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#ifndef _LINUX_PIPE_FS_I_H
#define _LINUX_PIPE_FS_I_H

#define PIPEFS_MAGIC 0x50495045
struct pipe_inode_info {
        wait_queue_head_t wait;
        char *base;
        unsigned int len;
        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))

#define PIPE_EMPTY(inode)       (PIPE_LEN(inode) == 0)
#define PIPE_FULL(inode)        (PIPE_LEN(inode) == PIPE_SIZE)
#define PIPE_FREE(inode)        (PIPE_SIZE - PIPE_LEN(inode))
#define PIPE_END(inode) ((PIPE_START(inode) + PIPE_LEN(inode)) & (PIPE_SIZE-1))
#define PIPE_MAX_RCHUNK(inode)  (PIPE_SIZE - PIPE_START(inode))
#define PIPE_MAX_WCHUNK(inode)  (PIPE_SIZE - PIPE_END(inode))

/* Drop the inode semaphore and wait for a pipe event, atomically */
void pipe_wait(struct inode * inode);

struct inode* pipe_new(struct inode* inode);

#endif