virtio-blk: add iothread-vq-mapping parameter

Add the iothread-vq-mapping parameter to assign virtqueues to IOThreads.
Store the vq:AioContext mapping in the new struct
VirtIOBlockDataPlane->vq_aio_context[] field and refactor the code to
use the per-vq AioContext instead of the BlockDriverState's AioContext.

Reimplement --device virtio-blk-pci,iothread= and non-IOThread mode by
assigning all virtqueues to the IOThread and main loop's AioContext in
vq_aio_context[], respectively.

The comment in struct VirtIOBlockDataPlane about EventNotifiers is
stale. Remove it.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-ID: <20231220134755.814917-5-stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h
index 9881009c22..5e4091e4da 100644
--- a/include/hw/virtio/virtio-blk.h
+++ b/include/hw/virtio/virtio-blk.h
@@ -21,6 +21,7 @@
 #include "sysemu/block-backend.h"
 #include "sysemu/block-ram-registrar.h"
 #include "qom/object.h"
+#include "qapi/qapi-types-virtio.h"
 
 #define TYPE_VIRTIO_BLK "virtio-blk-device"
 OBJECT_DECLARE_SIMPLE_TYPE(VirtIOBlock, VIRTIO_BLK)
@@ -37,6 +38,7 @@ struct VirtIOBlkConf
 {
     BlockConf conf;
     IOThread *iothread;
+    IOThreadVirtQueueMappingList *iothread_vq_mapping_list;
     char *serial;
     uint32_t request_merging;
     uint16_t num_queues;