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-rw-r--r--include/xen/interface/io/9pfs.h36
-rw-r--r--include/xen/interface/io/blkif.h302
-rw-r--r--include/xen/interface/io/console.h24
-rw-r--r--include/xen/interface/io/displif.h947
-rw-r--r--include/xen/interface/io/fbif.h143
-rw-r--r--include/xen/interface/io/kbdif.h560
-rw-r--r--include/xen/interface/io/netif.h957
-rw-r--r--include/xen/interface/io/pciif.h112
-rw-r--r--include/xen/interface/io/protocols.h22
-rw-r--r--include/xen/interface/io/pvcalls.h121
-rw-r--r--include/xen/interface/io/ring.h455
-rw-r--r--include/xen/interface/io/sndif.h1081
-rw-r--r--include/xen/interface/io/tpmif.h52
-rw-r--r--include/xen/interface/io/vscsiif.h229
-rw-r--r--include/xen/interface/io/xenbus.h51
-rw-r--r--include/xen/interface/io/xs_wire.h95
16 files changed, 5187 insertions, 0 deletions
diff --git a/include/xen/interface/io/9pfs.h b/include/xen/interface/io/9pfs.h
new file mode 100644
index 000000000..5b6c19dae
--- /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/blkif.h b/include/xen/interface/io/blkif.h
new file mode 100644
index 000000000..5e40041c7
--- /dev/null
+++ b/include/xen/interface/io/blkif.h
@@ -0,0 +1,302 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/******************************************************************************
+ * blkif.h
+ *
+ * Unified block-device I/O interface for Xen guest OSes.
+ *
+ * Copyright (c) 2003-2004, Keir Fraser
+ */
+
+#ifndef __XEN_PUBLIC_IO_BLKIF_H__
+#define __XEN_PUBLIC_IO_BLKIF_H__
+
+#include <xen/interface/io/ring.h>
+#include <xen/interface/grant_table.h>
+
+/*
+ * Front->back notifications: When enqueuing a new request, sending a
+ * notification can be made conditional on req_event (i.e., the generic
+ * hold-off mechanism provided by the ring macros). Backends must set
+ * req_event 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 rsp_event (i.e., the generic
+ * hold-off mechanism provided by the ring macros). Frontends must set
+ * rsp_event appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).
+ */
+
+typedef uint16_t blkif_vdev_t;
+typedef uint64_t blkif_sector_t;
+
+/*
+ * Multiple hardware queues/rings:
+ * If supported, the backend will write the key "multi-queue-max-queues" to
+ * the directory for that vbd, and set its value to the maximum supported
+ * number of queues.
+ * Frontends that are aware of this feature and wish to use it can write the
+ * key "multi-queue-num-queues" with the number they wish to use, which must be
+ * greater than zero, and no more than the value reported by the backend in
+ * "multi-queue-max-queues".
+ *
+ * For frontends requesting just one queue, the usual event-channel and
+ * ring-ref keys are written as before, simplifying the backend processing
+ * to avoid distinguishing between a frontend that doesn't understand the
+ * multi-queue feature, and one that does, but requested only one queue.
+ *
+ * Frontends requesting two or more queues must not write the toplevel
+ * event-channel and ring-ref keys, instead writing those keys under sub-keys
+ * having the name "queue-N" where N is the integer ID of the queue/ring for
+ * which those keys belong. Queues are indexed from zero.
+ * For example, a frontend with two queues must write the following set of
+ * queue-related keys:
+ *
+ * /local/domain/1/device/vbd/0/multi-queue-num-queues = "2"
+ * /local/domain/1/device/vbd/0/queue-0 = ""
+ * /local/domain/1/device/vbd/0/queue-0/ring-ref = "<ring-ref#0>"
+ * /local/domain/1/device/vbd/0/queue-0/event-channel = "<evtchn#0>"
+ * /local/domain/1/device/vbd/0/queue-1 = ""
+ * /local/domain/1/device/vbd/0/queue-1/ring-ref = "<ring-ref#1>"
+ * /local/domain/1/device/vbd/0/queue-1/event-channel = "<evtchn#1>"
+ *
+ * It is also possible to use multiple queues/rings together with
+ * feature multi-page ring buffer.
+ * For example, a frontend requests two queues/rings and the size of each ring
+ * buffer is two pages must write the following set of related keys:
+ *
+ * /local/domain/1/device/vbd/0/multi-queue-num-queues = "2"
+ * /local/domain/1/device/vbd/0/ring-page-order = "1"
+ * /local/domain/1/device/vbd/0/queue-0 = ""
+ * /local/domain/1/device/vbd/0/queue-0/ring-ref0 = "<ring-ref#0>"
+ * /local/domain/1/device/vbd/0/queue-0/ring-ref1 = "<ring-ref#1>"
+ * /local/domain/1/device/vbd/0/queue-0/event-channel = "<evtchn#0>"
+ * /local/domain/1/device/vbd/0/queue-1 = ""
+ * /local/domain/1/device/vbd/0/queue-1/ring-ref0 = "<ring-ref#2>"
+ * /local/domain/1/device/vbd/0/queue-1/ring-ref1 = "<ring-ref#3>"
+ * /local/domain/1/device/vbd/0/queue-1/event-channel = "<evtchn#1>"
+ *
+ */
+
+/*
+ * REQUEST CODES.
+ */
+#define BLKIF_OP_READ 0
+#define BLKIF_OP_WRITE 1
+/*
+ * Recognised only if "feature-barrier" is present in backend xenbus info.
+ * The "feature_barrier" node contains a boolean indicating whether barrier
+ * requests are likely to succeed or fail. Either way, a barrier request
+ * may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by
+ * the underlying block-device hardware. The boolean simply indicates whether
+ * or not it is worthwhile for the frontend to attempt barrier requests.
+ * If a backend does not recognise BLKIF_OP_WRITE_BARRIER, it should *not*
+ * create the "feature-barrier" node!
+ */
+#define BLKIF_OP_WRITE_BARRIER 2
+
+/*
+ * Recognised if "feature-flush-cache" is present in backend xenbus
+ * info. A flush will ask the underlying storage hardware to flush its
+ * non-volatile caches as appropriate. The "feature-flush-cache" node
+ * contains a boolean indicating whether flush requests are likely to
+ * succeed or fail. Either way, a flush request may fail at any time
+ * with BLKIF_RSP_EOPNOTSUPP if it is unsupported by the underlying
+ * block-device hardware. The boolean simply indicates whether or not it
+ * is worthwhile for the frontend to attempt flushes. If a backend does
+ * not recognise BLKIF_OP_WRITE_FLUSH_CACHE, it should *not* create the
+ * "feature-flush-cache" node!
+ */
+#define BLKIF_OP_FLUSH_DISKCACHE 3
+
+/*
+ * Recognised only if "feature-discard" is present in backend xenbus info.
+ * The "feature-discard" node contains a boolean indicating whether trim
+ * (ATA) or unmap (SCSI) - conviently called discard requests are likely
+ * to succeed or fail. Either way, a discard request
+ * may fail at any time with BLKIF_RSP_EOPNOTSUPP if it is unsupported by
+ * the underlying block-device hardware. The boolean simply indicates whether
+ * or not it is worthwhile for the frontend to attempt discard requests.
+ * If a backend does not recognise BLKIF_OP_DISCARD, it should *not*
+ * create the "feature-discard" node!
+ *
+ * Discard operation is a request for the underlying block device to mark
+ * extents to be erased. However, discard does not guarantee that the blocks
+ * will be erased from the device - it is just a hint to the device
+ * controller that these blocks are no longer in use. What the device
+ * controller does with that information is left to the controller.
+ * Discard operations are passed with sector_number as the
+ * sector index to begin discard operations at and nr_sectors as the number of
+ * sectors to be discarded. The specified sectors should be discarded if the
+ * underlying block device supports trim (ATA) or unmap (SCSI) operations,
+ * or a BLKIF_RSP_EOPNOTSUPP should be returned.
+ * More information about trim/unmap operations at:
+ * http://t13.org/Documents/UploadedDocuments/docs2008/
+ * e07154r6-Data_Set_Management_Proposal_for_ATA-ACS2.doc
+ * http://www.seagate.com/staticfiles/support/disc/manuals/
+ * Interface%20manuals/100293068c.pdf
+ * The backend can optionally provide three extra XenBus attributes to
+ * further optimize the discard functionality:
+ * 'discard-alignment' - Devices that support discard functionality may
+ * internally allocate space in units that are bigger than the exported
+ * logical block size. The discard-alignment parameter indicates how many bytes
+ * the beginning of the partition is offset from the internal allocation unit's
+ * natural alignment.
+ * 'discard-granularity' - Devices that support discard functionality may
+ * internally allocate space using units that are bigger than the logical block
+ * size. The discard-granularity parameter indicates the size of the internal
+ * allocation unit in bytes if reported by the device. Otherwise the
+ * discard-granularity will be set to match the device's physical block size.
+ * 'discard-secure' - All copies of the discarded sectors (potentially created
+ * by garbage collection) must also be erased. To use this feature, the flag
+ * BLKIF_DISCARD_SECURE must be set in the blkif_request_trim.
+ */
+#define BLKIF_OP_DISCARD 5
+
+/*
+ * Recognized if "feature-max-indirect-segments" in present in the backend
+ * xenbus info. The "feature-max-indirect-segments" node contains the maximum
+ * number of segments allowed by the backend per request. If the node is
+ * present, the frontend might use blkif_request_indirect structs in order to
+ * issue requests with more than BLKIF_MAX_SEGMENTS_PER_REQUEST (11). The
+ * maximum number of indirect segments is fixed by the backend, but the
+ * frontend can issue requests with any number of indirect segments as long as
+ * it's less than the number provided by the backend. The indirect_grefs field
+ * in blkif_request_indirect should be filled by the frontend with the
+ * grant references of the pages that are holding the indirect segments.
+ * These pages are filled with an array of blkif_request_segment that hold the
+ * information about the segments. The number of indirect pages to use is
+ * determined by the number of segments an indirect request contains. Every
+ * indirect page can contain a maximum of
+ * (PAGE_SIZE / sizeof(struct blkif_request_segment)) segments, so to
+ * calculate the number of indirect pages to use we have to do
+ * ceil(indirect_segments / (PAGE_SIZE / sizeof(struct blkif_request_segment))).
+ *
+ * If a backend does not recognize BLKIF_OP_INDIRECT, it should *not*
+ * create the "feature-max-indirect-segments" node!
+ */
+#define BLKIF_OP_INDIRECT 6
+
+/*
+ * Maximum scatter/gather segments per request.
+ * This is carefully chosen so that sizeof(struct blkif_ring) <= PAGE_SIZE.
+ * NB. This could be 12 if the ring indexes weren't stored in the same page.
+ */
+#define BLKIF_MAX_SEGMENTS_PER_REQUEST 11
+
+#define BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST 8
+
+struct blkif_request_segment {
+ grant_ref_t gref; /* reference to I/O buffer frame */
+ /* @first_sect: first sector in frame to transfer (inclusive). */
+ /* @last_sect: last sector in frame to transfer (inclusive). */
+ uint8_t first_sect, last_sect;
+};
+
+struct blkif_request_rw {
+ uint8_t nr_segments; /* number of segments */
+ blkif_vdev_t handle; /* only for read/write requests */
+#ifndef CONFIG_X86_32
+ uint32_t _pad1; /* offsetof(blkif_request,u.rw.id) == 8 */
+#endif
+ uint64_t id; /* private guest value, echoed in resp */
+ blkif_sector_t sector_number;/* start sector idx on disk (r/w only) */
+ struct blkif_request_segment seg[BLKIF_MAX_SEGMENTS_PER_REQUEST];
+} __attribute__((__packed__));
+
+struct blkif_request_discard {
+ uint8_t flag; /* BLKIF_DISCARD_SECURE or zero. */
+#define BLKIF_DISCARD_SECURE (1<<0) /* ignored if discard-secure=0 */
+ blkif_vdev_t _pad1; /* only for read/write requests */
+#ifndef CONFIG_X86_32
+ uint32_t _pad2; /* offsetof(blkif_req..,u.discard.id)==8*/
+#endif
+ uint64_t id; /* private guest value, echoed in resp */
+ blkif_sector_t sector_number;
+ uint64_t nr_sectors;
+ uint8_t _pad3;
+} __attribute__((__packed__));
+
+struct blkif_request_other {
+ uint8_t _pad1;
+ blkif_vdev_t _pad2; /* only for read/write requests */
+#ifndef CONFIG_X86_32
+ uint32_t _pad3; /* offsetof(blkif_req..,u.other.id)==8*/
+#endif
+ uint64_t id; /* private guest value, echoed in resp */
+} __attribute__((__packed__));
+
+struct blkif_request_indirect {
+ uint8_t indirect_op;
+ uint16_t nr_segments;
+#ifndef CONFIG_X86_32
+ uint32_t _pad1; /* offsetof(blkif_...,u.indirect.id) == 8 */
+#endif
+ uint64_t id;
+ blkif_sector_t sector_number;
+ blkif_vdev_t handle;
+ uint16_t _pad2;
+ grant_ref_t indirect_grefs[BLKIF_MAX_INDIRECT_PAGES_PER_REQUEST];
+#ifndef CONFIG_X86_32
+ uint32_t _pad3; /* make it 64 byte aligned */
+#else
+ uint64_t _pad3; /* make it 64 byte aligned */
+#endif
+} __attribute__((__packed__));
+
+struct blkif_request {
+ uint8_t operation; /* BLKIF_OP_??? */
+ union {
+ struct blkif_request_rw rw;
+ struct blkif_request_discard discard;
+ struct blkif_request_other other;
+ struct blkif_request_indirect indirect;
+ } u;
+} __attribute__((__packed__));
+
+struct blkif_response {
+ uint64_t id; /* copied from request */
+ uint8_t operation; /* copied from request */
+ int16_t status; /* BLKIF_RSP_??? */
+};
+
+/*
+ * STATUS RETURN CODES.
+ */
+ /* Operation not supported (only happens on barrier writes). */
+#define BLKIF_RSP_EOPNOTSUPP -2
+ /* Operation failed for some unspecified reason (-EIO). */
+#define BLKIF_RSP_ERROR -1
+ /* Operation completed successfully. */
+#define BLKIF_RSP_OKAY 0
+
+/*
+ * Generate blkif ring structures and types.
+ */
+
+DEFINE_RING_TYPES(blkif, struct blkif_request, struct blkif_response);
+
+#define VDISK_CDROM 0x1
+#define VDISK_REMOVABLE 0x2
+#define VDISK_READONLY 0x4
+
+/* Xen-defined major numbers for virtual disks, they look strangely
+ * familiar */
+#define XEN_IDE0_MAJOR 3
+#define XEN_IDE1_MAJOR 22
+#define XEN_SCSI_DISK0_MAJOR 8
+#define XEN_SCSI_DISK1_MAJOR 65
+#define XEN_SCSI_DISK2_MAJOR 66
+#define XEN_SCSI_DISK3_MAJOR 67
+#define XEN_SCSI_DISK4_MAJOR 68
+#define XEN_SCSI_DISK5_MAJOR 69
+#define XEN_SCSI_DISK6_MAJOR 70
+#define XEN_SCSI_DISK7_MAJOR 71
+#define XEN_SCSI_DISK8_MAJOR 128
+#define XEN_SCSI_DISK9_MAJOR 129
+#define XEN_SCSI_DISK10_MAJOR 130
+#define XEN_SCSI_DISK11_MAJOR 131
+#define XEN_SCSI_DISK12_MAJOR 132
+#define XEN_SCSI_DISK13_MAJOR 133
+#define XEN_SCSI_DISK14_MAJOR 134
+#define XEN_SCSI_DISK15_MAJOR 135
+
+#endif /* __XEN_PUBLIC_IO_BLKIF_H__ */
diff --git a/include/xen/interface/io/console.h b/include/xen/interface/io/console.h
new file mode 100644
index 000000000..85ca8b026
--- /dev/null
+++ b/include/xen/interface/io/console.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/******************************************************************************
+ * console.h
+ *
+ * Console I/O interface for Xen guest OSes.
+ *
+ * Copyright (c) 2005, Keir Fraser
+ */
+
+#ifndef __XEN_PUBLIC_IO_CONSOLE_H__
+#define __XEN_PUBLIC_IO_CONSOLE_H__
+
+typedef uint32_t XENCONS_RING_IDX;
+
+#define MASK_XENCONS_IDX(idx, ring) ((idx) & (sizeof(ring)-1))
+
+struct xencons_interface {
+ char in[1024];
+ char out[2048];
+ XENCONS_RING_IDX in_cons, in_prod;
+ XENCONS_RING_IDX out_cons, out_prod;
+};
+
+#endif /* __XEN_PUBLIC_IO_CONSOLE_H__ */
diff --git a/include/xen/interface/io/displif.h b/include/xen/interface/io/displif.h
new file mode 100644
index 000000000..d43ca0361
--- /dev/null
+++ b/include/xen/interface/io/displif.h
@@ -0,0 +1,947 @@
+/******************************************************************************
+ * 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 "2"
+#define XENDISPL_PROTOCOL_VERSION_INT 2
+
+/*
+ ******************************************************************************
+ * 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 ----------------------------
+ *
+ * unique-id
+ * Values: <string>
+ *
+ * After device instance initialization each connector is assigned a
+ * unique ID, so it can be identified by the backend by this ID.
+ * This can be UUID or such.
+ *
+ * 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.
+ * If backend provides extended display identification data (EDID) with
+ * XENDISPL_OP_GET_EDID request then EDID values must take precedence
+ * over the resolutions defined here.
+ *
+ *------------------ 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
+/* The below command is available in protocol version 2 and above. */
+#define XENDISPL_OP_GET_EDID 0x16
+
+/*
+ ******************************************************************************
+ * 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"
+#define XENDISPL_FIELD_UNIQUE_ID "unique-id"
+
+#define XENDISPL_EDID_BLOCK_SIZE 128
+#define XENDISPL_EDID_BLOCK_COUNT 256
+#define XENDISPL_EDID_MAX_SIZE (XENDISPL_EDID_BLOCK_SIZE * XENDISPL_EDID_BLOCK_COUNT)
+
+/*
+ ******************************************************************************
+ * 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
+ * +----------------+----------------+----------------+----------------+
+ * | data_ofs | 44
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 48
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | 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)
+ * data_ofs - uint32_t, offset of the data in the buffer, octets
+ */
+
+#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;
+ uint32_t data_ofs;
+};
+
+/*
+ * 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;
+};
+
+/*
+ * Request EDID - request EDID describing current connector:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | _OP_GET_EDID | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | buffer_sz | 8
+ * +----------------+----------------+----------------+----------------+
+ * | gref_directory | 12
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 16
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * Notes:
+ * - This command is not available in protocol version 1 and should be
+ * ignored.
+ * - This request is optional and if not supported then visible area
+ * is defined by the relevant XenStore's "resolution" property.
+ * - Shared buffer, allocated for EDID storage, must not be less then
+ * XENDISPL_EDID_MAX_SIZE octets.
+ *
+ * buffer_sz - uint32_t, buffer size to be allocated, octets
+ * gref_directory - grant_ref_t, a reference to the first shared page
+ * describing EDID buffer references. See XENDISPL_OP_DBUF_CREATE for
+ * grant page directory structure (struct xendispl_page_directory).
+ *
+ * See response format for this request.
+ */
+
+struct xendispl_get_edid_req {
+ uint32_t buffer_sz;
+ grant_ref_t gref_directory;
+};
+
+/*
+ *---------------------------------- 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
+ *
+ *
+ * Get EDID response - response for XENDISPL_OP_GET_EDID:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | status | 8
+ * +----------------+----------------+----------------+----------------+
+ * | edid_sz | 12
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 16
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * Notes:
+ * - This response is not available in protocol version 1 and should be
+ * ignored.
+ *
+ * edid_sz - uint32_t, size of the EDID, octets
+ */
+
+struct xendispl_get_edid_resp {
+ uint32_t edid_sz;
+};
+
+/*
+ *----------------------------------- 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;
+ struct xendispl_get_edid_req get_edid;
+ uint8_t reserved[56];
+ } op;
+};
+
+struct xendispl_resp {
+ uint16_t id;
+ uint8_t operation;
+ uint8_t reserved;
+ int32_t status;
+ union {
+ struct xendispl_get_edid_resp get_edid;
+ uint8_t reserved1[56];
+ } op;
+};
+
+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__ */
diff --git a/include/xen/interface/io/fbif.h b/include/xen/interface/io/fbif.h
new file mode 100644
index 000000000..974a51ed9
--- /dev/null
+++ b/include/xen/interface/io/fbif.h
@@ -0,0 +1,143 @@
+/*
+ * fbif.h -- Xen virtual frame buffer device
+ *
+ * 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) 2005 Anthony Liguori <aliguori@us.ibm.com>
+ * Copyright (C) 2006 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
+ */
+
+#ifndef __XEN_PUBLIC_IO_FBIF_H__
+#define __XEN_PUBLIC_IO_FBIF_H__
+
+/* Out events (frontend -> backend) */
+
+/*
+ * Out events may be sent only when requested by backend, and receipt
+ * of an unknown out event is an error.
+ */
+
+/* Event type 1 currently not used */
+/*
+ * Framebuffer update notification event
+ * Capable frontend sets feature-update in xenstore.
+ * Backend requests it by setting request-update in xenstore.
+ */
+#define XENFB_TYPE_UPDATE 2
+
+struct xenfb_update {
+ uint8_t type; /* XENFB_TYPE_UPDATE */
+ int32_t x; /* source x */
+ int32_t y; /* source y */
+ int32_t width; /* rect width */
+ int32_t height; /* rect height */
+};
+
+/*
+ * Framebuffer resize notification event
+ * Capable backend sets feature-resize in xenstore.
+ */
+#define XENFB_TYPE_RESIZE 3
+
+struct xenfb_resize {
+ uint8_t type; /* XENFB_TYPE_RESIZE */
+ int32_t width; /* width in pixels */
+ int32_t height; /* height in pixels */
+ int32_t stride; /* stride in bytes */
+ int32_t depth; /* depth in bits */
+ int32_t offset; /* start offset within framebuffer */
+};
+
+#define XENFB_OUT_EVENT_SIZE 40
+
+union xenfb_out_event {
+ uint8_t type;
+ struct xenfb_update update;
+ struct xenfb_resize resize;
+ char pad[XENFB_OUT_EVENT_SIZE];
+};
+
+/* In events (backend -> frontend) */
+
+/*
+ * Frontends should ignore unknown in events.
+ * No in events currently defined.
+ */
+
+#define XENFB_IN_EVENT_SIZE 40
+
+union xenfb_in_event {
+ uint8_t type;
+ char pad[XENFB_IN_EVENT_SIZE];
+};
+
+/* shared page */
+
+#define XENFB_IN_RING_SIZE 1024
+#define XENFB_IN_RING_LEN (XENFB_IN_RING_SIZE / XENFB_IN_EVENT_SIZE)
+#define XENFB_IN_RING_OFFS 1024
+#define XENFB_IN_RING(page) \
+ ((union xenfb_in_event *)((char *)(page) + XENFB_IN_RING_OFFS))
+#define XENFB_IN_RING_REF(page, idx) \
+ (XENFB_IN_RING((page))[(idx) % XENFB_IN_RING_LEN])
+
+#define XENFB_OUT_RING_SIZE 2048
+#define XENFB_OUT_RING_LEN (XENFB_OUT_RING_SIZE / XENFB_OUT_EVENT_SIZE)
+#define XENFB_OUT_RING_OFFS (XENFB_IN_RING_OFFS + XENFB_IN_RING_SIZE)
+#define XENFB_OUT_RING(page) \
+ ((union xenfb_out_event *)((char *)(page) + XENFB_OUT_RING_OFFS))
+#define XENFB_OUT_RING_REF(page, idx) \
+ (XENFB_OUT_RING((page))[(idx) % XENFB_OUT_RING_LEN])
+
+struct xenfb_page {
+ uint32_t in_cons, in_prod;
+ uint32_t out_cons, out_prod;
+
+ int32_t width; /* width of the framebuffer (in pixels) */
+ int32_t height; /* height of the framebuffer (in pixels) */
+ uint32_t line_length; /* length of a row of pixels (in bytes) */
+ uint32_t mem_length; /* length of the framebuffer (in bytes) */
+ uint8_t depth; /* depth of a pixel (in bits) */
+
+ /*
+ * Framebuffer page directory
+ *
+ * Each directory page holds PAGE_SIZE / sizeof(*pd)
+ * framebuffer pages, and can thus map up to PAGE_SIZE *
+ * PAGE_SIZE / sizeof(*pd) bytes. With PAGE_SIZE == 4096 and
+ * sizeof(unsigned long) == 4/8, that's 4 Megs 32 bit and 2
+ * Megs 64 bit. 256 directories give enough room for a 512
+ * Meg framebuffer with a max resolution of 12,800x10,240.
+ * Should be enough for a while with room leftover for
+ * expansion.
+ */
+ unsigned long pd[256];
+};
+
+/*
+ * Wart: xenkbd needs to know default resolution. Put it here until a
+ * better solution is found, but don't leak it to the backend.
+ */
+#ifdef __KERNEL__
+#define XENFB_WIDTH 800
+#define XENFB_HEIGHT 600
+#define XENFB_DEPTH 32
+#endif
+
+#endif
diff --git a/include/xen/interface/io/kbdif.h b/include/xen/interface/io/kbdif.h
new file mode 100644
index 000000000..5c7630d73
--- /dev/null
+++ b/include/xen/interface/io/kbdif.h
@@ -0,0 +1,560 @@
+/*
+ * kbdif.h -- Xen virtual keyboard/mouse
+ *
+ * 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) 2005 Anthony Liguori <aliguori@us.ibm.com>
+ * Copyright (C) 2006 Red Hat, Inc., Markus Armbruster <armbru@redhat.com>
+ */
+
+#ifndef __XEN_PUBLIC_IO_KBDIF_H__
+#define __XEN_PUBLIC_IO_KBDIF_H__
+
+/*
+ *****************************************************************************
+ * Feature and Parameter Negotiation
+ *****************************************************************************
+ *
+ * The two halves of a para-virtual 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 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.
+ *
+ *****************************************************************************
+ * Backend XenBus Nodes
+ *****************************************************************************
+ *
+ *---------------------------- Features supported ----------------------------
+ *
+ * Capable backend advertises supported features by publishing
+ * corresponding entries in XenStore and puts 1 as the value of the entry.
+ * If a feature is not supported then 0 must be set or feature entry omitted.
+ *
+ * feature-disable-keyboard
+ * Values: <uint>
+ *
+ * If there is no need to expose a virtual keyboard device by the
+ * frontend then this must be set to 1.
+ *
+ * feature-disable-pointer
+ * Values: <uint>
+ *
+ * If there is no need to expose a virtual pointer device by the
+ * frontend then this must be set to 1.
+ *
+ * feature-abs-pointer
+ * Values: <uint>
+ *
+ * Backends, which support reporting of absolute coordinates for pointer
+ * device should set this to 1.
+ *
+ * feature-multi-touch
+ * Values: <uint>
+ *
+ * Backends, which support reporting of multi-touch events
+ * should set this to 1.
+ *
+ * feature-raw-pointer
+ * Values: <uint>
+ *
+ * Backends, which support reporting raw (unscaled) absolute coordinates
+ * for pointer devices should set this to 1. Raw (unscaled) values have
+ * a range of [0, 0x7fff].
+ *
+ *----------------------- Device Instance Parameters ------------------------
+ *
+ * unique-id
+ * Values: <string>
+ *
+ * After device instance initialization it is assigned a unique ID,
+ * so every instance of the frontend can be identified by the backend
+ * by this ID. This can be UUID or such.
+ *
+ *------------------------- Pointer Device Parameters ------------------------
+ *
+ * width
+ * Values: <uint>
+ *
+ * Maximum X coordinate (width) to be used by the frontend
+ * while reporting input events, pixels, [0; UINT32_MAX].
+ *
+ * height
+ * Values: <uint>
+ *
+ * Maximum Y coordinate (height) to be used by the frontend
+ * while reporting input events, pixels, [0; UINT32_MAX].
+ *
+ *----------------------- Multi-touch Device Parameters ----------------------
+ *
+ * multi-touch-num-contacts
+ * Values: <uint>
+ *
+ * Number of simultaneous touches reported.
+ *
+ * multi-touch-width
+ * Values: <uint>
+ *
+ * Width of the touch area to be used by the frontend
+ * while reporting input events, pixels, [0; UINT32_MAX].
+ *
+ * multi-touch-height
+ * Values: <uint>
+ *
+ * Height of the touch area to be used by the frontend
+ * while reporting input events, pixels, [0; UINT32_MAX].
+ *
+ *****************************************************************************
+ * Frontend XenBus Nodes
+ *****************************************************************************
+ *
+ *------------------------------ Feature request -----------------------------
+ *
+ * Capable frontend requests features from backend via setting corresponding
+ * entries to 1 in XenStore. Requests for features not advertised as supported
+ * by the backend have no effect.
+ *
+ * request-abs-pointer
+ * Values: <uint>
+ *
+ * Request backend to report absolute pointer coordinates
+ * (XENKBD_TYPE_POS) instead of relative ones (XENKBD_TYPE_MOTION).
+ *
+ * request-multi-touch
+ * Values: <uint>
+ *
+ * Request backend to report multi-touch events.
+ *
+ * request-raw-pointer
+ * Values: <uint>
+ *
+ * Request backend to report raw unscaled absolute pointer coordinates.
+ * This option is only valid if request-abs-pointer is also set.
+ * Raw unscaled coordinates have the range [0, 0x7fff]
+ *
+ *----------------------- Request Transport Parameters -----------------------
+ *
+ * event-channel
+ * Values: <uint>
+ *
+ * The identifier of the Xen event channel used to signal activity
+ * in the ring buffer.
+ *
+ * page-gref
+ * Values: <uint>
+ *
+ * The Xen grant reference granting permission for the backend to map
+ * a sole page in a single page sized event ring buffer.
+ *
+ * page-ref
+ * Values: <uint>
+ *
+ * OBSOLETE, not recommended for use.
+ * PFN of the shared page.
+ */
+
+/*
+ * EVENT CODES.
+ */
+
+#define XENKBD_TYPE_MOTION 1
+#define XENKBD_TYPE_RESERVED 2
+#define XENKBD_TYPE_KEY 3
+#define XENKBD_TYPE_POS 4
+#define XENKBD_TYPE_MTOUCH 5
+
+/* Multi-touch event sub-codes */
+
+#define XENKBD_MT_EV_DOWN 0
+#define XENKBD_MT_EV_UP 1
+#define XENKBD_MT_EV_MOTION 2
+#define XENKBD_MT_EV_SYN 3
+#define XENKBD_MT_EV_SHAPE 4
+#define XENKBD_MT_EV_ORIENT 5
+
+/*
+ * CONSTANTS, XENSTORE FIELD AND PATH NAME STRINGS, HELPERS.
+ */
+
+#define XENKBD_DRIVER_NAME "vkbd"
+
+#define XENKBD_FIELD_FEAT_DSBL_KEYBRD "feature-disable-keyboard"
+#define XENKBD_FIELD_FEAT_DSBL_POINTER "feature-disable-pointer"
+#define XENKBD_FIELD_FEAT_ABS_POINTER "feature-abs-pointer"
+#define XENKBD_FIELD_FEAT_RAW_POINTER "feature-raw-pointer"
+#define XENKBD_FIELD_FEAT_MTOUCH "feature-multi-touch"
+#define XENKBD_FIELD_REQ_ABS_POINTER "request-abs-pointer"
+#define XENKBD_FIELD_REQ_RAW_POINTER "request-raw-pointer"
+#define XENKBD_FIELD_REQ_MTOUCH "request-multi-touch"
+#define XENKBD_FIELD_RING_GREF "page-gref"
+#define XENKBD_FIELD_EVT_CHANNEL "event-channel"
+#define XENKBD_FIELD_WIDTH "width"
+#define XENKBD_FIELD_HEIGHT "height"
+#define XENKBD_FIELD_MT_WIDTH "multi-touch-width"
+#define XENKBD_FIELD_MT_HEIGHT "multi-touch-height"
+#define XENKBD_FIELD_MT_NUM_CONTACTS "multi-touch-num-contacts"
+#define XENKBD_FIELD_UNIQUE_ID "unique-id"
+
+/* OBSOLETE, not recommended for use */
+#define XENKBD_FIELD_RING_REF "page-ref"
+
+/*
+ *****************************************************************************
+ * Description of the protocol between frontend and backend driver.
+ *****************************************************************************
+ *
+ * The two halves of a Para-virtual driver communicate with
+ * each other using a shared page and an event channel.
+ * Shared page contains a ring with event structures.
+ *
+ * All reserved fields in the structures below must be 0.
+ *
+ *****************************************************************************
+ * Backend to frontend events
+ *****************************************************************************
+ *
+ * Frontends should ignore unknown in events.
+ * All event packets have the same length (40 octets)
+ * All event packets have common header:
+ *
+ * 0 octet
+ * +-----------------+
+ * | type |
+ * +-----------------+
+ * type - uint8_t, event code, XENKBD_TYPE_???
+ *
+ *
+ * Pointer relative movement event
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MOTION | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | rel_x | 8
+ * +----------------+----------------+----------------+----------------+
+ * | rel_y | 12
+ * +----------------+----------------+----------------+----------------+
+ * | rel_z | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * rel_x - int32_t, relative X motion
+ * rel_y - int32_t, relative Y motion
+ * rel_z - int32_t, relative Z motion (wheel)
+ */
+
+struct xenkbd_motion {
+ uint8_t type;
+ int32_t rel_x;
+ int32_t rel_y;
+ int32_t rel_z;
+};
+
+/*
+ * Key event (includes pointer buttons)
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_KEY | pressed | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | keycode | 8
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 12
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * pressed - uint8_t, 1 if pressed; 0 otherwise
+ * keycode - uint32_t, KEY_* from linux/input.h
+ */
+
+struct xenkbd_key {
+ uint8_t type;
+ uint8_t pressed;
+ uint32_t keycode;
+};
+
+/*
+ * Pointer absolute position event
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_POS | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | abs_x | 8
+ * +----------------+----------------+----------------+----------------+
+ * | abs_y | 12
+ * +----------------+----------------+----------------+----------------+
+ * | rel_z | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * abs_x - int32_t, absolute X position (in FB pixels)
+ * abs_y - int32_t, absolute Y position (in FB pixels)
+ * rel_z - int32_t, relative Z motion (wheel)
+ */
+
+struct xenkbd_position {
+ uint8_t type;
+ int32_t abs_x;
+ int32_t abs_y;
+ int32_t rel_z;
+};
+
+/*
+ * Multi-touch event and its sub-types
+ *
+ * All multi-touch event packets have common header:
+ *
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | event_type | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ *
+ * event_type - unt8_t, multi-touch event sub-type, XENKBD_MT_EV_???
+ * contact_id - unt8_t, ID of the contact
+ *
+ * Touch interactions can consist of one or more contacts.
+ * For each contact, a series of events is generated, starting
+ * with a down event, followed by zero or more motion events,
+ * and ending with an up event. Events relating to the same
+ * contact point can be identified by the ID of the sequence: contact ID.
+ * Contact ID may be reused after XENKBD_MT_EV_UP event and
+ * is in the [0; XENKBD_FIELD_NUM_CONTACTS - 1] range.
+ *
+ * For further information please refer to documentation on Wayland [1],
+ * Linux [2] and Windows [3] multi-touch support.
+ *
+ * [1] https://cgit.freedesktop.org/wayland/wayland/tree/protocol/wayland.xml
+ * [2] https://www.kernel.org/doc/Documentation/input/multi-touch-protocol.rst
+ * [3] https://msdn.microsoft.com/en-us/library/jj151564(v=vs.85).aspx
+ *
+ *
+ * Multi-touch down event - sent when a new touch is made: touch is assigned
+ * a unique contact ID, sent with this and consequent events related
+ * to this touch.
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | _MT_EV_DOWN | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | abs_x | 12
+ * +----------------+----------------+----------------+----------------+
+ * | abs_y | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * abs_x - int32_t, absolute X position, in pixels
+ * abs_y - int32_t, absolute Y position, in pixels
+ *
+ * Multi-touch contact release event
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | _MT_EV_UP | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * Multi-touch motion event
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | _MT_EV_MOTION | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | abs_x | 12
+ * +----------------+----------------+----------------+----------------+
+ * | abs_y | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * abs_x - int32_t, absolute X position, in pixels,
+ * abs_y - int32_t, absolute Y position, in pixels,
+ *
+ * Multi-touch input synchronization event - shows end of a set of events
+ * which logically belong together.
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | _MT_EV_SYN | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * Multi-touch shape event - touch point's shape has changed its shape.
+ * Shape is approximated by an ellipse through the major and minor axis
+ * lengths: major is the longer diameter of the ellipse and minor is the
+ * shorter one. Center of the ellipse is reported via
+ * XENKBD_MT_EV_DOWN/XENKBD_MT_EV_MOTION events.
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | _MT_EV_SHAPE | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | major | 12
+ * +----------------+----------------+----------------+----------------+
+ * | minor | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * major - unt32_t, length of the major axis, pixels
+ * minor - unt32_t, length of the minor axis, pixels
+ *
+ * Multi-touch orientation event - touch point's shape has changed
+ * its orientation: calculated as a clockwise angle between the major axis
+ * of the ellipse and positive Y axis in degrees, [-180; +180].
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | _TYPE_MTOUCH | _MT_EV_ORIENT | contact_id | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | orientation | reserved | 12
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 16
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 40
+ * +----------------+----------------+----------------+----------------+
+ *
+ * orientation - int16_t, clockwise angle of the major axis
+ */
+
+struct xenkbd_mtouch {
+ uint8_t type; /* XENKBD_TYPE_MTOUCH */
+ uint8_t event_type; /* XENKBD_MT_EV_??? */
+ uint8_t contact_id;
+ uint8_t reserved[5]; /* reserved for the future use */
+ union {
+ struct {
+ int32_t abs_x; /* absolute X position, pixels */
+ int32_t abs_y; /* absolute Y position, pixels */
+ } pos;
+ struct {
+ uint32_t major; /* length of the major axis, pixels */
+ uint32_t minor; /* length of the minor axis, pixels */
+ } shape;
+ int16_t orientation; /* clockwise angle of the major axis */
+ } u;
+};
+
+#define XENKBD_IN_EVENT_SIZE 40
+
+union xenkbd_in_event {
+ uint8_t type;
+ struct xenkbd_motion motion;
+ struct xenkbd_key key;
+ struct xenkbd_position pos;
+ struct xenkbd_mtouch mtouch;
+ char pad[XENKBD_IN_EVENT_SIZE];
+};
+
+/*
+ *****************************************************************************
+ * Frontend to backend events
+ *****************************************************************************
+ *
+ * Out events may be sent only when requested by backend, and receipt
+ * of an unknown out event is an error.
+ * No out events currently defined.
+
+ * All event packets have the same length (40 octets)
+ * All event packets have common header:
+ * 0 octet
+ * +-----------------+
+ * | type |
+ * +-----------------+
+ * type - uint8_t, event code
+ */
+
+#define XENKBD_OUT_EVENT_SIZE 40
+
+union xenkbd_out_event {
+ uint8_t type;
+ char pad[XENKBD_OUT_EVENT_SIZE];
+};
+
+/*
+ *****************************************************************************
+ * Shared page
+ *****************************************************************************
+ */
+
+#define XENKBD_IN_RING_SIZE 2048
+#define XENKBD_IN_RING_LEN (XENKBD_IN_RING_SIZE / XENKBD_IN_EVENT_SIZE)
+#define XENKBD_IN_RING_OFFS 1024
+#define XENKBD_IN_RING(page) \
+ ((union xenkbd_in_event *)((char *)(page) + XENKBD_IN_RING_OFFS))
+#define XENKBD_IN_RING_REF(page, idx) \
+ (XENKBD_IN_RING((page))[(idx) % XENKBD_IN_RING_LEN])
+
+#define XENKBD_OUT_RING_SIZE 1024
+#define XENKBD_OUT_RING_LEN (XENKBD_OUT_RING_SIZE / XENKBD_OUT_EVENT_SIZE)
+#define XENKBD_OUT_RING_OFFS (XENKBD_IN_RING_OFFS + XENKBD_IN_RING_SIZE)
+#define XENKBD_OUT_RING(page) \
+ ((union xenkbd_out_event *)((char *)(page) + XENKBD_OUT_RING_OFFS))
+#define XENKBD_OUT_RING_REF(page, idx) \
+ (XENKBD_OUT_RING((page))[(idx) % XENKBD_OUT_RING_LEN])
+
+struct xenkbd_page {
+ uint32_t in_cons, in_prod;
+ uint32_t out_cons, out_prod;
+};
+
+#endif /* __XEN_PUBLIC_IO_KBDIF_H__ */
diff --git a/include/xen/interface/io/netif.h b/include/xen/interface/io/netif.h
new file mode 100644
index 000000000..2194322c3
--- /dev/null
+++ b/include/xen/interface/io/netif.h
@@ -0,0 +1,957 @@
+/******************************************************************************
+ * xen_netif.h
+ *
+ * Unified network-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) 2003-2004, Keir Fraser
+ */
+
+#ifndef __XEN_PUBLIC_IO_XEN_NETIF_H__
+#define __XEN_PUBLIC_IO_XEN_NETIF_H__
+
+#include "ring.h"
+#include "../grant_table.h"
+
+/*
+ * Older implementation of Xen network frontend / backend has an
+ * implicit dependency on the MAX_SKB_FRAGS as the maximum number of
+ * ring slots a skb can use. Netfront / netback may not work as
+ * expected when frontend and backend have different MAX_SKB_FRAGS.
+ *
+ * A better approach is to add mechanism for netfront / netback to
+ * negotiate this value. However we cannot fix all possible
+ * frontends, so we need to define a value which states the minimum
+ * slots backend must support.
+ *
+ * The minimum value derives from older Linux kernel's MAX_SKB_FRAGS
+ * (18), which is proved to work with most frontends. Any new backend
+ * which doesn't negotiate with frontend should expect frontend to
+ * send a valid packet using slots up to this value.
+ */
+#define XEN_NETIF_NR_SLOTS_MIN 18
+
+/*
+ * Notifications after enqueuing any type of message should be conditional on
+ * the appropriate req_event or rsp_event field in the shared ring.
+ * If the client sends notification for rx requests then it should specify
+ * feature 'feature-rx-notify' via xenbus. Otherwise the backend will assume
+ * that it cannot safely queue packets (as it may not be kicked to send them).
+ */
+
+/*
+ * "feature-split-event-channels" is introduced to separate guest TX
+ * and RX notification. Backend either doesn't support this feature or
+ * advertises it via xenstore as 0 (disabled) or 1 (enabled).
+ *
+ * To make use of this feature, frontend should allocate two event
+ * channels for TX and RX, advertise them to backend as
+ * "event-channel-tx" and "event-channel-rx" respectively. If frontend
+ * doesn't want to use this feature, it just writes "event-channel"
+ * node as before.
+ */
+
+/*
+ * Multiple transmit and receive queues:
+ * If supported, the backend will write the key "multi-queue-max-queues" to
+ * the directory for that vif, and set its value to the maximum supported
+ * number of queues.
+ * Frontends that are aware of this feature and wish to use it can write the
+ * key "multi-queue-num-queues", set to the number they wish to use, which
+ * must be greater than zero, and no more than the value reported by the backend
+ * in "multi-queue-max-queues".
+ *
+ * Queues replicate the shared rings and event channels.
+ * "feature-split-event-channels" may optionally be used when using
+ * multiple queues, but is not mandatory.
+ *
+ * Each queue consists of one shared ring pair, i.e. there must be the same
+ * number of tx and rx rings.
+ *
+ * For frontends requesting just one queue, the usual event-channel and
+ * ring-ref keys are written as before, simplifying the backend processing
+ * to avoid distinguishing between a frontend that doesn't understand the
+ * multi-queue feature, and one that does, but requested only one queue.
+ *
+ * Frontends requesting two or more queues must not write the toplevel
+ * event-channel (or event-channel-{tx,rx}) and {tx,rx}-ring-ref keys,
+ * instead writing those keys under sub-keys having the name "queue-N" where
+ * N is the integer ID of the queue for which those keys belong. Queues
+ * are indexed from zero. For example, a frontend with two queues and split
+ * event channels must write the following set of queue-related keys:
+ *
+ * /local/domain/1/device/vif/0/multi-queue-num-queues = "2"
+ * /local/domain/1/device/vif/0/queue-0 = ""
+ * /local/domain/1/device/vif/0/queue-0/tx-ring-ref = "<ring-ref-tx0>"
+ * /local/domain/1/device/vif/0/queue-0/rx-ring-ref = "<ring-ref-rx0>"
+ * /local/domain/1/device/vif/0/queue-0/event-channel-tx = "<evtchn-tx0>"
+ * /local/domain/1/device/vif/0/queue-0/event-channel-rx = "<evtchn-rx0>"
+ * /local/domain/1/device/vif/0/queue-1 = ""
+ * /local/domain/1/device/vif/0/queue-1/tx-ring-ref = "<ring-ref-tx1>"
+ * /local/domain/1/device/vif/0/queue-1/rx-ring-ref = "<ring-ref-rx1"
+ * /local/domain/1/device/vif/0/queue-1/event-channel-tx = "<evtchn-tx1>"
+ * /local/domain/1/device/vif/0/queue-1/event-channel-rx = "<evtchn-rx1>"
+ *
+ * If there is any inconsistency in the XenStore data, the backend may
+ * choose not to connect any queues, instead treating the request as an
+ * error. This includes scenarios where more (or fewer) queues were
+ * requested than the frontend provided details for.
+ *
+ * Mapping of packets to queues is considered to be a function of the
+ * transmitting system (backend or frontend) and is not negotiated
+ * between the two. Guests are free to transmit packets on any queue
+ * they choose, provided it has been set up correctly. Guests must be
+ * prepared to receive packets on any queue they have requested be set up.
+ */
+
+/*
+ * "feature-no-csum-offload" should be used to turn IPv4 TCP/UDP checksum
+ * offload off or on. If it is missing then the feature is assumed to be on.
+ * "feature-ipv6-csum-offload" should be used to turn IPv6 TCP/UDP checksum
+ * offload on or off. If it is missing then the feature is assumed to be off.
+ */
+
+/*
+ * "feature-gso-tcpv4" and "feature-gso-tcpv6" advertise the capability to
+ * handle large TCP packets (in IPv4 or IPv6 form respectively). Neither
+ * frontends nor backends are assumed to be capable unless the flags are
+ * present.
+ */
+
+/*
+ * "feature-multicast-control" and "feature-dynamic-multicast-control"
+ * advertise the capability to filter ethernet multicast packets in the
+ * backend. If the frontend wishes to take advantage of this feature then
+ * it may set "request-multicast-control". If the backend only advertises
+ * "feature-multicast-control" then "request-multicast-control" must be set
+ * before the frontend moves into the connected state. The backend will
+ * sample the value on this state transition and any subsequent change in
+ * value will have no effect. However, if the backend also advertises
+ * "feature-dynamic-multicast-control" then "request-multicast-control"
+ * may be set by the frontend at any time. In this case, the backend will
+ * watch the value and re-sample on watch events.
+ *
+ * If the sampled value of "request-multicast-control" is set then the
+ * backend transmit side should no longer flood multicast packets to the
+ * frontend, it should instead drop any multicast packet that does not
+ * match in a filter list.
+ * The list is amended by the frontend by sending dummy transmit requests
+ * containing XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL} extra-info fragments as
+ * specified below.
+ * Note that the filter list may be amended even if the sampled value of
+ * "request-multicast-control" is not set, however the filter should only
+ * be applied if it is set.
+ */
+
+/*
+ * "xdp-headroom" is used to request that extra space is added
+ * for XDP processing. The value is measured in bytes and passed by
+ * the frontend to be consistent between both ends.
+ * If the value is greater than zero that means that
+ * an RX response is going to be passed to an XDP program for processing.
+ * XEN_NETIF_MAX_XDP_HEADROOM defines the maximum headroom offset in bytes
+ *
+ * "feature-xdp-headroom" is set to "1" by the netback side like other features
+ * so a guest can check if an XDP program can be processed.
+ */
+#define XEN_NETIF_MAX_XDP_HEADROOM 0x7FFF
+
+/*
+ * Control ring
+ * ============
+ *
+ * Some features, such as hashing (detailed below), require a
+ * significant amount of out-of-band data to be passed from frontend to
+ * backend. Use of xenstore is not suitable for large quantities of data
+ * because of quota limitations and so a dedicated 'control ring' is used.
+ * The ability of the backend to use a control ring is advertised by
+ * setting:
+ *
+ * /local/domain/X/backend/<domid>/<vif>/feature-ctrl-ring = "1"
+ *
+ * The frontend provides a control ring to the backend by setting:
+ *
+ * /local/domain/<domid>/device/vif/<vif>/ctrl-ring-ref = <gref>
+ * /local/domain/<domid>/device/vif/<vif>/event-channel-ctrl = <port>
+ *
+ * where <gref> is the grant reference of the shared page used to
+ * implement the control ring and <port> is an event channel to be used
+ * as a mailbox interrupt. These keys must be set before the frontend
+ * moves into the connected state.
+ *
+ * The control ring uses a fixed request/response message size and is
+ * balanced (i.e. one request to one response), so operationally it is much
+ * the same as a transmit or receive ring.
+ * Note that there is no requirement that responses are issued in the same
+ * order as requests.
+ */
+
+/*
+ * Hash types
+ * ==========
+ *
+ * For the purposes of the definitions below, 'Packet[]' is an array of
+ * octets containing an IP packet without options, 'Array[X..Y]' means a
+ * sub-array of 'Array' containing bytes X thru Y inclusive, and '+' is
+ * used to indicate concatenation of arrays.
+ */
+
+/*
+ * A hash calculated over an IP version 4 header as follows:
+ *
+ * Buffer[0..8] = Packet[12..15] (source address) +
+ * Packet[16..19] (destination address)
+ *
+ * Result = Hash(Buffer, 8)
+ */
+#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4 0
+#define XEN_NETIF_CTRL_HASH_TYPE_IPV4 \
+ (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4)
+
+/*
+ * A hash calculated over an IP version 4 header and TCP header as
+ * follows:
+ *
+ * Buffer[0..12] = Packet[12..15] (source address) +
+ * Packet[16..19] (destination address) +
+ * Packet[20..21] (source port) +
+ * Packet[22..23] (destination port)
+ *
+ * Result = Hash(Buffer, 12)
+ */
+#define _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP 1
+#define XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP \
+ (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV4_TCP)
+
+/*
+ * A hash calculated over an IP version 6 header as follows:
+ *
+ * Buffer[0..32] = Packet[8..23] (source address ) +
+ * Packet[24..39] (destination address)
+ *
+ * Result = Hash(Buffer, 32)
+ */
+#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6 2
+#define XEN_NETIF_CTRL_HASH_TYPE_IPV6 \
+ (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6)
+
+/*
+ * A hash calculated over an IP version 6 header and TCP header as
+ * follows:
+ *
+ * Buffer[0..36] = Packet[8..23] (source address) +
+ * Packet[24..39] (destination address) +
+ * Packet[40..41] (source port) +
+ * Packet[42..43] (destination port)
+ *
+ * Result = Hash(Buffer, 36)
+ */
+#define _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP 3
+#define XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP \
+ (1 << _XEN_NETIF_CTRL_HASH_TYPE_IPV6_TCP)
+
+/*
+ * Hash algorithms
+ * ===============
+ */
+
+#define XEN_NETIF_CTRL_HASH_ALGORITHM_NONE 0
+
+/*
+ * Toeplitz hash:
+ */
+
+#define XEN_NETIF_CTRL_HASH_ALGORITHM_TOEPLITZ 1
+
+/*
+ * This algorithm uses a 'key' as well as the data buffer itself.
+ * (Buffer[] and Key[] are treated as shift-registers where the MSB of
+ * Buffer/Key[0] is considered 'left-most' and the LSB of Buffer/Key[N-1]
+ * is the 'right-most').
+ *
+ * Value = 0
+ * For number of bits in Buffer[]
+ * If (left-most bit of Buffer[] is 1)
+ * Value ^= left-most 32 bits of Key[]
+ * Key[] << 1
+ * Buffer[] << 1
+ *
+ * The code below is provided for convenience where an operating system
+ * does not already provide an implementation.
+ */
+#ifdef XEN_NETIF_DEFINE_TOEPLITZ
+static uint32_t xen_netif_toeplitz_hash(const uint8_t *key,
+ unsigned int keylen,
+ const uint8_t *buf, unsigned int buflen)
+{
+ unsigned int keyi, bufi;
+ uint64_t prefix = 0;
+ uint64_t hash = 0;
+
+ /* Pre-load prefix with the first 8 bytes of the key */
+ for (keyi = 0; keyi < 8; keyi++) {
+ prefix <<= 8;
+ prefix |= (keyi < keylen) ? key[keyi] : 0;
+ }
+
+ for (bufi = 0; bufi < buflen; bufi++) {
+ uint8_t byte = buf[bufi];
+ unsigned int bit;
+
+ for (bit = 0; bit < 8; bit++) {
+ if (byte & 0x80)
+ hash ^= prefix;
+ prefix <<= 1;
+ byte <<= 1;
+ }
+
+ /*
+ * 'prefix' has now been left-shifted by 8, so
+ * OR in the next byte.
+ */
+ prefix |= (keyi < keylen) ? key[keyi] : 0;
+ keyi++;
+ }
+
+ /* The valid part of the hash is in the upper 32 bits. */
+ return hash >> 32;
+}
+#endif /* XEN_NETIF_DEFINE_TOEPLITZ */
+
+/*
+ * Control requests (struct xen_netif_ctrl_request)
+ * ================================================
+ *
+ * All requests have the following format:
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | id | type | data[0] |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | data[1] | data[2] |
+ * +-----+-----+-----+-----+-----------------------+
+ *
+ * id: the request identifier, echoed in response.
+ * type: the type of request (see below)
+ * data[]: any data associated with the request (determined by type)
+ */
+
+struct xen_netif_ctrl_request {
+ uint16_t id;
+ uint16_t type;
+
+#define XEN_NETIF_CTRL_TYPE_INVALID 0
+#define XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS 1
+#define XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS 2
+#define XEN_NETIF_CTRL_TYPE_SET_HASH_KEY 3
+#define XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE 4
+#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE 5
+#define XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING 6
+#define XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM 7
+
+ uint32_t data[3];
+};
+
+/*
+ * Control responses (struct xen_netif_ctrl_response)
+ * ==================================================
+ *
+ * All responses have the following format:
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | id | type | status |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | data |
+ * +-----+-----+-----+-----+
+ *
+ * id: the corresponding request identifier
+ * type: the type of the corresponding request
+ * status: the status of request processing
+ * data: any data associated with the response (determined by type and
+ * status)
+ */
+
+struct xen_netif_ctrl_response {
+ uint16_t id;
+ uint16_t type;
+ uint32_t status;
+
+#define XEN_NETIF_CTRL_STATUS_SUCCESS 0
+#define XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED 1
+#define XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER 2
+#define XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW 3
+
+ uint32_t data;
+};
+
+/*
+ * Control messages
+ * ================
+ *
+ * XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM
+ * --------------------------------------
+ *
+ * This is sent by the frontend to set the desired hash algorithm.
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_SET_HASH_ALGORITHM
+ * data[0] = a XEN_NETIF_CTRL_HASH_ALGORITHM_* value
+ * data[1] = 0
+ * data[2] = 0
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not
+ * supported
+ * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - The algorithm is not
+ * supported
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ *
+ * NOTE: Setting data[0] to XEN_NETIF_CTRL_HASH_ALGORITHM_NONE disables
+ * hashing and the backend is free to choose how it steers packets
+ * to queues (which is the default behaviour).
+ *
+ * XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS
+ * ----------------------------------
+ *
+ * This is sent by the frontend to query the types of hash supported by
+ * the backend.
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_GET_HASH_FLAGS
+ * data[0] = 0
+ * data[1] = 0
+ * data[2] = 0
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ * data = supported hash types (if operation was successful)
+ *
+ * NOTE: A valid hash algorithm must be selected before this operation can
+ * succeed.
+ *
+ * XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS
+ * ----------------------------------
+ *
+ * This is sent by the frontend to set the types of hash that the backend
+ * should calculate. (See above for hash type definitions).
+ * Note that the 'maximal' type of hash should always be chosen. For
+ * example, if the frontend sets both IPV4 and IPV4_TCP hash types then
+ * the latter hash type should be calculated for any TCP packet and the
+ * former only calculated for non-TCP packets.
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_SET_HASH_FLAGS
+ * data[0] = bitwise OR of XEN_NETIF_CTRL_HASH_TYPE_* values
+ * data[1] = 0
+ * data[2] = 0
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not
+ * supported
+ * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - One or more flag
+ * value is invalid or
+ * unsupported
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ * data = 0
+ *
+ * NOTE: A valid hash algorithm must be selected before this operation can
+ * succeed.
+ * Also, setting data[0] to zero disables hashing and the backend
+ * is free to choose how it steers packets to queues.
+ *
+ * XEN_NETIF_CTRL_TYPE_SET_HASH_KEY
+ * --------------------------------
+ *
+ * This is sent by the frontend to set the key of the hash if the algorithm
+ * requires it. (See hash algorithms above).
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_SET_HASH_KEY
+ * data[0] = grant reference of page containing the key (assumed to
+ * start at beginning of grant)
+ * data[1] = size of key in octets
+ * data[2] = 0
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not
+ * supported
+ * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Key size is invalid
+ * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Key size is larger
+ * than the backend
+ * supports
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ * data = 0
+ *
+ * NOTE: Any key octets not specified are assumed to be zero (the key
+ * is assumed to be empty by default) and specifying a new key
+ * invalidates any previous key, hence specifying a key size of
+ * zero will clear the key (which ensures that the calculated hash
+ * will always be zero).
+ * The maximum size of key is algorithm and backend specific, but
+ * is also limited by the single grant reference.
+ * The grant reference may be read-only and must remain valid until
+ * the response has been processed.
+ *
+ * XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE
+ * -----------------------------------------
+ *
+ * This is sent by the frontend to query the maximum size of mapping
+ * table supported by the backend. The size is specified in terms of
+ * table entries.
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_GET_HASH_MAPPING_SIZE
+ * data[0] = 0
+ * data[1] = 0
+ * data[2] = 0
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not supported
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ * data = maximum number of entries allowed in the mapping table
+ * (if operation was successful) or zero if a mapping table is
+ * not supported (i.e. hash mapping is done only by modular
+ * arithmetic).
+ *
+ * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE
+ * -------------------------------------
+ *
+ * This is sent by the frontend to set the actual size of the mapping
+ * table to be used by the backend. The size is specified in terms of
+ * table entries.
+ * Any previous table is invalidated by this message and any new table
+ * is assumed to be zero filled.
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE
+ * data[0] = number of entries in mapping table
+ * data[1] = 0
+ * data[2] = 0
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not
+ * supported
+ * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size is invalid
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ * data = 0
+ *
+ * NOTE: Setting data[0] to 0 means that hash mapping should be done
+ * using modular arithmetic.
+ *
+ * XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING
+ * ------------------------------------
+ *
+ * This is sent by the frontend to set the content of the table mapping
+ * hash value to queue number. The backend should calculate the hash from
+ * the packet header, use it as an index into the table (modulo the size
+ * of the table) and then steer the packet to the queue number found at
+ * that index.
+ *
+ * Request:
+ *
+ * type = XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING
+ * data[0] = grant reference of page containing the mapping (sub-)table
+ * (assumed to start at beginning of grant)
+ * data[1] = size of (sub-)table in entries
+ * data[2] = offset, in entries, of sub-table within overall table
+ *
+ * Response:
+ *
+ * status = XEN_NETIF_CTRL_STATUS_NOT_SUPPORTED - Operation not
+ * supported
+ * XEN_NETIF_CTRL_STATUS_INVALID_PARAMETER - Table size or content
+ * is invalid
+ * XEN_NETIF_CTRL_STATUS_BUFFER_OVERFLOW - Table size is larger
+ * than the backend
+ * supports
+ * XEN_NETIF_CTRL_STATUS_SUCCESS - Operation successful
+ * data = 0
+ *
+ * NOTE: The overall table has the following format:
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | mapping[0] | mapping[1] |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | . |
+ * | . |
+ * | . |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | mapping[N-2] | mapping[N-1] |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ *
+ * where N is specified by a XEN_NETIF_CTRL_TYPE_SET_HASH_MAPPING_SIZE
+ * message and each mapping must specifies a queue between 0 and
+ * "multi-queue-num-queues" (see above).
+ * The backend may support a mapping table larger than can be
+ * mapped by a single grant reference. Thus sub-tables within a
+ * larger table can be individually set by sending multiple messages
+ * with differing offset values. Specifying a new sub-table does not
+ * invalidate any table data outside that range.
+ * The grant reference may be read-only and must remain valid until
+ * the response has been processed.
+ */
+
+DEFINE_RING_TYPES(xen_netif_ctrl,
+ struct xen_netif_ctrl_request,
+ struct xen_netif_ctrl_response);
+
+/*
+ * Guest transmit
+ * ==============
+ *
+ * This is the 'wire' format for transmit (frontend -> backend) packets:
+ *
+ * Fragment 1: xen_netif_tx_request_t - flags = XEN_NETTXF_*
+ * size = total packet size
+ * [Extra 1: xen_netif_extra_info_t] - (only if fragment 1 flags include
+ * XEN_NETTXF_extra_info)
+ * ...
+ * [Extra N: xen_netif_extra_info_t] - (only if extra N-1 flags include
+ * XEN_NETIF_EXTRA_MORE)
+ * ...
+ * Fragment N: xen_netif_tx_request_t - (only if fragment N-1 flags include
+ * XEN_NETTXF_more_data - flags on preceding
+ * extras are not relevant here)
+ * flags = 0
+ * size = fragment size
+ *
+ * NOTE:
+ *
+ * This format slightly is different from that used for receive
+ * (backend -> frontend) packets. Specifically, in a multi-fragment
+ * packet the actual size of fragment 1 can only be determined by
+ * subtracting the sizes of fragments 2..N from the total packet size.
+ *
+ * Ring slot size is 12 octets, however not all request/response
+ * structs use the full size.
+ *
+ * tx request data (xen_netif_tx_request_t)
+ * ------------------------------------
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | grant ref | offset | flags |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | id | size |
+ * +-----+-----+-----+-----+
+ *
+ * grant ref: Reference to buffer page.
+ * offset: Offset within buffer page.
+ * flags: XEN_NETTXF_*.
+ * id: request identifier, echoed in response.
+ * size: packet size in bytes.
+ *
+ * tx response (xen_netif_tx_response_t)
+ * ---------------------------------
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | id | status | unused |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | unused |
+ * +-----+-----+-----+-----+
+ *
+ * id: reflects id in transmit request
+ * status: XEN_NETIF_RSP_*
+ *
+ * Guest receive
+ * =============
+ *
+ * This is the 'wire' format for receive (backend -> frontend) packets:
+ *
+ * Fragment 1: xen_netif_rx_request_t - flags = XEN_NETRXF_*
+ * size = fragment size
+ * [Extra 1: xen_netif_extra_info_t] - (only if fragment 1 flags include
+ * XEN_NETRXF_extra_info)
+ * ...
+ * [Extra N: xen_netif_extra_info_t] - (only if extra N-1 flags include
+ * XEN_NETIF_EXTRA_MORE)
+ * ...
+ * Fragment N: xen_netif_rx_request_t - (only if fragment N-1 flags include
+ * XEN_NETRXF_more_data - flags on preceding
+ * extras are not relevant here)
+ * flags = 0
+ * size = fragment size
+ *
+ * NOTE:
+ *
+ * This format slightly is different from that used for transmit
+ * (frontend -> backend) packets. Specifically, in a multi-fragment
+ * packet the size of the packet can only be determined by summing the
+ * sizes of fragments 1..N.
+ *
+ * Ring slot size is 8 octets.
+ *
+ * rx request (xen_netif_rx_request_t)
+ * -------------------------------
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | id | pad | gref |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ *
+ * id: request identifier, echoed in response.
+ * gref: reference to incoming granted frame.
+ *
+ * rx response (xen_netif_rx_response_t)
+ * ---------------------------------
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | id | offset | flags | status |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ *
+ * id: reflects id in receive request
+ * offset: offset in page of start of received packet
+ * flags: XEN_NETRXF_*
+ * status: -ve: XEN_NETIF_RSP_*; +ve: Rx'ed pkt size.
+ *
+ * NOTE: Historically, to support GSO on the frontend receive side, Linux
+ * netfront does not make use of the rx response id (because, as
+ * described below, extra info structures overlay the id field).
+ * Instead it assumes that responses always appear in the same ring
+ * slot as their corresponding request. Thus, to maintain
+ * compatibility, backends must make sure this is the case.
+ *
+ * Extra Info
+ * ==========
+ *
+ * Can be present if initial request or response has NET{T,R}XF_extra_info,
+ * or previous extra request has XEN_NETIF_EXTRA_MORE.
+ *
+ * The struct therefore needs to fit into either a tx or rx slot and
+ * is therefore limited to 8 octets.
+ *
+ * NOTE: Because extra info data overlays the usual request/response
+ * structures, there is no id information in the opposite direction.
+ * So, if an extra info overlays an rx response the frontend can
+ * assume that it is in the same ring slot as the request that was
+ * consumed to make the slot available, and the backend must ensure
+ * this assumption is true.
+ *
+ * extra info (xen_netif_extra_info_t)
+ * -------------------------------
+ *
+ * General format:
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * |type |flags| type specific data |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * | padding for tx |
+ * +-----+-----+-----+-----+
+ *
+ * type: XEN_NETIF_EXTRA_TYPE_*
+ * flags: XEN_NETIF_EXTRA_FLAG_*
+ * padding for tx: present only in the tx case due to 8 octet limit
+ * from rx case. Not shown in type specific entries
+ * below.
+ *
+ * XEN_NETIF_EXTRA_TYPE_GSO:
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * |type |flags| size |type | pad | features |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ *
+ * type: Must be XEN_NETIF_EXTRA_TYPE_GSO
+ * flags: XEN_NETIF_EXTRA_FLAG_*
+ * size: Maximum payload size of each segment. For example,
+ * for TCP this is just the path MSS.
+ * type: XEN_NETIF_GSO_TYPE_*: This determines the protocol of
+ * the packet and any extra features required to segment the
+ * packet properly.
+ * features: EN_XEN_NETIF_GSO_FEAT_*: This specifies any extra GSO
+ * features required to process this packet, such as ECN
+ * support for TCPv4.
+ *
+ * XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL}:
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * |type |flags| addr |
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ *
+ * type: Must be XEN_NETIF_EXTRA_TYPE_MCAST_{ADD,DEL}
+ * flags: XEN_NETIF_EXTRA_FLAG_*
+ * addr: address to add/remove
+ *
+ * XEN_NETIF_EXTRA_TYPE_HASH:
+ *
+ * A backend that supports teoplitz hashing is assumed to accept
+ * this type of extra info in transmit packets.
+ * A frontend that enables hashing is assumed to accept
+ * this type of extra info in receive packets.
+ *
+ * 0 1 2 3 4 5 6 7 octet
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ * |type |flags|htype| alg |LSB ---- value ---- MSB|
+ * +-----+-----+-----+-----+-----+-----+-----+-----+
+ *
+ * type: Must be XEN_NETIF_EXTRA_TYPE_HASH
+ * flags: XEN_NETIF_EXTRA_FLAG_*
+ * htype: Hash type (one of _XEN_NETIF_CTRL_HASH_TYPE_* - see above)
+ * alg: The algorithm used to calculate the hash (one of
+ * XEN_NETIF_CTRL_HASH_TYPE_ALGORITHM_* - see above)
+ * value: Hash value
+ */
+
+/* Protocol checksum field is blank in the packet (hardware offload)? */
+#define _XEN_NETTXF_csum_blank (0)
+#define XEN_NETTXF_csum_blank (1U<<_XEN_NETTXF_csum_blank)
+
+/* Packet data has been validated against protocol checksum. */
+#define _XEN_NETTXF_data_validated (1)
+#define XEN_NETTXF_data_validated (1U<<_XEN_NETTXF_data_validated)
+
+/* Packet continues in the next request descriptor. */
+#define _XEN_NETTXF_more_data (2)
+#define XEN_NETTXF_more_data (1U<<_XEN_NETTXF_more_data)
+
+/* Packet to be followed by extra descriptor(s). */
+#define _XEN_NETTXF_extra_info (3)
+#define XEN_NETTXF_extra_info (1U<<_XEN_NETTXF_extra_info)
+
+#define XEN_NETIF_MAX_TX_SIZE 0xFFFF
+struct xen_netif_tx_request {
+ grant_ref_t gref;
+ uint16_t offset;
+ uint16_t flags;
+ uint16_t id;
+ uint16_t size;
+};
+
+/* Types of xen_netif_extra_info descriptors. */
+#define XEN_NETIF_EXTRA_TYPE_NONE (0) /* Never used - invalid */
+#define XEN_NETIF_EXTRA_TYPE_GSO (1) /* u.gso */
+#define XEN_NETIF_EXTRA_TYPE_MCAST_ADD (2) /* u.mcast */
+#define XEN_NETIF_EXTRA_TYPE_MCAST_DEL (3) /* u.mcast */
+#define XEN_NETIF_EXTRA_TYPE_HASH (4) /* u.hash */
+#define XEN_NETIF_EXTRA_TYPE_XDP (5) /* u.xdp */
+#define XEN_NETIF_EXTRA_TYPE_MAX (6)
+
+/* xen_netif_extra_info_t flags. */
+#define _XEN_NETIF_EXTRA_FLAG_MORE (0)
+#define XEN_NETIF_EXTRA_FLAG_MORE (1U<<_XEN_NETIF_EXTRA_FLAG_MORE)
+
+/* GSO types */
+#define XEN_NETIF_GSO_TYPE_NONE (0)
+#define XEN_NETIF_GSO_TYPE_TCPV4 (1)
+#define XEN_NETIF_GSO_TYPE_TCPV6 (2)
+
+/*
+ * This structure needs to fit within both xen_netif_tx_request_t and
+ * xen_netif_rx_response_t for compatibility.
+ */
+struct xen_netif_extra_info {
+ uint8_t type;
+ uint8_t flags;
+ union {
+ struct {
+ uint16_t size;
+ uint8_t type;
+ uint8_t pad;
+ uint16_t features;
+ } gso;
+ struct {
+ uint8_t addr[6];
+ } mcast;
+ struct {
+ uint8_t type;
+ uint8_t algorithm;
+ uint8_t value[4];
+ } hash;
+ struct {
+ uint16_t headroom;
+ uint16_t pad[2];
+ } xdp;
+ uint16_t pad[3];
+ } u;
+};
+
+struct xen_netif_tx_response {
+ uint16_t id;
+ int16_t status;
+};
+
+struct xen_netif_rx_request {
+ uint16_t id; /* Echoed in response message. */
+ uint16_t pad;
+ grant_ref_t gref;
+};
+
+/* Packet data has been validated against protocol checksum. */
+#define _XEN_NETRXF_data_validated (0)
+#define XEN_NETRXF_data_validated (1U<<_XEN_NETRXF_data_validated)
+
+/* Protocol checksum field is blank in the packet (hardware offload)? */
+#define _XEN_NETRXF_csum_blank (1)
+#define XEN_NETRXF_csum_blank (1U<<_XEN_NETRXF_csum_blank)
+
+/* Packet continues in the next request descriptor. */
+#define _XEN_NETRXF_more_data (2)
+#define XEN_NETRXF_more_data (1U<<_XEN_NETRXF_more_data)
+
+/* Packet to be followed by extra descriptor(s). */
+#define _XEN_NETRXF_extra_info (3)
+#define XEN_NETRXF_extra_info (1U<<_XEN_NETRXF_extra_info)
+
+/* Packet has GSO prefix. Deprecated but included for compatibility */
+#define _XEN_NETRXF_gso_prefix (4)
+#define XEN_NETRXF_gso_prefix (1U<<_XEN_NETRXF_gso_prefix)
+
+struct xen_netif_rx_response {
+ uint16_t id;
+ uint16_t offset;
+ uint16_t flags;
+ int16_t status;
+};
+
+/*
+ * Generate xen_netif ring structures and types.
+ */
+
+DEFINE_RING_TYPES(xen_netif_tx, struct xen_netif_tx_request,
+ struct xen_netif_tx_response);
+DEFINE_RING_TYPES(xen_netif_rx, struct xen_netif_rx_request,
+ struct xen_netif_rx_response);
+
+#define XEN_NETIF_RSP_DROPPED -2
+#define XEN_NETIF_RSP_ERROR -1
+#define XEN_NETIF_RSP_OKAY 0
+/* No response: used for auxiliary requests (e.g., xen_netif_extra_info_t). */
+#define XEN_NETIF_RSP_NULL 1
+
+#endif
diff --git a/include/xen/interface/io/pciif.h b/include/xen/interface/io/pciif.h
new file mode 100644
index 000000000..d9922ae36
--- /dev/null
+++ b/include/xen/interface/io/pciif.h
@@ -0,0 +1,112 @@
+/*
+ * PCI Backend/Frontend Common Data Structures & Macros
+ *
+ * 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.
+ *
+ * Author: Ryan Wilson <hap9@epoch.ncsc.mil>
+ */
+#ifndef __XEN_PCI_COMMON_H__
+#define __XEN_PCI_COMMON_H__
+
+/* Be sure to bump this number if you change this file */
+#define XEN_PCI_MAGIC "7"
+
+/* xen_pci_sharedinfo flags */
+#define _XEN_PCIF_active (0)
+#define XEN_PCIF_active (1<<_XEN_PCIF_active)
+#define _XEN_PCIB_AERHANDLER (1)
+#define XEN_PCIB_AERHANDLER (1<<_XEN_PCIB_AERHANDLER)
+#define _XEN_PCIB_active (2)
+#define XEN_PCIB_active (1<<_XEN_PCIB_active)
+
+/* xen_pci_op commands */
+#define XEN_PCI_OP_conf_read (0)
+#define XEN_PCI_OP_conf_write (1)
+#define XEN_PCI_OP_enable_msi (2)
+#define XEN_PCI_OP_disable_msi (3)
+#define XEN_PCI_OP_enable_msix (4)
+#define XEN_PCI_OP_disable_msix (5)
+#define XEN_PCI_OP_aer_detected (6)
+#define XEN_PCI_OP_aer_resume (7)
+#define XEN_PCI_OP_aer_mmio (8)
+#define XEN_PCI_OP_aer_slotreset (9)
+
+/* xen_pci_op error numbers */
+#define XEN_PCI_ERR_success (0)
+#define XEN_PCI_ERR_dev_not_found (-1)
+#define XEN_PCI_ERR_invalid_offset (-2)
+#define XEN_PCI_ERR_access_denied (-3)
+#define XEN_PCI_ERR_not_implemented (-4)
+/* XEN_PCI_ERR_op_failed - backend failed to complete the operation */
+#define XEN_PCI_ERR_op_failed (-5)
+
+/*
+ * it should be PAGE_SIZE-sizeof(struct xen_pci_op))/sizeof(struct msix_entry))
+ * Should not exceed 128
+ */
+#define SH_INFO_MAX_VEC 128
+
+struct xen_msix_entry {
+ uint16_t vector;
+ uint16_t entry;
+};
+struct xen_pci_op {
+ /* IN: what action to perform: XEN_PCI_OP_* */
+ uint32_t cmd;
+
+ /* OUT: will contain an error number (if any) from errno.h */
+ int32_t err;
+
+ /* IN: which device to touch */
+ uint32_t domain; /* PCI Domain/Segment */
+ uint32_t bus;
+ uint32_t devfn;
+
+ /* IN: which configuration registers to touch */
+ int32_t offset;
+ int32_t size;
+
+ /* IN/OUT: Contains the result after a READ or the value to WRITE */
+ uint32_t value;
+ /* IN: Contains extra infor for this operation */
+ uint32_t info;
+ /*IN: param for msi-x */
+ struct xen_msix_entry msix_entries[SH_INFO_MAX_VEC];
+};
+
+/*used for pcie aer handling*/
+struct xen_pcie_aer_op {
+ /* IN: what action to perform: XEN_PCI_OP_* */
+ uint32_t cmd;
+ /*IN/OUT: return aer_op result or carry error_detected state as input*/
+ int32_t err;
+
+ /* IN: which device to touch */
+ uint32_t domain; /* PCI Domain/Segment*/
+ uint32_t bus;
+ uint32_t devfn;
+};
+struct xen_pci_sharedinfo {
+ /* flags - XEN_PCIF_* */
+ uint32_t flags;
+ struct xen_pci_op op;
+ struct xen_pcie_aer_op aer_op;
+};
+
+#endif /* __XEN_PCI_COMMON_H__ */
diff --git a/include/xen/interface/io/protocols.h b/include/xen/interface/io/protocols.h
new file mode 100644
index 000000000..6a89dc1bf
--- /dev/null
+++ b/include/xen/interface/io/protocols.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __XEN_PROTOCOLS_H__
+#define __XEN_PROTOCOLS_H__
+
+#define XEN_IO_PROTO_ABI_X86_32 "x86_32-abi"
+#define XEN_IO_PROTO_ABI_X86_64 "x86_64-abi"
+#define XEN_IO_PROTO_ABI_POWERPC64 "powerpc64-abi"
+#define XEN_IO_PROTO_ABI_ARM "arm-abi"
+
+#if defined(__i386__)
+# define XEN_IO_PROTO_ABI_NATIVE XEN_IO_PROTO_ABI_X86_32
+#elif defined(__x86_64__)
+# define XEN_IO_PROTO_ABI_NATIVE XEN_IO_PROTO_ABI_X86_64
+#elif defined(__powerpc64__)
+# define XEN_IO_PROTO_ABI_NATIVE XEN_IO_PROTO_ABI_POWERPC64
+#elif defined(__arm__) || defined(__aarch64__)
+# define XEN_IO_PROTO_ABI_NATIVE XEN_IO_PROTO_ABI_ARM
+#else
+# error arch fixup needed here
+#endif
+
+#endif
diff --git a/include/xen/interface/io/pvcalls.h b/include/xen/interface/io/pvcalls.h
new file mode 100644
index 000000000..ccf97b817
--- /dev/null
+++ b/include/xen/interface/io/pvcalls.h
@@ -0,0 +1,121 @@
+#ifndef __XEN_PUBLIC_IO_XEN_PVCALLS_H__
+#define __XEN_PUBLIC_IO_XEN_PVCALLS_H__
+
+#include <linux/net.h>
+#include <xen/interface/io/ring.h>
+#include <xen/interface/grant_table.h>
+
+/* "1" means socket, connect, release, bind, listen, accept and poll */
+#define XENBUS_FUNCTIONS_CALLS "1"
+
+/*
+ * See docs/misc/pvcalls.markdown in xen.git for the full specification:
+ * https://xenbits.xen.org/docs/unstable/misc/pvcalls.html
+ */
+struct pvcalls_data_intf {
+ RING_IDX in_cons, in_prod, in_error;
+
+ uint8_t pad1[52];
+
+ RING_IDX out_cons, out_prod, out_error;
+
+ uint8_t pad2[52];
+
+ RING_IDX ring_order;
+ grant_ref_t ref[];
+};
+DEFINE_XEN_FLEX_RING(pvcalls);
+
+#define PVCALLS_SOCKET 0
+#define PVCALLS_CONNECT 1
+#define PVCALLS_RELEASE 2
+#define PVCALLS_BIND 3
+#define PVCALLS_LISTEN 4
+#define PVCALLS_ACCEPT 5
+#define PVCALLS_POLL 6
+
+struct xen_pvcalls_request {
+ uint32_t req_id; /* private to guest, echoed in response */
+ uint32_t cmd; /* command to execute */
+ union {
+ struct xen_pvcalls_socket {
+ uint64_t id;
+ uint32_t domain;
+ uint32_t type;
+ uint32_t protocol;
+ } socket;
+ struct xen_pvcalls_connect {
+ uint64_t id;
+ uint8_t addr[28];
+ uint32_t len;
+ uint32_t flags;
+ grant_ref_t ref;
+ uint32_t evtchn;
+ } connect;
+ struct xen_pvcalls_release {
+ uint64_t id;
+ uint8_t reuse;
+ } release;
+ struct xen_pvcalls_bind {
+ uint64_t id;
+ uint8_t addr[28];
+ uint32_t len;
+ } bind;
+ struct xen_pvcalls_listen {
+ uint64_t id;
+ uint32_t backlog;
+ } listen;
+ struct xen_pvcalls_accept {
+ uint64_t id;
+ uint64_t id_new;
+ grant_ref_t ref;
+ uint32_t evtchn;
+ } accept;
+ struct xen_pvcalls_poll {
+ uint64_t id;
+ } poll;
+ /* dummy member to force sizeof(struct xen_pvcalls_request)
+ * to match across archs */
+ struct xen_pvcalls_dummy {
+ uint8_t dummy[56];
+ } dummy;
+ } u;
+};
+
+struct xen_pvcalls_response {
+ uint32_t req_id;
+ uint32_t cmd;
+ int32_t ret;
+ uint32_t pad;
+ union {
+ struct _xen_pvcalls_socket {
+ uint64_t id;
+ } socket;
+ struct _xen_pvcalls_connect {
+ uint64_t id;
+ } connect;
+ struct _xen_pvcalls_release {
+ uint64_t id;
+ } release;
+ struct _xen_pvcalls_bind {
+ uint64_t id;
+ } bind;
+ struct _xen_pvcalls_listen {
+ uint64_t id;
+ } listen;
+ struct _xen_pvcalls_accept {
+ uint64_t id;
+ } accept;
+ struct _xen_pvcalls_poll {
+ uint64_t id;
+ } poll;
+ struct _xen_pvcalls_dummy {
+ uint8_t dummy[8];
+ } dummy;
+ } u;
+};
+
+DEFINE_RING_TYPES(xen_pvcalls, struct xen_pvcalls_request,
+ struct xen_pvcalls_response);
+
+#endif
diff --git a/include/xen/interface/io/ring.h b/include/xen/interface/io/ring.h
new file mode 100644
index 000000000..b39cdbc52
--- /dev/null
+++ b/include/xen/interface/io/ring.h
@@ -0,0 +1,455 @@
+/******************************************************************************
+ * ring.h
+ *
+ * Shared producer-consumer ring macros.
+ *
+ * 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.
+ *
+ * Tim Deegan and Andrew Warfield November 2004.
+ */
+
+#ifndef __XEN_PUBLIC_IO_RING_H__
+#define __XEN_PUBLIC_IO_RING_H__
+
+/*
+ * When #include'ing this header, you need to provide the following
+ * declaration upfront:
+ * - standard integers types (uint8_t, uint16_t, etc)
+ * They are provided by stdint.h of the standard headers.
+ *
+ * In addition, if you intend to use the FLEX macros, you also need to
+ * provide the following, before invoking the FLEX macros:
+ * - size_t
+ * - memcpy
+ * - grant_ref_t
+ * These declarations are provided by string.h of the standard headers,
+ * and grant_table.h from the Xen public headers.
+ */
+
+#include <xen/interface/grant_table.h>
+
+typedef unsigned int RING_IDX;
+
+/* Round a 32-bit unsigned constant down to the nearest power of two. */
+#define __RD2(_x) (((_x) & 0x00000002) ? 0x2 : ((_x) & 0x1))
+#define __RD4(_x) (((_x) & 0x0000000c) ? __RD2((_x)>>2)<<2 : __RD2(_x))
+#define __RD8(_x) (((_x) & 0x000000f0) ? __RD4((_x)>>4)<<4 : __RD4(_x))
+#define __RD16(_x) (((_x) & 0x0000ff00) ? __RD8((_x)>>8)<<8 : __RD8(_x))
+#define __RD32(_x) (((_x) & 0xffff0000) ? __RD16((_x)>>16)<<16 : __RD16(_x))
+
+/*
+ * Calculate size of a shared ring, given the total available space for the
+ * ring and indexes (_sz), and the name tag of the request/response structure.
+ * A ring contains as many entries as will fit, rounded down to the nearest
+ * power of two (so we can mask with (size-1) to loop around).
+ */
+#define __CONST_RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - offsetof(struct _s##_sring, ring)) / \
+ sizeof(((struct _s##_sring *)0)->ring[0])))
+/*
+ * The same for passing in an actual pointer instead of a name tag.
+ */
+#define __RING_SIZE(_s, _sz) \
+ (__RD32(((_sz) - (long)(_s)->ring + (long)(_s)) / sizeof((_s)->ring[0])))
+
+/*
+ * Macros to make the correct C datatypes for a new kind of ring.
+ *
+ * To make a new ring datatype, you need to have two message structures,
+ * let's say request_t, and response_t already defined.
+ *
+ * In a header where you want the ring datatype declared, you then do:
+ *
+ * DEFINE_RING_TYPES(mytag, request_t, response_t);
+ *
+ * These expand out to give you a set of types, as you can see below.
+ * The most important of these are:
+ *
+ * mytag_sring_t - The shared ring.
+ * mytag_front_ring_t - The 'front' half of the ring.
+ * mytag_back_ring_t - The 'back' half of the ring.
+ *
+ * To initialize a ring in your code you need to know the location and size
+ * of the shared memory area (PAGE_SIZE, for instance). To initialise
+ * the front half:
+ *
+ * mytag_front_ring_t front_ring;
+ * SHARED_RING_INIT((mytag_sring_t *)shared_page);
+ * FRONT_RING_INIT(&front_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ *
+ * Initializing the back follows similarly (note that only the front
+ * initializes the shared ring):
+ *
+ * mytag_back_ring_t back_ring;
+ * BACK_RING_INIT(&back_ring, (mytag_sring_t *)shared_page, PAGE_SIZE);
+ */
+
+#define DEFINE_RING_TYPES(__name, __req_t, __rsp_t) \
+ \
+/* Shared ring entry */ \
+union __name##_sring_entry { \
+ __req_t req; \
+ __rsp_t rsp; \
+}; \
+ \
+/* Shared ring page */ \
+struct __name##_sring { \
+ RING_IDX req_prod, req_event; \
+ RING_IDX rsp_prod, rsp_event; \
+ uint8_t __pad[48]; \
+ union __name##_sring_entry ring[1]; /* variable-length */ \
+}; \
+ \
+/* "Front" end's private variables */ \
+struct __name##_front_ring { \
+ RING_IDX req_prod_pvt; \
+ RING_IDX rsp_cons; \
+ unsigned int nr_ents; \
+ struct __name##_sring *sring; \
+}; \
+ \
+/* "Back" end's private variables */ \
+struct __name##_back_ring { \
+ RING_IDX rsp_prod_pvt; \
+ RING_IDX req_cons; \
+ unsigned int nr_ents; \
+ struct __name##_sring *sring; \
+}; \
+ \
+/*
+ * Macros for manipulating rings.
+ *
+ * FRONT_RING_whatever works on the "front end" of a ring: here
+ * requests are pushed on to the ring and responses taken off it.
+ *
+ * BACK_RING_whatever works on the "back end" of a ring: here
+ * requests are taken off the ring and responses put on.
+ *
+ * N.B. these macros do NO INTERLOCKS OR FLOW CONTROL.
+ * This is OK in 1-for-1 request-response situations where the
+ * requestor (front end) never has more than RING_SIZE()-1
+ * outstanding requests.
+ */
+
+/* Initialising empty rings */
+#define SHARED_RING_INIT(_s) do { \
+ (_s)->req_prod = (_s)->rsp_prod = 0; \
+ (_s)->req_event = (_s)->rsp_event = 1; \
+ (void)memset((_s)->__pad, 0, sizeof((_s)->__pad)); \
+} while(0)
+
+#define FRONT_RING_ATTACH(_r, _s, _i, __size) do { \
+ (_r)->req_prod_pvt = (_i); \
+ (_r)->rsp_cons = (_i); \
+ (_r)->nr_ents = __RING_SIZE(_s, __size); \
+ (_r)->sring = (_s); \
+} while (0)
+
+#define FRONT_RING_INIT(_r, _s, __size) FRONT_RING_ATTACH(_r, _s, 0, __size)
+
+#define BACK_RING_ATTACH(_r, _s, _i, __size) do { \
+ (_r)->rsp_prod_pvt = (_i); \
+ (_r)->req_cons = (_i); \
+ (_r)->nr_ents = __RING_SIZE(_s, __size); \
+ (_r)->sring = (_s); \
+} while (0)
+
+#define BACK_RING_INIT(_r, _s, __size) BACK_RING_ATTACH(_r, _s, 0, __size)
+
+/* How big is this ring? */
+#define RING_SIZE(_r) \
+ ((_r)->nr_ents)
+
+/* Number of free requests (for use on front side only). */
+#define RING_FREE_REQUESTS(_r) \
+ (RING_SIZE(_r) - ((_r)->req_prod_pvt - (_r)->rsp_cons))
+
+/* Test if there is an empty slot available on the front ring.
+ * (This is only meaningful from the front. )
+ */
+#define RING_FULL(_r) \
+ (RING_FREE_REQUESTS(_r) == 0)
+
+/* Test if there are outstanding messages to be processed on a ring. */
+#define RING_HAS_UNCONSUMED_RESPONSES(_r) \
+ ((_r)->sring->rsp_prod - (_r)->rsp_cons)
+
+#define RING_HAS_UNCONSUMED_REQUESTS(_r) ({ \
+ unsigned int req = (_r)->sring->req_prod - (_r)->req_cons; \
+ unsigned int rsp = RING_SIZE(_r) - \
+ ((_r)->req_cons - (_r)->rsp_prod_pvt); \
+ req < rsp ? req : rsp; \
+})
+
+/* Direct access to individual ring elements, by index. */
+#define RING_GET_REQUEST(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].req))
+
+#define RING_GET_RESPONSE(_r, _idx) \
+ (&((_r)->sring->ring[((_idx) & (RING_SIZE(_r) - 1))].rsp))
+
+/*
+ * Get a local copy of a request/response.
+ *
+ * Use this in preference to RING_GET_{REQUEST,RESPONSE}() so all processing is
+ * done on a local copy that cannot be modified by the other end.
+ *
+ * Note that https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 may cause this
+ * to be ineffective where dest is a struct which consists of only bitfields.
+ */
+#define RING_COPY_(type, r, idx, dest) do { \
+ /* Use volatile to force the copy into dest. */ \
+ *(dest) = *(volatile typeof(dest))RING_GET_##type(r, idx); \
+} while (0)
+
+#define RING_COPY_REQUEST(r, idx, req) RING_COPY_(REQUEST, r, idx, req)
+#define RING_COPY_RESPONSE(r, idx, rsp) RING_COPY_(RESPONSE, r, idx, rsp)
+
+/* Loop termination condition: Would the specified index overflow the ring? */
+#define RING_REQUEST_CONS_OVERFLOW(_r, _cons) \
+ (((_cons) - (_r)->rsp_prod_pvt) >= RING_SIZE(_r))
+
+/* Ill-behaved frontend determination: Can there be this many requests? */
+#define RING_REQUEST_PROD_OVERFLOW(_r, _prod) \
+ (((_prod) - (_r)->rsp_prod_pvt) > RING_SIZE(_r))
+
+/* Ill-behaved backend determination: Can there be this many responses? */
+#define RING_RESPONSE_PROD_OVERFLOW(_r, _prod) \
+ (((_prod) - (_r)->rsp_cons) > RING_SIZE(_r))
+
+#define RING_PUSH_REQUESTS(_r) do { \
+ virt_wmb(); /* back sees requests /before/ updated producer index */\
+ (_r)->sring->req_prod = (_r)->req_prod_pvt; \
+} while (0)
+
+#define RING_PUSH_RESPONSES(_r) do { \
+ virt_wmb(); /* front sees resps /before/ updated producer index */ \
+ (_r)->sring->rsp_prod = (_r)->rsp_prod_pvt; \
+} while (0)
+
+/*
+ * Notification hold-off (req_event and rsp_event):
+ *
+ * When queueing requests or responses on a shared ring, it may not always be
+ * necessary to notify the remote end. For example, if requests are in flight
+ * in a backend, the front may be able to queue further requests without
+ * notifying the back (if the back checks for new requests when it queues
+ * responses).
+ *
+ * When enqueuing requests or responses:
+ *
+ * Use RING_PUSH_{REQUESTS,RESPONSES}_AND_CHECK_NOTIFY(). The second argument
+ * is a boolean return value. True indicates that the receiver requires an
+ * asynchronous notification.
+ *
+ * After dequeuing requests or responses (before sleeping the connection):
+ *
+ * Use RING_FINAL_CHECK_FOR_REQUESTS() or RING_FINAL_CHECK_FOR_RESPONSES().
+ * The second argument is a boolean return value. True indicates that there
+ * are pending messages on the ring (i.e., the connection should not be put
+ * to sleep).
+ *
+ * These macros will set the req_event/rsp_event field to trigger a
+ * notification on the very next message that is enqueued. If you want to
+ * create batches of work (i.e., only receive a notification after several
+ * messages have been enqueued) then you will need to create a customised
+ * version of the FINAL_CHECK macro in your own code, which sets the event
+ * field appropriately.
+ */
+
+#define RING_PUSH_REQUESTS_AND_CHECK_NOTIFY(_r, _notify) do { \
+ RING_IDX __old = (_r)->sring->req_prod; \
+ RING_IDX __new = (_r)->req_prod_pvt; \
+ virt_wmb(); /* back sees requests /before/ updated producer index */\
+ (_r)->sring->req_prod = __new; \
+ virt_mb(); /* back sees new requests /before/ we check req_event */ \
+ (_notify) = ((RING_IDX)(__new - (_r)->sring->req_event) < \
+ (RING_IDX)(__new - __old)); \
+} while (0)
+
+#define RING_PUSH_RESPONSES_AND_CHECK_NOTIFY(_r, _notify) do { \
+ RING_IDX __old = (_r)->sring->rsp_prod; \
+ RING_IDX __new = (_r)->rsp_prod_pvt; \
+ virt_wmb(); /* front sees resps /before/ updated producer index */ \
+ (_r)->sring->rsp_prod = __new; \
+ virt_mb(); /* front sees new resps /before/ we check rsp_event */ \
+ (_notify) = ((RING_IDX)(__new - (_r)->sring->rsp_event) < \
+ (RING_IDX)(__new - __old)); \
+} while (0)
+
+#define RING_FINAL_CHECK_FOR_REQUESTS(_r, _work_to_do) do { \
+ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+ if (_work_to_do) break; \
+ (_r)->sring->req_event = (_r)->req_cons + 1; \
+ virt_mb(); \
+ (_work_to_do) = RING_HAS_UNCONSUMED_REQUESTS(_r); \
+} while (0)
+
+#define RING_FINAL_CHECK_FOR_RESPONSES(_r, _work_to_do) do { \
+ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+ if (_work_to_do) break; \
+ (_r)->sring->rsp_event = (_r)->rsp_cons + 1; \
+ virt_mb(); \
+ (_work_to_do) = RING_HAS_UNCONSUMED_RESPONSES(_r); \
+} while (0)
+
+
+/*
+ * DEFINE_XEN_FLEX_RING_AND_INTF defines two monodirectional rings and
+ * functions to check if there is data on the ring, and to read and
+ * write to them.
+ *
+ * DEFINE_XEN_FLEX_RING is similar to DEFINE_XEN_FLEX_RING_AND_INTF, but
+ * does not define the indexes page. As different protocols can have
+ * extensions to the basic format, this macro allow them to define their
+ * own struct.
+ *
+ * XEN_FLEX_RING_SIZE
+ * Convenience macro to calculate the size of one of the two rings
+ * from the overall order.
+ *
+ * $NAME_mask
+ * Function to apply the size mask to an index, to reduce the index
+ * within the range [0-size].
+ *
+ * $NAME_read_packet
+ * Function to read data from the ring. The amount of data to read is
+ * specified by the "size" argument.
+ *
+ * $NAME_write_packet
+ * Function to write data to the ring. The amount of data to write is
+ * specified by the "size" argument.
+ *
+ * $NAME_get_ring_ptr
+ * Convenience function that returns a pointer to read/write to the
+ * ring at the right location.
+ *
+ * $NAME_data_intf
+ * Indexes page, shared between frontend and backend. It also
+ * contains the array of grant refs.
+ *
+ * $NAME_queued
+ * Function to calculate how many bytes are currently on the ring,
+ * ready to be read. It can also be used to calculate how much free
+ * space is currently on the ring (XEN_FLEX_RING_SIZE() -
+ * $NAME_queued()).
+ */
+
+#ifndef XEN_PAGE_SHIFT
+/* The PAGE_SIZE for ring protocols and hypercall interfaces is always
+ * 4K, regardless of the architecture, and page granularity chosen by
+ * operating systems.
+ */
+#define XEN_PAGE_SHIFT 12
+#endif
+#define XEN_FLEX_RING_SIZE(order) \
+ (1UL << ((order) + XEN_PAGE_SHIFT - 1))
+
+#define DEFINE_XEN_FLEX_RING(name) \
+static inline RING_IDX name##_mask(RING_IDX idx, RING_IDX ring_size) \
+{ \
+ return idx & (ring_size - 1); \
+} \
+ \
+static inline unsigned char *name##_get_ring_ptr(unsigned char *buf, \
+ RING_IDX idx, \
+ RING_IDX ring_size) \
+{ \
+ return buf + name##_mask(idx, ring_size); \
+} \
+ \
+static inline void name##_read_packet(void *opaque, \
+ const unsigned char *buf, \
+ size_t size, \
+ RING_IDX masked_prod, \
+ RING_IDX *masked_cons, \
+ RING_IDX ring_size) \
+{ \
+ if (*masked_cons < masked_prod || \
+ size <= ring_size - *masked_cons) { \
+ memcpy(opaque, buf + *masked_cons, size); \
+ } else { \
+ memcpy(opaque, buf + *masked_cons, ring_size - *masked_cons); \
+ memcpy((unsigned char *)opaque + ring_size - *masked_cons, buf, \
+ size - (ring_size - *masked_cons)); \
+ } \
+ *masked_cons = name##_mask(*masked_cons + size, ring_size); \
+} \
+ \
+static inline void name##_write_packet(unsigned char *buf, \
+ const void *opaque, \
+ size_t size, \
+ RING_IDX *masked_prod, \
+ RING_IDX masked_cons, \
+ RING_IDX ring_size) \
+{ \
+ if (*masked_prod < masked_cons || \
+ size <= ring_size - *masked_prod) { \
+ memcpy(buf + *masked_prod, opaque, size); \
+ } else { \
+ memcpy(buf + *masked_prod, opaque, ring_size - *masked_prod); \
+ memcpy(buf, (unsigned char *)opaque + (ring_size - *masked_prod), \
+ size - (ring_size - *masked_prod)); \
+ } \
+ *masked_prod = name##_mask(*masked_prod + size, ring_size); \
+} \
+ \
+static inline RING_IDX name##_queued(RING_IDX prod, \
+ RING_IDX cons, \
+ RING_IDX ring_size) \
+{ \
+ RING_IDX size; \
+ \
+ if (prod == cons) \
+ return 0; \
+ \
+ prod = name##_mask(prod, ring_size); \
+ cons = name##_mask(cons, ring_size); \
+ \
+ if (prod == cons) \
+ return ring_size; \
+ \
+ if (prod > cons) \
+ size = prod - cons; \
+ else \
+ size = ring_size - (cons - prod); \
+ return size; \
+} \
+ \
+struct name##_data { \
+ unsigned char *in; /* half of the allocation */ \
+ unsigned char *out; /* half of the allocation */ \
+}
+
+#define DEFINE_XEN_FLEX_RING_AND_INTF(name) \
+struct name##_data_intf { \
+ RING_IDX in_cons, in_prod; \
+ \
+ uint8_t pad1[56]; \
+ \
+ RING_IDX out_cons, out_prod; \
+ \
+ uint8_t pad2[56]; \
+ \
+ RING_IDX ring_order; \
+ grant_ref_t ref[]; \
+}; \
+DEFINE_XEN_FLEX_RING(name)
+
+#endif /* __XEN_PUBLIC_IO_RING_H__ */
diff --git a/include/xen/interface/io/sndif.h b/include/xen/interface/io/sndif.h
new file mode 100644
index 000000000..2aac8f736
--- /dev/null
+++ b/include/xen/interface/io/sndif.h
@@ -0,0 +1,1081 @@
+/******************************************************************************
+ * sndif.h
+ *
+ * Unified sound-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) 2013-2015 GlobalLogic Inc.
+ * Copyright (C) 2016-2017 EPAM Systems Inc.
+ *
+ * Authors: Oleksandr Andrushchenko <oleksandr_andrushchenko@epam.com>
+ * Oleksandr Grytsov <oleksandr_grytsov@epam.com>
+ * Oleksandr Dmytryshyn <oleksandr.dmytryshyn@globallogic.com>
+ * Iurii Konovalenko <iurii.konovalenko@globallogic.com>
+ */
+
+#ifndef __XEN_PUBLIC_IO_SNDIF_H__
+#define __XEN_PUBLIC_IO_SNDIF_H__
+
+#include "ring.h"
+#include "../grant_table.h"
+
+/*
+ ******************************************************************************
+ * Protocol version
+ ******************************************************************************
+ */
+#define XENSND_PROTOCOL_VERSION 2
+
+/*
+ ******************************************************************************
+ * Feature and Parameter Negotiation
+ ******************************************************************************
+ *
+ * Front->back notifications: when enqueuing a new request, sending a
+ * notification can be made conditional on xensnd_req (i.e., the generic
+ * hold-off mechanism provided by the ring macros). Backends must set
+ * xensnd_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 xensnd_resp (i.e., the generic
+ * hold-off mechanism provided by the ring macros). Frontends must set
+ * xensnd_resp appropriately (e.g., using RING_FINAL_CHECK_FOR_RESPONSES()).
+ *
+ * The two halves of a para-virtual sound card 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 sound cards and
+ * PCM devices/streams than the underlying HW physically has by employing
+ * SW mixers, configuring virtual sound streams, channels etc.
+ *
+ * This is an example of backend and frontend configuration:
+ *
+ *--------------------------------- Backend -----------------------------------
+ *
+ * /local/domain/0/backend/vsnd/1/0/frontend-id = "1"
+ * /local/domain/0/backend/vsnd/1/0/frontend = "/local/domain/1/device/vsnd/0"
+ * /local/domain/0/backend/vsnd/1/0/state = "4"
+ * /local/domain/0/backend/vsnd/1/0/versions = "1,2"
+ *
+ *--------------------------------- Frontend ----------------------------------
+ *
+ * /local/domain/1/device/vsnd/0/backend-id = "0"
+ * /local/domain/1/device/vsnd/0/backend = "/local/domain/0/backend/vsnd/1/0"
+ * /local/domain/1/device/vsnd/0/state = "4"
+ * /local/domain/1/device/vsnd/0/version = "1"
+ *
+ *----------------------------- Card configuration ----------------------------
+ *
+ * /local/domain/1/device/vsnd/0/short-name = "Card short name"
+ * /local/domain/1/device/vsnd/0/long-name = "Card long name"
+ * /local/domain/1/device/vsnd/0/sample-rates = "8000,32000,44100,48000,96000"
+ * /local/domain/1/device/vsnd/0/sample-formats = "s8,u8,s16_le,s16_be"
+ * /local/domain/1/device/vsnd/0/buffer-size = "262144"
+ *
+ *------------------------------- PCM device 0 --------------------------------
+ *
+ * /local/domain/1/device/vsnd/0/0/name = "General analog"
+ * /local/domain/1/device/vsnd/0/0/channels-max = "5"
+ *
+ *----------------------------- Stream 0, playback ----------------------------
+ *
+ * /local/domain/1/device/vsnd/0/0/0/type = "p"
+ * /local/domain/1/device/vsnd/0/0/0/sample-formats = "s8,u8"
+ * /local/domain/1/device/vsnd/0/0/0/unique-id = "0"
+ *
+ * /local/domain/1/device/vsnd/0/0/0/ring-ref = "386"
+ * /local/domain/1/device/vsnd/0/0/0/event-channel = "15"
+ * /local/domain/1/device/vsnd/0/0/0/evt-ring-ref = "1386"
+ * /local/domain/1/device/vsnd/0/0/0/evt-event-channel = "215"
+ *
+ *------------------------------ Stream 1, capture ----------------------------
+ *
+ * /local/domain/1/device/vsnd/0/0/1/type = "c"
+ * /local/domain/1/device/vsnd/0/0/1/channels-max = "2"
+ * /local/domain/1/device/vsnd/0/0/1/unique-id = "1"
+ *
+ * /local/domain/1/device/vsnd/0/0/1/ring-ref = "384"
+ * /local/domain/1/device/vsnd/0/0/1/event-channel = "13"
+ * /local/domain/1/device/vsnd/0/0/1/evt-ring-ref = "1384"
+ * /local/domain/1/device/vsnd/0/0/1/evt-event-channel = "213"
+ *
+ *------------------------------- PCM device 1 --------------------------------
+ *
+ * /local/domain/1/device/vsnd/0/1/name = "HDMI-0"
+ * /local/domain/1/device/vsnd/0/1/sample-rates = "8000,32000,44100"
+ *
+ *------------------------------ Stream 0, capture ----------------------------
+ *
+ * /local/domain/1/device/vsnd/0/1/0/type = "c"
+ * /local/domain/1/device/vsnd/0/1/0/unique-id = "2"
+ *
+ * /local/domain/1/device/vsnd/0/1/0/ring-ref = "387"
+ * /local/domain/1/device/vsnd/0/1/0/event-channel = "151"
+ * /local/domain/1/device/vsnd/0/1/0/evt-ring-ref = "1387"
+ * /local/domain/1/device/vsnd/0/1/0/evt-event-channel = "351"
+ *
+ *------------------------------- PCM device 2 --------------------------------
+ *
+ * /local/domain/1/device/vsnd/0/2/name = "SPDIF"
+ *
+ *----------------------------- Stream 0, playback ----------------------------
+ *
+ * /local/domain/1/device/vsnd/0/2/0/type = "p"
+ * /local/domain/1/device/vsnd/0/2/0/unique-id = "3"
+ *
+ * /local/domain/1/device/vsnd/0/2/0/ring-ref = "389"
+ * /local/domain/1/device/vsnd/0/2/0/event-channel = "152"
+ * /local/domain/1/device/vsnd/0/2/0/evt-ring-ref = "1389"
+ * /local/domain/1/device/vsnd/0/2/0/evt-event-channel = "452"
+ *
+ ******************************************************************************
+ * Backend XenBus Nodes
+ ******************************************************************************
+ *
+ *----------------------------- Protocol version ------------------------------
+ *
+ * versions
+ * Values: <string>
+ *
+ * List of XENSND_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.
+ *
+ * pcm-dev-idx
+ * Values: <uint8_t>
+ *
+ * Zero based contigous index of the PCM device.
+ *
+ * stream-idx
+ * Values: <uint8_t>
+ *
+ * Zero based contigous index of the stream of the PCM device.
+ *
+ * The following pattern is used for addressing:
+ * /local/domain/<dom-id>/device/vsnd/<dev-id>/<pcm-dev-idx>/<stream-idx>/...
+ *
+ *----------------------------- Protocol version ------------------------------
+ *
+ * version
+ * Values: <string>
+ *
+ * Protocol version, chosen among the ones supported by the backend.
+ *
+ *------------------------------- PCM settings --------------------------------
+ *
+ * Every virtualized sound frontend has a set of PCM devices and streams, each
+ * could be individually configured. Part of the PCM configuration can be
+ * defined at higher level of the hierarchy and be fully or partially re-used
+ * by the underlying layers. These configuration values are:
+ * o number of channels (min/max)
+ * o supported sample rates
+ * o supported sample formats.
+ * E.g. one can define these values for the whole card, device or stream.
+ * Every underlying layer in turn can re-define some or all of them to better
+ * fit its needs. For example, card may define number of channels to be
+ * in [1; 8] range, and some particular stream may be limited to [1; 2] only.
+ * The rule is that the underlying layer must be a subset of the upper layer
+ * range.
+ *
+ * channels-min
+ * Values: <uint8_t>
+ *
+ * The minimum amount of channels that is supported, [1; channels-max].
+ * Optional, if not set or omitted a value of 1 is used.
+ *
+ * channels-max
+ * Values: <uint8_t>
+ *
+ * The maximum amount of channels that is supported.
+ * Must be at least <channels-min>.
+ *
+ * sample-rates
+ * Values: <list of uint32_t>
+ *
+ * List of supported sample rates separated by XENSND_LIST_SEPARATOR.
+ * Sample rates are expressed as a list of decimal values w/o any
+ * ordering requirement.
+ *
+ * sample-formats
+ * Values: <list of XENSND_PCM_FORMAT_XXX_STR>
+ *
+ * List of supported sample formats separated by XENSND_LIST_SEPARATOR.
+ * Items must not exceed XENSND_SAMPLE_FORMAT_MAX_LEN length.
+ *
+ * buffer-size
+ * Values: <uint32_t>
+ *
+ * The maximum size in octets of the buffer to allocate per stream.
+ *
+ *----------------------- Virtual sound card settings -------------------------
+ * short-name
+ * Values: <char[32]>
+ *
+ * Short name of the virtual sound card. Optional.
+ *
+ * long-name
+ * Values: <char[80]>
+ *
+ * Long name of the virtual sound card. Optional.
+ *
+ *----------------------------- Device settings -------------------------------
+ * name
+ * Values: <char[80]>
+ *
+ * Name of the sound device within the virtual sound card. Optional.
+ *
+ *----------------------------- Stream settings -------------------------------
+ *
+ * type
+ * Values: "p", "c"
+ *
+ * Stream type: "p" - playback stream, "c" - capture stream
+ *
+ * If both capture and playback are needed then two streams need to be
+ * defined under the same device.
+ *
+ * unique-id
+ * Values: <string>
+ *
+ * After stream initialization it is assigned a unique ID, so every
+ * stream of the frontend can be identified by the backend by this ID.
+ * This can be UUID or such.
+ *
+ *-------------------- Stream Request Transport Parameters --------------------
+ *
+ * event-channel
+ * Values: <uint32_t>
+ *
+ * The identifier of the Xen event channel used to signal activity
+ * in the ring buffer.
+ *
+ * ring-ref
+ * Values: <uint32_t>
+ *
+ * The Xen grant reference granting permission for the backend to map
+ * a sole page in a single page sized ring buffer.
+ *
+ *--------------------- Stream Event Transport Parameters ---------------------
+ *
+ * This communication path is used to deliver asynchronous events from backend
+ * to frontend, set up per stream.
+ *
+ * evt-event-channel
+ * Values: <uint32_t>
+ *
+ * The identifier of the Xen 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 in a single page sized ring buffer.
+ *
+ ******************************************************************************
+ * STATE DIAGRAMS
+ ******************************************************************************
+ *
+ * Tool stack creates front and back state nodes with initial state
+ * XenbusStateInitialising.
+ * Tool stack creates and sets up frontend sound configuration nodes per domain.
+ *
+ * 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
+ * playback/capture stream.
+ * 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 sound device instances
+ * as per configuration.
+ * |
+ * |
+ * V
+ * XenbusStateConnected
+ *
+ * XenbusStateUnknown
+ * XenbusStateClosed
+ * XenbusStateClosing
+ * o Remove virtual sound 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 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.
+ * So, 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.
+ *
+ ******************************************************************************
+ * PCM FORMATS
+ ******************************************************************************
+ *
+ * XENSND_PCM_FORMAT_<format>[_<endian>]
+ *
+ * format: <S/U/F><bits> or <name>
+ * S - signed, U - unsigned, F - float
+ * bits - 8, 16, 24, 32
+ * name - MU_LAW, GSM, etc.
+ *
+ * endian: <LE/BE>, may be absent
+ * LE - Little endian, BE - Big endian
+ */
+#define XENSND_PCM_FORMAT_S8 0
+#define XENSND_PCM_FORMAT_U8 1
+#define XENSND_PCM_FORMAT_S16_LE 2
+#define XENSND_PCM_FORMAT_S16_BE 3
+#define XENSND_PCM_FORMAT_U16_LE 4
+#define XENSND_PCM_FORMAT_U16_BE 5
+#define XENSND_PCM_FORMAT_S24_LE 6
+#define XENSND_PCM_FORMAT_S24_BE 7
+#define XENSND_PCM_FORMAT_U24_LE 8
+#define XENSND_PCM_FORMAT_U24_BE 9
+#define XENSND_PCM_FORMAT_S32_LE 10
+#define XENSND_PCM_FORMAT_S32_BE 11
+#define XENSND_PCM_FORMAT_U32_LE 12
+#define XENSND_PCM_FORMAT_U32_BE 13
+#define XENSND_PCM_FORMAT_F32_LE 14 /* 4-byte float, IEEE-754 32-bit, */
+#define XENSND_PCM_FORMAT_F32_BE 15 /* range -1.0 to 1.0 */
+#define XENSND_PCM_FORMAT_F64_LE 16 /* 8-byte float, IEEE-754 64-bit, */
+#define XENSND_PCM_FORMAT_F64_BE 17 /* range -1.0 to 1.0 */
+#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE 18
+#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE 19
+#define XENSND_PCM_FORMAT_MU_LAW 20
+#define XENSND_PCM_FORMAT_A_LAW 21
+#define XENSND_PCM_FORMAT_IMA_ADPCM 22
+#define XENSND_PCM_FORMAT_MPEG 23
+#define XENSND_PCM_FORMAT_GSM 24
+
+/*
+ ******************************************************************************
+ * REQUEST CODES
+ ******************************************************************************
+ */
+#define XENSND_OP_OPEN 0
+#define XENSND_OP_CLOSE 1
+#define XENSND_OP_READ 2
+#define XENSND_OP_WRITE 3
+#define XENSND_OP_SET_VOLUME 4
+#define XENSND_OP_GET_VOLUME 5
+#define XENSND_OP_MUTE 6
+#define XENSND_OP_UNMUTE 7
+#define XENSND_OP_TRIGGER 8
+#define XENSND_OP_HW_PARAM_QUERY 9
+
+#define XENSND_OP_TRIGGER_START 0
+#define XENSND_OP_TRIGGER_PAUSE 1
+#define XENSND_OP_TRIGGER_STOP 2
+#define XENSND_OP_TRIGGER_RESUME 3
+
+/*
+ ******************************************************************************
+ * EVENT CODES
+ ******************************************************************************
+ */
+#define XENSND_EVT_CUR_POS 0
+
+/*
+ ******************************************************************************
+ * XENSTORE FIELD AND PATH NAME STRINGS, HELPERS
+ ******************************************************************************
+ */
+#define XENSND_DRIVER_NAME "vsnd"
+
+#define XENSND_LIST_SEPARATOR ","
+/* Field names */
+#define XENSND_FIELD_BE_VERSIONS "versions"
+#define XENSND_FIELD_FE_VERSION "version"
+#define XENSND_FIELD_VCARD_SHORT_NAME "short-name"
+#define XENSND_FIELD_VCARD_LONG_NAME "long-name"
+#define XENSND_FIELD_RING_REF "ring-ref"
+#define XENSND_FIELD_EVT_CHNL "event-channel"
+#define XENSND_FIELD_EVT_RING_REF "evt-ring-ref"
+#define XENSND_FIELD_EVT_EVT_CHNL "evt-event-channel"
+#define XENSND_FIELD_DEVICE_NAME "name"
+#define XENSND_FIELD_TYPE "type"
+#define XENSND_FIELD_STREAM_UNIQUE_ID "unique-id"
+#define XENSND_FIELD_CHANNELS_MIN "channels-min"
+#define XENSND_FIELD_CHANNELS_MAX "channels-max"
+#define XENSND_FIELD_SAMPLE_RATES "sample-rates"
+#define XENSND_FIELD_SAMPLE_FORMATS "sample-formats"
+#define XENSND_FIELD_BUFFER_SIZE "buffer-size"
+
+/* Stream type field values. */
+#define XENSND_STREAM_TYPE_PLAYBACK "p"
+#define XENSND_STREAM_TYPE_CAPTURE "c"
+/* Sample rate max string length */
+#define XENSND_SAMPLE_RATE_MAX_LEN 11
+/* Sample format field values */
+#define XENSND_SAMPLE_FORMAT_MAX_LEN 24
+
+#define XENSND_PCM_FORMAT_S8_STR "s8"
+#define XENSND_PCM_FORMAT_U8_STR "u8"
+#define XENSND_PCM_FORMAT_S16_LE_STR "s16_le"
+#define XENSND_PCM_FORMAT_S16_BE_STR "s16_be"
+#define XENSND_PCM_FORMAT_U16_LE_STR "u16_le"
+#define XENSND_PCM_FORMAT_U16_BE_STR "u16_be"
+#define XENSND_PCM_FORMAT_S24_LE_STR "s24_le"
+#define XENSND_PCM_FORMAT_S24_BE_STR "s24_be"
+#define XENSND_PCM_FORMAT_U24_LE_STR "u24_le"
+#define XENSND_PCM_FORMAT_U24_BE_STR "u24_be"
+#define XENSND_PCM_FORMAT_S32_LE_STR "s32_le"
+#define XENSND_PCM_FORMAT_S32_BE_STR "s32_be"
+#define XENSND_PCM_FORMAT_U32_LE_STR "u32_le"
+#define XENSND_PCM_FORMAT_U32_BE_STR "u32_be"
+#define XENSND_PCM_FORMAT_F32_LE_STR "float_le"
+#define XENSND_PCM_FORMAT_F32_BE_STR "float_be"
+#define XENSND_PCM_FORMAT_F64_LE_STR "float64_le"
+#define XENSND_PCM_FORMAT_F64_BE_STR "float64_be"
+#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_LE_STR "iec958_subframe_le"
+#define XENSND_PCM_FORMAT_IEC958_SUBFRAME_BE_STR "iec958_subframe_be"
+#define XENSND_PCM_FORMAT_MU_LAW_STR "mu_law"
+#define XENSND_PCM_FORMAT_A_LAW_STR "a_law"
+#define XENSND_PCM_FORMAT_IMA_ADPCM_STR "ima_adpcm"
+#define XENSND_PCM_FORMAT_MPEG_STR "mpeg"
+#define XENSND_PCM_FORMAT_GSM_STR "gsm"
+
+
+/*
+ ******************************************************************************
+ * 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 sound driver communicate with
+ * each other using shared pages and event channels.
+ * Shared page contains a ring with request/response packets.
+ *
+ * Packets, used for input/output operations, e.g. read/write, set/get volume,
+ * etc., provide offset/length fields in order to allow asynchronous protocol
+ * operation with buffer space sharing: part of the buffer allocated at
+ * XENSND_OP_OPEN can be used for audio samples and part, for example,
+ * for volume control.
+ *
+ * All reserved fields in the structures below must be 0.
+ *
+ *---------------------------------- Requests ---------------------------------
+ *
+ * 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, XENSND_OP_???
+ *
+ * For all packets which use offset and length:
+ * offset - uint32_t, read or write data offset within the shared buffer,
+ * passed with XENSND_OP_OPEN request, octets,
+ * [0; XENSND_OP_OPEN.buffer_sz - 1].
+ * length - uint32_t, read or write data length, octets
+ *
+ * Request open - open a PCM stream for playback or capture:
+ *
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | XENSND_OP_OPEN | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | pcm_rate | 12
+ * +----------------+----------------+----------------+----------------+
+ * | pcm_format | pcm_channels | reserved | 16
+ * +----------------+----------------+----------------+----------------+
+ * | buffer_sz | 20
+ * +----------------+----------------+----------------+----------------+
+ * | gref_directory | 24
+ * +----------------+----------------+----------------+----------------+
+ * | period_sz | 28
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 32
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * pcm_rate - uint32_t, stream data rate, Hz
+ * pcm_format - uint8_t, XENSND_PCM_FORMAT_XXX value
+ * pcm_channels - uint8_t, number of channels of this stream,
+ * [channels-min; channels-max]
+ * buffer_sz - uint32_t, buffer size to be allocated, octets
+ * period_sz - uint32_t, event period size, octets
+ * This is the requested value of the period at which frontend would
+ * like to receive XENSND_EVT_CUR_POS notifications from the backend when
+ * stream position advances during playback/capture.
+ * It shows how many octets are expected to be played/captured before
+ * sending such an event.
+ * If set to 0 no XENSND_EVT_CUR_POS events are sent by the backend.
+ *
+ * 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)
+ */
+
+struct xensnd_open_req {
+ uint32_t pcm_rate;
+ uint8_t pcm_format;
+ uint8_t pcm_channels;
+ uint16_t reserved;
+ uint32_t buffer_sz;
+ grant_ref_t gref_directory;
+ uint32_t period_sz;
+};
+
+/*
+ * Shared page for XENSND_OP_OPEN 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 XENSND_OP_OPEN
+ *
+ * Number of grant_ref_t entries in the whole page directory is not
+ * passed, but instead can be calculated as:
+ * num_grefs_total = (XENSND_OP_OPEN.buffer_sz + XEN_PAGE_SIZE - 1) /
+ * XEN_PAGE_SIZE
+ */
+
+struct xensnd_page_directory {
+ grant_ref_t gref_dir_next_page;
+ grant_ref_t gref[1]; /* Variable length */
+};
+
+/*
+ * Request close - close an opened pcm stream:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | XENSND_OP_CLOSE| reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * Request read/write - used for read (for capture) or write (for playback):
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | offset | 12
+ * +----------------+----------------+----------------+----------------+
+ * | length | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * operation - XENSND_OP_READ for read or XENSND_OP_WRITE for write
+ */
+
+struct xensnd_rw_req {
+ uint32_t offset;
+ uint32_t length;
+};
+
+/*
+ * Request set/get volume - set/get channels' volume of the stream given:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | offset | 12
+ * +----------------+----------------+----------------+----------------+
+ * | length | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * operation - XENSND_OP_SET_VOLUME for volume set
+ * or XENSND_OP_GET_VOLUME for volume get
+ * Buffer passed with XENSND_OP_OPEN is used to exchange volume
+ * values:
+ *
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | channel[0] | 4
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | channel[i] | i*4
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | channel[N - 1] | (N-1)*4
+ * +----------------+----------------+----------------+----------------+
+ *
+ * N = XENSND_OP_OPEN.pcm_channels
+ * i - uint8_t, index of a channel
+ * channel[i] - sint32_t, volume of i-th channel
+ * Volume is expressed as a signed value in steps of 0.001 dB,
+ * while 0 being 0 dB.
+ *
+ * Request mute/unmute - mute/unmute stream:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | offset | 12
+ * +----------------+----------------+----------------+----------------+
+ * | length | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * operation - XENSND_OP_MUTE for mute or XENSND_OP_UNMUTE for unmute
+ * Buffer passed with XENSND_OP_OPEN is used to exchange mute/unmute
+ * values:
+ *
+ * 0 octet
+ * +----------------+----------------+----------------+----------------+
+ * | channel[0] | 4
+ * +----------------+----------------+----------------+----------------+
+ * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | channel[i] | i*4
+ * +----------------+----------------+----------------+----------------+
+ * +/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | channel[N - 1] | (N-1)*4
+ * +----------------+----------------+----------------+----------------+
+ *
+ * N = XENSND_OP_OPEN.pcm_channels
+ * i - uint8_t, index of a channel
+ * channel[i] - uint8_t, non-zero if i-th channel needs to be muted/unmuted
+ *
+ *------------------------------------ N.B. -----------------------------------
+ *
+ * The 'struct xensnd_rw_req' is also used for XENSND_OP_SET_VOLUME,
+ * XENSND_OP_GET_VOLUME, XENSND_OP_MUTE, XENSND_OP_UNMUTE.
+ *
+ * Request stream running state change - trigger PCM stream running state
+ * to start, stop, pause or resume:
+ *
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | _OP_TRIGGER | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | type | reserved | 12
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 16
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * type - uint8_t, XENSND_OP_TRIGGER_XXX value
+ */
+
+struct xensnd_trigger_req {
+ uint8_t type;
+};
+
+/*
+ * Request stream parameter ranges: request intervals and
+ * masks of supported ranges for stream configuration values.
+ *
+ * Sound device configuration for a particular stream is a limited subset
+ * of the multidimensional configuration available on XenStore, e.g.
+ * once the frame rate has been selected there is a limited supported range
+ * for sample rates becomes available (which might be the same set configured
+ * on XenStore or less). For example, selecting 96kHz sample rate may limit
+ * number of channels available for such configuration from 4 to 2, etc.
+ * Thus, each call to XENSND_OP_HW_PARAM_QUERY may reduce configuration
+ * space making it possible to iteratively get the final stream configuration,
+ * used in XENSND_OP_OPEN request.
+ *
+ * See response format for this request.
+ *
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | _HW_PARAM_QUERY| reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | formats mask low 32-bit | 12
+ * +----------------+----------------+----------------+----------------+
+ * | formats mask high 32-bit | 16
+ * +----------------+----------------+----------------+----------------+
+ * | min rate | 20
+ * +----------------+----------------+----------------+----------------+
+ * | max rate | 24
+ * +----------------+----------------+----------------+----------------+
+ * | min channels | 28
+ * +----------------+----------------+----------------+----------------+
+ * | max channels | 32
+ * +----------------+----------------+----------------+----------------+
+ * | min buffer frames | 36
+ * +----------------+----------------+----------------+----------------+
+ * | max buffer frames | 40
+ * +----------------+----------------+----------------+----------------+
+ * | min period frames | 44
+ * +----------------+----------------+----------------+----------------+
+ * | max period frames | 48
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 52
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * formats - uint64_t, bit mask representing values of the parameter
+ * made as bitwise OR of (1 << XENSND_PCM_FORMAT_XXX) values
+ *
+ * For interval parameters:
+ * min - uint32_t, minimum value of the parameter
+ * max - uint32_t, maximum value of the parameter
+ *
+ * Frame is defined as a product of the number of channels by the
+ * number of octets per one sample.
+ */
+
+struct xensnd_query_hw_param {
+ uint64_t formats;
+ struct {
+ uint32_t min;
+ uint32_t max;
+ } rates;
+ struct {
+ uint32_t min;
+ uint32_t max;
+ } channels;
+ struct {
+ uint32_t min;
+ uint32_t max;
+ } buffer;
+ struct {
+ uint32_t min;
+ uint32_t max;
+ } period;
+};
+
+/*
+ *---------------------------------- Responses --------------------------------
+ *
+ * All response packets have the same length (64 octets)
+ *
+ * All response packets have common header:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | status | 8
+ * +----------------+----------------+----------------+----------------+
+ *
+ * id - uint16_t, copied from the request
+ * operation - uint8_t, XENSND_OP_* - copied from request
+ * status - int32_t, response status, zero on success and -XEN_EXX on failure
+ *
+ *
+ * HW parameter query response - response for XENSND_OP_HW_PARAM_QUERY:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | operation | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | status | 8
+ * +----------------+----------------+----------------+----------------+
+ * | formats mask low 32-bit | 12
+ * +----------------+----------------+----------------+----------------+
+ * | formats mask high 32-bit | 16
+ * +----------------+----------------+----------------+----------------+
+ * | min rate | 20
+ * +----------------+----------------+----------------+----------------+
+ * | max rate | 24
+ * +----------------+----------------+----------------+----------------+
+ * | min channels | 28
+ * +----------------+----------------+----------------+----------------+
+ * | max channels | 32
+ * +----------------+----------------+----------------+----------------+
+ * | min buffer frames | 36
+ * +----------------+----------------+----------------+----------------+
+ * | max buffer frames | 40
+ * +----------------+----------------+----------------+----------------+
+ * | min period frames | 44
+ * +----------------+----------------+----------------+----------------+
+ * | max period frames | 48
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 52
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * Meaning of the values in this response is the same as for
+ * XENSND_OP_HW_PARAM_QUERY request.
+ */
+
+/*
+ *----------------------------------- Events ----------------------------------
+ *
+ * Events are sent via 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
+ *
+ *
+ * Current stream position - event from back to front when stream's
+ * playback/capture position has advanced:
+ * 0 1 2 3 octet
+ * +----------------+----------------+----------------+----------------+
+ * | id | _EVT_CUR_POS | reserved | 4
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 8
+ * +----------------+----------------+----------------+----------------+
+ * | position low 32-bit | 12
+ * +----------------+----------------+----------------+----------------+
+ * | position high 32-bit | 16
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 20
+ * +----------------+----------------+----------------+----------------+
+ * |/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/|
+ * +----------------+----------------+----------------+----------------+
+ * | reserved | 64
+ * +----------------+----------------+----------------+----------------+
+ *
+ * position - current value of stream's playback/capture position, octets
+ *
+ */
+
+struct xensnd_cur_pos_evt {
+ uint64_t position;
+};
+
+struct xensnd_req {
+ uint16_t id;
+ uint8_t operation;
+ uint8_t reserved[5];
+ union {
+ struct xensnd_open_req open;
+ struct xensnd_rw_req rw;
+ struct xensnd_trigger_req trigger;
+ struct xensnd_query_hw_param hw_param;
+ uint8_t reserved[56];
+ } op;
+};
+
+struct xensnd_resp {
+ uint16_t id;
+ uint8_t operation;
+ uint8_t reserved;
+ int32_t status;
+ union {
+ struct xensnd_query_hw_param hw_param;
+ uint8_t reserved1[56];
+ } resp;
+};
+
+struct xensnd_evt {
+ uint16_t id;
+ uint8_t type;
+ uint8_t reserved[5];
+ union {
+ struct xensnd_cur_pos_evt cur_pos;
+ uint8_t reserved[56];
+ } op;
+};
+
+DEFINE_RING_TYPES(xen_sndif, struct xensnd_req, struct xensnd_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 xensnd_event_page {
+ uint32_t in_cons;
+ uint32_t in_prod;
+ uint8_t reserved[56];
+};
+
+#define XENSND_EVENT_PAGE_SIZE XEN_PAGE_SIZE
+#define XENSND_IN_RING_OFFS (sizeof(struct xensnd_event_page))
+#define XENSND_IN_RING_SIZE (XENSND_EVENT_PAGE_SIZE - XENSND_IN_RING_OFFS)
+#define XENSND_IN_RING_LEN (XENSND_IN_RING_SIZE / sizeof(struct xensnd_evt))
+#define XENSND_IN_RING(page) \
+ ((struct xensnd_evt *)((char *)(page) + XENSND_IN_RING_OFFS))
+#define XENSND_IN_RING_REF(page, idx) \
+ (XENSND_IN_RING((page))[(idx) % XENSND_IN_RING_LEN])
+
+#endif /* __XEN_PUBLIC_IO_SNDIF_H__ */
diff --git a/include/xen/interface/io/tpmif.h b/include/xen/interface/io/tpmif.h
new file mode 100644
index 000000000..f8aa8bac5
--- /dev/null
+++ b/include/xen/interface/io/tpmif.h
@@ -0,0 +1,52 @@
+/******************************************************************************
+ * tpmif.h
+ *
+ * TPM I/O interface for Xen guest OSes, v2
+ *
+ * This file is in the public domain.
+ *
+ */
+
+#ifndef __XEN_PUBLIC_IO_TPMIF_H__
+#define __XEN_PUBLIC_IO_TPMIF_H__
+
+/*
+ * Xenbus state machine
+ *
+ * Device open:
+ * 1. Both ends start in XenbusStateInitialising
+ * 2. Backend transitions to InitWait (frontend does not wait on this step)
+ * 3. Frontend populates ring-ref, event-channel, feature-protocol-v2
+ * 4. Frontend transitions to Initialised
+ * 5. Backend maps grant and event channel, verifies feature-protocol-v2
+ * 6. Backend transitions to Connected
+ * 7. Frontend verifies feature-protocol-v2, transitions to Connected
+ *
+ * Device close:
+ * 1. State is changed to XenbusStateClosing
+ * 2. Frontend transitions to Closed
+ * 3. Backend unmaps grant and event, changes state to InitWait
+ */
+
+enum vtpm_shared_page_state {
+ VTPM_STATE_IDLE, /* no contents / vTPM idle / cancel complete */
+ VTPM_STATE_SUBMIT, /* request ready / vTPM working */
+ VTPM_STATE_FINISH, /* response ready / vTPM idle */
+ VTPM_STATE_CANCEL, /* cancel requested / vTPM working */
+};
+/* The backend should only change state to IDLE or FINISH, while the
+ * frontend should only change to SUBMIT or CANCEL. */
+
+
+struct vtpm_shared_page {
+ uint32_t length; /* request/response length in bytes */
+
+ uint8_t state; /* enum vtpm_shared_page_state */
+ uint8_t locality; /* for the current request */
+ uint8_t pad;
+
+ uint8_t nr_extra_pages; /* extra pages for long packets; may be zero */
+ uint32_t extra_pages[]; /* grant IDs; length in nr_extra_pages */
+};
+
+#endif
diff --git a/include/xen/interface/io/vscsiif.h b/include/xen/interface/io/vscsiif.h
new file mode 100644
index 000000000..d07d7aca8
--- /dev/null
+++ b/include/xen/interface/io/vscsiif.h
@@ -0,0 +1,229 @@
+/******************************************************************************
+ * vscsiif.h
+ *
+ * Based on the blkif.h code.
+ *
+ * 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) FUJITSU Limited 2008.
+ */
+
+#ifndef __XEN__PUBLIC_IO_SCSI_H__
+#define __XEN__PUBLIC_IO_SCSI_H__
+
+#include "ring.h"
+#include "../grant_table.h"
+
+/*
+ * Feature and Parameter Negotiation
+ * =================================
+ * The two halves of a Xen pvSCSI driver utilize nodes within the XenStore to
+ * communicate capabilities and to negotiate operating parameters. This
+ * section enumerates these nodes which reside in the respective front and
+ * backend portions of the XenStore, following the XenBus convention.
+ *
+ * Any specified default value is in effect if the corresponding XenBus node
+ * is not present in the XenStore.
+ *
+ * XenStore nodes in sections marked "PRIVATE" are solely for use by the
+ * driver side whose XenBus tree contains them.
+ *
+ *****************************************************************************
+ * Backend XenBus Nodes
+ *****************************************************************************
+ *
+ *------------------ Backend Device Identification (PRIVATE) ------------------
+ *
+ * p-devname
+ * Values: string
+ *
+ * A free string used to identify the physical device (e.g. a disk name).
+ *
+ * p-dev
+ * Values: string
+ *
+ * A string specifying the backend device: either a 4-tuple "h:c:t:l"
+ * (host, controller, target, lun, all integers), or a WWN (e.g.
+ * "naa.60014054ac780582").
+ *
+ * v-dev
+ * Values: string
+ *
+ * A string specifying the frontend device in form of a 4-tuple "h:c:t:l"
+ * (host, controller, target, lun, all integers).
+ *
+ *--------------------------------- Features ---------------------------------
+ *
+ * feature-sg-grant
+ * Values: unsigned [VSCSIIF_SG_TABLESIZE...65535]
+ * Default Value: 0
+ *
+ * Specifies the maximum number of scatter/gather elements in grant pages
+ * supported. If not set, the backend supports up to VSCSIIF_SG_TABLESIZE
+ * SG elements specified directly in the request.
+ *
+ *****************************************************************************
+ * Frontend XenBus Nodes
+ *****************************************************************************
+ *
+ *----------------------- Request Transport Parameters -----------------------
+ *
+ * event-channel
+ * Values: unsigned
+ *
+ * The identifier of the Xen event channel used to signal activity
+ * in the ring buffer.
+ *
+ * ring-ref
+ * Values: unsigned
+ *
+ * The Xen grant reference granting permission for the backend to map
+ * the sole page in a single page sized ring buffer.
+ *
+ * protocol
+ * Values: string (XEN_IO_PROTO_ABI_*)
+ * Default Value: XEN_IO_PROTO_ABI_NATIVE
+ *
+ * The machine ABI rules governing the format of all ring request and
+ * response structures.
+ */
+
+/* Requests from the frontend to the backend */
+
+/*
+ * Request a SCSI operation specified via a CDB in vscsiif_request.cmnd.
+ * The target is specified via channel, id and lun.
+ *
+ * The operation to be performed is specified via a CDB in cmnd[], the length
+ * of the CDB is in cmd_len. sc_data_direction specifies the direction of data
+ * (to the device, from the device, or none at all).
+ *
+ * If data is to be transferred to or from the device the buffer(s) in the
+ * guest memory is/are specified via one or multiple scsiif_request_segment
+ * descriptors each specifying a memory page via a grant_ref_t, a offset into
+ * the page and the length of the area in that page. All scsiif_request_segment
+ * areas concatenated form the resulting data buffer used by the operation.
+ * If the number of scsiif_request_segment areas is not too large (less than
+ * or equal VSCSIIF_SG_TABLESIZE) the areas can be specified directly in the
+ * seg[] array and the number of valid scsiif_request_segment elements is to be
+ * set in nr_segments.
+ *
+ * If "feature-sg-grant" in the Xenstore is set it is possible to specify more
+ * than VSCSIIF_SG_TABLESIZE scsiif_request_segment elements via indirection.
+ * The maximum number of allowed scsiif_request_segment elements is the value
+ * of the "feature-sg-grant" entry from Xenstore. When using indirection the
+ * seg[] array doesn't contain specifications of the data buffers, but
+ * references to scsiif_request_segment arrays, which in turn reference the
+ * data buffers. While nr_segments holds the number of populated seg[] entries
+ * (plus the set VSCSIIF_SG_GRANT bit), the number of scsiif_request_segment
+ * elements referencing the target data buffers is calculated from the lengths
+ * of the seg[] elements (the sum of all valid seg[].length divided by the
+ * size of one scsiif_request_segment structure).
+ */
+#define VSCSIIF_ACT_SCSI_CDB 1
+
+/*
+ * Request abort of a running operation for the specified target given by
+ * channel, id, lun and the operation's rqid in ref_rqid.
+ */
+#define VSCSIIF_ACT_SCSI_ABORT 2
+
+/*
+ * Request a device reset of the specified target (channel and id).
+ */
+#define VSCSIIF_ACT_SCSI_RESET 3
+
+/*
+ * Preset scatter/gather elements for a following request. Deprecated.
+ * Keeping the define only to avoid usage of the value "4" for other actions.
+ */
+#define VSCSIIF_ACT_SCSI_SG_PRESET 4
+
+/*
+ * Maximum scatter/gather segments per request.
+ *
+ * Considering balance between allocating at least 16 "vscsiif_request"
+ * structures on one page (4096 bytes) and the number of scatter/gather
+ * elements needed, we decided to use 26 as a magic number.
+ *
+ * If "feature-sg-grant" is set, more scatter/gather elements can be specified
+ * by placing them in one or more (up to VSCSIIF_SG_TABLESIZE) granted pages.
+ * In this case the vscsiif_request seg elements don't contain references to
+ * the user data, but to the SG elements referencing the user data.
+ */
+#define VSCSIIF_SG_TABLESIZE 26
+
+/*
+ * based on Linux kernel 2.6.18, still valid
+ * Changing these values requires support of multiple protocols via the rings
+ * as "old clients" will blindly use these values and the resulting structure
+ * sizes.
+ */
+#define VSCSIIF_MAX_COMMAND_SIZE 16
+#define VSCSIIF_SENSE_BUFFERSIZE 96
+
+struct scsiif_request_segment {
+ grant_ref_t gref;
+ uint16_t offset;
+ uint16_t length;
+};
+
+#define VSCSIIF_SG_PER_PAGE (PAGE_SIZE / sizeof(struct scsiif_request_segment))
+
+/* Size of one request is 252 bytes */
+struct vscsiif_request {
+ uint16_t rqid; /* private guest value, echoed in resp */
+ uint8_t act; /* command between backend and frontend */
+ uint8_t cmd_len; /* valid CDB bytes */
+
+ uint8_t cmnd[VSCSIIF_MAX_COMMAND_SIZE]; /* the CDB */
+ uint16_t timeout_per_command; /* deprecated */
+ uint16_t channel, id, lun; /* (virtual) device specification */
+ uint16_t ref_rqid; /* command abort reference */
+ uint8_t sc_data_direction; /* for DMA_TO_DEVICE(1)
+ DMA_FROM_DEVICE(2)
+ DMA_NONE(3) requests */
+ uint8_t nr_segments; /* Number of pieces of scatter-gather */
+/*
+ * flag in nr_segments: SG elements via grant page
+ *
+ * If VSCSIIF_SG_GRANT is set, the low 7 bits of nr_segments specify the number
+ * of grant pages containing SG elements. Usable if "feature-sg-grant" set.
+ */
+#define VSCSIIF_SG_GRANT 0x80
+
+ struct scsiif_request_segment seg[VSCSIIF_SG_TABLESIZE];
+ uint32_t reserved[3];
+};
+
+/* Size of one response is 252 bytes */
+struct vscsiif_response {
+ uint16_t rqid; /* identifies request */
+ uint8_t padding;
+ uint8_t sense_len;
+ uint8_t sense_buffer[VSCSIIF_SENSE_BUFFERSIZE];
+ int32_t rslt;
+ uint32_t residual_len; /* request bufflen -
+ return the value from physical device */
+ uint32_t reserved[36];
+};
+
+DEFINE_RING_TYPES(vscsiif, struct vscsiif_request, struct vscsiif_response);
+
+#endif /*__XEN__PUBLIC_IO_SCSI_H__*/
diff --git a/include/xen/interface/io/xenbus.h b/include/xen/interface/io/xenbus.h
new file mode 100644
index 000000000..aaf2951b1
--- /dev/null
+++ b/include/xen/interface/io/xenbus.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*****************************************************************************
+ * xenbus.h
+ *
+ * Xenbus protocol details.
+ *
+ * Copyright (C) 2005 XenSource Ltd.
+ */
+
+#ifndef _XEN_PUBLIC_IO_XENBUS_H
+#define _XEN_PUBLIC_IO_XENBUS_H
+
+/* The state of either end of the Xenbus, i.e. the current communication
+ status of initialisation across the bus. States here imply nothing about
+ the state of the connection between the driver and the kernel's device
+ layers. */
+enum xenbus_state
+{
+ XenbusStateUnknown = 0,
+ XenbusStateInitialising = 1,
+ XenbusStateInitWait = 2, /* Finished early
+ initialisation, but waiting
+ for information from the peer
+ or hotplug scripts. */
+ XenbusStateInitialised = 3, /* Initialised and waiting for a
+ connection from the peer. */
+ XenbusStateConnected = 4,
+ XenbusStateClosing = 5, /* The device is being closed
+ due to an error or an unplug
+ event. */
+ XenbusStateClosed = 6,
+
+ /*
+ * Reconfiguring: The device is being reconfigured.
+ */
+ XenbusStateReconfiguring = 7,
+
+ XenbusStateReconfigured = 8
+};
+
+#endif /* _XEN_PUBLIC_IO_XENBUS_H */
+
+/*
+ * Local variables:
+ * c-file-style: "linux"
+ * indent-tabs-mode: t
+ * c-indent-level: 8
+ * c-basic-offset: 8
+ * tab-width: 8
+ * End:
+ */
diff --git a/include/xen/interface/io/xs_wire.h b/include/xen/interface/io/xs_wire.h
new file mode 100644
index 000000000..1517c7e93
--- /dev/null
+++ b/include/xen/interface/io/xs_wire.h
@@ -0,0 +1,95 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Details of the "wire" protocol between Xen Store Daemon and client
+ * library or guest kernel.
+ * Copyright (C) 2005 Rusty Russell IBM Corporation
+ */
+
+#ifndef _XS_WIRE_H
+#define _XS_WIRE_H
+
+enum xsd_sockmsg_type
+{
+ XS_DEBUG,
+ XS_DIRECTORY,
+ XS_READ,
+ XS_GET_PERMS,
+ XS_WATCH,
+ XS_UNWATCH,
+ XS_TRANSACTION_START,
+ XS_TRANSACTION_END,
+ XS_INTRODUCE,
+ XS_RELEASE,
+ XS_GET_DOMAIN_PATH,
+ XS_WRITE,
+ XS_MKDIR,
+ XS_RM,
+ XS_SET_PERMS,
+ XS_WATCH_EVENT,
+ XS_ERROR,
+ XS_IS_DOMAIN_INTRODUCED,
+ XS_RESUME,
+ XS_SET_TARGET,
+ XS_RESTRICT,
+ XS_RESET_WATCHES,
+};
+
+#define XS_WRITE_NONE "NONE"
+#define XS_WRITE_CREATE "CREATE"
+#define XS_WRITE_CREATE_EXCL "CREATE|EXCL"
+
+/* We hand errors as strings, for portability. */
+struct xsd_errors
+{
+ int errnum;
+ const char *errstring;
+};
+#define XSD_ERROR(x) { x, #x }
+static struct xsd_errors xsd_errors[] __attribute__((unused)) = {
+ XSD_ERROR(EINVAL),
+ XSD_ERROR(EACCES),
+ XSD_ERROR(EEXIST),
+ XSD_ERROR(EISDIR),
+ XSD_ERROR(ENOENT),
+ XSD_ERROR(ENOMEM),
+ XSD_ERROR(ENOSPC),
+ XSD_ERROR(EIO),
+ XSD_ERROR(ENOTEMPTY),
+ XSD_ERROR(ENOSYS),
+ XSD_ERROR(EROFS),
+ XSD_ERROR(EBUSY),
+ XSD_ERROR(EAGAIN),
+ XSD_ERROR(EISCONN)
+};
+
+struct xsd_sockmsg
+{
+ uint32_t type; /* XS_??? */
+ uint32_t req_id;/* Request identifier, echoed in daemon's response. */
+ uint32_t tx_id; /* Transaction id (0 if not related to a transaction). */
+ uint32_t len; /* Length of data following this. */
+
+ /* Generally followed by nul-terminated string(s). */
+};
+
+enum xs_watch_type
+{
+ XS_WATCH_PATH = 0,
+ XS_WATCH_TOKEN
+};
+
+/* Inter-domain shared memory communications. */
+#define XENSTORE_RING_SIZE 1024
+typedef uint32_t XENSTORE_RING_IDX;
+#define MASK_XENSTORE_IDX(idx) ((idx) & (XENSTORE_RING_SIZE-1))
+struct xenstore_domain_interface {
+ char req[XENSTORE_RING_SIZE]; /* Requests to xenstore daemon. */
+ char rsp[XENSTORE_RING_SIZE]; /* Replies and async watch events. */
+ XENSTORE_RING_IDX req_cons, req_prod;
+ XENSTORE_RING_IDX rsp_cons, rsp_prod;
+};
+
+/* Violating this is very bad. See docs/misc/xenstore.txt. */
+#define XENSTORE_PAYLOAD_MAX 4096
+
+#endif /* _XS_WIRE_H */