[PATCH v2] mm: Move MAP_SYNC to asm-generic/mman-common.h

From: Aneesh Kumar K.V
Date: Tue May 28 2019 - 05:15:31 EST


This enables support for synchronous DAX fault on powerpc

The generic changes are added as part of
commit b6fb293f2497 ("mm: Define MAP_SYNC and VM_SYNC flags")

Without this, mmap returns EOPNOTSUPP for MAP_SYNC with MAP_SHARED_VALIDATE

Instead of adding MAP_SYNC with same value to
arch/powerpc/include/uapi/asm/mman.h, I am moving the #define to
asm-generic/mman-common.h. Two architectures using mman-common.h directly are
sparc and powerpc. We should be able to consloidate more #defines to
mman-common.h. That can be done as a separate patch.

Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
---
Changes from V1:
* Move #define to mman-common.h instead of powerpc specific mman.h change


include/uapi/asm-generic/mman-common.h | 3 ++-
include/uapi/asm-generic/mman.h | 1 -
2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/uapi/asm-generic/mman-common.h b/include/uapi/asm-generic/mman-common.h
index abd238d0f7a4..bea0278f65ab 100644
--- a/include/uapi/asm-generic/mman-common.h
+++ b/include/uapi/asm-generic/mman-common.h
@@ -25,7 +25,8 @@
# define MAP_UNINITIALIZED 0x0 /* Don't support this flag */
#endif

-/* 0x0100 - 0x80000 flags are defined in asm-generic/mman.h */
+/* 0x0100 - 0x40000 flags are defined in asm-generic/mman.h */
+#define MAP_SYNC 0x080000 /* perform synchronous page faults for the mapping */
#define MAP_FIXED_NOREPLACE 0x100000 /* MAP_FIXED which doesn't unmap underlying mapping */

/*
diff --git a/include/uapi/asm-generic/mman.h b/include/uapi/asm-generic/mman.h
index 653687d9771b..2dffcbf705b3 100644
--- a/include/uapi/asm-generic/mman.h
+++ b/include/uapi/asm-generic/mman.h
@@ -13,7 +13,6 @@
#define MAP_NONBLOCK 0x10000 /* do not block on IO */
#define MAP_STACK 0x20000 /* give out an address that is best suited for process/thread stacks */
#define MAP_HUGETLB 0x40000 /* create a huge page mapping */
-#define MAP_SYNC 0x80000 /* perform synchronous page faults for the mapping */

/* Bits [26:31] are reserved, see mman-common.h for MAP_HUGETLB usage */

--
2.21.0