sbin/dump/traverse.c

   1 /*-
   2  * Copyright (c) 1980, 1988, 1991, 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. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#)traverse.c       8.7 (Berkeley) 6/15/95
  30  * $FreeBSD: src/sbin/dump/traverse.c,v 1.10.2.6 2003/04/14 20:10:35 johan Exp $
  31  */
  32
  33 #include <sys/param.h>
  34 #include <sys/stat.h>
  35 #include <vfs/ufs/dir.h>
  36 #include <vfs/ufs/dinode.h>
  37 #include <vfs/ufs/fs.h>
  38
  39 #include <protocols/dumprestore.h>
  40
  41 #include <ctype.h>
  42 #include <stdio.h>
  43 #include <errno.h>
  44 #include <string.h>
  45 #include <unistd.h>
  46
  47 #include "dump.h"
  48
  49 #define HASDUMPEDFILE   0x1
  50 #define HASSUBDIRS      0x2
  51
  52 #ifdef  FS_44INODEFMT
  53 typedef quad_t fsizeT;
  54 #else
  55 typedef long fsizeT;
  56 #endif
  57
  58 static int      dirindir(ufs1_ino_t, daddr_t, int, long *, long *, int);
  59 static void     dmpindir(ufs1_ino_t, daddr_t, int, fsizeT *);
  60 static  int searchdir(ufs1_ino_t, daddr_t, long, long, long *, int);
  61
  62 /*
  63  * This is an estimation of the number of TP_BSIZE blocks in the file.
  64  * It estimates the number of blocks in files with holes by assuming
  65  * that all of the blocks accounted for by di_blocks are data blocks
  66  * (when some of the blocks are usually used for indirect pointers);
  67  * hence the estimate may be high.
  68  */
  69 long
  70 blockest(struct ufs1_dinode *dp)
  71 {
  72         long blkest, sizeest;
  73
  74         /*
  75          * dp->di_size is the size of the file in bytes.
  76          * dp->di_blocks stores the number of sectors actually in the file.
  77          * If there are more sectors than the size would indicate, this just
  78          *      means that there are indirect blocks in the file or unused
  79          *      sectors in the last file block; we can safely ignore these
  80          *      (blkest = sizeest below).
  81          * If the file is bigger than the number of sectors would indicate,
  82          *      then the file has holes in it.  In this case we must use the
  83          *      block count to estimate the number of data blocks used, but
  84          *      we use the actual size for estimating the number of indirect
  85          *      dump blocks (sizeest vs. blkest in the indirect block
  86          *      calculation).
  87          */
  88         blkest = howmany(dbtob(dp->di_blocks), TP_BSIZE);
  89         sizeest = howmany(dp->di_size, TP_BSIZE);
  90         if (blkest > sizeest)
  91                 blkest = sizeest;
  92         if (dp->di_size > (unsigned)sblock->fs_bsize * UFS_NDADDR) {
  93                 /* calculate the number of indirect blocks on the dump tape */
  94                 blkest +=
  95                         howmany(sizeest - UFS_NDADDR * sblock->fs_bsize / TP_BSIZE,
  96                         TP_NINDIR);
  97         }
  98         return (blkest + 1);
  99 }
 100
 101 /* Auxiliary macro to pick up files changed since previous dump. */
 102 #define CHANGEDSINCE(dp, t) \
 103         ((dp)->di_mtime >= (t) || (dp)->di_ctime >= (t))
 104
 105 /* The WANTTODUMP macro decides whether a file should be dumped. */
 106 #ifdef UF_NODUMP
 107 #define WANTTODUMP(dp) \
 108         (CHANGEDSINCE(dp, spcl.c_ddate) && \
 109          (nonodump || ((dp)->di_flags & UF_NODUMP) != UF_NODUMP))
 110 #else
 111 #define WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
 112 #endif
 113
 114 /*
 115  * Dump pass 1.
 116  *
 117  * Walk the inode list for a filesystem to find all allocated inodes
 118  * that have been modified since the previous dump time. Also, find all
 119  * the directories in the filesystem.
 120  */
 121 int
 122 mapfiles(ufs1_ino_t maxino, long *tape_size)
 123 {
 124         int mode;
 125         ufs1_ino_t ino;
 126         struct ufs1_dinode *dp;
 127         int anydirskipped = 0;
 128
 129         for (ino = UFS_ROOTINO; ino < maxino; ino++) {
 130                 dp = getino(ino);
 131                 if ((mode = (dp->di_mode & IFMT)) == 0)
 132                         continue;
 133                 /*
 134                  * Everything must go in usedinomap so that a check
 135                  * for "in dumpdirmap but not in usedinomap" to detect
 136                  * dirs with nodump set has a chance of succeeding
 137                  * (this is used in mapdirs()).
 138                  */
 139                 SETINO(ino, usedinomap);
 140                 if (mode == IFDIR)
 141                         SETINO(ino, dumpdirmap);
 142                 if (WANTTODUMP(dp)) {
 143                         SETINO(ino, dumpinomap);
 144                         if (mode != IFREG && mode != IFDIR && mode != IFLNK)
 145                                 *tape_size += 1;
 146                         else
 147                                 *tape_size += blockest(dp);
 148                         continue;
 149                 }
 150                 if (mode == IFDIR) {
 151                         if (!nonodump && (dp->di_flags & UF_NODUMP))
 152                                 CLRINO(ino, usedinomap);
 153                         anydirskipped = 1;
 154                 }
 155         }
 156         /*
 157          * Restore gets very upset if the root is not dumped,
 158          * so ensure that it always is dumped.
 159          */
 160         SETINO(UFS_ROOTINO, dumpinomap);
 161         return (anydirskipped);
 162 }
 163
 164 /*
 165  * Dump pass 2.
 166  *
 167  * Scan each directory on the filesystem to see if it has any modified
 168  * files in it. If it does, and has not already been added to the dump
 169  * list (because it was itself modified), then add it. If a directory
 170  * has not been modified itself, contains no modified files and has no
 171  * subdirectories, then it can be deleted from the dump list and from
 172  * the list of directories. By deleting it from the list of directories,
 173  * its parent may now qualify for the same treatment on this or a later
 174  * pass using this algorithm.
 175  */
 176 int
 177 mapdirs(ufs1_ino_t maxino, long *tape_size)
 178 {
 179         struct  ufs1_dinode *dp;
 180         int isdir, nodump;
 181         unsigned int i;
 182         char *map;
 183         ufs1_ino_t ino;
 184         struct ufs1_dinode di;
 185         long filesize;
 186         int ret, change = 0;
 187
 188         isdir = 0;              /* XXX just to get gcc to shut up */
 189         for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
 190                 if (((ino - 1) % NBBY) == 0)    /* map is offset by 1 */
 191                         isdir = *map++;
 192                 else
 193                         isdir >>= 1;
 194                 /*
 195                  * If a directory has been removed from usedinomap, it
 196                  * either has the nodump flag set, or has inherited
 197                  * it.  Although a directory can't be in dumpinomap if
 198                  * it isn't in usedinomap, we have to go through it to
 199                  * propagate the nodump flag.
 200                  */
 201                 nodump = !nonodump && (TSTINO(ino, usedinomap) == 0);
 202                 if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump))
 203                         continue;
 204                 dp = getino(ino);
 205                 di = *dp;       /* inode buf may change in searchdir(). */
 206                 filesize = di.di_size;
 207                 for (ret = 0, i = 0; filesize > 0 && i < UFS_NDADDR; i++) {
 208                         if (di.di_db[i] != 0) {
 209                                 ret |= searchdir(ino, di.di_db[i],
 210                                         (long)dblksize(sblock, &di, i),
 211                                         filesize, tape_size, nodump);
 212                         }
 213                         if (ret & HASDUMPEDFILE)
 214                                 filesize = 0;
 215                         else
 216                                 filesize -= sblock->fs_bsize;
 217                 }
 218                 for (i = 0; filesize > 0 && i < UFS_NIADDR; i++) {
 219                         if (di.di_ib[i] == 0)
 220                                 continue;
 221                         ret |= dirindir(ino, di.di_ib[i], i, &filesize,
 222                             tape_size, nodump);
 223                 }
 224                 if (ret & HASDUMPEDFILE) {
 225                         SETINO(ino, dumpinomap);
 226                         *tape_size += blockest(&di);
 227                         change = 1;
 228                         continue;
 229                 }
 230                 if (nodump) {
 231                         if (ret & HASSUBDIRS)
 232                                 change = 1;     /* subdirs inherit nodump */
 233                         CLRINO(ino, dumpdirmap);
 234                 } else if ((ret & HASSUBDIRS) == 0)
 235                         if (!TSTINO(ino, dumpinomap)) {
 236                                 CLRINO(ino, dumpdirmap);
 237                                 change = 1;
 238                         }
 239         }
 240         return (change);
 241 }
 242
 243 /*
 244  * Read indirect blocks, and pass the data blocks to be searched
 245  * as directories. Quit as soon as any entry is found that will
 246  * require the directory to be dumped.
 247  */
 248 static int
 249 dirindir(ufs1_ino_t ino, daddr_t blkno, int ind_level, long *filesize,
 250          long *tape_size, int nodump)
 251 {
 252         int ret = 0;
 253         int i;
 254         daddr_t idblk[MAXNINDIR];
 255
 256         bread(fsbtodb(sblock, blkno), (char *)idblk, (int)sblock->fs_bsize);
 257         if (ind_level <= 0) {
 258                 for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
 259                         blkno = idblk[i];
 260                         if (blkno != 0) {
 261                                 ret |= searchdir(ino, blkno, sblock->fs_bsize,
 262                                         *filesize, tape_size, nodump);
 263                         }
 264                         if (ret & HASDUMPEDFILE)
 265                                 *filesize = 0;
 266                         else
 267                                 *filesize -= sblock->fs_bsize;
 268                 }
 269                 return (ret);
 270         }
 271         ind_level--;
 272         for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
 273                 blkno = idblk[i];
 274                 if (blkno != 0) {
 275                         ret |= dirindir(ino, blkno, ind_level, filesize,
 276                             tape_size, nodump);
 277                 }
 278         }
 279         return (ret);
 280 }
 281
 282 /*
 283  * Scan a disk block containing directory information looking to see if
 284  * any of the entries are on the dump list and to see if the directory
 285  * contains any subdirectories.
 286  */
 287 static int
 288 searchdir(ufs1_ino_t ino, daddr_t blkno, long size, long filesize,
 289           long *tape_size, int nodump)
 290 {
 291         struct direct *dp;
 292         struct ufs1_dinode *ip;
 293         long loc, ret = 0;
 294         char dblk[MAXBSIZE];
 295
 296         bread(fsbtodb(sblock, blkno), dblk, (int)size);
 297         if (filesize < size)
 298                 size = filesize;
 299         for (loc = 0; loc < size; ) {
 300                 dp = (struct direct *)(dblk + loc);
 301                 if (dp->d_reclen == 0) {
 302                         msg("corrupted directory, inumber %d\n", ino);
 303                         break;
 304                 }
 305                 loc += dp->d_reclen;
 306                 if (dp->d_ino == 0)
 307                         continue;
 308                 if (dp->d_name[0] == '.') {
 309                         if (dp->d_name[1] == '\0')
 310                                 continue;
 311                         if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
 312                                 continue;
 313                 }
 314                 if (nodump) {
 315                         ip = getino(dp->d_ino);
 316                         if (TSTINO(dp->d_ino, dumpinomap)) {
 317                                 CLRINO(dp->d_ino, dumpinomap);
 318                                 *tape_size -= blockest(ip);
 319                         }
 320                         /*
 321                          * Add back to dumpdirmap and remove from usedinomap
 322                          * to propagate nodump.
 323                          */
 324                         if ((ip->di_mode & IFMT) == IFDIR) {
 325                                 SETINO(dp->d_ino, dumpdirmap);
 326                                 CLRINO(dp->d_ino, usedinomap);
 327                                 ret |= HASSUBDIRS;
 328                         }
 329                 } else {
 330                         if (TSTINO(dp->d_ino, dumpinomap)) {
 331                                 ret |= HASDUMPEDFILE;
 332                                 if (ret & HASSUBDIRS)
 333                                         break;
 334                         }
 335                         if (TSTINO(dp->d_ino, dumpdirmap)) {
 336                                 ret |= HASSUBDIRS;
 337                                 if (ret & HASDUMPEDFILE)
 338                                         break;
 339                         }
 340                 }
 341         }
 342         return (ret);
 343 }
 344
 345 /*
 346  * Dump passes 3 and 4.
 347  *
 348  * Dump the contents of an inode to tape.
 349  */
 350 void
 351 dumpino(struct ufs1_dinode *dp, ufs1_ino_t ino)
 352 {
 353         int ind_level, cnt;
 354         fsizeT size;
 355         char buf[TP_BSIZE];
 356
 357         if (newtape) {
 358                 newtape = 0;
 359                 dumpmap(dumpinomap, TS_BITS, ino);
 360         }
 361         CLRINO(ino, dumpinomap);
 362         spcl.c_dinode = *dp;
 363         spcl.c_type = TS_INODE;
 364         spcl.c_count = 0;
 365         switch (dp->di_mode & S_IFMT) {
 366
 367         case 0:
 368                 /*
 369                  * Freed inode.
 370                  */
 371                 return;
 372
 373         case S_IFLNK:
 374                 /*
 375                  * Check for short symbolic link.
 376                  */
 377 #ifdef FS_44INODEFMT
 378                 if (dp->di_size > 0 &&
 379                     dp->di_size < (unsigned)sblock->fs_maxsymlinklen) {
 380                         spcl.c_addr[0] = 1;
 381                         spcl.c_count = 1;
 382                         writeheader(ino);
 383                         memmove(buf, dp->di_shortlink, (u_long)dp->di_size);
 384                         buf[dp->di_size] = '\0';
 385                         writerec(buf, 0);
 386                         return;
 387                 }
 388 #endif
 389                 /* fall through */
 390
 391         case S_IFDIR:
 392         case S_IFREG:
 393                 if (dp->di_size > 0)
 394                         break;
 395                 /* fall through */
 396
 397         case S_IFIFO:
 398         case S_IFSOCK:
 399         case S_IFCHR:
 400         case S_IFBLK:
 401                 writeheader(ino);
 402                 return;
 403
 404         default:
 405                 msg("Warning: undefined file type 0%o\n", dp->di_mode & IFMT);
 406                 return;
 407         }
 408         if (dp->di_size > UFS_NDADDR * (unsigned)sblock->fs_bsize)
 409                 cnt = UFS_NDADDR * sblock->fs_frag;
 410         else
 411                 cnt = howmany(dp->di_size, sblock->fs_fsize);
 412         blksout(&dp->di_db[0], cnt, ino);
 413         if ((size = dp->di_size - UFS_NDADDR * sblock->fs_bsize) <= 0)
 414                 return;
 415         for (ind_level = 0; ind_level < UFS_NIADDR; ind_level++) {
 416                 dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
 417                 if (size <= 0)
 418                         return;
 419         }
 420 }
 421
 422 /*
 423  * Read indirect blocks, and pass the data blocks to be dumped.
 424  */
 425 static void
 426 dmpindir(ufs1_ino_t ino, daddr_t blk, int ind_level, fsizeT *size)
 427 {
 428         int i, cnt;
 429         daddr_t idblk[MAXNINDIR];
 430
 431         if (blk != 0)
 432                 bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
 433         else
 434                 memset(idblk, 0, (int)sblock->fs_bsize);
 435         if (ind_level <= 0) {
 436                 if (*size < NINDIR(sblock) * sblock->fs_bsize)
 437                         cnt = howmany(*size, sblock->fs_fsize);
 438                 else
 439                         cnt = NINDIR(sblock) * sblock->fs_frag;
 440                 *size -= NINDIR(sblock) * sblock->fs_bsize;
 441                 blksout(&idblk[0], cnt, ino);
 442                 return;
 443         }
 444         ind_level--;
 445         for (i = 0; i < NINDIR(sblock); i++) {
 446                 dmpindir(ino, idblk[i], ind_level, size);
 447                 if (*size <= 0)
 448                         return;
 449         }
 450 }
 451
 452 /*
 453  * Collect up the data into tape record sized buffers and output them.
 454  */
 455 void
 456 blksout(daddr_t *blkp, int frags, ufs1_ino_t ino)
 457 {
 458         daddr_t *bp;
 459         int i, j, count, blks, tbperdb;
 460
 461         blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
 462         tbperdb = sblock->fs_bsize >> tp_bshift;
 463         for (i = 0; i < blks; i += TP_NINDIR) {
 464                 if (i + TP_NINDIR > blks)
 465                         count = blks;
 466                 else
 467                         count = i + TP_NINDIR;
 468                 for (j = i; j < count; j++)
 469                         if (blkp[j / tbperdb] != 0)
 470                                 spcl.c_addr[j - i] = 1;
 471                         else
 472                                 spcl.c_addr[j - i] = 0;
 473                 spcl.c_count = count - i;
 474                 writeheader(ino);
 475                 bp = &blkp[i / tbperdb];
 476                 for (j = i; j < count; j += tbperdb, bp++)
 477                         if (*bp != 0) {
 478                                 if (j + tbperdb <= count)
 479                                         dumpblock(*bp, (int)sblock->fs_bsize);
 480                                 else
 481                                         dumpblock(*bp, (count - j) * TP_BSIZE);
 482                         }
 483                 spcl.c_type = TS_ADDR;
 484         }
 485 }
 486
 487 /*
 488  * Dump a map to the tape.
 489  */
 490 void
 491 dumpmap(const char *map, int type, ufs1_ino_t ino)
 492 {
 493         int i;
 494         const char *cp;
 495
 496         spcl.c_type = type;
 497         spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
 498         writeheader(ino);
 499         for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
 500                 writerec(cp, 0);
 501 }
 502
 503 /*
 504  * Write a header record to the dump tape.
 505  */
 506 void
 507 writeheader(ufs1_ino_t ino)
 508 {
 509         int32_t sum, cnt, *lp;
 510
 511         spcl.c_inumber = ino;
 512         spcl.c_magic = NFS_MAGIC;
 513         spcl.c_checksum = 0;
 514         lp = (int32_t *)&spcl;
 515         sum = 0;
 516         cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
 517         while (--cnt >= 0) {
 518                 sum += *lp++;
 519                 sum += *lp++;
 520                 sum += *lp++;
 521                 sum += *lp++;
 522         }
 523         spcl.c_checksum = CHECKSUM - sum;
 524         writerec(&spcl, 1);
 525 }
 526
 527 struct ufs1_dinode *
 528 getino(ufs1_ino_t inum)
 529 {
 530         static daddr_t minino, maxino;
 531         static struct ufs1_dinode inoblock[MAXINOPB];
 532
 533         curino = inum;
 534         if (inum >= (unsigned)minino && inum < (unsigned)maxino)
 535                 return (&inoblock[inum - minino]);
 536         bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), (char *)inoblock,
 537             (int)sblock->fs_bsize);
 538         minino = inum - (inum % INOPB(sblock));
 539         maxino = minino + INOPB(sblock);
 540         return (&inoblock[inum - minino]);
 541 }
 542
 543 /*
 544  * Read a chunk of data from the disk.
 545  * Try to recover from hard errors by reading in sector sized pieces.
 546  * Error recovery is attempted at most BREADEMAX times before seeking
 547  * consent from the operator to continue.
 548  */
 549 int     breaderrors = 0;
 550 #define BREADEMAX 32
 551
 552 void
 553 bread(daddr_t blkno, char *buf, int size)
 554 {
 555         int cnt, i;
 556
 557 loop:
 558         cnt = cread(diskfd, buf, size, ((off_t)blkno << dev_bshift));
 559         if (cnt == size)
 560                 return;
 561         if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
 562                 /*
 563                  * Trying to read the final fragment.
 564                  *
 565                  * NB - dump only works in TP_BSIZE blocks, hence
 566                  * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
 567                  * It should be smarter about not actually trying to
 568                  * read more than it can get, but for the time being
 569                  * we punt and scale back the read only when it gets
 570                  * us into trouble. (mkm 9/25/83)
 571                  */
 572                 size -= dev_bsize;
 573                 goto loop;
 574         }
 575         if (cnt == -1)
 576                 msg("read error from %s: %s: [block %d]: count=%d\n",
 577                         disk, strerror(errno), blkno, size);
 578         else
 579                 msg("short read error from %s: [block %d]: count=%d, got=%d\n",
 580                         disk, blkno, size, cnt);
 581         if (++breaderrors > BREADEMAX) {
 582                 msg("More than %d block read errors from %s\n",
 583                         BREADEMAX, disk);
 584                 broadcast("DUMP IS AILING!\n");
 585                 msg("This is an unrecoverable error.\n");
 586                 if (!query("Do you want to attempt to continue?")){
 587                         dumpabort(0);
 588                         /*NOTREACHED*/
 589                 } else
 590                         breaderrors = 0;
 591         }
 592         /*
 593          * Zero buffer, then try to read each sector of buffer separately,
 594          * and bypass the cache.
 595          */
 596         memset(buf, 0, size);
 597         for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
 598                 if ((cnt = pread(diskfd, buf, (int)dev_bsize,
 599                     ((off_t)blkno << dev_bshift))) == dev_bsize)
 600                         continue;
 601                 if (cnt == -1) {
 602                         msg("read error from %s: %s: [sector %d]: count=%ld\n",
 603                                 disk, strerror(errno), blkno, dev_bsize);
 604                         continue;
 605                 }
 606                 msg("short read error from %s: [sector %d]: count=%ld, got=%d\n",
 607                         disk, blkno, dev_bsize, cnt);
 608         }
 609 }