ext2fs_bmap.c revision 1.13
1 /* $NetBSD: ext2fs_bmap.c,v 1.13 2003/10/05 17:48:49 bouyer 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 REGENTS AND CONTRIBUTORS ``AS IS'' AND 58 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 60 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 67 * SUCH DAMAGE. 68 * 69 * @(#)ufs_bmap.c 8.6 (Berkeley) 1/21/94 70 * Modified for ext2fs by Manuel Bouyer. 71 */ 72 73 #include <sys/cdefs.h> 74 __KERNEL_RCSID(0, "$NetBSD: ext2fs_bmap.c,v 1.13 2003/10/05 17:48:49 bouyer Exp $"); 75 76 #include <sys/param.h> 77 #include <sys/systm.h> 78 #include <sys/buf.h> 79 #include <sys/proc.h> 80 #include <sys/vnode.h> 81 #include <sys/mount.h> 82 #include <sys/resourcevar.h> 83 #include <sys/trace.h> 84 85 #include <miscfs/specfs/specdev.h> 86 87 #include <ufs/ufs/inode.h> 88 #include <ufs/ufs/ufsmount.h> 89 #include <ufs/ufs/ufs_extern.h> 90 #include <ufs/ext2fs/ext2fs.h> 91 #include <ufs/ext2fs/ext2fs_extern.h> 92 93 static int ext2fs_bmaparray __P((struct vnode *, daddr_t, daddr_t *, 94 struct indir *, int *, int *)); 95 96 #define is_sequential(ump, a, b) ((b) == (a) + ump->um_seqinc) 97 98 /* 99 * Bmap converts a the logical block number of a file to its physical block 100 * number on the disk. The conversion is done by using the logical block 101 * number to index into the array of block pointers described by the dinode. 102 */ 103 int 104 ext2fs_bmap(v) 105 void *v; 106 { 107 struct vop_bmap_args /* { 108 struct vnode *a_vp; 109 daddr_t a_bn; 110 struct vnode **a_vpp; 111 daddr_t *a_bnp; 112 int *a_runp; 113 } */ *ap = v; 114 /* 115 * Check for underlying vnode requests and ensure that logical 116 * to physical mapping is requested. 117 */ 118 if (ap->a_vpp != NULL) 119 *ap->a_vpp = VTOI(ap->a_vp)->i_devvp; 120 if (ap->a_bnp == NULL) 121 return (0); 122 123 return (ext2fs_bmaparray(ap->a_vp, ap->a_bn, ap->a_bnp, NULL, NULL, 124 ap->a_runp)); 125 } 126 127 /* 128 * Indirect blocks are now on the vnode for the file. They are given negative 129 * logical block numbers. Indirect blocks are addressed by the negative 130 * address of the first data block to which they point. Double indirect blocks 131 * are addressed by one less than the address of the first indirect block to 132 * which they point. Triple indirect blocks are addressed by one less than 133 * the address of the first double indirect block to which they point. 134 * 135 * ext2fs_bmaparray does the bmap conversion, and if requested returns the 136 * array of logical blocks which must be traversed to get to a block. 137 * Each entry contains the offset into that block that gets you to the 138 * next block and the disk address of the block (if it is assigned). 139 */ 140 141 int 142 ext2fs_bmaparray(vp, bn, bnp, ap, nump, runp) 143 struct vnode *vp; 144 daddr_t bn; 145 daddr_t *bnp; 146 struct indir *ap; 147 int *nump; 148 int *runp; 149 { 150 struct inode *ip; 151 struct buf *bp; 152 struct ufsmount *ump; 153 struct mount *mp; 154 struct indir a[NIADDR+1], *xap; 155 daddr_t daddr; 156 daddr_t metalbn; 157 int error, maxrun = 0, num; 158 159 ip = VTOI(vp); 160 mp = vp->v_mount; 161 ump = VFSTOUFS(mp); 162 #ifdef DIAGNOSTIC 163 if ((ap != NULL && nump == NULL) || (ap == NULL && nump != NULL)) 164 panic("ext2fs_bmaparray: invalid arguments"); 165 #endif 166 167 if (runp) { 168 /* 169 * XXX 170 * If MAXBSIZE is the largest transfer the disks can handle, 171 * we probably want maxrun to be 1 block less so that we 172 * don't create a block larger than the device can handle. 173 */ 174 *runp = 0; 175 maxrun = MAXBSIZE / mp->mnt_stat.f_iosize - 1; 176 } 177 178 if (bn >= 0 && bn < NDADDR) { 179 /* XXX ondisk32 */ 180 *bnp = blkptrtodb(ump, (daddr_t)fs2h32(ip->i_e2fs_blocks[bn])); 181 if (*bnp == 0) 182 *bnp = -1; 183 else if (runp) 184 /* XXX ondisk32 */ 185 for (++bn; bn < NDADDR && *runp < maxrun && 186 is_sequential(ump, (daddr_t)fs2h32(ip->i_e2fs_blocks[bn - 1]), 187 (daddr_t)fs2h32(ip->i_e2fs_blocks[bn])); 188 ++bn, ++*runp); 189 return (0); 190 } 191 192 xap = ap == NULL ? a : ap; 193 if (!nump) 194 nump = # 195 if ((error = ufs_getlbns(vp, bn, xap, nump)) != 0) 196 return (error); 197 198 num = *nump; 199 200 /* Get disk address out of indirect block array */ 201 /* XXX ondisk32 */ 202 daddr = fs2h32(ip->i_e2fs_blocks[NDADDR + xap->in_off]); 203 204 #ifdef DIAGNOSTIC 205 if (num > NIADDR + 1 || num < 1) { 206 printf("ext2fs_bmaparray: num=%d\n", num); 207 panic("ext2fs_bmaparray: num"); 208 } 209 #endif 210 for (bp = NULL, ++xap; --num; ++xap) { 211 /* 212 * Exit the loop if there is no disk address assigned yet and 213 * the indirect block isn't in the cache, or if we were 214 * looking for an indirect block and we've found it. 215 */ 216 217 metalbn = xap->in_lbn; 218 if ((daddr == 0 && !incore(vp, metalbn)) || metalbn == bn) 219 break; 220 /* 221 * If we get here, we've either got the block in the cache 222 * or we have a disk address for it, go fetch it. 223 */ 224 if (bp) 225 brelse(bp); 226 227 xap->in_exists = 1; 228 bp = getblk(vp, metalbn, mp->mnt_stat.f_iosize, 0, 0); 229 if (bp->b_flags & (B_DONE | B_DELWRI)) { 230 trace(TR_BREADHIT, pack(vp, size), metalbn); 231 } 232 #ifdef DIAGNOSTIC 233 else if (!daddr) 234 panic("ext2fs_bmaparry: indirect block not in cache"); 235 #endif 236 else { 237 trace(TR_BREADMISS, pack(vp, size), metalbn); 238 bp->b_blkno = blkptrtodb(ump, daddr); 239 bp->b_flags |= B_READ; 240 VOP_STRATEGY(bp); 241 curproc->p_stats->p_ru.ru_inblock++; /* XXX */ 242 if ((error = biowait(bp)) != 0) { 243 brelse(bp); 244 return (error); 245 } 246 } 247 248 /* XXX ondisk32 */ 249 daddr = fs2h32(((int32_t *)bp->b_data)[xap->in_off]); 250 if (num == 1 && daddr && runp) 251 /* XXX ondisk32 */ 252 for (bn = xap->in_off + 1; 253 bn < MNINDIR(ump) && *runp < maxrun && 254 is_sequential(ump, ((int32_t *)bp->b_data)[bn - 1], 255 ((int32_t *)bp->b_data)[bn]); 256 ++bn, ++*runp); 257 } 258 if (bp) 259 brelse(bp); 260 261 daddr = blkptrtodb(ump, daddr); 262 *bnp = daddr == 0 ? -1 : daddr; 263 return (0); 264 } 265
Indexes created Tue Sep 23 23:09:58 GMT 2025