Re: [RFC v1 2/4] vhost-vdpa: introduce vhost-vdpa net client

[Cindy Lu <lulu@redhat.com>]

On Tue, Apr 21, 2020 at 11:47 PM Laurent Vivier <lvivier@redhat.com> wrote:
>
> On 20/04/2020 11:32, Cindy Lu wrote:
> > This patch set introduces a new net client type: vhost-vdpa.
> > vhost-vdpa net client will set up a vDPA device which is svhostdevpecified
> > by a "vhostdev" parameter.
> >
> > Author: Tiwei Bie
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
> > ---
> >  include/net/vhost-vdpa.h |  18 ++++
> >  include/net/vhost_net.h  |   1 +
> >  net/Makefile.objs        |   2 +-
> >  net/clients.h            |   2 +
> >  net/net.c                |   1 +
> >  net/vhost-vdpa.c         | 211 +++++++++++++++++++++++++++++++++++++++
> >  qapi/net.json            |  21 +++-
> >  7 files changed, 253 insertions(+), 3 deletions(-)
> >  create mode 100644 include/net/vhost-vdpa.h
> >  create mode 100644 net/vhost-vdpa.c
> >
> > diff --git a/include/net/vhost-vdpa.h b/include/net/vhost-vdpa.h
> > new file mode 100644
> > index 0000000000..9ddd538dad
> > --- /dev/null
> > +++ b/include/net/vhost-vdpa.h
> > @@ -0,0 +1,18 @@
> > +/*
> > + * vhost-vdpa.h
> > + *
> > + * Copyright(c) 2017 Intel Corporation. All rights reserved.
> > + *
> > + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> > + * See the COPYING file in the top-level directory.
> > + *
> > + */
> > +
> > +#ifndef VHOST_VDPA_H
> > +#define VHOST_VDPA_H
> > +
> > +struct vhost_net;
> > +struct vhost_net *vhost_vdpa_get_vhost_net(NetClientState *nc);
> > +uint64_t vhost_vdpa_get_acked_features(NetClientState *nc);
> > +
> > +#endif /* VHOST_VDPA_H */
> > diff --git a/include/net/vhost_net.h b/include/net/vhost_net.h
> > index 77e47398c4..6f3a624cf7 100644
> > --- a/include/net/vhost_net.h
> > +++ b/include/net/vhost_net.h
> > @@ -39,5 +39,6 @@ int vhost_set_vring_enable(NetClientState * nc, int enable);
> >  uint64_t vhost_net_get_acked_features(VHostNetState *net);
> >
> >  int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu);
> > +int vhost_set_state(NetClientState *nc, int state);
> >
> >  #endif
> > diff --git a/net/Makefile.objs b/net/Makefile.objs
> > index c5d076d19c..da459cfc19 100644
> > --- a/net/Makefile.objs
> > +++ b/net/Makefile.objs
> > @@ -26,7 +26,7 @@ tap-obj-$(CONFIG_SOLARIS) = tap-solaris.o
> >  tap-obj-y ?= tap-stub.o
> >  common-obj-$(CONFIG_POSIX) += tap.o $(tap-obj-y)
> >  common-obj-$(CONFIG_WIN32) += tap-win32.o
> > -
> > +common-obj-$(CONFIG_VHOST_KERNEL) += vhost-vdpa.o
>
> should it be CONFIG_VHOST_NET_USER as you use net_init_vhost_vdpa()
> below inside a "#ifdef CONFIG_VHOST_NET_USER"?
>
> Why don't you define a CONFIG_VHOST_VDPA?
>
Thanks Laurent for point it out,  There is no dependence between
CONFIG_VHOST_NET_USER and vDPA,
So I will implement a new macro specific for vDPA

> >  vde.o-libs = $(VDE_LIBS)
> >
> >  common-obj-$(CONFIG_CAN_BUS) += can/
> > diff --git a/net/clients.h b/net/clients.h
> > index a6ef267e19..92f9b59aed 100644
> > --- a/net/clients.h
> > +++ b/net/clients.h
> > @@ -61,4 +61,6 @@ int net_init_netmap(const Netdev *netdev, const char *name,
> >  int net_init_vhost_user(const Netdev *netdev, const char *name,
> >                          NetClientState *peer, Error **errp);
> >
> > +int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
> > +                        NetClientState *peer, Error **errp);
> >  #endif /* QEMU_NET_CLIENTS_H */
> > diff --git a/net/net.c b/net/net.c
> > index ac5080dda1..2beb95388a 100644
> > --- a/net/net.c
> > +++ b/net/net.c
> > @@ -964,6 +964,7 @@ static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
> >          [NET_CLIENT_DRIVER_HUBPORT]   = net_init_hubport,
> >  #ifdef CONFIG_VHOST_NET_USER          ^^^^^^^^^^^^^^^^^^^^^
>                    here
>
> >          [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
> > +        [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
> >  #endif
> >  #ifdef CONFIG_L2TPV3
> >          [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
> > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> > new file mode 100644
> > index 0000000000..5daeba0b76
> > --- /dev/null
> > +++ b/net/vhost-vdpa.c
> ...
> > +static int net_vhost_check_net(void *opaque, QemuOpts *opts, Error **errp)
> > +{
> > +    const char *name = opaque;
> > +    const char *driver, *netdev;
> > +
> > +    driver = qemu_opt_get(opts, "driver");
> > +    netdev = qemu_opt_get(opts, "netdev");
> > +
> > +    if (!driver || !netdev) {
> > +        return 0;
> > +    }
> > +
> > +    if (strcmp(netdev, name) == 0 &&
> > +        !g_str_has_prefix(driver, "virtio-net-")) {
> > +        error_setg(errp, "vhost-vdpa requires frontend driver virtio-net-*");
> > +        return -1;
> > +    }
> >
>
> So perhaps you can build the file only if CONFIG_VIRTIO_NET is set?
>
> Thanks,
> Laurent
>
Thanks, There will be a new macro specific for vDPA