After r232548, clang complains about the apparent '=-' operator (a

[FreeBSD/FreeBSD.git] / sbin / growfs / growfs.c

/*
 * Copyright (c) 2000 Christoph Herrmann, Thomas-Henning von Kamptz
 * Copyright (c) 1980, 1989, 1993 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Christoph Herrmann and Thomas-Henning von Kamptz, Munich and Frankfurt.
 *
 * 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgment:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors, as well as Christoph
 *      Herrmann and Thomas-Henning von Kamptz.
 * 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.
 *
 * $TSHeader: src/sbin/growfs/growfs.c,v 1.5 2000/12/12 19:31:00 tomsoft Exp $
 *
 */

#ifndef lint
static const char copyright[] =
"@(#) Copyright (c) 2000 Christoph Herrmann, Thomas-Henning von Kamptz\n\
Copyright (c) 1980, 1989, 1993 The Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

#include <sys/param.h>
#include <sys/disklabel.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/disk.h>

#include <stdio.h>
#include <paths.h>
#include <ctype.h>
#include <err.h>
#include <fcntl.h>
#include <limits.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <ufs/ufs/dinode.h>
#include <ufs/ffs/fs.h>

#include "debug.h"

#ifdef FS_DEBUG
int     _dbg_lvl_ = (DL_INFO);  /* DL_TRC */
#endif /* FS_DEBUG */

static union {
        struct fs       fs;
        char    pad[SBLOCKSIZE];
} fsun1, fsun2;
#define sblock  fsun1.fs        /* the new superblock */
#define osblock fsun2.fs        /* the old superblock */

/*
 * Possible superblock locations ordered from most to least likely.
 */
static int sblock_try[] = SBLOCKSEARCH;
static ufs2_daddr_t sblockloc;

static union {
        struct cg       cg;
        char    pad[MAXBSIZE];
} cgun1, cgun2;
#define acg     cgun1.cg        /* a cylinder cgroup (new) */
#define aocg    cgun2.cg        /* an old cylinder group */

static char     ablk[MAXBSIZE]; /* a block */

static struct csum      *fscs;  /* cylinder summary */

union dinode {
        struct ufs1_dinode dp1;
        struct ufs2_dinode dp2;
};
#define DIP(dp, field) \
        ((sblock.fs_magic == FS_UFS1_MAGIC) ? \
        (uint32_t)(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)
static ufs2_daddr_t     inoblk;                 /* inode block address */
static char             inobuf[MAXBSIZE];       /* inode block */
static ino_t            maxino;                 /* last valid inode */
static int              unlabeled; /* unlabeled partition, e.g. vinum volume */

/*
 * An array of elements of type struct gfs_bpp describes all blocks to
 * be relocated in order to free the space needed for the cylinder group
 * summary for all cylinder groups located in the first cylinder group.
 */
struct gfs_bpp {
        ufs2_daddr_t    old;            /* old block number */
        ufs2_daddr_t    new;            /* new block number */
#define GFS_FL_FIRST    1
#define GFS_FL_LAST     2
        unsigned int    flags;  /* special handling required */
        int             found;  /* how many references were updated */
};

static void     growfs(int, int, unsigned int);
static void     rdfs(ufs2_daddr_t, size_t, void *, int);
static void     wtfs(ufs2_daddr_t, size_t, void *, int, unsigned int);
static ufs2_daddr_t alloc(void);
static int      charsperline(void);
static void     usage(void);
static int      isblock(struct fs *, unsigned char *, int);
static void     clrblock(struct fs *, unsigned char *, int);
static void     setblock(struct fs *, unsigned char *, int);
static void     initcg(int, time_t, int, unsigned int);
static void     updjcg(int, time_t, int, int, unsigned int);
static void     updcsloc(time_t, int, int, unsigned int);
static struct disklabel *get_disklabel(int);
static void     return_disklabel(int, struct disklabel *, unsigned int);
static union dinode *ginode(ino_t, int, int);
static void     frag_adjust(ufs2_daddr_t, int);
static int      cond_bl_upd(ufs2_daddr_t *, struct gfs_bpp *, int, int,
                    unsigned int);
static void     updclst(int);
static void     updrefs(int, ino_t, struct gfs_bpp *, int, int, unsigned int);
static void     indirchk(ufs_lbn_t, ufs_lbn_t, ufs2_daddr_t, ufs_lbn_t,
                    struct gfs_bpp *, int, int, unsigned int);
static void     get_dev_size(int, int *);

/*
 * Here we actually start growing the file system. We basically read the
 * cylinder summary from the first cylinder group as we want to update
 * this on the fly during our various operations. First we handle the
 * changes in the former last cylinder group. Afterwards we create all new
 * cylinder groups.  Now we handle the cylinder group containing the
 * cylinder summary which might result in a relocation of the whole
 * structure.  In the end we write back the updated cylinder summary, the
 * new superblock, and slightly patched versions of the super block
 * copies.
 */
static void
growfs(int fsi, int fso, unsigned int Nflag)
{
        DBG_FUNC("growfs")
        time_t modtime;
        uint cylno;
        int i, j, width;
        char tmpbuf[100];
#ifdef FSIRAND
        static int randinit=0;

        DBG_ENTER;

        if (!randinit) {
                randinit = 1;
                srandomdev();
        }
#else /* not FSIRAND */

        DBG_ENTER;

#endif /* FSIRAND */
        time(&modtime);

        /*
         * Get the cylinder summary into the memory.
         */
        fscs = (struct csum *)calloc((size_t)1, (size_t)sblock.fs_cssize);
        if (fscs == NULL)
                errx(1, "calloc failed");
        for (i = 0; i < osblock.fs_cssize; i += osblock.fs_bsize) {
                rdfs(fsbtodb(&osblock, osblock.fs_csaddr +
                    numfrags(&osblock, i)), (size_t)MIN(osblock.fs_cssize - i,
                    osblock.fs_bsize), (void *)(((char *)fscs) + i), fsi);
        }

#ifdef FS_DEBUG
        {
                struct csum *dbg_csp;
                int dbg_csc;
                char dbg_line[80];

                dbg_csp = fscs;

                for (dbg_csc = 0; dbg_csc < osblock.fs_ncg; dbg_csc++) {
                        snprintf(dbg_line, sizeof(dbg_line),
                            "%d. old csum in old location", dbg_csc);
                        DBG_DUMP_CSUM(&osblock, dbg_line, dbg_csp++);
                }
        }
#endif /* FS_DEBUG */
        DBG_PRINT0("fscs read\n");

        /*
         * Do all needed changes in the former last cylinder group.
         */
        updjcg(osblock.fs_ncg - 1, modtime, fsi, fso, Nflag);

        /*
         * Dump out summary information about file system.
         */
#       define B2MBFACTOR (1 / (1024.0 * 1024.0))
        printf("growfs: %.1fMB (%jd sectors) block size %d, fragment size %d\n",
            (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
            (intmax_t)fsbtodb(&sblock, sblock.fs_size), sblock.fs_bsize,
            sblock.fs_fsize);
        printf("\tusing %d cylinder groups of %.2fMB, %d blks, %d inodes.\n",
            sblock.fs_ncg, (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
            sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
        if (sblock.fs_flags & FS_DOSOFTDEP)
                printf("\twith soft updates\n");
#       undef B2MBFACTOR

        /*
         * Now build the cylinders group blocks and
         * then print out indices of cylinder groups.
         */
        printf("super-block backups (for fsck -b #) at:\n");
        i = 0;
        width = charsperline();

        /*
         * Iterate for only the new cylinder groups.
         */
        for (cylno = osblock.fs_ncg; cylno < sblock.fs_ncg; cylno++) {
                initcg(cylno, modtime, fso, Nflag);
                j = sprintf(tmpbuf, " %jd%s",
                    (intmax_t)fsbtodb(&sblock, cgsblock(&sblock, cylno)),
                    cylno < (sblock.fs_ncg - 1) ? "," : "" );
                if (i + j >= width) {
                        printf("\n");
                        i = 0;
                }
                i += j;
                printf("%s", tmpbuf);
                fflush(stdout);
        }
        printf("\n");

        /*
         * Do all needed changes in the first cylinder group.
         * allocate blocks in new location
         */
        updcsloc(modtime, fsi, fso, Nflag);

        /*
         * Now write the cylinder summary back to disk.
         */
        for (i = 0; i < sblock.fs_cssize; i += sblock.fs_bsize) {
                wtfs(fsbtodb(&sblock, sblock.fs_csaddr + numfrags(&sblock, i)),
                    (size_t)MIN(sblock.fs_cssize - i, sblock.fs_bsize),
                    (void *)(((char *)fscs) + i), fso, Nflag);
        }
        DBG_PRINT0("fscs written\n");

#ifdef FS_DEBUG
        {
                struct csum     *dbg_csp;
                int     dbg_csc;
                char    dbg_line[80];

                dbg_csp = fscs;
                for (dbg_csc = 0; dbg_csc < sblock.fs_ncg; dbg_csc++) {
                        snprintf(dbg_line, sizeof(dbg_line),
                            "%d. new csum in new location", dbg_csc);
                        DBG_DUMP_CSUM(&sblock, dbg_line, dbg_csp++);
                }
        }
#endif /* FS_DEBUG */

        /*
         * Now write the new superblock back to disk.
         */
        sblock.fs_time = modtime;
        wtfs(sblockloc, (size_t)SBLOCKSIZE, (void *)&sblock, fso, Nflag);
        DBG_PRINT0("sblock written\n");
        DBG_DUMP_FS(&sblock, "new initial sblock");

        /*
         * Clean up the dynamic fields in our superblock copies.
         */
        sblock.fs_fmod = 0;
        sblock.fs_clean = 1;
        sblock.fs_ronly = 0;
        sblock.fs_cgrotor = 0;
        sblock.fs_state = 0;
        memset((void *)&sblock.fs_fsmnt, 0, sizeof(sblock.fs_fsmnt));
        sblock.fs_flags &= FS_DOSOFTDEP;

        /*
         * XXX
         * The following fields are currently distributed from the superblock
         * to the copies:
         *     fs_minfree
         *     fs_rotdelay
         *     fs_maxcontig
         *     fs_maxbpg
         *     fs_minfree,
         *     fs_optim
         *     fs_flags regarding SOFTPDATES
         *
         * We probably should rather change the summary for the cylinder group
         * statistics here to the value of what would be in there, if the file
         * system were created initially with the new size. Therefor we still
         * need to find an easy way of calculating that.
         * Possibly we can try to read the first superblock copy and apply the
         * "diffed" stats between the old and new superblock by still copying
         * certain parameters onto that.
         */

        /*
         * Write out the duplicate super blocks.
         */
        for (cylno = 0; cylno < sblock.fs_ncg; cylno++) {
                wtfs(fsbtodb(&sblock, cgsblock(&sblock, cylno)),
                    (size_t)SBLOCKSIZE, (void *)&sblock, fso, Nflag);
        }
        DBG_PRINT0("sblock copies written\n");
        DBG_DUMP_FS(&sblock, "new other sblocks");

        DBG_LEAVE;
        return;
}

/*
 * This creates a new cylinder group structure, for more details please see
 * the source of newfs(8), as this function is taken over almost unchanged.
 * As this is never called for the first cylinder group, the special
 * provisions for that case are removed here.
 */
static void
initcg(int cylno, time_t modtime, int fso, unsigned int Nflag)
{
        DBG_FUNC("initcg")
        static caddr_t iobuf;
        long blkno, start;
        ufs2_daddr_t i, cbase, dmax;
#ifdef FSIRAND
        struct ufs1_dinode *dp1;
#endif
        struct csum *cs;
        uint d, dupper, dlower;

        if (iobuf == NULL && (iobuf = malloc(sblock.fs_bsize * 3)) == NULL)
                errx(37, "panic: cannot allocate I/O buffer");

        /*
         * Determine block bounds for cylinder group.
         * Allow space for super block summary information in first
         * cylinder group.
         */
        cbase = cgbase(&sblock, cylno);
        dmax = cbase + sblock.fs_fpg;
        if (dmax > sblock.fs_size)
                dmax = sblock.fs_size;
        dlower = cgsblock(&sblock, cylno) - cbase;
        dupper = cgdmin(&sblock, cylno) - cbase;
        if (cylno == 0) /* XXX fscs may be relocated */
                dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
        cs = &fscs[cylno];
        memset(&acg, 0, sblock.fs_cgsize);
        acg.cg_time = modtime;
        acg.cg_magic = CG_MAGIC;
        acg.cg_cgx = cylno;
        acg.cg_niblk = sblock.fs_ipg;
        acg.cg_initediblk = sblock.fs_ipg < 2 * INOPB(&sblock) ?
            sblock.fs_ipg : 2 * INOPB(&sblock);
        acg.cg_ndblk = dmax - cbase;
        if (sblock.fs_contigsumsize > 0)
                acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
        start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
        if (sblock.fs_magic == FS_UFS2_MAGIC) {
                acg.cg_iusedoff = start;
        } else {
                acg.cg_old_ncyl = sblock.fs_old_cpg;
                acg.cg_old_time = acg.cg_time;
                acg.cg_time = 0;
                acg.cg_old_niblk = acg.cg_niblk;
                acg.cg_niblk = 0;
                acg.cg_initediblk = 0;
                acg.cg_old_btotoff = start;
                acg.cg_old_boff = acg.cg_old_btotoff +
                    sblock.fs_old_cpg * sizeof(int32_t);
                acg.cg_iusedoff = acg.cg_old_boff +
                    sblock.fs_old_cpg * sizeof(u_int16_t);
        }
        acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
        acg.cg_nextfreeoff = acg.cg_freeoff + howmany(sblock.fs_fpg, CHAR_BIT);
        if (sblock.fs_contigsumsize > 0) {
                acg.cg_clustersumoff =
                    roundup(acg.cg_nextfreeoff, sizeof(u_int32_t));
                acg.cg_clustersumoff -= sizeof(u_int32_t);
                acg.cg_clusteroff = acg.cg_clustersumoff +
                    (sblock.fs_contigsumsize + 1) * sizeof(u_int32_t);
                acg.cg_nextfreeoff = acg.cg_clusteroff +
                    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
        }
        if (acg.cg_nextfreeoff > (unsigned)sblock.fs_cgsize) {
                /*
                 * This should never happen as we would have had that panic
                 * already on file system creation
                 */
                errx(37, "panic: cylinder group too big");
        }
        acg.cg_cs.cs_nifree += sblock.fs_ipg;
        if (cylno == 0)
                for (i = 0; i < ROOTINO; i++) {
                        setbit(cg_inosused(&acg), i);
                        acg.cg_cs.cs_nifree--;
                }
        /*
         * For the old file system, we have to initialize all the inodes.
         */
        if (sblock.fs_magic == FS_UFS1_MAGIC) {
                bzero(iobuf, sblock.fs_bsize);
                for (i = 0; i < sblock.fs_ipg / INOPF(&sblock);
                    i += sblock.fs_frag) {
#ifdef FSIRAND
                        dp1 = (struct ufs1_dinode *)(void *)iobuf;
                        for (j = 0; j < INOPB(&sblock); j++) {
                                dp1->di_gen = random();
                                dp1++;
                        }
#endif
                        wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
                            sblock.fs_bsize, iobuf, fso, Nflag);
                }
        }
        if (cylno > 0) {
                /*
                 * In cylno 0, beginning space is reserved
                 * for boot and super blocks.
                 */
                for (d = 0; d < dlower; d += sblock.fs_frag) {
                        blkno = d / sblock.fs_frag;
                        setblock(&sblock, cg_blksfree(&acg), blkno);
                        if (sblock.fs_contigsumsize > 0)
                                setbit(cg_clustersfree(&acg), blkno);
                        acg.cg_cs.cs_nbfree++;
                }
                sblock.fs_dsize += dlower;
        }
        sblock.fs_dsize += acg.cg_ndblk - dupper;
        if ((i = dupper % sblock.fs_frag)) {
                acg.cg_frsum[sblock.fs_frag - i]++;
                for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
                        setbit(cg_blksfree(&acg), dupper);
                        acg.cg_cs.cs_nffree++;
                }
        }
        for (d = dupper; d + sblock.fs_frag <= acg.cg_ndblk;
            d += sblock.fs_frag) {
                blkno = d / sblock.fs_frag;
                setblock(&sblock, cg_blksfree(&acg), blkno);
                if (sblock.fs_contigsumsize > 0)
                        setbit(cg_clustersfree(&acg), blkno);
                acg.cg_cs.cs_nbfree++;
        }
        if (d < acg.cg_ndblk) {
                acg.cg_frsum[acg.cg_ndblk - d]++;
                for (; d < acg.cg_ndblk; d++) {
                        setbit(cg_blksfree(&acg), d);
                        acg.cg_cs.cs_nffree++;
                }
        }
        if (sblock.fs_contigsumsize > 0) {
                int32_t *sump = cg_clustersum(&acg);
                u_char *mapp = cg_clustersfree(&acg);
                int map = *mapp++;
                int bit = 1;
                int run = 0;

                for (i = 0; i < acg.cg_nclusterblks; i++) {
                        if ((map & bit) != 0)
                                run++;
                        else if (run != 0) {
                                if (run > sblock.fs_contigsumsize)
                                        run = sblock.fs_contigsumsize;
                                sump[run]++;
                                run = 0;
                        }
                        if ((i & (CHAR_BIT - 1)) != CHAR_BIT - 1)
                                bit <<= 1;
                        else {
                                map = *mapp++;
                                bit = 1;
                        }
                }
                if (run != 0) {
                        if (run > sblock.fs_contigsumsize)
                                run = sblock.fs_contigsumsize;
                        sump[run]++;
                }
        }
        sblock.fs_cstotal.cs_ndir += acg.cg_cs.cs_ndir;
        sblock.fs_cstotal.cs_nffree += acg.cg_cs.cs_nffree;
        sblock.fs_cstotal.cs_nbfree += acg.cg_cs.cs_nbfree;
        sblock.fs_cstotal.cs_nifree += acg.cg_cs.cs_nifree;
        *cs = acg.cg_cs;

        memcpy(iobuf, &acg, sblock.fs_cgsize);
        memset(iobuf + sblock.fs_cgsize, '\0',
            sblock.fs_bsize * 3 - sblock.fs_cgsize);

        wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)),
            sblock.fs_bsize * 3, iobuf, fso, Nflag);
        DBG_DUMP_CG(&sblock, "new cg", &acg);

        DBG_LEAVE;
        return;
}

/*
 * Here we add or subtract (sign +1/-1) the available fragments in a given
 * block to or from the fragment statistics. By subtracting before and adding
 * after an operation on the free frag map we can easy update the fragment
 * statistic, which seems to be otherwise a rather complex operation.
 */
static void
frag_adjust(ufs2_daddr_t frag, int sign)
{
        DBG_FUNC("frag_adjust")
        int fragsize;
        int f;

        DBG_ENTER;

        fragsize=0;
        /*
         * Here frag only needs to point to any fragment in the block we want
         * to examine.
         */
        for (f = rounddown(frag, sblock.fs_frag);
            f < roundup(frag + 1, sblock.fs_frag); f++) {
                /*
                 * Count contiguous free fragments.
                 */
                if (isset(cg_blksfree(&acg), f)) {
                        fragsize++;
                } else {
                        if (fragsize && fragsize < sblock.fs_frag) {
                                /*
                                 * We found something in between.
                                 */
                                acg.cg_frsum[fragsize]+=sign;
                                DBG_PRINT2("frag_adjust [%d]+=%d\n",
                                    fragsize, sign);
                        }
                        fragsize = 0;
                }
        }
        if (fragsize && fragsize < sblock.fs_frag) {
                /*
                 * We found something.
                 */
                acg.cg_frsum[fragsize] += sign;
                DBG_PRINT2("frag_adjust [%d]+=%d\n", fragsize, sign);
        }
        DBG_PRINT2("frag_adjust [[%d]]+=%d\n", fragsize, sign);

        DBG_LEAVE;
        return;
}

/*
 * Here we conditionally update a pointer to a fragment. We check for all
 * relocated blocks if any of its fragments is referenced by the current
 * field, and update the pointer to the respective fragment in our new
 * block.  If we find a reference we write back the block immediately,
 * as there is no easy way for our general block reading engine to figure
 * out if a write back operation is needed.
 */
static int
cond_bl_upd(ufs2_daddr_t *block, struct gfs_bpp *field, int fsi, int fso,
    unsigned int Nflag)
{
        DBG_FUNC("cond_bl_upd")
        struct gfs_bpp *f;
        ufs2_daddr_t src, dst;
        int fragnum;
        void *ibuf;

        DBG_ENTER;

        for (f = field; f->old != 0; f++) {
                src = *block;
                if (fragstoblks(&sblock, src) != f->old)
                        continue;
                /*
                 * The fragment is part of the block, so update.
                 */
                dst = blkstofrags(&sblock, f->new);
                fragnum = fragnum(&sblock, src);
                *block = dst + fragnum;
                f->found++;
                DBG_PRINT3("scg (%jd->%jd)[%d] reference updated\n",
                    (intmax_t)f->old, (intmax_t)f->new, fragnum);

                /*
                 * Copy the block back immediately.
                 *
                 * XXX  If src is from an indirect block we have
                 *      to implement copy on write here in case of
                 *      active snapshots.
                 */
                ibuf = malloc(sblock.fs_bsize);
                if (!ibuf)
                        errx(1, "malloc failed");
                src -= fragnum;
                rdfs(fsbtodb(&sblock, src), (size_t)sblock.fs_bsize, ibuf, fsi);
                wtfs(dst, (size_t)sblock.fs_bsize, ibuf, fso, Nflag);
                free(ibuf);
                /*
                 * The same block can't be found again in this loop.
                 */
                return (1);
        }

        DBG_LEAVE;
        return (0);
}

/*
 * Here we do all needed work for the former last cylinder group. It has to be
 * changed in any case, even if the file system ended exactly on the end of
 * this group, as there is some slightly inconsistent handling of the number
 * of cylinders in the cylinder group. We start again by reading the cylinder
 * group from disk. If the last block was not fully available, we first handle
 * the missing fragments, then we handle all new full blocks in that file
 * system and finally we handle the new last fragmented block in the file
 * system.  We again have to handle the fragment statistics rotational layout
 * tables and cluster summary during all those operations.
 */
static void
updjcg(int cylno, time_t modtime, int fsi, int fso, unsigned int Nflag)
{
        DBG_FUNC("updjcg")
        ufs2_daddr_t cbase, dmax, dupper;
        struct csum *cs;
        int i, k;
        int j = 0;

        DBG_ENTER;

        /*
         * Read the former last (joining) cylinder group from disk, and make
         * a copy.
         */
        rdfs(fsbtodb(&osblock, cgtod(&osblock, cylno)),
            (size_t)osblock.fs_cgsize, (void *)&aocg, fsi);
        DBG_PRINT0("jcg read\n");
        DBG_DUMP_CG(&sblock, "old joining cg", &aocg);

        memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));

        /*
         * If the cylinder group had already its new final size almost
         * nothing is to be done ... except:
         * For some reason the value of cg_ncyl in the last cylinder group has
         * to be zero instead of fs_cpg. As this is now no longer the last
         * cylinder group we have to change that value now to fs_cpg.
         */

        if (cgbase(&osblock, cylno + 1) == osblock.fs_size) {
                if (sblock.fs_magic == FS_UFS1_MAGIC)
                        acg.cg_old_ncyl=sblock.fs_old_cpg;

                wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)),
                    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
                DBG_PRINT0("jcg written\n");
                DBG_DUMP_CG(&sblock, "new joining cg", &acg);

                DBG_LEAVE;
                return;
        }

        /*
         * Set up some variables needed later.
         */
        cbase = cgbase(&sblock, cylno);
        dmax = cbase + sblock.fs_fpg;
        if (dmax > sblock.fs_size)
                dmax = sblock.fs_size;
        dupper = cgdmin(&sblock, cylno) - cbase;
        if (cylno == 0) /* XXX fscs may be relocated */
                dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);

        /*
         * Set pointer to the cylinder summary for our cylinder group.
         */
        cs = fscs + cylno;

        /*
         * Touch the cylinder group, update all fields in the cylinder group as
         * needed, update the free space in the superblock.
         */
        acg.cg_time = modtime;
        if ((unsigned)cylno == sblock.fs_ncg - 1) {
                /*
                 * This is still the last cylinder group.
                 */
                if (sblock.fs_magic == FS_UFS1_MAGIC)
                        acg.cg_old_ncyl =
                            sblock.fs_old_ncyl % sblock.fs_old_cpg;
        } else {
                acg.cg_old_ncyl = sblock.fs_old_cpg;
        }
        DBG_PRINT2("jcg dbg: %d %u", cylno, sblock.fs_ncg);
#ifdef FS_DEBUG
        if (sblock.fs_magic == FS_UFS1_MAGIC)
                DBG_PRINT2("%d %u", acg.cg_old_ncyl, sblock.fs_old_cpg);
#endif
        DBG_PRINT0("\n");
        acg.cg_ndblk = dmax - cbase;
        sblock.fs_dsize += acg.cg_ndblk - aocg.cg_ndblk;
        if (sblock.fs_contigsumsize > 0)
                acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;

        /*
         * Now we have to update the free fragment bitmap for our new free
         * space.  There again we have to handle the fragmentation and also
         * the rotational layout tables and the cluster summary.  This is
         * also done per fragment for the first new block if the old file
         * system end was not on a block boundary, per fragment for the new
         * last block if the new file system end is not on a block boundary,
         * and per block for all space in between.
         *
         * Handle the first new block here if it was partially available
         * before.
         */
        if (osblock.fs_size % sblock.fs_frag) {
                if (roundup(osblock.fs_size, sblock.fs_frag) <=
                    sblock.fs_size) {
                        /*
                         * The new space is enough to fill at least this
                         * block
                         */
                        j = 0;
                        for (i = roundup(osblock.fs_size - cbase,
                            sblock.fs_frag) - 1; i >= osblock.fs_size - cbase;
                            i--) {
                                setbit(cg_blksfree(&acg), i);
                                acg.cg_cs.cs_nffree++;
                                j++;
                        }

                        /*
                         * Check if the fragment just created could join an
                         * already existing fragment at the former end of the
                         * file system.
                         */
                        if (isblock(&sblock, cg_blksfree(&acg),
                            ((osblock.fs_size - cgbase(&sblock, cylno)) /
                             sblock.fs_frag))) {
                                /*
                                 * The block is now completely available.
                                 */
                                DBG_PRINT0("block was\n");
                                acg.cg_frsum[osblock.fs_size % sblock.fs_frag]--;
                                acg.cg_cs.cs_nbfree++;
                                acg.cg_cs.cs_nffree -= sblock.fs_frag;
                                k = rounddown(osblock.fs_size - cbase,
                                    sblock.fs_frag);
                                updclst((osblock.fs_size - cbase) /
                                    sblock.fs_frag);
                        } else {
                                /*
                                 * Lets rejoin a possible partially growed
                                 * fragment.
                                 */
                                k = 0;
                                while (isset(cg_blksfree(&acg), i) &&
                                    (i >= rounddown(osblock.fs_size - cbase,
                                    sblock.fs_frag))) {
                                        i--;
                                        k++;
                                }
                                if (k)
                                        acg.cg_frsum[k]--;
                                acg.cg_frsum[k + j]++;
                        }
                } else {
                        /*
                         * We only grow by some fragments within this last
                         * block.
                         */
                        for (i = sblock.fs_size - cbase - 1;
                            i >= osblock.fs_size - cbase; i--) {
                                setbit(cg_blksfree(&acg), i);
                                acg.cg_cs.cs_nffree++;
                                j++;
                        }
                        /*
                         * Lets rejoin a possible partially growed fragment.
                         */
                        k = 0;
                        while (isset(cg_blksfree(&acg), i) &&
                            (i >= rounddown(osblock.fs_size - cbase,
                            sblock.fs_frag))) {
                                i--;
                                k++;
                        }
                        if (k)
                                acg.cg_frsum[k]--;
                        acg.cg_frsum[k + j]++;
                }
        }

        /*
         * Handle all new complete blocks here.
         */
        for (i = roundup(osblock.fs_size - cbase, sblock.fs_frag);
            i + sblock.fs_frag <= dmax - cbase; /* XXX <= or only < ? */
            i += sblock.fs_frag) {
                j = i / sblock.fs_frag;
                setblock(&sblock, cg_blksfree(&acg), j);
                updclst(j);
                acg.cg_cs.cs_nbfree++;
        }

        /*
         * Handle the last new block if there are stll some new fragments left.
         * Here we don't have to bother about the cluster summary or the even
         * the rotational layout table.
         */
        if (i < (dmax - cbase)) {
                acg.cg_frsum[dmax - cbase - i]++;
                for (; i < dmax - cbase; i++) {
                        setbit(cg_blksfree(&acg), i);
                        acg.cg_cs.cs_nffree++;
                }
        }

        sblock.fs_cstotal.cs_nffree +=
            (acg.cg_cs.cs_nffree - aocg.cg_cs.cs_nffree);
        sblock.fs_cstotal.cs_nbfree +=
            (acg.cg_cs.cs_nbfree - aocg.cg_cs.cs_nbfree);
        /*
         * The following statistics are not changed here:
         *     sblock.fs_cstotal.cs_ndir
         *     sblock.fs_cstotal.cs_nifree
         * As the statistics for this cylinder group are ready, copy it to
         * the summary information array.
         */
        *cs = acg.cg_cs;

        /*
         * Write the updated "joining" cylinder group back to disk.
         */
        wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)), (size_t)sblock.fs_cgsize,
            (void *)&acg, fso, Nflag);
        DBG_PRINT0("jcg written\n");
        DBG_DUMP_CG(&sblock, "new joining cg", &acg);

        DBG_LEAVE;
        return;
}

/*
 * Here we update the location of the cylinder summary. We have two possible
 * ways of growing the cylinder summary.
 * (1)  We can try to grow the summary in the current location, and relocate
 *      possibly used blocks within the current cylinder group.
 * (2)  Alternatively we can relocate the whole cylinder summary to the first
 *      new completely empty cylinder group. Once the cylinder summary is no
 *      longer in the beginning of the first cylinder group you should never
 *      use a version of fsck which is not aware of the possibility to have
 *      this structure in a non standard place.
 * Option (1) is considered to be less intrusive to the structure of the file-
 * system. So we try to stick to that whenever possible. If there is not enough
 * space in the cylinder group containing the cylinder summary we have to use
 * method (2). In case of active snapshots in the file system we probably can
 * completely avoid implementing copy on write if we stick to method (2) only.
 */
static void
updcsloc(time_t modtime, int fsi, int fso, unsigned int Nflag)
{
        DBG_FUNC("updcsloc")
        struct csum *cs;
        int ocscg, ncscg;
        int blocks;
        ufs2_daddr_t cbase, dupper, odupper, d, f, g;
        int ind, inc;
        uint cylno;
        struct gfs_bpp *bp;
        int i, l;
        int lcs = 0;
        int block;

        DBG_ENTER;

        if (howmany(sblock.fs_cssize, sblock.fs_fsize) ==
            howmany(osblock.fs_cssize, osblock.fs_fsize)) {
                /*
                 * No new fragment needed.
                 */
                DBG_LEAVE;
                return;
        }
        ocscg = dtog(&osblock, osblock.fs_csaddr);
        cs = fscs + ocscg;
        blocks = 1 + howmany(sblock.fs_cssize, sblock.fs_bsize) -
            howmany(osblock.fs_cssize, osblock.fs_bsize);

        /*
         * Read original cylinder group from disk, and make a copy.
         * XXX  If Nflag is set in some very rare cases we now miss
         *      some changes done in updjcg by reading the unmodified
         *      block from disk.
         */
        rdfs(fsbtodb(&osblock, cgtod(&osblock, ocscg)),
            (size_t)osblock.fs_cgsize, (void *)&aocg, fsi);
        DBG_PRINT0("oscg read\n");
        DBG_DUMP_CG(&sblock, "old summary cg", &aocg);

        memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));

        /*
         * Touch the cylinder group, set up local variables needed later
         * and update the superblock.
         */
        acg.cg_time = modtime;

        /*
         * XXX  In the case of having active snapshots we may need much more
         *      blocks for the copy on write. We need each block twice, and
         *      also up to 8*3 blocks for indirect blocks for all possible
         *      references.
         */
        if (/*((int)sblock.fs_time&0x3)>0||*/ cs->cs_nbfree < blocks) {
                /*
                 * There is not enough space in the old cylinder group to
                 * relocate all blocks as needed, so we relocate the whole
                 * cylinder group summary to a new group. We try to use the
                 * first complete new cylinder group just created. Within the
                 * cylinder group we align the area immediately after the
                 * cylinder group information location in order to be as
                 * close as possible to the original implementation of ffs.
                 *
                 * First we have to make sure we'll find enough space in the
                 * new cylinder group. If not, then we currently give up.
                 * We start with freeing everything which was used by the
                 * fragments of the old cylinder summary in the current group.
                 * Now we write back the group meta data, read in the needed
                 * meta data from the new cylinder group, and start allocating
                 * within that group. Here we can assume, the group to be
                 * completely empty. Which makes the handling of fragments and
                 * clusters a lot easier.
                 */
                DBG_TRC;
                if (sblock.fs_ncg - osblock.fs_ncg < 2)
                        errx(2, "panic: not enough space");

                /*
                 * Point "d" to the first fragment not used by the cylinder
                 * summary.
                 */
                d = osblock.fs_csaddr + (osblock.fs_cssize / osblock.fs_fsize);

                /*
                 * Set up last cluster size ("lcs") already here. Calculate
                 * the size for the trailing cluster just behind where "d"
                 * points to.
                 */
                if (sblock.fs_contigsumsize > 0) {
                        for (block = howmany(d % sblock.fs_fpg, sblock.fs_frag),
                            lcs = 0; lcs < sblock.fs_contigsumsize;
                            block++, lcs++) {
                                if (isclr(cg_clustersfree(&acg), block))
                                        break;
                        }
                }

                /*
                 * Point "d" to the last frag used by the cylinder summary.
                 */
                d--;

                DBG_PRINT1("d=%jd\n", (intmax_t)d);
                if ((d + 1) % sblock.fs_frag) {
                        /*
                         * The end of the cylinder summary is not a complete
                         * block.
                         */
                        DBG_TRC;
                        frag_adjust(d % sblock.fs_fpg, -1);
                        for (; (d + 1) % sblock.fs_frag; d--) {
                                DBG_PRINT1("d=%jd\n", (intmax_t)d);
                                setbit(cg_blksfree(&acg), d % sblock.fs_fpg);
                                acg.cg_cs.cs_nffree++;
                                sblock.fs_cstotal.cs_nffree++;
                        }
                        /*
                         * Point "d" to the last fragment of the last
                         * (incomplete) block of the cylinder summary.
                         */
                        d++;
                        frag_adjust(d%sblock.fs_fpg, 1);

                        if (isblock(&sblock, cg_blksfree(&acg),
                            (d % sblock.fs_fpg) / sblock.fs_frag)) {
                                DBG_PRINT1("d=%jd\n", (intmax_t)d);
                                acg.cg_cs.cs_nffree -= sblock.fs_frag;
                                acg.cg_cs.cs_nbfree++;
                                sblock.fs_cstotal.cs_nffree -= sblock.fs_frag;
                                sblock.fs_cstotal.cs_nbfree++;
                                if (sblock.fs_contigsumsize > 0) {
                                        setbit(cg_clustersfree(&acg),
                                            (d % sblock.fs_fpg) /
                                            sblock.fs_frag);
                                        if (lcs < sblock.fs_contigsumsize) {
                                                if (lcs)
                                                        cg_clustersum(&acg)[lcs]--;
                                                lcs++;
                                                cg_clustersum(&acg)[lcs]++;
                                        }
                                }
                        }
                        /*
                         * Point "d" to the first fragment of the block before
                         * the last incomplete block.
                         */
                        d--;
                }

                DBG_PRINT1("d=%jd\n", (intmax_t)d);
                for (d = rounddown(d, sblock.fs_frag); d >= osblock.fs_csaddr;
                    d -= sblock.fs_frag) {
                        DBG_TRC;
                        DBG_PRINT1("d=%jd\n", (intmax_t)d);
                        setblock(&sblock, cg_blksfree(&acg),
                            (d % sblock.fs_fpg) / sblock.fs_frag);
                        acg.cg_cs.cs_nbfree++;
                        sblock.fs_cstotal.cs_nbfree++;
                        if (sblock.fs_contigsumsize > 0) {
                                setbit(cg_clustersfree(&acg),
                                    (d % sblock.fs_fpg) / sblock.fs_frag);
                                /*
                                 * The last cluster size is already set up.
                                 */
                                if (lcs < sblock.fs_contigsumsize) {
                                        if (lcs)
                                                cg_clustersum(&acg)[lcs]--;
                                        lcs++;
                                        cg_clustersum(&acg)[lcs]++;
                                }
                        }
                }
                *cs = acg.cg_cs;

                /*
                 * Now write the former cylinder group containing the cylinder
                 * summary back to disk.
                 */
                wtfs(fsbtodb(&sblock, cgtod(&sblock, ocscg)),
                    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
                DBG_PRINT0("oscg written\n");
                DBG_DUMP_CG(&sblock, "old summary cg", &acg);

                /*
                 * Find the beginning of the new cylinder group containing the
                 * cylinder summary.
                 */
                sblock.fs_csaddr = cgdmin(&sblock, osblock.fs_ncg);
                ncscg = dtog(&sblock, sblock.fs_csaddr);
                cs = fscs + ncscg;

                /*
                 * If Nflag is specified, we would now read random data instead
                 * of an empty cg structure from disk. So we can't simulate that
                 * part for now.
                 */
                if (Nflag) {
                        DBG_PRINT0("nscg update skipped\n");
                        DBG_LEAVE;
                        return;
                }

                /*
                 * Read the future cylinder group containing the cylinder
                 * summary from disk, and make a copy.
                 */
                rdfs(fsbtodb(&sblock, cgtod(&sblock, ncscg)),
                    (size_t)sblock.fs_cgsize, (void *)&aocg, fsi);
                DBG_PRINT0("nscg read\n");
                DBG_DUMP_CG(&sblock, "new summary cg", &aocg);

                memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));

                /*
                 * Allocate all complete blocks used by the new cylinder
                 * summary.
                 */
                for (d = sblock.fs_csaddr; d + sblock.fs_frag <=
                    sblock.fs_csaddr + (sblock.fs_cssize / sblock.fs_fsize);
                    d += sblock.fs_frag) {
                        clrblock(&sblock, cg_blksfree(&acg),
                            (d % sblock.fs_fpg) / sblock.fs_frag);
                        acg.cg_cs.cs_nbfree--;
                        sblock.fs_cstotal.cs_nbfree--;
                        if (sblock.fs_contigsumsize > 0) {
                                clrbit(cg_clustersfree(&acg),
                                    (d % sblock.fs_fpg) / sblock.fs_frag);
                        }
                }

                /*
                 * Allocate all fragments used by the cylinder summary in the
                 * last block.
                 */
                if (d <
                    sblock.fs_csaddr + (sblock.fs_cssize / sblock.fs_fsize)) {
                        for (; d - sblock.fs_csaddr <
                            sblock.fs_cssize/sblock.fs_fsize; d++) {
                                clrbit(cg_blksfree(&acg), d % sblock.fs_fpg);
                                acg.cg_cs.cs_nffree--;
                                sblock.fs_cstotal.cs_nffree--;
                        }
                        acg.cg_cs.cs_nbfree--;
                        acg.cg_cs.cs_nffree += sblock.fs_frag;
                        sblock.fs_cstotal.cs_nbfree--;
                        sblock.fs_cstotal.cs_nffree += sblock.fs_frag;
                        if (sblock.fs_contigsumsize > 0)
                                clrbit(cg_clustersfree(&acg),
                                    (d % sblock.fs_fpg) / sblock.fs_frag);

                        frag_adjust(d % sblock.fs_fpg, 1);
                }
                /*
                 * XXX  Handle the cluster statistics here in the case this
                 *      cylinder group is now almost full, and the remaining
                 *      space is less then the maximum cluster size. This is
                 *      probably not needed, as you would hardly find a file
                 *      system which has only MAXCSBUFS+FS_MAXCONTIG of free
                 *      space right behind the cylinder group information in
                 *      any new cylinder group.
                 */

                /*
                 * Update our statistics in the cylinder summary.
                 */
                *cs = acg.cg_cs;

                /*
                 * Write the new cylinder group containing the cylinder summary
                 * back to disk.
                 */
                wtfs(fsbtodb(&sblock, cgtod(&sblock, ncscg)),
                    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
                DBG_PRINT0("nscg written\n");
                DBG_DUMP_CG(&sblock, "new summary cg", &acg);

                DBG_LEAVE;
                return;
        }
        /*
         * We have got enough of space in the current cylinder group, so we
         * can relocate just a few blocks, and let the summary information
         * grow in place where it is right now.
         */
        DBG_TRC;

        cbase = cgbase(&osblock, ocscg);        /* old and new are equal */
        dupper = sblock.fs_csaddr - cbase +
            howmany(sblock.fs_cssize, sblock.fs_fsize);
        odupper = osblock.fs_csaddr - cbase +
            howmany(osblock.fs_cssize, osblock.fs_fsize);

        sblock.fs_dsize -= dupper - odupper;

        /*
         * Allocate the space for the array of blocks to be relocated.
         */
        bp = (struct gfs_bpp *)malloc(((dupper - odupper) /
            sblock.fs_frag + 2) * sizeof(struct gfs_bpp));
        if (bp == NULL)
                errx(1, "malloc failed");
        memset((char *)bp, 0, ((dupper - odupper) / sblock.fs_frag + 2) *
            sizeof(struct gfs_bpp));

        /*
         * Lock all new frags needed for the cylinder group summary. This is
         * done per fragment in the first and last block of the new required
         * area, and per block for all other blocks.
         *
         * Handle the first new block here (but only if some fragments where
         * already used for the cylinder summary).
         */
        ind = 0;
        frag_adjust(odupper, -1);
        for (d = odupper; ((d < dupper) && (d % sblock.fs_frag)); d++) {
                DBG_PRINT1("scg first frag check loop d=%jd\n", (intmax_t)d);
                if (isclr(cg_blksfree(&acg), d)) {
                        if (!ind) {
                                bp[ind].old = d / sblock.fs_frag;
                                bp[ind].flags |= GFS_FL_FIRST;
                                if (roundup(d, sblock.fs_frag) >= dupper)
                                        bp[ind].flags |= GFS_FL_LAST;
                                ind++;
                        }
                } else {
                        clrbit(cg_blksfree(&acg), d);
                        acg.cg_cs.cs_nffree--;
                        sblock.fs_cstotal.cs_nffree--;
                }
                /*
                 * No cluster handling is needed here, as there was at least
                 * one fragment in use by the cylinder summary in the old
                 * file system.
                 * No block-free counter handling here as this block was not
                 * a free block.
                 */
        }
        frag_adjust(odupper, 1);

        /*
         * Handle all needed complete blocks here.
         */
        for (; d + sblock.fs_frag <= dupper; d += sblock.fs_frag) {
                DBG_PRINT1("scg block check loop d=%jd\n", (intmax_t)d);
                if (!isblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag)) {
                        for (f = d; f < d + sblock.fs_frag; f++) {
                                if (isset(cg_blksfree(&aocg), f)) {
                                        acg.cg_cs.cs_nffree--;
                                        sblock.fs_cstotal.cs_nffree--;
                                }
                        }
                        clrblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag);
                        bp[ind].old = d / sblock.fs_frag;
                        ind++;
                } else {
                        clrblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag);
                        acg.cg_cs.cs_nbfree--;
                        sblock.fs_cstotal.cs_nbfree--;
                        if (sblock.fs_contigsumsize > 0) {
                                clrbit(cg_clustersfree(&acg), d / sblock.fs_frag);
                                for (lcs = 0, l = (d / sblock.fs_frag) + 1;
                                    lcs < sblock.fs_contigsumsize; l++, lcs++ ) {
                                        if (isclr(cg_clustersfree(&acg), l))
                                                break;
                                }
                                if (lcs < sblock.fs_contigsumsize) {
                                        cg_clustersum(&acg)[lcs + 1]--;
                                        if (lcs)
                                                cg_clustersum(&acg)[lcs]++;
                                }
                        }
                }
                /*
                 * No fragment counter handling is needed here, as this finally
                 * doesn't change after the relocation.
                 */
        }

        /*
         * Handle all fragments needed in the last new affected block.
         */
        if (d < dupper) {
                frag_adjust(dupper - 1, -1);

                if (isblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag)) {
                        acg.cg_cs.cs_nbfree--;
                        sblock.fs_cstotal.cs_nbfree--;
                        acg.cg_cs.cs_nffree += sblock.fs_frag;
                        sblock.fs_cstotal.cs_nffree += sblock.fs_frag;
                        if (sblock.fs_contigsumsize > 0) {
                                clrbit(cg_clustersfree(&acg), d / sblock.fs_frag);
                                for (lcs = 0, l =(d / sblock.fs_frag) + 1;
                                    lcs < sblock.fs_contigsumsize; l++, lcs++ ) {
                                        if (isclr(cg_clustersfree(&acg),l))
                                                break;
                                }
                                if (lcs < sblock.fs_contigsumsize) {
                                        cg_clustersum(&acg)[lcs + 1]--;
                                        if (lcs)
                                                cg_clustersum(&acg)[lcs]++;
                                }
                        }
                }

                for (; d < dupper; d++) {
                        DBG_PRINT1("scg second frag check loop d=%jd\n",
                            (intmax_t)d);
                        if (isclr(cg_blksfree(&acg), d)) {
                                bp[ind].old = d / sblock.fs_frag;
                                bp[ind].flags |= GFS_FL_LAST;
                        } else {
                                clrbit(cg_blksfree(&acg), d);
                                acg.cg_cs.cs_nffree--;
                                sblock.fs_cstotal.cs_nffree--;
                        }
                }
                if (bp[ind].flags & GFS_FL_LAST) /* we have to advance here */
                        ind++;
                frag_adjust(dupper - 1, 1);
        }

        /*
         * If we found a block to relocate just do so.
         */
        if (ind) {
                for (i = 0; i < ind; i++) {
                        if (!bp[i].old) { /* no more blocks listed */
                                /*
                                 * XXX  A relative blocknumber should not be
                                 *      zero, which is not explicitly
                                 *      guaranteed by our code.
                                 */
                                break;
                        }
                        /*
                         * Allocate a complete block in the same (current)
                         * cylinder group.
                         */
                        bp[i].new = alloc() / sblock.fs_frag;

                        /*
                         * There is no frag_adjust() needed for the new block
                         * as it will have no fragments yet :-).
                         */
                        for (f = bp[i].old * sblock.fs_frag,
                            g = bp[i].new * sblock.fs_frag;
                            f < (bp[i].old + 1) * sblock.fs_frag;
                            f++, g++) {
                                if (isset(cg_blksfree(&aocg), f)) {
                                        setbit(cg_blksfree(&acg), g);
                                        acg.cg_cs.cs_nffree++;
                                        sblock.fs_cstotal.cs_nffree++;
                                }
                        }

                        /*
                         * Special handling is required if this was the first
                         * block. We have to consider the fragments which were
                         * used by the cylinder summary in the original block
                         * which re to be free in the copy of our block.  We
                         * have to be careful if this first block happens to
                         * be also the last block to be relocated.
                         */
                        if (bp[i].flags & GFS_FL_FIRST) {
                                for (f = bp[i].old * sblock.fs_frag,
                                    g =bp[i].new * sblock.fs_frag;
                                    f < odupper; f++, g++) {
                                        setbit(cg_blksfree(&acg), g);
                                        acg.cg_cs.cs_nffree++;
                                        sblock.fs_cstotal.cs_nffree++;
                                }
                                if (!(bp[i].flags & GFS_FL_LAST))
                                        frag_adjust(bp[i].new * sblock.fs_frag, 1);
                        }

                        /*
                         * Special handling is required if this is the last
                         * block to be relocated.
                         */
                        if (bp[i].flags & GFS_FL_LAST) {
                                frag_adjust(bp[i].new * sblock.fs_frag, 1);
                                frag_adjust(bp[i].old * sblock.fs_frag, -1);
                                for (f = dupper;
                                    f < roundup(dupper, sblock.fs_frag); f++) {
                                        if (isclr(cg_blksfree(&acg), f)) {
                                                setbit(cg_blksfree(&acg), f);
                                                acg.cg_cs.cs_nffree++;
                                                sblock.fs_cstotal.cs_nffree++;
                                        }
                                }
                                frag_adjust(bp[i].old * sblock.fs_frag, 1);
                        }

                        /*
                         * !!! Attach the cylindergroup offset here.
                         */
                        bp[i].old += cbase / sblock.fs_frag;
                        bp[i].new += cbase / sblock.fs_frag;

                        /*
                         * Copy the content of the block.
                         */
                        /*
                         * XXX  Here we will have to implement a copy on write
                         *      in the case we have any active snapshots.
                         */
                        rdfs(fsbtodb(&sblock, bp[i].old * sblock.fs_frag),
                            (size_t)sblock.fs_bsize, (void *)&ablk, fsi);
                        wtfs(fsbtodb(&sblock, bp[i].new * sblock.fs_frag),
                            (size_t)sblock.fs_bsize, (void *)&ablk, fso, Nflag);
                        DBG_DUMP_HEX(&sblock, "copied full block",
                            (unsigned char *)&ablk);
                        DBG_PRINT2("scg (%jd->%jd) block relocated\n",
                            (intmax_t)bp[i].old, (intmax_t)bp[i].new);
                }

                /*
                 * Now we have to update all references to any fragment which
                 * belongs to any block relocated. We iterate now over all
                 * cylinder groups, within those over all non zero length
                 * inodes.
                 */
                for (cylno = 0; cylno < osblock.fs_ncg; cylno++) {
                        DBG_PRINT1("scg doing cg (%d)\n", cylno);
                        for (inc = osblock.fs_ipg - 1 ; inc > 0 ; inc--)
                                updrefs(cylno, (ino_t)inc, bp, fsi, fso, Nflag);
                }

                /*
                 * All inodes are checked, now make sure the number of
                 * references found make sense.
                 */
                for (i = 0; i < ind; i++) {
                        if (!bp[i].found || (bp[i].found > sblock.fs_frag)) {
                                warnx("error: %jd refs found for block %jd.",
                                    (intmax_t)bp[i].found, (intmax_t)bp[i].old);
                        }
                }
        }
        /*
         * The following statistics are not changed here:
         *     sblock.fs_cstotal.cs_ndir
         *     sblock.fs_cstotal.cs_nifree
         * The following statistics were already updated on the fly:
         *     sblock.fs_cstotal.cs_nffree
         *     sblock.fs_cstotal.cs_nbfree
         * As the statistics for this cylinder group are ready, copy it to
         * the summary information array.
         */

        *cs = acg.cg_cs;

        /*
         * Write summary cylinder group back to disk.
         */
        wtfs(fsbtodb(&sblock, cgtod(&sblock, ocscg)), (size_t)sblock.fs_cgsize,
            (void *)&acg, fso, Nflag);
        DBG_PRINT0("scg written\n");
        DBG_DUMP_CG(&sblock, "new summary cg", &acg);

        DBG_LEAVE;
        return;
}

/*
 * Here we read some block(s) from disk.
 */
static void
rdfs(ufs2_daddr_t bno, size_t size, void *bf, int fsi)
{
        DBG_FUNC("rdfs")
        ssize_t n;

        DBG_ENTER;

        if (bno < 0)
                err(32, "rdfs: attempting to read negative block number");
        if (lseek(fsi, (off_t)bno * DEV_BSIZE, 0) < 0)
                err(33, "rdfs: seek error: %jd", (intmax_t)bno);
        n = read(fsi, bf, size);
        if (n != (ssize_t)size)
                err(34, "rdfs: read error: %jd", (intmax_t)bno);

        DBG_LEAVE;
        return;
}

/*
 * Here we write some block(s) to disk.
 */
static void
wtfs(ufs2_daddr_t bno, size_t size, void *bf, int fso, unsigned int Nflag)
{
        DBG_FUNC("wtfs")
        ssize_t n;

        DBG_ENTER;

        if (Nflag) {
                DBG_LEAVE;
                return;
        }
        if (lseek(fso, (off_t)bno * DEV_BSIZE, SEEK_SET) < 0)
                err(35, "wtfs: seek error: %ld", (long)bno);
        n = write(fso, bf, size);
        if (n != (ssize_t)size)
                err(36, "wtfs: write error: %ld", (long)bno);

        DBG_LEAVE;
        return;
}

/*
 * Here we allocate a free block in the current cylinder group. It is assumed,
 * that acg contains the current cylinder group. As we may take a block from
 * somewhere in the file system we have to handle cluster summary here.
 */
static ufs2_daddr_t
alloc(void)
{
        DBG_FUNC("alloc")
        ufs2_daddr_t d, blkno;
        int lcs1, lcs2;
        int l;
        int csmin, csmax;
        int dlower, dupper, dmax;

        DBG_ENTER;

        if (acg.cg_magic != CG_MAGIC) {
                warnx("acg: bad magic number");
                DBG_LEAVE;
                return (0);
        }
        if (acg.cg_cs.cs_nbfree == 0) {
                warnx("error: cylinder group ran out of space");
                DBG_LEAVE;
                return (0);
        }
        /*
         * We start seeking for free blocks only from the space available after
         * the end of the new grown cylinder summary. Otherwise we allocate a
         * block here which we have to relocate a couple of seconds later again
         * again, and we are not prepared to to this anyway.
         */
        blkno = -1;
        dlower = cgsblock(&sblock, acg.cg_cgx) - cgbase(&sblock, acg.cg_cgx);
        dupper = cgdmin(&sblock, acg.cg_cgx) - cgbase(&sblock, acg.cg_cgx);
        dmax = cgbase(&sblock, acg.cg_cgx) + sblock.fs_fpg;
        if (dmax > sblock.fs_size)
                dmax = sblock.fs_size;
        dmax -= cgbase(&sblock, acg.cg_cgx); /* retransform into cg */
        csmin = sblock.fs_csaddr - cgbase(&sblock, acg.cg_cgx);
        csmax = csmin + howmany(sblock.fs_cssize, sblock.fs_fsize);
        DBG_PRINT3("seek range: dl=%d, du=%d, dm=%d\n", dlower, dupper, dmax);
        DBG_PRINT2("range cont: csmin=%d, csmax=%d\n", csmin, csmax);

        for (d = 0; (d < dlower && blkno == -1); d += sblock.fs_frag) {
                if (d >= csmin && d <= csmax)
                        continue;
                if (isblock(&sblock, cg_blksfree(&acg), fragstoblks(&sblock, d))) {
                        blkno = fragstoblks(&sblock, d);/* Yeah found a block */
                        break;
                }
        }
        for (d = dupper; (d < dmax && blkno == -1); d += sblock.fs_frag) {
                if (d >= csmin && d <= csmax) {
                        continue;
                }
                if (isblock(&sblock, cg_blksfree(&acg), fragstoblks(&sblock, d))) {
                        blkno = fragstoblks(&sblock, d);/* Yeah found a block */
                        break;
                }
        }
        if (blkno == -1) {
                warnx("internal error: couldn't find promised block in cg");
                DBG_LEAVE;
                return (0);
        }

        /*
         * This is needed if the block was found already in the first loop.
         */
        d = blkstofrags(&sblock, blkno);

        clrblock(&sblock, cg_blksfree(&acg), blkno);
        if (sblock.fs_contigsumsize > 0) {
                /*
                 * Handle the cluster allocation bitmap.
                 */
                clrbit(cg_clustersfree(&acg), blkno);
                /*
                 * We possibly have split a cluster here, so we have to do
                 * recalculate the sizes of the remaining cluster halves now,
                 * and use them for updating the cluster summary information.
                 *
                 * Lets start with the blocks before our allocated block ...
                 */
                for (lcs1 = 0, l = blkno - 1; lcs1 < sblock.fs_contigsumsize;
                                l--, lcs1++ ) {
                        if (isclr(cg_clustersfree(&acg), l))
                                break;
                }
                /*
                 * ... and continue with the blocks right after our allocated
                 * block.
                 */
                for (lcs2 = 0, l = blkno + 1; lcs2 < sblock.fs_contigsumsize;
                    l++, lcs2++ ) {
                        if (isclr(cg_clustersfree(&acg), l))
                                break;
                }

                /*
                 * Now update all counters.
                 */
                cg_clustersum(&acg)[MIN(lcs1 + lcs2 + 1, sblock.fs_contigsumsize)]--;
                if (lcs1)
                        cg_clustersum(&acg)[lcs1]++;
                if (lcs2)
                        cg_clustersum(&acg)[lcs2]++;
        }
        /*
         * Update all statistics based on blocks.
         */
        acg.cg_cs.cs_nbfree--;
        sblock.fs_cstotal.cs_nbfree--;

        DBG_LEAVE;
        return (d);
}

/*
 * Here we check if all frags of a block are free. For more details again
 * please see the source of newfs(8), as this function is taken over almost
 * unchanged.
 */
static int
isblock(struct fs *fs, unsigned char *cp, int h)
{
        DBG_FUNC("isblock")
        unsigned char mask;

        DBG_ENTER;

        switch (fs->fs_frag) {
        case 8:
                DBG_LEAVE;
                return (cp[h] == 0xff);
        case 4:
                mask = 0x0f << ((h & 0x1) << 2);
                DBG_LEAVE;
                return ((cp[h >> 1] & mask) == mask);
        case 2:
                mask = 0x03 << ((h & 0x3) << 1);
                DBG_LEAVE;
                return ((cp[h >> 2] & mask) == mask);
        case 1:
                mask = 0x01 << (h & 0x7);
                DBG_LEAVE;
                return ((cp[h >> 3] & mask) == mask);
        default:
                fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag);
                DBG_LEAVE;
                return (0);
        }
}

/*
 * Here we allocate a complete block in the block map. For more details again
 * please see the source of newfs(8), as this function is taken over almost
 * unchanged.
 */
static void
clrblock(struct fs *fs, unsigned char *cp, int h)
{
        DBG_FUNC("clrblock")

        DBG_ENTER;

        switch ((fs)->fs_frag) {
        case 8:
                cp[h] = 0;
                break;
        case 4:
                cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
                break;
        case 2:
                cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
                break;
        case 1:
                cp[h >> 3] &= ~(0x01 << (h & 0x7));
                break;
        default:
                warnx("clrblock bad fs_frag %d", fs->fs_frag);
                break;
        }

        DBG_LEAVE;
        return;
}

/*
 * Here we free a complete block in the free block map. For more details again
 * please see the source of newfs(8), as this function is taken over almost
 * unchanged.
 */
static void
setblock(struct fs *fs, unsigned char *cp, int h)
{
        DBG_FUNC("setblock")

        DBG_ENTER;

        switch (fs->fs_frag) {
        case 8:
                cp[h] = 0xff;
                break;
        case 4:
                cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
                break;
        case 2:
                cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
                break;
        case 1:
                cp[h >> 3] |= (0x01 << (h & 0x7));
                break;
        default:
                warnx("setblock bad fs_frag %d", fs->fs_frag);
                break;
        }

        DBG_LEAVE;
        return;
}

/*
 * This function provides access to an individual inode. We find out in which
 * block the requested inode is located, read it from disk if needed, and
 * return the pointer into that block. We maintain a cache of one block to
 * not read the same block again and again if we iterate linearly over all
 * inodes.
 */
static union dinode *
ginode(ino_t inumber, int fsi, int cg)
{
        DBG_FUNC("ginode")
        static ino_t startinum = 0;     /* first inode in cached block */

        DBG_ENTER;

        /*
         * The inumber passed in is relative to the cg, so use it here to see
         * if the inode has been allocated yet.
         */
        if (isclr(cg_inosused(&aocg), inumber)) {
                DBG_LEAVE;
                return NULL;
        }
        /*
         * Now make the inumber relative to the entire inode space so it can
         * be sanity checked.
         */
        inumber += (cg * sblock.fs_ipg);
        if (inumber < ROOTINO) {
                DBG_LEAVE;
                return NULL;
        }
        if (inumber > maxino)
                errx(8, "bad inode number %d to ginode", inumber);
        if (startinum == 0 ||
            inumber < startinum || inumber >= startinum + INOPB(&sblock)) {
                inoblk = fsbtodb(&sblock, ino_to_fsba(&sblock, inumber));
                rdfs(inoblk, (size_t)sblock.fs_bsize, inobuf, fsi);
                startinum = (inumber / INOPB(&sblock)) * INOPB(&sblock);
        }
        DBG_LEAVE;
        if (sblock.fs_magic == FS_UFS1_MAGIC)
                return (union dinode *)((uintptr_t)inobuf +
                    (inumber % INOPB(&sblock)) * sizeof(struct ufs1_dinode));
        return (union dinode *)((uintptr_t)inobuf +
            (inumber % INOPB(&sblock)) * sizeof(struct ufs2_dinode));
}

/*
 * Figure out how many lines our current terminal has. For more details again
 * please see the source of newfs(8), as this function is taken over almost
 * unchanged.
 */
static int
charsperline(void)
{
        DBG_FUNC("charsperline")
        int columns;
        char *cp;
        struct winsize ws;

        DBG_ENTER;

        columns = 0;
        if (ioctl(0, TIOCGWINSZ, &ws) != -1)
                columns = ws.ws_col;
        if (columns == 0 && (cp = getenv("COLUMNS")))
                columns = atoi(cp);
        if (columns == 0)
                columns = 80;   /* last resort */

        DBG_LEAVE;
        return columns;
}

/*
 * Get the size of the partition if we can't figure it out from the disklabel,
 * e.g. from vinum volumes.
 */
static void
get_dev_size(int fd, int *size)
{
        int sectorsize;
        off_t mediasize;

        if (ioctl(fd, DIOCGSECTORSIZE, &sectorsize) == -1)
                err(1,"DIOCGSECTORSIZE");
        if (ioctl(fd, DIOCGMEDIASIZE, &mediasize) == -1)
                err(1,"DIOCGMEDIASIZE");

        if (sectorsize <= 0)
                errx(1, "bogus sectorsize: %d", sectorsize);

        *size = mediasize / sectorsize;
}

/*
 * growfs(8) is a utility which allows to increase the size of an existing
 * ufs file system. Currently this can only be done on unmounted file system.
 * It recognizes some command line options to specify the new desired size,
 * and it does some basic checkings. The old file system size is determined
 * and after some more checks like we can really access the new last block
 * on the disk etc. we calculate the new parameters for the superblock. After
 * having done this we just call growfs() which will do the work.  Before
 * we finish the only thing left is to update the disklabel.
 * We still have to provide support for snapshots. Therefore we first have to
 * understand what data structures are always replicated in the snapshot on
 * creation, for all other blocks we touch during our procedure, we have to
 * keep the old blocks unchanged somewhere available for the snapshots. If we
 * are lucky, then we only have to handle our blocks to be relocated in that
 * way.
 * Also we have to consider in what order we actually update the critical
 * data structures of the file system to make sure, that in case of a disaster
 * fsck(8) is still able to restore any lost data.
 * The foreseen last step then will be to provide for growing even mounted
 * file systems. There we have to extend the mount() system call to provide
 * userland access to the file system locking facility.
 */
int
main(int argc, char **argv)
{
        DBG_FUNC("main")
        char *device, *special, *cp;
        int ch;
        unsigned int size = 0;
        size_t len;
        unsigned int Nflag = 0;
        int ExpertFlag = 0;
        struct stat st;
        struct disklabel *lp;
        struct partition *pp;
        int i, fsi, fso;
        u_int32_t p_size;
        char reply[5];
#ifdef FSMAXSNAP
        int j;
#endif /* FSMAXSNAP */

        DBG_ENTER;

        while ((ch = getopt(argc, argv, "Ns:vy")) != -1) {
                switch(ch) {
                case 'N':
                        Nflag = 1;
                        break;
                case 's':
                        size = (size_t)atol(optarg);
                        if (size < 1)
                                usage();
                        break;
                case 'v': /* for compatibility to newfs */
                        break;
                case 'y':
                        ExpertFlag = 1;
                        break;
                case '?':
                        /* FALLTHROUGH */
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;

        if (argc != 1)
                usage();

        device = *argv;

        /*
         * Now try to guess the (raw)device name.
         */
        if (0 == strrchr(device, '/')) {
                /*
                 * No path prefix was given, so try in that order:
                 *     /dev/r%s
                 *     /dev/%s
                 *     /dev/vinum/r%s
                 *     /dev/vinum/%s.
                 *
                 * FreeBSD now doesn't distinguish between raw and block
                 * devices any longer, but it should still work this way.
                 */
                len = strlen(device) + strlen(_PATH_DEV) + 2 + strlen("vinum/");
                special = (char *)malloc(len);
                if (special == NULL)
                        errx(1, "malloc failed");
                snprintf(special, len, "%sr%s", _PATH_DEV, device);
                if (stat(special, &st) == -1) {
                        snprintf(special, len, "%s%s", _PATH_DEV, device);
                        if (stat(special, &st) == -1) {
                                snprintf(special, len, "%svinum/r%s",
                                    _PATH_DEV, device);
                                if (stat(special, &st) == -1) {
                                        /* For now this is the 'last resort' */
                                        snprintf(special, len, "%svinum/%s",
                                            _PATH_DEV, device);
                                }
                        }
                }
                device = special;
        }

        /*
         * Try to access our devices for writing ...
         */
        if (Nflag) {
                fso = -1;
        } else {
                fso = open(device, O_WRONLY);
                if (fso < 0)
                        err(1, "%s", device);
        }

        /*
         * ... and reading.
         */
        fsi = open(device, O_RDONLY);
        if (fsi < 0)
                err(1, "%s", device);

        /*
         * Try to read a label and guess the slice if not specified. This
         * code should guess the right thing and avoid to bother the user
         * with the task of specifying the option -v on vinum volumes.
         */
        cp = device + strlen(device) - 1;
        lp = get_disklabel(fsi);
        pp = NULL;
        if (lp != NULL) {
                if (isdigit(*cp))
                        pp = &lp->d_partitions[2];
                else if (*cp>='a' && *cp<='h')
                        pp = &lp->d_partitions[*cp - 'a'];
                else
                        errx(1, "unknown device");
                p_size = pp->p_size;
        } else {
                get_dev_size(fsi, &p_size);
        }

        /*
         * Check if that partition is suitable for growing a file system.
         */
        if (p_size < 1)
                errx(1, "partition is unavailable");

        /*
         * Read the current superblock, and take a backup.
         */
        for (i = 0; sblock_try[i] != -1; i++) {
                sblockloc = sblock_try[i] / DEV_BSIZE;
                rdfs(sblockloc, (size_t)SBLOCKSIZE, (void *)&(osblock), fsi);
                if ((osblock.fs_magic == FS_UFS1_MAGIC ||
                    (osblock.fs_magic == FS_UFS2_MAGIC &&
                    osblock.fs_sblockloc == sblock_try[i])) &&
                    osblock.fs_bsize <= MAXBSIZE &&
                    osblock.fs_bsize >= (int32_t) sizeof(struct fs))
                        break;
        }
        if (sblock_try[i] == -1)
                errx(1, "superblock not recognized");
        memcpy((void *)&fsun1, (void *)&fsun2, sizeof(fsun2));
        maxino = sblock.fs_ncg * sblock.fs_ipg;

        DBG_OPEN("/tmp/growfs.debug"); /* already here we need a superblock */
        DBG_DUMP_FS(&sblock, "old sblock");

        /*
         * Determine size to grow to. Default to the full size specified in
         * the disk label.
         */
        sblock.fs_size = dbtofsb(&osblock, p_size);
        if (size != 0) {
                if (size > p_size)
                        errx(1, "there is not enough space (%d < %d)",
                            p_size, size);
                sblock.fs_size = dbtofsb(&osblock, size);
        }

        /*
         * Are we really growing ?
         */
        if (osblock.fs_size >= sblock.fs_size) {
                errx(1, "we are not growing (%jd->%jd)",
                    (intmax_t)osblock.fs_size, (intmax_t)sblock.fs_size);
        }


#ifdef FSMAXSNAP
        /*
         * Check if we find an active snapshot.
         */
        if (ExpertFlag == 0) {
                for (j = 0; j < FSMAXSNAP; j++) {
                        if (sblock.fs_snapinum[j]) {
                                errx(1, "active snapshot found in file system; "
                                    "please remove all snapshots before "
                                    "using growfs");
                        }
                        if (!sblock.fs_snapinum[j]) /* list is dense */
                                break;
                }
        }
#endif

        if (ExpertFlag == 0 && Nflag == 0) {
                printf("We strongly recommend you to make a backup "
                    "before growing the file system.\n"
                    "Did you backup your data (Yes/No)? ");
                fgets(reply, (int)sizeof(reply), stdin);
                if (strcmp(reply, "Yes\n")){
                        printf("\nNothing done\n");
                        exit (0);
                }
        }

        printf("New file system size is %jd frags\n", (intmax_t)sblock.fs_size);

        /*
         * Try to access our new last block in the file system. Even if we
         * later on realize we have to abort our operation, on that block
         * there should be no data, so we can't destroy something yet.
         */
        wtfs((ufs2_daddr_t)p_size - 1, (size_t)DEV_BSIZE, (void *)&sblock,
            fso, Nflag);

        /*
         * Now calculate new superblock values and check for reasonable
         * bound for new file system size:
         *     fs_size:    is derived from label or user input
         *     fs_dsize:   should get updated in the routines creating or
         *                 updating the cylinder groups on the fly
         *     fs_cstotal: should get updated in the routines creating or
         *                 updating the cylinder groups
         */

        /*
         * Update the number of cylinders and cylinder groups in the file system.
         */
        if (sblock.fs_magic == FS_UFS1_MAGIC) {
                sblock.fs_old_ncyl =
                    sblock.fs_size * sblock.fs_old_nspf / sblock.fs_old_spc;
                if (sblock.fs_size * sblock.fs_old_nspf >
                    sblock.fs_old_ncyl * sblock.fs_old_spc)
                        sblock.fs_old_ncyl++;
        }
        sblock.fs_ncg = howmany(sblock.fs_size, sblock.fs_fpg);
        maxino = sblock.fs_ncg * sblock.fs_ipg;

        if (sblock.fs_size % sblock.fs_fpg != 0 &&
            sblock.fs_size % sblock.fs_fpg < cgdmin(&sblock, sblock.fs_ncg)) {
                /*
                 * The space in the new last cylinder group is too small,
                 * so revert back.
                 */
                sblock.fs_ncg--;
                if (sblock.fs_magic == FS_UFS1_MAGIC)
                        sblock.fs_old_ncyl = sblock.fs_ncg * sblock.fs_old_cpg;
                printf("Warning: %jd sector(s) cannot be allocated.\n",
                    (intmax_t)fsbtodb(&sblock, sblock.fs_size % sblock.fs_fpg));
                sblock.fs_size = sblock.fs_ncg * sblock.fs_fpg;
                maxino -= sblock.fs_ipg;
        }

        /*
         * Update the space for the cylinder group summary information in the
         * respective cylinder group data area.
         */
        sblock.fs_cssize =
            fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));

        if (osblock.fs_size >= sblock.fs_size)
                errx(1, "not enough new space");

        DBG_PRINT0("sblock calculated\n");

        /*
         * Ok, everything prepared, so now let's do the tricks.
         */
        growfs(fsi, fso, Nflag);

        /*
         * Update the disk label.
         */
        if (!unlabeled) {
                pp->p_fsize = sblock.fs_fsize;
                pp->p_frag = sblock.fs_frag;
                pp->p_cpg = sblock.fs_fpg;

                return_disklabel(fso, lp, Nflag);
                DBG_PRINT0("label rewritten\n");
        }

        close(fsi);
        if (fso > -1)
                close(fso);

        DBG_CLOSE;

        DBG_LEAVE;
        return 0;
}

/*
 * Write the updated disklabel back to disk.
 */
static void
return_disklabel(int fd, struct disklabel *lp, unsigned int Nflag)
{
        DBG_FUNC("return_disklabel")
        u_short sum;
        u_short *ptr;

        DBG_ENTER;

        if (!lp) {
                DBG_LEAVE;
                return;
        }
        if (!Nflag) {
                lp->d_checksum = 0;
                sum = 0;
                ptr = (u_short *)lp;

                /*
                 * recalculate checksum
                 */
                while (ptr < (u_short *)&lp->d_partitions[lp->d_npartitions])
                        sum ^= *ptr++;
                lp->d_checksum=sum;

                if (ioctl(fd, DIOCWDINFO, (char *)lp) < 0)
                        errx(1, "DIOCWDINFO failed");
        }
        free(lp);

        DBG_LEAVE;
        return ;
}

/*
 * Read the disklabel from disk.
 */
static struct disklabel *
get_disklabel(int fd)
{
        DBG_FUNC("get_disklabel")
        static struct disklabel *lab;

        DBG_ENTER;

        lab = (struct disklabel *)malloc(sizeof(struct disklabel));
        if (!lab)
                errx(1, "malloc failed");

        if (!ioctl(fd, DIOCGDINFO, (char *)lab))
                return (lab);

        unlabeled++;

        DBG_LEAVE;
        return (NULL);
}


/*
 * Dump a line of usage.
 */
static void
usage(void)
{
        DBG_FUNC("usage")

        DBG_ENTER;

        fprintf(stderr, "usage: growfs [-Ny] [-s size] special\n");

        DBG_LEAVE;
        exit(1);
}

/*
 * This updates most parameters and the bitmap related to cluster. We have to
 * assume that sblock, osblock, acg are set up.
 */
static void
updclst(int block)
{
        DBG_FUNC("updclst")
        static int lcs = 0;

        DBG_ENTER;

        if (sblock.fs_contigsumsize < 1) /* no clustering */
                return;
        /*
         * update cluster allocation map
         */
        setbit(cg_clustersfree(&acg), block);

        /*
         * update cluster summary table
         */
        if (!lcs) {
                /*
                 * calculate size for the trailing cluster
                 */
                for (block--; lcs < sblock.fs_contigsumsize; block--, lcs++ ) {
                        if (isclr(cg_clustersfree(&acg), block))
                                break;
                }
        }
        if (lcs < sblock.fs_contigsumsize) {
                if (lcs)
                        cg_clustersum(&acg)[lcs]--;
                lcs++;
                cg_clustersum(&acg)[lcs]++;
        }

        DBG_LEAVE;
        return;
}

/*
 * This updates all references to relocated blocks for the given inode.  The
 * inode is given as number within the cylinder group, and the number of the
 * cylinder group.
 */
static void
updrefs(int cg, ino_t in, struct gfs_bpp *bp, int fsi, int fso, unsigned int
    Nflag)
{
        DBG_FUNC("updrefs")
        ufs_lbn_t len, lbn, numblks;
        ufs2_daddr_t iptr, blksperindir;
        union dinode *ino;
        int i, mode, inodeupdated;

        DBG_ENTER;

        ino = ginode(in, fsi, cg);
        if (ino == NULL) {
                DBG_LEAVE;
                return;
        }
        mode = DIP(ino, di_mode) & IFMT;
        if (mode != IFDIR && mode != IFREG && mode != IFLNK) {
                DBG_LEAVE;
                return; /* only check DIR, FILE, LINK */
        }
        if (mode == IFLNK && 
            DIP(ino, di_size) < (u_int64_t) sblock.fs_maxsymlinklen) {
                DBG_LEAVE;
                return; /* skip short symlinks */
        }
        numblks = howmany(DIP(ino, di_size), sblock.fs_bsize);
        if (numblks == 0) {
                DBG_LEAVE;
                return; /* skip empty file */
        }
        if (DIP(ino, di_blocks) == 0) {
                DBG_LEAVE;
                return; /* skip empty swiss cheesy file or old fastlink */
        }
        DBG_PRINT2("scg checking inode (%d in %d)\n", in, cg);

        /*
         * Check all the blocks.
         */
        inodeupdated = 0;
        len = numblks < NDADDR ? numblks : NDADDR;
        for (i = 0; i < len; i++) {
                iptr = DIP(ino, di_db[i]);
                if (iptr == 0)
                        continue;
                if (cond_bl_upd(&iptr, bp, fsi, fso, Nflag)) {
                        DIP_SET(ino, di_db[i], iptr);
                        inodeupdated++;
                }
        }
        DBG_PRINT0("~~scg direct blocks checked\n");

        blksperindir = 1;
        len = numblks - NDADDR;
        lbn = NDADDR;
        for (i = 0; len > 0 && i < NIADDR; i++) {
                iptr = DIP(ino, di_ib[i]);
                if (iptr == 0)
                        continue;
                if (cond_bl_upd(&iptr, bp, fsi, fso, Nflag)) {
                        DIP_SET(ino, di_ib[i], iptr);
                        inodeupdated++;
                }
                indirchk(blksperindir, lbn, iptr, numblks, bp, fsi, fso, Nflag);
                blksperindir *= NINDIR(&sblock);
                lbn += blksperindir;
                len -= blksperindir;
                DBG_PRINT1("scg indirect_%d blocks checked\n", i + 1);
        }
        if (inodeupdated)
                wtfs(inoblk, sblock.fs_bsize, inobuf, fso, Nflag);

        DBG_LEAVE;
        return;
}

/*
 * Recursively check all the indirect blocks.
 */
static void
indirchk(ufs_lbn_t blksperindir, ufs_lbn_t lbn, ufs2_daddr_t blkno,
    ufs_lbn_t lastlbn, struct gfs_bpp *bp, int fsi, int fso, unsigned int Nflag)
{
        DBG_FUNC("indirchk")
        void *ibuf;
        int i, last;
        ufs2_daddr_t iptr;

        DBG_ENTER;

        /* read in the indirect block. */
        ibuf = malloc(sblock.fs_bsize);
        if (!ibuf)
                errx(1, "malloc failed");
        rdfs(fsbtodb(&sblock, blkno), (size_t)sblock.fs_bsize, ibuf, fsi);
        last = howmany(lastlbn - lbn, blksperindir) < NINDIR(&sblock) ?
            howmany(lastlbn - lbn, blksperindir) : NINDIR(&sblock);
        for (i = 0; i < last; i++) {
                if (sblock.fs_magic == FS_UFS1_MAGIC)
                        iptr = ((ufs1_daddr_t *)ibuf)[i];
                else
                        iptr = ((ufs2_daddr_t *)ibuf)[i];
                if (iptr == 0)
                        continue;
                if (cond_bl_upd(&iptr, bp, fsi, fso, Nflag)) {
                        if (sblock.fs_magic == FS_UFS1_MAGIC)
                                ((ufs1_daddr_t *)ibuf)[i] = iptr;
                        else
                                ((ufs2_daddr_t *)ibuf)[i] = iptr;
                }
                if (blksperindir == 1)
                        continue;
                indirchk(blksperindir / NINDIR(&sblock), lbn + blksperindir * i,
                    iptr, lastlbn, bp, fsi, fso, Nflag);
        }
        free(ibuf);

        DBG_LEAVE;
        return;
}