Re: [PATCH v5 05/12] qapi: net: add stream and dgram netdevs

[Markus Armbruster <armbru@redhat.com>]

Laurent Vivier <lvivier@redhat.com> writes:

> Copied from socket netdev file and modified to use SocketAddress
> to be able to introduce new features like unix socket.
>
> "udp" and "mcast" are squashed into dgram netdev, multicast is detected
> according to the IP address type.
> "listen" and "connect" modes are managed by stream netdev. An optional
> parameter "server" defines the mode (server by default)
>
> Signed-off-by: Laurent Vivier <lvivier@redhat.com>
> Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
> ---

[...]

> diff --git a/qapi/net.json b/qapi/net.json
> index d6f7cfd4d656..32a9b1a5ac6c 100644
> --- a/qapi/net.json
> +++ b/qapi/net.json
> @@ -7,6 +7,7 @@
>  ##
>  
>  { 'include': 'common.json' }
> +{ 'include': 'sockets.json' }
>  
>  ##
>  # @set_link:
> @@ -566,6 +567,42 @@
>      '*isolated':  'bool' },
>    'if': 'CONFIG_VMNET' }
>  
> +##
> +# @NetdevStreamOptions:
> +#
> +# Configuration info for stream socket netdev
> +#
> +# @addr: socket address to listen on (server=true)
> +#        or connect to (server=false)

Only some address types are valid, as discussed in review of v4.
Shouldn't we document that here?

> +# @server: create server socket (default: true)
> +#
> +# Since: 7.1
> +##
> +{ 'struct': 'NetdevStreamOptions',
> +  'data': {
> +    'addr':   'SocketAddress',
> +    '*server': 'bool' } }
> +
> +##
> +# @NetdevDgramOptions:
> +#
> +# Configuration info for datagram socket netdev.
> +#
> +# @remote: remote address
> +# @local: local address
> +#
> +# The code checks there is at least one of these options and reports an error
> +# if not. If remote address is present and it's a multicast address, local
> +# address is optional. Otherwise local address is required and remote address
> +# is optional.
> +#
> +# Since: 7.1
> +##
> +{ 'struct': 'NetdevDgramOptions',
> +  'data': {
> +    '*local':  'SocketAddress',
> +    '*remote': 'SocketAddress' } }

Hard to see, but the space in "} }" is funny: it's U+00A0
(NO-BREAK-SPACE) encoded in UTF-8.  Make it a plain old space, please.

Only some combinations of address types are valid, as discussed in
review of v4.  Shouldn't we document that here?

> +
>  ##
>  # @NetClientDriver:
>  #
> @@ -579,8 +616,9 @@
>  #        @vmnet-bridged since 7.1
>  ##
>  { 'enum': 'NetClientDriver',
> -  'data': [ 'none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'vde',
> -            'bridge', 'hubport', 'netmap', 'vhost-user', 'vhost-vdpa',
> +  'data': [ 'none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'stream',
> +            'dgram', 'vde', 'bridge', 'hubport', 'netmap', 'vhost-user',
> +            'vhost-vdpa',
>              { 'name': 'vmnet-host', 'if': 'CONFIG_VMNET' },
>              { 'name': 'vmnet-shared', 'if': 'CONFIG_VMNET' },
>              { 'name': 'vmnet-bridged', 'if': 'CONFIG_VMNET' }] }
> @@ -610,6 +648,8 @@
>      'tap':      'NetdevTapOptions',
>      'l2tpv3':   'NetdevL2TPv3Options',
>      'socket':   'NetdevSocketOptions',
> +    'stream':   'NetdevStreamOptions',
> +    'dgram':    'NetdevDgramOptions',
>      'vde':      'NetdevVdeOptions',
>      'bridge':   'NetdevBridgeOptions',
>      'hubport':  'NetdevHubPortOptions',
> diff --git a/qemu-options.hx b/qemu-options.hx
> index 377d22fbd82f..2be0cbd2549b 100644
> --- a/qemu-options.hx
> +++ b/qemu-options.hx
> @@ -2722,6 +2722,18 @@ DEF("netdev", HAS_ARG, QEMU_OPTION_netdev,
>      "-netdev socket,id=str[,fd=h][,udp=host:port][,localaddr=host:port]\n"
>      "                configure a network backend to connect to another network\n"
>      "                using an UDP tunnel\n"
> +    "-netdev stream,id=str[,server=on|off],addr.type=inet,addr.host=host,addr.port=port\n"
> +    "-netdev stream,id=str[,server=on|off],addr.type=fd,addr.str=h\n"
> +    "                configure a network backend to connect to another network\n"
> +    "                using a socket connection in stream mode.\n"
> +    "-netdev dgram,id=str,remote.type=inet,remote.host=maddr,remote.port=port[,local.type=inet,local.host=addr]\n"
> +    "-netdev dgram,id=str,remote.type=inet,remote.host=maddr,remote.port=port[,local.type=fd,local.str=h]\n"
> +    "                configure a network backend to connect to a multicast maddr and port\n"
> +    "                use 'local.host=addr' to specify the host address to send packets from\n"

I think we use ``local.host=addr`` markup.

> +    "-netdev dgram,id=str,local.type=inet,local.host=addr,local.port=port[,remote.type=inet,remote.host=addr,remote.port=port]\n"
> +    "-netdev dgram,id=str,local.type=fd,local.str=h\n"
> +    "                configure a network backend to connect to another network\n"
> +    "                using an UDP tunnel\n"
>  #ifdef CONFIG_VDE
>      "-netdev vde,id=str[,sock=socketpath][,port=n][,group=groupname][,mode=octalmode]\n"
>      "                configure a network backend to connect to port 'n' of a vde switch\n"

I intend to look at this again after we decide what to do about the doc
comments in net.json.