From d6b29d7cee064f28ca097e906de7453541351095 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Mon, 4 Jun 2007 09:59:47 +0200 Subject: splice: divorce the splice structure/function definitions from the pipe header We need to move even more stuff into the header so that folks can use the splice_to_pipe() implementation instead of open-coding a lot of pipe knowledge (see relay implementation), so move to our own header file finally. Signed-off-by: Jens Axboe --- include/linux/splice.h | 72 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 72 insertions(+) create mode 100644 include/linux/splice.h (limited to 'include/linux/splice.h') diff --git a/include/linux/splice.h b/include/linux/splice.h new file mode 100644 index 0000000..f8cc97f --- /dev/null +++ b/include/linux/splice.h @@ -0,0 +1,72 @@ +/* + * Function declerations and data structures related to the splice + * implementation. + * + * Copyright (C) 2007 Jens Axboe + * + */ +#ifndef SPLICE_H +#define SPLICE_H + +#include + +/* + * 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 */ +#define SPLICE_F_GIFT (0x08) /* pages passed in are a gift */ + +/* + * Passed to the actors + */ +struct splice_desc { + unsigned int len, total_len; /* current and remaining length */ + unsigned int flags; /* splice flags */ + /* + * actor() private data + */ + union { + void __user *userptr; /* memory to write to */ + struct file *file; /* file to read/write */ + void *data; /* cookie */ + } u; + loff_t pos; /* file position */ +}; + +struct partial_page { + unsigned int offset; + unsigned int len; +}; + +/* + * Passed to splice_to_pipe + */ +struct splice_pipe_desc { + struct page **pages; /* page map */ + struct partial_page *partial; /* pages[] may not be contig */ + int nr_pages; /* number of pages in map */ + unsigned int flags; /* splice flags */ + const struct pipe_buf_operations *ops;/* ops associated with output pipe */ +}; + +typedef int (splice_actor)(struct pipe_inode_info *, struct pipe_buffer *, + struct splice_desc *); +typedef int (splice_direct_actor)(struct pipe_inode_info *, + struct splice_desc *); + +extern ssize_t splice_from_pipe(struct pipe_inode_info *, struct file *, + loff_t *, size_t, unsigned int, + splice_actor *); +extern ssize_t __splice_from_pipe(struct pipe_inode_info *, + struct splice_desc *, splice_actor *); +extern ssize_t splice_to_pipe(struct pipe_inode_info *, + struct splice_pipe_desc *); +extern ssize_t splice_direct_to_actor(struct file *, struct splice_desc *, + splice_direct_actor *); + +#endif -- cgit v1.1