hw/virtio: move vm_running check to virtio_device_started

All the boilerplate virtio code does the same thing (or should at
least) of checking to see if the VM is running before attempting to
start VirtIO. Push the logic up to the common function to avoid
getting a copy and paste wrong.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-11-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/virtio/vhost-user-fs.c

@@ -122,11 +122,7 @@ static void vuf_stop(VirtIODevice *vdev)
 static void vuf_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostUserFS *fs = VHOST_USER_FS(vdev);
-    bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
-
-    if (!vdev->vm_running) {
-        should_start = false;
-    }
+    bool should_start = virtio_device_started(vdev, status);
 
     if (fs->vhost_dev.started == should_start) {
         return;

hw/virtio/vhost-user-i2c.c

@@ -93,11 +93,7 @@ static void vu_i2c_stop(VirtIODevice *vdev)
 static void vu_i2c_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
-    bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
-
-    if (!vdev->vm_running) {
-        should_start = false;
-    }
+    bool should_start = virtio_device_started(vdev, status);
 
     if (i2c->vhost_dev.started == should_start) {
         return;

hw/virtio/vhost-user-rng.c

@@ -90,11 +90,7 @@ static void vu_rng_stop(VirtIODevice *vdev)
 static void vu_rng_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostUserRNG *rng = VHOST_USER_RNG(vdev);
-    bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
-
-    if (!vdev->vm_running) {
-        should_start = false;
-    }
+    bool should_start = virtio_device_started(vdev, status);
 
     if (rng->vhost_dev.started == should_start) {
         return;

hw/virtio/vhost-user-vsock.c

@@ -55,11 +55,7 @@ const VhostDevConfigOps vsock_ops = {
 static void vuv_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
-    bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
-
-    if (!vdev->vm_running) {
-        should_start = false;
-    }
+    bool should_start = virtio_device_started(vdev, status);
 
     if (vvc->vhost_dev.started == should_start) {
         return;

hw/virtio/vhost-vsock.c

@@ -70,13 +70,9 @@ static int vhost_vsock_set_running(VirtIODevice *vdev, int start)
 static void vhost_vsock_set_status(VirtIODevice *vdev, uint8_t status)
 {
     VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
-    bool should_start = status & VIRTIO_CONFIG_S_DRIVER_OK;
+    bool should_start = virtio_device_started(vdev, status);
     int ret;
 
-    if (!vdev->vm_running) {
-        should_start = false;
-    }
-
     if (vvc->vhost_dev.started == should_start) {
         return;
     }

include/hw/virtio/virtio.h

@@ -100,6 +100,7 @@ struct VirtIODevice
     VirtQueue *vq;
     MemoryListener listener;
     uint16_t device_id;
+    /* @vm_running: current VM running state via virtio_vmstate_change() */
     bool vm_running;
     bool broken; /* device in invalid state, needs reset */
     bool use_disabled_flag; /* allow use of 'disable' flag when needed */
@@ -376,6 +377,10 @@ static inline bool virtio_device_started(VirtIODevice *vdev, uint8_t status)
         return vdev->started;
     }
 
+    if (!vdev->vm_running) {
+        return false;
+    }
+
     return status & VIRTIO_CONFIG_S_DRIVER_OK;
 }