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 size_t total_len
; /* remaining length */
28 unsigned int len
; /* current length */
29 unsigned int flags
; /* splice flags */
31 * actor() private data
34 void __user
*userptr
; /* memory to write to */
35 struct file
*file
; /* file to read/write */
36 void *data
; /* cookie */
38 loff_t pos
; /* file position */
39 loff_t
*opos
; /* sendfile: output position */
40 size_t num_spliced
; /* number of bytes already spliced */
41 bool need_wakeup
; /* need to wake up writer */
47 unsigned long private;
51 * Passed to splice_to_pipe
53 struct splice_pipe_desc
{
54 struct page
**pages
; /* page map */
55 struct partial_page
*partial
; /* pages[] may not be contig */
56 int nr_pages
; /* number of populated pages in map */
57 unsigned int nr_pages_max
; /* pages[] & partial[] arrays size */
58 unsigned int flags
; /* splice flags */
59 const struct pipe_buf_operations
*ops
;/* ops associated with output pipe */
60 void (*spd_release
)(struct splice_pipe_desc
*, unsigned int);
63 typedef int (splice_actor
)(struct pipe_inode_info
*, struct pipe_buffer
*,
64 struct splice_desc
*);
65 typedef int (splice_direct_actor
)(struct pipe_inode_info
*,
66 struct splice_desc
*);
68 extern ssize_t
splice_from_pipe(struct pipe_inode_info
*, struct file
*,
69 loff_t
*, size_t, unsigned int,
71 extern ssize_t
__splice_from_pipe(struct pipe_inode_info
*,
72 struct splice_desc
*, splice_actor
*);
73 extern ssize_t
splice_to_pipe(struct pipe_inode_info
*,
74 struct splice_pipe_desc
*);
75 extern ssize_t
add_to_pipe(struct pipe_inode_info
*,
76 struct pipe_buffer
*);
77 extern ssize_t
splice_direct_to_actor(struct file
*, struct splice_desc
*,
78 splice_direct_actor
*);
81 * for dynamic pipe sizing
83 extern int splice_grow_spd(const struct pipe_inode_info
*, struct splice_pipe_desc
*);
84 extern void splice_shrink_spd(struct splice_pipe_desc
*);
85 extern void spd_release_page(struct splice_pipe_desc
*, unsigned int);
87 extern const struct pipe_buf_operations page_cache_pipe_buf_ops
;
88 extern const struct pipe_buf_operations default_pipe_buf_ops
;