ffs_balloc.c revision 8876
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 8.4 (Berkeley) 9/23/93 34 * $Id: ffs_balloc.c,v 1.8 1995/05/28 04:32:23 davidg Exp $ 35 */ 36 37#include <sys/param.h> 38#include <sys/systm.h> 39#include <sys/buf.h> 40#include <sys/proc.h> 41#include <sys/file.h> 42#include <sys/vnode.h> 43 44#include <vm/vm.h> 45 46#include <ufs/ufs/quota.h> 47#include <ufs/ufs/inode.h> 48#include <ufs/ufs/ufs_extern.h> 49 50#include <ufs/ffs/fs.h> 51#include <ufs/ffs/ffs_extern.h> 52 53/* 54 * Balloc defines the structure of file system storage 55 * by allocating the physical blocks on a device given 56 * the inode and the logical block number in a file. 57 */ 58int 59ffs_balloc(ip, bn, size, cred, bpp, flags) 60 register struct inode *ip; 61 register daddr_t bn; 62 int size; 63 struct ucred *cred; 64 struct buf **bpp; 65 int flags; 66{ 67 register struct fs *fs; 68 register daddr_t nb; 69 struct buf *bp, *nbp; 70 struct vnode *vp = ITOV(ip); 71 struct indir indirs[NIADDR + 2]; 72 daddr_t newb, lbn, *bap, pref; 73 int osize, nsize, num, i, error; 74 75 *bpp = NULL; 76 if (bn < 0) 77 return (EFBIG); 78 fs = ip->i_fs; 79 lbn = bn; 80 81 /* 82 * If the next write will extend the file into a new block, 83 * and the file is currently composed of a fragment 84 * this fragment has to be extended to be a full block. 85 */ 86 nb = lblkno(fs, ip->i_size); 87 if (nb < NDADDR && nb < bn) { 88 osize = blksize(fs, ip, nb); 89 if (osize < fs->fs_bsize && osize > 0) { 90 error = ffs_realloccg(ip, nb, 91 ffs_blkpref(ip, nb, (int)nb, &ip->i_db[0]), 92 osize, (int)fs->fs_bsize, cred, &bp); 93 if (error) 94 return (error); 95 ip->i_size = (nb + 1) * fs->fs_bsize; 96 ip->i_db[nb] = dbtofsb(fs, bp->b_blkno); 97 ip->i_flag |= IN_CHANGE | IN_UPDATE; 98 if (flags & B_SYNC) 99 bwrite(bp); 100 else 101 bawrite(bp); 102 } 103 } 104 /* 105 * The first NDADDR blocks are direct blocks 106 */ 107 if (bn < NDADDR) { 108 nb = ip->i_db[bn]; 109 if (nb != 0 && ip->i_size >= (bn + 1) * fs->fs_bsize) { 110 error = bread(vp, bn, fs->fs_bsize, NOCRED, &bp); 111 if (error) { 112 brelse(bp); 113 return (error); 114 } 115 bp->b_blkno = fsbtodb(fs, nb); 116 *bpp = bp; 117 return (0); 118 } 119 if (nb != 0) { 120 /* 121 * Consider need to reallocate a fragment. 122 */ 123 osize = fragroundup(fs, blkoff(fs, ip->i_size)); 124 nsize = fragroundup(fs, size); 125 if (nsize <= osize) { 126 error = bread(vp, bn, osize, NOCRED, &bp); 127 if (error) { 128 brelse(bp); 129 return (error); 130 } 131 bp->b_blkno = fsbtodb(fs, nb); 132 } else { 133 error = ffs_realloccg(ip, bn, 134 ffs_blkpref(ip, bn, (int)bn, &ip->i_db[0]), 135 osize, nsize, cred, &bp); 136 if (error) 137 return (error); 138 } 139 } else { 140 if (ip->i_size < (bn + 1) * fs->fs_bsize) 141 nsize = fragroundup(fs, size); 142 else 143 nsize = fs->fs_bsize; 144 error = ffs_alloc(ip, bn, 145 ffs_blkpref(ip, bn, (int)bn, &ip->i_db[0]), 146 nsize, cred, &newb); 147 if (error) 148 return (error); 149 bp = getblk(vp, bn, nsize, 0, 0); 150 bp->b_blkno = fsbtodb(fs, newb); 151 if (flags & B_CLRBUF) 152 vfs_bio_clrbuf(bp); 153 } 154 ip->i_db[bn] = dbtofsb(fs, bp->b_blkno); 155 ip->i_flag |= IN_CHANGE | IN_UPDATE; 156 *bpp = bp; 157 return (0); 158 } 159 /* 160 * Determine the number of levels of indirection. 161 */ 162 pref = 0; 163 error = ufs_getlbns(vp, bn, indirs, &num); 164 if (error) 165 return(error); 166#ifdef DIAGNOSTIC 167 if (num < 1) 168 panic ("ffs_balloc: ufs_bmaparray returned indirect block"); 169#endif 170 /* 171 * Fetch the first indirect block allocating if necessary. 172 */ 173 --num; 174 nb = ip->i_ib[indirs[0].in_off]; 175 if (nb == 0) { 176 pref = ffs_blkpref(ip, lbn, 0, (daddr_t *)0); 177 error = ffs_alloc(ip, lbn, pref, 178 (int)fs->fs_bsize, cred, &newb); 179 if (error) 180 return (error); 181 nb = newb; 182 bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0); 183 bp->b_blkno = fsbtodb(fs, newb); 184 vfs_bio_clrbuf(bp); 185 /* 186 * Write synchronously so that indirect blocks 187 * never point at garbage. 188 */ 189 error = bwrite(bp); 190 if (error) { 191 ffs_blkfree(ip, nb, fs->fs_bsize); 192 return (error); 193 } 194 ip->i_ib[indirs[0].in_off] = newb; 195 ip->i_flag |= IN_CHANGE | IN_UPDATE; 196 } 197 /* 198 * Fetch through the indirect blocks, allocating as necessary. 199 */ 200 for (i = 1;;) { 201 error = bread(vp, 202 indirs[i].in_lbn, (int)fs->fs_bsize, NOCRED, &bp); 203 if (error) { 204 brelse(bp); 205 return (error); 206 } 207 bap = (daddr_t *)bp->b_data; 208 nb = bap[indirs[i].in_off]; 209 if (i == num) 210 break; 211 i += 1; 212 if (nb != 0) { 213 brelse(bp); 214 continue; 215 } 216 if (pref == 0) 217 pref = ffs_blkpref(ip, lbn, 0, (daddr_t *)0); 218 error = 219 ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb); 220 if (error) { 221 brelse(bp); 222 return (error); 223 } 224 nb = newb; 225 nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0); 226 nbp->b_blkno = fsbtodb(fs, nb); 227 vfs_bio_clrbuf(nbp); 228 /* 229 * Write synchronously so that indirect blocks 230 * never point at garbage. 231 */ 232 error = bwrite(nbp); 233 if (error) { 234 ffs_blkfree(ip, nb, fs->fs_bsize); 235 brelse(bp); 236 return (error); 237 } 238 bap[indirs[i - 1].in_off] = nb; 239 /* 240 * If required, write synchronously, otherwise use 241 * delayed write. 242 */ 243 if (flags & B_SYNC) { 244 bwrite(bp); 245 } else { 246 bdwrite(bp); 247 } 248 } 249 /* 250 * Get the data block, allocating if necessary. 251 */ 252 if (nb == 0) { 253 pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]); 254 error = ffs_alloc(ip, 255 lbn, pref, (int)fs->fs_bsize, cred, &newb); 256 if (error) { 257 brelse(bp); 258 return (error); 259 } 260 nb = newb; 261 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0); 262 nbp->b_blkno = fsbtodb(fs, nb); 263 if (flags & B_CLRBUF) 264 vfs_bio_clrbuf(nbp); 265 bap[indirs[i].in_off] = nb; 266 /* 267 * If required, write synchronously, otherwise use 268 * delayed write. 269 */ 270 if (flags & B_SYNC) { 271 bwrite(bp); 272 } else { 273 bdwrite(bp); 274 } 275 *bpp = nbp; 276 return (0); 277 } 278 brelse(bp); 279 if (flags & B_CLRBUF) { 280 error = bread(vp, lbn, (int)fs->fs_bsize, NOCRED, &nbp); 281 if (error) { 282 brelse(nbp); 283 return (error); 284 } 285 } else { 286 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0); 287 nbp->b_blkno = fsbtodb(fs, nb); 288 } 289 *bpp = nbp; 290 return (0); 291} 292