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
|
/* SPDX-License-Identifier: GPL-2.0 */
/*
* Function declerations and data structures related to the splice
* implementation.
*
* Copyright (C) 2007 Jens Axboe <jens.axboe@oracle.com>
*
*/
#ifndef SPLICE_H
#define SPLICE_H
#include <linux/pipe_fs_i.h>
/*
* Flags passed in from splice/tee/vmsplice
*/
#define SPLICE_F_MOVE (0x01) /* move pages instead of copying */
#define SPLICE_F_NONBLOCK (0x02) /* don't block on the pipe splicing (but */
/* we may still block on the fd we splice */
/* from/to, of course */
#define SPLICE_F_MORE (0x04) /* expect more data */
#define SPLICE_F_GIFT (0x08) /* pages passed in are a gift */
#define SPLICE_F_ALL (SPLICE_F_MOVE|SPLICE_F_NONBLOCK|SPLICE_F_MORE|SPLICE_F_GIFT)
/*
* Passed to the actors
*/
struct splice_desc {
size_t total_len; /* remaining length */
unsigned int len; /* current length */
unsigned int flags; /* splice flags */
/*
* actor() private data
*/
union {
void __user *userptr; /* memory to write to */
struct file *file; /* file to read/write */
void *data; /* cookie */
} u;
void (*splice_eof)(struct splice_desc *sd); /* Unexpected EOF handler */
loff_t pos; /* file position */
loff_t *opos; /* sendfile: output position */
size_t num_spliced; /* number of bytes already spliced */
bool need_wakeup; /* need to wake up writer */
};
struct partial_page {
unsigned int offset;
unsigned int len;
unsigned long private;
};
/*
* Passed to splice_to_pipe
*/
struct splice_pipe_desc {
struct page **pages; /* page map */
struct partial_page *partial; /* pages[] may not be contig */
int nr_pages; /* number of populated pages in map */
unsigned int nr_pages_max; /* pages[] & partial[] arrays size */
const struct pipe_buf_operations *ops;/* ops associated with output pipe */
void (*spd_release)(struct splice_pipe_desc *, unsigned int);
};
typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
struct splice_desc *);
typedef int (splice_direct_actor)(struct pipe_inode_info *,
struct splice_desc *);
extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *,
loff_t *, size_t, unsigned int,
splice_actor *);
extern ssize_t __splice_from_pipe(struct pipe_inode_info *,
struct splice_desc *, splice_actor *);
extern ssize_t splice_to_pipe(struct pipe_inode_info *,
struct splice_pipe_desc *);
extern ssize_t add_to_pipe(struct pipe_inode_info *,
struct pipe_buffer *);
long vfs_splice_read(struct file *in, loff_t *ppos,
struct pipe_inode_info *pipe, size_t len,
unsigned int flags);
ssize_t splice_direct_to_actor(struct file *file, struct splice_desc *sd,
splice_direct_actor *actor);
long do_splice(struct file *in, loff_t *off_in, struct file *out,
loff_t *off_out, size_t len, unsigned int flags);
long do_splice_direct(struct file *in, loff_t *ppos, struct file *out,
loff_t *opos, size_t len, unsigned int flags);
long splice_file_range(struct file *in, loff_t *ppos, struct file *out,
loff_t *opos, size_t len);
extern long do_tee(struct file *in, struct file *out, size_t len,
unsigned int flags);
extern ssize_t splice_to_socket(struct pipe_inode_info *pipe, struct file *out,
loff_t *ppos, size_t len, unsigned int flags);
/*
* for dynamic pipe sizing
*/
extern int splice_grow_spd(const struct pipe_inode_info *, struct splice_pipe_desc *);
extern void splice_shrink_spd(struct splice_pipe_desc *);
extern const struct pipe_buf_operations page_cache_pipe_buf_ops;
extern const struct pipe_buf_operations default_pipe_buf_ops;
#endif
|
