io_uring/epoll.c

   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)
  16 struct io_epoll {
  17         struct file                     *file;
  18         int                             epfd;
  19         int                             op;
  20         int                             fd;
  21         struct epoll_event              event;
  22 };
  23
  24 int 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(epoll->op)) {
  36                 struct epoll_event __user *ev;
  37
  38                 ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
  39                 if (copy_from_user(&epoll->event, ev, sizeof(*ev)))
  40                         return -EFAULT;
  41         }
  42
  43         return 0;
  44 }
  45
  46 int 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(ie->epfd, ie->op, ie->fd, &ie->event, 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, ret, 0);
  59         return IOU_OK;
  60 }
  61 #endif