Merge branch 'for-6.15/io_uring-epoll-wait' into for-6.15/io_uring-reg-vec

* for-6.15/io_uring-epoll-wait:
  io_uring/epoll: add support for IORING_OP_EPOLL_WAIT
  io_uring/epoll: remove CONFIG_EPOLL guards
  eventpoll: add epoll_sendevents() helper
  eventpoll: abstract out ep_try_send_events() helper
  eventpoll: abstract out parameter sanity checking

1 files changed, 33 insertions, 2 deletions

diff --git a/io_uring/epoll.c b/io_uring/epoll.c
index 89bff2068a19..6d2c48ba1923 100644
--- a/io_uring/epoll.c
+++ b/io_uring/epoll.c
@@ -12,7 +12,6 @@
 #include "io_uring.h"
 #include "epoll.h"
 
-#if defined(CONFIG_EPOLL)
 struct io_epoll {
 	struct file			*file;
 	int				epfd;
@@ -21,6 +20,12 @@ struct io_epoll {
 	struct epoll_event		event;
 };
 
+struct io_epoll_wait {
+	struct file			*file;
+	int				maxevents;
+	struct epoll_event __user	*events;
+};
+
 int io_epoll_ctl_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_epoll *epoll = io_kiocb_to_cmd(req, struct io_epoll);
@@ -58,4 +63,30 @@ int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
 	io_req_set_res(req, ret, 0);
 	return IOU_OK;
 }
-#endif
+
+int io_epoll_wait_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	struct io_epoll_wait *iew = io_kiocb_to_cmd(req, struct io_epoll_wait);
+
+	if (sqe->off || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
+		return -EINVAL;
+
+	iew->maxevents = READ_ONCE(sqe->len);
+	iew->events = u64_to_user_ptr(READ_ONCE(sqe->addr));
+	return 0;
+}
+
+int io_epoll_wait(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_epoll_wait *iew = io_kiocb_to_cmd(req, struct io_epoll_wait);
+	int ret;
+
+	ret = epoll_sendevents(req->file, iew->events, iew->maxevents);
+	if (ret == 0)
+		return -EAGAIN;
+	if (ret < 0)
+		req_set_fail(req);
+
+	io_req_set_res(req, ret, 0);
+	return IOU_OK;
+}