1 /* 2 * Copyright (c) 1986, 1989, 1991 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)lfs_inode.c 7.56 (Berkeley) 02/04/92 8 */ 9 10 #include <sys/param.h> 11 #include <sys/systm.h> 12 #include <sys/mount.h> 13 #include <sys/proc.h> 14 #include <sys/file.h> 15 #include <sys/buf.h> 16 #include <sys/vnode.h> 17 #include <sys/kernel.h> 18 #include <sys/malloc.h> 19 20 #include <ufs/ufs/quota.h> 21 #include <ufs/ufs/inode.h> 22 #include <ufs/ufs/ufsmount.h> 23 #include <ufs/ufs/ufs_extern.h> 24 25 #include <ufs/lfs/lfs.h> 26 #include <ufs/lfs/lfs_extern.h> 27 28 int 29 lfs_init() 30 { 31 #ifdef VERBOSE 32 printf("lfs_init\n"); 33 #endif 34 return (ufs_init()); 35 } 36 37 /* 38 * Look up an LFS dinode number to find its incore vnode. If not already 39 * in core, read it in from the specified device. Return the inode locked. 40 * Detection and handling of mount points must be done by the calling routine. 41 */ 42 int 43 lfs_vget(mntp, ino, vpp) 44 struct mount *mntp; 45 ino_t ino; 46 struct vnode **vpp; 47 { 48 register struct lfs *fs; 49 register struct inode *ip; 50 struct buf *bp; 51 struct ifile *ifp; 52 struct vnode *vp; 53 struct ufsmount *ump; 54 daddr_t daddr; 55 dev_t dev; 56 int error; 57 58 #ifdef VERBOSE 59 printf("lfs_vget\n"); 60 #endif 61 ump = VFSTOUFS(mntp); 62 dev = ump->um_dev; 63 if ((*vpp = ufs_ihashget(dev, ino)) != NULL) 64 return (0); 65 66 /* Translate the inode number to a disk address. */ 67 fs = ump->um_lfs; 68 if (ino == LFS_IFILE_INUM) 69 daddr = fs->lfs_idaddr; 70 else { 71 LFS_IENTRY(ifp, fs, ino, bp); 72 daddr = ifp->if_daddr; 73 brelse(bp); 74 if (daddr == LFS_UNUSED_DADDR) 75 return (ENOENT); 76 } 77 78 /* Allocate new vnode/inode. */ 79 if (error = lfs_vcreate(mntp, ino, &vp)) { 80 *vpp = NULL; 81 return (error); 82 } 83 84 /* 85 * Put it onto its hash chain and lock it so that other requests for 86 * this inode will block if they arrive while we are sleeping waiting 87 * for old data structures to be purged or for the contents of the 88 * disk portion of this inode to be read. 89 */ 90 ip = VTOI(vp); 91 ufs_ihashins(ip); 92 93 /* 94 * XXX 95 * This may not need to be here, logically it should go down with 96 * the i_devvp initialization. 97 * Ask Kirk. 98 */ 99 ip->i_lfs = ump->um_lfs; 100 101 /* Read in the disk contents for the inode, copy into the inode. */ 102 if (error = 103 bread(ump->um_devvp, daddr, (int)fs->lfs_bsize, NOCRED, &bp)) { 104 /* 105 * The inode does not contain anything useful, so it 106 * would be misleading to leave it on its hash chain. 107 * Iput() will return it to the free list. 108 */ 109 remque(ip); 110 ip->i_forw = ip; 111 ip->i_back = ip; 112 113 /* Unlock and discard unneeded inode. */ 114 ufs_iput(ip); 115 brelse(bp); 116 *vpp = NULL; 117 return (error); 118 } 119 ip->i_din = *lfs_ifind(fs, ino, bp->b_un.b_dino); 120 brelse(bp); 121 122 /* 123 * Initialize the vnode from the inode, check for aliases. In all 124 * cases re-init ip, the underlying vnode/inode may have changed. 125 */ 126 if (error = ufs_vinit(mntp, &lfs_specops, LFS_FIFOOPS, &vp)) { 127 ufs_iput(ip); 128 *vpp = NULL; 129 return (error); 130 } 131 /* 132 * Finish inode initialization now that aliasing has been resolved. 133 */ 134 ip->i_devvp = ump->um_devvp; 135 VREF(ip->i_devvp); 136 *vpp = vp; 137 return (0); 138 } 139 140 int 141 lfs_update(vp, ta, tm, waitfor) 142 register struct vnode *vp; 143 struct timeval *ta, *tm; 144 int waitfor; 145 { 146 struct inode *ip; 147 148 #ifdef VERBOSE 149 printf("lfs_update\n"); 150 #endif 151 if (vp->v_mount->mnt_flag & MNT_RDONLY) 152 return (0); 153 ip = VTOI(vp); 154 if ((ip->i_flag & (IUPD|IACC|ICHG|IMOD)) == 0) 155 return (0); 156 if (ip->i_flag&IACC) 157 ip->i_atime = ta->tv_sec; 158 if (ip->i_flag&IUPD) { 159 ip->i_mtime = tm->tv_sec; 160 INCRQUAD((ip)->i_modrev); 161 } 162 if (ip->i_flag&ICHG) 163 ip->i_ctime = time.tv_sec; 164 ip->i_flag &= ~(IUPD|IACC|ICHG|IMOD); 165 166 /* Push back the vnode and any dirty blocks it may have. */ 167 return (waitfor ? lfs_vflush(vp) : 0); 168 } 169 170 /* Update segment usage information when removing a block. */ 171 #define UPDATE_SEGUSE \ 172 if (lastseg != -1) { \ 173 LFS_SEGENTRY(sup, fs, lastseg, sup_bp); \ 174 sup->su_nbytes -= fs->lfs_bsize * num; \ 175 LFS_UBWRITE(sup_bp); \ 176 blocksreleased += num; \ 177 } 178 179 #define SEGDEC { \ 180 if (daddr != UNASSIGNED) { \ 181 if (lastseg != (seg = datosn(fs, daddr))) { \ 182 UPDATE_SEGUSE; \ 183 num = 1; \ 184 lastseg = seg; \ 185 } else \ 186 ++num; \ 187 } \ 188 } 189 190 /* 191 * Truncate the inode ip to at most length size. Update segment usage 192 * table information. 193 */ 194 /* ARGSUSED */ 195 int 196 lfs_truncate(vp, length, flags) 197 struct vnode *vp; 198 u_long length; 199 int flags; 200 { 201 register INDIR *ap; 202 register int i; 203 register daddr_t *daddrp; 204 struct buf *bp, *sup_bp; 205 struct ifile *ifp; 206 struct inode *ip; 207 struct lfs *fs; 208 INDIR a[NIADDR + 2], a_end[NIADDR + 2]; 209 SEGUSE *sup; 210 daddr_t daddr, lastblock, lbn, olastblock; 211 off_t off; 212 long blocksreleased; 213 int error, depth, lastseg, num, offset, seg, size; 214 215 #ifdef VERBOSE 216 printf("lfs_truncate\n"); 217 #endif 218 vnode_pager_setsize(vp, length); 219 220 ip = VTOI(vp); 221 fs = ip->i_lfs; 222 223 /* If truncating the file to 0, update the version number. */ 224 if (length == 0) { 225 LFS_IENTRY(ifp, fs, ip->i_number, bp); 226 ++ifp->if_version; 227 LFS_UBWRITE(bp); 228 } 229 230 /* If length is larger than the file, just update the times. */ 231 if (ip->i_size <= length) { 232 ip->i_flag |= ICHG|IUPD; 233 return (lfs_update(vp, &time, &time, 1)); 234 } 235 236 /* 237 * Calculate index into inode's block list of last direct and indirect 238 * blocks (if any) which we want to keep. Lastblock is 0 when the 239 * file is truncated to 0. 240 */ 241 lastblock = lblkno(fs, length + fs->lfs_bsize - 1); 242 olastblock = lblkno(fs, ip->i_size + fs->lfs_bsize - 1) - 1; 243 244 /* 245 * Update the size of the file. If the file is not being truncated to 246 * a block boundry, the contents of the partial block following the end 247 * of the file must be zero'ed in case it ever become accessable again 248 * because of subsequent file growth. 249 */ 250 offset = blkoff(fs, length); 251 if (offset == 0) 252 ip->i_size = length; 253 else { 254 lbn = lblkno(fs, length); 255 #ifdef QUOTA 256 if (error = getinoquota(ip)) 257 return (error); 258 #endif 259 if (error = bread(vp, lbn, fs->lfs_bsize, NOCRED, &bp)) 260 return (error); 261 ip->i_size = length; 262 size = blksize(fs); 263 (void)vnode_pager_uncache(vp); 264 bzero(bp->b_un.b_addr + offset, (unsigned)(size - offset)); 265 allocbuf(bp, size); 266 LFS_UBWRITE(bp); 267 } 268 /* 269 * Modify sup->su_nbyte counters for each deleted block; keep track 270 * of number of blocks removed for ip->i_blocks. 271 */ 272 blocksreleased = 0; 273 num = 0; 274 lastseg = -1; 275 276 for (lbn = olastblock; lbn >= lastblock;) { 277 lfs_bmaparray(vp, lbn, &daddr, a, &depth); 278 if (lbn == olastblock) 279 for (i = NIADDR + 2; i--;) 280 a_end[i] = a[i]; 281 switch (depth) { 282 case 0: /* Direct block. */ 283 daddr = ip->i_db[lbn]; 284 SEGDEC; 285 ip->i_db[lbn] = 0; 286 --lbn; 287 break; 288 #ifdef DIAGNOSTIC 289 case 1: /* An indirect block. */ 290 panic("lfs_truncate: lfs_bmaparray returned depth 1"); 291 /* NOTREACHED */ 292 #endif 293 default: /* Chain of indirect blocks. */ 294 ap = a + --depth; 295 if (ap->in_off > 0 && lbn != lastblock) { 296 lbn -= ap->in_off < lbn - lastblock ? 297 ap->in_off : lbn - lastblock; 298 break; 299 } 300 for (; depth && (ap->in_off == 0 || lbn == lastblock); 301 --ap, --depth) { 302 /* 303 * XXX 304 * The indirect block may not yet exist, so 305 * bread will create one just so we can free 306 * it. 307 */ 308 if (bread(vp, 309 ap->in_lbn, fs->lfs_bsize, NOCRED, &bp)) 310 panic("lfs_truncate: bread bno %d", 311 ap->in_lbn); 312 daddrp = bp->b_un.b_daddr + ap->in_off; 313 for (i = ap->in_off; 314 i++ <= a_end[depth].in_off;) { 315 daddr = *daddrp++; 316 SEGDEC; 317 } 318 a_end[depth].in_off=NINDIR(fs)-1; 319 if (ap->in_off > 0 && lbn == lastblock) { 320 bzero(bp->b_un.b_daddr + ap->in_off, 321 fs->lfs_bsize - 322 ap->in_off * sizeof(daddr_t)); 323 LFS_UBWRITE(bp); 324 } else 325 brelse (bp); 326 } 327 if (a[1].in_off == 0) { 328 off = a[0].in_off; 329 daddr = ip->i_ib[off]; 330 SEGDEC; 331 ip->i_ib[off] = 0; 332 } 333 if (lbn == lastblock) 334 --lbn; 335 else { 336 lbn -= NINDIR(fs); 337 if (lbn < lastblock) 338 lbn = lastblock; 339 } 340 } 341 } 342 UPDATE_SEGUSE; 343 ip->i_blocks -= blocksreleased; 344 /* 345 * XXX 346 * Currently, we don't know when we allocate an indirect block, so 347 * ip->i_blocks isn't getting incremented appropriately. As a result, 348 * when we delete any indirect blocks, we get a bad number here. 349 */ 350 if (ip->i_blocks < 0) 351 ip->i_blocks = 0; 352 ip->i_flag |= ICHG|IUPD; 353 (void)vinvalbuf(vp, length > 0); 354 error = lfs_update(vp, &time, &time, MNT_WAIT); 355 return (0); 356 } 357