1 /* $NetBSD: ccdvar.h,v 1.4 1995/03/26 20:28:51 jtc Exp $ */ 2 3 /* 4 * Copyright (c) 1988 University of Utah. 5 * Copyright (c) 1990, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by the University of 23 * California, Berkeley and its contributors. 24 * 4. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * from: Utah $Hdr: cdvar.h 1.1 90/07/09$ 41 * 42 * @(#)cdvar.h 8.1 (Berkeley) 6/10/93 43 */ 44 45 #define NCCDISKS 8 /* max # of component disks */ 46 47 /* 48 * A concatenated disk is described at config time by this structure. 49 */ 50 struct ccddevice { 51 int ccd_unit; /* logical unit of this ccd */ 52 int ccd_interleave; /* interleave (DEV_BSIZE blocks) */ 53 int ccd_flags; /* misc. information */ 54 int ccd_dk; /* disk number */ 55 dev_t ccd_dev[NCCDISKS]; /* component devices */ 56 }; 57 58 /* ccd_flags */ 59 #define CCDF_SWAP 0x01 /* interleave should be dmmax */ 60 #define CCDF_UNIFORM 0x02 /* use LCCD of sizes for uniform interleave */ 61 62 /* 63 * Component info table. 64 * Describes a single component of a concatenated disk. 65 */ 66 struct ccdcinfo { 67 dev_t ci_dev; /* devno */ 68 size_t ci_size; /* size */ 69 }; 70 71 /* 72 * Interleave description table. 73 * Computed at boot time to speed irregular-interleave lookups. 74 * The idea is that we interleave in "groups". First we interleave 75 * evenly over all component disks up to the size of the smallest 76 * component (the first group), then we interleave evenly over all 77 * remaining disks up to the size of the next-smallest (second group), 78 * and so on. 79 * 80 * Each table entry describes the interleave characteristics of one 81 * of these groups. For example if a concatenated disk consisted of 82 * three components of 5, 3, and 7 DEV_BSIZE blocks interleaved at 83 * DEV_BSIZE (1), the table would have three entries: 84 * 85 * ndisk startblk startoff dev 86 * 3 0 0 0, 1, 2 87 * 2 9 3 0, 2 88 * 1 13 5 2 89 * 0 - - - 90 * 91 * which says that the first nine blocks (0-8) are interleaved over 92 * 3 disks (0, 1, 2) starting at block offset 0 on any component disk, 93 * the next 4 blocks (9-12) are interleaved over 2 disks (0, 2) starting 94 * at component block 3, and the remaining blocks (13-14) are on disk 95 * 2 starting at offset 5. 96 */ 97 struct ccdiinfo { 98 int ii_ndisk; /* # of disks range is interleaved over */ 99 daddr_t ii_startblk; /* starting scaled block # for range */ 100 daddr_t ii_startoff; /* starting component offset (block #) */ 101 char ii_index[NCCDISKS];/* ordered list of components in range */ 102 }; 103 104 #ifdef _KERNEL 105 extern struct ccddevice ccddevice[]; 106 #endif 107