Re: [PATCH v3 08/19] iommufd: Add IOMMU_HWPT_SET_DIRTY

[Jason Gunthorpe <jgg@nvidia.com>]

On Sat, Sep 23, 2023 at 02:25:00AM +0100, Joao Martins wrote:
> diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
> index 32e259245314..22354b0ba554 100644
> --- a/drivers/iommu/iommufd/hw_pagetable.c
> +++ b/drivers/iommu/iommufd/hw_pagetable.c
> @@ -198,3 +198,24 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
>  	iommufd_put_object(&idev->obj);
>  	return rc;
>  }
> +
> +int iommufd_hwpt_set_dirty(struct iommufd_ucmd *ucmd)
> +{
> +	struct iommu_hwpt_set_dirty *cmd = ucmd->cmd;
> +	struct iommufd_hw_pagetable *hwpt;
> +	struct iommufd_ioas *ioas;
> +	int rc = -EOPNOTSUPP;

Default is never used?

> +	bool enable;
> +
> +	hwpt = iommufd_get_hwpt(ucmd, cmd->hwpt_id);
> +	if (IS_ERR(hwpt))
> +		return PTR_ERR(hwpt);
> +
> +	ioas = hwpt->ioas;
> +	enable = cmd->flags & IOMMU_DIRTY_TRACKING_ENABLED;

Check that incoming flags are not invalid

if (cmd->flags & ~IOMMU_DIRTY_TRACKING_ENABLED)
    return -EOPNOTSUPP

> diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
> index e71523cbd0de..ec0c34086af3 100644
> --- a/drivers/iommu/iommufd/main.c
> +++ b/drivers/iommu/iommufd/main.c
> @@ -315,6 +315,7 @@ union ucmd_buffer {
>  	struct iommu_ioas_unmap unmap;
>  	struct iommu_option option;
>  	struct iommu_vfio_ioas vfio_ioas;
> +	struct iommu_hwpt_set_dirty set_dirty;
>  #ifdef CONFIG_IOMMUFD_TEST
>  	struct iommu_test_cmd test;
>  #endif
> @@ -358,6 +359,8 @@ static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
>  		 val64),
>  	IOCTL_OP(IOMMU_VFIO_IOAS, iommufd_vfio_ioas, struct iommu_vfio_ioas,
>  		 __reserved),
> +	IOCTL_OP(IOMMU_HWPT_SET_DIRTY, iommufd_hwpt_set_dirty,
> +		 struct iommu_hwpt_set_dirty, __reserved),
>  #ifdef CONFIG_IOMMUFD_TEST
>  	IOCTL_OP(IOMMU_TEST_CMD, iommufd_test, struct iommu_test_cmd, last),
>  #endif

These two lists of things are sorted
> +
> +/*

/** ?

> + * enum iommufd_set_dirty_flags - Flags for steering dirty tracking
> + * @IOMMU_DIRTY_TRACKING_DISABLED: Disables dirty tracking
> + * @IOMMU_DIRTY_TRACKING_ENABLED: Enables dirty tracking
> + */
> +enum iommufd_hwpt_set_dirty_flags {
> +	IOMMU_DIRTY_TRACKING_DISABLED = 0,
> +	IOMMU_DIRTY_TRACKING_ENABLED = 1,
> +};

Probably get rid of disabled and call it _ENABLE so it is actualy a
flag

Jason