1 /* 2 * Copyright (c) 1982, 1986, 1989 Regents of the University of California. 3 * All rights reserved. 4 * 5 * %sccs.include.redist.c% 6 * 7 * @(#)ffs_inode.c 7.41 (Berkeley) 11/01/91 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/ffs/fs.h> 26 #include <ufs/ffs/ffs_extern.h> 27 28 static int ffs_indirtrunc __P((struct inode *, daddr_t, daddr_t, int, long *)); 29 30 extern u_long nextgennumber; 31 32 int 33 ffs_init() 34 { 35 return (ufs_init()); 36 } 37 38 /* 39 * Look up a UFS dinode number to find its incore vnode. 40 * If it is not in core, read it in from the specified device. 41 * If it is in core, wait for the lock bit to clear, then 42 * return the inode locked. Detection and handling of mount 43 * points must be done by the calling routine. 44 */ 45 ffs_iget(pip, ino, ipp) 46 struct inode *pip; 47 ino_t ino; 48 struct inode **ipp; 49 { 50 extern struct vnodeops ffs_vnodeops; 51 register struct fs *fs; 52 register struct inode *ip; 53 struct buf *bp; 54 struct dinode *dp; 55 struct mount *mntp; 56 struct vnode *vp; 57 union ihead *ih; 58 dev_t dev; 59 int i, error; 60 61 mntp = ITOV(pip)->v_mount; 62 fs = VFSTOUFS(mntp)->um_fs; 63 if (ino < ROOTINO || ino >= fs->fs_ncg * fs->fs_ipg) 64 return (EINVAL); 65 66 dev = pip->i_dev; 67 if ((*ipp = ufs_ihashget(dev, ino)) != NULL) 68 return (0); 69 70 /* Allocate a new vnode/inode. */ 71 if (error = getnewvnode(VT_UFS, mntp, &ffs_vnodeops, &vp)) { 72 *ipp = NULL; 73 return (error); 74 } 75 ip = VTOI(vp); 76 ip->i_vnode = vp; 77 ip->i_flag = 0; 78 ip->i_devvp = 0; 79 ip->i_mode = 0; 80 ip->i_diroff = 0; 81 ip->i_lockf = 0; 82 #ifdef QUOTA 83 for (i = 0; i < MAXQUOTAS; i++) 84 ip->i_dquot[i] = NODQUOT; 85 #endif 86 /* 87 * Put it onto its hash chain and lock it so that other requests for 88 * this inode will block if they arrive while we are sleeping waiting 89 * for old data structures to be purged or for the contents of the 90 * disk portion of this inode to be read. 91 */ 92 ip->i_dev = dev; 93 ip->i_number = ino; 94 ip->i_fs = fs; /* XXX KIRK?? */ 95 ip->i_devvp = VFSTOUFS(mntp)->um_devvp; 96 ufs_ihashins(ip); 97 98 /* Read in the disk contents for the inode, copy into the inode. */ 99 if (error = bread(VFSTOUFS(mntp)->um_devvp, fsbtodb(fs, itod(fs, ino)), 100 (int)fs->fs_bsize, NOCRED, &bp)) { 101 /* 102 * The inode does not contain anything useful, so it would 103 * be misleading to leave it on its hash chain. Iput() will 104 * return it to the free list. 105 */ 106 remque(ip); 107 ip->i_forw = ip; 108 ip->i_back = ip; 109 110 /* Unlock and discard unneeded inode. */ 111 ufs_iput(ip); 112 brelse(bp); 113 *ipp = NULL; 114 return (error); 115 } 116 dp = bp->b_un.b_dino; 117 dp += itoo(fs, ino); 118 ip->i_din = *dp; 119 brelse(bp); 120 121 /* 122 * Initialize the vnode from the inode, check for aliases. In all 123 * cases re-init ip, the underlying vnode/inode may have changed. 124 */ 125 if (error = ufs_vinit(mntp, &vp)) { 126 ufs_iput(ip); 127 *ipp = NULL; 128 return (error); 129 } 130 ip = VTOI(vp); 131 132 /* 133 * Set up a generation number for this inode if it does not 134 * already have one. This should only happen on old filesystems. 135 */ 136 if (ip->i_gen == 0) { 137 if (++nextgennumber < (u_long)time.tv_sec) 138 nextgennumber = time.tv_sec; 139 ip->i_gen = nextgennumber; 140 if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) 141 ip->i_flag |= IMOD; 142 } 143 *ipp = ip; 144 return (0); 145 } 146 147 /* 148 * Update the access, modified, and inode change times as specified 149 * by the IACC, IMOD, and ICHG flags respectively. The IUPD flag 150 * is used to specify that the inode needs to be updated but that 151 * the times have already been set. The access and modified times 152 * are taken from the second and third parameters; the inode change 153 * time is always taken from the current time. If waitfor is set, 154 * then wait for the disk write of the inode to complete. 155 */ 156 int 157 ffs_iupdat(ip, ta, tm, waitfor) 158 register struct inode *ip; 159 struct timeval *ta, *tm; 160 int waitfor; 161 { 162 struct buf *bp; 163 struct vnode *vp = ITOV(ip); 164 struct dinode *dp; 165 register struct fs *fs; 166 int error; 167 168 fs = ip->i_fs; 169 if ((ip->i_flag & (IUPD|IACC|ICHG|IMOD)) == 0) 170 return (0); 171 if (vp->v_mount->mnt_flag & MNT_RDONLY) 172 return (0); 173 error = bread(ip->i_devvp, fsbtodb(fs, itod(fs, ip->i_number)), 174 (int)fs->fs_bsize, NOCRED, &bp); 175 if (error) { 176 brelse(bp); 177 return (error); 178 } 179 if (ip->i_flag&IACC) 180 ip->i_atime = ta->tv_sec; 181 if (ip->i_flag&IUPD) 182 ip->i_mtime = tm->tv_sec; 183 if (ip->i_flag&ICHG) 184 ip->i_ctime = time.tv_sec; 185 ip->i_flag &= ~(IUPD|IACC|ICHG|IMOD); 186 dp = bp->b_un.b_dino + itoo(fs, ip->i_number); 187 *dp = ip->i_din; 188 if (waitfor) { 189 return (bwrite(bp)); 190 } else { 191 bdwrite(bp); 192 return (0); 193 } 194 } 195 196 #define SINGLE 0 /* index of single indirect block */ 197 #define DOUBLE 1 /* index of double indirect block */ 198 #define TRIPLE 2 /* index of triple indirect block */ 199 /* 200 * Truncate the inode ip to at most length size. Free affected disk 201 * blocks -- the blocks of the file are removed in reverse order. 202 * 203 * NB: triple indirect blocks are untested. 204 */ 205 ffs_itrunc(oip, length, flags) 206 register struct inode *oip; 207 u_long length; 208 int flags; 209 { 210 register daddr_t lastblock; 211 daddr_t bn, lbn, lastiblock[NIADDR]; 212 register struct fs *fs; 213 register struct inode *ip; 214 struct buf *bp; 215 int offset, osize, size, level; 216 long count, nblocks, blocksreleased = 0; 217 register int i; 218 int aflags, error, allerror; 219 struct inode tip; 220 221 vnode_pager_setsize(ITOV(oip), length); 222 if (oip->i_size <= length) { 223 oip->i_flag |= ICHG|IUPD; 224 error = ffs_iupdat(oip, &time, &time, 1); 225 return (error); 226 } 227 /* 228 * Calculate index into inode's block list of 229 * last direct and indirect blocks (if any) 230 * which we want to keep. Lastblock is -1 when 231 * the file is truncated to 0. 232 */ 233 fs = oip->i_fs; 234 lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1; 235 lastiblock[SINGLE] = lastblock - NDADDR; 236 lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs); 237 lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs); 238 nblocks = btodb(fs->fs_bsize); 239 /* 240 * Update the size of the file. If the file is not being 241 * truncated to a block boundry, the contents of the 242 * partial block following the end of the file must be 243 * zero'ed in case it ever become accessable again because 244 * of subsequent file growth. 245 */ 246 osize = oip->i_size; 247 offset = blkoff(fs, length); 248 if (offset == 0) { 249 oip->i_size = length; 250 } else { 251 lbn = lblkno(fs, length); 252 aflags = B_CLRBUF; 253 if (flags & IO_SYNC) 254 aflags |= B_SYNC; 255 #ifdef QUOTA 256 if (error = getinoquota(oip)) 257 return (error); 258 #endif 259 if (error = ffs_balloc(oip, lbn, offset, &bp, aflags)) 260 return (error); 261 oip->i_size = length; 262 size = blksize(fs, oip, lbn); 263 (void) vnode_pager_uncache(ITOV(oip)); 264 bzero(bp->b_un.b_addr + offset, (unsigned)(size - offset)); 265 allocbuf(bp, size); 266 if (flags & IO_SYNC) 267 bwrite(bp); 268 else 269 bdwrite(bp); 270 } 271 /* 272 * Update file and block pointers on disk before we start freeing 273 * blocks. If we crash before free'ing blocks below, the blocks 274 * will be returned to the free list. lastiblock values are also 275 * normalized to -1 for calls to ffs_indirtrunc below. 276 */ 277 tip = *oip; 278 tip.i_size = osize; 279 for (level = TRIPLE; level >= SINGLE; level--) 280 if (lastiblock[level] < 0) { 281 oip->i_ib[level] = 0; 282 lastiblock[level] = -1; 283 } 284 for (i = NDADDR - 1; i > lastblock; i--) 285 oip->i_db[i] = 0; 286 oip->i_flag |= ICHG|IUPD; 287 vinvalbuf(ITOV(oip), (length > 0)); 288 allerror = ffs_iupdat(oip, &time, &time, MNT_WAIT); 289 290 /* 291 * Indirect blocks first. 292 */ 293 ip = &tip; 294 for (level = TRIPLE; level >= SINGLE; level--) { 295 bn = ip->i_ib[level]; 296 if (bn != 0) { 297 error = ffs_indirtrunc(ip, 298 bn, lastiblock[level], level, &count); 299 if (error) 300 allerror = error; 301 blocksreleased += count; 302 if (lastiblock[level] < 0) { 303 ip->i_ib[level] = 0; 304 ffs_blkfree(ip, bn, (off_t)fs->fs_bsize); 305 blocksreleased += nblocks; 306 } 307 } 308 if (lastiblock[level] >= 0) 309 goto done; 310 } 311 312 /* 313 * All whole direct blocks or frags. 314 */ 315 for (i = NDADDR - 1; i > lastblock; i--) { 316 register off_t bsize; 317 318 bn = ip->i_db[i]; 319 if (bn == 0) 320 continue; 321 ip->i_db[i] = 0; 322 bsize = (off_t)blksize(fs, ip, i); 323 ffs_blkfree(ip, bn, bsize); 324 blocksreleased += btodb(bsize); 325 } 326 if (lastblock < 0) 327 goto done; 328 329 /* 330 * Finally, look for a change in size of the 331 * last direct block; release any frags. 332 */ 333 bn = ip->i_db[lastblock]; 334 if (bn != 0) { 335 off_t oldspace, newspace; 336 337 /* 338 * Calculate amount of space we're giving 339 * back as old block size minus new block size. 340 */ 341 oldspace = blksize(fs, ip, lastblock); 342 ip->i_size = length; 343 newspace = blksize(fs, ip, lastblock); 344 if (newspace == 0) 345 panic("itrunc: newspace"); 346 if (oldspace - newspace > 0) { 347 /* 348 * Block number of space to be free'd is 349 * the old block # plus the number of frags 350 * required for the storage we're keeping. 351 */ 352 bn += numfrags(fs, newspace); 353 ffs_blkfree(ip, bn, oldspace - newspace); 354 blocksreleased += btodb(oldspace - newspace); 355 } 356 } 357 done: 358 /* BEGIN PARANOIA */ 359 for (level = SINGLE; level <= TRIPLE; level++) 360 if (ip->i_ib[level] != oip->i_ib[level]) 361 panic("itrunc1"); 362 for (i = 0; i < NDADDR; i++) 363 if (ip->i_db[i] != oip->i_db[i]) 364 panic("itrunc2"); 365 /* END PARANOIA */ 366 oip->i_blocks -= blocksreleased; 367 if (oip->i_blocks < 0) /* sanity */ 368 oip->i_blocks = 0; 369 oip->i_flag |= ICHG; 370 #ifdef QUOTA 371 if (!getinoquota(oip)) 372 (void) chkdq(oip, -blocksreleased, NOCRED, 0); 373 #endif 374 return (allerror); 375 } 376 377 /* 378 * Release blocks associated with the inode ip and stored in the indirect 379 * block bn. Blocks are free'd in LIFO order up to (but not including) 380 * lastbn. If level is greater than SINGLE, the block is an indirect block 381 * and recursive calls to indirtrunc must be used to cleanse other indirect 382 * blocks. 383 * 384 * NB: triple indirect blocks are untested. 385 */ 386 static int 387 ffs_indirtrunc(ip, bn, lastbn, level, countp) 388 register struct inode *ip; 389 daddr_t bn, lastbn; 390 int level; 391 long *countp; 392 { 393 register int i; 394 struct buf *bp; 395 register struct fs *fs = ip->i_fs; 396 register daddr_t *bap; 397 daddr_t *copy, nb, last; 398 long blkcount, factor; 399 int nblocks, blocksreleased = 0; 400 int error, allerror = 0; 401 402 /* 403 * Calculate index in current block of last 404 * block to be kept. -1 indicates the entire 405 * block so we need not calculate the index. 406 */ 407 factor = 1; 408 for (i = SINGLE; i < level; i++) 409 factor *= NINDIR(fs); 410 last = lastbn; 411 if (lastbn > 0) 412 last /= factor; 413 nblocks = btodb(fs->fs_bsize); 414 /* 415 * Get buffer of block pointers, zero those 416 * entries corresponding to blocks to be free'd, 417 * and update on disk copy first. 418 */ 419 error = bread(ip->i_devvp, fsbtodb(fs, bn), (int)fs->fs_bsize, 420 NOCRED, &bp); 421 if (error) { 422 brelse(bp); 423 *countp = 0; 424 return (error); 425 } 426 bap = bp->b_un.b_daddr; 427 MALLOC(copy, daddr_t *, fs->fs_bsize, M_TEMP, M_WAITOK); 428 bcopy((caddr_t)bap, (caddr_t)copy, (u_int)fs->fs_bsize); 429 bzero((caddr_t)&bap[last + 1], 430 (u_int)(NINDIR(fs) - (last + 1)) * sizeof (daddr_t)); 431 if (last == -1) 432 bp->b_flags |= B_INVAL; 433 error = bwrite(bp); 434 if (error) 435 allerror = error; 436 bap = copy; 437 438 /* 439 * Recursively free totally unused blocks. 440 */ 441 for (i = NINDIR(fs) - 1; i > last; i--) { 442 nb = bap[i]; 443 if (nb == 0) 444 continue; 445 if (level > SINGLE) { 446 if (error = ffs_indirtrunc(ip, 447 nb, (daddr_t)-1, level - 1, &blkcount)) 448 allerror = error; 449 blocksreleased += blkcount; 450 } 451 ffs_blkfree(ip, nb, (off_t)fs->fs_bsize); 452 blocksreleased += nblocks; 453 } 454 455 /* 456 * Recursively free last partial block. 457 */ 458 if (level > SINGLE && lastbn >= 0) { 459 last = lastbn % factor; 460 nb = bap[i]; 461 if (nb != 0) { 462 if (error = 463 ffs_indirtrunc(ip, nb, last, level - 1, &blkcount)) 464 allerror = error; 465 blocksreleased += blkcount; 466 } 467 } 468 FREE(copy, M_TEMP); 469 *countp = blocksreleased; 470 return (allerror); 471 } 472