aboutsummaryrefslogtreecommitdiff
path: root/io_uring/splice.c
blob: 53e4232d0866c7b01249d08a094ec89c8e871aef (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/fs.h>
#include <linux/file.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/namei.h>
#include <linux/io_uring.h>
#include <linux/splice.h>

#include <uapi/linux/io_uring.h>

#include "io_uring.h"
#include "splice.h"

struct io_splice {
	struct file			*file_out;
	loff_t				off_out;
	loff_t				off_in;
	u64				len;
	int				splice_fd_in;
	unsigned int			flags;
};

static int __io_splice_prep(struct io_kiocb *req,
			    const struct io_uring_sqe *sqe)
{
	struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
	unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;

	sp->len = READ_ONCE(sqe->len);
	sp->flags = READ_ONCE(sqe->splice_flags);
	if (unlikely(sp->flags & ~valid_flags))
		return -EINVAL;
	sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
	return 0;
}

int io_tee_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
	if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
		return -EINVAL;
	return __io_splice_prep(req, sqe);
}

int io_tee(struct io_kiocb *req, unsigned int issue_flags)
{
	struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
	struct file *out = sp->file_out;
	unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
	struct file *in;
	long ret = 0;

	if (issue_flags & IO_URING_F_NONBLOCK)
		return -EAGAIN;

	if (sp->flags & SPLICE_F_FD_IN_FIXED)
		in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
	else
		in = io_file_get_normal(req, sp->splice_fd_in);
	if (!in) {
		ret = -EBADF;
		goto done;
	}

	if (sp->len)
		ret = do_tee(in, out, sp->len, flags);

	if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
		io_put_file(in);
done:
	if (ret != sp->len)
		req_set_fail(req);
	io_req_set_res(req, ret, 0);
	return IOU_OK;
}

int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
{
	struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);

	sp->off_in = READ_ONCE(sqe->splice_off_in);
	sp->off_out = READ_ONCE(sqe->off);
	return __io_splice_prep(req, sqe);
}

int io_splice(struct io_kiocb *req, unsigned int issue_flags)
{
	struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
	struct file *out = sp->file_out;
	unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
	loff_t *poff_in, *poff_out;
	struct file *in;
	long ret = 0;

	if (issue_flags & IO_URING_F_NONBLOCK)
		return -EAGAIN;

	if (sp->flags & SPLICE_F_FD_IN_FIXED)
		in = io_file_get_fixed(req, sp->splice_fd_in, issue_flags);
	else
		in = io_file_get_normal(req, sp->splice_fd_in);
	if (!in) {
		ret = -EBADF;
		goto done;
	}

	poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
	poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;

	if (sp->len)
		ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);

	if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
		io_put_file(in);
done:
	if (ret != sp->len)
		req_set_fail(req);
	io_req_set_res(req, ret, 0);
	return IOU_OK;
}