ffs_balloc.c revision 1541
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 */ 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 */ 57ffs_balloc(ip, bn, size, cred, bpp, flags) 58 register struct inode *ip; 59 register daddr_t bn; 60 int size; 61 struct ucred *cred; 62 struct buf **bpp; 63 int flags; 64{ 65 register struct fs *fs; 66 register daddr_t nb; 67 struct buf *bp, *nbp; 68 struct vnode *vp = ITOV(ip); 69 struct indir indirs[NIADDR + 2]; 70 daddr_t newb, lbn, *bap, pref; 71 int osize, nsize, num, i, error; 72 73 *bpp = NULL; 74 if (bn < 0) 75 return (EFBIG); 76 fs = ip->i_fs; 77 lbn = bn; 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 < bn) { 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 (bn < NDADDR) { 107 nb = ip->i_db[bn]; 108 if (nb != 0 && ip->i_size >= (bn + 1) * fs->fs_bsize) { 109 error = bread(vp, bn, 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, bn, osize, NOCRED, &bp); 125 if (error) { 126 brelse(bp); 127 return (error); 128 } 129 } else { 130 error = ffs_realloccg(ip, bn, 131 ffs_blkpref(ip, bn, (int)bn, &ip->i_db[0]), 132 osize, nsize, cred, &bp); 133 if (error) 134 return (error); 135 } 136 } else { 137 if (ip->i_size < (bn + 1) * fs->fs_bsize) 138 nsize = fragroundup(fs, size); 139 else 140 nsize = fs->fs_bsize; 141 error = ffs_alloc(ip, bn, 142 ffs_blkpref(ip, bn, (int)bn, &ip->i_db[0]), 143 nsize, cred, &newb); 144 if (error) 145 return (error); 146 bp = getblk(vp, bn, nsize, 0, 0); 147 bp->b_blkno = fsbtodb(fs, newb); 148 if (flags & B_CLRBUF) 149 clrbuf(bp); 150 } 151 ip->i_db[bn] = 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, bn, 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 if (nb == 0) { 172 pref = ffs_blkpref(ip, lbn, 0, (daddr_t *)0); 173 if (error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, 174 cred, &newb)) 175 return (error); 176 nb = newb; 177 bp = getblk(vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0); 178 bp->b_blkno = fsbtodb(fs, newb); 179 clrbuf(bp); 180 /* 181 * Write synchronously so that indirect blocks 182 * never point at garbage. 183 */ 184 if (error = bwrite(bp)) { 185 ffs_blkfree(ip, nb, fs->fs_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->fs_bsize, NOCRED, &bp); 197 if (error) { 198 brelse(bp); 199 return (error); 200 } 201 bap = (daddr_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 brelse(bp); 208 continue; 209 } 210 if (pref == 0) 211 pref = ffs_blkpref(ip, lbn, 0, (daddr_t *)0); 212 if (error = 213 ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, cred, &newb)) { 214 brelse(bp); 215 return (error); 216 } 217 nb = newb; 218 nbp = getblk(vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0); 219 nbp->b_blkno = fsbtodb(fs, nb); 220 clrbuf(nbp); 221 /* 222 * Write synchronously so that indirect blocks 223 * never point at garbage. 224 */ 225 if (error = bwrite(nbp)) { 226 ffs_blkfree(ip, nb, fs->fs_bsize); 227 brelse(bp); 228 return (error); 229 } 230 bap[indirs[i - 1].in_off] = nb; 231 /* 232 * If required, write synchronously, otherwise use 233 * delayed write. 234 */ 235 if (flags & B_SYNC) { 236 bwrite(bp); 237 } else { 238 bdwrite(bp); 239 } 240 } 241 /* 242 * Get the data block, allocating if necessary. 243 */ 244 if (nb == 0) { 245 pref = ffs_blkpref(ip, lbn, indirs[i].in_off, &bap[0]); 246 if (error = ffs_alloc(ip, 247 lbn, pref, (int)fs->fs_bsize, cred, &newb)) { 248 brelse(bp); 249 return (error); 250 } 251 nb = newb; 252 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0); 253 nbp->b_blkno = fsbtodb(fs, nb); 254 if (flags & B_CLRBUF) 255 clrbuf(nbp); 256 bap[indirs[i].in_off] = nb; 257 /* 258 * If required, write synchronously, otherwise use 259 * delayed write. 260 */ 261 if (flags & B_SYNC) { 262 bwrite(bp); 263 } else { 264 bdwrite(bp); 265 } 266 *bpp = nbp; 267 return (0); 268 } 269 brelse(bp); 270 if (flags & B_CLRBUF) { 271 error = bread(vp, lbn, (int)fs->fs_bsize, NOCRED, &nbp); 272 if (error) { 273 brelse(nbp); 274 return (error); 275 } 276 } else { 277 nbp = getblk(vp, lbn, fs->fs_bsize, 0, 0); 278 nbp->b_blkno = fsbtodb(fs, nb); 279 } 280 *bpp = nbp; 281 return (0); 282} 283