From cae15c2ed8e6e058bd5e32de292ab7982640161e Mon Sep 17 00:00:00 2001 From: Eli Cohen Date: Thu, 14 Jul 2022 14:39:26 +0300 Subject: 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: Eli Cohen Message-Id: <20220714113927.85729-2-elic@nvidia.com> Signed-off-by: Michael S. Tsirkin --- drivers/vdpa/mlx5/net/mlx5_vnet.c | 83 +++++++++++++++++++++++++++++++++++++-- 1 file changed, 80 insertions(+), 3 deletions(-) (limited to 'drivers/vdpa') diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c index 99bbbf38c8b1..a476e06476f6 100644 --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c @@ -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 @@ err_cmd: 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 @@ out_err: 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; - mlx5_notifier_unregister(mvdev->mdev, &ndev->nb); + if (ndev->nb_registered) { + mlx5_notifier_unregister(mvdev->mdev, &ndev->nb); + ndev->nb_registered = false; + } wq = mvdev->wq; mvdev->wq = NULL; destroy_workqueue(wq); -- cgit v1.2.3