Commit c384c240 authored by Eli Cohen's avatar Eli Cohen Committed by Michael S. Tsirkin
Browse files

vdpa/mlx5: Avoid losing link state updates 



Current code ignores link state updates if VIRTIO_NET_F_STATUS was not
negotiated. However, link state updates could be received before feature
negotiation was completed , therefore causing link state events to be
lost, possibly leaving the link state down.

Modify the code so link state notifier is registered after DRIVER_OK was
negotiated and carry the registration only if
VIRTIO_NET_F_STATUS was negotiated.  Unregister the notifier when the
device is reset.

Fixes: 033779a7 ("vdpa/mlx5: make MTU/STATUS presence conditional on feature bits")
Acked-by: default avatarJason Wang <jasowang@redhat.com>
Signed-off-by: default avatarEli Cohen <elic@nvidia.com>
Message-Id: <20230417110343.138319-1-elic@nvidia.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent 6a8f57ae

drivers/vdpa/mlx5/net/mlx5_vnet.c

+114 −89
Original line number Diff line number Diff line
@@ -2298,6 +2298,113 @@ static void update_cvq_info(struct mlx5_vdpa_dev *mvdev) 
	}

}



static u8 query_vport_state(struct mlx5_core_dev *mdev, u8 opmod, u16 vport)

{

	u32 out[MLX5_ST_SZ_DW(query_vport_state_out)] = {};

	u32 in[MLX5_ST_SZ_DW(query_vport_state_in)] = {};

	int err;



	MLX5_SET(query_vport_state_in, in, opcode, MLX5_CMD_OP_QUERY_VPORT_STATE);

	MLX5_SET(query_vport_state_in, in, op_mod, opmod);

	MLX5_SET(query_vport_state_in, in, vport_number, vport);

	if (vport)

		MLX5_SET(query_vport_state_in, in, other_vport, 1);



	err = mlx5_cmd_exec_inout(mdev, query_vport_state, in, out);

	if (err)

		return 0;



	return MLX5_GET(query_vport_state_out, out, state);

}



static bool get_link_state(struct mlx5_vdpa_dev *mvdev)

{

	if (query_vport_state(mvdev->mdev, MLX5_VPORT_STATE_OP_MOD_VNIC_VPORT, 0) ==

	    VPORT_STATE_UP)

		return true;



	return false;

}



static void update_carrier(struct work_struct *work)

{

	struct mlx5_vdpa_wq_ent *wqent;

	struct mlx5_vdpa_dev *mvdev;

	struct mlx5_vdpa_net *ndev;



	wqent = container_of(work, struct mlx5_vdpa_wq_ent, work);

	mvdev = wqent->mvdev;

	ndev = to_mlx5_vdpa_ndev(mvdev);

	if (get_link_state(mvdev))

		ndev->config.status |= cpu_to_mlx5vdpa16(mvdev, VIRTIO_NET_S_LINK_UP);

	else

		ndev->config.status &= cpu_to_mlx5vdpa16(mvdev, ~VIRTIO_NET_S_LINK_UP);



	if (ndev->config_cb.callback)

		ndev->config_cb.callback(ndev->config_cb.private);



	kfree(wqent);

}



static int queue_link_work(struct mlx5_vdpa_net *ndev)

{

	struct mlx5_vdpa_wq_ent *wqent;



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

	if (!wqent)

		return -ENOMEM;



	wqent->mvdev = &ndev->mvdev;

	INIT_WORK(&wqent->work, update_carrier);

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

	return 0;

}



static int event_handler(struct notifier_block *nb, unsigned long event, void *param)

{

	struct mlx5_vdpa_net *ndev = container_of(nb, struct mlx5_vdpa_net, nb);

	struct mlx5_eqe *eqe = param;

	int ret = NOTIFY_DONE;



	if (event == MLX5_EVENT_TYPE_PORT_CHANGE) {

		switch (eqe->sub_type) {

		case MLX5_PORT_CHANGE_SUBTYPE_DOWN:

		case MLX5_PORT_CHANGE_SUBTYPE_ACTIVE:

			if (queue_link_work(ndev))

				return NOTIFY_DONE;



			ret = NOTIFY_OK;

			break;

		default:

			return NOTIFY_DONE;

		}

		return ret;

	}

	return ret;

}



static void register_link_notifier(struct mlx5_vdpa_net *ndev)

{

	if (!(ndev->mvdev.actual_features & BIT_ULL(VIRTIO_NET_F_STATUS)))

		return;



	ndev->nb.notifier_call = event_handler;

	mlx5_notifier_register(ndev->mvdev.mdev, &ndev->nb);

	ndev->nb_registered = true;

	queue_link_work(ndev);

}



static void unregister_link_notifier(struct mlx5_vdpa_net *ndev)

{

	if (!ndev->nb_registered)

		return;



	ndev->nb_registered = false;

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

	if (ndev->mvdev.wq)

		flush_workqueue(ndev->mvdev.wq);

}



static int mlx5_vdpa_set_driver_features(struct vdpa_device *vdev, u64 features)

{

	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
@@ -2567,10 +2674,11 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status) 
				mlx5_vdpa_warn(mvdev, "failed to setup control VQ vring\n");

				goto err_setup;

			}

			register_link_notifier(ndev);

			err = setup_driver(mvdev);

			if (err) {

				mlx5_vdpa_warn(mvdev, "failed to setup driver\n");

				goto err_setup;

				goto err_driver;

			}

		} else {

			mlx5_vdpa_warn(mvdev, "did not expect DRIVER_OK to be cleared\n");
@@ -2582,6 +2690,8 @@ static void mlx5_vdpa_set_status(struct vdpa_device *vdev, u8 status) 
	up_write(&ndev->reslock);

	return;



err_driver:

	unregister_link_notifier(ndev);

err_setup:

	mlx5_vdpa_destroy_mr(&ndev->mvdev);

	ndev->mvdev.status |= VIRTIO_CONFIG_S_FAILED;
@@ -2607,6 +2717,7 @@ static int mlx5_vdpa_reset(struct vdpa_device *vdev) 
	mlx5_vdpa_info(mvdev, "performing device reset\n");



	down_write(&ndev->reslock);

	unregister_link_notifier(ndev);

	teardown_driver(ndev);

	clear_vqs_ready(ndev);

	mlx5_vdpa_destroy_mr(&ndev->mvdev);
@@ -2861,9 +2972,7 @@ static int mlx5_vdpa_suspend(struct vdpa_device *vdev) 
	mlx5_vdpa_info(mvdev, "suspending device\n");



	down_write(&ndev->reslock);

	ndev->nb_registered = false;

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

	flush_workqueue(ndev->mvdev.wq);

	unregister_link_notifier(ndev);

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

		mvq = &ndev->vqs[i];

		suspend_vq(ndev, mvq);
@@ -3000,84 +3109,6 @@ struct mlx5_vdpa_mgmtdev { 
	struct mlx5_vdpa_net *ndev;

};



static u8 query_vport_state(struct mlx5_core_dev *mdev, u8 opmod, u16 vport)

{

	u32 out[MLX5_ST_SZ_DW(query_vport_state_out)] = {};

	u32 in[MLX5_ST_SZ_DW(query_vport_state_in)] = {};

	int err;



	MLX5_SET(query_vport_state_in, in, opcode, MLX5_CMD_OP_QUERY_VPORT_STATE);

	MLX5_SET(query_vport_state_in, in, op_mod, opmod);

	MLX5_SET(query_vport_state_in, in, vport_number, vport);

	if (vport)

		MLX5_SET(query_vport_state_in, in, other_vport, 1);



	err = mlx5_cmd_exec_inout(mdev, query_vport_state, in, out);

	if (err)

		return 0;



	return MLX5_GET(query_vport_state_out, out, state);

}



static bool get_link_state(struct mlx5_vdpa_dev *mvdev)

{

	if (query_vport_state(mvdev->mdev, MLX5_VPORT_STATE_OP_MOD_VNIC_VPORT, 0) ==

	    VPORT_STATE_UP)

		return true;



	return false;

}



static void update_carrier(struct work_struct *work)

{

	struct mlx5_vdpa_wq_ent *wqent;

	struct mlx5_vdpa_dev *mvdev;

	struct mlx5_vdpa_net *ndev;



	wqent = container_of(work, struct mlx5_vdpa_wq_ent, work);

	mvdev = wqent->mvdev;

	ndev = to_mlx5_vdpa_ndev(mvdev);

	if (get_link_state(mvdev))

		ndev->config.status |= cpu_to_mlx5vdpa16(mvdev, VIRTIO_NET_S_LINK_UP);

	else

		ndev->config.status &= cpu_to_mlx5vdpa16(mvdev, ~VIRTIO_NET_S_LINK_UP);



	if (ndev->nb_registered && ndev->config_cb.callback)

		ndev->config_cb.callback(ndev->config_cb.private);



	kfree(wqent);

}



static int event_handler(struct notifier_block *nb, unsigned long event, void *param)

{

	struct mlx5_vdpa_net *ndev = container_of(nb, struct mlx5_vdpa_net, nb);

	struct mlx5_eqe *eqe = param;

	int ret = NOTIFY_DONE;

	struct mlx5_vdpa_wq_ent *wqent;



	if (event == MLX5_EVENT_TYPE_PORT_CHANGE) {

		if (!(ndev->mvdev.actual_features & BIT_ULL(VIRTIO_NET_F_STATUS)))

			return NOTIFY_DONE;

		switch (eqe->sub_type) {

		case MLX5_PORT_CHANGE_SUBTYPE_DOWN:

		case MLX5_PORT_CHANGE_SUBTYPE_ACTIVE:

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

			if (!wqent)

				return NOTIFY_DONE;



			wqent->mvdev = &ndev->mvdev;

			INIT_WORK(&wqent->work, update_carrier);

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

			ret = NOTIFY_OK;

			break;

		default:

			return NOTIFY_DONE;

		}

		return ret;

	}

	return ret;

}



static int config_func_mtu(struct mlx5_core_dev *mdev, u16 mtu)

{

	int inlen = MLX5_ST_SZ_BYTES(modify_nic_vport_context_in);
@@ -3258,9 +3289,6 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name, 
		goto err_res2;

	}



	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)
@@ -3294,10 +3322,7 @@ static void mlx5_vdpa_dev_del(struct vdpa_mgmt_dev *v_mdev, struct vdpa_device * 


	mlx5_vdpa_remove_debugfs(ndev->debugfs);

	ndev->debugfs = NULL;

	if (ndev->nb_registered) {

		ndev->nb_registered = false;

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

	}

	unregister_link_notifier(ndev);

	wq = mvdev->wq;

	mvdev->wq = NULL;

	destroy_workqueue(wq);