2021-06-03 08:15:40

by Eli Cohen

Subject: [PATCH v2] 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: Eli Cohen <[email protected]>
---
v0 --> v1:
Make sure SF bar size is not smaller than PAGE_SIZE
v1 --> v2:
Remove test on addr alignment since it's alrady done by the caller.

drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 +
drivers/vdpa/mlx5/core/resources.c | 1 +
drivers/vdpa/mlx5/net/mlx5_vnet.c | 14 ++++++++++++++
3 files changed, 16 insertions(+)

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index 09a16a3d1b2a..0002b2136b48 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -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;
diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
index 836ab9ef0fa6..d4606213f88a 100644
--- a/drivers/vdpa/mlx5/core/resources.c
+++ b/drivers/vdpa/mlx5/core/resources.c
@@ -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) {
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 689d3fa61e08..bc33f2c523d3 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1879,8 +1879,22 @@ 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;
}

--
2.31.1

2021-06-04 02:34:07

by Jason Wang

Subject: Re: [PATCH v2] vdpa/mlx5: Add support for doorbell bypassing

?? 2021/6/3 ????4:11, Eli Cohen д??:
> 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: Eli Cohen <[email protected]>
> ---
> v0 --> v1:
> Make sure SF bar size is not smaller than PAGE_SIZE
> v1 --> v2:
> Remove test on addr alignment since it's alrady done by the caller.


Acked-by: Jason Wang <[email protected]>


>
> drivers/vdpa/mlx5/core/mlx5_vdpa.h | 1 +
> drivers/vdpa/mlx5/core/resources.c | 1 +
> drivers/vdpa/mlx5/net/mlx5_vnet.c | 14 ++++++++++++++
> 3 files changed, 16 insertions(+)
>
> diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
> index 09a16a3d1b2a..0002b2136b48 100644
> --- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
> +++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
> @@ -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;
> diff --git a/drivers/vdpa/mlx5/core/resources.c b/drivers/vdpa/mlx5/core/resources.c
> index 836ab9ef0fa6..d4606213f88a 100644
> --- a/drivers/vdpa/mlx5/core/resources.c
> +++ b/drivers/vdpa/mlx5/core/resources.c
> @@ -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) {
> diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> index 689d3fa61e08..bc33f2c523d3 100644
> --- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
> +++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
> @@ -1879,8 +1879,22 @@ 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;
> }
>