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/mm.h>
7#include <linux/slab.h>
8#include <linux/namei.h>
9#include <linux/io_uring.h>
10#include <linux/splice.h>
11
12#include <uapi/linux/io_uring.h>
13
14#include "io_uring.h"
15#include "splice.h"
16
17struct io_splice {
18 struct file *file_out;
19 loff_t off_out;
20 loff_t off_in;
21 u64 len;
22 int splice_fd_in;
23 unsigned int flags;
24};
25
26static int __io_splice_prep(struct io_kiocb *req,
27 const struct io_uring_sqe *sqe)
28{
29 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
30 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
31
32 sp->len = READ_ONCE(sqe->len);
33 sp->flags = READ_ONCE(sqe->splice_flags);
34 if (unlikely(sp->flags & ~valid_flags))
35 return -EINVAL;
36 sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
37 req->flags |= REQ_F_FORCE_ASYNC;
38 return 0;
39}
40
41int io_tee_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
42{
43 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
44 return -EINVAL;
45 return __io_splice_prep(req, sqe);
46}
47
48int io_tee(struct io_kiocb *req, unsigned int issue_flags)
49{
50 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
51 struct file *out = sp->file_out;
52 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
53 struct file *in;
54 long ret = 0;
55
56 WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
57
58 if (sp->flags & SPLICE_F_FD_IN_FIXED)
59 in = io_file_get_fixed(req, fd: sp->splice_fd_in, issue_flags);
60 else
61 in = io_file_get_normal(req, fd: sp->splice_fd_in);
62 if (!in) {
63 ret = -EBADF;
64 goto done;
65 }
66
67 if (sp->len)
68 ret = do_tee(in, out, len: sp->len, flags);
69
70 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
71 fput(in);
72done:
73 if (ret != sp->len)
74 req_set_fail(req);
75 io_req_set_res(req, res: ret, cflags: 0);
76 return IOU_OK;
77}
78
79int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
80{
81 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
82
83 sp->off_in = READ_ONCE(sqe->splice_off_in);
84 sp->off_out = READ_ONCE(sqe->off);
85 return __io_splice_prep(req, sqe);
86}
87
88int io_splice(struct io_kiocb *req, unsigned int issue_flags)
89{
90 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
91 struct file *out = sp->file_out;
92 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
93 loff_t *poff_in, *poff_out;
94 struct file *in;
95 long ret = 0;
96
97 WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
98
99 if (sp->flags & SPLICE_F_FD_IN_FIXED)
100 in = io_file_get_fixed(req, fd: sp->splice_fd_in, issue_flags);
101 else
102 in = io_file_get_normal(req, fd: sp->splice_fd_in);
103 if (!in) {
104 ret = -EBADF;
105 goto done;
106 }
107
108 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
109 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
110
111 if (sp->len)
112 ret = do_splice(in, off_in: poff_in, out, off_out: poff_out, len: sp->len, flags);
113
114 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
115 fput(in);
116done:
117 if (ret != sp->len)
118 req_set_fail(req);
119 io_req_set_res(req, res: ret, cflags: 0);
120 return IOU_OK;
121}
122

source code of linux/io_uring/splice.c