Re: [PATCH 1/7] iommu/ipmmu-vmsa: Link IOMMUs and devices in sysfs

[Laurent Pinchart]

Hi Geert,

Thank you for the patch.

On Wed, Feb 20, 2019 at 04:05:25PM +0100, Geert Uytterhoeven wrote:
> As of commit 7af9a5fdb9e0ca33 ("iommu/ipmmu-vmsa: Use
> iommu_device_sysfs_add()/remove()"), IOMMU devices show up under
> /sys/class/iommus/, but their "devices" subdirectories are empty.
> Likewise, devices tied to an IOMMU do not have an "iommu" backlink.
> 
> Make sure all links are created, on both arm32 and arm64.
> 
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

Reviewed-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>

> ---
>  drivers/iommu/ipmmu-vmsa.c | 24 +++++++++++++++++-------
>  1 file changed, 17 insertions(+), 7 deletions(-)
> 
> diff --git a/drivers/iommu/ipmmu-vmsa.c b/drivers/iommu/ipmmu-vmsa.c
> index 9a380c10655e182d..9f2b781e20a0eba6 100644
> --- a/drivers/iommu/ipmmu-vmsa.c
> +++ b/drivers/iommu/ipmmu-vmsa.c
> @@ -885,27 +885,37 @@ static int ipmmu_init_arm_mapping(struct device *dev)
>  
>  static int ipmmu_add_device(struct device *dev)
>  {
> +	struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
>  	struct iommu_group *group;
> +	int ret;
>  
>  	/*
>  	 * Only let through devices that have been verified in xlate()
>  	 */
> -	if (!to_ipmmu(dev))
> +	if (!mmu)
>  		return -ENODEV;
>  
> -	if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA))
> -		return ipmmu_init_arm_mapping(dev);
> +	if (IS_ENABLED(CONFIG_ARM) && !IS_ENABLED(CONFIG_IOMMU_DMA)) {
> +		ret = ipmmu_init_arm_mapping(dev);
> +		if (ret)
> +			return ret;
> +	} else {
> +		group = iommu_group_get_for_dev(dev);
> +		if (IS_ERR(group))
> +			return PTR_ERR(group);
>  
> -	group = iommu_group_get_for_dev(dev);
> -	if (IS_ERR(group))
> -		return PTR_ERR(group);
> +		iommu_group_put(group);
> +	}
>  
> -	iommu_group_put(group);
> +	iommu_device_link(&mmu->iommu, dev);
>  	return 0;
>  }
>  
>  static void ipmmu_remove_device(struct device *dev)
>  {
> +	struct ipmmu_vmsa_device *mmu = to_ipmmu(dev);
> +
> +	iommu_device_unlink(&mmu->iommu, dev);
>  	arm_iommu_detach_device(dev);
>  	iommu_group_remove_device(dev);
>  }

-- 
Regards,

Laurent Pinchart