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2#ifndef _LINUX_PIPE_FS_I_H
3#define _LINUX_PIPE_FS_I_H
4
5#define PIPE_DEF_BUFFERS 16
6
7#define PIPE_BUF_FLAG_LRU 0x01
8#define PIPE_BUF_FLAG_ATOMIC 0x02
9#define PIPE_BUF_FLAG_GIFT 0x04
10#define PIPE_BUF_FLAG_PACKET 0x08
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21struct pipe_buffer {
22 struct page *page;
23 unsigned int offset, len;
24 const struct pipe_buf_operations *ops;
25 unsigned int flags;
26 unsigned long private;
27};
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48struct pipe_inode_info {
49 struct mutex mutex;
50 wait_queue_head_t wait;
51 unsigned int nrbufs, curbuf, buffers;
52 unsigned int readers;
53 unsigned int writers;
54 unsigned int files;
55 unsigned int waiting_writers;
56 unsigned int r_counter;
57 unsigned int w_counter;
58 struct page *tmp_page;
59 struct fasync_struct *fasync_readers;
60 struct fasync_struct *fasync_writers;
61 struct pipe_buffer *bufs;
62 struct user_struct *user;
63};
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75struct pipe_buf_operations {
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83 int (*confirm)(struct pipe_inode_info *, struct pipe_buffer *);
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89 void (*release)(struct pipe_inode_info *, struct pipe_buffer *);
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99 int (*steal)(struct pipe_inode_info *, struct pipe_buffer *);
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104 bool (*get)(struct pipe_inode_info *, struct pipe_buffer *);
105};
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114static inline __must_check bool pipe_buf_get(struct pipe_inode_info *pipe,
115 struct pipe_buffer *buf)
116{
117 return buf->ops->get(pipe, buf);
118}
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125static inline void pipe_buf_release(struct pipe_inode_info *pipe,
126 struct pipe_buffer *buf)
127{
128 const struct pipe_buf_operations *ops = buf->ops;
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130 buf->ops = NULL;
131 ops->release(pipe, buf);
132}
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139static inline int pipe_buf_confirm(struct pipe_inode_info *pipe,
140 struct pipe_buffer *buf)
141{
142 return buf->ops->confirm(pipe, buf);
143}
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150static inline int pipe_buf_steal(struct pipe_inode_info *pipe,
151 struct pipe_buffer *buf)
152{
153 return buf->ops->steal(pipe, buf);
154}
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158#define PIPE_SIZE PAGE_SIZE
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161void pipe_lock(struct pipe_inode_info *);
162void pipe_unlock(struct pipe_inode_info *);
163void pipe_double_lock(struct pipe_inode_info *, struct pipe_inode_info *);
164
165extern unsigned int pipe_max_size;
166extern unsigned long pipe_user_pages_hard;
167extern unsigned long pipe_user_pages_soft;
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170void pipe_wait(struct pipe_inode_info *pipe);
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172struct pipe_inode_info *alloc_pipe_info(void);
173void free_pipe_info(struct pipe_inode_info *);
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176bool generic_pipe_buf_get(struct pipe_inode_info *, struct pipe_buffer *);
177int generic_pipe_buf_confirm(struct pipe_inode_info *, struct pipe_buffer *);
178int generic_pipe_buf_steal(struct pipe_inode_info *, struct pipe_buffer *);
179int generic_pipe_buf_nosteal(struct pipe_inode_info *, struct pipe_buffer *);
180void generic_pipe_buf_release(struct pipe_inode_info *, struct pipe_buffer *);
181void pipe_buf_mark_unmergeable(struct pipe_buffer *buf);
182
183extern const struct pipe_buf_operations nosteal_pipe_buf_ops;
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186long pipe_fcntl(struct file *, unsigned int, unsigned long arg);
187struct pipe_inode_info *get_pipe_info(struct file *file);
188
189int create_pipe_files(struct file **, int);
190unsigned int round_pipe_size(unsigned long size);
191
192#endif
193