[PATCH 2/2] iommufd/device: Drop enforce_cache_coherency in iommufd_hw_pagetable_attach

[Nicolin Chen]

According to the conversion in the following link:
https://lore.kernel.org/linux-iommu/20231020135501.GG3952@xxxxxxxxxx/

The enforce_cache_coherency should be set/enforced in the hwpt allocation
routine. The iommu driver in its attach_dev() op should decide whether to
reject or not a device that doesn't match with the configuration of cache
coherency. Drop the enforce_cache_coherency piece in attach(), so it will
be called only in the allocation routine. Then, drop it in the header and
mark it as a static function.

Cc: stable@xxxxxxxxxxxxxxx
Fixes: 17bad52708b4 ("iommufd: Add enforced_cache_coherency to iommufd_hw_pagetable_alloc()")
Suggested-by: Tian, Kevin <kevin.tian@xxxxxxxxx>
Signed-off-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
---
 drivers/iommu/iommufd/device.c          | 7 -------
 drivers/iommu/iommufd/hw_pagetable.c    | 2 +-
 drivers/iommu/iommufd/iommufd_private.h | 1 -
 3 files changed, 1 insertion(+), 9 deletions(-)

diff --git a/drivers/iommu/iommufd/device.c b/drivers/iommu/iommufd/device.c
index c93f3478f808..557c10fd4a7f 100644
--- a/drivers/iommu/iommufd/device.c
+++ b/drivers/iommu/iommufd/device.c
@@ -337,13 +337,6 @@ int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
 		goto err_unlock;
 	}
 
-	/* Try to upgrade the domain we have */
-	if (idev->enforce_cache_coherency) {
-		rc = iommufd_hw_pagetable_enforce_cc(hwpt);
-		if (rc)
-			goto err_unlock;
-	}
-
 	rc = iopt_table_enforce_dev_resv_regions(&hwpt->ioas->iopt, idev->dev,
 						 &idev->igroup->sw_msi_start);
 	if (rc)
diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index 8b3d2875d642..b8bad5b16b5f 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -42,7 +42,7 @@ void iommufd_hw_pagetable_abort(struct iommufd_object *obj)
 	iommufd_hw_pagetable_destroy(obj);
 }
 
-int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt)
+static int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt)
 {
 	if (hwpt->enforce_cache_coherency)
 		return 0;
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index 3064997a0181..60221e728e80 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -244,7 +244,6 @@ struct iommufd_hw_pagetable *
 iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
 			   struct iommufd_device *idev, u32 flags,
 			   bool immediate_attach);
-int iommufd_hw_pagetable_enforce_cc(struct iommufd_hw_pagetable *hwpt);
 int iommufd_hw_pagetable_attach(struct iommufd_hw_pagetable *hwpt,
 				struct iommufd_device *idev);
 struct iommufd_hw_pagetable *
-- 
2.42.0