1 /* $OpenBSD: ext2fs_balloc.c,v 1.26 2016/06/03 18:00:10 natano Exp $ */ 2 /* $NetBSD: ext2fs_balloc.c,v 1.10 2001/07/04 21:16:01 chs Exp $ */ 3 4 /* 5 * Copyright (c) 1997 Manuel Bouyer. 6 * Copyright (c) 1982, 1986, 1989, 1993 7 * The Regents of the University of California. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. 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 * Modified for ext2fs by Manuel Bouyer. 35 */ 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/buf.h> 40 #include <sys/vnode.h> 41 42 #include <ufs/ufs/quota.h> 43 #include <ufs/ufs/inode.h> 44 #include <ufs/ufs/ufs_extern.h> 45 46 #include <ufs/ext2fs/ext2fs.h> 47 #include <ufs/ext2fs/ext2fs_extern.h> 48 49 /* 50 * Balloc defines the structure of file system storage 51 * by allocating the physical blocks on a device given 52 * the inode and the logical block number in a file. 53 */ 54 int 55 ext2fs_buf_alloc(struct inode *ip, u_int32_t bn, int size, struct ucred *cred, 56 struct buf **bpp, int flags) 57 { 58 struct m_ext2fs *fs; 59 struct buf *bp, *nbp; 60 struct vnode *vp = ITOV(ip); 61 struct indir indirs[NIADDR + 2]; 62 u_int32_t nb, newb, *bap; 63 int num, i, error; 64 u_int deallocated; 65 u_int32_t *allocib, *blkp, *allocblk, allociblk[NIADDR + 1]; 66 int unwindidx = -1; 67 daddr_t lbn, pref; 68 69 *bpp = NULL; 70 fs = ip->i_e2fs; 71 lbn = bn; 72 73 /* 74 * The first NDADDR blocks are direct blocks 75 */ 76 if (bn < NDADDR) { 77 nb = letoh32(ip->i_e2fs_blocks[bn]); 78 if (nb != 0) { 79 error = bread(vp, bn, fs->e2fs_bsize, &bp); 80 if (error) { 81 brelse(bp); 82 return (error); 83 } 84 *bpp = bp; 85 return (0); 86 } 87 88 /* 89 * allocate a new direct block. 90 */ 91 error = ext2fs_alloc(ip, bn, 92 ext2fs_blkpref(ip, bn, (int)bn, &ip->i_e2fs_blocks[0]), 93 cred, &newb); 94 if (error) 95 return (error); 96 ip->i_e2fs_last_lblk = lbn; 97 ip->i_e2fs_last_blk = newb; 98 ip->i_e2fs_blocks[bn] = htole32(newb); 99 ip->i_flag |= IN_CHANGE | IN_UPDATE; 100 bp = getblk(vp, bn, fs->e2fs_bsize, 0, 0); 101 bp->b_blkno = fsbtodb(fs, newb); 102 if (flags & B_CLRBUF) 103 clrbuf(bp); 104 *bpp = bp; 105 return (0); 106 } 107 /* 108 * Determine the number of levels of indirection. 109 */ 110 pref = 0; 111 if ((error = ufs_getlbns(vp, bn, indirs, &num)) != 0) 112 return(error); 113 #ifdef DIAGNOSTIC 114 if (num < 1) 115 panic ("ext2fs_balloc: ufs_getlbns returned indirect block"); 116 #endif 117 /* 118 * Fetch the first indirect block allocating if necessary. 119 */ 120 --num; 121 nb = letoh32(ip->i_e2fs_blocks[NDADDR + indirs[0].in_off]); 122 allocib = NULL; 123 allocblk = allociblk; 124 if (nb == 0) { 125 pref = ext2fs_blkpref(ip, lbn, 0, NULL); 126 error = ext2fs_alloc(ip, lbn, pref, cred, &newb); 127 if (error) 128 return (error); 129 nb = newb; 130 *allocblk++ = nb; 131 ip->i_e2fs_last_blk = newb; 132 bp = getblk(vp, indirs[1].in_lbn, fs->e2fs_bsize, 0, 0); 133 bp->b_blkno = fsbtodb(fs, newb); 134 clrbuf(bp); 135 /* 136 * Write synchronously so that indirect blocks 137 * never point at garbage. 138 */ 139 if ((error = bwrite(bp)) != 0) 140 goto fail; 141 unwindidx = 0; 142 allocib = &ip->i_e2fs_blocks[NDADDR + indirs[0].in_off]; 143 *allocib = htole32(newb); 144 ip->i_flag |= IN_CHANGE | IN_UPDATE; 145 } 146 /* 147 * Fetch through the indirect blocks, allocating as necessary. 148 */ 149 for (i = 1;;) { 150 error = bread(vp, indirs[i].in_lbn, (int)fs->e2fs_bsize, &bp); 151 if (error) { 152 brelse(bp); 153 goto fail; 154 } 155 bap = (u_int32_t *)bp->b_data; 156 nb = letoh32(bap[indirs[i].in_off]); 157 if (i == num) 158 break; 159 i++; 160 if (nb != 0) { 161 brelse(bp); 162 continue; 163 } 164 pref = ext2fs_blkpref(ip, lbn, 0, NULL); 165 error = ext2fs_alloc(ip, lbn, pref, cred, &newb); 166 if (error) { 167 brelse(bp); 168 goto fail; 169 } 170 nb = newb; 171 *allocblk++ = nb; 172 ip->i_e2fs_last_blk = newb; 173 nbp = getblk(vp, indirs[i].in_lbn, fs->e2fs_bsize, 0, 0); 174 nbp->b_blkno = fsbtodb(fs, nb); 175 clrbuf(nbp); 176 /* 177 * Write synchronously so that indirect blocks 178 * never point at garbage. 179 */ 180 if ((error = bwrite(nbp)) != 0) { 181 brelse(bp); 182 goto fail; 183 } 184 if (unwindidx < 0) 185 unwindidx = i - 1; 186 bap[indirs[i - 1].in_off] = htole32(nb); 187 /* 188 * If required, write synchronously, otherwise use 189 * delayed write. 190 */ 191 if (flags & B_SYNC) { 192 bwrite(bp); 193 } else { 194 bdwrite(bp); 195 } 196 } 197 /* 198 * Get the data block, allocating if necessary. 199 */ 200 if (nb == 0) { 201 pref = ext2fs_blkpref(ip, lbn, indirs[num].in_off, bap); 202 error = ext2fs_alloc(ip, lbn, pref, cred, &newb); 203 if (error) { 204 brelse(bp); 205 goto fail; 206 } 207 nb = newb; 208 *allocblk++ = nb; 209 ip->i_e2fs_last_lblk = lbn; 210 ip->i_e2fs_last_blk = newb; 211 bap[indirs[num].in_off] = htole32(nb); 212 /* 213 * If required, write synchronously, otherwise use 214 * delayed write. 215 */ 216 if (flags & B_SYNC) { 217 bwrite(bp); 218 } else { 219 bdwrite(bp); 220 } 221 nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0); 222 nbp->b_blkno = fsbtodb(fs, nb); 223 if (flags & B_CLRBUF) 224 clrbuf(nbp); 225 *bpp = nbp; 226 return (0); 227 } 228 brelse(bp); 229 if (flags & B_CLRBUF) { 230 error = bread(vp, lbn, (int)fs->e2fs_bsize, &nbp); 231 if (error) { 232 brelse(nbp); 233 goto fail; 234 } 235 } else { 236 nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, 0); 237 nbp->b_blkno = fsbtodb(fs, nb); 238 } 239 240 *bpp = nbp; 241 return (0); 242 fail: 243 /* 244 * If we have failed part way through block allocation, we 245 * have to deallocate any indirect blocks that we have allocated. 246 */ 247 for (deallocated = 0, blkp = allociblk; blkp < allocblk; blkp++) { 248 ext2fs_blkfree(ip, *blkp); 249 deallocated += fs->e2fs_bsize; 250 } 251 if (unwindidx >= 0) { 252 if (unwindidx == 0) { 253 *allocib = 0; 254 } else { 255 int r; 256 257 r = bread(vp, indirs[unwindidx].in_lbn, 258 (int)fs->e2fs_bsize, &bp); 259 if (r) { 260 panic("Could not unwind indirect block, error %d", r); 261 } else { 262 bap = (u_int32_t *)bp->b_data; 263 bap[indirs[unwindidx].in_off] = 0; 264 if (flags & B_SYNC) 265 bwrite(bp); 266 else 267 bdwrite(bp); 268 } 269 } 270 for (i = unwindidx + 1; i <= num; i++) { 271 bp = getblk(vp, indirs[i].in_lbn, (int)fs->e2fs_bsize, 272 0, 0); 273 bp->b_flags |= B_INVAL; 274 brelse(bp); 275 } 276 } 277 if (deallocated) { 278 ip->i_e2fs_nblock -= btodb(deallocated); 279 ip->i_e2fs_flags |= IN_CHANGE | IN_UPDATE; 280 } 281 return error; 282 } 283