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 struct io_epoll {
16 struct file *file;
17 int epfd;
18 int op;
19 int fd;
20 struct epoll_event event;
21 };
22
23 struct io_epoll_wait {
24 struct file *file;
25 int maxevents;
26 struct epoll_event __user *events;
27 };
28
io_epoll_ctl_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)29 int io_epoll_ctl_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
30 {
31 struct io_epoll *epoll = io_kiocb_to_cmd(req, struct io_epoll);
32
33 if (sqe->buf_index || sqe->splice_fd_in)
34 return -EINVAL;
35
36 epoll->epfd = READ_ONCE(sqe->fd);
37 epoll->op = READ_ONCE(sqe->len);
38 epoll->fd = READ_ONCE(sqe->off);
39
40 if (ep_op_has_event(epoll->op)) {
41 struct epoll_event __user *ev;
42
43 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
44 if (copy_from_user(&epoll->event, ev, sizeof(*ev)))
45 return -EFAULT;
46 }
47
48 return 0;
49 }
50
io_epoll_ctl(struct io_kiocb * req,unsigned int issue_flags)51 int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
52 {
53 struct io_epoll *ie = io_kiocb_to_cmd(req, struct io_epoll);
54 bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
55 struct epoll_key key;
56 int ret;
57
58 CLASS(fd, f)(ie->epfd);
59 if (fd_empty(f))
60 return -EBADF;
61
62 CLASS(fd, tf)(ie->fd);
63 if (fd_empty(tf))
64 return -EBADF;
65
66 key.file = fd_file(tf);
67 key.fd = ie->fd;
68 ret = do_epoll_ctl_file(fd_file(f), ie->op, &key, &ie->event, force_nonblock);
69 if (force_nonblock && ret == -EAGAIN)
70 return -EAGAIN;
71
72 if (ret < 0)
73 req_set_fail(req);
74 io_req_set_res(req, ret, 0);
75 return IOU_COMPLETE;
76 }
77
io_epoll_wait_prep(struct io_kiocb * req,const struct io_uring_sqe * sqe)78 int io_epoll_wait_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
79 {
80 struct io_epoll_wait *iew = io_kiocb_to_cmd(req, struct io_epoll_wait);
81
82 if (sqe->off || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
83 return -EINVAL;
84
85 iew->maxevents = READ_ONCE(sqe->len);
86 iew->events = u64_to_user_ptr(READ_ONCE(sqe->addr));
87 return 0;
88 }
89
io_epoll_wait(struct io_kiocb * req,unsigned int issue_flags)90 int io_epoll_wait(struct io_kiocb *req, unsigned int issue_flags)
91 {
92 struct io_epoll_wait *iew = io_kiocb_to_cmd(req, struct io_epoll_wait);
93 int ret;
94
95 ret = epoll_sendevents(req->file, iew->events, iew->maxevents);
96 if (ret == 0)
97 return -EAGAIN;
98 if (ret < 0)
99 req_set_fail(req);
100
101 io_req_set_res(req, ret, 0);
102 return IOU_COMPLETE;
103 }
104