[PATCH 1/2] vdpa: support per virtqueue max queue size
From: Jason Wang
Date: Mon Jul 05 2021 - 03:19:28 EST
Virtio spec allows the device to specify the per virtqueue max queue
size. vDPA needs to adapt to this flexibility. E.g Qemu advertise a
small control virtqueue for virtio-net.
So this patch adds a index parameter to get_vq_num_max bus operations
for the device to report its per virtqueue max queue size.
Both VHOST_VDPA_GET_VRING_NUM and VDPA_ATTR_DEV_MAX_VQ_SIZE assume a
global maximum size. So we iterate all the virtqueues to return the
minimal size in this case. Actually, the VHOST_VDPA_GET_VRING_NUM is
not a must for the userspace. Userspace may choose to check the
VHOST_SET_VRING_NUM for proving or validating the maximum virtqueue
size. Anyway, we can invent a per vq version of
VHOST_VDPA_GET_VRING_NUM in the future if it's necessary.
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/vdpa/ifcvf/ifcvf_main.c | 2 +-
drivers/vdpa/mlx5/net/mlx5_vnet.c | 2 +-
drivers/vdpa/vdpa.c | 22 +++++++++++++++++++++-
drivers/vdpa/vdpa_sim/vdpa_sim.c | 2 +-
drivers/vdpa/virtio_pci/vp_vdpa.c | 2 +-
drivers/vhost/vdpa.c | 9 ++++++---
drivers/virtio/virtio_vdpa.c | 2 +-
include/linux/vdpa.h | 5 ++++-
8 files changed, 36 insertions(+), 10 deletions(-)
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index ab0ab5cf0f6e..646b340db2af 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -254,7 +254,7 @@ static void ifcvf_vdpa_set_status(struct vdpa_device *vdpa_dev, u8 status)
ifcvf_set_status(vf, status);
}
-static u16 ifcvf_vdpa_get_vq_num_max(struct vdpa_device *vdpa_dev)
+static u16 ifcvf_vdpa_get_vq_num_max(struct vdpa_device *vdpa_dev, u16 qid)
{
return IFCVF_QUEUE_MAX;
}
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index dda5dc6f7737..afd6114d07b0 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -1584,7 +1584,7 @@ static void mlx5_vdpa_set_config_cb(struct vdpa_device *vdev, struct vdpa_callba
}
#define MLX5_VDPA_MAX_VQ_ENTRIES 256
-static u16 mlx5_vdpa_get_vq_num_max(struct vdpa_device *vdev)
+static u16 mlx5_vdpa_get_vq_num_max(struct vdpa_device *vdev, u16 idx)
{
return MLX5_VDPA_MAX_VQ_ENTRIES;
}
diff --git a/drivers/vdpa/vdpa.c b/drivers/vdpa/vdpa.c
index bb3f1d1f0422..d77d59811389 100644
--- a/drivers/vdpa/vdpa.c
+++ b/drivers/vdpa/vdpa.c
@@ -239,6 +239,26 @@ void vdpa_unregister_driver(struct vdpa_driver *drv)
}
EXPORT_SYMBOL_GPL(vdpa_unregister_driver);
+/**
+ * vdpa_get_vq_num_max - get the maximum virtqueue size
+ * @vdev: vdpa device
+ */
+u16 vdpa_get_vq_num_max(struct vdpa_device *vdev)
+{
+ const struct vdpa_config_ops *ops = vdev->config;
+ u16 s, size = ops->get_vq_num_max(vdev, 0);
+ int i;
+
+ for (i = 1; i < vdev->nvqs; i++) {
+ s = ops->get_vq_num_max(vdev, i);
+ if (s && s < size)
+ size = s;
+ }
+
+ return size;
+}
+EXPORT_SYMBOL_GPL(vdpa_get_vq_num_max);
+
/**
* vdpa_mgmtdev_register - register a vdpa management device
*
@@ -502,7 +522,7 @@ vdpa_dev_fill(struct vdpa_device *vdev, struct sk_buff *msg, u32 portid, u32 seq
device_id = vdev->config->get_device_id(vdev);
vendor_id = vdev->config->get_vendor_id(vdev);
- max_vq_size = vdev->config->get_vq_num_max(vdev);
+ max_vq_size = vdpa_get_vq_num_max(vdev);
err = -EMSGSIZE;
if (nla_put_string(msg, VDPA_ATTR_DEV_NAME, dev_name(&vdev->dev)))
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 98f793bc9376..49e29056f164 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -422,7 +422,7 @@ static void vdpasim_set_config_cb(struct vdpa_device *vdpa,
/* We don't support config interrupt */
}
-static u16 vdpasim_get_vq_num_max(struct vdpa_device *vdpa)
+static u16 vdpasim_get_vq_num_max(struct vdpa_device *vdpa, u16 idx)
{
return VDPASIM_QUEUE_MAX;
}
diff --git a/drivers/vdpa/virtio_pci/vp_vdpa.c b/drivers/vdpa/virtio_pci/vp_vdpa.c
index c76ebb531212..2926641fb586 100644
--- a/drivers/vdpa/virtio_pci/vp_vdpa.c
+++ b/drivers/vdpa/virtio_pci/vp_vdpa.c
@@ -195,7 +195,7 @@ static void vp_vdpa_set_status(struct vdpa_device *vdpa, u8 status)
vp_vdpa_free_irq(vp_vdpa);
}
-static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa)
+static u16 vp_vdpa_get_vq_num_max(struct vdpa_device *vdpa, u16 qid)
{
return VP_VDPA_QUEUE_MAX;
}
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index fb41db3da611..c9ec395b8c42 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -289,11 +289,14 @@ static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep)
static long vhost_vdpa_get_vring_num(struct vhost_vdpa *v, u16 __user *argp)
{
- struct vdpa_device *vdpa = v->vdpa;
- const struct vdpa_config_ops *ops = vdpa->config;
u16 num;
- num = ops->get_vq_num_max(vdpa);
+ /*
+ * VHOST_VDPA_GET_VRING_NUM asssumes a global max virtqueue
+ * size. So we need to iterate all the virtqueue and return
+ * the minimal one here.
+ */
+ num = vdpa_get_vq_num_max(v->vdpa);
if (copy_to_user(argp, &num, sizeof(num)))
return -EFAULT;
diff --git a/drivers/virtio/virtio_vdpa.c b/drivers/virtio/virtio_vdpa.c
index e28acf482e0c..a43bd5ec5ac6 100644
--- a/drivers/virtio/virtio_vdpa.c
+++ b/drivers/virtio/virtio_vdpa.c
@@ -158,7 +158,7 @@ virtio_vdpa_setup_vq(struct virtio_device *vdev, unsigned int index,
if (!info)
return ERR_PTR(-ENOMEM);
- num = ops->get_vq_num_max(vdpa);
+ num = ops->get_vq_num_max(vdpa, index);
if (num == 0) {
err = -ENOENT;
goto error_new_virtqueue;
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index f311d227aa1b..0f8977a54783 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h
@@ -137,6 +137,7 @@ struct vdpa_iova_range {
* @cb: virtio-vdev interrupt callback structure
* @get_vq_num_max: Get the max size of virtqueue
* @vdev: vdpa device
+ * @idx: virtqueue index
* Returns u16: max size of virtqueue
* @get_device_id: Get virtio device id
* @vdev: vdpa device
@@ -229,7 +230,7 @@ struct vdpa_config_ops {
int (*set_features)(struct vdpa_device *vdev, u64 features);
void (*set_config_cb)(struct vdpa_device *vdev,
struct vdpa_callback *cb);
- u16 (*get_vq_num_max)(struct vdpa_device *vdev);
+ u16 (*get_vq_num_max)(struct vdpa_device *vdev, u16 idx);
u32 (*get_device_id)(struct vdpa_device *vdev);
u32 (*get_vendor_id)(struct vdpa_device *vdev);
u8 (*get_status)(struct vdpa_device *vdev);
@@ -270,6 +271,8 @@ void vdpa_unregister_device(struct vdpa_device *vdev);
int _vdpa_register_device(struct vdpa_device *vdev, int nvqs);
void _vdpa_unregister_device(struct vdpa_device *vdev);
+u16 vdpa_get_vq_num_max(struct vdpa_device *vdev);
+
/**
* struct vdpa_driver - operations for a vDPA driver
* @driver: underlying device driver
--
2.25.1