linux-stable/io_uring/epoll.c
Stefan Metzmacher f2ccb5aed7 io_uring: make io_kiocb_to_cmd() typesafe
We need to make sure (at build time) that struct io_cmd_data is not
casted to a structure that's larger.

Signed-off-by: Stefan Metzmacher <metze@samba.org>
Link: https://lore.kernel.org/r/c024cdf25ae19fc0319d4180e2298bade8ed17b8.1660201408.git.metze@samba.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-08-12 17:01:00 -06:00

65 lines
1.5 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/uaccess.h>
#include <linux/io_uring.h>
#include <linux/eventpoll.h>
#include <uapi/linux/io_uring.h>
#include "io_uring.h"
#include "epoll.h"
#if defined(CONFIG_EPOLL)
struct io_epoll {
struct file *file;
int epfd;
int op;
int fd;
struct epoll_event event;
};
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);
pr_warn_once("%s: epoll_ctl support in io_uring is deprecated and will "
"be removed in a future Linux kernel version.\n",
current->comm);
if (sqe->buf_index || sqe->splice_fd_in)
return -EINVAL;
epoll->epfd = READ_ONCE(sqe->fd);
epoll->op = READ_ONCE(sqe->len);
epoll->fd = READ_ONCE(sqe->off);
if (ep_op_has_event(epoll->op)) {
struct epoll_event __user *ev;
ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
if (copy_from_user(&epoll->event, ev, sizeof(*ev)))
return -EFAULT;
}
return 0;
}
int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
{
struct io_epoll *ie = io_kiocb_to_cmd(req, struct io_epoll);
int ret;
bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
if (force_nonblock && ret == -EAGAIN)
return -EAGAIN;
if (ret < 0)
req_set_fail(req);
io_req_set_res(req, ret, 0);
return IOU_OK;
}
#endif