[PATCH 1/4] vdpa: support packed virtqueue for set/get_vq_state()

[Jason Wang <jasowang@xxxxxxxxxx>]

This patch extends the vdpa_vq_state to support packed virtqueue
state which is basically the device/driver ring wrap counters and the
avail and used index. This will be used for the virito-vdpa support
for the packed virtqueue and the future vhost/vhost-vdpa support for
the packed virtqueue.

Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
 drivers/vdpa/ifcvf/ifcvf_main.c  |  4 ++--
 drivers/vdpa/vdpa_sim/vdpa_sim.c |  4 ++--
 drivers/vhost/vdpa.c             |  4 ++--
 include/linux/vdpa.h             | 25 +++++++++++++++++++++++--
 4 files changed, 29 insertions(+), 8 deletions(-)

diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index ab0ab5cf0f6e..5d3891b1ca28 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -264,7 +264,7 @@ static int ifcvf_vdpa_get_vq_state(struct vdpa_device *vdpa_dev, u16 qid,
 {
 	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
 
-	state->avail_index = ifcvf_get_vq_state(vf, qid);
+	state->split.avail_index = ifcvf_get_vq_state(vf, qid);
 	return 0;
 }
 
@@ -273,7 +273,7 @@ static int ifcvf_vdpa_set_vq_state(struct vdpa_device *vdpa_dev, u16 qid,
 {
 	struct ifcvf_hw *vf = vdpa_to_vf(vdpa_dev);
 
-	return ifcvf_set_vq_state(vf, qid, state->avail_index);
+	return ifcvf_set_vq_state(vf, qid, state->split.avail_index);
 }
 
 static void ifcvf_vdpa_set_vq_cb(struct vdpa_device *vdpa_dev, u16 qid,
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 98f793bc9376..14e024de5cbf 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -374,7 +374,7 @@ static int vdpasim_set_vq_state(struct vdpa_device *vdpa, u16 idx,
 	struct vringh *vrh = &vq->vring;
 
 	spin_lock(&vdpasim->lock);
-	vrh->last_avail_idx = state->avail_index;
+	vrh->last_avail_idx = state->split.avail_index;
 	spin_unlock(&vdpasim->lock);
 
 	return 0;
@@ -387,7 +387,7 @@ static int vdpasim_get_vq_state(struct vdpa_device *vdpa, u16 idx,
 	struct vdpasim_virtqueue *vq = &vdpasim->vqs[idx];
 	struct vringh *vrh = &vq->vring;
 
-	state->avail_index = vrh->last_avail_idx;
+	state->split.avail_index = vrh->last_avail_idx;
 	return 0;
 }
 
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index fb41db3da611..210ab35a7ebf 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -383,7 +383,7 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 		if (r)
 			return r;
 
-		vq->last_avail_idx = vq_state.avail_index;
+		vq->last_avail_idx = vq_state.split.avail_index;
 		break;
 	}
 
@@ -401,7 +401,7 @@ static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
 		break;
 
 	case VHOST_SET_VRING_BASE:
-		vq_state.avail_index = vq->last_avail_idx;
+		vq_state.split.avail_index = vq->last_avail_idx;
 		if (ops->set_vq_state(vdpa, idx, &vq_state))
 			r = -EINVAL;
 		break;
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index f311d227aa1b..3357ac98878d 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -28,13 +28,34 @@ struct vdpa_notification_area {
 };
 
 /**
- * struct vdpa_vq_state - vDPA vq_state definition
+ * struct vdpa_vq_state_split - vDPA split virtqueue state
  * @avail_index: available index
  */
-struct vdpa_vq_state {
+struct vdpa_vq_state_split {
 	u16	avail_index;
 };
 
+/**
+ * struct vdpa_vq_state_packed - vDPA packed virtqueue state
+ * @last_avail_counter: last driver ring wrap counter observed by device
+ * @last_avail_idx: device available index
+ * @last_used_counter: device ring wrap counter
+ * @last_used_idx: used index
+ */
+struct vdpa_vq_state_packed {
+        u16	last_avail_counter:1;
+        u16	last_avail_idx:15;
+        u16	last_used_counter:1;
+        u16	last_used_idx:15;
+};
+
+struct vdpa_vq_state {
+     union {
+          struct vdpa_vq_state_split split;
+          struct vdpa_vq_state_packed packed;
+     };
+};
+
 struct vdpa_mgmt_dev;
 
 /**
-- 
2.25.1