Old qemu versions required that 1st s/g entry is the header.
Since QEMU 1.5, patchset titled "virtio-net: iovec handling cleanup"
removed this limitation but a feature bit is needed so guests know it's
safe to lay out header differently.
This patch applies on top and adds such a feature bit to QEMU.
It is set by default for virtio-net.
virtio net header inline with the data is beneficial
for latency and small packet bandwidth - guest driver
code utilizing this feature has been acked but missed 3.11
by a narrow margin, it's pending for 3.12.
This feature bit is cleared by default when compatibility with old
machine types is requested.
Other performance-sensitive devices (blk and scsi)
don't yet support arbitrary s/g layouts, so
we only set this bit for virtio-net for now.
There are plans to allow arbitrary layouts there, but
no code has been posted yet.
Cc: Rusty Russell <rusty@rustcorp.com.au>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Virtio-net driver currently negotiates network offloads
on startup via features mechanism and have no ability to
disable and re-enable offloads later.
This patch introduced a new control command that allows
to configure device network offloads state dynamically.
The patch also introduces a new feature flag
VIRTIO_NET_F_CTRL_GUEST_OFFLOADS.
Signed-off-by: Dmitry Fleytman <dfleytma@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Message-id: 20130520081814.GA8162@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This adds virtio_net_set_netclient_name, which is used to set the
name and type shown in "info network" command.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Message-id: 1368619970-23892-2-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony 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: KONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1365690602-22729-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Create virtio-net-device which extends virtio-device, so it can be connected on
virtio-bus.
Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1365690602-22729-3-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.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: Paolo Bonzini <pbonzini@redhat.com>
