A new vhost user message is added to allow QEMU to ask to vhost user backend to
broadcast a fake RARP after live migration for guest without GUEST_ANNOUNCE
capability.

This new message is sent only if the backend supports the new
VHOST_USER_PROTOCOL_F_RARP protocol feature.
The payload of this new message is the MAC address of the guest (not known by
the backend). The MAC address is copied in the first 6 bytes of a u64 to avoid
to create a new payload message type.

This new message has no equivalent ioctl so a new callback is added in the
userOps structure to send the request.

Upon reception of this new message the vhost user backend must generate and
broadcast a fake RARP request to notify the migration is terminated.
Signed-off-by: NThibaut Collet <thibaut.collet@6wind.com>
[Rebased and fixed checkpatch errors - Marc-André]
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Tested-by: NThibaut Collet <thibaut.collet@6wind.com>

Some vhost user backends are able to support live migration.
To provide this service the following features must be added:
1. Add the VIRTIO_NET_F_GUEST_ANNOUNCE capability to vhost-net when netdev
   backend is vhost-user.
2. Provide a nop receive callback to vhost-user.
   This callback is called by:
    *  qemu_announce_self after a migration to send fake RARP to avoid network
       outage for peers talking to the migrated guest.
         - For guest with GUEST_ANNOUNCE capabilities, guest already sends GARP
           when the bit VIRTIO_NET_S_ANNOUNCE is set.
           => These packets must be discarded.
         - For guest without GUEST_ANNOUNCE capabilities, migration termination
           is notified when the guest sends packets.
           => These packets can be discarded.
    * virtio_net_tx_bh with a dummy boot to send fake bootp/dhcp request.
      BIOS guest manages virtio driver to send 4 bootp/dhcp request in case of
      dummy boot.
      => These packets must be discarded.
Signed-off-by: NThibaut Collet <thibaut.collet@6wind.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Tested-by: NThibaut Collet <thibaut.collet@6wind.com>

Replace error_report() and use tracing instead. It's not an error to get
a connection or a disconnection, so silence this and trace it instead.
Signed-off-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Tested-by: NThibaut Collet <thibaut.collet@6wind.com>

This patch is initially based a patch from Nikolay Nikolaev.

This patch adds vhost-user multiple queue support, by creating a nc
and vhost_net pair for each queue.

Qemu exits if find that the backend can't support the number of requested
queues (by providing queues=# option). The max number is queried by a
new message, VHOST_USER_GET_QUEUE_NUM, and is sent only when protocol
feature VHOST_USER_PROTOCOL_F_MQ is present first.

The max queue check is done at vhost-user initiation stage. We initiate
one queue first, which, in the meantime, also gets the max_queues the
backend supports.

In older version, it was reported that some messages are sent more times
than necessary. Here we came an agreement with Michael that we could
categorize vhost user messages to 2 types: non-vring specific messages,
which should be sent only once, and vring specific messages, which should
be sent per queue.

Here I introduced a helper function vhost_user_one_time_request(), which
lists following messages as non-vring specific messages:

        VHOST_USER_SET_OWNER
        VHOST_USER_RESET_DEVICE
        VHOST_USER_SET_MEM_TABLE
        VHOST_USER_GET_QUEUE_NUM

For above messages, we simply ignore them when they are not sent the first
time.
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: NChangchun Ouyang <changchun.ouyang@intel.com>
Signed-off-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NYuanhan Liu <yuanhan.liu@linux.intel.com>
Reviewed-by: NJason Wang <jasowang@redhat.com>
Tested-by: NMarcel Apfelbaum <marcel@redhat.com>

This reverts commit 830d70db.

The interface isn't fully backwards-compatible, which is bad.
Let's redo this properly after 2.4.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

We use vhostforce to enable vhost even if Guests don't have MSI-X
support and we fall back to QEMU virtio-net.

This gives a very small performance gain, but the disadvantage
is that guest now controls which virtio code is running
(qemu or vhost) so our attack surface is doubled.

This patch will enable vhost unconditionally whenever it's requested.
For compatibility, enable vhost when vhostforce is set, as well.
Signed-off-by: NPankaj Gupta <pagupta@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Reviewed-by: NJason Wang <jasowang@redhat.com>

When -netdev vhost-user fails, it first reports a specific error, then
one or more generic ones, like this:

    $ qemu-system-x86_64 -netdev vhost-user,id=foo,chardev=xxx
    qemu-system-x86_64: -netdev vhost-user,id=foo,chardev=xxx: chardev "xxx" not found
    qemu-system-x86_64: -netdev vhost-user,id=foo,chardev=xxx: No suitable chardev found
    qemu-system-x86_64: -netdev vhost-user,id=foo,chardev=xxx: Device 'vhost-user' could not be initialized

With the command line, the messages go to stderr.  In HMP, they go to
the monitor.  In QMP, the last one becomes the error reply, and the
others go to stderr.

Convert net_init_vhost_user() and its helpers to Error.  This
suppresses the unwanted unspecific error messages, and makes the
specific error the QMP error reply.

Cc: Stefan Hajnoczi <stefanha@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>

Retain the function value for now, to permit selective conversion of
its callers.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

When the argument is non-zero, qemu_opt_foreach() stops on callback
returning non-zero, and returns that value.

When the argument is zero, it doesn't stop, and returns the callback's
value from the last iteration.

The two callers that pass zero could just as well pass one:

* qemu_spice_init()'s callback add_channel() either returns zero or
  exit()s.

* config_write_opts()'s callback config_write_opt() always returns
  zero.

Drop the parameter, and always stop.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Retain the function value for now, to permit selective conversion of
its callers.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Acked-by: NKevin Wolf <kwolf@redhat.com>

When the argument is non-zero, qemu_opts_foreach() stops on callback
returning non-zero, and returns that value.

When the argument is zero, it doesn't stop, and returns the bit-wise
inclusive or of all the return values.  Funky :)

The callers that pass zero could just as well pass one, because their
callbacks can't return anything but zero:

* qemu_add_globals()'s callback qdev_add_one_global()

* qemu_config_write()'s callback config_write_opts()

* main()'s callbacks default_driver_check(), drive_enable_snapshot(),
  vnc_init_func()

Drop the parameter, and always stop.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Acked-by: NKevin Wolf <kwolf@redhat.com>

Based on patch by Nikolay Nikolaev:
Vhost-user will implement the multi queue support in a similar way
to what vhost already has - a separate thread for each queue.
To enable the multi queue functionality - a new command line parameter
"queues" is introduced for the vhost-user netdev.
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Signed-off-by: NChangchun Ouyang <changchun.ouyang@intel.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Error reporting for netdev_add is broken: the net_client_init_fun[]
report the actual errors with (at best) error_report(), and their
caller net_client_init1() makes up a generic error on top.

For command line and HMP, this produces an mildly ugly error cascade.

In QMP, the actual errors go to stderr, and the generic error becomes
the command's error reply.

To fix this, we need to convert the net_client_init_fun[] to Error.

To permit fixing them one by one, add an Error ** parameter to the
net_client_init_fun[].  If the call fails without returning an Error,
make up the same generic Error as before.  But if it returns one, use
that instead.  Since none of them does so far, no functional change.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-id: 1431691143-1015-3-git-send-email-armbru@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Signed-off-by: NGonglei <arei.gonglei@huawei.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMichael Tokarev <mjt@tls.msk.ru>

Currently, vhost user nic doesn't support non msi guests(like pxe stage) by default.
Vhost user nic can't fall back to qemu like normal vhost net nic does. So we should
enable it for non msi guests.
Signed-off-by: NHaifeng Gao <gaohaifeng.gao@huawei.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

The supplied chardev id will be inspected for supported options. Only
a socket backend, with a set path (i.e. a Unix socket) and optionally
the server parameter set, will be allowed. Other options (nowait, telnet)
will make the chardev unusable and the netdev will not be initialised.

Additional checks for validity:
  - requires `-numa node,memdev=..`
  - requires `-device virtio-net-*`

The `vhostforce` option is used to force vhost-net when we deal with
non-MSIX guests.
Signed-off-by: NAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NLuiz Capitulino <lcapitulino@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Add a new QEMU netdev backend that is intended to invoke vhost_net with the
vhost-user backend. It uses an Unix socket chardev to establish a
communication with the 'slave' (client and server mode supported).

At runtime the netdev will handle OPEN/CLOSE events from the chardev. Upon
disconnection it will set link_down accordingly and notify virtio-net; the
virtio-net interface will go down.
Signed-off-by: NAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: NNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>