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

Matthew Rosato
2022-07-07T12:50:34Z

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@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@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@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;

}