[RFC PATCH 18/28] mm: add FAULT_FLAG_VMA_LOCK flag

[Suren Baghdasaryan <surenb@google.com>]

Add a new flag to distinguish page faults handled under protection of
per-vma lock.

Signed-off-by: Suren Baghdasaryan <surenb@google.com>
---
 include/linux/mm.h       | 3 ++-
 include/linux/mm_types.h | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index 0d9c1563c354..7c3190eaabd7 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -466,7 +466,8 @@ static inline bool fault_flag_allow_retry_first(enum fault_flag flags)
 	{ FAULT_FLAG_USER,		"USER" }, \
 	{ FAULT_FLAG_REMOTE,		"REMOTE" }, \
 	{ FAULT_FLAG_INSTRUCTION,	"INSTRUCTION" }, \
-	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }
+	{ FAULT_FLAG_INTERRUPTIBLE,	"INTERRUPTIBLE" }, \
+	{ FAULT_FLAG_VMA_LOCK,		"VMA_LOCK" }
 
 /*
  * vm_fault is filled by the pagefault handler and passed to the vma's
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 6a03f59c1e78..36562e702baf 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -886,6 +886,7 @@ enum fault_flag {
 	FAULT_FLAG_INTERRUPTIBLE =	1 << 9,
 	FAULT_FLAG_UNSHARE =		1 << 10,
 	FAULT_FLAG_ORIG_PTE_VALID =	1 << 11,
+	FAULT_FLAG_VMA_LOCK =		1 << 12,
 };
 
 typedef unsigned int __bitwise zap_flags_t;
-- 
2.37.2.672.g94769d06f0-goog