The VIRTIO 1.0 specification added the DEVICE_NEEDS_RESET device status
bit in "VIRTIO-98: Add DEVICE_NEEDS_RESET". This patch defines the
device status bit in the uapi header file so that both the kernel and
userspace applications can use it.
The bit is currently unused by the virtio guest drivers and vhost.
According to the spec "a good implementation will try to recover by
issuing a reset". This is not attempted here because it requires
auditing the virtio drivers to ensure there are no resource leaks or
crashes if the device needs to be reset mid-operation.
See "2.1 Device Status Field" in the VIRTIO 1.0 specification for
details.
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The VIRTIO_F_ANY_LAYOUT and VIRTIO_F_NOTIFY_ON_EMPTY features are pre-1.0
only.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Based on original patches by Rusty Russell, Thomas Huth
and Cornelia Huck.
Note: at this time, we do not negotiate this feature bit
in core, drivers have to declare VERSION_1 support explicitly.
For this reason we treat this bit as a device bit
and not as a transport bit for now.
After all drivers are converted, we will be able to
move VERSION_1 to core and drop it from all drivers.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Michael Kerrisk <mtk.manpages@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>