[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_LRU	0x01

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 *);
	void (*get)(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

/* 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);
void __free_pipe_info(struct pipe_inode_info *);

/*
 * 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 */

/*
 * Passed to the actors
 */
struct splice_desc {
	unsigned int len, total_len;	/* current and remaining length */
	unsigned int flags;		/* splice flags */
	struct file *file;		/* file to read/write */
	loff_t pos;			/* file position */
};

typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *,
			   struct splice_desc *);

extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *,
				loff_t *, size_t, unsigned int,
				splice_actor *);

#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
0568b409	8	#define PIPE_BUF_FLAG_LRU 0x01
3e7ee3e7	9
1da177e4 LT	10	struct pipe_buffer {
	11	struct page *page;
	12	unsigned int offset, len;
	13	struct pipe_buf_operations *ops;
3e7ee3e7	14	unsigned int flags;
1da177e4 LT	15	};
	16
	17	struct pipe_buf_operations {
	18	int can_merge;
	19	void * (map)(struct file , struct pipe_inode_info , struct pipe_buffer );
	20	void (unmap)(struct pipe_inode_info , struct pipe_buffer *);
	21	void (release)(struct pipe_inode_info , struct pipe_buffer *);
5abc97aa	22	int (steal)(struct pipe_inode_info , struct pipe_buffer *);
70524490	23	void (get)(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
1da177e4	46	/* Drop the inode semaphore and wait for a pipe event, atomically */
3a326a2c	47	void pipe_wait(struct pipe_inode_info *pipe);
1da177e4	48
3a326a2c IM	49	struct pipe_inode_info * alloc_pipe_info(struct inode * inode);
3a326a2c IM	50	void free_pipe_info(struct inode * inode);
b92ce558	51	void __free_pipe_info(struct pipe_inode_info *);
1da177e4	52
5abc97aa JA	53	/*
	54	* splice is tied to pipes as a transport (at least for now), so we'll just
	55	* add the splice flags here.
	56	*/
	57	#define SPLICE_F_MOVE (0x01) /* move pages instead of copying */
29e35094 LT	58	#define SPLICE_F_NONBLOCK (0x02) /* don't block on the pipe splicing (but */
	59	/* we may still block on the fd we splice */
	60	/* from/to, of course */
b2b39fa4	61	#define SPLICE_F_MORE (0x04) /* expect more data */
5abc97aa	62
00522fb4 JA	63	/*
	64	* Passed to the actors
	65	*/
	66	struct splice_desc {
	67	unsigned int len, total_len; /* current and remaining length */
	68	unsigned int flags; /* splice flags */
	69	struct file file; / file to read/write */
	70	loff_t pos; /* file position */
	71	};
	72
	73	typedef int (splice_actor)(struct pipe_inode_info , struct pipe_buffer ,
	74	struct splice_desc *);
	75
	76	extern ssize_t splice_from_pipe(struct pipe_inode_info , struct file ,
	77	loff_t *, size_t, unsigned int,
	78	splice_actor *);
	79
1da177e4	80	#endif