xref: /csrg-svn/sbin/fsck/setup.c (revision 30399)

/*
 * Copyright (c) 1980 Regents of the University of California.
 * All rights reserved.  The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */

#ifndef lint
static char sccsid[] = "@(#)setup.c	5.4 (Berkeley) 01/15/87";
#endif not lint

#define DKTYPENAMES
#include <sys/param.h>
#include <sys/inode.h>
#include <sys/fs.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <sys/disklabel.h>
#include <sys/file.h>
#include <ctype.h>
#include "fsck.h"

#define POWEROF2(num)	(((num) & ((num) - 1)) == 0)

char	*calloc();
char	*index();

setup(dev)
	char *dev;
{
	dev_t rootdev;
	long cg, ncg, size, i, j;
	struct stat statb;
	struct fs proto;

	if (stat("/", &statb) < 0)
		errexit("Can't stat root\n");
	rootdev = statb.st_dev;
	if (stat(dev, &statb) < 0) {
		printf("Can't stat %s\n", dev);
		return (0);
	}
	rawflg = 0;
	if ((statb.st_mode & S_IFMT) == S_IFBLK)
		;
	else if ((statb.st_mode & S_IFMT) == S_IFCHR)
		rawflg++;
	else {
		if (reply("file is not a block or character device; OK") == 0)
			return (0);
	}
	if (rootdev == statb.st_rdev)
		hotroot++;
	if ((dfile.rfdes = open(dev, O_RDONLY)) < 0) {
		printf("Can't open %s\n", dev);
		return (0);
	}
	if (preen == 0)
		printf("** %s", dev);
	if (nflag || (dfile.wfdes = open(dev, O_WRONLY)) < 0) {
		dfile.wfdes = -1;
		if (preen)
			pfatal("NO WRITE ACCESS");
		printf(" (NO WRITE)");
	}
	if (preen == 0)
		printf("\n");
	dfile.mod = 0;
	lfdir = 0;
	initbarea(&sblk);
	initbarea(&fileblk);
	initbarea(&inoblk);
	initbarea(&cgblk);
	/*
	 * Read in the superblock, looking for alternates if necessary
	 */
	if (readsb(1) == 0) {
		if (bflag || calcsb(dev, dfile.rfdes, &proto) == 0 || preen)
			return(0);
		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
			return (0);
		for (cg = 0; cg < proto.fs_ncg; cg++) {
			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
			if (readsb(0) != 0)
				break;
		}
		if (cg >= proto.fs_ncg) {
			printf("%s %s\n%s %s\n%s %s\n",
				"SEARCH FOR ALTERNATE SUPER-BLOCK",
				"FAILED. YOU MUST USE THE",
				"-b OPTION TO FSCK TO SPECIFY THE",
				"LOCATION OF AN ALTERNATE",
				"SUPER-BLOCK TO SUPPLY NEEDED",
				"INFORMATION; SEE fsck(8).");
			return(0);
		}
		pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag);
	}
	fmax = sblock.fs_size;
	imax = sblock.fs_ncg * sblock.fs_ipg;
	/*
	 * Check and potentially fix certain fields in the super block.
	 */
	if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
		if (reply("SET TO DEFAULT") == 1) {
			sblock.fs_optim = FS_OPTTIME;
			sbdirty();
		}
	}
	if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
			sblock.fs_minfree);
		if (reply("SET TO DEFAULT") == 1) {
			sblock.fs_minfree = 10;
			sbdirty();
		}
	}
	/*
	 * read in the summary info.
	 */
	for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
		size = sblock.fs_cssize - i < sblock.fs_bsize ?
		    sblock.fs_cssize - i : sblock.fs_bsize;
		sblock.fs_csp[j] = (struct csum *)calloc(1, (unsigned)size);
		if (bread(&dfile, (char *)sblock.fs_csp[j],
		    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
		    size) != 0)
			return (0);
	}
	/*
	 * allocate and initialize the necessary maps
	 */
	bmapsz = roundup(howmany(fmax, NBBY), sizeof(short));
	blockmap = calloc((unsigned)bmapsz, sizeof (char));
	if (blockmap == NULL) {
		printf("cannot alloc %d bytes for blockmap\n", bmapsz);
		goto badsb;
	}
	statemap = calloc((unsigned)(imax + 1), sizeof(char));
	if (statemap == NULL) {
		printf("cannot alloc %d bytes for statemap\n", imax + 1);
		goto badsb;
	}
	lncntp = (short *)calloc((unsigned)(imax + 1), sizeof(short));
	if (lncntp == NULL) {
		printf("cannot alloc %d bytes for lncntp\n",
		    (imax + 1) * sizeof(short));
		goto badsb;
	}

	return (1);

badsb:
	ckfini();
	return (0);
}

/*
 * Read in the super block and its summary info.
 */
readsb(listerr)
	int listerr;
{
	BUFAREA asblk;
#	define altsblock asblk.b_un.b_fs
	daddr_t super = bflag ? bflag : SBLOCK;

	initbarea(&asblk);
	if (bread(&dfile, (char *)&sblock, super, (long)SBSIZE) != 0)
		return (0);
	sblk.b_bno = super;
	sblk.b_size = SBSIZE;
	/*
	 * run a few consistency checks of the super block
	 */
	if (sblock.fs_magic != FS_MAGIC)
		{ badsb(listerr, "MAGIC NUMBER WRONG"); return (0); }
	if (sblock.fs_ncg < 1)
		{ badsb(listerr, "NCG OUT OF RANGE"); return (0); }
	if (sblock.fs_cpg < 1 || sblock.fs_cpg > MAXCPG)
		{ badsb(listerr, "CPG OUT OF RANGE"); return (0); }
	if (sblock.fs_ncg * sblock.fs_cpg < sblock.fs_ncyl ||
	    (sblock.fs_ncg - 1) * sblock.fs_cpg >= sblock.fs_ncyl)
		{ badsb(listerr, "NCYL LESS THAN NCG*CPG"); return (0); }
	if (sblock.fs_sbsize > SBSIZE)
		{ badsb(listerr, "SIZE PREPOSTEROUSLY LARGE"); return (0); }
	/*
	 * Set all possible fields that could differ, then do check
	 * of whole super block against an alternate super block.
	 * When an alternate super-block is specified this check is skipped.
	 */
	if (bflag)
		return (1);
	getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
	if (asblk.b_errs != NULL)
		return (0);
	altsblock.fs_link = sblock.fs_link;
	altsblock.fs_rlink = sblock.fs_rlink;
	altsblock.fs_time = sblock.fs_time;
	altsblock.fs_cstotal = sblock.fs_cstotal;
	altsblock.fs_cgrotor = sblock.fs_cgrotor;
	altsblock.fs_fmod = sblock.fs_fmod;
	altsblock.fs_clean = sblock.fs_clean;
	altsblock.fs_ronly = sblock.fs_ronly;
	altsblock.fs_flags = sblock.fs_flags;
	altsblock.fs_maxcontig = sblock.fs_maxcontig;
	altsblock.fs_minfree = sblock.fs_minfree;
	altsblock.fs_optim = sblock.fs_optim;
	altsblock.fs_rotdelay = sblock.fs_rotdelay;
	altsblock.fs_maxbpg = sblock.fs_maxbpg;
	bcopy((char *)sblock.fs_csp, (char *)altsblock.fs_csp,
		sizeof sblock.fs_csp);
	bcopy((char *)sblock.fs_fsmnt, (char *)altsblock.fs_fsmnt,
		sizeof sblock.fs_fsmnt);
	if (bcmp((char *)&sblock, (char *)&altsblock, (int)sblock.fs_sbsize))
		{ badsb(listerr, "TRASHED VALUES IN SUPER BLOCK"); return (0); }
	return (1);
#	undef altsblock
}

badsb(listerr, s)
	int listerr;
	char *s;
{

	if (!listerr)
		return;
	if (preen)
		printf("%s: ", devname);
	pfatal("BAD SUPER BLOCK: %s\n", s);
}

/*
 * Calculate a prototype superblock based on information in the disk label.
 * When done the cgsblock macro can be calculated and the fs_ncg field
 * can be used. Do NOT attempt to use other macros without verifying that
 * their needed information is available!
 */
calcsb(dev, devfd, fs)
	char *dev;
	int devfd;
	register struct fs *fs;
{
	register struct disklabel *lp;
	register struct partition *pp;
	register char *cp;
	struct disklabel *getdisklabel();
	int i;

	cp = index(dev, '\0') - 1;
	if (cp == (char *)-1 || (*cp < 'a' || *cp > 'h') && !isdigit(*cp)) {
		pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev);
		return (0);
	}
	lp = getdisklabel(dev, devfd);
	if (isdigit(*cp))
		pp = &lp->d_partitions[0];
	else
		pp = &lp->d_partitions[*cp - 'a'];
	if (pp->p_fstype != FS_BSDFFS) {
		pfatal("%s: NOT FORMATTED AS A BSD FILE SYSTEM (%s)\n",
			dev, pp->p_fstype < FSMAXTYPES ?
			fstypenames[pp->p_fstype] : "unknown");
		return (0);
	}
	bzero(fs, sizeof(struct fs));
	fs->fs_fsize = pp->p_fsize;
	fs->fs_frag = pp->p_frag;
	fs->fs_cpg = pp->p_cpg;
	fs->fs_size = pp->p_size;
	fs->fs_ntrak = lp->d_ntracks;
	fs->fs_nsect = lp->d_nsectors;
	fs->fs_spc = lp->d_secpercyl;
	fs->fs_nspf = fs->fs_fsize / lp->d_secsize;
	fs->fs_sblkno = roundup(
		howmany(lp->d_bbsize + lp->d_sbsize, fs->fs_fsize),
		fs->fs_frag);
	fs->fs_cgmask = 0xffffffff;
	for (i = fs->fs_ntrak; i > 1; i >>= 1)
		fs->fs_cgmask <<= 1;
	if (!POWEROF2(fs->fs_ntrak))
		fs->fs_cgmask <<= 1;
	fs->fs_cgoffset = roundup(
		howmany(fs->fs_nsect, NSPF(fs)), fs->fs_frag);
	fs->fs_fpg = (fs->fs_cpg * fs->fs_spc) / NSPF(fs);
	fs->fs_ncg = howmany(fs->fs_size / fs->fs_spc, fs->fs_cpg);
	for (fs->fs_fsbtodb = 0, i = NSPF(fs); i > 1; i >>= 1)
		fs->fs_fsbtodb++;
	return (1);
}

#ifdef byioctl
struct disklabel *
getdisklabel(s, fd)
	char *s;
	int	fd;
{
	static struct disklabel lab;

	if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) {
		perror("ioctl (GDINFO)");
		fatal("%s: can't read disk label", s);
	}
	return (&lab);
}
#else byioctl
char specname[64];
char boot[BBSIZE];

struct disklabel *
getdisklabel(s, fd)
	char *s;
	int	fd;
{
	char *cp;
	u_long magic = htonl(DISKMAGIC);
	register struct disklabel *lp;
	int cfd;

	/*
	 * Make name for 'c' partition.
	 */
	strcpy(specname, s);
	cp = specname + strlen(specname) - 1;
	if (!isdigit(*cp))
		*cp = 'c';
	cfd = open(specname, O_RDONLY);
	if (cfd < 0) {
		perror(specname);
		exit(2);
	}

	if (read(cfd, boot, BBSIZE) < BBSIZE) {
		perror(specname);
		exit(2);
	}
	close(cfd);
	for (lp = (struct disklabel *)(boot + LABELOFFSET);
	    lp <= (struct disklabel *)(boot + BBSIZE -
	    sizeof(struct disklabel));
	    lp = (struct disklabel *)((char *)lp + 128))
		if (lp->d_magic == magic && lp->d_magic2 == magic)
			break;
	if (lp > (struct disklabel *)(boot + BBSIZE -
	    sizeof(struct disklabel)) ||
	    lp->d_magic != magic || lp->d_magic2 != magic ||
	    dkcksum(lp) != 0) {
		printf("Bad pack magic number %s\n",
			"(label is damaged, or pack is unlabeled)");
		exit(1);
	}
#if ENDIAN != BIG
	swablabel(lp);
#endif
	return (lp);
}
#endif byioctl