kern_conf.c revision 31352
1/*- 2 * Parts Copyright (c) 1995 Terrence R. Lambert 3 * Copyright (c) 1995 Julian R. Elischer 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 3. All advertising materials mentioning features or use of this software 15 * must display the following acknowledgement: 16 * This product includes software developed by Terrence R. Lambert. 17 * 4. The name Terrence R. Lambert may not be used to endorse or promote 18 * products derived from this software without specific prior written 19 * permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY Julian R. Elischer ``AS IS'' AND ANY 22 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $Id: kern_conf.c,v 1.22 1997/09/27 13:39:03 kato Exp $ 34 */ 35 36#include <sys/param.h> 37#include <sys/systm.h> 38#include <sys/conf.h> 39#include <sys/vnode.h> 40 41#define NUMBDEV 128 42#define NUMCDEV 256 43#define bdevsw_ALLOCSTART (NUMBDEV/2) 44#define cdevsw_ALLOCSTART (NUMCDEV/2) 45 46struct bdevsw *bdevsw[NUMBDEV]; 47int nblkdev = NUMBDEV; 48struct cdevsw *cdevsw[NUMCDEV]; 49int nchrdev = NUMCDEV; 50 51static void cdevsw_make __P((struct bdevsw *from)); 52static int isdisk __P((dev_t dev, int type)); 53 54/* 55 * Routine to determine if a device is a disk. 56 * 57 * KLUDGE XXX add flags to cdevsw entries for disks XXX 58 * A minimal stub routine can always return 0. 59 */ 60static int 61isdisk(dev, type) 62 dev_t dev; 63 int type; 64{ 65 66 switch (major(dev)) { 67 case 15: /* VBLK: vn, VCHR: cd */ 68 return (1); 69 case 0: /* wd */ 70 case 2: /* fd */ 71 case 4: /* sd */ 72 case 6: /* cd */ 73 case 7: /* mcd */ 74 case 16: /* scd */ 75 case 17: /* matcd */ 76 case 18: /* ata */ 77 case 19: /* wcd */ 78 case 20: /* od */ 79 case 22: /* gd */ 80 if (type == VBLK) 81 return (1); 82 return (0); 83 case 3: /* wd */ 84 case 9: /* fd */ 85 case 13: /* sd */ 86 case 29: /* mcd */ 87 case 43: /* vn */ 88 case 45: /* scd */ 89 case 46: /* matcd */ 90 case 69: /* wcd */ 91 case 70: /* od */ 92 case 78: /* gd */ 93 if (type == VCHR) 94 return (1); 95 /* fall through */ 96 default: 97 return (0); 98 } 99 /* NOTREACHED */ 100} 101 102 103/* 104 * Routine to convert from character to block device number. 105 * 106 * A minimal stub routine can always return NODEV. 107 */ 108dev_t 109chrtoblk(dev_t dev) 110{ 111 struct bdevsw *bd; 112 struct cdevsw *cd; 113 114 if(cd = cdevsw[major(dev)]) { 115 if ( (bd = cd->d_bdev) ) 116 return(makedev(bd->d_maj,minor(dev))); 117 } 118 return(NODEV); 119} 120 121/* 122 * (re)place an entry in the bdevsw or cdevsw table 123 * return the slot used in major(*descrip) 124 */ 125#define ADDENTRY(TTYPE,NXXXDEV,ALLOCSTART) \ 126int TTYPE##_add(dev_t *descrip, \ 127 struct TTYPE *newentry, \ 128 struct TTYPE **oldentry) \ 129{ \ 130 int i ; \ 131 if ( (int)*descrip == NODEV) { /* auto (0 is valid) */ \ 132 /* \ 133 * Search the table looking for a slot... \ 134 */ \ 135 for (i = ALLOCSTART; i < NXXXDEV; i++) \ 136 if (TTYPE[i] == NULL) \ 137 break; /* found one! */ \ 138 /* out of allocable slots? */ \ 139 if (i >= NXXXDEV) { \ 140 return ENFILE; \ 141 } \ 142 } else { /* assign */ \ 143 i = major(*descrip); \ 144 if (i < 0 || i >= NXXXDEV) { \ 145 return EINVAL; \ 146 } \ 147 } \ 148 \ 149 /* maybe save old */ \ 150 if (oldentry) { \ 151 *oldentry = TTYPE[i]; \ 152 } \ 153 if (newentry) \ 154 newentry->d_maj = i; \ 155 /* replace with new */ \ 156 TTYPE[i] = newentry; \ 157 \ 158 /* done! let them know where we put it */ \ 159 *descrip = makedev(i,0); \ 160 return 0; \ 161} \ 162 163ADDENTRY(bdevsw, nblkdev,bdevsw_ALLOCSTART) 164ADDENTRY(cdevsw, nchrdev,cdevsw_ALLOCSTART) 165 166/* 167 * Since the bdevsw struct for a disk contains all the information 168 * needed to create a cdevsw entry, these two routines do that, rather 169 * than specifying it by hand. 170 */ 171 172static void 173cdevsw_make(struct bdevsw *from) 174{ 175 struct cdevsw *to = from->d_cdev; 176 177 if (!to) 178 panic("No target cdevsw in bdevsw"); 179 to->d_open = from->d_open; 180 to->d_close = from->d_close; 181 to->d_read = rawread; 182 to->d_write = rawwrite; 183 to->d_ioctl = from->d_ioctl; 184 to->d_stop = nostop; 185 to->d_reset = nullreset; 186 to->d_devtotty = nodevtotty; 187 to->d_poll = seltrue; 188 to->d_mmap = nommap; 189 to->d_strategy = from->d_strategy; 190 to->d_name = from->d_name; 191 to->d_bdev = from; 192 to->d_maj = -1; 193} 194 195void 196bdevsw_add_generic(int bdev, int cdev, struct bdevsw *bdevsw) 197{ 198 dev_t dev; 199 /* 200 * XXX hack alert. 201 */ 202 if (isdisk(makedev(bdev, 0), VBLK) && 203 (bdevsw->d_flags & D_TYPEMASK) != D_DISK) { 204 printf("bdevsw_add_generic: adding D_DISK flag for device %d\n", 205 bdev); 206 bdevsw->d_flags &= ~D_TYPEMASK; 207 bdevsw->d_flags |= D_DISK; 208 } 209 cdevsw_make(bdevsw); 210 dev = makedev(cdev, 0); 211 cdevsw_add(&dev, bdevsw->d_cdev, NULL); 212 dev = makedev(bdev, 0); 213 bdevsw_add(&dev, bdevsw , NULL); 214} 215