From 39b8d397fe34ae375e33371ee58894d13667560b Mon Sep 17 00:00:00 2001

From: Cornelia Huck <cohuck@redhat.com>

Date: Tue, 15 May 2018 07:33:47 +0000

Subject: s390x/ccw: make sure all ccw devices are properly reset

Thomas reported that the subchannel for a  3270 device that ended up

in a broken state (status pending even though not enabled) did not

get out of that state even after a reboot (which involves a subsytem

reset). The reason for this is that the 3270 device did not define

a reset handler.

Let's fix this by introducing a base reset handler (set up for all

ccw devices) that resets the subchannel and have virtio-ccw call

its virtio-specific reset procedure in addition to that.

CC: qemu-stable@nongnu.org

Reported-by: Thomas Huth <thuth@redhat.com>

Suggested-by: Christian Borntraeger <borntraeger@de.ibm.com>

Reviewed-by: Thomas Huth <thuth@redhat.com>

Tested-by: Thomas Huth <thuth@redhat.com>

Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>

Reviewed-by: Halil Pasic <pasic@linux.ibm.com>

Signed-off-by: Cornelia Huck <cohuck@redhat.com>

(cherry picked from commit 838fb84f83c84f00d15b1bede5e080b495644458)

---

 hw/s390x/ccw-device.c | 8 ++++++++

 hw/s390x/virtio-ccw.c | 9 ++++++---

 hw/s390x/virtio-ccw.h | 1 +

 3 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/hw/s390x/ccw-device.c b/hw/s390x/ccw-device.c

index f9bfa15..7cd73df 100644

--- a/hw/s390x/ccw-device.c

+++ b/hw/s390x/ccw-device.c

@@ -40,6 +40,13 @@ static Property ccw_device_properties[] = {

     DEFINE_PROP_END_OF_LIST(),

 };

+static void ccw_device_reset(DeviceState *d)

+{

+    CcwDevice *ccw_dev = CCW_DEVICE(d);

+

+    css_reset_sch(ccw_dev->sch);

+}

+

 static void ccw_device_class_init(ObjectClass *klass, void *data)

 {

     DeviceClass *dc = DEVICE_CLASS(klass);

@@ -48,6 +55,7 @@ static void ccw_device_class_init(ObjectClass *klass, void *data)

     k->realize = ccw_device_realize;

     k->refill_ids = ccw_device_refill_ids;

     dc->props = ccw_device_properties;

+    dc->reset = ccw_device_reset;

 }

 const VMStateDescription vmstate_ccw_dev = {

diff --git a/hw/s390x/virtio-ccw.c b/hw/s390x/virtio-ccw.c

index 2db8cc6..dfedd84 100644

--- a/hw/s390x/virtio-ccw.c

+++ b/hw/s390x/virtio-ccw.c

@@ -1061,10 +1061,12 @@ static void virtio_ccw_reset(DeviceState *d)

 {

     VirtioCcwDevice *dev = VIRTIO_CCW_DEVICE(d);

     VirtIODevice *vdev = virtio_bus_get_device(&dev->bus);

-    CcwDevice *ccw_dev = CCW_DEVICE(d);

+    VirtIOCCWDeviceClass *vdc = VIRTIO_CCW_DEVICE_GET_CLASS(dev);

     virtio_ccw_reset_virtio(dev, vdev);

-    css_reset_sch(ccw_dev->sch);

+    if (vdc->parent_reset) {

+        vdc->parent_reset(d);

+    }

 }

 static void virtio_ccw_vmstate_change(DeviceState *d, bool running)

@@ -1721,12 +1723,13 @@ static void virtio_ccw_device_class_init(ObjectClass *klass, void *data)

 {

     DeviceClass *dc = DEVICE_CLASS(klass);

     CCWDeviceClass *k = CCW_DEVICE_CLASS(dc);

+    VirtIOCCWDeviceClass *vdc = VIRTIO_CCW_DEVICE_CLASS(klass);

     k->unplug = virtio_ccw_busdev_unplug;

     dc->realize = virtio_ccw_busdev_realize;

     dc->unrealize = virtio_ccw_busdev_unrealize;

     dc->bus_type = TYPE_VIRTUAL_CSS_BUS;

-    dc->reset = virtio_ccw_reset;

+    device_class_set_parent_reset(dc, virtio_ccw_reset, &vdc->parent_reset);

 }

 static const TypeInfo virtio_ccw_device_info = {

diff --git a/hw/s390x/virtio-ccw.h b/hw/s390x/virtio-ccw.h

index 2fc5130..3453aa1 100644

--- a/hw/s390x/virtio-ccw.h

+++ b/hw/s390x/virtio-ccw.h

@@ -77,6 +77,7 @@ typedef struct VirtIOCCWDeviceClass {

     CCWDeviceClass parent_class;

     void (*realize)(VirtioCcwDevice *dev, Error **errp);

     void (*unrealize)(VirtioCcwDevice *dev, Error **errp);

+    void (*parent_reset)(DeviceState *dev);

 } VirtIOCCWDeviceClass;

 /* Performance improves when virtqueue kick processing is decoupled from the

-- 

1.8.3.1