| File: | ufs/ext2fs/ext2fs_balloc.c |
| Warning: | line 110, column 2 Value stored to 'pref' is never read |
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| 1 | /* $OpenBSD: ext2fs_balloc.c,v 1.27 2019/07/19 00:24:31 cheloha 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)((ip)->i_vnode); |
| 61 | struct indir indirs[NIADDR3 + 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[NIADDR3 + 1]; |
| 66 | int unwindidx = -1; |
| 67 | daddr_t lbn, pref; |
| 68 | |
| 69 | *bpp = NULL((void *)0); |
| 70 | fs = ip->i_e2fsinode_u.e2fs; |
| 71 | lbn = bn; |
| 72 | |
| 73 | /* |
| 74 | * The first NDADDR blocks are direct blocks |
| 75 | */ |
| 76 | if (bn < NDADDR12) { |
| 77 | nb = letoh32(ip->i_e2fs_blocks[bn])((__uint32_t)(ip->dinode_u.e2fs_din->e2di_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_blocksdinode_u.e2fs_din->e2di_blocks[0]), |
| 93 | cred, &newb); |
| 94 | if (error) |
| 95 | return (error); |
| 96 | ip->i_e2fs_last_lblkinode_ext.e2fs.ext2fs_last_lblk = lbn; |
| 97 | ip->i_e2fs_last_blkinode_ext.e2fs.ext2fs_last_blk = newb; |
| 98 | ip->i_e2fs_blocksdinode_u.e2fs_din->e2di_blocks[bn] = htole32(newb)((__uint32_t)(newb)); |
| 99 | ip->i_flag |= IN_CHANGE0x0002 | IN_UPDATE0x0004; |
| 100 | bp = getblk(vp, bn, fs->e2fs_bsize, 0, INFSLP0xffffffffffffffffULL); |
| 101 | bp->b_blkno = fsbtodb(fs, newb)((newb) << (fs)->e2fs_fsbtodb); |
| 102 | if (flags & B_CLRBUF0x01) |
| 103 | clrbuf(bp){ __builtin_bzero(((bp)->b_data), ((bp)->b_bcount)); (bp )->b_resid = 0; }; |
| 104 | *bpp = bp; |
| 105 | return (0); |
| 106 | } |
| 107 | /* |
| 108 | * Determine the number of levels of indirection. |
| 109 | */ |
| 110 | pref = 0; |
Value stored to 'pref' is never read | |
| 111 | if ((error = ufs_getlbns(vp, bn, indirs, &num)) != 0) |
| 112 | return(error); |
| 113 | #ifdef DIAGNOSTIC1 |
| 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])((__uint32_t)(ip->dinode_u.e2fs_din->e2di_blocks[12 + indirs [0].in_off])); |
| 122 | allocib = NULL((void *)0); |
| 123 | allocblk = allociblk; |
| 124 | if (nb == 0) { |
| 125 | pref = ext2fs_blkpref(ip, lbn, 0, NULL((void *)0)); |
| 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_blkinode_ext.e2fs.ext2fs_last_blk = newb; |
| 132 | bp = getblk(vp, indirs[1].in_lbn, fs->e2fs_bsize, 0, INFSLP0xffffffffffffffffULL); |
| 133 | bp->b_blkno = fsbtodb(fs, newb)((newb) << (fs)->e2fs_fsbtodb); |
| 134 | clrbuf(bp){ __builtin_bzero(((bp)->b_data), ((bp)->b_bcount)); (bp )->b_resid = 0; }; |
| 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_blocksdinode_u.e2fs_din->e2di_blocks[NDADDR12 + indirs[0].in_off]; |
| 143 | *allocib = htole32(newb)((__uint32_t)(newb)); |
| 144 | ip->i_flag |= IN_CHANGE0x0002 | IN_UPDATE0x0004; |
| 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])((__uint32_t)(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((void *)0)); |
| 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_blkinode_ext.e2fs.ext2fs_last_blk = newb; |
| 173 | nbp = getblk(vp, indirs[i].in_lbn, fs->e2fs_bsize, 0, INFSLP0xffffffffffffffffULL); |
| 174 | nbp->b_blkno = fsbtodb(fs, nb)((nb) << (fs)->e2fs_fsbtodb); |
| 175 | clrbuf(nbp){ __builtin_bzero(((nbp)->b_data), ((nbp)->b_bcount)); ( nbp)->b_resid = 0; }; |
| 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)((__uint32_t)(nb)); |
| 187 | /* |
| 188 | * If required, write synchronously, otherwise use |
| 189 | * delayed write. |
| 190 | */ |
| 191 | if (flags & B_SYNC0x02) { |
| 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_lblkinode_ext.e2fs.ext2fs_last_lblk = lbn; |
| 210 | ip->i_e2fs_last_blkinode_ext.e2fs.ext2fs_last_blk = newb; |
| 211 | bap[indirs[num].in_off] = htole32(nb)((__uint32_t)(nb)); |
| 212 | /* |
| 213 | * If required, write synchronously, otherwise use |
| 214 | * delayed write. |
| 215 | */ |
| 216 | if (flags & B_SYNC0x02) { |
| 217 | bwrite(bp); |
| 218 | } else { |
| 219 | bdwrite(bp); |
| 220 | } |
| 221 | nbp = getblk(vp, lbn, fs->e2fs_bsize, 0, INFSLP0xffffffffffffffffULL); |
| 222 | nbp->b_blkno = fsbtodb(fs, nb)((nb) << (fs)->e2fs_fsbtodb); |
| 223 | if (flags & B_CLRBUF0x01) |
| 224 | clrbuf(nbp){ __builtin_bzero(((nbp)->b_data), ((nbp)->b_bcount)); ( nbp)->b_resid = 0; }; |
| 225 | *bpp = nbp; |
| 226 | return (0); |
| 227 | } |
| 228 | brelse(bp); |
| 229 | if (flags & B_CLRBUF0x01) { |
| 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, INFSLP0xffffffffffffffffULL); |
| 237 | nbp->b_blkno = fsbtodb(fs, nb)((nb) << (fs)->e2fs_fsbtodb); |
| 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_SYNC0x02) |
| 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, INFSLP0xffffffffffffffffULL); |
| 273 | bp->b_flags |= B_INVAL0x00000800; |
| 274 | brelse(bp); |
| 275 | } |
| 276 | } |
| 277 | if (deallocated) { |
| 278 | ip->i_e2fs_nblockdinode_u.e2fs_din->e2di_nblock -= btodb(deallocated)((deallocated) >> 9); |
| 279 | ip->i_e2fs_flagsdinode_u.e2fs_din->e2di_flags |= IN_CHANGE0x0002 | IN_UPDATE0x0004; |
| 280 | } |
| 281 | return error; |
| 282 | } |