[PATCH v2 05/13] iommufd: Add IOMMUFD_OBJ_EVENTQ_VIRQ and IOMMUFD_CMD_VIRQ_ALLOC

[Tian, Kevin]

> From: Nicolin Chen <nicolinc at nvidia.com>
> Sent: Wednesday, December 4, 2024 6:10 AM
> +
> +/* An iommufd_virq represents a vIOMMU interrupt in an eventq_virq
> queue */
> +struct iommufd_virq {
> +	struct iommufd_eventq_virq *eventq_virq;
> +	struct list_head node;
> +	ssize_t irq_len;
> +	void *irq_data;
> +};

looks the only use of eventq_virq is in below:

> +
> +static inline int iommufd_eventq_virq_handler(struct iommufd_virq *virq)
> +{
> +	return iommufd_eventq_notify(&virq->eventq_virq->common,
> &virq->node);
> +}

If there is no other intended usages upon that field, it's simpler to
remove it and directly pass the pointer in when the handler is 
called. Anyway iommufd_viommu_report_irq() needs to find the
eventq first before calling it.

> +/**
> + * struct iommu_virq_alloc - ioctl(IOMMU_VIRQ_ALLOC)
> + * @size: sizeof(struct iommu_virq_alloc)
> + * @flags: Must be 0
> + * @viommu: virtual IOMMU ID to associate the virtual IRQ with
> + * @type: Type of the virtual IRQ. Must be defined in enum
> iommu_virq_type
> + * @out_virq_id: The ID of the new virtual IRQ
> + * @out_fault_fd: The fd of the new virtual IRQ. User space must close the
> + *                successfully returned fd after using it

s/out_fault_fd/out_virq_fd/

> + *
> + * Explicitly allocate a virtual IRQ handler for a vIOMMU. A vIOMMU can
> have
> + * multiple FDs for different @type, but is confined to one FD per @type.
> + */

s/handler/interface/

> +
> +	eventq_virq->irq_wq = alloc_workqueue("viommu_irq/%d",
> WQ_UNBOUND, 0,
> +					      eventq_virq->common.obj.id);
> +	if (!eventq_virq->irq_wq) {
> +		rc = -ENOMEM;
> +		goto out_put_fdno;
> +	}

there is no use of this wq

> @@ -335,6 +335,8 @@ static const struct iommufd_ioctl_op
> iommufd_ioctl_ops[] = {
>  	IOCTL_OP(IOMMU_DESTROY, iommufd_destroy, struct
> iommu_destroy, id),
>  	IOCTL_OP(IOMMU_FAULT_QUEUE_ALLOC,
> iommufd_eventq_iopf_alloc,
>  		 struct iommu_fault_alloc, out_fault_fd),
> +	IOCTL_OP(IOMMU_VIRQ_ALLOC, iommufd_eventq_virq_alloc,
> +		 struct iommu_virq_alloc, out_virq_fd),

sort it in alphabetical order.