This change wraps the existing mmap_sem related rwsem calls into a new
MM locking API. This is in preparation to extending that API to support
locking fine grained memory ranges.
Signed-off-by: Michel Lespinasse <walken@xxxxxxxxxx>
---
include/linux/mm.h | 1 +
include/linux/mm_lock.h | 59 +++++++++++++++++++++++++++++++++++++++++
2 files changed, 60 insertions(+)
create mode 100644 include/linux/mm_lock.h
diff --git include/linux/mm.h include/linux/mm.h
index cfaa8feecfe8..052f423d7f67 100644
--- include/linux/mm.h
+++ include/linux/mm.h
@@ -15,6 +15,7 @@
#include <linux/atomic.h>
#include <linux/debug_locks.h>
#include <linux/mm_types.h>
+#include <linux/mm_lock.h>
#include <linux/range.h>
#include <linux/pfn.h>
#include <linux/percpu-refcount.h>
diff --git include/linux/mm_lock.h include/linux/mm_lock.h
new file mode 100644
index 000000000000..b5f134285e53
--- /dev/null
+++ include/linux/mm_lock.h
@@ -0,0 +1,59 @@
+#ifndef _LINUX_MM_LOCK_H
+#define _LINUX_MM_LOCK_H
+
+static inline void mm_init_lock(struct mm_struct *mm)
+{
+ init_rwsem(&mm->mmap_sem);
+}
+
+static inline void mm_write_lock(struct mm_struct *mm)
+{
+ down_write(&mm->mmap_sem);
+}
+
+static inline int mm_write_lock_killable(struct mm_struct *mm)
+{
+ return down_write_killable(&mm->mmap_sem);
+}
+
+static inline bool mm_write_trylock(struct mm_struct *mm)
+{
+ return down_write_trylock(&mm->mmap_sem) != 0;
+}
+
+static inline void mm_write_unlock(struct mm_struct *mm)
+{
+ up_write(&mm->mmap_sem);
+}
+
+static inline void mm_downgrade_write_lock(struct mm_struct *mm)
+{
+ downgrade_write(&mm->mmap_sem);
+}
+
+static inline void mm_read_lock(struct mm_struct *mm)
+{
+ down_read(&mm->mmap_sem);
+}
+
+static inline int mm_read_lock_killable(struct mm_struct *mm)
+{
+ return down_read_killable(&mm->mmap_sem);
+}
+
+static inline bool mm_read_trylock(struct mm_struct *mm)
+{
+ return down_read_trylock(&mm->mmap_sem) != 0;
+}
+
+static inline void mm_read_unlock(struct mm_struct *mm)
+{
+ up_read(&mm->mmap_sem);
+}
+
+static inline bool mm_is_locked(struct mm_struct *mm)
+{
+ return rwsem_is_locked(&mm->mmap_sem) != 0;
+}
+
+#endif /* _LINUX_MM_LOCK_H */
--
2.25.0.341.g760bfbb309-goog
