[PATCH] vdpa/mlx5: Add support for doorbell bypassing

[Eli Cohen <elic@nvidia.com>]

Implement mlx5_get_vq_notification() to return the doorbell address.
Size is set to one system page as required.

Signed-off-by: Eli Cohen <elic@nvidia.com>
---
 drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 +
 drivers/vdpa/mlx5/core/resources.c | 1 +
 drivers/vdpa/mlx5/net/mlx5_vnet.c  | 6 ++++++
 3 files changed, 8 insertions(+)

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index b6cc53ba980c..49de62cda598 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -41,6 +41,7 @@ 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;
diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
index 6521cbd0f5c2..665f8fc1710f 100644
--- a/drivers/vdpa/mlx5/core/resources.c
+++ b/drivers/vdpa/mlx5/core/resources.c
@@ -247,6 +247,7 @@ 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) {
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 10c5fef3c020..680751074d2a 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1865,8 +1865,14 @@ 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;
+
+	ndev = to_mlx5_vdpa_ndev(mvdev);
 
+	ret.addr = (phys_addr_t)ndev->mvdev.res.phys_kick_addr;
+	ret.size = PAGE_SIZE;
 	return ret;
 }
 
-- 
2.30.1