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 1.6 2008/07/14 03:08:58 dillon Exp $ 35 */ 36 37 #ifndef _SYS_BIO_H_ 38 #define _SYS_BIO_H_ 39 40 #ifndef _SYS_TYPES_H_ 41 #include <sys/types.h> 42 #endif 43 #ifndef _SYS_QUEUE_H_ 44 #include <sys/queue.h> 45 #endif 46 47 struct bio; 48 struct bio_track; 49 50 typedef void biodone_t(struct bio *); 51 52 /* 53 * BIO encapsulation for storage drivers and systems that do not require 54 * caching support for underlying blocks. 55 * 56 * NOTE: bio_done and bio_caller_info belong to the caller, while 57 * bio_driver_info belongs to the driver. 58 * 59 * bio_track is only non-NULL when an I/O is in progress. 60 */ 61 struct bio { 62 TAILQ_ENTRY(bio) bio_act; /* driver queue when active */ 63 struct bio_track *bio_track; /* BIO tracking structure */ 64 struct bio *bio_prev; /* BIO stack */ 65 struct bio *bio_next; /* BIO stack / cached translations */ 66 struct buf *bio_buf; /* High-level buffer back-pointer. */ 67 biodone_t *bio_done; /* Caller completion function */ 68 off_t bio_offset; /* Logical offset relative to device */ 69 void *bio_driver_info; 70 int bio_flags; 71 union { 72 void *ptr; 73 off_t offset; 74 int index; 75 u_int32_t uvalue32; 76 struct buf *cluster_head; 77 struct bio *cluster_parent; 78 } bio_caller_info1; 79 union { 80 void *ptr; 81 off_t offset; 82 int index; 83 struct buf *cluster_tail; 84 } bio_caller_info2; 85 }; 86 87 /* 88 * BIO flags, used for strategy/biodone/biodone_sync interactions. 89 */ 90 #define BIO_SYNC 0x00000001 91 #define BIO_WANT 0x20000000 92 #define BIO_DONE 0x40000000 93 94 void bio_start_transaction(struct bio *, struct bio_track *); 95 96 #endif 97