Commit b57c46cb authored by Eli Cohen's avatar Eli Cohen Committed by Michael S. Tsirkin
Browse files

vdpa/mlx5: Add support for doorbell bypassing 



Implement mlx5_get_vq_notification() to return the doorbell address.
Since the notification area is mapped to userspace, make sure that the
BAR size is at least PAGE_SIZE large.

Signed-off-by: default avatarEli Cohen <elic@nvidia.com>
Link: https://lore.kernel.org/r/20210603081153.5750-1-elic@nvidia.com


Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Acked-by: default avatarJason Wang <jasowang@redhat.com>
parent a7766ef1

drivers/vdpa/mlx5/core/mlx5_vdpa.h

+1 −0
Original line number Diff line number Diff line
@@ -42,6 +42,7 @@ struct mlx5_vdpa_resources { 
	u32 pdn;

	struct mlx5_uars_page *uar;

	void __iomem *kick_addr;

	u64 phys_kick_addr;

	u16 uid;

	u32 null_mkey;

	bool valid;

drivers/vdpa/mlx5/core/resources.c

+1 −0
Original line number Diff line number Diff line
@@ -253,6 +253,7 @@ int mlx5_vdpa_alloc_resources(struct mlx5_vdpa_dev *mvdev) 
		goto err_key;



	kick_addr = mdev->bar_addr + offset;

	res->phys_kick_addr = kick_addr;



	res->kick_addr = ioremap(kick_addr, PAGE_SIZE);

	if (!res->kick_addr) {

drivers/vdpa/mlx5/net/mlx5_vnet.c

+14 −0
Original line number Diff line number Diff line
@@ -1876,8 +1876,22 @@ static void mlx5_vdpa_free(struct vdpa_device *vdev) 


static struct vdpa_notification_area mlx5_get_vq_notification(struct vdpa_device *vdev, u16 idx)

{

	struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);

	struct vdpa_notification_area ret = {};

	struct mlx5_vdpa_net *ndev;

	phys_addr_t addr;



	/* If SF BAR size is smaller than PAGE_SIZE, do not use direct

	 * notification to avoid the risk of mapping pages that contain BAR of more

	 * than one SF

	 */

	if (MLX5_CAP_GEN(mvdev->mdev, log_min_sf_size) + 12 < PAGE_SHIFT)

		return ret;



	ndev = to_mlx5_vdpa_ndev(mvdev);

	addr = (phys_addr_t)ndev->mvdev.res.phys_kick_addr;

	ret.addr = addr;

	ret.size = PAGE_SIZE;

	return ret;

}