1 /* 2 * Copyright (c) 2004, 2005 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Hiten Pandya <hmp@backplane.com>. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * $DragonFly: src/sys/sys/bio.h,v 1.3 2006/02/17 19:18:07 dillon Exp $ 35 */ 36 37 #ifndef _SYS_BIO_H_ 38 #define _SYS_BIO_H_ 39 40 #ifndef _SYS_QUEUE_H_ 41 #include <sys/queue.h> 42 #endif 43 44 struct bio; 45 struct bio_track; 46 47 typedef void biodone_t(struct bio *); 48 49 /* 50 * BIO encapsulation for storage drivers and systems that do not require 51 * caching support for underlying blocks. 52 * 53 * NOTE: bio_done and bio_caller_info belong to the caller, while 54 * bio_driver_info belongs to the driver. 55 * 56 * bio_track is only non-NULL when an I/O is in progress. 57 */ 58 struct bio { 59 TAILQ_ENTRY(bio) bio_act; /* driver queue when active */ 60 struct bio_track *bio_track; /* BIO tracking structure */ 61 struct bio *bio_prev; /* BIO stack */ 62 struct bio *bio_next; /* BIO stack / cached translations */ 63 struct buf *bio_buf; /* High-level buffer back-pointer. */ 64 biodone_t *bio_done; /* Caller completion function */ 65 daddr_t bio_blkno; /* Block number relative to device */ 66 off_t bio_offset; /* Logical offset relative to device */ 67 void *bio_driver_info; 68 union { 69 void *ptr; 70 off_t offset; 71 int index; 72 struct buf *cluster_head; 73 struct bio *cluster_parent; 74 } bio_caller_info1; 75 union { 76 void *ptr; 77 off_t offset; 78 int index; 79 struct buf *cluster_tail; 80 } bio_caller_info2; 81 }; 82 83 void bio_start_transaction(struct bio *, struct bio_track *); 84 85 #endif 86