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Diffstat (limited to 'include')
-rw-r--r--include/linux/intel-svm.h20
1 files changed, 20 insertions, 0 deletions
diff --git a/include/linux/intel-svm.h b/include/linux/intel-svm.h
index 3c25794042f9..99bc5b3ae26e 100644
--- a/include/linux/intel-svm.h
+++ b/include/linux/intel-svm.h
@@ -102,6 +102,21 @@ extern int intel_svm_bind_mm(struct device *dev, int *pasid, int flags,
*/
extern int intel_svm_unbind_mm(struct device *dev, int pasid);
+/**
+ * intel_svm_is_pasid_valid() - check if pasid is valid
+ * @dev: Device for which PASID was allocated
+ * @pasid: PASID value to be checked
+ *
+ * This function checks if the specified pasid is still valid. A
+ * valid pasid means the backing mm is still having a valid user.
+ * For kernel callers init_mm is always valid. for other mm, if mm->mm_users
+ * is non-zero, it is valid.
+ *
+ * returns -EINVAL if invalid pasid, 0 if pasid ref count is invalid
+ * 1 if pasid is valid.
+ */
+extern int intel_svm_is_pasid_valid(struct device *dev, int pasid);
+
#else /* CONFIG_INTEL_IOMMU_SVM */
static inline int intel_svm_bind_mm(struct device *dev, int *pasid,
@@ -114,6 +129,11 @@ static inline int intel_svm_unbind_mm(struct device *dev, int pasid)
{
BUG();
}
+
+static int intel_svm_is_pasid_valid(struct device *dev, int pasid)
+{
+ return -EINVAL;
+}
#endif /* CONFIG_INTEL_IOMMU_SVM */
#define intel_svm_available(dev) (!intel_svm_bind_mm((dev), NULL, 0, NULL))