Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
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 struct io_rsrc_node *rsrc_node;
25};
26
27static int __io_splice_prep(struct io_kiocb *req,
28 const struct io_uring_sqe *sqe)
29{
30 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
31 unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
32
33 sp->len = READ_ONCE(sqe->len);
34 sp->flags = READ_ONCE(sqe->splice_flags);
35 if (unlikely(sp->flags & ~valid_flags))
36 return -EINVAL;
37 sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in);
38 sp->rsrc_node = NULL;
39 req->flags |= REQ_F_FORCE_ASYNC;
40 return 0;
41}
42
43int io_tee_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
44{
45 if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
46 return -EINVAL;
47 return __io_splice_prep(req, sqe);
48}
49
50void io_splice_cleanup(struct io_kiocb *req)
51{
52 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
53
54 io_put_rsrc_node(req->ctx, sp->rsrc_node);
55}
56
57static struct file *io_splice_get_file(struct io_kiocb *req,
58 unsigned int issue_flags)
59{
60 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
61 struct io_ring_ctx *ctx = req->ctx;
62 struct io_rsrc_node *node;
63 struct file *file = NULL;
64
65 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
66 return io_file_get_normal(req, sp->splice_fd_in);
67
68 io_ring_submit_lock(ctx, issue_flags);
69 node = io_rsrc_node_lookup(&ctx->file_table.data, sp->splice_fd_in);
70 if (node) {
71 node->refs++;
72 sp->rsrc_node = node;
73 file = io_slot_file(node);
74 req->flags |= REQ_F_NEED_CLEANUP;
75 }
76 io_ring_submit_unlock(ctx, issue_flags);
77 return file;
78}
79
80int io_tee(struct io_kiocb *req, unsigned int issue_flags)
81{
82 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
83 struct file *out = sp->file_out;
84 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
85 struct file *in;
86 ssize_t ret = 0;
87
88 WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
89
90 in = io_splice_get_file(req, issue_flags);
91 if (!in) {
92 ret = -EBADF;
93 goto done;
94 }
95
96 if (sp->len)
97 ret = do_tee(in, out, sp->len, flags);
98
99 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
100 fput(in);
101done:
102 if (ret != sp->len)
103 req_set_fail(req);
104 io_req_set_res(req, ret, 0);
105 return IOU_OK;
106}
107
108int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
109{
110 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
111
112 sp->off_in = READ_ONCE(sqe->splice_off_in);
113 sp->off_out = READ_ONCE(sqe->off);
114 return __io_splice_prep(req, sqe);
115}
116
117int io_splice(struct io_kiocb *req, unsigned int issue_flags)
118{
119 struct io_splice *sp = io_kiocb_to_cmd(req, struct io_splice);
120 struct file *out = sp->file_out;
121 unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
122 loff_t *poff_in, *poff_out;
123 struct file *in;
124 ssize_t ret = 0;
125
126 WARN_ON_ONCE(issue_flags & IO_URING_F_NONBLOCK);
127
128 in = io_splice_get_file(req, issue_flags);
129 if (!in) {
130 ret = -EBADF;
131 goto done;
132 }
133
134 poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
135 poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
136
137 if (sp->len)
138 ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
139
140 if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
141 fput(in);
142done:
143 if (ret != sp->len)
144 req_set_fail(req);
145 io_req_set_res(req, ret, 0);
146 return IOU_OK;
147}