iommu/amd: Drop unnecessary checks in amd_iommu_attach_device()

The same checks are done in amd_iommu_probe_device(). If any of them fails
there, then the device won't get a group, so there's no way for it to even
reach amd_iommu_attach_device anymore.

Link: https://lore.kernel.org/r/c054654a81f2b675c73108fe4bf10e45335a721a.1666042872.git.nicolinc@nvidia.com
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Reviewed-by: Vasant Hegde <vasant.hegde@amd.com>
Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index d3b39d0..45299eb 100644 (file)
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2155,21 +2155,13 @@ static void amd_iommu_detach_device(struct iommu_domain *dom,
 static int amd_iommu_attach_device(struct iommu_domain *dom,
                                   struct device *dev)
 {
+       struct iommu_dev_data *dev_data = dev_iommu_priv_get(dev);
        struct protection_domain *domain = to_pdomain(dom);
-       struct iommu_dev_data *dev_data;
-       struct amd_iommu *iommu;
+       struct amd_iommu *iommu = rlookup_amd_iommu(dev);
        int ret;
 
-       if (!check_device(dev))
-               return -EINVAL;
-
-       dev_data = dev_iommu_priv_get(dev);
        dev_data->defer_attach = false;
 
-       iommu = rlookup_amd_iommu(dev);
-       if (!iommu)
-               return -EINVAL;
-
        if (dev_data->domain)
                detach_device(dev);