[RFC PATCH 1/6] iommu: Add two pasid helper functions

[Tina Zhang <tina.zhang@intel.com>]

mm_get_pasid() is for getting mm pasid value and mm_set_pasid() is for
setting mm pasid value.

The motivation is to replace mm->pasid with an iommu private data
structure that is introduced in a later patch.

Signed-off-by: Tina Zhang <tina.zhang@intel.com>
---
 arch/x86/kernel/traps.c |  2 +-
 include/linux/iommu.h   | 14 ++++++++++++++
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 58b1f208eff51..8587461c43664 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -678,7 +678,7 @@ static bool try_fixup_enqcmd_gp(void)
 	if (!mm_valid_pasid(current->mm))
 		return false;
 
-	pasid = current->mm->pasid;
+	pasid = mm_get_pasid(current->mm);
 
 	/*
 	 * Did this thread already have its PASID activated?
diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index e8c9a7da10609..d39e647219eb8 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -1174,6 +1174,15 @@ static inline bool mm_valid_pasid(struct mm_struct *mm)
 {
 	return mm->pasid != IOMMU_PASID_INVALID;
 }
+static inline u32 mm_get_pasid(struct mm_struct *mm)
+{
+	return mm->pasid;
+}
+
+static inline void mm_set_pasid(struct mm_struct *mm, u32 pasid)
+{
+	mm->pasid = pasid;
+}
 void mm_pasid_drop(struct mm_struct *mm);
 struct iommu_sva *iommu_sva_bind_device(struct device *dev,
 					struct mm_struct *mm);
@@ -1196,6 +1205,11 @@ static inline u32 iommu_sva_get_pasid(struct iommu_sva *handle)
 }
 static inline void mm_pasid_init(struct mm_struct *mm) {}
 static inline bool mm_valid_pasid(struct mm_struct *mm) { return false; }
+static inline u32 mm_get_pasid(struct mm_struct *mm)
+{
+	return IOMMU_PASID_INVALID;
+}
+static inline void mm_set_pasid(struct mm_struct *mm, u32 pasid) {}
 static inline void mm_pasid_drop(struct mm_struct *mm) {}
 #endif /* CONFIG_IOMMU_SVA */
 
-- 
2.34.1