[PATCH 1/1] Revert "iommu/vt-d: Remove unused function"

[Lu Baolu <baolu.lu@linux.intel.com>]

This reverts commit c61c255e114c52682546447ed44d3470b5708134.

The pasid_set_wpe() helper, which was removed by the reverted commit,
is still used by the nesting translation support in the iommufd tree.
To avoid a merge conflict, revert the commit.

Link: https://lore.kernel.org/linux-kernel/20231025153455.283c5b12@canb.auug.org.au/
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
---
 drivers/iommu/intel/pasid.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index 06ddb3c927f5..8f92b92f3d2a 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c
@@ -335,6 +335,15 @@ static inline void pasid_set_fault_enable(struct pasid_entry *pe)
 	pasid_set_bits(&pe->val[0], 1 << 1, 0);
 }
 
+/*
+ * Setup the WPE(Write Protect Enable) field (Bit 132) of a
+ * scalable mode PASID entry.
+ */
+static inline void pasid_set_wpe(struct pasid_entry *pe)
+{
+	pasid_set_bits(&pe->val[2], 1 << 4, 1 << 4);
+}
+
 /*
  * Setup the P(Present) field (Bit 0) of a scalable mode PASID
  * entry.
-- 
2.34.1