hw/virtio: move vhd->started check into helper and add FIXME

The `started` field is manipulated internally within the vhost code
except for one place, vhost-user-blk via f5b22d06fb (vhost: recheck
dev state in the vhost_migration_log routine). Mark that as a FIXME
because it introduces a potential race. I think the referenced fix
should be tracking its state locally.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20220802095010.3330793-12-alex.bennee@linaro.org>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Raphael Norwitz <raphael.norwittz@nutanix.com>

6 files changed, 10 insertions, 8 deletions

diff --git a/hw/virtio/vhost-user-fs.c b/hw/virtio/vhost-user-fs.c
index d2bebba785..ad0f91c607 100644
--- a/hw/virtio/vhost-user-fs.c
+++ b/hw/virtio/vhost-user-fs.c
@@ -20,6 +20,7 @@
 #include "hw/virtio/virtio-bus.h"
 #include "hw/virtio/virtio-access.h"
 #include "qemu/error-report.h"
+#include "hw/virtio/vhost.h"
 #include "hw/virtio/vhost-user-fs.h"
 #include "monitor/monitor.h"
 #include "sysemu/sysemu.h"
@@ -124,7 +125,7 @@ static void vuf_set_status(VirtIODevice *vdev, uint8_t status)
     VHostUserFS *fs = VHOST_USER_FS(vdev);
     bool should_start = virtio_device_started(vdev, status);
 
-    if (fs->vhost_dev.started == should_start) {
+    if (vhost_dev_is_started(&fs->vhost_dev) == should_start) {
         return;
     }
 
diff --git a/hw/virtio/vhost-user-i2c.c b/hw/virtio/vhost-user-i2c.c
index b930cf6d5e..bc58b6c0d1 100644
--- a/hw/virtio/vhost-user-i2c.c
+++ b/hw/virtio/vhost-user-i2c.c
@@ -95,7 +95,7 @@ static void vu_i2c_set_status(VirtIODevice *vdev, uint8_t status)
     VHostUserI2C *i2c = VHOST_USER_I2C(vdev);
     bool should_start = virtio_device_started(vdev, status);
 
-    if (i2c->vhost_dev.started == should_start) {
+    if (vhost_dev_is_started(&i2c->vhost_dev) == should_start) {
         return;
     }
 
@@ -174,7 +174,7 @@ static void vu_i2c_disconnect(DeviceState *dev)
     }
     i2c->connected = false;
 
-    if (i2c->vhost_dev.started) {
+    if (vhost_dev_is_started(&i2c->vhost_dev)) {
         vu_i2c_stop(vdev);
     }
 }
diff --git a/hw/virtio/vhost-user-rng.c b/hw/virtio/vhost-user-rng.c
index a9c1c4bc79..bc1f36c5ac 100644
--- a/hw/virtio/vhost-user-rng.c
+++ b/hw/virtio/vhost-user-rng.c
@@ -92,7 +92,7 @@ static void vu_rng_set_status(VirtIODevice *vdev, uint8_t status)
     VHostUserRNG *rng = VHOST_USER_RNG(vdev);
     bool should_start = virtio_device_started(vdev, status);
 
-    if (rng->vhost_dev.started == should_start) {
+    if (vhost_dev_is_started(&rng->vhost_dev) == should_start) {
         return;
     }
 
@@ -160,7 +160,7 @@ static void vu_rng_disconnect(DeviceState *dev)
 
     rng->connected = false;
 
-    if (rng->vhost_dev.started) {
+    if (vhost_dev_is_started(&rng->vhost_dev)) {
         vu_rng_stop(vdev);
     }
 }
diff --git a/hw/virtio/vhost-user-vsock.c b/hw/virtio/vhost-user-vsock.c
index 22c1616ebd..7b67e29d83 100644
--- a/hw/virtio/vhost-user-vsock.c
+++ b/hw/virtio/vhost-user-vsock.c
@@ -57,7 +57,7 @@ static void vuv_set_status(VirtIODevice *vdev, uint8_t status)
     VHostVSockCommon *vvc = VHOST_VSOCK_COMMON(vdev);
     bool should_start = virtio_device_started(vdev, status);
 
-    if (vvc->vhost_dev.started == should_start) {
+    if (vhost_dev_is_started(&vvc->vhost_dev) == should_start) {
         return;
     }
 
diff --git a/hw/virtio/vhost-vsock-common.c b/hw/virtio/vhost-vsock-common.c
index 7394818e00..29b9ab4f72 100644
--- a/hw/virtio/vhost-vsock-common.c
+++ b/hw/virtio/vhost-vsock-common.c
@@ -14,6 +14,7 @@
 #include "hw/virtio/virtio-access.h"
 #include "qemu/error-report.h"
 #include "hw/qdev-properties.h"
+#include "hw/virtio/vhost.h"
 #include "hw/virtio/vhost-vsock.h"
 #include "qemu/iov.h"
 #include "monitor/monitor.h"
@@ -199,7 +200,7 @@ int vhost_vsock_common_pre_save(void *opaque)
      * At this point, backend must be stopped, otherwise
      * it might keep writing to memory.
      */
-    assert(!vvc->vhost_dev.started);
+    assert(!vhost_dev_is_started(&vvc->vhost_dev));
 
     return 0;
 }
diff --git a/hw/virtio/vhost-vsock.c b/hw/virtio/vhost-vsock.c
index 8031c164a5..7dc3c73931 100644
--- a/hw/virtio/vhost-vsock.c
+++ b/hw/virtio/vhost-vsock.c
@@ -73,7 +73,7 @@ static void vhost_vsock_set_status(VirtIODevice *vdev, uint8_t status)
     bool should_start = virtio_device_started(vdev, status);
     int ret;
 
-    if (vvc->vhost_dev.started == should_start) {
+    if (vhost_dev_is_started(&vvc->vhost_dev) == should_start) {
         return;
     }