[PATCH 3/5] iommu/vt-d: Remove SVM_FLAG_PRIVATE_PASID

From: Lu Baolu
Date: Mon Mar 22 2021 - 21:16:53 EST


The SVM_FLAG_PRIVATE_PASID has never been referenced in the tree, and
there's no plan to have anything to use it. So cleanup it.

Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
---
drivers/iommu/intel/svm.c | 40 ++++++++++++++++++---------------------
include/linux/intel-svm.h | 16 +++-------------
2 files changed, 21 insertions(+), 35 deletions(-)

diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c
index 875ee74d8c41..5165cea90421 100644
--- a/drivers/iommu/intel/svm.c
+++ b/drivers/iommu/intel/svm.c
@@ -465,9 +465,9 @@ intel_svm_bind_mm(struct device *dev, unsigned int flags,
struct mm_struct *mm, struct intel_svm_dev **sd)
{
struct intel_iommu *iommu = device_to_iommu(dev, NULL, NULL);
+ struct intel_svm *svm = NULL, *t;
struct device_domain_info *info;
struct intel_svm_dev *sdev;
- struct intel_svm *svm = NULL;
unsigned long iflags;
int pasid_max;
int ret;
@@ -493,30 +493,26 @@ intel_svm_bind_mm(struct device *dev, unsigned int flags,
}
}

- if (!(flags & SVM_FLAG_PRIVATE_PASID)) {
- struct intel_svm *t;
-
- list_for_each_entry(t, &global_svm_list, list) {
- if (t->mm != mm || (t->flags & SVM_FLAG_PRIVATE_PASID))
- continue;
-
- svm = t;
- if (svm->pasid >= pasid_max) {
- dev_warn(dev,
- "Limited PASID width. Cannot use existing PASID %d\n",
- svm->pasid);
- ret = -ENOSPC;
- goto out;
- }
+ list_for_each_entry(t, &global_svm_list, list) {
+ if (t->mm != mm)
+ continue;

- /* Find the matching device in svm list */
- for_each_svm_dev(sdev, svm, dev) {
- sdev->users++;
- goto success;
- }
+ svm = t;
+ if (svm->pasid >= pasid_max) {
+ dev_warn(dev,
+ "Limited PASID width. Cannot use existing PASID %d\n",
+ svm->pasid);
+ ret = -ENOSPC;
+ goto out;
+ }

- break;
+ /* Find the matching device in svm list */
+ for_each_svm_dev(sdev, svm, dev) {
+ sdev->users++;
+ goto success;
}
+
+ break;
}

sdev = kzalloc(sizeof(*sdev), GFP_KERNEL);
diff --git a/include/linux/intel-svm.h b/include/linux/intel-svm.h
index 6c9d10c0fb1e..10fa80eef13a 100644
--- a/include/linux/intel-svm.h
+++ b/include/linux/intel-svm.h
@@ -14,16 +14,6 @@
#define SVM_REQ_EXEC (1<<1)
#define SVM_REQ_PRIV (1<<0)

-/*
- * The SVM_FLAG_PRIVATE_PASID flag requests a PASID which is *not* the "main"
- * PASID for the current process. Even if a PASID already exists, a new one
- * will be allocated. And the PASID allocated with SVM_FLAG_PRIVATE_PASID
- * will not be given to subsequent callers. This facility allows a driver to
- * disambiguate between multiple device contexts which access the same MM,
- * if there is no other way to do so. It should be used sparingly, if at all.
- */
-#define SVM_FLAG_PRIVATE_PASID (1<<0)
-
/*
* The SVM_FLAG_SUPERVISOR_MODE flag requests a PASID which can be used only
* for access to kernel addresses. No IOTLB flushes are automatically done
@@ -35,18 +25,18 @@
* It is unlikely that we will ever hook into flush_tlb_kernel_range() to
* do such IOTLB flushes automatically.
*/
-#define SVM_FLAG_SUPERVISOR_MODE (1<<1)
+#define SVM_FLAG_SUPERVISOR_MODE BIT(0)
/*
* The SVM_FLAG_GUEST_MODE flag is used when a PASID bind is for guest
* processes. Compared to the host bind, the primary differences are:
* 1. mm life cycle management
* 2. fault reporting
*/
-#define SVM_FLAG_GUEST_MODE (1<<2)
+#define SVM_FLAG_GUEST_MODE BIT(1)
/*
* The SVM_FLAG_GUEST_PASID flag is used when a guest has its own PASID space,
* which requires guest and host PASID translation at both directions.
*/
-#define SVM_FLAG_GUEST_PASID (1<<3)
+#define SVM_FLAG_GUEST_PASID BIT(2)

#endif /* __INTEL_SVM_H__ */
--
2.25.1