Introduce Virtio-loopback epsilon release:

Epsilon release introduces a new compatibility layer which make virtio-loopback
design to work with QEMU and rust-vmm vhost-user backend without require any
changes.

Signed-off-by: Timos Ampelikiotis <t.ampelikiotis@virtualopensystems.com>
Change-Id: I52e57563e08a7d0bdc002f8e928ee61ba0c53dd9

1 files changed, 399 insertions, 0 deletions

diff --git a/qapi/block-export.json b/qapi/block-export.json
new file mode 100644
index 000000000..c1b92ce1c
--- /dev/null
+++ b/qapi/block-export.json
@@ -0,0 +1,399 @@
+# -*- Mode: Python -*-
+# vim: filetype=python
+
+##
+# == Block device exports
+##
+
+{ 'include': 'sockets.json' }
+
+##
+# @NbdServerOptions:
+#
+# Keep this type consistent with the nbd-server-start arguments. The only
+# intended difference is using SocketAddress instead of SocketAddressLegacy.
+#
+# @addr: Address on which to listen.
+# @tls-creds: ID of the TLS credentials object (since 2.6).
+# @tls-authz: ID of the QAuthZ authorization object used to validate
+#             the client's x509 distinguished name. This object is
+#             is only resolved at time of use, so can be deleted and
+#             recreated on the fly while the NBD server is active.
+#             If missing, it will default to denying access (since 4.0).
+# @max-connections: The maximum number of connections to allow at the same
+#                   time, 0 for unlimited. (since 5.2; default: 0)
+#
+# Since: 4.2
+##
+{ 'struct': 'NbdServerOptions',
+  'data': { 'addr': 'SocketAddress',
+            '*tls-creds': 'str',
+            '*tls-authz': 'str',
+            '*max-connections': 'uint32' } }
+
+##
+# @nbd-server-start:
+#
+# Start an NBD server listening on the given host and port.  Block
+# devices can then be exported using @nbd-server-add.  The NBD
+# server will present them as named exports; for example, another
+# QEMU instance could refer to them as "nbd:HOST:PORT:exportname=NAME".
+#
+# Keep this type consistent with the NbdServerOptions type. The only intended
+# difference is using SocketAddressLegacy instead of SocketAddress.
+#
+# @addr: Address on which to listen.
+# @tls-creds: ID of the TLS credentials object (since 2.6).
+# @tls-authz: ID of the QAuthZ authorization object used to validate
+#             the client's x509 distinguished name. This object is
+#             is only resolved at time of use, so can be deleted and
+#             recreated on the fly while the NBD server is active.
+#             If missing, it will default to denying access (since 4.0).
+# @max-connections: The maximum number of connections to allow at the same
+#                   time, 0 for unlimited. (since 5.2; default: 0)
+#
+# Returns: error if the server is already running.
+#
+# Since: 1.3
+##
+{ 'command': 'nbd-server-start',
+  'data': { 'addr': 'SocketAddressLegacy',
+            '*tls-creds': 'str',
+            '*tls-authz': 'str',
+            '*max-connections': 'uint32' } }
+
+##
+# @BlockExportOptionsNbdBase:
+#
+# An NBD block export (common options shared between nbd-server-add and
+# the NBD branch of block-export-add).
+#
+# @name: Export name. If unspecified, the @device parameter is used as the
+#        export name. (Since 2.12)
+#
+# @description: Free-form description of the export, up to 4096 bytes.
+#               (Since 5.0)
+#
+# Since: 5.0
+##
+{ 'struct': 'BlockExportOptionsNbdBase',
+  'data': { '*name': 'str', '*description': 'str' } }
+
+##
+# @BlockExportOptionsNbd:
+#
+# An NBD block export (distinct options used in the NBD branch of
+# block-export-add).
+#
+# @bitmaps: Also export each of the named dirty bitmaps reachable from
+#           @device, so the NBD client can use NBD_OPT_SET_META_CONTEXT with
+#           the metadata context name "qemu:dirty-bitmap:BITMAP" to inspect
+#           each bitmap.
+#
+# @allocation-depth: Also export the allocation depth map for @device, so
+#                    the NBD client can use NBD_OPT_SET_META_CONTEXT with
+#                    the metadata context name "qemu:allocation-depth" to
+#                    inspect allocation details. (since 5.2)
+#
+# Since: 5.2
+##
+{ 'struct': 'BlockExportOptionsNbd',
+  'base': 'BlockExportOptionsNbdBase',
+  'data': { '*bitmaps': ['str'], '*allocation-depth': 'bool' } }
+
+##
+# @BlockExportOptionsVhostUserBlk:
+#
+# A vhost-user-blk block export.
+#
+# @addr: The vhost-user socket on which to listen. Both 'unix' and 'fd'
+#        SocketAddress types are supported. Passed fds must be UNIX domain
+#        sockets.
+# @logical-block-size: Logical block size in bytes. Defaults to 512 bytes.
+# @num-queues: Number of request virtqueues. Must be greater than 0. Defaults
+#              to 1.
+#
+# Since: 5.2
+##
+{ 'struct': 'BlockExportOptionsVhostUserBlk',
+  'data': { 'addr': 'SocketAddress',
+	    '*logical-block-size': 'size',
+            '*num-queues': 'uint16'} }
+
+##
+# @FuseExportAllowOther:
+#
+# Possible allow_other modes for FUSE exports.
+#
+# @off: Do not pass allow_other as a mount option.
+#
+# @on: Pass allow_other as a mount option.
+#
+# @auto: Try mounting with allow_other first, and if that fails, retry
+#        without allow_other.
+#
+# Since: 6.1
+##
+{ 'enum': 'FuseExportAllowOther',
+  'data': ['off', 'on', 'auto'] }
+
+##
+# @BlockExportOptionsFuse:
+#
+# Options for exporting a block graph node on some (file) mountpoint
+# as a raw image.
+#
+# @mountpoint: Path on which to export the block device via FUSE.
+#              This must point to an existing regular file.
+#
+# @growable: Whether writes beyond the EOF should grow the block node
+#            accordingly. (default: false)
+#
+# @allow-other: If this is off, only qemu's user is allowed access to
+#               this export.  That cannot be changed even with chmod or
+#               chown.
+#               Enabling this option will allow other users access to
+#               the export with the FUSE mount option "allow_other".
+#               Note that using allow_other as a non-root user requires
+#               user_allow_other to be enabled in the global fuse.conf
+#               configuration file.
+#               In auto mode (the default), the FUSE export driver will
+#               first attempt to mount the export with allow_other, and
+#               if that fails, try again without.
+#               (since 6.1; default: auto)
+#
+# Since: 6.0
+##
+{ 'struct': 'BlockExportOptionsFuse',
+  'data': { 'mountpoint': 'str',
+            '*growable': 'bool',
+            '*allow-other': 'FuseExportAllowOther' },
+  'if': 'CONFIG_FUSE' }
+
+##
+# @NbdServerAddOptions:
+#
+# An NBD block export, per legacy nbd-server-add command.
+#
+# @device: The device name or node name of the node to be exported
+#
+# @writable: Whether clients should be able to write to the device via the
+#            NBD connection (default false).
+#
+# @bitmap: Also export a single dirty bitmap reachable from @device, so the
+#          NBD client can use NBD_OPT_SET_META_CONTEXT with the metadata
+#          context name "qemu:dirty-bitmap:BITMAP" to inspect the bitmap
+#          (since 4.0).
+#
+# Since: 5.0
+##
+{ 'struct': 'NbdServerAddOptions',
+  'base': 'BlockExportOptionsNbdBase',
+  'data': { 'device': 'str',
+            '*writable': 'bool', '*bitmap': 'str' } }
+
+##
+# @nbd-server-add:
+#
+# Export a block node to QEMU's embedded NBD server.
+#
+# The export name will be used as the id for the resulting block export.
+#
+# Features:
+# @deprecated: This command is deprecated. Use @block-export-add instead.
+#
+# Returns: error if the server is not running, or export with the same name
+#          already exists.
+#
+# Since: 1.3
+##
+{ 'command': 'nbd-server-add',
+  'data': 'NbdServerAddOptions', 'boxed': true, 'features': ['deprecated'] }
+
+##
+# @BlockExportRemoveMode:
+#
+# Mode for removing a block export.
+#
+# @safe: Remove export if there are no existing connections, fail otherwise.
+#
+# @hard: Drop all connections immediately and remove export.
+#
+# Potential additional modes to be added in the future:
+#
+# hide: Just hide export from new clients, leave existing connections as is.
+# Remove export after all clients are disconnected.
+#
+# soft: Hide export from new clients, answer with ESHUTDOWN for all further
+# requests from existing clients.
+#
+# Since: 2.12
+##
+{'enum': 'BlockExportRemoveMode', 'data': ['safe', 'hard']}
+
+##
+# @nbd-server-remove:
+#
+# Remove NBD export by name.
+#
+# @name: Block export id.
+#
+# @mode: Mode of command operation. See @BlockExportRemoveMode description.
+#        Default is 'safe'.
+#
+# Features:
+# @deprecated: This command is deprecated. Use @block-export-del instead.
+#
+# Returns: error if
+#            - the server is not running
+#            - export is not found
+#            - mode is 'safe' and there are existing connections
+#
+# Since: 2.12
+##
+{ 'command': 'nbd-server-remove',
+  'data': {'name': 'str', '*mode': 'BlockExportRemoveMode'},
+  'features': ['deprecated'] }
+
+##
+# @nbd-server-stop:
+#
+# Stop QEMU's embedded NBD server, and unregister all devices previously
+# added via @nbd-server-add.
+#
+# Since: 1.3
+##
+{ 'command': 'nbd-server-stop' }
+
+##
+# @BlockExportType:
+#
+# An enumeration of block export types
+#
+# @nbd: NBD export
+# @vhost-user-blk: vhost-user-blk export (since 5.2)
+# @fuse: FUSE export (since: 6.0)
+#
+# Since: 4.2
+##
+{ 'enum': 'BlockExportType',
+  'data': [ 'nbd', 'vhost-user-blk',
+            { 'name': 'fuse', 'if': 'CONFIG_FUSE' } ] }
+
+##
+# @BlockExportOptions:
+#
+# Describes a block export, i.e. how single node should be exported on an
+# external interface.
+#
+# @id: A unique identifier for the block export (across all export types)
+#
+# @node-name: The node name of the block node to be exported (since: 5.2)
+#
+# @writable: True if clients should be able to write to the export
+#            (default false)
+#
+# @writethrough: If true, caches are flushed after every write request to the
+#                export before completion is signalled. (since: 5.2;
+#                default: false)
+#
+# @iothread: The name of the iothread object where the export will run. The
+#            default is to use the thread currently associated with the
+#            block node. (since: 5.2)
+#
+# @fixed-iothread: True prevents the block node from being moved to another
+#                  thread while the export is active. If true and @iothread is
+#                  given, export creation fails if the block node cannot be
+#                  moved to the iothread. The default is false. (since: 5.2)
+#
+# Since: 4.2
+##
+{ 'union': 'BlockExportOptions',
+  'base': { 'type': 'BlockExportType',
+            'id': 'str',
+            '*fixed-iothread': 'bool',
+            '*iothread': 'str',
+            'node-name': 'str',
+            '*writable': 'bool',
+            '*writethrough': 'bool' },
+  'discriminator': 'type',
+  'data': {
+      'nbd': 'BlockExportOptionsNbd',
+      'vhost-user-blk': 'BlockExportOptionsVhostUserBlk',
+      'fuse': { 'type': 'BlockExportOptionsFuse',
+                'if': 'CONFIG_FUSE' }
+   } }
+
+##
+# @block-export-add:
+#
+# Creates a new block export.
+#
+# Since: 5.2
+##
+{ 'command': 'block-export-add',
+  'data': 'BlockExportOptions', 'boxed': true }
+
+##
+# @block-export-del:
+#
+# Request to remove a block export. This drops the user's reference to the
+# export, but the export may still stay around after this command returns until
+# the shutdown of the export has completed.
+#
+# @id: Block export id.
+#
+# @mode: Mode of command operation. See @BlockExportRemoveMode description.
+#        Default is 'safe'.
+#
+# Returns: Error if the export is not found or @mode is 'safe' and the export
+#          is still in use (e.g. by existing client connections)
+#
+# Since: 5.2
+##
+{ 'command': 'block-export-del',
+  'data': { 'id': 'str', '*mode': 'BlockExportRemoveMode' } }
+
+##
+# @BLOCK_EXPORT_DELETED:
+#
+# Emitted when a block export is removed and its id can be reused.
+#
+# @id: Block export id.
+#
+# Since: 5.2
+##
+{ 'event': 'BLOCK_EXPORT_DELETED',
+  'data': { 'id': 'str' } }
+
+##
+# @BlockExportInfo:
+#
+# Information about a single block export.
+#
+# @id: The unique identifier for the block export
+#
+# @type: The block export type
+#
+# @node-name: The node name of the block node that is exported
+#
+# @shutting-down: True if the export is shutting down (e.g. after a
+#                 block-export-del command, but before the shutdown has
+#                 completed)
+#
+# Since:  5.2
+##
+{ 'struct': 'BlockExportInfo',
+  'data': { 'id': 'str',
+            'type': 'BlockExportType',
+            'node-name': 'str',
+            'shutting-down': 'bool' } }
+
+##
+# @query-block-exports:
+#
+# Returns: A list of BlockExportInfo describing all block exports
+#
+# Since: 5.2
+##
+{ 'command': 'query-block-exports', 'returns': ['BlockExportInfo'] }