[PATCH v3 15/15] iommu: Clean up bus_set_iommu()

[Matthew Rosato]

On 7/5/22 1:08 PM, Robin Murphy wrote:
> Clean up the remaining trivial bus_set_iommu() callsites along
> with the implementation. Now drivers only have to know and care
> about iommu_device instances, phew!
> 
> Signed-off-by: Robin Murphy <robin.murphy at arm.com>
> ---
> 
> v3: Also catch Intel's cheeky open-coded assignment
> 

...

> diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c
> index c898bcbbce11..dd957145fb81 100644
> --- a/drivers/iommu/s390-iommu.c
> +++ b/drivers/iommu/s390-iommu.c
> @@ -385,9 +385,3 @@ static const struct iommu_ops s390_iommu_ops = {
>   		.free		= s390_domain_free,
>   	}
>   };
> -
> -static int __init s390_iommu_init(void)
> -{
> -	return bus_set_iommu(&pci_bus_type, &s390_iommu_ops);
> -}
> -subsys_initcall(s390_iommu_init);

Previously s390_iommu_ops was only being set for pci_bus_type, but with 
this series it will now also be set for platform_bus_type.

To tolerate that, this series needs a change along the lines of:


From: Matthew Rosato <mjrosato at linux.ibm.com> 

Date: Thu, 7 Jul 2022 08:45:44 -0400 

Subject: [PATCH] iommu/s390: fail probe for non-pci device 

 

s390-iommu only supports pci_bus_type today 

 

Signed-off-by: Matthew Rosato <mjrosato at linux.ibm.com> 

--- 

  drivers/iommu/s390-iommu.c | 7 ++++++- 

  1 file changed, 6 insertions(+), 1 deletion(-) 

 

diff --git a/drivers/iommu/s390-iommu.c b/drivers/iommu/s390-iommu.c 

index dd957145fb81..762f892b4ec3 100644 

--- a/drivers/iommu/s390-iommu.c 

+++ b/drivers/iommu/s390-iommu.c 

@@ -185,7 +185,12 @@ static void s390_iommu_detach_device(struct 
iommu_domain *domain,
 

  static struct iommu_device *s390_iommu_probe_device(struct device 
*dev)
  { 

-       struct zpci_dev *zdev = to_zpci_dev(dev); 

+       struct zpci_dev *zdev; 

+ 

+       if (!dev_is_pci(dev)) 

+               return ERR_PTR(-ENODEV); 

+ 

+       zdev = to_zpci_dev(dev); 

 

         return &zdev->iommu_dev; 

  }  return &zdev->iommu_dev; 

  }