[Qemu-devel] [PATCH] virtio-blk: Drop x-data-plane option

[Fam Zheng <famz@redhat.com>]

The official way of enabling dataplane is through the "iothread"
property that references an iothread object created by "-object
iothread".  Since the old "x-data-plane=on" way now even crashes, it's
probably easier to just drop it:

$ qemu-system-x86_64 -drive file=null-co://,id=d0,if=none \
    -device virtio-blk-pci,drive=d0,x-data-plane=on

ERROR:/home/fam/work/qemu/qom/object.c:1515:
object_get_canonical_path_component: assertion failed: (obj->parent != NULL)
Aborted

Signed-off-by: Fam Zheng <famz@redhat.com>
---
 hw/block/dataplane/virtio-blk.c | 15 ++-------------
 hw/block/virtio-blk.c           |  1 -
 include/hw/virtio/virtio-blk.h  |  1 -
 3 files changed, 2 insertions(+), 15 deletions(-)

diff --git a/hw/block/dataplane/virtio-blk.c b/hw/block/dataplane/virtio-blk.c
index c42ddeb..c57f293 100644
--- a/hw/block/dataplane/virtio-blk.c
+++ b/hw/block/dataplane/virtio-blk.c
@@ -45,7 +45,6 @@ struct VirtIOBlockDataPlane {
      * use it).
      */
     IOThread *iothread;
-    IOThread internal_iothread_obj;
     AioContext *ctx;
     EventNotifier host_notifier;    /* doorbell */
 
@@ -149,14 +148,14 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf,
 
     *dataplane = NULL;
 
-    if (!conf->data_plane && !conf->iothread) {
+    if (!conf->iothread) {
         return;
     }
 
     /* Don't try if transport does not support notifiers. */
     if (!k->set_guest_notifiers || !k->set_host_notifier) {
         error_setg(errp,
-                   "device is incompatible with x-data-plane "
+                   "device is incompatible with dataplane "
                    "(transport does not support notifiers)");
         return;
     }
@@ -179,16 +178,6 @@ void virtio_blk_data_plane_create(VirtIODevice *vdev, VirtIOBlkConf *conf,
     if (conf->iothread) {
         s->iothread = conf->iothread;
         object_ref(OBJECT(s->iothread));
-    } else {
-        /* Create per-device IOThread if none specified.  This is for
-         * x-data-plane option compatibility.  If x-data-plane is removed we
-         * can drop this.
-         */
-        object_initialize(&s->internal_iothread_obj,
-                          sizeof(s->internal_iothread_obj),
-                          TYPE_IOTHREAD);
-        user_creatable_complete(OBJECT(&s->internal_iothread_obj), &error_abort);
-        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);
diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index 756ae5c..b88b726 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -986,7 +986,6 @@ static Property virtio_blk_properties[] = {
 #endif
     DEFINE_PROP_BIT("request-merging", VirtIOBlock, conf.request_merging, 0,
                     true),
-    DEFINE_PROP_BIT("x-data-plane", VirtIOBlock, conf.data_plane, 0, false),
     DEFINE_PROP_END_OF_LIST(),
 };
 
diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h
index 6bf5905..ae11a63 100644
--- a/include/hw/virtio/virtio-blk.h
+++ b/include/hw/virtio/virtio-blk.h
@@ -37,7 +37,6 @@ struct VirtIOBlkConf
     char *serial;
     uint32_t scsi;
     uint32_t config_wce;
-    uint32_t data_plane;
     uint32_t request_merging;
 };
 
-- 
2.4.3