kernel-aes67/include/linux/pipe_fs_i.h
Linus Torvalds 1da177e4c3 Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!
2005-04-16 15:20:36 -07:00

60 lines
1.9 KiB
C

#ifndef _LINUX_PIPE_FS_I_H
#define _LINUX_PIPE_FS_I_H
#define PIPEFS_MAGIC 0x50495045
#define PIPE_BUFFERS (16)
struct pipe_buffer {
struct page *page;
unsigned int offset, len;
struct pipe_buf_operations *ops;
};
struct pipe_buf_operations {
int can_merge;
void * (*map)(struct file *, struct pipe_inode_info *, struct pipe_buffer *);
void (*unmap)(struct pipe_inode_info *, struct pipe_buffer *);
void (*release)(struct pipe_inode_info *, struct pipe_buffer *);
};
struct pipe_inode_info {
wait_queue_head_t wait;
unsigned int nrbufs, curbuf;
struct pipe_buffer bufs[PIPE_BUFFERS];
struct page *tmp_page;
unsigned int start;
unsigned int readers;
unsigned int writers;
unsigned int waiting_writers;
unsigned int r_counter;
unsigned int w_counter;
struct fasync_struct *fasync_readers;
struct fasync_struct *fasync_writers;
};
/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
#define PIPE_SIZE PAGE_SIZE
#define PIPE_SEM(inode) (&(inode).i_sem)
#define PIPE_WAIT(inode) (&(inode).i_pipe->wait)
#define PIPE_BASE(inode) ((inode).i_pipe->base)
#define PIPE_START(inode) ((inode).i_pipe->start)
#define PIPE_LEN(inode) ((inode).i_pipe->len)
#define PIPE_READERS(inode) ((inode).i_pipe->readers)
#define PIPE_WRITERS(inode) ((inode).i_pipe->writers)
#define PIPE_WAITING_WRITERS(inode) ((inode).i_pipe->waiting_writers)
#define PIPE_RCOUNTER(inode) ((inode).i_pipe->r_counter)
#define PIPE_WCOUNTER(inode) ((inode).i_pipe->w_counter)
#define PIPE_FASYNC_READERS(inode) (&((inode).i_pipe->fasync_readers))
#define PIPE_FASYNC_WRITERS(inode) (&((inode).i_pipe->fasync_writers))
/* Drop the inode semaphore and wait for a pipe event, atomically */
void pipe_wait(struct inode * inode);
struct inode* pipe_new(struct inode* inode);
void free_pipe_info(struct inode* inode);
#endif