[PATCH 5/5] iommu/vt-d: Remove hard coding PGSNP bit in PASID entries

From: Lu Baolu
Date: Sun May 01 2022 - 07:28:17 EST


As enforce_cache_coherency has been introduced into the iommu_domain_ops,
the kernel component which owns the iommu domain is able to opt-in its
requirement for force snooping support. The iommu driver has no need to
hard code the page snoop control bit in the PASID table entries anymore.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/pasid.h | 1 -
drivers/iommu/intel/iommu.c | 3 ---
drivers/iommu/intel/pasid.c | 6 ------
3 files changed, 10 deletions(-)

diff --git a/drivers/iommu/intel/pasid.h b/drivers/iommu/intel/pasid.h
index 583ea67fc783..394e6284ce1f 100644
--- a/drivers/iommu/intel/pasid.h
+++ b/drivers/iommu/intel/pasid.h
@@ -48,7 +48,6 @@
*/
#define PASID_FLAG_SUPERVISOR_MODE BIT(0)
#define PASID_FLAG_NESTED BIT(1)
-#define PASID_FLAG_PAGE_SNOOP BIT(2)

/*
* The PASID_FLAG_FL5LP flag Indicates using 5-level paging for first-
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index d5808495eb64..edd3d940eb25 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2432,9 +2432,6 @@ static int domain_setup_first_level(struct intel_iommu *iommu,
if (level == 5)
flags |= PASID_FLAG_FL5LP;

- if (domain->domain.type == IOMMU_DOMAIN_UNMANAGED)
- flags |= PASID_FLAG_PAGE_SNOOP;
-
return intel_pasid_setup_first_level(iommu, dev, (pgd_t *)pgd, pasid,
domain->iommu_did[iommu->seq_id],
flags);
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index 815c744e6a34..dc5020320323 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -625,9 +625,6 @@ int intel_pasid_setup_first_level(struct intel_iommu *iommu,
}
}

- if (flags & PASID_FLAG_PAGE_SNOOP)
- pasid_set_pgsnp(pte);
-
pasid_set_domain_id(pte, did);
pasid_set_address_width(pte, iommu->agaw);
pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));
@@ -710,9 +707,6 @@ int intel_pasid_setup_second_level(struct intel_iommu *iommu,
pasid_set_fault_enable(pte);
pasid_set_page_snoop(pte, !!ecap_smpwc(iommu->ecap));

- if (domain->domain.type == IOMMU_DOMAIN_UNMANAGED)
- pasid_set_pgsnp(pte);
-
/*
* Since it is a second level only translation setup, we should
* set SRE bit as well (addresses are expected to be GPAs).
--
2.25.1