)->sync_single_for_cpu)
+ xen_get_dma_ops(hwdev)->sync_single_for_cpu(hwdev, handle, size, dir);
} else
__xen_dma_sync_single_for_cpu(hwdev, handle, size, dir);
}
@@ -89,8 +97,8 @@ static inline void xen_dma_sync_single_for_device(struct device *hwdev,
{
unsigned long pfn = PFN_DOWN(handle);
if (pfn_valid(pfn)) {
- if (__generic_dma_ops(hwdev)->sync_single_for_device)
- __generic_dma_ops(hwdev)->sync_single_for_device(hwdev, handle, size, dir);
+ if (xen_get_dma_ops(hwdev)->sync_single_for_device)
+ xen_get_dma_ops(hwdev)->sync_single_for_device(hwdev, handle, size, dir);
} else
__xen_dma_sync_single_for_device(hwdev, handle, size, dir);
}
diff --git a/include/xen/interface/io/9pfs.h b/include/xen/interface/io/9pfs.h
new file mode 100644
index 000000000000..5b6c19dae5e2
--- /dev/null
+++ b/include/xen/interface/io/9pfs.h
@@ -0,0 +1,36 @@
+/*
+ * 9pfs.h -- Xen 9PFS transport
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (C) 2017 Stefano Stabellini <stefano@aporeto.com>
+ */
+
+#ifndef __XEN_PUBLIC_IO_9PFS_H__
+#define __XEN_PUBLIC_IO_9PFS_H__
+
+#include "xen/interface/io/ring.h"
+
+/*
+ * See docs/misc/9pfs.markdown in xen.git for the full specification:
+ * https://xenbits.xen.org/docs/unstable/misc/9pfs.html
+ */
+DEFINE_XEN_FLEX_RING_AND_INTF(xen_9pfs);
+
+#endif
diff --git a/include/xen/interface/io/displif.h b/include/xen/interface/io/displif.h
new file mode 100644
index 000000000000..596578d9be3e
--- /dev/null
+++ b/include/xen/interface/io/displif.h
@@ -0,0 +1,854 @@
+/******************************************************************************
+ * displif.h
+ *
+ * Unified display device I/O interface for Xen guest OSes.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Copyright (C) 2016-2017 EPAM Systems Inc.
+ *
+ * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ * Oleksandr Grytsov <oleksandr_grytsov@epam.com>
+ */
+
+#ifndef __XEN_PUBLIC_IO_DISPLIF_H__
+#define __XEN_PUBLIC_IO_DISPLIF_H__
+
+#include "ring.h"
+#include "../grant_table.h"
+
+/*
+ ******************************************************************************
+ * Protocol version
+ ******************************************************************************
+ */
+#define XENDISPL_PROTOCOL_VERSION "1"
+
+/*
+ ******************************************************************************
+ * Main features provided by the protocol
+ ******************************************************************************
+ * This protocol aims to provide a unified protocol which fits more
+ * sophisticated use-cases than a framebuffer device can handle. At the
+ * moment basic functionality is supported with the intention to be extended:
+ * o multiple dynamically allocated/destroyed framebuffers
+ * o buffers of arbitrary sizes
+ * o buffer allocation at either back or front end
+ * o better configuration options including multiple display support
+ *
+ * Note: existing fbif can be used together with displif running at the
+ * same time, e.g. on Linux one provides framebuffer and another DRM/KMS
+ *
+ * Note: display resolution (XenStore's "resolution" property) defines
+ * visible area of the virtual display. At the same time resolution of
+ * the display and frame buffers may differ: buffers can be smaller, equal
+ * or bigger than the visible area. This is to enable use-cases, where backend
+ * may do some post-processing of the display and frame buffers supplied,
+ * e.g. those buffers can be just a part of the final composition.
+ *
+ ******************************************************************************
+ * Direction of improvements
+ ******************************************************************************
+ * Future extensions to the existing protocol may include:
+ * o display/connector cloning
+ * o allocation of objects other than display buffers
+ * o plane/overlay support
+ * o scaling support
+ * o rotation support
+ *
+ ******************************************************************************
+ * Feature and Parameter Negotiation
+ ******************************************************************************
+ *
+ * Front->back notifications: when enqueuing a new request, sending a
+ * notification can be made conditional on xendispl_req (i.e., the generic
+ * hold-off mechanism provided by the ring macros). Backends must set
+ * xendispl_req appropriately (e.g., using RING_FINAL_CHECK_FOR_REQUESTS()).
+ *
+ * Back->front notifications: when enqueuing a new response, sending a
+ * notification can be made conditional on xendispl_resp (i.e., the generic
+ * hold-off mechanism provided by the ring macros). Frontends must set
+ * xendispl_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).
+ *
+ * The two halves of a para-virtual display driver utilize nodes within
+ * XenStore to communicate capabilities and to negotiate operating parameters.
+ * This section enumerates these nodes which reside in the respective front and
+ * backend portions of XenStore, following the XenBus convention.
+ *
+ * All data in XenStore is stored as strings. Nodes specifying numeric
+ * values are encoded in decimal. Integer value ranges listed below are
+ * expressed as fixed sized integer types capable of storing the conversion
+ * of a properly formated node string, without loss of information.
+ *
+ ******************************************************************************
+ * Example configuration
+ ******************************************************************************
+ *
+ * Note: depending on the use-case backend can expose more display connectors
+ * than the underlying HW physically has by employing SW graphics compositors
+ *
+ * This is an example of backend and frontend configuration:
+ *
+ *--------------------------------- Backend -----------------------------------
+ *
+ * /local/domain/0/backend/vdispl/1/0/frontend-id = "1"
+ * /local/domain/0/backend/vdispl/1/0/frontend = "/local/domain/1/device/vdispl/0"
+ * /local/domain/0/backend/vdispl/1/0/state = "4"
+ * /local/domain/0/backend/vdispl/1/0/versions = "1,2"
+ *
+ *--------------------------------- Frontend ----------------------------------
+ *
+ * /local/domain/1/device/vdispl/0/backend-id = "0"
+ * /local/domain/1/device/vdispl/0/backend = "/local/domain/0/backend/vdispl/1/0"
+ * /local/domain/1/device/vdispl/0/state = "4"
+ * /local/domain/1/device/vdispl/0/version = "1"
+ * /local/domain/1/device/vdispl/0/be-alloc = "1"
+ *
+ *-------------------------- Connector 0 configuration ------------------------
+ *
+ * /local/domain/1/device/vdispl/0/0/resolution = "1920x1080"
+ * /local/domain/1/device/vdispl/0/0/req-ring-ref = "2832"
+ * /local/domain/1/device/vdispl/0/0/req-event-channel = "15"
+ * /local/domain/1/device/vdispl/0/0/evt-ring-ref = "387"
+ * /local/domain/1/device/vdispl/0/0/evt-event-channel = "16"
+ *
+ *-------------------------- Connector 1 configuration ------------------------
+ *
+ * /local/domain/1/device/vdispl/0/1/resolution = "800x600"
+ * /local/domain/1/device/vdispl/0/1/req-ring-ref = "2833"
+ * /local/domain/1/device/vdispl/0/1/req-event-channel = "17"
+ * /local/domain/1/device/vdispl/0/1/evt-ring-ref = "388"
+ * /local/domain/1/device/vdispl/0/1/evt-event-channel = "18"
+ *
+ ******************************************************************************
+ * Backend XenBus Nodes
+ ******************************************************************************
+ *
+ *----------------------------- Protocol version ------------------------------
+ *
+ * versions
+ * Values: <string>
+ *
+ * List of XENDISPL_LIST_SEPARATOR separated protocol versions supported
+ * by the backend. For example "1,2,3".
+ *
+ ******************************************************************************
+ * Frontend XenBus Nodes
+ ******************************************************************************
+ *
+ *-------------------------------- Addressing ---------------------------------
+ *
+ * dom-id
+ * Values: <uint16_t>
+ *
+ * Domain identifier.
+ *
+ * dev-id
+ * Values: <uint16_t>
+ *
+ * Device identifier.
+ *
+ * conn-idx
+ * Values: <uint8_t>
+ *
+ * Zero based contigous index of the connector.
+ * /local/domain/<dom-id>/device/vdispl/<dev-id>/<conn-idx>/...
+ *
+ *----------------------------- Protocol version ------------------------------
+ *
+ * version
+ * Values: <string>
+ *
+ * Protocol version, chosen among the ones supported by the backend.
+ *
+ *------------------------- Backend buffer allocation -------------------------
+ *
+ * be-alloc
+ * Values: "0", "1"
+ *
+ * If value is set to "1", then backend can be a buffer provider/allocator
+ * for this domain during XENDISPL_OP_DBUF_CREATE operation (see below
+ * for negotiation).
+ * If value is not "1" or omitted frontend must allocate buffers itself.
+ *
+ *----------------------------- Connector settings ----------------------------
+ *
+ * resolution
+ * Values: <width, uint32_t>x<height, uint32_t>
+ *
+ * Width and height of the connector in pixels separated by
+ * XENDISPL_RESOLUTION_SEPARATOR. This defines visible area of the
+ * display.
+ *
+ *------------------ Connector Request Transport Parameters -------------------
+ *
+ * This communication path is used to deliver requests from frontend to backend
+ * and get the corresponding responses from backend to frontend,
+ * set up per connector.
+ *
+ * req-event-channel
+ * Values: <uint32_t>
+ *
+ * The identifier of the Xen connector's control event channel
+ * used to signal activity in the ring buffer.
+ *
+ * req-ring-ref
+ * Values: <uint32_t>
+ *
+ * The Xen grant reference granting permission for the backend to map
+ * a sole page of connector's control ring buffer.
+ *
+ *------------------- Connector Event Transport Parameters --------------------
+ *
+ * This communication path is used to deliver asynchronous events from backend
+ * to frontend, set up per connector.
+ *
+ * evt-event-channel
+ * Values: <uint32_t>
+ *
+ * The identifier of the Xen connector's event channel
+ * used to signal activity in the ring buffer.
+ *
+ * evt-ring-ref
+ * Values: <uint32_t>
+ *
+ * The Xen grant reference granting permission for the backend to map
+ * a sole page of connector's event ring buffer.
+ */
+
+/*
+ ******************************************************************************
+ * STATE DIAGRAMS
+ ******************************************************************************
+ *
+ * Tool stack creates front and back state nodes with initial state
+ * XenbusStateInitialising.
+ * Tool stack creates and sets up frontend display configuration
+ * nodes per domain.
+ *
+ *-------------------------------- Normal flow --------------------------------
+ *
+ * Front Back
+ * ================================= =====================================
+ * XenbusStateInitialising XenbusStateInitialising
+ * o Query backend device identification
+ * data.
+ * o Open and validate backend device.
+ * |
+ * |
+ * V
+ * XenbusStateInitWait
+ *
+ * o Query frontend configuration
+ * o Allocate and initialize
+ * event channels per configured
+ * connector.
+ * o Publish transport parameters
+ * that will be in effect during
+ * this connection.
+ * |
+ * |
+ * V
+ * XenbusStateInitialised
+ *
+ * o Query frontend transport parameters.
+ * o Connect to the event channels.
+ * |
+ * |
+ * V
+ * XenbusStateConnected
+ *
+ * o Create and initialize OS
+ * virtual display connectors
+ * as per configuration.
+ * |
+ * |
+ * V
+ * XenbusStateConnected
+ *
+ * XenbusStateUnknown
+ * XenbusStateClosed
+ * XenbusStateClosing
+ * o Remove virtual display device
+ * o Remove event channels
+ * |
+ * |
+ * V
+ * XenbusStateClosed
+ *
+ *------------------------------- Recovery flow -------------------------------
+ *
+ * In case of frontend unrecoverable errors backend handles that as
+ * if frontend goes into the XenbusStateClosed state.
+ *
+ * In case of backend unrecoverable errors frontend tries removing
+ * the virtualized device. If this is possible at the moment of error,
+ * then frontend goes into the XenbusStateInitialising state and is ready for
+ * new connection with backend. If the virtualized device is still in use and
+ * cannot be removed, then frontend goes into the XenbusStateReconfiguring state
+ * until either the virtualized device is removed or backend initiates a new
+ * connection. On the virtualized device removal frontend goes into the
+ * XenbusStateInitialising state.
+ *
+ * Note on XenbusStateReconfiguring state of the frontend: if backend has
+ * unrecoverable errors then frontend cannot send requests to the backend
+ * and thus cannot provide functionality of the virtualized device anymore.
+ * After backend is back to normal the virtualized device may still hold some
+ * state: configuration in use, allocated buffers, client application state etc.
+ * In most cases, this will require frontend to implement complex recovery
+ * reconnect logic. Instead, by going into XenbusStateReconfiguring state,
+ * frontend will make sure no new clients of the virtualized device are
+ * accepted, allow existing client(s) to exit gracefully by signaling error
+ * state etc.
+ * Once all the clients are gone frontend can reinitialize the virtualized
+ * device and get into XenbusStateInitialising state again signaling the
+ * backend that a new connection can be made.
+ *
+ * There are multiple conditions possible under which frontend will go from
+ * XenbusStateReconfiguring into XenbusStateInitialising, some of them are OS
+ * specific. For example:
+ * 1. The underlying OS framework may provide callbacks to signal that the last
+ * client of the virtualized device has gone and the device can be removed
+ * 2. Frontend can schedule a deferred work (timer/tasklet/workqueue)
+ * to periodically check if this is the right time to re-try removal of
+ * the virtualized device.
+ * 3. By any other means.
+ *
+ ******************************************************************************
+ * REQUEST CODES
+ ******************************************************************************
+ * Request codes [0; 15] are reserved and must not be used
+ */
+
+#define XENDISPL_OP_DBUF_CREATE 0x10
+#define XENDISPL_OP_DBUF_DESTROY 0x11
+#define XENDISPL_OP_FB_ATTACH 0x12
+#define XENDISPL_OP_FB_DETACH 0x13
+#define XENDISPL_OP_SET_CONFIG 0x14
+#define XENDISPL_OP_PG_FLIP 0x15
+
+/*
+ ******************************************************************************
+ * EVENT CODES
+ ******************************************************************************
+ */
+#define XENDISPL_EVT_PG_FLIP 0x00
+
+/*
+ ******************************************************************************
+ * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS
+ ******************************************************************************
+ */
+#define XENDISPL_DRIVER_NAME "vdispl"
+
+#define XENDISPL_LIST_SEPARATOR ","
+#define XENDISPL_RESOLUTION_SEPARATOR "x"
+
+#define XENDISPL_FIELD_BE_VERSIONS "versions"
+#define XENDISPL_FIELD_FE_VERSION "version"
+#define XENDISPL_FIELD_REQ_RING_REF "req-ring-ref"
+#define XENDISPL_FIELD_REQ_CHANNEL "req-event-channel"
+#define XENDISPL_FIELD_EVT_RING_REF "evt-ring-ref"
+#define XENDISPL_FIELD_EVT_CHANNEL "evt-event-channel"
+#define XENDISPL_FIELD_RESOLUTION "resolution"
+#define XENDISPL_FIELD_BE_ALLOC "be-alloc"
+
+/*
+ ******************************************************************************
+ * STATUS RETURN CODES
+ ******************************************************************************
+ *
+ * Status return code is zero on success and -XEN_EXX on failure.
+ *
+ ******************************************************************************
+ * Assumptions
+ ******************************************************************************
+ * o usage of grant reference 0 as invalid grant reference:
+ * grant reference 0 is valid, but never exposed to a PV driver,
+ * because of the fact it is already in use/reserved by the PV console.
+ * o all references in this document to page sizes must be treated
+ * as pages of size XEN_PAGE_SIZE unless otherwise noted.
+ *
+ ******************************************************************************
+ * Description of the protocol between frontend and backend driver
+ ******************************************************************************
+ *
+ * The two halves of a Para-virtual display driver communicate with
+ * each other using shared pages and event channels.
+ * Shared page contains a ring with request/response packets.
+ *
+ * All reserved fields in the structures below must be 0.
+ * Display buffers's cookie of value 0 is treated as invalid.
+ * Framebuffer's cookie of value 0 is treated as invalid.
+ *
+ * For all request/response/event packets that use cookies:
+ * dbuf_cookie - uint64_t, unique to guest domain value used by the backend
+ * to map remote display buffer to its local one
+ * fb_cookie - uint64_t, unique to guest domain value used by the backend
+ * to map remote framebuffer to its local one
+ *
+ *---------------------------------- Requests ---------------------------------
+ *
+ * All requests/responses, which are not connector specific, 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
+ *
+ * All request packets have the same length (64 octets)
+ * All request packets have common header:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * id - uint16_t, private guest value, echoed in response
+ * operation - uint8_t, operation code, XENDISPL_OP_???
+ *
+ * Request dbuf creation - request creation of a display buffer.
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id |_OP_DBUF_CREATE | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | dbuf_cookie low 32-bit | 12
+ * +----------------+----------------+----------------+----------------+
+ * | dbuf_cookie high 32-bit | 16
+ * +----------------+----------------+----------------+----------------+
+ * | width | 20
+ * +----------------+----------------+----------------+----------------+
+ * | height | 24
+ * +----------------+----------------+----------------+----------------+
+ * | bpp | 28
+ * +----------------+----------------+----------------+----------------+
+ * | buffer_sz | 32
+ * +----------------+----------------+----------------+----------------+
+ * | flags | 36
+ * +----------------+----------------+----------------+----------------+
+ * | gref_directory | 40
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 44
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | 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
+ * All unused bits in flags field must be set to 0.
+ *
+ * An attempt to create multiple display buffers with the same dbuf_cookie is
+ * an error. dbuf_cookie can be re-used after destroying the corresponding
+ * display buffer.
+ *
+ * Width and height of the display buffers can be smaller, equal or bigger
+ * than the connector's resolution. Depth/pixel format of the individual
+ * buffers can differ as well.
+ *
+ * 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
+ * +----------------+----------------+----------------+---------