[PATCH v3] epoll: drop EPOLLWAKEUP if PM_SLEEP is disabled

[Amit Pundir <amit.pundir@linaro.org>]

Drop EPOLLWAKEUP from epoll events mask if CONFIG_PM_SLEEP is disabled.

Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
---
Changes in v3:
 Renamed ep_epollwakeup_check() to ep_take_care_of_epollwakeup().
 Didn't update ep_create_wakeup_source() to return -ENOSYS if PM_SLEEP is unset.
---
 fs/eventpoll.c                 |    3 +--
 include/uapi/linux/eventpoll.h |   13 ++++++++++++-
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 473e09d..dbf382b 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -1820,8 +1820,7 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 		goto error_tgt_fput;
 
 	/* Check if EPOLLWAKEUP is allowed */
-	if ((epds.events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
-		epds.events &= ~EPOLLWAKEUP;
+	ep_take_care_of_epollwakeup(&epds);
 
 	/*
 	 * We have to check that the file structure underneath the file descriptor
diff --git a/include/uapi/linux/eventpoll.h b/include/uapi/linux/eventpoll.h
index 2c267bc..bc81fb2 100644
--- a/include/uapi/linux/eventpoll.h
+++ b/include/uapi/linux/eventpoll.h
@@ -61,5 +61,16 @@ struct epoll_event {
 	__u64 data;
 } EPOLL_PACKED;
 
-
+#ifdef CONFIG_PM_SLEEP
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	if ((epev->events & EPOLLWAKEUP) && !capable(CAP_BLOCK_SUSPEND))
+		epev->events &= ~EPOLLWAKEUP;
+}
+#else
+static inline void ep_take_care_of_epollwakeup(struct epoll_event *epev)
+{
+	epev->events &= ~EPOLLWAKEUP;
+}
+#endif
 #endif /* _UAPI_LINUX_EVENTPOLL_H */
-- 
1.7.10.4