Commit 32993698 (vhost: disable on tap link down) tries to disable the vhost
also when the peer's link is down. But the check was not done properly, the
vhost were only started when:

1) peer's link is not down
2) virtio-net has already been started.

Since == have a higher precedence than &&, place a brace to make sure both the
conditions were met then does the check. This fixes the crash when doing a savem
after set the link off which let qemu crash and complains:

virtio_net_save: Assertion `!n->vhost_started' failed.

Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Message-id: 1366972060-21606-1-git-send-email-jasowang@redhat.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Commit 14f9b664 (hw/virtio-net.c: set config size using host features) tries to
calculate config size based on the host features. But it forgets the
VIRTIO_NET_F_MAC were always set for qemu later. This will lead a zero config
len for virtio-net device when both VIRTIO_NET_F_STATUS and VIRTIO_NET_F_MQ were
disabled form command line. Then qemu will crash when user tries to read the
config of virtio-net.

Fix this by counting VIRTIO_NET_F_MAC and make sure the config at least contains
the mac address.

Cc: Jesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Message-id: 1366874814-2658-1-git-send-email-jasowang@redhat.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Multiqueue patchset conditionally add control vq only when guest negotiate the
feature. Though the spec is not clear on this but it breaks the minix guest
since it will identify the ctrl vq even if it does not support it. Though this
behavior seems a violation on the spec "If the VIRTIO_NET_F_CTRL_VQ feature bit
is negotiated, identify the control virtqueue.", to keep the backward
compatibility, always add the ctrl vq at end of the queues.
Reported-by: NAurelien Jarno <aurelien@aurel32.net>
Acked-by: NMichael S. Tsirkin <mst@redhat.com>
Tested-by: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Message-id: 1366874663-2566-1-git-send-email-jasowang@redhat.com
Cc: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This clean the init and the exit functions and rename virtio_common_cleanup
to virtio_cleanup.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This remove the function pointer in VirtIODevice, and use only
VirtioDeviceClass function pointer.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1366791683-5350-5-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This remove old init and exit function as they are no longer needed.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1365690602-22729-8-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

As the virtio-net-pci and virtio-net-s390 are switched to the new API,
we can use QOM casts.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1365690602-22729-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Create virtio-net-device which extends virtio-device, so it can be connected on
virtio-bus.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: NCornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1365690602-22729-3-git-send-email-fred.konrad@greensocs.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Many of these should be cleaned up with proper qdev-/QOM-ification.
Right now there are many catch-all headers in include/hw/ARCH depending
on cpu.h, and this makes it necessary to compile these files per-target.
However, fixing this does not belong in these patches.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Following commit 921ac5d0 (virtio-net:
remove layout assumptions for ctrl vq), this patch makes multiqueue ctrl
handling not rely on the layout of descriptors.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

These structures must be made public to avoid two memory allocations for
refactored virtio devices.
Signed-off-by: NKONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: NAndreas Färber <afaerber@suse.de>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAndreas Färber <afaerber@suse.de>
Message-id: 1363624648-16906-2-git-send-email-fred.konrad@greensocs.com

Changes V4 <- V3:
   * Rebased on current git.

Changes V3 <- V2:
    * Style correction spotted by Andreas (virtio-scsi.h).
    * Style correction for virtio-net.h.

Changes V2 <- V1:
    * Move the dataplane include into the header (virtio-blk).
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Done with this script:

cd hw
for i in `find . -name '*.h' | sed 's/^..//'`; do
  echo '\,^#.*include.*["<]'$i'[">], s,'$i',hw/&,'
done | sed -i -f - `find . -type f`

This is so that paths remain valid as files are moved.

Instead, files in hw/dataplane are referenced with the relative path.
We know they are not going to move to include/, and they are the only
include files that are in subdirectories _and_ move.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Edivaldo reports a problem that the array of NetClientState in NICState is too
large - MAX_QUEUE_NUM(1024) which will wastes memory even if multiqueue is not
used.

Instead of static arrays, solving this issue by allocating the queues on demand
for both the NetClientState array in NICState and VirtIONetQueue array in
VirtIONet.

Tested by myself, with single virtio-net-pci device. The memory allocation is
almost the same as when multiqueue is not merged.

Cc: Edivaldo de Araujo Pereira <edivaldoapereira@yahoo.com.br>
Cc: qemu-stable@nongnu.org
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Currently, the config size for virtio devices is hard coded. When a new
feature is added that changes the config size, drivers that assume a static
config size will break. For purposes of backward compatibility, there needs
to be a way to inform drivers of the config size needed to accommodate the
set of features enabled.

aliguori: merged in
 - hw/virtio-net: use existing macros to implement endof
 - hw/virtio-net: fix config_size data type
Signed-off-by: NJesse Larrew <jlarrew@linux.vnet.ibm.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This patch add migration support for multiqueue virtio-net. Instead of bumping
the version, we conditionally send the info of multiqueue only when the device
support more than one queue to maintain the backward compatibility.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This patch implements both userspace and vhost support for multiple queue
virtio-net (VIRTIO_NET_F_MQ). This is done by introducing an array of
VirtIONetQueue to VirtIONet.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

To support multiqueue virtio-net, the first step is to separate the virtqueue
related fields from VirtIONet to a new structure VirtIONetQueue. The following
patches will add an array of VirtIONetQueue to VirtIONet based on this patch.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This patch lets vhost support multiqueue. The idea is simple, just launching
multiple threads of vhost and let each of vhost thread processing a subset of
the virtqueues of the device. After this change each emulated device can have
multiple vhost threads as its backend.

To do this, a virtqueue index were introduced to record to first virtqueue that
will be handled by this vhost_net device. Based on this and nvqs, vhost could
calculate its relative index to setup vhost_net device.

Since we may have many vhost/net devices for a virtio-net device. The setting of
guest notifiers were moved out of the starting/stopping of a specific vhost
thread. The vhost_net_{start|stop}() were renamed to
vhost_net_{start|stop}_one(), and a new vhost_net_{start|stop}() were introduced
to configure the guest notifiers and start/stop all vhost/vhost_net devices.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

To support multiqueue nic, this patch separate the nic destructor from
qemu_del_net_client() to a new helper qemu_del_nic() since the mapping bettween
NiCState and NetClientState were not 1:1 in multiqueue. The following patches
would refactor this function to support multiqueue nic.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

To support multiqueue, this patch introduces a helper qemu_get_nic() to get
NICState from a NetClientState. The following patches would refactor this helper
to support multiqueue.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

To support multiqueue, the patch introduce a helper qemu_get_queue()
which is used to get the NetClientState of a device. The following patches would
refactor this helper to support multiqueue.
Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Signed-off-by: NJason Wang <jasowang@redhat.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This patch makes rx commands consistent with specification.
Signed-off-by: NAmos Kong <akong@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

In virtio-net guest driver, currently we write MAC address to
pci config space byte by byte, this means that we have an
intermediate step where mac is wrong. This patch introduced
a new control command to set MAC address, it's atomic.

VIRTIO_NET_F_CTRL_MAC_ADDR is a new feature bit for compatibility.

"mac" field will be set to read-only when VIRTIO_NET_F_CTRL_MAC_ADDR
is acked.
Signed-off-by: NAmos Kong <akong@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Virtio-net code makes assumption about virtqueue descriptor layout
(e.g. sg[0] is the header, sg[1] is the data buffer).

This patch makes code not rely on the layout of descriptors.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NAmos Kong <akong@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Once guest overrides virtio net primary mac,
it retains the value set until qemu exit.
This is inconsistent with standard nic behaviour.
To fix, revert the mac to the original value on reset.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Support backend guest notifier masking in vhost-net:
create eventfd at device init, when masked,
make vhost use that as eventfd instead of
sending an interrupt.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

As vhost started is cleared last thing on stop,
set it first things on start. This makes it
possible to use vhost_started while start is in
progress which is used by follow-up patches.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move public headers to include/net, and leave private headers in net/.
Put the virtio headers in include/net/tap.h, removing the multiple copies
that existed.  Leave include/net/tap.h as the interface for NICs, and
net/tap_int.h as the interface for OS-specific parts of the tap backend.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Modern linux supports arbitrary header size,
which makes it possible to pass mrg buf header
to tap directly without iovec mangling.
Use this capability when it is there.

This removes the need to deal with it in
vhost-net as we do now.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

There's no reason to query header support at random
times: at load or feature query.
Driver also might not query functions.
Cleaner to do it at device init.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

During packet filtering, we can now use host hdr len
to offset incoming buffer unconditionally.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Remove code duplication using guest header length that we track.
Drop specific layout requirement for rx buffers: things work
using generic iovec functions in any case.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Avoid mangling iovec manually: use safe iov_*
functions.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

We know offset is 0, assert that.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Now that we know host hdr length, we don't need to
duplicate the logic in receive_hdr: caller can
figure out the offset itself.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>

Avoid magling iov manually: use safe iov operations
for processing packets incoming to guest.
This also removes the requirement for virtio header to
fit the first s/g entry exactly.
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>