[PATCH 2/5] iommu/amd: Drop unnecessary checks in amd_iommu_attach_device()

Nicolin Chen
2022-09-13T08:27:46Z

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 any more.

Suggested-by: Robin Murphy <robin.murphy@arm.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
drivers/iommu/amd/iommu.c | 12 ++----------
1 file changed, 2 insertions(+), 10 deletions(-)

diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c
index 828672a46a3d..930d9946b9f7 100644
--- a/drivers/iommu/amd/iommu.c
+++ b/drivers/iommu/amd/iommu.c
@@ -2135,21 +2135,13 @@ 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);

--
2.17.1