From 3e607cb503acbd8606e5d42e6b80adcf1ccf9a92 Mon Sep 17 00:00:00 2001
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Wed, 17 Mar 2010 13:08:05 +0200
Subject: [PATCH] virtio: add set_status callback

vhost net backend needs to be notified when
frontend status changes. Add a callback,
similar to set_features.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
---
 hw/s390-virtio-bus.c | 2 +-
 hw/syborg_virtio.c   | 2 +-
 hw/virtio-pci.c      | 5 +++--
 hw/virtio.h          | 9 +++++++++
 4 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/hw/s390-virtio-bus.c b/hw/s390-virtio-bus.c
index 9fc01e941e..3efbaabb66 100644
--- a/hw/s390-virtio-bus.c
+++ b/hw/s390-virtio-bus.c
@@ -242,7 +242,7 @@ void s390_virtio_device_update_status(VirtIOS390Device *dev)
     VirtIODevice *vdev = dev->vdev;
     uint32_t features;
 
-    vdev->status = ldub_phys(dev->dev_offs + VIRTIO_DEV_OFFS_STATUS);
+    virtio_set_status(vdev, ldub_phys(dev->dev_offs + VIRTIO_DEV_OFFS_STATUS));
 
     /* Update guest supported feature bitmap */
 
diff --git a/hw/syborg_virtio.c b/hw/syborg_virtio.c
index 65239a0572..abf0370107 100644
--- a/hw/syborg_virtio.c
+++ b/hw/syborg_virtio.c
@@ -149,7 +149,7 @@ static void syborg_virtio_writel(void *opaque, target_phys_addr_t offset,
         virtio_queue_notify(vdev, value);
         break;
     case SYBORG_VIRTIO_STATUS:
-        vdev->status = value & 0xFF;
+        virtio_set_status(vdev, value & 0xFF);
         if (vdev->status == 0)
             virtio_reset(vdev);
         break;
diff --git a/hw/virtio-pci.c b/hw/virtio-pci.c
index e23ab91992..a8b15bd464 100644
--- a/hw/virtio-pci.c
+++ b/hw/virtio-pci.c
@@ -219,7 +219,7 @@ static void virtio_ioport_write(void *opaque, uint32_t addr, uint32_t val)
         virtio_queue_notify(vdev, val);
         break;
     case VIRTIO_PCI_STATUS:
-        vdev->status = val & 0xFF;
+        virtio_set_status(vdev, val & 0xFF);
         if (vdev->status == 0) {
             virtio_reset(proxy->vdev);
             msix_unuse_all_vectors(&proxy->pci_dev);
@@ -399,7 +399,8 @@ static void virtio_write_config(PCIDevice *pci_dev, uint32_t address,
     if (PCI_COMMAND == address) {
         if (!(val & PCI_COMMAND_MASTER)) {
             if (!(proxy->bugs & VIRTIO_PCI_BUG_BUS_MASTER)) {
-                proxy->vdev->status &= ~VIRTIO_CONFIG_S_DRIVER_OK;
+                virtio_set_status(proxy->vdev,
+                                  proxy->vdev->status & ~VIRTIO_CONFIG_S_DRIVER_OK);
             }
         }
     }
diff --git a/hw/virtio.h b/hw/virtio.h
index d0155e2761..d3eb714cca 100644
--- a/hw/virtio.h
+++ b/hw/virtio.h
@@ -115,12 +115,21 @@ struct VirtIODevice
     void (*get_config)(VirtIODevice *vdev, uint8_t *config);
     void (*set_config)(VirtIODevice *vdev, const uint8_t *config);
     void (*reset)(VirtIODevice *vdev);
+    void (*set_status)(VirtIODevice *vdev, uint8_t val);
     VirtQueue *vq;
     const VirtIOBindings *binding;
     void *binding_opaque;
     uint16_t device_id;
 };
 
+static inline void virtio_set_status(VirtIODevice *vdev, uint8_t val)
+{
+    if (vdev->set_status) {
+        vdev->set_status(vdev, val);
+    }
+    vdev->status = val;
+}
+
 VirtQueue *virtio_add_queue(VirtIODevice *vdev, int queue_size,
                             void (*handle_output)(VirtIODevice *,
                                                   VirtQueue *));