Commit cae15c2e authored by Eli Cohen's avatar Eli Cohen Committed by Michael S. Tsirkin
Browse files

vdpa/mlx5: Implement susupend virtqueue callback 



Implement the suspend callback allowing to suspend the virtqueues so
they stop processing descriptors. This is required to allow to query a
consistent state of the virtqueue while live migration is taking place.

Signed-off-by: default avatarEli Cohen <elic@nvidia.com>
Message-Id: <20220714113927.85729-2-elic@nvidia.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent ad146355

drivers/vdpa/mlx5/net/mlx5_vnet.c

+80 −3
Original line number Diff line number Diff line
@@ -164,6 +164,7 @@ struct mlx5_vdpa_net { 
	bool setup;

	u32 cur_num_vqs;

	u32 rqt_size;

	bool nb_registered;

	struct notifier_block nb;

	struct vdpa_callback config_cb;

	struct mlx5_vdpa_wq_ent cvq_ent;
@@ -895,6 +896,7 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque 
	if (err)

		goto err_cmd;



	mvq->fw_state = MLX5_VIRTIO_NET_Q_OBJECT_STATE_INIT;

	kfree(in);

	mvq->virtq_id = MLX5_GET(general_obj_out_cmd_hdr, out, obj_id);
@@ -922,6 +924,7 @@ static void destroy_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtq 
		mlx5_vdpa_warn(&ndev->mvdev, "destroy virtqueue 0x%x\n", mvq->virtq_id);

		return;

	}

	mvq->fw_state = MLX5_VIRTIO_NET_Q_OBJECT_NONE;

	umems_destroy(ndev, mvq);

}
@@ -1121,6 +1124,20 @@ static int query_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueu 
	return err;

}



static bool is_valid_state_change(int oldstate, int newstate)

{

	switch (oldstate) {

	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_INIT:

		return newstate == MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY;

	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY:

		return newstate == MLX5_VIRTIO_NET_Q_OBJECT_STATE_SUSPEND;

	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_SUSPEND:

	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_ERR:

	default:

		return false;

	}

}



static int modify_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq, int state)

{

	int inlen = MLX5_ST_SZ_BYTES(modify_virtio_net_q_in);
@@ -1130,6 +1147,12 @@ static int modify_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque 
	void *in;

	int err;



	if (mvq->fw_state == MLX5_VIRTIO_NET_Q_OBJECT_NONE)

		return 0;



	if (!is_valid_state_change(mvq->fw_state, state))

		return -EINVAL;



	in = kzalloc(inlen, GFP_KERNEL);

	if (!in)

		return -ENOMEM;
@@ -1992,6 +2015,7 @@ static void mlx5_vdpa_set_vq_ready(struct vdpa_device *vdev, u16 idx, bool ready 
	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);

	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);

	struct mlx5_vdpa_virtqueue *mvq;

	int err;



	if (!mvdev->actual_features)

		return;
@@ -2005,8 +2029,16 @@ static void mlx5_vdpa_set_vq_ready(struct vdpa_device *vdev, u16 idx, bool ready 
	}



	mvq = &ndev->vqs[idx];

	if (!ready)

	if (!ready) {

		suspend_vq(ndev, mvq);

	} else {

		err = modify_virtqueue(ndev, mvq, MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY);

		if (err) {

			mlx5_vdpa_warn(mvdev, "modify VQ %d to ready failed (%d)\n", idx, err);

			ready = false;

		}

	}





	mvq->ready = ready;

}
@@ -2733,6 +2765,37 @@ static int mlx5_vdpa_get_vendor_vq_stats(struct vdpa_device *vdev, u16 idx, 
	return err;

}



static void mlx5_vdpa_cvq_suspend(struct mlx5_vdpa_dev *mvdev)

{

	struct mlx5_control_vq *cvq;



	if (!(mvdev->actual_features & BIT_ULL(VIRTIO_NET_F_CTRL_VQ)))

		return;



	cvq = &mvdev->cvq;

	cvq->ready = false;

}



static int mlx5_vdpa_suspend(struct vdpa_device *vdev)

{

	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);

	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);

	struct mlx5_vdpa_virtqueue *mvq;

	int i;



	down_write(&ndev->reslock);

	mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);

	ndev->nb_registered = false;

	flush_workqueue(ndev->mvdev.wq);

	for (i = 0; i < ndev->cur_num_vqs; i++) {

		mvq = &ndev->vqs[i];

		suspend_vq(ndev, mvq);

	}

	mlx5_vdpa_cvq_suspend(mvdev);

	up_write(&ndev->reslock);

	return 0;

}



static const struct vdpa_config_ops mlx5_vdpa_ops = {

	.set_vq_address = mlx5_vdpa_set_vq_address,

	.set_vq_num = mlx5_vdpa_set_vq_num,
@@ -2763,6 +2826,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = { 
	.get_generation = mlx5_vdpa_get_generation,

	.set_map = mlx5_vdpa_set_map,

	.free = mlx5_vdpa_free,

	.suspend = mlx5_vdpa_suspend,

};



static int query_mtu(struct mlx5_core_dev *mdev, u16 *mtu)
@@ -2828,6 +2892,7 @@ static void init_mvqs(struct mlx5_vdpa_net *ndev) 
		mvq->index = i;

		mvq->ndev = ndev;

		mvq->fwqp.fw = true;

		mvq->fw_state = MLX5_VIRTIO_NET_Q_OBJECT_NONE;

	}

	for (; i < ndev->mvdev.max_vqs; i++) {

		mvq = &ndev->vqs[i];
@@ -2902,13 +2967,21 @@ static int event_handler(struct notifier_block *nb, unsigned long event, void *p 
		switch (eqe->sub_type) {

		case MLX5_PORT_CHANGE_SUBTYPE_DOWN:

		case MLX5_PORT_CHANGE_SUBTYPE_ACTIVE:

			down_read(&ndev->reslock);

			if (!ndev->nb_registered) {

				up_read(&ndev->reslock);

				return NOTIFY_DONE;

			}

			wqent = kzalloc(sizeof(*wqent), GFP_ATOMIC);

			if (!wqent)

			if (!wqent) {

				up_read(&ndev->reslock);

				return NOTIFY_DONE;

			}



			wqent->mvdev = &ndev->mvdev;

			INIT_WORK(&wqent->work, update_carrier);

			queue_work(ndev->mvdev.wq, &wqent->work);

			up_read(&ndev->reslock);

			ret = NOTIFY_OK;

			break;

		default:
@@ -3062,6 +3135,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name, 


	ndev->nb.notifier_call = event_handler;

	mlx5_notifier_register(mdev, &ndev->nb);

	ndev->nb_registered = true;

	mvdev->vdev.mdev = &mgtdev->mgtdev;

	err = _vdpa_register_device(&mvdev->vdev, max_vqs + 1);

	if (err)
@@ -3093,7 +3167,10 @@ static void mlx5_vdpa_dev_del(struct vdpa_mgmt_dev *v_mdev, struct vdpa_device * 
	struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);

	struct workqueue_struct *wq;



	if (ndev->nb_registered) {

		mlx5_notifier_unregister(mvdev->mdev, &ndev->nb);

		ndev->nb_registered = false;

	}

	wq = mvdev->wq;

	mvdev->wq = NULL;

	destroy_workqueue(wq);

include/linux/mlx5/mlx5_ifc_vdpa.h

+8 −0
Original line number Diff line number Diff line
@@ -150,6 +150,14 @@ enum { 
	MLX5_VIRTIO_NET_Q_OBJECT_STATE_ERR      = 0x3,

};



/* This indicates that the object was not created or has already

 * been desroyed. It is very safe to assume that this object will never

 * have so many states

 */

enum {

	MLX5_VIRTIO_NET_Q_OBJECT_NONE = 0xffffffff

};



enum {

	MLX5_RQTC_LIST_Q_TYPE_RQ            = 0x0,

	MLX5_RQTC_LIST_Q_TYPE_VIRTIO_NET_Q  = 0x1,