1// SPDX-License-Identifier: GPL-2.0
2#include <linux/kernel.h>
3#include <linux/errno.h>
4#include <linux/fs.h>
5#include <linux/file.h>
6#include <linux/io_uring.h>
7
8#include <uapi/linux/io_uring.h>
9
10#include "io_uring.h"
11#include "rsrc.h"
12#include "nop.h"
13
14struct io_nop {
15 /* NOTE: kiocb has the file as the first member, so don't do it here */
16 struct file *file;
17 int result;
18 int fd;
19 unsigned int flags;
20};
21
22#define NOP_FLAGS (IORING_NOP_INJECT_RESULT | IORING_NOP_FIXED_FILE | \
23 IORING_NOP_FIXED_BUFFER | IORING_NOP_FILE)
24
25int io_nop_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
26{
27 struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop);
28
29 nop->flags = READ_ONCE(sqe->nop_flags);
30 if (nop->flags & ~NOP_FLAGS)
31 return -EINVAL;
32
33 if (nop->flags & IORING_NOP_INJECT_RESULT)
34 nop->result = READ_ONCE(sqe->len);
35 else
36 nop->result = 0;
37 if (nop->flags & IORING_NOP_FILE)
38 nop->fd = READ_ONCE(sqe->fd);
39 else
40 nop->fd = -1;
41 if (nop->flags & IORING_NOP_FIXED_BUFFER)
42 req->buf_index = READ_ONCE(sqe->buf_index);
43 return 0;
44}
45
46int io_nop(struct io_kiocb *req, unsigned int issue_flags)
47{
48 struct io_nop *nop = io_kiocb_to_cmd(req, struct io_nop);
49 int ret = nop->result;
50
51 if (nop->flags & IORING_NOP_FILE) {
52 if (nop->flags & IORING_NOP_FIXED_FILE) {
53 req->file = io_file_get_fixed(req, fd: nop->fd, issue_flags);
54 req->flags |= REQ_F_FIXED_FILE;
55 } else {
56 req->file = io_file_get_normal(req, fd: nop->fd);
57 }
58 if (!req->file) {
59 ret = -EBADF;
60 goto done;
61 }
62 }
63 if (nop->flags & IORING_NOP_FIXED_BUFFER) {
64 if (!io_find_buf_node(req, issue_flags))
65 ret = -EFAULT;
66 }
67done:
68 if (ret < 0)
69 req_set_fail(req);
70 io_req_set_res(req, res: nop->result, cflags: 0);
71 return IOU_COMPLETE;
72}
73

source code of linux/io_uring/nop.c