ffs_balloc.c revision 1.1.1.2
1 /* 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY 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 REGENTS OR CONTRIBUTORS 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 * @(#)ffs_balloc.c 8.8 (Berkeley) 6/16/95 34 */ 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/buf.h> 39 #include <sys/proc.h> 40 #include <sys/file.h> 41 #include <sys/vnode.h> 42 43 #include <vm/vm.h> 44 45 #include <ufs/ufs/quota.h> 46 #include <ufs/ufs/inode.h> 47 #include <ufs/ufs/ufs_extern.h> 48 49 #include <ufs/ffs/fs.h> 50 #include <ufs/ffs/ffs_extern.h> 51 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 ffs_balloc(ip, lbn, size, cred, bpp, flags) 58 register struct inode *ip; 59 register ufs_daddr_t lbn; 60 int size; 61 struct ucred *cred; 62 struct buf **bpp; 63 int flags; 64 { 65 register struct fs *fs; 66 register ufs_daddr_t nb; 67 struct buf *bp, *nbp; 68 struct vnode *vp = ITOV(ip); 69 struct indir indirs[NIADDR + 2]; 70 ufs_daddr_t newb, *bap, pref; 71 int deallocated, osize, nsize, num, i, error; 72 ufs_daddr_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1]; 73 74 *bpp = NULL; 75 if (lbn < 0) 76 return (EFBIG); 77 fs = ip->i_fs; 78 79 /* 80 * If the next write will extend the file into a new block, 81 * and the file is currently composed of a fragment 82 * this fragment has to be extended to be a full block. 83 */ 84 nb = lblkno(fs, ip->i_size); 85 if (nb < NDADDR && nb < lbn) { 86 osize = blksize(fs, ip, nb); 87 if (osize < fs->fs_bsize && osize > 0) { 88 error = ffs_realloccg(ip, nb, 89 ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]), 90 osize, (int)fs->fs_bsize, cred, &bp); 91 if (error) 92 return (error); 93 ip->i_size = (nb + 1) * fs->fs_bsize; 94 vnode_pager_setsize(vp, (u_long)ip->i_size); 95 ip->i_db[nb] = dbtofsb(fs, bp->b_blkno); 96 ip->i_flag |= IN_CHANGE | IN_UPDATE; 97 if (flags & B_SYNC) 98 bwrite(bp); 99 else 100 bawrite(bp); 101 } 102 } 103 /* 104 * The first NDADDR blocks are direct blocks 105 */ 106 if (lbn < NDADDR) { 107 nb = ip->i_db[lbn]; 108 if (nb != 0 && ip->i_size >= (lbn + 1) * fs->fs_bsize) { 109 error = bread(vp, lbn, fs->fs_bsize, NOCRED, &bp); 110 if (error) { 111 brelse(bp); 112 return (error); 113 } 114 *bpp = bp; 115 return (0); 116 } 117 if (nb != 0) { 118 /* 119 * Consider need to reallocate a fragment. 120 */ 121 osize = fragroundup(fs, blkoff(fs, ip->i_size)); 122 nsize = fragroundup(fs, size); 123 if (nsize <= osize) { 124 error = bread(vp, lbn, osize, NOCRED, &bp); 125 if (error) { 126 brelse(bp); 127 return (error); 128 } 129 } else { 130 error = ffs_realloccg(ip, lbn, 131 ffs_blkpref(ip, lbn, (int)lbn, 132 &ip->i_db[0]), osize, nsize, cred, &bp); 133 if (error) 134 return (error); 135 } 136 } else { 137 if (ip->i_size < (lbn + 1) * fs->fs_bsize) 138 nsize = fragroundup(fs, size); 139 else 140 nsize = fs->fs_bsize; 141 error = ffs_alloc(ip, lbn, 142 ffs_blkpref(ip, lbn, (int)lbn, &ip->i_db[0]), 143 nsize, cred, &newb); 144 if (error) 145 return (error); 146 bp = getblk(vp, lbn, nsize, 0, 0); 147 bp->b_blkno = fsbtodb(fs, newb); 148 if (flags & B_CLRBUF) 149 clrbuf(bp); 150 } 151 ip->i_db[lbn] = dbtofsb(fs, bp->b_blkno); 152 ip->i_flag |= IN_CHANGE | IN_UPDATE; 153 *bpp = bp; 154 return (0); 155 } 156 /* 157 * Determine the number of levels of indirection. 158 */ 159 pref = 0; 160 if (error = ufs_getlbns(vp, lbn, indirs, &num)) 161 return(error); 162 #ifdef DIAGNOSTIC 163 if (num < 1) 164 panic ("ffs_balloc: ufs_bmaparray returned indirect block\n"); 165 #endif 166 /* 167 * Fetch the first indirect block allocating if necessary. 168 */ 169 --num; 170 nb = ip->i_ib[indirs[0].in_off]; 171 allocib = NULL; 172 allocblk = allociblk; 173 if (nb == 0) { 174 pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0); 175 if (error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, 176 cred, &newb)) 177 return (error); 178 nb = newb; 179 *allocblk++ = nb; 180 bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0); 181 bp->b_blkno = fsbtodb(fs, nb); 182 clrbuf(bp); 183 /* 184 * Write synchronously so that indirect blocks 185 * never point at garbage. 186 */ 187 if (error = bwrite(bp)) 188 goto fail; 189 allocib = &ip->i_ib[indirs[0].in_off]; 190 *allocib = nb; 191 ip->i_flag |= IN_CHANGE | IN_UPDATE; 192 } 193 /* 194 * Fetch through the indirect blocks, allocating as necessary. 195 */ 196 for (i = 1;;) { 197 error = bread(vp, 198 indirs[i].in_lbn, (int)fs->fs_bsize, NOCRED, &bp); 199 if (error) { 200 brelse(bp); 201 goto fail; 202 } 203 bap = (ufs_daddr_t *)bp->b_data; 204 nb = bap[indirs[i].in_off]; 205 if (i == num) 206 break; 207 i += 1; 208 if (nb != 0) { 209 brelse(bp); 210 continue; 211 } 212 if (pref == 0) 213 pref = ffs_blkpref(ip, lbn, 0, (ufs_daddr_t *)0); 214 if (error = 215 ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) { 216 brelse(bp); 217 goto fail; 218 } 219 nb = newb; 220 *allocblk++ = nb; 221 nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0); 222 nbp->b_blkno = fsbtodb(fs, nb); 223 clrbuf(nbp); 224 /* 225 * Write synchronously so that indirect blocks 226 * never point at garbage. 227 */ 228 if (error = bwrite(nbp)) { 229 brelse(bp); 230 goto fail; 231 } 232 bap[indirs[i - 1].in_off] = nb; 233 /* 234 * If required, write synchronously, otherwise use 235 * delayed write. 236 */ 237 if (flags & B_SYNC) { 238 bwrite(bp); 239 } else { 240 bdwrite(bp); 241 } 242 } 243 /* 244 * Get the data block, allocating if necessary. 245 */ 246 if (nb == 0) { 247 pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]); 248 if (error = ffs_alloc(ip, 249 lbn, pref, (int)fs->fs_bsize, cred, &newb)) { 250 brelse(bp); 251 goto fail; 252 } 253 nb = newb; 254 *allocblk++ = nb; 255 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0); 256 nbp->b_blkno = fsbtodb(fs, nb); 257 if (flags & B_CLRBUF) 258 clrbuf(nbp); 259 bap[indirs[i].in_off] = nb; 260 /* 261 * If required, write synchronously, otherwise use 262 * delayed write. 263 */ 264 if (flags & B_SYNC) { 265 bwrite(bp); 266 } else { 267 bdwrite(bp); 268 } 269 *bpp = nbp; 270 return (0); 271 } 272 brelse(bp); 273 if (flags & B_CLRBUF) { 274 error = bread(vp, lbn, (int)fs->fs_bsize, NOCRED, &nbp); 275 if (error) { 276 brelse(nbp); 277 goto fail; 278 } 279 } else { 280 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0); 281 nbp->b_blkno = fsbtodb(fs, nb); 282 } 283 *bpp = nbp; 284 return (0); 285 fail: 286 /* 287 * If we have failed part way through block allocation, we 288 * have to deallocate any indirect blocks that we have allocated. 289 */ 290 for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) { 291 ffs_blkfree(ip, *blkp, fs->fs_bsize); 292 deallocated += fs->fs_bsize; 293 } 294 if (allocib != NULL) 295 *allocib = 0; 296 if (deallocated) { 297 #ifdef QUOTA 298 /* 299 * Restore user's disk quota because allocation failed. 300 */ 301 (void) chkdq(ip, (long)-btodb(deallocated), cred, FORCE); 302 #endif 303 ip->i_blocks -= btodb(deallocated); 304 ip->i_flag |= IN_CHANGE | IN_UPDATE; 305 } 306 return (error); 307 } 308
Indexes created Tue Oct 14 06:10:07 GMT 2025