virtio_ring: split vring_virtqueue

Separate the two inline structures(split and packed) from the structure
vring_virtqueue.

In this way, we can use these two structures later to pass parameters
and retain temporary variables.
Signed-off-by: Xuan Zhuo <xuanzhuo@linux.alibaba.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Message-Id: <20220801063902.129329-6-xuanzhuo@linux.alibaba.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

drivers/virtio/virtio_ring.c

@@ -85,6 +85,64 @@ struct vring_desc_extra {
 	u16 next;			/* The next desc state in a list. */
 };
 
+struct vring_virtqueue_split {
+	/* Actual memory layout for this queue. */
+	struct vring vring;
+
+	/* Last written value to avail->flags */
+	u16 avail_flags_shadow;
+
+	/*
+	 * Last written value to avail->idx in
+	 * guest byte order.
+	 */
+	u16 avail_idx_shadow;
+
+	/* Per-descriptor state. */
+	struct vring_desc_state_split *desc_state;
+	struct vring_desc_extra *desc_extra;
+
+	/* DMA address and size information */
+	dma_addr_t queue_dma_addr;
+	size_t queue_size_in_bytes;
+};
+
+struct vring_virtqueue_packed {
+	/* Actual memory layout for this queue. */
+	struct {
+		unsigned int num;
+		struct vring_packed_desc *desc;
+		struct vring_packed_desc_event *driver;
+		struct vring_packed_desc_event *device;
+	} vring;
+
+	/* Driver ring wrap counter. */
+	bool avail_wrap_counter;
+
+	/* Avail used flags. */
+	u16 avail_used_flags;
+
+	/* Index of the next avail descriptor. */
+	u16 next_avail_idx;
+
+	/*
+	 * Last written value to driver->flags in
+	 * guest byte order.
+	 */
+	u16 event_flags_shadow;
+
+	/* Per-descriptor state. */
+	struct vring_desc_state_packed *desc_state;
+	struct vring_desc_extra *desc_extra;
+
+	/* DMA address and size information */
+	dma_addr_t ring_dma_addr;
+	dma_addr_t driver_event_dma_addr;
+	dma_addr_t device_event_dma_addr;
+	size_t ring_size_in_bytes;
+	size_t event_size_in_bytes;
+};
+
 struct vring_virtqueue {
 	struct virtqueue vq;
 
@@ -124,64 +182,10 @@ struct vring_virtqueue {
 
 	union {
 		/* Available for split ring */
-		struct {
-			/* Actual memory layout for this queue. */
-			struct vring vring;
-
-			/* Last written value to avail->flags */
-			u16 avail_flags_shadow;
-
-			/*
-			 * Last written value to avail->idx in
-			 * guest byte order.
-			 */
-			u16 avail_idx_shadow;
-
-			/* Per-descriptor state. */
-			struct vring_desc_state_split *desc_state;
-			struct vring_desc_extra *desc_extra;
-
-			/* DMA address and size information */
-			dma_addr_t queue_dma_addr;
-			size_t queue_size_in_bytes;
-		} split;
+		struct vring_virtqueue_split split;
 
 		/* Available for packed ring */
-		struct {
-			/* Actual memory layout for this queue. */
-			struct {
-				unsigned int num;
-				struct vring_packed_desc *desc;
-				struct vring_packed_desc_event *driver;
-				struct vring_packed_desc_event *device;
-			} vring;
-
-			/* Driver ring wrap counter. */
-			bool avail_wrap_counter;
-
-			/* Avail used flags. */
-			u16 avail_used_flags;
-
-			/* Index of the next avail descriptor. */
-			u16 next_avail_idx;
-
-			/*
-			 * Last written value to driver->flags in
-			 * guest byte order.
-			 */
-			u16 event_flags_shadow;
-
-			/* Per-descriptor state. */
-			struct vring_desc_state_packed *desc_state;
-			struct vring_desc_extra *desc_extra;
-
-			/* DMA address and size information */
-			dma_addr_t ring_dma_addr;
-			dma_addr_t driver_event_dma_addr;
-			dma_addr_t device_event_dma_addr;
-			size_t ring_size_in_bytes;
-			size_t event_size_in_bytes;
-		} packed;
+		struct vring_virtqueue_packed packed;
 	};
 
 	/* How to notify other side. FIXME: commonalize hcalls! */