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-rw-r--r--hw/block/dataplane/virtio-blk.c20
1 files changed, 19 insertions, 1 deletions
diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index e88862d..d6ba65c 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -34,6 +34,7 @@ struct VirtIOBlockDataPlane {
VirtIODevice *vdev;
Vring vring; /* virtqueue vring */
EventNotifier *guest_notifier; /* irq */
+ QEMUBH *bh; /* bh for guest notification */
/* Note that these EventNotifiers are assigned by value. This is
* fine as long as you do not call event_notifier_cleanup on them
@@ -61,13 +62,28 @@ static void notify_guest(VirtIOBlockDataPlane *s)
event_notifier_set(s->guest_notifier);
}
+static void notify_guest_bh(void *opaque)
+{
+ VirtIOBlockDataPlane *s = opaque;
+
+ notify_guest(s);
+}
+
static void complete_request_vring(VirtIOBlockReq *req, unsigned char status)
{
+ VirtIOBlockDataPlane *s = req->dev->dataplane;
stb_p(&req->in->status, status);
vring_push(&req->dev->dataplane->vring, &req->elem,
req->qiov.size + sizeof(*req->in));
- notify_guest(req->dev->dataplane);
+
+ /* Suppress notification to guest by BH and its scheduled
+ * flag because requests are completed as a batch after io
+ * plug & unplug is introduced, and the BH can still be
+ * executed in dataplane aio context even after it is
+ * stopped, so needn't worry about notification loss with BH.
+ */
+ qemu_bh_schedule(s->bh);
}
static void handle_notify(EventNotifier *e)
@@ -172,6 +188,7 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *blk,
s->iothread = &s->internal_iothread_obj;
}
s->ctx = iothread_get_aio_context(s->iothread);
+ s->bh = aio_bh_new(s->ctx, notify_guest_bh, s);
error_setg(&s->blocker, "block device is in use by data plane");
bdrv_op_block_all(blk->conf.bs, s->blocker);
@@ -190,6 +207,7 @@ void virtio_blk_data_plane_destroy(VirtIOBlockDataPlane *s)
bdrv_op_unblock_all(s->blk->conf.bs, s->blocker);
error_free(s->blocker);
object_unref(OBJECT(s->iothread));
+ qemu_bh_delete(s->bh);
g_free(s);
}
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