2 * Function declerations and data structures related to the splice
5 * Copyright (C) 2007 Jens Axboe <jens.axboe@oracle.com>
11 #include <linux/pipe_fs_i.h>
14 * Flags passed in from splice/tee/vmsplice
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 */
24 * Passed to the actors
27 unsigned int len
, total_len
; /* current and remaining length */
28 unsigned int flags
; /* splice flags */
30 * actor() private data
33 void __user
*userptr
; /* memory to write to */
34 struct file
*file
; /* file to read/write */
35 void *data
; /* cookie */
37 loff_t pos
; /* file position */
38 loff_t
*opos
; /* sendfile: output position */
39 size_t num_spliced
; /* number of bytes already spliced */
40 bool need_wakeup
; /* need to wake up writer */
46 unsigned long private;
50 * Passed to splice_to_pipe
52 struct splice_pipe_desc
{
53 struct page
**pages
; /* page map */
54 struct partial_page
*partial
; /* pages[] may not be contig */
55 int nr_pages
; /* number of populated pages in map */
56 unsigned int nr_pages_max
; /* pages[] & partial[] arrays size */
57 unsigned int flags
; /* splice flags */
58 const struct pipe_buf_operations
*ops
;/* ops associated with output pipe */
59 void (*spd_release
)(struct splice_pipe_desc
*, unsigned int);
62 typedef int (splice_actor
)(struct pipe_inode_info
*, struct pipe_buffer
*,
63 struct splice_desc
*);
64 typedef int (splice_direct_actor
)(struct pipe_inode_info
*,
65 struct splice_desc
*);
67 extern ssize_t
splice_from_pipe(struct pipe_inode_info
*, struct file
*,
68 loff_t
*, size_t, unsigned int,
70 extern ssize_t
__splice_from_pipe(struct pipe_inode_info
*,
71 struct splice_desc
*, splice_actor
*);
72 extern int splice_from_pipe_feed(struct pipe_inode_info
*, struct splice_desc
*,
74 extern int splice_from_pipe_next(struct pipe_inode_info
*,
75 struct splice_desc
*);
76 extern void splice_from_pipe_begin(struct splice_desc
*);
77 extern void splice_from_pipe_end(struct pipe_inode_info
*,
78 struct splice_desc
*);
79 extern int pipe_to_file(struct pipe_inode_info
*, struct pipe_buffer
*,
80 struct splice_desc
*);
82 extern ssize_t
splice_to_pipe(struct pipe_inode_info
*,
83 struct splice_pipe_desc
*);
84 extern ssize_t
splice_direct_to_actor(struct file
*, struct splice_desc
*,
85 splice_direct_actor
*);
88 * for dynamic pipe sizing
90 extern int splice_grow_spd(const struct pipe_inode_info
*, struct splice_pipe_desc
*);
91 extern void splice_shrink_spd(struct splice_pipe_desc
*);
92 extern void spd_release_page(struct splice_pipe_desc
*, unsigned int);
94 extern const struct pipe_buf_operations page_cache_pipe_buf_ops
;