The helper functions is not capable to modify the pasid entries which
are still in use. So should have a check against present bit.
Cc: Lu Baolu <baolu...@linux.intel.com>
Signed-off-by: Liu Yi L <yi.l....@intel.com>
---
drivers/iommu/intel/pasid.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index 02e10491184b..b1d0c2945c9a 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -534,6 +534,10 @@ void intel_pasid_tear_down_entry(struct intel_iommu
*iommu, struct device *dev,
devtlb_invalidation_with_pasid(iommu, dev, pasid);
}
+/*
+ * This function flushes cache for a newly setup pasid table entry.
+ * Caller of it should not modify the in-use pasid table entries.
+ */
static void pasid_flush_caches(struct intel_iommu *iommu,
struct pasid_entry *pte,
u32 pasid, u16 did)
@@ -585,6 +589,10 @@ int intel_pasid_setup_first_level(struct intel_iommu
*iommu,
if (WARN_ON(!pte))
return -EINVAL;
+ /* Caller must ensure PASID entry is not in use. */
+ if (pasid_pte_is_present(pte))
+ return -EBUSY;
+
pasid_clear_entry(pte);
/* Setup the first level page table pointer: */
@@ -684,6 +692,10 @@ int intel_pasid_setup_second_level(struct intel_iommu
*iommu,
return -ENODEV;
}
+ /* Caller must ensure PASID entry is not in use. */
+ if (pasid_pte_is_present(pte))
+ return -EBUSY;
+
pasid_clear_entry(pte);
pasid_set_domain_id(pte, did);
pasid_set_slptr(pte, pgd_val);
@@ -723,6 +735,10 @@ int intel_pasid_setup_pass_through(struct intel_iommu
*iommu,
return -ENODEV;
}
+ /* Caller must ensure PASID entry is not in use. */
+ if (pasid_pte_is_present(pte))
+ return -EBUSY;
+
pasid_clear_entry(pte);
pasid_set_domain_id(pte, did);
pasid_set_address_width(pte, iommu->agaw);
--
2.25.1
_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu
