eventfd: only return events requested in poll_mask()

The ->poll_mask() operation has a mask of events that the caller
is interested in, but we're returning all events regardless.

Change to return only the events the caller is interested in. This
fixes aio IO_CMD_POLL returning immediately when called with POLLIN
on an eventfd, since an eventfd is almost always ready for a write.

Signed-off-by: Avi Kivity <avi@scylladb.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/fs/eventfd.c b/fs/eventfd.c
index 61c9514da5e956a36a90e9df601eccfc01b9595a..ceb1031f1cac948e74a970f02058cfeb52d7a351 100644 (file)
--- a/fs/eventfd.c
+++ b/fs/eventfd.c
@@ -156,11 +156,11 @@ static __poll_t eventfd_poll_mask(struct file *file, __poll_t eventmask)
        count = READ_ONCE(ctx->count);
 
        if (count > 0)
-               events |= EPOLLIN;
+               events |= (EPOLLIN & eventmask);
        if (count == ULLONG_MAX)
                events |= EPOLLERR;
        if (ULLONG_MAX - 1 > count)
-               events |= EPOLLOUT;
+               events |= (EPOLLOUT & eventmask);
 
        return events;
 }