linux-stable/io_uring/epoll.c
Jens Axboe 61a2732af4 io_uring: deprecate epoll_ctl support
As far as we know, nobody ever adopted the epoll_ctl management via
io_uring. Deprecate it now with a warning, and plan on removing it in
a later kernel version. When we do remove it, we can revert the following
commits as well:

39220e8d4a ("eventpoll: support non-blocking do_epoll_ctl() calls")
58e41a44c4 ("eventpoll: abstract out epoll_ctl() handler")

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/io-uring/CAHk-=wiTyisXBgKnVHAGYCNvkmjk=50agS2Uk6nr+n3ssLZg2w@mail.gmail.com/
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2022-07-24 18:39:12 -06:00

66 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_types.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);
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);
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