[Qemu-devel] [PATCH RFC 13/14] hw/block/virtio-blk: create num_queues vqs if dataplane is enabled

[Ming Lei <ming.lei@canonical.com>]

Now we only support multi vqs for dataplane case.

Signed-off-by: Ming Lei <ming.lei@canonical.com>
---
 hw/block/virtio-blk.c          |   16 +++++++++++++++-
 include/hw/virtio/virtio-blk.h |    3 +++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/hw/block/virtio-blk.c b/hw/block/virtio-blk.c
index ab99156..160b021 100644
--- a/hw/block/virtio-blk.c
+++ b/hw/block/virtio-blk.c
@@ -556,6 +556,7 @@ static void virtio_blk_update_config(VirtIODevice *vdev, uint8_t *config)
     blkcfg.physical_block_exp = get_physical_block_exp(s->conf);
     blkcfg.alignment_offset = 0;
     blkcfg.wce = bdrv_enable_write_cache(s->bs);
+    stw_p(&blkcfg.num_queues, s->blk.num_queues);
     memcpy(config, &blkcfg, sizeof(struct virtio_blk_config));
 }
 
@@ -590,6 +591,12 @@ static uint32_t virtio_blk_get_features(VirtIODevice *vdev, uint32_t features)
     if (bdrv_is_read_only(s->bs))
         features |= 1 << VIRTIO_BLK_F_RO;
 
+#ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
+    if (s->blk.num_queues > 1) {
+        features |= 1 << VIRTIO_BLK_F_MQ;
+    }
+#endif
+
     return features;
 }
 
@@ -739,8 +746,13 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
 #ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
     Error *err = NULL;
 #endif
+    int i;
     static int virtio_blk_id;
 
+#ifndef CONFIG_VIRTIO_BLK_DATA_PLANE
+    blk->num_queues = 1;
+#endif
+
     if (!blk->conf.bs) {
         error_setg(errp, "drive property not set");
         return;
@@ -765,7 +777,9 @@ static void virtio_blk_device_realize(DeviceState *dev, Error **errp)
     s->rq = NULL;
     s->sector_mask = (s->conf->logical_block_size / BDRV_SECTOR_SIZE) - 1;
 
-    s->vq = virtio_add_queue(vdev, 128, virtio_blk_handle_output);
+    for (i = 0; i < blk->num_queues; i++)
+        s->vqs[i] = virtio_add_queue(vdev, 128, virtio_blk_handle_output);
+    s->vq = s->vqs[0];
     s->complete_request = virtio_blk_complete_request;
 #ifdef CONFIG_VIRTIO_BLK_DATA_PLANE
     virtio_blk_data_plane_create(vdev, blk, &s->dataplane, &err);
diff --git a/include/hw/virtio/virtio-blk.h b/include/hw/virtio/virtio-blk.h
index ad70c9a..91489b0 100644
--- a/include/hw/virtio/virtio-blk.h
+++ b/include/hw/virtio/virtio-blk.h
@@ -50,6 +50,8 @@
 
 #define VIRTIO_BLK_ID_BYTES     20      /* ID string length */
 
+#define VIRTIO_BLK_MAX_VQS	16	/* max virtio queues supported now */
+
 struct virtio_blk_config
 {
     uint64_t capacity;
@@ -132,6 +134,7 @@ typedef struct VirtIOBlock {
     VirtIODevice parent_obj;
     BlockDriverState *bs;
     VirtQueue *vq;
+    VirtQueue *vqs[VIRTIO_BLK_MAX_VQS];
     void *rq;
     QEMUBH *bh;
     BlockConf *conf;
-- 
1.7.9.5