xref: /csrg-svn/sbin/fsck/setup.c (revision 54207)
122054Sdist /*
239976Smckusick  * Copyright (c) 1980, 1986 The Regents of the University of California.
339976Smckusick  * All rights reserved.
439976Smckusick  *
542702Sbostic  * %sccs.include.redist.c%
622054Sdist  */
722054Sdist 
816268Smckusick #ifndef lint
9*54207Smckusick static char sccsid[] = "@(#)setup.c	5.39 (Berkeley) 06/22/92";
1039976Smckusick #endif /* not lint */
1116268Smckusick 
1230399Smckusick #define DKTYPENAMES
1316268Smckusick #include <sys/param.h>
1453703Smckusick #include <sys/time.h>
1551532Sbostic #include <ufs/ufs/dinode.h>
1651532Sbostic #include <ufs/ffs/fs.h>
1716268Smckusick #include <sys/stat.h>
1830399Smckusick #include <sys/ioctl.h>
1930399Smckusick #include <sys/disklabel.h>
2030399Smckusick #include <sys/file.h>
2144934Smckusick #include <errno.h>
2244934Smckusick #include <stdlib.h>
2344934Smckusick #include <string.h>
2430399Smckusick #include <ctype.h>
2516268Smckusick #include "fsck.h"
2616268Smckusick 
2739973Smckusick struct bufarea asblk;
2834225Smckusick #define altsblock (*asblk.b_un.b_fs)
2930399Smckusick #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
3030399Smckusick 
3138338Smckusick /*
3238338Smckusick  * The size of a cylinder group is calculated by CGSIZE. The maximum size
3338338Smckusick  * is limited by the fact that cylinder groups are at most one block.
3438338Smckusick  * Its size is derived from the size of the maps maintained in the
3538338Smckusick  * cylinder group and the (struct cg) size.
3638338Smckusick  */
3738338Smckusick #define CGSIZE(fs) \
3838338Smckusick     /* base cg */	(sizeof(struct cg) + \
3938338Smckusick     /* blktot size */	(fs)->fs_cpg * sizeof(long) + \
4038338Smckusick     /* blks size */	(fs)->fs_cpg * (fs)->fs_nrpos * sizeof(short) + \
4138338Smckusick     /* inode map */	howmany((fs)->fs_ipg, NBBY) + \
4238338Smckusick     /* block map */	howmany((fs)->fs_cpg * (fs)->fs_spc / NSPF(fs), NBBY))
4338338Smckusick 
4430399Smckusick char	*index();
4538376Smckusick struct	disklabel *getdisklabel();
4616268Smckusick 
4716268Smckusick setup(dev)
4816268Smckusick 	char *dev;
4916268Smckusick {
5039973Smckusick 	long cg, size, asked, i, j;
5139973Smckusick 	long bmapsize;
5238376Smckusick 	struct disklabel *lp;
53*54207Smckusick 	off_t sizepb;
5416268Smckusick 	struct stat statb;
5530399Smckusick 	struct fs proto;
5616268Smckusick 
5730859Skarels 	havesb = 0;
5816268Smckusick 	if (stat(dev, &statb) < 0) {
5944934Smckusick 		printf("Can't stat %s: %s\n", dev, strerror(errno));
6016268Smckusick 		return (0);
6116268Smckusick 	}
6241418Smckusick 	if ((statb.st_mode & S_IFMT) != S_IFCHR) {
6341418Smckusick 		pfatal("%s is not a character device", dev);
6441418Smckusick 		if (reply("CONTINUE") == 0)
6541418Smckusick 			return (0);
6641418Smckusick 	}
6739973Smckusick 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
6844934Smckusick 		printf("Can't open %s: %s\n", dev, strerror(errno));
6916268Smckusick 		return (0);
7016268Smckusick 	}
7116268Smckusick 	if (preen == 0)
7216268Smckusick 		printf("** %s", dev);
7339973Smckusick 	if (nflag || (fswritefd = open(dev, O_WRONLY)) < 0) {
7439973Smckusick 		fswritefd = -1;
7516268Smckusick 		if (preen)
7616268Smckusick 			pfatal("NO WRITE ACCESS");
7716268Smckusick 		printf(" (NO WRITE)");
7816268Smckusick 	}
7916268Smckusick 	if (preen == 0)
8016268Smckusick 		printf("\n");
8139973Smckusick 	fsmodified = 0;
8216268Smckusick 	lfdir = 0;
8316268Smckusick 	initbarea(&sblk);
8434140Smckusick 	initbarea(&asblk);
8538376Smckusick 	sblk.b_un.b_buf = malloc(SBSIZE);
8638376Smckusick 	asblk.b_un.b_buf = malloc(SBSIZE);
8738376Smckusick 	if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL)
8834225Smckusick 		errexit("cannot allocate space for superblock\n");
8939973Smckusick 	if (lp = getdisklabel((char *)NULL, fsreadfd))
9030859Skarels 		dev_bsize = secsize = lp->d_secsize;
9134140Smckusick 	else
9234140Smckusick 		dev_bsize = secsize = DEV_BSIZE;
9346563Smckusick #ifdef tahoe
9416268Smckusick 	/*
9546563Smckusick 	 * On the tahoe, the disk label and the disk driver disagree.
9646563Smckusick 	 * The label knows that sectors are 512 bytes, but the disk
9746563Smckusick 	 * drivers will only transfer in 1024 sized pieces.
9846563Smckusick 	 */
9946563Smckusick 	secsize = 1024;
10046563Smckusick #endif
10146563Smckusick 	/*
10230399Smckusick 	 * Read in the superblock, looking for alternates if necessary
10316268Smckusick 	 */
10430399Smckusick 	if (readsb(1) == 0) {
10539973Smckusick 		if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
10630399Smckusick 			return(0);
10730399Smckusick 		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
10830399Smckusick 			return (0);
10930399Smckusick 		for (cg = 0; cg < proto.fs_ncg; cg++) {
11030399Smckusick 			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
11130399Smckusick 			if (readsb(0) != 0)
11230399Smckusick 				break;
11330399Smckusick 		}
11430399Smckusick 		if (cg >= proto.fs_ncg) {
11530399Smckusick 			printf("%s %s\n%s %s\n%s %s\n",
11630399Smckusick 				"SEARCH FOR ALTERNATE SUPER-BLOCK",
11730399Smckusick 				"FAILED. YOU MUST USE THE",
11830399Smckusick 				"-b OPTION TO FSCK TO SPECIFY THE",
11930399Smckusick 				"LOCATION OF AN ALTERNATE",
12030399Smckusick 				"SUPER-BLOCK TO SUPPLY NEEDED",
12130399Smckusick 				"INFORMATION; SEE fsck(8).");
12230399Smckusick 			return(0);
12330399Smckusick 		}
12430399Smckusick 		pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag);
12530399Smckusick 	}
12639973Smckusick 	maxfsblock = sblock.fs_size;
12739973Smckusick 	maxino = sblock.fs_ncg * sblock.fs_ipg;
12816268Smckusick 	/*
12928213Smckusick 	 * Check and potentially fix certain fields in the super block.
13028213Smckusick 	 */
13128213Smckusick 	if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
13228213Smckusick 		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
13328213Smckusick 		if (reply("SET TO DEFAULT") == 1) {
13428213Smckusick 			sblock.fs_optim = FS_OPTTIME;
13528213Smckusick 			sbdirty();
13628213Smckusick 		}
13728213Smckusick 	}
13828213Smckusick 	if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
13928213Smckusick 		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
14028213Smckusick 			sblock.fs_minfree);
14128213Smckusick 		if (reply("SET TO DEFAULT") == 1) {
14228213Smckusick 			sblock.fs_minfree = 10;
14328213Smckusick 			sbdirty();
14428213Smckusick 		}
14528213Smckusick 	}
14644941Smckusick 	if (sblock.fs_interleave < 1 ||
14744941Smckusick 	    sblock.fs_interleave > sblock.fs_nsect) {
14830597Smckusick 		pwarn("IMPOSSIBLE INTERLEAVE=%d IN SUPERBLOCK",
14930400Smckusick 			sblock.fs_interleave);
15030586Smckusick 		sblock.fs_interleave = 1;
15130597Smckusick 		if (preen)
15230597Smckusick 			printf(" (FIXED)\n");
15334140Smckusick 		if (preen || reply("SET TO DEFAULT") == 1) {
15430400Smckusick 			sbdirty();
15534140Smckusick 			dirty(&asblk);
15634140Smckusick 		}
15730400Smckusick 	}
15844941Smckusick 	if (sblock.fs_npsect < sblock.fs_nsect ||
15944941Smckusick 	    sblock.fs_npsect > sblock.fs_nsect*2) {
16030597Smckusick 		pwarn("IMPOSSIBLE NPSECT=%d IN SUPERBLOCK",
16130400Smckusick 			sblock.fs_npsect);
16230586Smckusick 		sblock.fs_npsect = sblock.fs_nsect;
16330597Smckusick 		if (preen)
16430597Smckusick 			printf(" (FIXED)\n");
16534140Smckusick 		if (preen || reply("SET TO DEFAULT") == 1) {
16630400Smckusick 			sbdirty();
16734140Smckusick 			dirty(&asblk);
16834140Smckusick 		}
16930400Smckusick 	}
170*54207Smckusick 	if (sblock.fs_inodefmt < FS_44INODEFMT) {
171*54207Smckusick 		sizepb = sblock.fs_bsize;
172*54207Smckusick 		sblock.fs_maxfilesize = sblock.fs_bsize * NDADDR - 1;
173*54207Smckusick 		for (i = 0; i < NIADDR; i++) {
174*54207Smckusick 			sizepb *= NINDIR(&sblock);
175*54207Smckusick 			sblock.fs_maxfilesize += sizepb;
176*54207Smckusick 		}
177*54207Smckusick 		sblock.fs_qbmask = ~sblock.fs_bmask;
178*54207Smckusick 		sblock.fs_qfmask = ~sblock.fs_fmask;
179*54207Smckusick 	}
18034147Smckusick 	if (cvtflag) {
18134147Smckusick 		if (sblock.fs_postblformat == FS_42POSTBLFMT) {
18234147Smckusick 			/*
18334147Smckusick 			 * Requested to convert from old format to new format
18434147Smckusick 			 */
18534147Smckusick 			if (preen)
18634147Smckusick 				pwarn("CONVERTING TO NEW FILE SYSTEM FORMAT\n");
18734147Smckusick 			else if (!reply("CONVERT TO NEW FILE SYSTEM FORMAT"))
18834147Smckusick 				return(0);
18934140Smckusick 			sblock.fs_postblformat = FS_DYNAMICPOSTBLFMT;
19034140Smckusick 			sblock.fs_nrpos = 8;
19134140Smckusick 			sblock.fs_postbloff =
19234140Smckusick 			    (char *)(&sblock.fs_opostbl[0][0]) -
19334140Smckusick 			    (char *)(&sblock.fs_link);
19434140Smckusick 			sblock.fs_rotbloff = &sblock.fs_space[0] -
19534140Smckusick 			    (u_char *)(&sblock.fs_link);
19638338Smckusick 			sblock.fs_cgsize =
19738338Smckusick 				fragroundup(&sblock, CGSIZE(&sblock));
19834140Smckusick 			/*
19934140Smckusick 			 * Planning now for future expansion.
20034140Smckusick 			 */
20152013Smckusick #			ifdef _NOQUAD
20252013Smckusick 				sblock.fs_qbmask.val[_QUAD_HIGHWORD] = 0;
20352013Smckusick 				sblock.fs_qbmask.val[_QUAD_LOWWORD] =
20452013Smckusick 				    ~sblock.fs_bmask;
20552013Smckusick 				sblock.fs_qfmask.val[_QUAD_HIGHWORD] = 0;
20652013Smckusick 				sblock.fs_qfmask.val[_QUAD_LOWWORD] =
20752013Smckusick 				    ~sblock.fs_fmask;
20852013Smckusick #			else /* QUAD */
20952013Smckusick 				sblock.fs_qbmask = ~sblock.fs_bmask;
21052013Smckusick 				sblock.fs_qfmask = ~sblock.fs_fmask;
21152013Smckusick #			endif /* QUAD */
21234140Smckusick 			sbdirty();
21334140Smckusick 			dirty(&asblk);
21434147Smckusick 		} else if (sblock.fs_postblformat == FS_DYNAMICPOSTBLFMT) {
21534147Smckusick 			/*
21634147Smckusick 			 * Requested to convert from new format to old format
21734147Smckusick 			 */
21834147Smckusick 			if (sblock.fs_nrpos != 8 || sblock.fs_ipg > 2048 ||
21934147Smckusick 			    sblock.fs_cpg > 32 || sblock.fs_cpc > 16) {
22034147Smckusick 				printf(
22134147Smckusick 				"PARAMETERS OF CURRENT FILE SYSTEM DO NOT\n\t");
22234147Smckusick 				errexit(
22334147Smckusick 				"ALLOW CONVERSION TO OLD FILE SYSTEM FORMAT\n");
22434147Smckusick 			}
22534147Smckusick 			if (preen)
22634147Smckusick 				pwarn("CONVERTING TO OLD FILE SYSTEM FORMAT\n");
22734147Smckusick 			else if (!reply("CONVERT TO OLD FILE SYSTEM FORMAT"))
22834147Smckusick 				return(0);
22934147Smckusick 			sblock.fs_postblformat = FS_42POSTBLFMT;
23038338Smckusick 			sblock.fs_cgsize = fragroundup(&sblock,
23138338Smckusick 			    sizeof(struct ocg) + howmany(sblock.fs_fpg, NBBY));
23234147Smckusick 			sbdirty();
23334147Smckusick 			dirty(&asblk);
23434147Smckusick 		} else {
23534147Smckusick 			errexit("UNKNOWN FILE SYSTEM FORMAT\n");
23634140Smckusick 		}
23734140Smckusick 	}
23834140Smckusick 	if (asblk.b_dirty) {
23939973Smckusick 		bcopy((char *)&sblock, (char *)&altsblock,
24044934Smckusick 			(size_t)sblock.fs_sbsize);
24139973Smckusick 		flush(fswritefd, &asblk);
24234140Smckusick 	}
24328213Smckusick 	/*
24416268Smckusick 	 * read in the summary info.
24516268Smckusick 	 */
24633979Smckusick 	asked = 0;
24716268Smckusick 	for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
24816268Smckusick 		size = sblock.fs_cssize - i < sblock.fs_bsize ?
24916268Smckusick 		    sblock.fs_cssize - i : sblock.fs_bsize;
25016268Smckusick 		sblock.fs_csp[j] = (struct csum *)calloc(1, (unsigned)size);
25139973Smckusick 		if (bread(fsreadfd, (char *)sblock.fs_csp[j],
25216268Smckusick 		    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
25333979Smckusick 		    size) != 0 && !asked) {
25433979Smckusick 			pfatal("BAD SUMMARY INFORMATION");
25533979Smckusick 			if (reply("CONTINUE") == 0)
25633979Smckusick 				errexit("");
25733979Smckusick 			asked++;
25833979Smckusick 		}
25916268Smckusick 	}
26016268Smckusick 	/*
26116268Smckusick 	 * allocate and initialize the necessary maps
26216268Smckusick 	 */
26339973Smckusick 	bmapsize = roundup(howmany(maxfsblock, NBBY), sizeof(short));
26439973Smckusick 	blockmap = calloc((unsigned)bmapsize, sizeof (char));
26516268Smckusick 	if (blockmap == NULL) {
26644934Smckusick 		printf("cannot alloc %u bytes for blockmap\n",
26744934Smckusick 		    (unsigned)bmapsize);
26816268Smckusick 		goto badsb;
26916268Smckusick 	}
27039973Smckusick 	statemap = calloc((unsigned)(maxino + 1), sizeof(char));
27116268Smckusick 	if (statemap == NULL) {
27244934Smckusick 		printf("cannot alloc %u bytes for statemap\n",
27344934Smckusick 		    (unsigned)(maxino + 1));
27416268Smckusick 		goto badsb;
27516268Smckusick 	}
27639973Smckusick 	lncntp = (short *)calloc((unsigned)(maxino + 1), sizeof(short));
27716268Smckusick 	if (lncntp == NULL) {
27844934Smckusick 		printf("cannot alloc %u bytes for lncntp\n",
27944934Smckusick 		    (unsigned)(maxino + 1) * sizeof(short));
28016268Smckusick 		goto badsb;
28116268Smckusick 	}
28240020Smckusick 	numdirs = sblock.fs_cstotal.cs_ndir;
28340360Smckusick 	inplast = 0;
28440020Smckusick 	listmax = numdirs + 10;
28540020Smckusick 	inpsort = (struct inoinfo **)calloc((unsigned)listmax,
28640020Smckusick 	    sizeof(struct inoinfo *));
28740020Smckusick 	inphead = (struct inoinfo **)calloc((unsigned)numdirs,
28840020Smckusick 	    sizeof(struct inoinfo *));
28940020Smckusick 	if (inpsort == NULL || inphead == NULL) {
29044934Smckusick 		printf("cannot alloc %u bytes for inphead\n",
29144934Smckusick 		    (unsigned)numdirs * sizeof(struct inoinfo *));
29240020Smckusick 		goto badsb;
29340020Smckusick 	}
29434225Smckusick 	bufinit();
29516268Smckusick 	return (1);
29616268Smckusick 
29716268Smckusick badsb:
29816268Smckusick 	ckfini();
29916268Smckusick 	return (0);
30030399Smckusick }
30130399Smckusick 
30230399Smckusick /*
30330399Smckusick  * Read in the super block and its summary info.
30430399Smckusick  */
30530399Smckusick readsb(listerr)
30630399Smckusick 	int listerr;
30730399Smckusick {
30830859Skarels 	daddr_t super = bflag ? bflag : SBOFF / dev_bsize;
30930399Smckusick 
31039973Smckusick 	if (bread(fsreadfd, (char *)&sblock, super, (long)SBSIZE) != 0)
31130399Smckusick 		return (0);
31230399Smckusick 	sblk.b_bno = super;
31330399Smckusick 	sblk.b_size = SBSIZE;
31430399Smckusick 	/*
31530399Smckusick 	 * run a few consistency checks of the super block
31630399Smckusick 	 */
31730399Smckusick 	if (sblock.fs_magic != FS_MAGIC)
31830399Smckusick 		{ badsb(listerr, "MAGIC NUMBER WRONG"); return (0); }
31930399Smckusick 	if (sblock.fs_ncg < 1)
32030399Smckusick 		{ badsb(listerr, "NCG OUT OF RANGE"); return (0); }
32134140Smckusick 	if (sblock.fs_cpg < 1)
32230399Smckusick 		{ badsb(listerr, "CPG OUT OF RANGE"); return (0); }
32330399Smckusick 	if (sblock.fs_ncg * sblock.fs_cpg < sblock.fs_ncyl ||
32430399Smckusick 	    (sblock.fs_ncg - 1) * sblock.fs_cpg >= sblock.fs_ncyl)
32530399Smckusick 		{ badsb(listerr, "NCYL LESS THAN NCG*CPG"); return (0); }
32630399Smckusick 	if (sblock.fs_sbsize > SBSIZE)
32730399Smckusick 		{ badsb(listerr, "SIZE PREPOSTEROUSLY LARGE"); return (0); }
32830399Smckusick 	/*
32930859Skarels 	 * Compute block size that the filesystem is based on,
33030859Skarels 	 * according to fsbtodb, and adjust superblock block number
33130859Skarels 	 * so we can tell if this is an alternate later.
33230859Skarels 	 */
33330859Skarels 	super *= dev_bsize;
33430859Skarels 	dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
33530859Skarels 	sblk.b_bno = super / dev_bsize;
33653613Smckusick 	if (bflag) {
33753613Smckusick 		havesb = 1;
33853613Smckusick 		return (1);
33953613Smckusick 	}
34030859Skarels 	/*
34130399Smckusick 	 * Set all possible fields that could differ, then do check
34230399Smckusick 	 * of whole super block against an alternate super block.
34330399Smckusick 	 * When an alternate super-block is specified this check is skipped.
34430399Smckusick 	 */
34534140Smckusick 	getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
34638376Smckusick 	if (asblk.b_errs)
34734140Smckusick 		return (0);
34830399Smckusick 	altsblock.fs_link = sblock.fs_link;
34930399Smckusick 	altsblock.fs_rlink = sblock.fs_rlink;
35030399Smckusick 	altsblock.fs_time = sblock.fs_time;
35130399Smckusick 	altsblock.fs_cstotal = sblock.fs_cstotal;
35230399Smckusick 	altsblock.fs_cgrotor = sblock.fs_cgrotor;
35330399Smckusick 	altsblock.fs_fmod = sblock.fs_fmod;
35430399Smckusick 	altsblock.fs_clean = sblock.fs_clean;
35530399Smckusick 	altsblock.fs_ronly = sblock.fs_ronly;
35630399Smckusick 	altsblock.fs_flags = sblock.fs_flags;
35730399Smckusick 	altsblock.fs_maxcontig = sblock.fs_maxcontig;
35830399Smckusick 	altsblock.fs_minfree = sblock.fs_minfree;
35930399Smckusick 	altsblock.fs_optim = sblock.fs_optim;
36030399Smckusick 	altsblock.fs_rotdelay = sblock.fs_rotdelay;
36130399Smckusick 	altsblock.fs_maxbpg = sblock.fs_maxbpg;
36230399Smckusick 	bcopy((char *)sblock.fs_csp, (char *)altsblock.fs_csp,
36330399Smckusick 		sizeof sblock.fs_csp);
36430399Smckusick 	bcopy((char *)sblock.fs_fsmnt, (char *)altsblock.fs_fsmnt,
36530399Smckusick 		sizeof sblock.fs_fsmnt);
36630565Skarels 	bcopy((char *)sblock.fs_sparecon, (char *)altsblock.fs_sparecon,
36730565Skarels 		sizeof sblock.fs_sparecon);
36834140Smckusick 	/*
36934140Smckusick 	 * The following should not have to be copied.
37034140Smckusick 	 */
37134140Smckusick 	altsblock.fs_fsbtodb = sblock.fs_fsbtodb;
37234140Smckusick 	altsblock.fs_interleave = sblock.fs_interleave;
37334140Smckusick 	altsblock.fs_npsect = sblock.fs_npsect;
37434140Smckusick 	altsblock.fs_nrpos = sblock.fs_nrpos;
37554023Smckusick 	altsblock.fs_qbmask = sblock.fs_qbmask;
37654023Smckusick 	altsblock.fs_qfmask = sblock.fs_qfmask;
37754023Smckusick 	altsblock.fs_state = sblock.fs_state;
37854023Smckusick 	altsblock.fs_maxfilesize = sblock.fs_maxfilesize;
37930565Skarels 	if (bcmp((char *)&sblock, (char *)&altsblock, (int)sblock.fs_sbsize)) {
38030565Skarels 		badsb(listerr,
38130565Skarels 		"VALUES IN SUPER BLOCK DISAGREE WITH THOSE IN FIRST ALTERNATE");
38230565Skarels 		return (0);
38330565Skarels 	}
38430859Skarels 	havesb = 1;
38530399Smckusick 	return (1);
38616268Smckusick }
38716268Smckusick 
38830399Smckusick badsb(listerr, s)
38930399Smckusick 	int listerr;
39016268Smckusick 	char *s;
39116268Smckusick {
39216268Smckusick 
39330399Smckusick 	if (!listerr)
39430399Smckusick 		return;
39516268Smckusick 	if (preen)
39616268Smckusick 		printf("%s: ", devname);
39730399Smckusick 	pfatal("BAD SUPER BLOCK: %s\n", s);
39816268Smckusick }
39930399Smckusick 
40030399Smckusick /*
40130399Smckusick  * Calculate a prototype superblock based on information in the disk label.
40230399Smckusick  * When done the cgsblock macro can be calculated and the fs_ncg field
40330399Smckusick  * can be used. Do NOT attempt to use other macros without verifying that
40430399Smckusick  * their needed information is available!
40530399Smckusick  */
40630399Smckusick calcsb(dev, devfd, fs)
40730399Smckusick 	char *dev;
40830399Smckusick 	int devfd;
40930399Smckusick 	register struct fs *fs;
41030399Smckusick {
41130399Smckusick 	register struct disklabel *lp;
41230399Smckusick 	register struct partition *pp;
41330399Smckusick 	register char *cp;
41430399Smckusick 	int i;
41530399Smckusick 
41630399Smckusick 	cp = index(dev, '\0') - 1;
41730399Smckusick 	if (cp == (char *)-1 || (*cp < 'a' || *cp > 'h') && !isdigit(*cp)) {
41830399Smckusick 		pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev);
41930399Smckusick 		return (0);
42030399Smckusick 	}
42130399Smckusick 	lp = getdisklabel(dev, devfd);
42230399Smckusick 	if (isdigit(*cp))
42330399Smckusick 		pp = &lp->d_partitions[0];
42430399Smckusick 	else
42530399Smckusick 		pp = &lp->d_partitions[*cp - 'a'];
42630399Smckusick 	if (pp->p_fstype != FS_BSDFFS) {
42730859Skarels 		pfatal("%s: NOT LABELED AS A BSD FILE SYSTEM (%s)\n",
42830399Smckusick 			dev, pp->p_fstype < FSMAXTYPES ?
42930399Smckusick 			fstypenames[pp->p_fstype] : "unknown");
43030399Smckusick 		return (0);
43130399Smckusick 	}
43239973Smckusick 	bzero((char *)fs, sizeof(struct fs));
43330399Smckusick 	fs->fs_fsize = pp->p_fsize;
43430399Smckusick 	fs->fs_frag = pp->p_frag;
43530399Smckusick 	fs->fs_cpg = pp->p_cpg;
43630399Smckusick 	fs->fs_size = pp->p_size;
43730399Smckusick 	fs->fs_ntrak = lp->d_ntracks;
43830399Smckusick 	fs->fs_nsect = lp->d_nsectors;
43930399Smckusick 	fs->fs_spc = lp->d_secpercyl;
44030399Smckusick 	fs->fs_nspf = fs->fs_fsize / lp->d_secsize;
44130399Smckusick 	fs->fs_sblkno = roundup(
44230399Smckusick 		howmany(lp->d_bbsize + lp->d_sbsize, fs->fs_fsize),
44330399Smckusick 		fs->fs_frag);
44430399Smckusick 	fs->fs_cgmask = 0xffffffff;
44530399Smckusick 	for (i = fs->fs_ntrak; i > 1; i >>= 1)
44630399Smckusick 		fs->fs_cgmask <<= 1;
44730399Smckusick 	if (!POWEROF2(fs->fs_ntrak))
44830399Smckusick 		fs->fs_cgmask <<= 1;
44930399Smckusick 	fs->fs_cgoffset = roundup(
45030399Smckusick 		howmany(fs->fs_nsect, NSPF(fs)), fs->fs_frag);
45130399Smckusick 	fs->fs_fpg = (fs->fs_cpg * fs->fs_spc) / NSPF(fs);
45230399Smckusick 	fs->fs_ncg = howmany(fs->fs_size / fs->fs_spc, fs->fs_cpg);
45330399Smckusick 	for (fs->fs_fsbtodb = 0, i = NSPF(fs); i > 1; i >>= 1)
45430399Smckusick 		fs->fs_fsbtodb++;
45530859Skarels 	dev_bsize = lp->d_secsize;
45630399Smckusick 	return (1);
45730399Smckusick }
45830399Smckusick 
45930399Smckusick struct disklabel *
46030399Smckusick getdisklabel(s, fd)
46130399Smckusick 	char *s;
46230399Smckusick 	int	fd;
46330399Smckusick {
46430399Smckusick 	static struct disklabel lab;
46530399Smckusick 
46630399Smckusick 	if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) {
46730609Skarels 		if (s == NULL)
46830609Skarels 			return ((struct disklabel *)NULL);
46944934Smckusick 		pwarn("ioctl (GCINFO): %s\n", strerror(errno));
47044305Smckusick 		errexit("%s: can't read disk label\n", s);
47130399Smckusick 	}
47230399Smckusick 	return (&lab);
47330399Smckusick }
474