Re: [PATCH v2 03/17] vdpa_sim: remove hard-coded virtq count

[Jason Wang <jasowang@redhat.com>]

On 2020/11/26 下午10:49, Stefano Garzarella wrote:
> From: Max Gurtovoy <mgurtovoy@nvidia.com>
>
> Add a new attribute that will define the number of virt queues to be
> created for the vdpasim device.
>
> Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
> [sgarzare: replace kmalloc_array() with kcalloc()]
> Signed-off-by: Stefano Garzarella <sgarzare@redhat.com>


Acked-by: Jason Wang <jasowang@redhat.com>


> ---
> v1:
> - use kcalloc() instead of kmalloc_array() since some function expects
>    variables initialized to zero
> ---
>   drivers/vdpa/vdpa_sim/vdpa_sim.c | 18 +++++++++++++-----
>   1 file changed, 13 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> index c6eaf62df8ec..ad72f7b1a4eb 100644
> --- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
> +++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
> @@ -57,7 +57,7 @@ static u64 vdpasim_features = (1ULL << VIRTIO_F_ANY_LAYOUT) |
>   /* State of each vdpasim device */
>   struct vdpasim {
>   	struct vdpa_device vdpa;
> -	struct vdpasim_virtqueue vqs[VDPASIM_VQ_NUM];
> +	struct vdpasim_virtqueue *vqs;
>   	struct work_struct work;
>   	/* spinlock to synchronize virtqueue state */
>   	spinlock_t lock;
> @@ -67,6 +67,7 @@ struct vdpasim {
>   	u32 status;
>   	u32 generation;
>   	u64 features;
> +	int nvqs;
>   	/* spinlock to synchronize iommu table */
>   	spinlock_t iommu_lock;
>   };
> @@ -131,7 +132,7 @@ static void vdpasim_reset(struct vdpasim *vdpasim)
>   {
>   	int i;
>   
> -	for (i = 0; i < VDPASIM_VQ_NUM; i++)
> +	for (i = 0; i < vdpasim->nvqs; i++)
>   		vdpasim_vq_reset(&vdpasim->vqs[i]);
>   
>   	spin_lock(&vdpasim->iommu_lock);
> @@ -337,7 +338,7 @@ static struct vdpasim *vdpasim_create(void)
>   	const struct vdpa_config_ops *ops;
>   	struct vdpasim *vdpasim;
>   	struct device *dev;
> -	int ret = -ENOMEM;
> +	int i, ret = -ENOMEM;
>   
>   	if (batch_mapping)
>   		ops = &vdpasim_net_batch_config_ops;
> @@ -348,6 +349,7 @@ static struct vdpasim *vdpasim_create(void)
>   	if (!vdpasim)
>   		goto err_alloc;
>   
> +	vdpasim->nvqs = VDPASIM_VQ_NUM;
>   	INIT_WORK(&vdpasim->work, vdpasim_work);
>   	spin_lock_init(&vdpasim->lock);
>   	spin_lock_init(&vdpasim->iommu_lock);
> @@ -358,6 +360,11 @@ static struct vdpasim *vdpasim_create(void)
>   		goto err_iommu;
>   	set_dma_ops(dev, &vdpasim_dma_ops);
>   
> +	vdpasim->vqs = kcalloc(vdpasim->nvqs, sizeof(struct vdpasim_virtqueue),
> +			       GFP_KERNEL);
> +	if (!vdpasim->vqs)
> +		goto err_iommu;
> +
>   	vdpasim->iommu = vhost_iotlb_alloc(2048, 0);
>   	if (!vdpasim->iommu)
>   		goto err_iommu;
> @@ -376,8 +383,8 @@ static struct vdpasim *vdpasim_create(void)
>   		eth_random_addr(vdpasim->config.mac);
>   	}
>   
> -	vringh_set_iotlb(&vdpasim->vqs[0].vring, vdpasim->iommu);
> -	vringh_set_iotlb(&vdpasim->vqs[1].vring, vdpasim->iommu);
> +	for (i = 0; i < vdpasim->nvqs; i++)
> +		vringh_set_iotlb(&vdpasim->vqs[i].vring, vdpasim->iommu);
>   
>   	vdpasim->vdpa.dma_dev = dev;
>   	ret = vdpa_register_device(&vdpasim->vdpa);
> @@ -646,6 +653,7 @@ static void vdpasim_free(struct vdpa_device *vdpa)
>   	kfree(vdpasim->buffer);
>   	if (vdpasim->iommu)
>   		vhost_iotlb_free(vdpasim->iommu);
> +	kfree(vdpasim->vqs);
>   }
>   
>   static const struct vdpa_config_ops vdpasim_net_config_ops = {