Re: [RFC v3 8/8] vhost-vdpa: introduce vhost-vdpa net client

[Cindy Lu <lulu@redhat.com>]

Hi Jason,

On Wed, Jun 3, 2020 at 2:39 PM Jason Wang <jasowang@redhat.com> wrote:
>
>
> On 2020/5/29 下午10:06, Cindy Lu wrote:
> > From: Tiwei Bie <tiwei.bie@intel.com>
>
>
> Similar for this patch, you can change the git author and keep sobs for
> both Tiwei and Ling Shan.
>
>
Will Fix this

> >
> > This patch set introduces a new net client type: vhost-vdpa.
> > vhost-vdpa net client will set up a vDPA device which is specified
> > by a "vhostdev" parameter.
> >
> > Co-authored-by: Lingshan Zhu <lingshan.zhu@intel.com>
> > Signed-off-by: Cindy Lu <lulu@redhat.com>
> > ---
> >   include/net/vhost-vdpa.h |  19 ++++
> >   include/net/vhost_net.h  |   2 +-
> >   net/Makefile.objs        |   2 +-
> >   net/clients.h            |   2 +
> >   net/net.c                |   3 +
> >   net/vhost-vdpa.c         | 235 +++++++++++++++++++++++++++++++++++++++
> >   qapi/net.json            |  26 ++++-
> >   7 files changed, 285 insertions(+), 4 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..6ce0d04f72
> > --- /dev/null
> > +++ b/include/net/vhost-vdpa.h
> > @@ -0,0 +1,19 @@
> > +/*
> > + * vhost-vdpa.h
> > + *
> > + * Copyright(c) 2017-2018 Intel Corporation.
> > + * Copyright(c) 2020 Red Hat, Inc.
> > + *
> > + * 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 56e67fe164..0b87d3c6e9 100644
> > --- a/include/net/vhost_net.h
> > +++ b/include/net/vhost_net.h
> > @@ -41,4 +41,4 @@ uint64_t vhost_net_get_acked_features(VHostNetState *net);
> >
> >   int vhost_net_set_mtu(struct vhost_net *net, uint16_t mtu);
> >   int vhost_net_get_device_id(struct vhost_net *net, uint32_t *device_id);
> > -endif
> > +#endif
> > diff --git a/net/Makefile.objs b/net/Makefile.objs
> > index c5d076d19c..5ab45545db 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_NET_VDPA) += vhost-vdpa.o
> >   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 599fb61028..82624ea9ac 100644
> > --- a/net/net.c
> > +++ b/net/net.c
> > @@ -965,6 +965,9 @@ static int (* const net_client_init_fun[NET_CLIENT_DRIVER__MAX])(
> >   #ifdef CONFIG_VHOST_NET_USER
> >           [NET_CLIENT_DRIVER_VHOST_USER] = net_init_vhost_user,
> >   #endif
> > +#ifdef CONFIG_VHOST_NET_VDPA
> > +        [NET_CLIENT_DRIVER_VHOST_VDPA] = net_init_vhost_vdpa,
> > +#endif
> >   #ifdef CONFIG_L2TPV3
> >           [NET_CLIENT_DRIVER_L2TPV3]    = net_init_l2tpv3,
> >   #endif
> > diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
> > new file mode 100644
> > index 0000000000..7b98c142b5
> > --- /dev/null
> > +++ b/net/vhost-vdpa.c
> > @@ -0,0 +1,235 @@
> > +/*
> > + * vhost-vdpa.c
> > + *
> > + * Copyright(c) 2017-2018 Intel Corporation.
> > + * Copyright(c) 2020 Red Hat, Inc.
> > + *
> > + * This work is licensed under the terms of the GNU GPL, version 2 or later.
> > + * See the COPYING file in the top-level directory.
> > + *
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +#include "clients.h"
> > +#include "net/vhost_net.h"
> > +#include "net/vhost-vdpa.h"
> > +#include "hw/virtio/vhost-vdpa.h"
> > +#include "qemu/config-file.h"
> > +#include "qemu/error-report.h"
> > +#include "qemu/option.h"
> > +#include "qapi/error.h"
> > +#include <sys/ioctl.h>
> > +#include <err.h>
> > +#include "standard-headers/linux/virtio_net.h"
> > +#include "monitor/monitor.h"
> > +#include "hw/virtio/vhost.h"
> > +
> > +/* Todo:need to add the multiqueue support here */
> > +typedef struct VhostVDPAState {
> > +    NetClientState nc;
> > +    struct vhost_vdpa vhost_vdpa;
> > +    VHostNetState *vhost_net;
> > +    uint64_t acked_features;
> > +    bool started;
> > +} VhostVDPAState;
> > +
> > +VHostNetState *vhost_vdpa_get_vhost_net(NetClientState *nc)
> > +{
> > +    VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> > +    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +    return s->vhost_net;
> > +}
> > +
> > +uint64_t vhost_vdpa_get_acked_features(NetClientState *nc)
> > +{
> > +    VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> > +    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +    return s->acked_features;
> > +}
> > +
> > +static int vhost_vdpa_check_device_id(NetClientState *nc)
>
>
> A better name is needed, something like "vhost_vdpa_net_check_devie_id"
> is better.
>
Sure will fix this
>
> > +{
> > +    uint32_t device_id;
> > +    int ret;
> > +    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +    VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> > +    /* Get the device id from hw*/
>
>
> The code explains itself, so no need for this comment.
>
will remove this
>
> > +    ret = vhost_net_get_device_id(s->vhost_net, &device_id);
> > +    if (device_id != VIRTIO_ID_NET) {
> > +        return -ENOTSUP;
> > +    }
> > +    return ret;
> > +}
> > +
> > +static void vhost_vdpa_del(NetClientState *ncs)
> > +{
> > +    VhostVDPAState *s;
> > +
> > +    assert(ncs->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +
> > +    s = DO_UPCAST(VhostVDPAState, nc, ncs);
> > +
> > +    if (s->vhost_net) {
> > +        /* save acked features */
> > +        uint64_t features = vhost_net_get_acked_features(s->vhost_net);
> > +        if (features) {
> > +            s->acked_features = features;
> > +        }
>
>
> I'm not sure I get here, is the acked_features used in the
> vhost_net_cleanup()?
>
I think we can remove this part, seems these bit are not using anymore
>
> > +        vhost_net_cleanup(s->vhost_net);
> > +    }
> > +}
> > +
> > +static int vhost_vdpa_add(NetClientState *ncs, void *be)
> > +{
> > +    VhostNetOptions options;
> > +    struct vhost_net *net = NULL;
> > +    VhostVDPAState *s;
> > +    int ret;
> > +
> > +    options.backend_type = VHOST_BACKEND_TYPE_VDPA;
> > +
> > +    assert(ncs->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +
> > +    s = DO_UPCAST(VhostVDPAState, nc, ncs);
> > +
> > +    options.net_backend = ncs;
> > +    options.opaque      = be;
> > +    options.busyloop_timeout = 0;
> > +    net = vhost_net_init(&options);
> > +    if (!net) {
> > +        error_report("failed to init vhost_net for queue");
> > +        goto err;
> > +    }
> > +
> > +    if (s->vhost_net) {
> > +        vhost_net_cleanup(s->vhost_net);
> > +        g_free(s->vhost_net);
> > +    }
> > +    s->vhost_net = net;
> > +    /* check the device id for vdpa */
>
>
> The comment could be removed as well.
>
>
Sure will remove this

> > +    ret = vhost_vdpa_check_device_id(ncs);
> > +    if (ret) {
> > +        goto err;
> > +    }
> > +    return 0;
> > +err:
> > +    if (net) {
> > +        vhost_net_cleanup(net);
> > +    }
> > +    vhost_vdpa_del(ncs);
> > +    return -1;
> > +}
> > +
> > +static void vhost_vdpa_cleanup(NetClientState *nc)
> > +{
> > +    VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> > +
> > +    if (s->vhost_net) {
> > +        vhost_net_cleanup(s->vhost_net);
> > +        g_free(s->vhost_net);
> > +        s->vhost_net = NULL;
> > +    }
> > +
> > +    qemu_purge_queued_packets(nc);
>
>
> Why this is needed?
>
> Thanks
>
This is to clean the packet in the queue while the vdpa remove,  I
will double check this part
>
> > +}
> > +
> > +static bool vhost_vdpa_has_vnet_hdr(NetClientState *nc)
> > +{
> > +    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +
> > +    return true;
> > +}
> > +
> > +static bool vhost_vdpa_has_ufo(NetClientState *nc)
> > +{
> > +    assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +    VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
> > +    uint64_t  features = 0;
> > +
> > +    features |= (1ULL << VIRTIO_NET_F_HOST_UFO);
> > +    features = vhost_net_get_features(s->vhost_net, features);
> > +    return !!(features & (1ULL << VIRTIO_NET_F_HOST_UFO));
> > +
> > +}
> > +
> > +static NetClientInfo net_vhost_vdpa_info = {
> > +        .type = NET_CLIENT_DRIVER_VHOST_VDPA,
> > +        .size = sizeof(VhostVDPAState),
> > +        .cleanup = vhost_vdpa_cleanup,
> > +        .has_vnet_hdr = vhost_vdpa_has_vnet_hdr,
> > +        .has_ufo = vhost_vdpa_has_ufo,
> > +};
> > +
> > +static int net_vhost_vdpa_init(NetClientState *peer, const char *device,
> > +                               const char *name, const char *vhostdev,
> > +                               bool has_fd, char *fd)
> > +{
> > +    NetClientState *nc = NULL;
> > +    VhostVDPAState *s;
> > +    int vdpa_device_fd = -1;
> > +    Error *err = NULL;
> > +    int ret = 0;
> > +    assert(name);
> > +
> > +    nc = qemu_new_net_client(&net_vhost_vdpa_info, peer, device, name);
> > +    snprintf(nc->info_str, sizeof(nc->info_str), "vhost-vdpa");
> > +    nc->queue_index = 0;
> > +
> > +    s = DO_UPCAST(VhostVDPAState, nc, nc);
> > +
> > +    if (has_fd) {
> > +        vdpa_device_fd = monitor_fd_param(cur_mon, fd, &err);
> > +    } else{
> > +        vdpa_device_fd = open(vhostdev, O_RDWR);
> > +    }
> > +
> > +    if (vdpa_device_fd == -1) {
> > +        return -errno;
> > +    }
> > +    s->vhost_vdpa.device_fd = vdpa_device_fd;
> > +    ret = vhost_vdpa_add(nc, (void *)&s->vhost_vdpa);
> > +    assert(s->vhost_net);
> > +
> > +    if (ret) {
> > +        if (has_fd) {
> > +            close(vdpa_device_fd);
> > +        }
> > +    }
> > +    return ret;
> > +}
> > +
> > +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;
> > +    }
> > +
> > +    return 0;
> > +}
> > +
> > +int net_init_vhost_vdpa(const Netdev *netdev, const char *name,
> > +                        NetClientState *peer, Error **errp)
> > +{
> > +    const NetdevVhostVDPAOptions *opts;
> > +
> > +    assert(netdev->type == NET_CLIENT_DRIVER_VHOST_VDPA);
> > +    opts = &netdev->u.vhost_vdpa;
> > +    /* verify net frontend */
> > +    if (qemu_opts_foreach(qemu_find_opts("device"), net_vhost_check_net,
> > +                          (char *)name, errp)) {
> > +        return -1;
> > +    }
> > +    return net_vhost_vdpa_init(peer, "vhost_vdpa", name, opts->vhostdev,
> > +                    opts->has_fd, opts->fd);
> > +}
> > diff --git a/qapi/net.json b/qapi/net.json
> > index cebb1b52e3..37507ce9ba 100644
> > --- a/qapi/net.json
> > +++ b/qapi/net.json
> > @@ -428,6 +428,27 @@
> >       '*vhostforce':    'bool',
> >       '*queues':        'int' } }
> >
> > +##
> > +# @NetdevVhostVDPAOptions:
> > +#
> > +# Vhost-vdpa network backend
> > +#
> > +# @vhostdev: name of a vdpa dev path in sysfs
> > +#            (default path:/dev/vhost-vdpa-$ID)
> > +#
> > +# @fd: file descriptor of an already opened vdpa device
> > +#
> > +# @queues: number of queues to be created for multiqueue vhost-vdpa
> > +#          (default: 1)
> > +#
> > +# Since: 5.1
> > +##
> > +{ 'struct': 'NetdevVhostVDPAOptions',
> > +  'data': {
> > +    '*vhostdev':     'str',
> > +    '*fd':           'str',
> > +    '*queues':       'int' } }
> > +
> >   ##
> >   # @NetClientDriver:
> >   #
> > @@ -437,7 +458,7 @@
> >   ##
> >   { 'enum': 'NetClientDriver',
> >     'data': [ 'none', 'nic', 'user', 'tap', 'l2tpv3', 'socket', 'vde',
> > -            'bridge', 'hubport', 'netmap', 'vhost-user' ] }
> > +            'bridge', 'hubport', 'netmap', 'vhost-user', 'vhost-vdpa' ] }
> >
> >   ##
> >   # @Netdev:
> > @@ -465,7 +486,8 @@
> >       'bridge':   'NetdevBridgeOptions',
> >       'hubport':  'NetdevHubPortOptions',
> >       'netmap':   'NetdevNetmapOptions',
> > -    'vhost-user': 'NetdevVhostUserOptions' } }
> > +    'vhost-user': 'NetdevVhostUserOptions',
> > +    'vhost-vdpa': 'NetdevVhostVDPAOptions' } }
> >
> >   ##
> >   # @NetLegacy:
>