1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kernel.h>
3#include <linux/errno.h>
4#include <linux/file.h>
5#include <linux/fs.h>
6#include <linux/uaccess.h>
7#include <linux/io_uring.h>
8#include <linux/eventpoll.h>
9
10#include <uapi/linux/io_uring.h>
11
12#include "io_uring.h"
13#include "epoll.h"
14
15#if defined(CONFIG_EPOLL)
16struct io_epoll {
17 struct file *file;
18 int epfd;
19 int op;
20 int fd;
21 struct epoll_event event;
22};
23
24int io_epoll_ctl_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
25{
26 struct io_epoll *epoll = io_kiocb_to_cmd(req, struct io_epoll);
27
28 if (sqe->buf_index || sqe->splice_fd_in)
29 return -EINVAL;
30
31 epoll->epfd = READ_ONCE(sqe->fd);
32 epoll->op = READ_ONCE(sqe->len);
33 epoll->fd = READ_ONCE(sqe->off);
34
35 if (ep_op_has_event(op: epoll->op)) {
36 struct epoll_event __user *ev;
37
38 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
39 if (copy_from_user(to: &epoll->event, from: ev, n: sizeof(*ev)))
40 return -EFAULT;
41 }
42
43 return 0;
44}
45
46int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
47{
48 struct io_epoll *ie = io_kiocb_to_cmd(req, struct io_epoll);
49 int ret;
50 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
51
52 ret = do_epoll_ctl(epfd: ie->epfd, op: ie->op, fd: ie->fd, epds: &ie->event, nonblock: force_nonblock);
53 if (force_nonblock && ret == -EAGAIN)
54 return -EAGAIN;
55
56 if (ret < 0)
57 req_set_fail(req);
58 io_req_set_res(req, res: ret, cflags: 0);
59 return IOU_OK;
60}
61#endif
62

source code of linux/io_uring/epoll.c