ext2fs_bmap.c revision 1.17
1 /* $NetBSD: ext2fs_bmap.c,v 1.17 2004/12/15 07:11:51 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 1989, 1991, 1993 5 * The Regents of the University of California. All rights reserved. 6 * (c) UNIX System Laboratories, Inc. 7 * All or some portions of this file are derived from material licensed 8 * to the University of California by American Telephone and Telegraph 9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 10 * the permission of UNIX System Laboratories, Inc. 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. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)ufs_bmap.c 8.6 (Berkeley) 1/21/94 37 * Modified for ext2fs by Manuel Bouyer. 38 */ 39 40 /* 41 * Copyright (c) 1997 Manuel Bouyer. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by Manuel Bouyer. 54 * 4. The name of the author may not be used to endorse or promote products 55 * derived from this software without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 60 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 61 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 62 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 63 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 64 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 65 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 66 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 67 * 68 * @(#)ufs_bmap.c 8.6 (Berkeley) 1/21/94 69 * Modified for ext2fs by Manuel Bouyer. 70 */ 71 72 #include <sys/cdefs.h> 73 __KERNEL_RCSID(0, "$NetBSD: ext2fs_bmap.c,v 1.17 2004/12/15 07:11:51 mycroft Exp $"); 74 75 #include <sys/param.h> 76 #include <sys/systm.h> 77 #include <sys/buf.h> 78 #include <sys/proc.h> 79 #include <sys/vnode.h> 80 #include <sys/mount.h> 81 #include <sys/resourcevar.h> 82 #include <sys/trace.h> 83 84 #include <miscfs/specfs/specdev.h> 85 86 #include <ufs/ufs/inode.h> 87 #include <ufs/ufs/ufsmount.h> 88 #include <ufs/ufs/ufs_extern.h> 89 #include <ufs/ext2fs/ext2fs.h> 90 #include <ufs/ext2fs/ext2fs_extern.h> 91 92 static int ext2fs_bmaparray __P((struct vnode *, daddr_t, daddr_t *, 93 struct indir *, int *, int *)); 94 95 #define is_sequential(ump, a, b) ((b) == (a) + ump->um_seqinc) 96 97 /* 98 * Bmap converts a the logical block number of a file to its physical block 99 * number on the disk. The conversion is done by using the logical block 100 * number to index into the array of block pointers described by the dinode. 101 */ 102 int 103 ext2fs_bmap(v) 104 void *v; 105 { 106 struct vop_bmap_args /* { 107 struct vnode *a_vp; 108 daddr_t a_bn; 109 struct vnode **a_vpp; 110 daddr_t *a_bnp; 111 int *a_runp; 112 } */ *ap = v; 113 /* 114 * Check for underlying vnode requests and ensure that logical 115 * to physical mapping is requested. 116 */ 117 if (ap->a_vpp != NULL) 118 *ap->a_vpp = VTOI(ap->a_vp)->i_devvp; 119 if (ap->a_bnp == NULL) 120 return (0); 121 122 return (ext2fs_bmaparray(ap->a_vp, ap->a_bn, ap->a_bnp, NULL, NULL, 123 ap->a_runp)); 124 } 125 126 /* 127 * Indirect blocks are now on the vnode for the file. They are given negative 128 * logical block numbers. Indirect blocks are addressed by the negative 129 * address of the first data block to which they point. Double indirect blocks 130 * are addressed by one less than the address of the first indirect block to 131 * which they point. Triple indirect blocks are addressed by one less than 132 * the address of the first double indirect block to which they point. 133 * 134 * ext2fs_bmaparray does the bmap conversion, and if requested returns the 135 * array of logical blocks which must be traversed to get to a block. 136 * Each entry contains the offset into that block that gets you to the 137 * next block and the disk address of the block (if it is assigned). 138 */ 139 140 int 141 ext2fs_bmaparray(vp, bn, bnp, ap, nump, runp) 142 struct vnode *vp; 143 daddr_t bn; 144 daddr_t *bnp; 145 struct indir *ap; 146 int *nump; 147 int *runp; 148 { 149 struct inode *ip; 150 struct buf *bp; 151 struct ufsmount *ump; 152 struct mount *mp; 153 struct indir a[NIADDR+1], *xap; 154 daddr_t daddr; 155 daddr_t metalbn; 156 int error, maxrun = 0, num; 157 158 ip = VTOI(vp); 159 mp = vp->v_mount; 160 ump = ip->i_ump; 161 #ifdef DIAGNOSTIC 162 if ((ap != NULL && nump == NULL) || (ap == NULL && nump != NULL)) 163 panic("ext2fs_bmaparray: invalid arguments"); 164 #endif 165 166 if (runp) { 167 /* 168 * XXX 169 * If MAXBSIZE is the largest transfer the disks can handle, 170 * we probably want maxrun to be 1 block less so that we 171 * don't create a block larger than the device can handle. 172 */ 173 *runp = 0; 174 maxrun = MAXBSIZE / mp->mnt_stat.f_iosize - 1; 175 } 176 177 if (bn >= 0 && bn < NDADDR) { 178 /* XXX ondisk32 */ 179 *bnp = blkptrtodb(ump, fs2h32(ip->i_e2fs_blocks[bn])); 180 if (*bnp == 0) 181 *bnp = -1; 182 else if (runp) 183 /* XXX ondisk32 */ 184 for (++bn; bn < NDADDR && *runp < maxrun && 185 is_sequential(ump, (daddr_t)fs2h32(ip->i_e2fs_blocks[bn - 1]), 186 (daddr_t)fs2h32(ip->i_e2fs_blocks[bn])); 187 ++bn, ++*runp); 188 return (0); 189 } 190 191 xap = ap == NULL ? a : ap; 192 if (!nump) 193 nump = # 194 if ((error = ufs_getlbns(vp, bn, xap, nump)) != 0) 195 return (error); 196 197 num = *nump; 198 199 /* Get disk address out of indirect block array */ 200 /* XXX ondisk32 */ 201 daddr = fs2h32(ip->i_e2fs_blocks[NDADDR + xap->in_off]); 202 203 #ifdef DIAGNOSTIC 204 if (num > NIADDR + 1 || num < 1) { 205 printf("ext2fs_bmaparray: num=%d\n", num); 206 panic("ext2fs_bmaparray: num"); 207 } 208 #endif 209 for (bp = NULL, ++xap; --num; ++xap) { 210 /* 211 * Exit the loop if there is no disk address assigned yet and 212 * the indirect block isn't in the cache, or if we were 213 * looking for an indirect block and we've found it. 214 */ 215 216 metalbn = xap->in_lbn; 217 if ((daddr == 0 && !incore(vp, metalbn)) || metalbn == bn) 218 break; 219 /* 220 * If we get here, we've either got the block in the cache 221 * or we have a disk address for it, go fetch it. 222 */ 223 if (bp) 224 brelse(bp); 225 226 xap->in_exists = 1; 227 bp = getblk(vp, metalbn, mp->mnt_stat.f_iosize, 0, 0); 228 if (bp->b_flags & (B_DONE | B_DELWRI)) { 229 trace(TR_BREADHIT, pack(vp, size), metalbn); 230 } 231 #ifdef DIAGNOSTIC 232 else if (!daddr) 233 panic("ext2fs_bmaparry: indirect block not in cache"); 234 #endif 235 else { 236 trace(TR_BREADMISS, pack(vp, size), metalbn); 237 bp->b_blkno = blkptrtodb(ump, daddr); 238 bp->b_flags |= B_READ; 239 VOP_STRATEGY(vp, bp); 240 curproc->p_stats->p_ru.ru_inblock++; /* XXX */ 241 if ((error = biowait(bp)) != 0) { 242 brelse(bp); 243 return (error); 244 } 245 } 246 247 /* XXX ondisk32 */ 248 daddr = fs2h32(((int32_t *)bp->b_data)[xap->in_off]); 249 if (num == 1 && daddr && runp) 250 /* XXX ondisk32 */ 251 for (bn = xap->in_off + 1; 252 bn < MNINDIR(ump) && *runp < maxrun && 253 is_sequential(ump, ((int32_t *)bp->b_data)[bn - 1], 254 ((int32_t *)bp->b_data)[bn]); 255 ++bn, ++*runp); 256 } 257 if (bp) 258 brelse(bp); 259 260 daddr = blkptrtodb(ump, daddr); 261 *bnp = daddr == 0 ? -1 : daddr; 262 return (0); 263 } 264
Indexes created Thu Sep 25 02:09:54 GMT 2025