1 /*- 2 * modified for Lites 1.1 3 * 4 * Aug 1995, Godmar Back (gback@cs.utah.edu) 5 * University of Utah, Department of Computer Science 6 */ 7 /*- 8 * Copyright (c) 1982, 1986, 1989, 1993 9 * The Regents of the University of California. All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 4. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)ffs_balloc.c 8.4 (Berkeley) 9/23/93 36 * $FreeBSD$ 37 */ 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/bio.h> 42 #include <sys/buf.h> 43 #include <sys/lock.h> 44 #include <sys/mount.h> 45 #include <sys/vnode.h> 46 47 #include <fs/ext2fs/inode.h> 48 #include <fs/ext2fs/ext2fs.h> 49 #include <fs/ext2fs/fs.h> 50 #include <fs/ext2fs/ext2_extern.h> 51 #include <fs/ext2fs/ext2_mount.h> 52 /* 53 * Balloc defines the structure of file system storage 54 * by allocating the physical blocks on a device given 55 * the inode and the logical block number in a file. 56 */ 57 int 58 ext2_balloc(ip, lbn, size, cred, bpp, flags) 59 struct inode *ip; 60 int32_t lbn; 61 int size; 62 struct ucred *cred; 63 struct buf **bpp; 64 int flags; 65 { 66 struct m_ext2fs *fs; 67 struct ext2mount *ump; 68 int32_t nb; 69 struct buf *bp, *nbp; 70 struct vnode *vp = ITOV(ip); 71 struct indir indirs[NIADDR + 2]; 72 int32_t newb, *bap, pref; 73 int osize, nsize, num, i, error; 74 75 *bpp = NULL; 76 if (lbn < 0) 77 return (EFBIG); 78 fs = ip->i_e2fs; 79 ump = ip->i_ump; 80 81 /* 82 * check if this is a sequential block allocation. 83 * If so, increment next_alloc fields to allow ext2_blkpref 84 * to make a good guess 85 */ 86 if (lbn == ip->i_next_alloc_block + 1) { 87 ip->i_next_alloc_block++; 88 ip->i_next_alloc_goal++; 89 } 90 91 /* 92 * The first NDADDR blocks are direct blocks 93 */ 94 if (lbn < NDADDR) { 95 nb = ip->i_db[lbn]; 96 /* no new block is to be allocated, and no need to expand 97 the file */ 98 if (nb != 0 && ip->i_size >= (lbn + 1) * fs->e2fs_bsize) { 99 error = bread(vp, lbn, fs->e2fs_bsize, NOCRED, &bp); 100 if (error) { 101 brelse(bp); 102 return (error); 103 } 104 bp->b_blkno = fsbtodb(fs, nb); 105 *bpp = bp; 106 return (0); 107 } 108 if (nb != 0) { 109 /* 110 * Consider need to reallocate a fragment. 111 */ 112 osize = fragroundup(fs, blkoff(fs, ip->i_size)); 113 nsize = fragroundup(fs, size); 114 if (nsize <= osize) { 115 error = bread(vp, lbn, osize, NOCRED, &bp); 116 if (error) { 117 brelse(bp); 118 return (error); 119 } 120 bp->b_blkno = fsbtodb(fs, nb); 121 } else { 122 /* Godmar thinks: this shouldn't happen w/o fragments */ 123 printf("nsize %d(%d) > osize %d(%d) nb %d\n", 124 (int)nsize, (int)size, (int)osize, 125 (int)ip->i_size, (int)nb); 126 panic( 127 "ext2_balloc: Something is terribly wrong"); 128 /* 129 * please note there haven't been any changes from here on - 130 * FFS seems to work. 131 */ 132 } 133 } else { 134 if (ip->i_size < (lbn + 1) * fs->e2fs_bsize) 135 nsize = fragroundup(fs, size); 136 else 137 nsize = fs->e2fs_bsize; 138 EXT2_LOCK(ump); 139 error = ext2_alloc(ip, lbn, 140 ext2_blkpref(ip, lbn, (int)lbn, &ip->i_db[0], 0), 141 nsize, cred, &newb); 142 if (error) 143 return (error); 144 bp = getblk(vp, lbn, nsize, 0, 0, 0); 145 bp->b_blkno = fsbtodb(fs, newb); 146 if (flags & BA_CLRBUF) 147 vfs_bio_clrbuf(bp); 148 } 149 ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno); 150 ip->i_flag |= IN_CHANGE | IN_UPDATE; 151 *bpp = bp; 152 return (0); 153 } 154 /* 155 * Determine the number of levels of indirection. 156 */ 157 pref = 0; 158 if ((error = ext2_getlbns(vp, lbn, indirs, &num)) != 0) 159 return (error); 160 #ifdef DIAGNOSTIC 161 if (num < 1) 162 panic ("ext2_balloc: ext2_getlbns returned indirect block"); 163 #endif 164 /* 165 * Fetch the first indirect block allocating if necessary. 166 */ 167 --num; 168 nb = ip->i_ib[indirs[0].in_off]; 169 if (nb == 0) { 170 EXT2_LOCK(ump); 171 pref = ext2_blkpref(ip, lbn, indirs[0].in_off + 172 EXT2_NDIR_BLOCKS, &ip->i_db[0], 0); 173 if ((error = ext2_alloc(ip, lbn, pref, 174 (int)fs->e2fs_bsize, cred, &newb))) 175 return (error); 176 nb = newb; 177 bp = getblk(vp, indirs[1].in_lbn, fs->e2fs_bsize, 0, 0, 0); 178 bp->b_blkno = fsbtodb(fs, newb); 179 vfs_bio_clrbuf(bp); 180 /* 181 * Write synchronously so that indirect blocks 182 * never point at garbage. 183 */ 184 if ((error = bwrite(bp)) != 0) { 185 ext2_blkfree(ip, nb, fs->e2fs_bsize); 186 return (error); 187 } 188 ip->i_ib[indirs[0].in_off] = newb; 189 ip->i_flag |= IN_CHANGE | IN_UPDATE; 190 } 191 /* 192 * Fetch through the indirect blocks, allocating as necessary. 193 */ 194 for (i = 1;;) { 195 error = bread(vp, 196 indirs[i].in_lbn, (int)fs->e2fs_bsize, NOCRED, &bp); 197 if (error) { 198 brelse(bp); 199 return (error); 200 } 201 bap = (int32_t *)bp->b_data; 202 nb = bap[indirs[i].in_off]; 203 if (i == num) 204 break; 205 i += 1; 206 if (nb != 0) { 207 bqrelse(bp); 208 continue; 209 } 210 EXT2_LOCK(ump); 211 if (pref == 0) 212 pref = ext2_blkpref(ip, lbn, indirs[i].in_off, bap, 213 bp->b_lblkno); 214 error = ext2_alloc(ip, lbn, pref, (int)fs->e2fs_bsize, cred, &newb); 215 if (error) { 216 brelse(bp); 217 return (error); 218 } 219 nb = newb; 220 nbp = getblk(vp, indirs[i].in_lbn, fs->e2fs_bsize, 0, 0, 0); 221 nbp->b_blkno = fsbtodb(fs, nb); 222 vfs_bio_clrbuf(nbp); 223 /* 224 * Write synchronously so that indirect blocks 225 * never point at garbage. 226 */ 227 if ((error = bwrite(nbp)) != 0) { 228 ext2_blkfree(ip, nb, fs->e2fs_bsize); 229 EXT2_UNLOCK(ump); 230 brelse(bp); 231 return (error); 232 } 233 bap[indirs[i - 1].in_off] = nb; 234 /* 235 * If required, write synchronously, otherwise use 236 * delayed write. 237 */ 238 if (flags & IO_SYNC) { 239 bwrite(bp); 240 } else { 241 if (bp->b_bufsize == fs->e2fs_bsize) 242 bp->b_flags |= B_CLUSTEROK; 243 bdwrite(bp); 244 } 245 } 246 /* 247 * Get the data block, allocating if necessary. 248 */ 249 if (nb == 0) { 250 EXT2_LOCK(ump); 251 pref = ext2_blkpref(ip, lbn, indirs[i].in_off, &bap[0], 252 bp->b_lblkno); 253 if ((error = ext2_alloc(ip, 254 lbn, pref, (int)fs->e2fs_bsize, cred, &newb)) != 0) { 255 brelse(bp); 256 return (error); 257 } 258 nb = newb; 259 nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0, 0); 260 nbp->b_blkno = fsbtodb(fs, nb); 261 if (flags & BA_CLRBUF) 262 vfs_bio_clrbuf(nbp); 263 bap[indirs[i].in_off] = nb; 264 /* 265 * If required, write synchronously, otherwise use 266 * delayed write. 267 */ 268 if (flags & IO_SYNC) { 269 bwrite(bp); 270 } else { 271 if (bp->b_bufsize == fs->e2fs_bsize) 272 bp->b_flags |= B_CLUSTEROK; 273 bdwrite(bp); 274 } 275 *bpp = nbp; 276 return (0); 277 } 278 brelse(bp); 279 if (flags & BA_CLRBUF) { 280 int seqcount = (flags & BA_SEQMASK) >> BA_SEQSHIFT; 281 if (seqcount && (vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) { 282 error = cluster_read(vp, ip->i_size, lbn, 283 (int)fs->e2fs_bsize, NOCRED, 284 MAXBSIZE, seqcount, &nbp); 285 } else { 286 error = bread(vp, lbn, (int)fs->e2fs_bsize, NOCRED, &nbp); 287 } 288 if (error) { 289 brelse(nbp); 290 return (error); 291 } 292 } else { 293 nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0, 0); 294 nbp->b_blkno = fsbtodb(fs, nb); 295 } 296 *bpp = nbp; 297 return (0); 298 } 299 300