vdpa/mlx5: Decouple cvq iotlb handling from hw mapping code

The handling of the cvq iotlb is currently coupled with the creation
and destruction of the hardware mkeys (mr).

This patch moves cvq iotlb handling into its own function and shifts it
to a scope that is not related to mr handling. As cvq handling is just a
prune_iotlb + dup_iotlb cycle, put it all in the same "update" function.
Finally, the destruction path is handled by directly pruning the iotlb.

After this move is done the ASID mr code can be collapsed into a single
function.
Acked-by: Jason Wang <jasowang@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Message-Id: <20231018171456.1624030-8-dtatulea@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Si-Wei Liu <si-wei.liu@oracle.com>
Tested-by: Lei Yang <leiyang@redhat.com>

drivers/vdpa/mlx5/core/mlx5_vdpa.h

@@ -120,6 +120,9 @@ int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
 			unsigned int asid);
 void mlx5_vdpa_destroy_mr(struct mlx5_vdpa_dev *mvdev);
 void mlx5_vdpa_destroy_mr_asid(struct mlx5_vdpa_dev *mvdev, unsigned int asid);
+int mlx5_vdpa_update_cvq_iotlb(struct mlx5_vdpa_dev *mvdev,
+				struct vhost_iotlb *iotlb,
+				unsigned int asid);
 int mlx5_vdpa_create_dma_mr(struct mlx5_vdpa_dev *mvdev);
 
 #define mlx5_vdpa_warn(__dev, format, ...)                                                         \

drivers/vdpa/mlx5/core/mr.c

@@ -489,14 +489,6 @@ static void destroy_user_mr(struct mlx5_vdpa_dev *mvdev, struct mlx5_vdpa_mr *mr
 	}
 }
 
-static void _mlx5_vdpa_destroy_cvq_mr(struct mlx5_vdpa_dev *mvdev, unsigned int asid)
-{
-	if (mvdev->group2asid[MLX5_VDPA_CVQ_GROUP] != asid)
-		return;
-
-	prune_iotlb(mvdev);
-}
-
 static void _mlx5_vdpa_destroy_dvq_mr(struct mlx5_vdpa_dev *mvdev, unsigned int asid)
 {
 	struct mlx5_vdpa_mr *mr = &mvdev->mr;
@@ -522,25 +514,14 @@ void mlx5_vdpa_destroy_mr_asid(struct mlx5_vdpa_dev *mvdev, unsigned int asid)
 	mutex_lock(&mr->mkey_mtx);
 
 	_mlx5_vdpa_destroy_dvq_mr(mvdev, asid);
-	_mlx5_vdpa_destroy_cvq_mr(mvdev, asid);
 
 	mutex_unlock(&mr->mkey_mtx);
 }
 
 void mlx5_vdpa_destroy_mr(struct mlx5_vdpa_dev *mvdev)
 {
-	mlx5_vdpa_destroy_mr_asid(mvdev, mvdev->group2asid[MLX5_VDPA_CVQ_GROUP]);
 	mlx5_vdpa_destroy_mr_asid(mvdev, mvdev->group2asid[MLX5_VDPA_DATAVQ_GROUP]);
-}
-
-static int _mlx5_vdpa_create_cvq_mr(struct mlx5_vdpa_dev *mvdev,
-				    struct vhost_iotlb *iotlb,
-				    unsigned int asid)
-{
-	if (mvdev->group2asid[MLX5_VDPA_CVQ_GROUP] != asid)
-		return 0;
-
-	return dup_iotlb(mvdev, iotlb);
+	prune_iotlb(mvdev);
 }
 
 static int _mlx5_vdpa_create_dvq_mr(struct mlx5_vdpa_dev *mvdev,
@@ -572,22 +553,7 @@ static int _mlx5_vdpa_create_dvq_mr(struct mlx5_vdpa_dev *mvdev,
 static int _mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev,
 				struct vhost_iotlb *iotlb, unsigned int asid)
 {
-	int err;
-
-	err = _mlx5_vdpa_create_dvq_mr(mvdev, iotlb, asid);
-	if (err)
-		return err;
-
-	err = _mlx5_vdpa_create_cvq_mr(mvdev, iotlb, asid);
-	if (err)
-		goto out_err;
-
-	return 0;
-
-out_err:
-	_mlx5_vdpa_destroy_dvq_mr(mvdev, asid);
-
-	return err;
+	return _mlx5_vdpa_create_dvq_mr(mvdev, iotlb, asid);
 }
 
 int mlx5_vdpa_create_mr(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
@@ -620,7 +586,24 @@ int mlx5_vdpa_handle_set_map(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *io
 	return err;
 }
 
+int mlx5_vdpa_update_cvq_iotlb(struct mlx5_vdpa_dev *mvdev,
+				struct vhost_iotlb *iotlb,
+				unsigned int asid)
+{
+	if (mvdev->group2asid[MLX5_VDPA_CVQ_GROUP] != asid)
+		return 0;
+
+	prune_iotlb(mvdev);
+	return dup_iotlb(mvdev, iotlb);
+}
+
 int mlx5_vdpa_create_dma_mr(struct mlx5_vdpa_dev *mvdev)
 {
-	return mlx5_vdpa_create_mr(mvdev, NULL, 0);
+	int err;
+
+	err = mlx5_vdpa_create_mr(mvdev, NULL, 0);
+	if (err)
+		return err;
+
+	return mlx5_vdpa_update_cvq_iotlb(mvdev, NULL, 0);
 }

drivers/vdpa/mlx5/net/mlx5_vnet.c

@@ -2928,10 +2928,13 @@ static int set_map_data(struct mlx5_vdpa_dev *mvdev, struct vhost_iotlb *iotlb,
 		return err;
 	}
 
-	if (change_map)
+	if (change_map) {
 		err = mlx5_vdpa_change_map(mvdev, iotlb, asid);
+		if (err)
+			return err;
+	}
 
-	return err;
+	return mlx5_vdpa_update_cvq_iotlb(mvdev, iotlb, asid);
 }
 
 static int mlx5_vdpa_set_map(struct vdpa_device *vdev, unsigned int asid,