/* * Function declerations and data structures related to the splice * implementation. * * Copyright (C) 2007 Jens Axboe <jens.axboe@oracle.com> * */ #ifndef SPLICE_H #define SPLICE_H #include <linux/pipe_fs_i.h> /* * Flags passed in from splice/tee/vmsplice */ #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 */ size_t num_spliced; /* number of bytes already spliced */ bool need_wakeup; /* need to wake up writer */ }; struct partial_page { unsigned int offset; unsigned int len; unsigned long private; }; /* * 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 */ void (*spd_release)(struct splice_pipe_desc *, unsigned int); }; 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 int splice_from_pipe_feed(struct pipe_inode_info *, struct splice_desc *, splice_actor *); extern int splice_from_pipe_next(struct pipe_inode_info *, struct splice_desc *); extern void splice_from_pipe_begin(struct splice_desc *); extern void splice_from_pipe_end(struct pipe_inode_info *, struct splice_desc *); extern int pipe_to_file(struct pipe_inode_info *, struct pipe_buffer *, struct splice_desc *); 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 *); /* * for dynamic pipe sizing */ extern int splice_grow_spd(struct pipe_inode_info *, struct splice_pipe_desc *); extern void splice_shrink_spd(struct pipe_inode_info *, struct splice_pipe_desc *); extern void spd_release_page(struct splice_pipe_desc *, unsigned int); extern const struct pipe_buf_operations page_cache_pipe_buf_ops; #endif