[net-next-2.6.git] / include / linux / pipe_fs_i.h

#ifndef _LINUX_PIPE_FS_I_H
#define _LINUX_PIPE_FS_I_H

#define PIPEFS_MAGIC 0x50495045

#define PIPE_BUFFERS (16)

#define PIPE_BUF_FLAG_STOLEN	0x01
#define PIPE_BUF_FLAG_LRU	0x02

struct pipe_buffer {
	struct page *page;
	unsigned int offset, len;
	struct pipe_buf_operations *ops;
	unsigned int flags;
};

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 *);
	int (*steal)(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;
	struct inode *inode;
};

/* 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_MUTEX(inode)	(&(inode).i_mutex)
#define PIPE_WAIT(inode)	(&(inode).i_pipe->wait)
#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 pipe_inode_info *pipe);

struct pipe_inode_info * alloc_pipe_info(struct inode * inode);
void free_pipe_info(struct inode * inode);

/*
 * splice is tied to pipes as a transport (at least for now), so we'll just
 * add the splice flags here.
 */
#define SPLICE_F_MOVE	(0x01)	/* move pages instead of copying */
#define SPLICE_F_NONBLOCK (0x02) /* don't block on the pipe splicing (but */
				 /* we may still block on the fd we splice */
				 /* from/to, of course */
#define SPLICE_F_MORE	(0x04)	/* expect more data */

#endif
Commit	Line	Data
1da177e4 LT	1	#ifndef _LINUX_PIPE_FS_I_H
	2	#define _LINUX_PIPE_FS_I_H
	3
	4	#define PIPEFS_MAGIC 0x50495045
	5
	6	#define PIPE_BUFFERS (16)
	7
3e7ee3e7 JA	8	#define PIPE_BUF_FLAG_STOLEN 0x01
	9	#define PIPE_BUF_FLAG_LRU 0x02
	10
1da177e4 LT	11	struct pipe_buffer {
	12	struct page *page;
	13	unsigned int offset, len;
	14	struct pipe_buf_operations *ops;
3e7ee3e7	15	unsigned int flags;
1da177e4 LT	16	};
	17
	18	struct pipe_buf_operations {
	19	int can_merge;
	20	void * (map)(struct file , struct pipe_inode_info , struct pipe_buffer );
	21	void (unmap)(struct pipe_inode_info , struct pipe_buffer *);
	22	void (release)(struct pipe_inode_info , struct pipe_buffer *);
5abc97aa	23	int (steal)(struct pipe_inode_info , struct pipe_buffer *);
1da177e4 LT	24	};
	25
	26	struct pipe_inode_info {
	27	wait_queue_head_t wait;
	28	unsigned int nrbufs, curbuf;
	29	struct pipe_buffer bufs[PIPE_BUFFERS];
	30	struct page *tmp_page;
	31	unsigned int start;
	32	unsigned int readers;
	33	unsigned int writers;
	34	unsigned int waiting_writers;
	35	unsigned int r_counter;
	36	unsigned int w_counter;
	37	struct fasync_struct *fasync_readers;
	38	struct fasync_struct *fasync_writers;
3a326a2c	39	struct inode *inode;
1da177e4 LT	40	};
	41
	42	/* Differs from PIPE_BUF in that PIPE_SIZE is the length of the actual
	43	memory allocation, whereas PIPE_BUF makes atomicity guarantees. */
	44	#define PIPE_SIZE PAGE_SIZE
	45
1b1dcc1b	46	#define PIPE_MUTEX(inode) (&(inode).i_mutex)
1da177e4	47	#define PIPE_WAIT(inode) (&(inode).i_pipe->wait)
1da177e4 LT	48	#define PIPE_READERS(inode) ((inode).i_pipe->readers)
	49	#define PIPE_WRITERS(inode) ((inode).i_pipe->writers)
	50	#define PIPE_WAITING_WRITERS(inode) ((inode).i_pipe->waiting_writers)
	51	#define PIPE_RCOUNTER(inode) ((inode).i_pipe->r_counter)
	52	#define PIPE_WCOUNTER(inode) ((inode).i_pipe->w_counter)
	53	#define PIPE_FASYNC_READERS(inode) (&((inode).i_pipe->fasync_readers))
	54	#define PIPE_FASYNC_WRITERS(inode) (&((inode).i_pipe->fasync_writers))
	55
	56	/* Drop the inode semaphore and wait for a pipe event, atomically */
3a326a2c	57	void pipe_wait(struct pipe_inode_info *pipe);
1da177e4	58
3a326a2c IM	59	struct pipe_inode_info * alloc_pipe_info(struct inode * inode);
3a326a2c IM	60	void free_pipe_info(struct inode * inode);
1da177e4	61
5abc97aa JA	62	/*
	63	* splice is tied to pipes as a transport (at least for now), so we'll just
	64	* add the splice flags here.
	65	*/
	66	#define SPLICE_F_MOVE (0x01) /* move pages instead of copying */
29e35094 LT	67	#define SPLICE_F_NONBLOCK (0x02) /* don't block on the pipe splicing (but */
	68	/* we may still block on the fd we splice */
	69	/* from/to, of course */
b2b39fa4	70	#define SPLICE_F_MORE (0x04) /* expect more data */
5abc97aa	71
1da177e4	72	#endif