Ignore machine-check MSRs

[freebsd-src/fkvm-freebsd.git] / sbin / dump / traverse.c

/*-
 * Copyright (c) 1980, 1988, 1991, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#ifndef lint
#if 0
static char sccsid[] = "@(#)traverse.c  8.7 (Berkeley) 6/15/95";
#endif
static const char rcsid[] =
  "$FreeBSD$";
#endif /* not lint */

#include <sys/param.h>
#include <sys/stat.h>

#include <ufs/ufs/dir.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#include <protocols/dumprestore.h>

#include <ctype.h>
#include <errno.h>
#include <inttypes.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <timeconv.h>
#include <unistd.h>

#include "dump.h"

union dinode {
        struct ufs1_dinode dp1;
        struct ufs2_dinode dp2;
};
#define DIP(dp, field) \
        ((sblock->fs_magic == FS_UFS1_MAGIC) ? \
        (dp)->dp1.field : (dp)->dp2.field)
#define DIP_SET(dp, field, val) do {\
        if (sblock->fs_magic == FS_UFS1_MAGIC) \
                (dp)->dp1.field = (val); \
        else \
                (dp)->dp2.field = (val); \
        } while (0)

#define HASDUMPEDFILE   0x1
#define HASSUBDIRS      0x2

static  int dirindir(ino_t ino, ufs2_daddr_t blkno, int level, long *size,
    long *tapesize, int nodump, ino_t maxino);
static  void dmpindir(union dinode *dp, ino_t ino, ufs2_daddr_t blk, int level,
    off_t *size);
static  void ufs1_blksout(ufs1_daddr_t *blkp, int frags, ino_t ino);
static  void ufs2_blksout(union dinode *dp, ufs2_daddr_t *blkp, int frags,
    ino_t ino, int last);
static  int appendextdata(union dinode *dp);
static  void writeextdata(union dinode *dp, ino_t ino, int added);
static  int searchdir(ino_t ino, ufs2_daddr_t blkno, long size, long filesize,
    long *tapesize, int nodump, ino_t maxino);
static  long blockest(union dinode *dp);

/*
 * This is an estimation of the number of TP_BSIZE blocks in the file.
 * It estimates the number of blocks in files with holes by assuming
 * that all of the blocks accounted for by di_blocks are data blocks
 * (when some of the blocks are usually used for indirect pointers);
 * hence the estimate may be high.
 */
static long
blockest(union dinode *dp)
{
        long blkest, sizeest;

        /*
         * dp->di_size is the size of the file in bytes.
         * dp->di_blocks stores the number of sectors actually in the file.
         * If there are more sectors than the size would indicate, this just
         *      means that there are indirect blocks in the file or unused
         *      sectors in the last file block; we can safely ignore these
         *      (blkest = sizeest below).
         * If the file is bigger than the number of sectors would indicate,
         *      then the file has holes in it.  In this case we must use the
         *      block count to estimate the number of data blocks used, but
         *      we use the actual size for estimating the number of indirect
         *      dump blocks (sizeest vs. blkest in the indirect block
         *      calculation).
         */
        if ((DIP(dp, di_flags) & SF_SNAPSHOT) != 0)
                return (1);
        blkest = howmany(dbtob(DIP(dp, di_blocks)), TP_BSIZE);
        sizeest = howmany(DIP(dp, di_size), TP_BSIZE);
        if (blkest > sizeest)
                blkest = sizeest;
        if (DIP(dp, di_size) > sblock->fs_bsize * NDADDR) {
                /* calculate the number of indirect blocks on the dump tape */
                blkest +=
                        howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
                        TP_NINDIR);
        }
        return (blkest + 1);
}

/* Auxiliary macro to pick up files changed since previous dump. */
#define CHANGEDSINCE(dp, t) \
        (DIP(dp, di_mtime) >= (t) || DIP(dp, di_ctime) >= (t))

/* The WANTTODUMP macro decides whether a file should be dumped. */
#ifdef UF_NODUMP
#define WANTTODUMP(dp) \
        (CHANGEDSINCE(dp, spcl.c_ddate) && \
         (nonodump || (DIP(dp, di_flags) & UF_NODUMP) != UF_NODUMP))
#else
#define WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
#endif

/*
 * Dump pass 1.
 *
 * Walk the inode list for a file system to find all allocated inodes
 * that have been modified since the previous dump time. Also, find all
 * the directories in the file system.
 */
int
mapfiles(ino_t maxino, long *tapesize)
{
        int i, cg, mode, inosused;
        int anydirskipped = 0;
        union dinode *dp;
        struct cg *cgp;
        ino_t ino;
        u_char *cp;

        if ((cgp = malloc(sblock->fs_cgsize)) == NULL)
                quit("mapfiles: cannot allocate memory.\n");
        for (cg = 0; cg < sblock->fs_ncg; cg++) {
                ino = cg * sblock->fs_ipg;
                bread(fsbtodb(sblock, cgtod(sblock, cg)), (char *)cgp,
                    sblock->fs_cgsize);
                if (sblock->fs_magic == FS_UFS2_MAGIC)
                        inosused = cgp->cg_initediblk;
                else
                        inosused = sblock->fs_ipg;
                /*
                 * If we are using soft updates, then we can trust the
                 * cylinder group inode allocation maps to tell us which
                 * inodes are allocated. We will scan the used inode map
                 * to find the inodes that are really in use, and then
                 * read only those inodes in from disk.
                 */
                if (sblock->fs_flags & FS_DOSOFTDEP) {
                        if (!cg_chkmagic(cgp))
                                quit("mapfiles: cg %d: bad magic number\n", cg);
                        cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
                        for ( ; inosused > 0; inosused -= CHAR_BIT, cp--) {
                                if (*cp == 0)
                                        continue;
                                for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
                                        if (*cp & i)
                                                break;
                                        inosused--;
                                }
                                break;
                        }
                        if (inosused <= 0)
                                continue;
                }
                for (i = 0; i < inosused; i++, ino++) {
                        if (ino < ROOTINO ||
                            (dp = getino(ino, &mode)) == NULL ||
                            (mode & IFMT) == 0)
                                continue;
                        if (ino >= maxino) {
                                msg("Skipping inode %d >= maxino %d\n",
                                    ino, maxino);
                                continue;
                        }
                        /*
                         * Everything must go in usedinomap so that a check
                         * for "in dumpdirmap but not in usedinomap" to detect
                         * dirs with nodump set has a chance of succeeding
                         * (this is used in mapdirs()).
                         */
                        SETINO(ino, usedinomap);
                        if (mode == IFDIR)
                                SETINO(ino, dumpdirmap);
                        if (WANTTODUMP(dp)) {
                                SETINO(ino, dumpinomap);
                                if (mode != IFREG &&
                                    mode != IFDIR &&
                                    mode != IFLNK)
                                        *tapesize += 1;
                                else
                                        *tapesize += blockest(dp);
                                continue;
                        }
                        if (mode == IFDIR) {
                                if (!nonodump &&
                                    (DIP(dp, di_flags) & UF_NODUMP))
                                        CLRINO(ino, usedinomap);
                                anydirskipped = 1;
                        }
                }
        }
        /*
         * Restore gets very upset if the root is not dumped,
         * so ensure that it always is dumped.
         */
        SETINO(ROOTINO, dumpinomap);
        return (anydirskipped);
}

/*
 * Dump pass 2.
 *
 * Scan each directory on the file system to see if it has any modified
 * files in it. If it does, and has not already been added to the dump
 * list (because it was itself modified), then add it. If a directory
 * has not been modified itself, contains no modified files and has no
 * subdirectories, then it can be deleted from the dump list and from
 * the list of directories. By deleting it from the list of directories,
 * its parent may now qualify for the same treatment on this or a later
 * pass using this algorithm.
 */
int
mapdirs(ino_t maxino, long *tapesize)
{
        union dinode *dp;
        int i, isdir, nodump;
        char *map;
        ino_t ino;
        union dinode di;
        long filesize;
        int ret, change = 0;

        isdir = 0;              /* XXX just to get gcc to shut up */
        for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
                if (((ino - 1) % CHAR_BIT) == 0)        /* map is offset by 1 */
                        isdir = *map++;
                else
                        isdir >>= 1;
                /*
                 * If a directory has been removed from usedinomap, it
                 * either has the nodump flag set, or has inherited
                 * it.  Although a directory can't be in dumpinomap if
                 * it isn't in usedinomap, we have to go through it to
                 * propagate the nodump flag.
                 */
                nodump = !nonodump && (TSTINO(ino, usedinomap) == 0);
                if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump))
                        continue;
                dp = getino(ino, &i);
                /*
                 * inode buf may change in searchdir().
                 */
                if (sblock->fs_magic == FS_UFS1_MAGIC)
                        di.dp1 = dp->dp1;
                else
                        di.dp2 = dp->dp2;
                filesize = DIP(&di, di_size);
                for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
                        if (DIP(&di, di_db[i]) != 0)
                                ret |= searchdir(ino, DIP(&di, di_db[i]),
                                    (long)sblksize(sblock, DIP(&di, di_size),
                                    i), filesize, tapesize, nodump, maxino);
                        if (ret & HASDUMPEDFILE)
                                filesize = 0;
                        else
                                filesize -= sblock->fs_bsize;
                }
                for (i = 0; filesize > 0 && i < NIADDR; i++) {
                        if (DIP(&di, di_ib[i]) == 0)
                                continue;
                        ret |= dirindir(ino, DIP(&di, di_ib[i]), i, &filesize,
                            tapesize, nodump, maxino);
                }
                if (ret & HASDUMPEDFILE) {
                        SETINO(ino, dumpinomap);
                        *tapesize += blockest(&di);
                        change = 1;
                        continue;
                }
                if (nodump) {
                        if (ret & HASSUBDIRS)
                                change = 1;     /* subdirs inherit nodump */
                        CLRINO(ino, dumpdirmap);
                } else if ((ret & HASSUBDIRS) == 0)
                        if (!TSTINO(ino, dumpinomap)) {
                                CLRINO(ino, dumpdirmap);
                                change = 1;
                        }
        }
        return (change);
}

/*
 * Read indirect blocks, and pass the data blocks to be searched
 * as directories. Quit as soon as any entry is found that will
 * require the directory to be dumped.
 */
static int
dirindir(
        ino_t ino,
        ufs2_daddr_t blkno,
        int ind_level,
        long *filesize,
        long *tapesize,
        int nodump,
        ino_t maxino)
{
        union {
                ufs1_daddr_t ufs1[MAXBSIZE / sizeof(ufs1_daddr_t)];
                ufs2_daddr_t ufs2[MAXBSIZE / sizeof(ufs2_daddr_t)];
        } idblk;
        int ret = 0;
        int i;

        bread(fsbtodb(sblock, blkno), (char *)&idblk, (int)sblock->fs_bsize);
        if (ind_level <= 0) {
                for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
                        if (sblock->fs_magic == FS_UFS1_MAGIC)
                                blkno = idblk.ufs1[i];
                        else
                                blkno = idblk.ufs2[i];
                        if (blkno != 0)
                                ret |= searchdir(ino, blkno, sblock->fs_bsize,
                                        *filesize, tapesize, nodump, maxino);
                        if (ret & HASDUMPEDFILE)
                                *filesize = 0;
                        else
                                *filesize -= sblock->fs_bsize;
                }
                return (ret);
        }
        ind_level--;
        for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
                if (sblock->fs_magic == FS_UFS1_MAGIC)
                        blkno = idblk.ufs1[i];
                else
                        blkno = idblk.ufs2[i];
                if (blkno != 0)
                        ret |= dirindir(ino, blkno, ind_level, filesize,
                            tapesize, nodump, maxino);
        }
        return (ret);
}

/*
 * Scan a disk block containing directory information looking to see if
 * any of the entries are on the dump list and to see if the directory
 * contains any subdirectories.
 */
static int
searchdir(
        ino_t ino,
        ufs2_daddr_t blkno,
        long size,
        long filesize, 
        long *tapesize,
        int nodump,
        ino_t maxino)
{
        int mode;
        struct direct *dp;
        union dinode *ip;
        long loc, ret = 0;
        static caddr_t dblk;

        if (dblk == NULL && (dblk = malloc(sblock->fs_bsize)) == NULL)
                quit("searchdir: cannot allocate indirect memory.\n");
        bread(fsbtodb(sblock, blkno), dblk, (int)size);
        if (filesize < size)
                size = filesize;
        for (loc = 0; loc < size; ) {
                dp = (struct direct *)(dblk + loc);
                if (dp->d_reclen == 0) {
                        msg("corrupted directory, inumber %d\n", ino);
                        break;
                }
                loc += dp->d_reclen;
                if (dp->d_ino == 0)
                        continue;
                if (dp->d_ino >= maxino) {
                        msg("corrupted directory entry, d_ino %d >= %d\n",
                            dp->d_ino, maxino);
                        break;
                }
                if (dp->d_name[0] == '.') {
                        if (dp->d_name[1] == '\0')
                                continue;
                        if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
                                continue;
                }
                if (nodump) {
                        ip = getino(dp->d_ino, &mode);
                        if (TSTINO(dp->d_ino, dumpinomap)) {
                                CLRINO(dp->d_ino, dumpinomap);
                                *tapesize -= blockest(ip);
                        }
                        /*
                         * Add back to dumpdirmap and remove from usedinomap
                         * to propagate nodump.
                         */
                        if (mode == IFDIR) {
                                SETINO(dp->d_ino, dumpdirmap);
                                CLRINO(dp->d_ino, usedinomap);
                                ret |= HASSUBDIRS;
                        }
                } else {
                        if (TSTINO(dp->d_ino, dumpinomap)) {
                                ret |= HASDUMPEDFILE;
                                if (ret & HASSUBDIRS)
                                        break;
                        }
                        if (TSTINO(dp->d_ino, dumpdirmap)) {
                                ret |= HASSUBDIRS;
                                if (ret & HASDUMPEDFILE)
                                        break;
                        }
                }
        }
        return (ret);
}

/*
 * Dump passes 3 and 4.
 *
 * Dump the contents of an inode to tape.
 */
void
dumpino(union dinode *dp, ino_t ino)
{
        int ind_level, cnt, last, added;
        off_t size;
        char buf[TP_BSIZE];

        if (newtape) {
                newtape = 0;
                dumpmap(dumpinomap, TS_BITS, ino);
        }
        CLRINO(ino, dumpinomap);
        /*
         * Zero out the size of a snapshot so that it will be dumped
         * as a zero length file.
         */
        if ((DIP(dp, di_flags) & SF_SNAPSHOT) != 0) {
                DIP_SET(dp, di_size, 0);
                DIP_SET(dp, di_flags, DIP(dp, di_flags) & ~SF_SNAPSHOT);
        }
        if (sblock->fs_magic == FS_UFS1_MAGIC) {
                spcl.c_mode = dp->dp1.di_mode;
                spcl.c_size = dp->dp1.di_size;
                spcl.c_extsize = 0;
                spcl.c_atime = _time32_to_time(dp->dp1.di_atime);
                spcl.c_atimensec = dp->dp1.di_atimensec;
                spcl.c_mtime = _time32_to_time(dp->dp1.di_mtime);
                spcl.c_mtimensec = dp->dp1.di_mtimensec;
                spcl.c_birthtime = 0;
                spcl.c_birthtimensec = 0;
                spcl.c_rdev = dp->dp1.di_rdev;
                spcl.c_file_flags = dp->dp1.di_flags;
                spcl.c_uid = dp->dp1.di_uid;
                spcl.c_gid = dp->dp1.di_gid;
        } else {
                spcl.c_mode = dp->dp2.di_mode;
                spcl.c_size = dp->dp2.di_size;
                spcl.c_extsize = dp->dp2.di_extsize;
                spcl.c_atime = _time64_to_time(dp->dp2.di_atime);
                spcl.c_atimensec = dp->dp2.di_atimensec;
                spcl.c_mtime = _time64_to_time(dp->dp2.di_mtime);
                spcl.c_mtimensec = dp->dp2.di_mtimensec;
                spcl.c_birthtime = _time64_to_time(dp->dp2.di_birthtime);
                spcl.c_birthtimensec = dp->dp2.di_birthnsec;
                spcl.c_rdev = dp->dp2.di_rdev;
                spcl.c_file_flags = dp->dp2.di_flags;
                spcl.c_uid = dp->dp2.di_uid;
                spcl.c_gid = dp->dp2.di_gid;
        }
        spcl.c_type = TS_INODE;
        spcl.c_count = 0;
        switch (DIP(dp, di_mode) & S_IFMT) {

        case 0:
                /*
                 * Freed inode.
                 */
                return;

        case S_IFLNK:
                /*
                 * Check for short symbolic link.
                 */
                if (DIP(dp, di_size) > 0 &&
                    DIP(dp, di_size) < sblock->fs_maxsymlinklen) {
                        spcl.c_addr[0] = 1;
                        spcl.c_count = 1;
                        added = appendextdata(dp);
                        writeheader(ino);
                        if (sblock->fs_magic == FS_UFS1_MAGIC)
                                memmove(buf, (caddr_t)dp->dp1.di_db,
                                    (u_long)DIP(dp, di_size));
                        else
                                memmove(buf, (caddr_t)dp->dp2.di_db,
                                    (u_long)DIP(dp, di_size));
                        buf[DIP(dp, di_size)] = '\0';
                        writerec(buf, 0);
                        writeextdata(dp, ino, added);
                        return;
                }
                /* FALLTHROUGH */

        case S_IFDIR:
        case S_IFREG:
                if (DIP(dp, di_size) > 0)
                        break;
                /* FALLTHROUGH */

        case S_IFIFO:
        case S_IFSOCK:
        case S_IFCHR:
        case S_IFBLK:
                added = appendextdata(dp);
                writeheader(ino);
                writeextdata(dp, ino, added);
                return;

        default:
                msg("Warning: undefined file type 0%o\n",
                    DIP(dp, di_mode) & IFMT);
                return;
        }
        if (DIP(dp, di_size) > NDADDR * sblock->fs_bsize) {
                cnt = NDADDR * sblock->fs_frag;
                last = 0;
        } else {
                cnt = howmany(DIP(dp, di_size), sblock->fs_fsize);
                last = 1;
        }
        if (sblock->fs_magic == FS_UFS1_MAGIC)
                ufs1_blksout(&dp->dp1.di_db[0], cnt, ino);
        else
                ufs2_blksout(dp, &dp->dp2.di_db[0], cnt, ino, last);
        if ((size = DIP(dp, di_size) - NDADDR * sblock->fs_bsize) <= 0)
                return;
        for (ind_level = 0; ind_level < NIADDR; ind_level++) {
                dmpindir(dp, ino, DIP(dp, di_ib[ind_level]), ind_level, &size);
                if (size <= 0)
                        return;
        }
}

/*
 * Read indirect blocks, and pass the data blocks to be dumped.
 */
static void
dmpindir(union dinode *dp, ino_t ino, ufs2_daddr_t blk, int ind_level,
        off_t *size)
{
        union {
                ufs1_daddr_t ufs1[MAXBSIZE / sizeof(ufs1_daddr_t)];
                ufs2_daddr_t ufs2[MAXBSIZE / sizeof(ufs2_daddr_t)];
        } idblk;
        int i, cnt, last;

        if (blk != 0)
                bread(fsbtodb(sblock, blk), (char *)&idblk,
                    (int)sblock->fs_bsize);
        else
                memset(&idblk, 0, sblock->fs_bsize);
        if (ind_level <= 0) {
                if (*size > NINDIR(sblock) * sblock->fs_bsize) {
                        cnt = NINDIR(sblock) * sblock->fs_frag;
                        last = 0;
                } else {
                        cnt = howmany(*size, sblock->fs_fsize);
                        last = 1;
                }
                *size -= NINDIR(sblock) * sblock->fs_bsize;
                if (sblock->fs_magic == FS_UFS1_MAGIC)
                        ufs1_blksout(idblk.ufs1, cnt, ino);
                else
                        ufs2_blksout(dp, idblk.ufs2, cnt, ino, last);
                return;
        }
        ind_level--;
        for (i = 0; i < NINDIR(sblock); i++) {
                if (sblock->fs_magic == FS_UFS1_MAGIC)
                        dmpindir(dp, ino, idblk.ufs1[i], ind_level, size);
                else
                        dmpindir(dp, ino, idblk.ufs2[i], ind_level, size);
                if (*size <= 0)
                        return;
        }
}

/*
 * Collect up the data into tape record sized buffers and output them.
 */
static void
ufs1_blksout(ufs1_daddr_t *blkp, int frags, ino_t ino)
{
        ufs1_daddr_t *bp;
        int i, j, count, blks, tbperdb;

        blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
        tbperdb = sblock->fs_bsize >> tp_bshift;
        for (i = 0; i < blks; i += TP_NINDIR) {
                if (i + TP_NINDIR > blks)
                        count = blks;
                else
                        count = i + TP_NINDIR;
                for (j = i; j < count; j++)
                        if (blkp[j / tbperdb] != 0)
                                spcl.c_addr[j - i] = 1;
                        else
                                spcl.c_addr[j - i] = 0;
                spcl.c_count = count - i;
                writeheader(ino);
                bp = &blkp[i / tbperdb];
                for (j = i; j < count; j += tbperdb, bp++)
                        if (*bp != 0) {
                                if (j + tbperdb <= count)
                                        dumpblock(*bp, (int)sblock->fs_bsize);
                                else
                                        dumpblock(*bp, (count - j) * TP_BSIZE);
                        }
                spcl.c_type = TS_ADDR;
        }
}

/*
 * Collect up the data into tape record sized buffers and output them.
 */
static void
ufs2_blksout(union dinode *dp, ufs2_daddr_t *blkp, int frags, ino_t ino,
        int last)
{
        ufs2_daddr_t *bp;
        int i, j, count, resid, blks, tbperdb, added;
        static int writingextdata = 0;

        /*
         * Calculate the number of TP_BSIZE blocks to be dumped.
         * For filesystems with a fragment size bigger than TP_BSIZE,
         * only part of the final fragment may need to be dumped.
         */
        blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
        if (last) {
                resid = howmany(fragoff(sblock, dp->dp2.di_size), TP_BSIZE);
                if (resid > 0)
                        blks -= howmany(sblock->fs_fsize, TP_BSIZE) - resid;
        }
        tbperdb = sblock->fs_bsize >> tp_bshift;
        for (i = 0; i < blks; i += TP_NINDIR) {
                if (i + TP_NINDIR > blks)
                        count = blks;
                else
                        count = i + TP_NINDIR;
                for (j = i; j < count; j++)
                        if (blkp[j / tbperdb] != 0)
                                spcl.c_addr[j - i] = 1;
                        else
                                spcl.c_addr[j - i] = 0;
                spcl.c_count = count - i;
                if (last && count == blks && !writingextdata)
                        added = appendextdata(dp);
                writeheader(ino);
                bp = &blkp[i / tbperdb];
                for (j = i; j < count; j += tbperdb, bp++)
                        if (*bp != 0) {
                                if (j + tbperdb <= count)
                                        dumpblock(*bp, (int)sblock->fs_bsize);
                                else
                                        dumpblock(*bp, (count - j) * TP_BSIZE);
                        }
                spcl.c_type = TS_ADDR;
                spcl.c_count = 0;
                if (last && count == blks && !writingextdata) {
                        writingextdata = 1;
                        writeextdata(dp, ino, added);
                        writingextdata = 0;
                }
        }
}

/*
 * If there is room in the current block for the extended attributes
 * as well as the file data, update the header to reflect the added
 * attribute data at the end. Attributes are placed at the end so that
 * old versions of restore will correctly restore the file and simply
 * discard the extra data at the end that it does not understand.
 * The attribute data is dumped following the file data by the
 * writeextdata() function (below).
 */
static int
appendextdata(union dinode *dp)
{
        int i, blks, tbperdb;

        /*
         * If no extended attributes, there is nothing to do.
         */
        if (spcl.c_extsize == 0)
                return (0);
        /*
         * If there is not enough room at the end of this block
         * to add the extended attributes, then rather than putting
         * part of them here, we simply push them entirely into a
         * new block rather than putting some here and some later.
         */
        if (spcl.c_extsize > NXADDR * sblock->fs_bsize)
                blks = howmany(NXADDR * sblock->fs_bsize, TP_BSIZE);
        else
                blks = howmany(spcl.c_extsize, TP_BSIZE);
        if (spcl.c_count + blks > TP_NINDIR)
                return (0);
        /*
         * Update the block map in the header to indicate the added
         * extended attribute. They will be appended after the file
         * data by the writeextdata() routine.
         */
        tbperdb = sblock->fs_bsize >> tp_bshift;
        for (i = 0; i < blks; i++)
                if (&dp->dp2.di_extb[i / tbperdb] != 0)
                                spcl.c_addr[spcl.c_count + i] = 1;
                        else
                                spcl.c_addr[spcl.c_count + i] = 0;
        spcl.c_count += blks;
        return (blks);
}

/*
 * Dump the extended attribute data. If there was room in the file
 * header, then all we need to do is output the data blocks. If there
 * was not room in the file header, then an additional TS_ADDR header
 * is created to hold the attribute data.
 */
static void
writeextdata(union dinode *dp, ino_t ino, int added)
{
        int i, frags, blks, tbperdb, last;
        ufs2_daddr_t *bp;
        off_t size;

        /*
         * If no extended attributes, there is nothing to do.
         */
        if (spcl.c_extsize == 0)
                return;
        /*
         * If there was no room in the file block for the attributes,
         * dump them out in a new block, otherwise just dump the data.
         */
        if (added == 0) {
                if (spcl.c_extsize > NXADDR * sblock->fs_bsize) {
                        frags = NXADDR * sblock->fs_frag;
                        last = 0;
                } else {
                        frags = howmany(spcl.c_extsize, sblock->fs_fsize);
                        last = 1;
                }
                ufs2_blksout(dp, &dp->dp2.di_extb[0], frags, ino, last);
        } else {
                if (spcl.c_extsize > NXADDR * sblock->fs_bsize)
                        blks = howmany(NXADDR * sblock->fs_bsize, TP_BSIZE);
                else
                        blks = howmany(spcl.c_extsize, TP_BSIZE);
                tbperdb = sblock->fs_bsize >> tp_bshift;
                for (i = 0; i < blks; i += tbperdb) {
                        bp = &dp->dp2.di_extb[i / tbperdb];
                        if (*bp != 0) {
                                if (i + tbperdb <= blks)
                                        dumpblock(*bp, (int)sblock->fs_bsize);
                                else
                                        dumpblock(*bp, (blks - i) * TP_BSIZE);
                        }
                }

        }
        /*
         * If an indirect block is added for extended attributes, then
         * di_exti below should be changed to the structure element
         * that references the extended attribute indirect block. This
         * definition is here only to make it compile without complaint.
         */
#define di_exti di_spare[0]
        /*
         * If the extended attributes fall into an indirect block,
         * dump it as well.
         */
        if ((size = spcl.c_extsize - NXADDR * sblock->fs_bsize) > 0)
                dmpindir(dp, ino, dp->dp2.di_exti, 0, &size);
}

/*
 * Dump a map to the tape.
 */
void
dumpmap(char *map, int type, ino_t ino)
{
        int i;
        char *cp;

        spcl.c_type = type;
        spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
        writeheader(ino);
        for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
                writerec(cp, 0);
}

/*
 * Write a header record to the dump tape.
 */
void
writeheader(ino_t ino)
{
        int32_t sum, cnt, *lp;

        if (rsync_friendly >= 2) {
                /* don't track changes to access time */
                spcl.c_atime = spcl.c_mtime;
                spcl.c_atimensec = spcl.c_mtimensec;
        }
        spcl.c_inumber = ino;
        spcl.c_magic = FS_UFS2_MAGIC;
        spcl.c_checksum = 0;
        lp = (int32_t *)&spcl;
        sum = 0;
        cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
        while (--cnt >= 0) {
                sum += *lp++;
                sum += *lp++;
                sum += *lp++;
                sum += *lp++;
        }
        spcl.c_checksum = CHECKSUM - sum;
        writerec((char *)&spcl, 1);
}

union dinode *
getino(ino_t inum, int *modep)
{
        static ino_t minino, maxino;
        static caddr_t inoblock;
        struct ufs1_dinode *dp1;
        struct ufs2_dinode *dp2;

        if (inoblock == NULL && (inoblock = malloc(sblock->fs_bsize)) == NULL)
                quit("cannot allocate inode memory.\n");
        curino = inum;
        if (inum >= minino && inum < maxino)
                goto gotit;
        bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), inoblock,
            (int)sblock->fs_bsize);
        minino = inum - (inum % INOPB(sblock));
        maxino = minino + INOPB(sblock);
gotit:
        if (sblock->fs_magic == FS_UFS1_MAGIC) {
                dp1 = &((struct ufs1_dinode *)inoblock)[inum - minino];
                *modep = (dp1->di_mode & IFMT);
                return ((union dinode *)dp1);
        }
        dp2 = &((struct ufs2_dinode *)inoblock)[inum - minino];
        *modep = (dp2->di_mode & IFMT);
        return ((union dinode *)dp2);
}

/*
 * Read a chunk of data from the disk.
 * Try to recover from hard errors by reading in sector sized pieces.
 * Error recovery is attempted at most BREADEMAX times before seeking
 * consent from the operator to continue.
 */
int     breaderrors = 0;
#define BREADEMAX 32

void
bread(ufs2_daddr_t blkno, char *buf, int size)
{
        int secsize, bytes, resid, xfer, base, cnt, i;
        static char *tmpbuf;
        off_t offset;

loop:
        offset = blkno << dev_bshift;
        secsize = sblock->fs_fsize;
        base = offset % secsize;
        resid = size % secsize;
        /*
         * If the transfer request starts or ends on a non-sector
         * boundary, we must read the entire sector and copy out
         * just the part that we need.
         */
        if (base == 0 && resid == 0) {
                cnt = cread(diskfd, buf, size, offset);
                if (cnt == size)
                        return;
        } else {
                if (tmpbuf == NULL && (tmpbuf = malloc(secsize)) == 0)
                        quit("buffer malloc failed\n");
                xfer = 0;
                bytes = size;
                if (base != 0) {
                        cnt = cread(diskfd, tmpbuf, secsize, offset - base);
                        if (cnt != secsize)
                                goto bad;
                        xfer = MIN(secsize - base, size);
                        offset += xfer;
                        bytes -= xfer;
                        resid = bytes % secsize;
                        memcpy(buf, &tmpbuf[base], xfer);
                }
                if (bytes >= secsize) {
                        cnt = cread(diskfd, &buf[xfer], bytes - resid, offset);
                        if (cnt != bytes - resid)
                                goto bad;
                        xfer += cnt;
                        offset += cnt;
                }
                if (resid == 0)
                        return;
                cnt = cread(diskfd, tmpbuf, secsize, offset);
                if (cnt == secsize) {
                        memcpy(&buf[xfer], tmpbuf, resid);
                        return;
                }
        }
bad:
        if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
                /*
                 * Trying to read the final fragment.
                 *
                 * NB - dump only works in TP_BSIZE blocks, hence
                 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
                 * It should be smarter about not actually trying to
                 * read more than it can get, but for the time being
                 * we punt and scale back the read only when it gets
                 * us into trouble. (mkm 9/25/83)
                 */
                size -= dev_bsize;
                goto loop;
        }
        if (cnt == -1)
                msg("read error from %s: %s: [block %jd]: count=%d\n",
                        disk, strerror(errno), (intmax_t)blkno, size);
        else
                msg("short read error from %s: [block %jd]: count=%d, got=%d\n",
                        disk, (intmax_t)blkno, size, cnt);
        if (++breaderrors > BREADEMAX) {
                msg("More than %d block read errors from %s\n",
                        BREADEMAX, disk);
                broadcast("DUMP IS AILING!\n");
                msg("This is an unrecoverable error.\n");
                if (!query("Do you want to attempt to continue?")){
                        dumpabort(0);
                        /*NOTREACHED*/
                } else
                        breaderrors = 0;
        }
        /*
         * Zero buffer, then try to read each sector of buffer separately,
         * and bypass the cache.
         */
        memset(buf, 0, size);
        for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
                if ((cnt = pread(diskfd, buf, (int)dev_bsize,
                    ((off_t)blkno << dev_bshift))) == dev_bsize)
                        continue;
                if (cnt == -1) {
                        msg("read error from %s: %s: [sector %jd]: count=%ld\n",
                            disk, strerror(errno), (intmax_t)blkno, dev_bsize);
                        continue;
                }
                msg("short read from %s: [sector %jd]: count=%ld, got=%d\n",
                    disk, (intmax_t)blkno, dev_bsize, cnt);
        }
}