[PATCH 1/5] iommu: Add mm_get_pasid() helper function

From: Tina Zhang
Date: Tue Aug 08 2023 - 12:42:56 EST


mm_get_pasid() is for getting 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@xxxxxxxxx>
---
arch/x86/kernel/traps.c | 2 +-
include/linux/iommu.h | 8 ++++++++
2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 4a817d20ce3b..6e259b11cd87 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 d31642596675..30e4d1ca39b5 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -1180,6 +1180,10 @@ 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;
+}
void mm_pasid_drop(struct mm_struct *mm);
struct iommu_sva *iommu_sva_bind_device(struct device *dev,
struct mm_struct *mm);
@@ -1202,6 +1206,10 @@ 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_pasid_drop(struct mm_struct *mm) {}
#endif /* CONFIG_IOMMU_SVA */

--
2.17.1