[PATCH v3] eventfd: add a uapi header for eventfd userspace APIs

[wenyang . linux]

From: Wen Yang <wenyang.linux@xxxxxxxxxxx>

Create a uapi header include/uapi/linux/eventfd.h, move the associated
flags to the uapi header, and include it from linux/eventfd.h.

Suggested-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Wen Yang <wenyang.linux@xxxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Dylan Yudaken <dylany@xxxxxx>
Cc: David Woodhouse <dwmw@xxxxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
v3: remove types.h that is not needed now
v2: improve the code based on Christian's suggestions

 include/linux/eventfd.h      |  6 +-----
 include/uapi/linux/eventfd.h | 11 +++++++++++
 2 files changed, 12 insertions(+), 5 deletions(-)
 create mode 100644 include/uapi/linux/eventfd.h

diff --git a/include/linux/eventfd.h b/include/linux/eventfd.h
index 98d31cdaca40..b9d83652c097 100644
--- a/include/linux/eventfd.h
+++ b/include/linux/eventfd.h
@@ -9,12 +9,12 @@
 #ifndef _LINUX_EVENTFD_H
 #define _LINUX_EVENTFD_H
 
-#include <linux/fcntl.h>
 #include <linux/wait.h>
 #include <linux/err.h>
 #include <linux/percpu-defs.h>
 #include <linux/percpu.h>
 #include <linux/sched.h>
+#include <uapi/linux/eventfd.h>
 
 /*
  * CAREFUL: Check include/uapi/asm-generic/fcntl.h when defining
@@ -23,10 +23,6 @@
  * from eventfd, in order to leave a free define-space for
  * shared O_* flags.
  */
-#define EFD_SEMAPHORE (1 << 0)
-#define EFD_CLOEXEC O_CLOEXEC
-#define EFD_NONBLOCK O_NONBLOCK
-
 #define EFD_SHARED_FCNTL_FLAGS (O_CLOEXEC | O_NONBLOCK)
 #define EFD_FLAGS_SET (EFD_SHARED_FCNTL_FLAGS | EFD_SEMAPHORE)
 
diff --git a/include/uapi/linux/eventfd.h b/include/uapi/linux/eventfd.h
new file mode 100644
index 000000000000..2eb9ab6c32f3
--- /dev/null
+++ b/include/uapi/linux/eventfd.h
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_LINUX_EVENTFD_H
+#define _UAPI_LINUX_EVENTFD_H
+
+#include <linux/fcntl.h>
+
+#define EFD_SEMAPHORE (1 << 0)
+#define EFD_CLOEXEC O_CLOEXEC
+#define EFD_NONBLOCK O_NONBLOCK
+
+#endif /* _UAPI_LINUX_EVENTFD_H */
-- 
2.25.1