1 files changed, 21 insertions, 0 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h
index 7cfa5546c840..4a28deb5f210 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -2948,6 +2948,27 @@ static inline void mmdrop_async(struct mm_struct *mm)
 	}
 }
 
+/**
+ * mmget() - Pin the address space associated with a &struct mm_struct.
+ * @mm: The address space to pin.
+ *
+ * Make sure that the address space of the given &struct mm_struct doesn't
+ * go away. This does not protect against parts of the address space being
+ * modified or freed, however.
+ *
+ * Never use this function to pin this address space for an
+ * unbounded/indefinite amount of time.
+ *
+ * Use mmput() to release the reference acquired by mmget().
+ *
+ * See also <Documentation/vm/active_mm.txt> for an in-depth explanation
+ * of &mm_struct.mm_count vs &mm_struct.mm_users.
+ */
+static inline void mmget(struct mm_struct *mm)
+{
+	atomic_inc(&mm->mm_users);
+}
+
 static inline bool mmget_not_zero(struct mm_struct *mm)
 {
 	return atomic_inc_not_zero(&mm->mm_users);