Commit | Line | Data |
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d6b29d7c JA |
1 | /* |
2 | * Function declerations and data structures related to the splice | |
3 | * implementation. | |
4 | * | |
5 | * Copyright (C) 2007 Jens Axboe <jens.axboe@oracle.com> | |
6 | * | |
7 | */ | |
8 | #ifndef SPLICE_H | |
9 | #define SPLICE_H | |
10 | ||
11 | #include <linux/pipe_fs_i.h> | |
12 | ||
13 | /* | |
2b1ccc0e | 14 | * Flags passed in from splice/tee/vmsplice |
d6b29d7c JA |
15 | */ |
16 | #define SPLICE_F_MOVE (0x01) /* move pages instead of copying */ | |
17 | #define SPLICE_F_NONBLOCK (0x02) /* don't block on the pipe splicing (but */ | |
18 | /* we may still block on the fd we splice */ | |
19 | /* from/to, of course */ | |
20 | #define SPLICE_F_MORE (0x04) /* expect more data */ | |
21 | #define SPLICE_F_GIFT (0x08) /* pages passed in are a gift */ | |
22 | ||
23 | /* | |
24 | * Passed to the actors | |
25 | */ | |
26 | struct splice_desc { | |
27 | unsigned int len, total_len; /* current and remaining length */ | |
28 | unsigned int flags; /* splice flags */ | |
29 | /* | |
30 | * actor() private data | |
31 | */ | |
32 | union { | |
33 | void __user *userptr; /* memory to write to */ | |
34 | struct file *file; /* file to read/write */ | |
35 | void *data; /* cookie */ | |
36 | } u; | |
37 | loff_t pos; /* file position */ | |
b3c2d2dd MS |
38 | size_t num_spliced; /* number of bytes already spliced */ |
39 | bool need_wakeup; /* need to wake up writer */ | |
d6b29d7c JA |
40 | }; |
41 | ||
42 | struct partial_page { | |
43 | unsigned int offset; | |
44 | unsigned int len; | |
497f9625 | 45 | unsigned long private; |
d6b29d7c JA |
46 | }; |
47 | ||
48 | /* | |
49 | * Passed to splice_to_pipe | |
50 | */ | |
51 | struct splice_pipe_desc { | |
52 | struct page **pages; /* page map */ | |
53 | struct partial_page *partial; /* pages[] may not be contig */ | |
047fe360 ED |
54 | int nr_pages; /* number of populated pages in map */ |
55 | unsigned int nr_pages_max; /* pages[] & partial[] arrays size */ | |
d6b29d7c JA |
56 | unsigned int flags; /* splice flags */ |
57 | const struct pipe_buf_operations *ops;/* ops associated with output pipe */ | |
bbdfc2f7 | 58 | void (*spd_release)(struct splice_pipe_desc *, unsigned int); |
d6b29d7c JA |
59 | }; |
60 | ||
61 | typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *, | |
62 | struct splice_desc *); | |
63 | typedef int (splice_direct_actor)(struct pipe_inode_info *, | |
64 | struct splice_desc *); | |
65 | ||
66 | extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *, | |
67 | loff_t *, size_t, unsigned int, | |
68 | splice_actor *); | |
69 | extern ssize_t __splice_from_pipe(struct pipe_inode_info *, | |
70 | struct splice_desc *, splice_actor *); | |
b3c2d2dd MS |
71 | extern int splice_from_pipe_feed(struct pipe_inode_info *, struct splice_desc *, |
72 | splice_actor *); | |
73 | extern int splice_from_pipe_next(struct pipe_inode_info *, | |
74 | struct splice_desc *); | |
75 | extern void splice_from_pipe_begin(struct splice_desc *); | |
76 | extern void splice_from_pipe_end(struct pipe_inode_info *, | |
77 | struct splice_desc *); | |
328eaaba MS |
78 | extern int pipe_to_file(struct pipe_inode_info *, struct pipe_buffer *, |
79 | struct splice_desc *); | |
b3c2d2dd | 80 | |
d6b29d7c JA |
81 | extern ssize_t splice_to_pipe(struct pipe_inode_info *, |
82 | struct splice_pipe_desc *); | |
83 | extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *, | |
84 | splice_direct_actor *); | |
85 | ||
35f3d14d JA |
86 | /* |
87 | * for dynamic pipe sizing | |
88 | */ | |
047fe360 ED |
89 | extern int splice_grow_spd(const struct pipe_inode_info *, struct splice_pipe_desc *); |
90 | extern void splice_shrink_spd(struct splice_pipe_desc *); | |
708e3508 | 91 | extern void spd_release_page(struct splice_pipe_desc *, unsigned int); |
35f3d14d | 92 | |
708e3508 | 93 | extern const struct pipe_buf_operations page_cache_pipe_buf_ops; |
d6b29d7c | 94 | #endif |