Subject: Re: [PATCH 2/2] IFC VDPA layer

From: Jason Wang <[email-masked]>
Date: Wed, 6 Nov 2019 05:39:52 -0500 (EST)

----- Original Message -----
> This commit introduced IFC operations for vdpa, which complys to
> virtio_mdev and vhost_mdev interfaces, handles IFC VF
> initialization, configuration and removal.
> 
> Signed-off-by: Zhu Lingshan <[email-masked]>
> ---
>  drivers/vhost/ifcvf/ifcvf_main.c | 605
>  +++++++++++++++++++++++++++++++++++++++
>  1 file changed, 605 insertions(+)
>  create mode 100644 drivers/vhost/ifcvf/ifcvf_main.c
> 
> diff --git a/drivers/vhost/ifcvf/ifcvf_main.c
> b/drivers/vhost/ifcvf/ifcvf_main.c
> new file mode 100644
> index 0000000..7165457
> --- /dev/null
> +++ b/drivers/vhost/ifcvf/ifcvf_main.c
> @@ -0,0 +1,605 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2019 Intel Corporation.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/module.h>
> +#include <linux/mdev.h>
> +#include <linux/pci.h>
> +#include <linux/sysfs.h>
> +#include "ifcvf_base.h"
> +
> +#define VERSION_STRING	"0.1"
> +#define DRIVER_AUTHOR	"Intel Corporation"
> +#define IFCVF_DRIVER_NAME	"ifcvf"
> +
> +static struct ifcvf_hw *mdev_to_vf(struct mdev_device *mdev)
> +{
> +	struct ifcvf_asapter *adapter = mdev_get_drvdata(mdev);
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +
> +	return vf;
> +}
> +
> +static irqreturn_t ifcvf_intr_handler(int irq, void *arg)
> +{
> +	struct vring_info *vring = arg;
> +
> +	if (vring->cb.callback)
> +		return vring->cb.callback(vring->cb.private);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static u64 ifcvf_mdev_get_features(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return ifcvf_get_features(vf);
> +}
> +
> +static int ifcvf_mdev_set_features(struct mdev_device *mdev, u64 features)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->req_features = features;
> +
> +	return 0;
> +}
> +
> +static u64 ifcvf_mdev_get_vq_state(struct mdev_device *mdev, u16 qid)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +	u16 last_avail_idx;
> +
> +	last_avail_idx = *(u16 *)(vf->lm_cfg + IFCVF_LM_RING_STATE_OFFSET +
> +			 (qid / 2) * IFCVF_LM_CFG_SIZE + (qid % 2) * 4);
> +

Similar to the comment of previous patch, it's better to have a
structure for lm_cfg.

> +	return last_avail_idx;
> +}
> +
> +static int ifcvf_mdev_set_vq_state(struct mdev_device *mdev, u16 qid, u64
> num)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[qid].last_avail_idx = num;
> +
> +	return 0;
> +}
> +
> +static int ifcvf_mdev_set_vq_address(struct mdev_device *mdev, u16 idx,
> +				     u64 desc_area, u64 driver_area,
> +				     u64 device_area)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[idx].desc = desc_area;
> +	vf->vring[idx].avail = driver_area;
> +	vf->vring[idx].used = device_area;
> +
> +	return 0;
> +}
> +
> +static void ifcvf_mdev_set_vq_num(struct mdev_device *mdev, u16 qid, u32
> num)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[qid].size = num;
> +}
> +
> +static void ifcvf_mdev_set_vq_ready(struct mdev_device *mdev,
> +				    u16 qid, bool ready)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[qid].ready = ready;

There should be a "iowrite16(1, &cfg->queue_enable)" here. And there's
probably no need to store ready in vring in this case.

> +}
> +
> +static bool ifcvf_mdev_get_vq_ready(struct mdev_device *mdev, u16 qid)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return vf->vring[qid].ready;

And the status should be read from cfg->queue_enable.

> +}
> +
> +static void ifcvf_mdev_set_vq_cb(struct mdev_device *mdev, u16 idx,
> +				 struct virtio_mdev_callback *cb)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	vf->vring[idx].cb = *cb;
> +}
> +
> +static void ifcvf_mdev_kick_vq(struct mdev_device *mdev, u16 idx)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	ifcvf_notify_queue(vf, idx);
> +}
> +
> +static u8 ifcvf_mdev_get_status(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return ifcvf_get_status(vf);
> +}
> +
> +static u32 ifcvf_mdev_get_generation(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return ioread8(&vf->common_cfg->config_generation);
> +}
> +
> +static u32 ifcvf_mdev_get_device_id(struct mdev_device *mdev)
> +{
> +	return VIRTIO_ID_NET;
> +}
> +
> +static u32 ifcvf_mdev_get_vendor_id(struct mdev_device *mdev)
> +{
> +	return IFCVF_VENDOR_ID;
> +}
> +
> +static u16 ifcvf_mdev_get_vq_align(struct mdev_device *mdev)
> +{
> +	return IFCVF_QUEUE_ALIGNMENT;
> +}
> +
> +static u64 ifcvf_mdev_get_mdev_features(struct mdev_device *mdev)
> +{
> +	return VIRTIO_MDEV_F_VERSION_1;
> +}

We've decide to remove this API.

> +
> +static int ifcvf_start_datapath(void *private)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
> +	struct ifcvf_adapter *ifcvf;
> +	int i, ret = 0;
> +
> +	ifcvf = container_of(vf, struct ifcvf_adapter, vf);
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		if (!vf->vring[i].ready) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, vring %d not ready.\n", i);
> +			return -EINVAL;
> +		}

This should be not related. Driver can choose to not start a virtqueue.

> +
> +		if (!vf->vring[i].size) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, vring %d size is zero.\n", i);
> +			return -EINVAL;
> +		}
> +
> +		if (!vf->vring[i].desc || !vf->vring[i].avail ||
> +			!vf->vring[i].used) {
> +			IFC_ERR(ifcvf->dev,
> +				"Failed to start datapath, "
> +				"invaild value for vring %d desc,"
> +				"avail_idx or usex_idx.\n", i);
> +			return -EINVAL;
> +		}
> +	}
> +
> +	vf->nr_vring = i;
> +	ret = ifcvf_start_hw(vf);

So basically there's no need for ifcvf_start_hw() to care about vq
enablement, virtio core will take care of that through set_vq_ready().

> +
> +	return ret;
> +}
> +
> +static int ifcvf_stop_datapath(void *private)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(private);
> +	int i;
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUES; i++)
> +		vf->vring[i].cb.callback = NULL;
> +
> +	ifcvf_stop_hw(vf);
> +
> +	return 0;
> +}
> +
> +static void ifcvf_reset_vring(struct ifcvf_adapter *adapter)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +	struct virtio_pci_common_cfg *cfg;
> +	u8 *lm_cfg;
> +	int i;
> +
> +	cfg = vf->common_cfg;
> +	lm_cfg = vf->lm_cfg;
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		vf->vring[i].last_used_idx = 0;
> +		vf->vring[i].last_avail_idx = 0;
> +		vf->vring[i].desc = 0;
> +		vf->vring[i].avail = 0;
> +		vf->vring[i].used = 0;
> +		vf->vring[i].ready = 0;
> +		vf->vring->cb.callback = NULL;
> +		vf->vring->cb.private = NULL;
> +
> +	}
> +
> +	ifcvf_reset(vf);

So virtio-pci call vp_synchornize_vectors(), do need someting similar
here (I mean in ifcvf_reset())?

> +}
> +
> +static void ifcvf_mdev_set_status(struct mdev_device *mdev, u8 status)
> +{
> +	struct ifcvf_adapter *adapter = mdev_get_drvdata(mdev);
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +	int ret = 0;
> +
> +	if (status == 0) {
> +		ifcvf_stop_datapath(adapter);
> +		ifcvf_reset_vring(adapter);
> +		return;
> +	}
> +
> +	if (status & VIRTIO_CONFIG_S_DRIVER_OK) {
> +		ret = ifcvf_start_datapath(adapter);

If device support VIRTIO_CONFIG_S_DRIVER_OK, having something like
start_datapath here looks wired.

If it just to setup the virtqueue etc, can we simply move them to e.g
set_vq_num, set_vq_address, etc?

> +
> +		if (ret)
> +			IFC_ERR(adapter->dev, "Failed to set mdev status %u.\n",
> +				status);
> +	}
> +
> +	ifcvf_set_status(vf, status);
> +}
> +
> +static u16 ifcvf_mdev_get_vq_num_max(struct mdev_device *mdev)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	return vf->vring[0].size;

It looks to me the only case that size is set is from
ifcvf_mdev_set_vq_num()? So I don't get how is this supposed to
work. I belive this should be a query for the hardware or a at least a
macro?

> +}
> +static void ifcvf_mdev_get_config(struct mdev_device *mdev, unsigned int
> offset,
> +			     void *buf, unsigned int len)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
> +	ifcvf_read_net_config(vf, offset, buf, len);
> +}
> +
> +static void ifcvf_mdev_set_config(struct mdev_device *mdev, unsigned int
> offset,
> +			     const void *buf, unsigned int len)
> +{
> +	struct ifcvf_hw *vf = mdev_to_vf(mdev);
> +
> +	WARN_ON(offset + len > sizeof(struct ifcvf_net_config));
> +	ifcvf_write_net_config(vf, offset, buf, len);
> +}
> +
> +static struct virtio_mdev_device_ops ifc_mdev_ops = {
> +	.get_features  = ifcvf_mdev_get_features,
> +	.set_features  = ifcvf_mdev_set_features,
> +	.get_status    = ifcvf_mdev_get_status,
> +	.set_status    = ifcvf_mdev_set_status,
> +	.get_vq_num_max = ifcvf_mdev_get_vq_num_max,
> +	.get_vq_state   = ifcvf_mdev_get_vq_state,
> +	.set_vq_state   = ifcvf_mdev_set_vq_state,
> +	.set_vq_cb      = ifcvf_mdev_set_vq_cb,
> +	.set_vq_ready   = ifcvf_mdev_set_vq_ready,
> +	.get_vq_ready	= ifcvf_mdev_get_vq_ready,
> +	.set_vq_num     = ifcvf_mdev_set_vq_num,
> +	.set_vq_address = ifcvf_mdev_set_vq_address,
> +	.kick_vq        = ifcvf_mdev_kick_vq,
> +	.get_generation	= ifcvf_mdev_get_generation,
> +	.get_device_id	= ifcvf_mdev_get_device_id,
> +	.get_vendor_id	= ifcvf_mdev_get_vendor_id,
> +	.get_vq_align	= ifcvf_mdev_get_vq_align,
> +	.get_config	= ifcvf_mdev_get_config,
> +	.set_config	= ifcvf_mdev_set_config,
> +	.get_mdev_features = ifcvf_mdev_get_mdev_features,

set_config_cb needs to be implemented since you claim to support VIRTIO_NET_F_STATUS.

> +};
> +
> +static int ifcvf_init_msix(struct ifcvf_adapter *adapter)
> +{
> +	struct pci_dev *pdev = to_pci_dev(adapter->dev);
> +	struct ifcvf_hw *vf = &adapter->vf;
> +	int vector, i, ret, irq;
> +
> +	ret = pci_alloc_irq_vectors(pdev, IFCVF_MAX_INTR,
> +				    IFCVF_MAX_INTR, PCI_IRQ_MSIX);
> +	if (ret < 0) {
> +		IFC_ERR(adapter->dev, "Failed to alloc irq vectors.\n");
> +		return ret;
> +	}
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		vector = i + IFCVF_MSI_QUEUE_OFF;
> +		irq = pci_irq_vector(pdev, vector);
> +		ret = request_irq(irq, ifcvf_intr_handler, 0,
> +				pci_name(pdev), &vf->vring[i]);
> +		if (ret) {
> +			IFC_ERR(adapter->dev,
> +				"Failed to request irq for vq %d.\n", i);
> +			return ret;
> +		}
> +	}

Need allocate config interrupt here as well.

> +
> +	return 0;
> +}
> +
> +static void ifcvf_destroy_adapter(struct ifcvf_adapter *adapter)
> +{
> +	struct ifcvf_hw *vf = IFC_PRIVATE_TO_VF(adapter);
> +	struct pci_dev *pdev = to_pci_dev(adapter->dev);
> +	int i, vector, irq;
> +
> +	for (i = 0; i < IFCVF_MAX_QUEUE_PAIRS * 2; i++) {
> +		vector = i + IFCVF_MSI_QUEUE_OFF;
> +		irq = pci_irq_vector(pdev, vector);
> +		free_irq(irq, &vf->vring[i]);
> +	}
> +}
> +
> +static ssize_t name_show(struct kobject *kobj, struct device *dev, char
> *buf)
> +{
> +	const char *name = "vhost accelerator (virtio ring compatible)";
> +

I believe something like "IFCVF vhost/virtio accelerator" is better?

> +	return sprintf(buf, "%s\n", name);
> +}
> +MDEV_TYPE_ATTR_RO(name);
> +
> +static ssize_t device_api_show(struct kobject *kobj, struct device *dev,
> +			       char *buf)
> +{
> +	return sprintf(buf, "%s\n", VIRTIO_MDEV_DEVICE_API_STRING);
> +}
> +MDEV_TYPE_ATTR_RO(device_api);
> +
> +static ssize_t available_instances_show(struct kobject *kobj,
> +					struct device *dev, char *buf)
> +{
> +	struct pci_dev *pdev;
> +	struct ifcvf_adapter *adapter;
> +
> +	pdev = to_pci_dev(dev);
> +	adapter = pci_get_drvdata(pdev);
> +
> +	return sprintf(buf, "%d\n", adapter->mdev_count);
> +}
> +
> +MDEV_TYPE_ATTR_RO(available_instances);
> +
> +static ssize_t type_show(struct kobject *kobj,
> +			struct device *dev, char *buf)
> +{
> +	return sprintf(buf, "%s\n", "net");
> +}
> +
> +MDEV_TYPE_ATTR_RO(type);
> +
> +
> +static struct attribute *mdev_types_attrs[] = {
> +	&mdev_type_attr_name.attr,
> +	&mdev_type_attr_device_api.attr,
> +	&mdev_type_attr_available_instances.attr,
> +	&mdev_type_attr_type.attr,
> +	NULL,
> +};
> +
> +static struct attribute_group mdev_type_group_virtio = {
> +	.name  = "virtio_mdev",
> +	.attrs = mdev_types_attrs,
> +};
> +
> +static struct attribute_group mdev_type_group_vhost = {
> +	.name  = "vhost_mdev",
> +	.attrs = mdev_types_attrs,
> +};
> +
> +static struct attribute_group *mdev_type_groups[] = {
> +	&mdev_type_group_virtio,
> +	&mdev_type_group_vhost,
> +	NULL,
> +};
> +
> +const struct attribute_group *mdev_dev_groups[] = {
> +	NULL,
> +};
> +
> +static int ifcvf_mdev_create(struct kobject *kobj, struct mdev_device *mdev)
> +{
> +	struct device *dev = mdev_parent_dev(mdev);
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
> +	int ret = 0;
> +
> +	mutex_lock(&adapter->mdev_lock);
> +
> +	if (adapter->mdev_count < IFCVF_MDEV_LIMIT) {
> +		IFC_ERR(&pdev->dev,
> +			"Can not create mdev, reached limitation %d.\n",
> +			IFCVF_MDEV_LIMIT);
> +		ret = -EINVAL;
> +		goto out;
> +	}
> +
> +	if (!strcmp(kobj->name, "ifcvf-virtio_mdev"))
> +		mdev_set_virtio_ops(mdev, &ifc_mdev_ops);
> +
> +	if (!strcmp(kobj->name, "ifcvf-vhost_mdev"))
> +		mdev_set_vhost_ops(mdev, &ifc_mdev_ops);
> +
> +	mdev_set_drvdata(mdev, adapter);
> +	mdev_set_iommu_device(mdev_dev(mdev), dev);
> +	adapter->mdev_count--;
> +
> +out:
> +	mutex_unlock(&adapter->mdev_lock);
> +	return ret;
> +}
> +
> +static int ifcvf_mdev_remove(struct mdev_device *mdev)
> +{
> +	struct device *dev = mdev_parent_dev(mdev);
> +	struct pci_dev *pdev = to_pci_dev(dev);
> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
> +
> +	mutex_lock(&adapter->mdev_lock);
> +	adapter->mdev_count++;
> +	mutex_unlock(&adapter->mdev_lock);
> +
> +	return 0;
> +}
> +
> +static struct mdev_parent_ops ifcvf_mdev_fops = {
> +	.owner			= THIS_MODULE,
> +	.supported_type_groups	= mdev_type_groups,
> +	.mdev_attr_groups	= mdev_dev_groups,
> +	.create			= ifcvf_mdev_create,
> +	.remove			= ifcvf_mdev_remove,
> +};
> +
> +static int ifcvf_probe(struct pci_dev *pdev, const struct pci_device_id *id)
> +{
> +	struct device *dev = &pdev->dev;
> +	struct ifcvf_adapter *adapter;
> +	struct ifcvf_hw *vf;
> +	int ret, i;
> +
> +	adapter = kzalloc(sizeof(struct ifcvf_adapter), GFP_KERNEL);
> +
> +	if (adapter == NULL) {
> +		ret = -ENOMEM;
> +		goto fail;
> +	}
> +
> +	mutex_init(&adapter->mdev_lock);
> +	adapter->mdev_count = IFCVF_MDEV_LIMIT;
> +	adapter->dev = dev;
> +	pci_set_drvdata(pdev, adapter);
> +	ret = pci_enable_device(pdev);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev, "Failed to enable device.\n");
> +		goto free_adapter;
> +	}
> +
> +	ret = pci_request_regions(pdev, IFCVF_DRIVER_NAME);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev, "Failed to request MMIO region.\n");
> +		goto disable_device;
> +	}
> +
> +	pci_set_master(pdev);
> +	ret = ifcvf_init_msix(adapter);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev, "Failed to initialize MSIX.\n");
> +		goto free_msix;
> +	}
> +
> +	vf = &adapter->vf;
> +
> +	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
> +		vf->mem_resource[i].phys_addr = pci_resource_start(pdev, i);
> +		vf->mem_resource[i].len = pci_resource_len(pdev, i);
> +		if (!vf->mem_resource[i].len) {
> +			vf->mem_resource[i].addr = NULL;
> +			continue;
> +		}
> +
> +		vf->mem_resource[i].addr = pci_iomap_range(pdev, i, 0,
> +				vf->mem_resource[i].len);
> +		if (!vf->mem_resource[i].addr) {
> +			IFC_ERR(adapter->dev, "Failed to map IO resource %d\n",
> +				i);
> +			ret = -1;
> +			goto free_msix;
> +		}
> +	}
> +
> +	if (ifcvf_init_hw(vf, pdev) < 0) {
> +		ret = -1;
> +		goto destroy_adapter;
> +	}
> +
> +	ret = mdev_register_device(dev, &ifcvf_mdev_fops);
> +
> +	if (ret) {
> +		IFC_ERR(adapter->dev,  "Failed to register mdev device\n");
> +		goto destroy_adapter;
> +	}
> +
> +	return 0;
> +
> +destroy_adapter:
> +	ifcvf_destroy_adapter(adapter);
> +free_msix:
> +	pci_free_irq_vectors(pdev);
> +	pci_release_regions(pdev);
> +disable_device:
> +	pci_disable_device(pdev);
> +free_adapter:
> +	kfree(adapter);
> +fail:
> +	return ret;
> +}
> +
> +static void ifcvf_remove(struct pci_dev *pdev)
> +{
> +	struct ifcvf_adapter *adapter = pci_get_drvdata(pdev);
> +	struct device *dev = &pdev->dev;
> +	struct ifcvf_hw *vf;
> +	int i;
> +
> +	mdev_unregister_device(dev);
> +
> +	vf = &adapter->vf;
> +	for (i = 0; i < IFCVF_PCI_MAX_RESOURCE; i++) {
> +		if (vf->mem_resource[i].addr) {
> +			pci_iounmap(pdev, vf->mem_resource[i].addr);
> +			vf->mem_resource[i].addr = NULL;
> +		}
> +	}
> +
> +	ifcvf_destroy_adapter(adapter);
> +	pci_free_irq_vectors(pdev);
> +	pci_release_regions(pdev);
> +	pci_disable_device(pdev);
> +	kfree(adapter);
> +}
> +
> +static struct pci_device_id ifcvf_pci_ids[] = {
> +	{ PCI_DEVICE_SUB(IFCVF_VENDOR_ID,
> +			IFCVF_DEVICE_ID,
> +			IFCVF_SUBSYS_VENDOR_ID,
> +			IFCVF_SUBSYS_DEVICE_ID) },
> +	{ 0 },
> +};
> +MODULE_DEVICE_TABLE(pci, ifcvf_pci_ids);
> +
> +static struct pci_driver ifcvf_driver = {
> +	.name     = IFCVF_DRIVER_NAME,
> +	.id_table = ifcvf_pci_ids,
> +	.probe    = ifcvf_probe,
> +	.remove   = ifcvf_remove,
> +};
> +
> +static int __init ifcvf_init_module(void)
> +{
> +	int ret;
> +
> +	ret = pci_register_driver(&ifcvf_driver);
> +	return ret;
> +}
> +
> +static void __exit ifcvf_exit_module(void)
> +{
> +	pci_unregister_driver(&ifcvf_driver);
> +}

You probably can do something simpler thorugh module_pci_driver().

Thanks

> +
> +module_init(ifcvf_init_module);
> +module_exit(ifcvf_exit_module);
> +
> +MODULE_LICENSE("GPL v2");
> +MODULE_VERSION(VERSION_STRING);
> +MODULE_AUTHOR(DRIVER_AUTHOR);
> --
> 1.8.3.1
> 
>