2 files changed, 16 insertions, 1 deletions
diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h
index 1149533aa2fa..9806184bb3d5 100644
--- a/include/linux/sched/mm.h
+++ b/include/linux/sched/mm.h
@@ -36,7 +36,18 @@ static inline void mmgrab(struct mm_struct *mm)
 	atomic_inc(&mm->mm_count);
 }
 
-extern void mmdrop(struct mm_struct *mm);
+extern void __mmdrop(struct mm_struct *mm);
+
+static inline void mmdrop(struct mm_struct *mm)
+{
+	/*
+	 * The implicit full barrier implied by atomic_dec_and_test() is
+	 * required by the membarrier system call before returning to
+	 * user-space, after storing to rq->curr.
+	 */
+	if (unlikely(atomic_dec_and_test(&mm->mm_count)))
+		__mmdrop(mm);
+}
 
 /**
  * mmget() - Pin the address space associated with a &struct mm_struct.
diff --git a/include/linux/sched/user.h b/include/linux/sched/user.h
index 0dcf4e480ef7..96fe289c4c6e 100644
--- a/include/linux/sched/user.h
+++ b/include/linux/sched/user.h
@@ -4,6 +4,7 @@
 
 #include <linux/uidgid.h>
 #include <linux/atomic.h>
+#include <linux/ratelimit.h>
 
 struct key;
 
@@ -41,6 +42,9 @@ struct user_struct {
     defined(CONFIG_NET)
 	atomic_long_t locked_vm;
 #endif
+
+	/* Miscellaneous per-user rate limit */
+	struct ratelimit_state ratelimit;
 };
 
 extern int uids_sysfs_init(void);