xref: /csrg-svn/sbin/fsck/setup.c (revision 30399)
1 /*
2  * Copyright (c) 1980 Regents of the University of California.
3  * All rights reserved.  The Berkeley software License Agreement
4  * specifies the terms and conditions for redistribution.
5  */
6 
7 #ifndef lint
8 static char sccsid[] = "@(#)setup.c	5.4 (Berkeley) 01/15/87";
9 #endif not lint
10 
11 #define DKTYPENAMES
12 #include <sys/param.h>
13 #include <sys/inode.h>
14 #include <sys/fs.h>
15 #include <sys/stat.h>
16 #include <sys/ioctl.h>
17 #include <sys/disklabel.h>
18 #include <sys/file.h>
19 #include <ctype.h>
20 #include "fsck.h"
21 
22 #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
23 
24 char	*calloc();
25 char	*index();
26 
27 setup(dev)
28 	char *dev;
29 {
30 	dev_t rootdev;
31 	long cg, ncg, size, i, j;
32 	struct stat statb;
33 	struct fs proto;
34 
35 	if (stat("/", &statb) < 0)
36 		errexit("Can't stat root\n");
37 	rootdev = statb.st_dev;
38 	if (stat(dev, &statb) < 0) {
39 		printf("Can't stat %s\n", dev);
40 		return (0);
41 	}
42 	rawflg = 0;
43 	if ((statb.st_mode & S_IFMT) == S_IFBLK)
44 		;
45 	else if ((statb.st_mode & S_IFMT) == S_IFCHR)
46 		rawflg++;
47 	else {
48 		if (reply("file is not a block or character device; OK") == 0)
49 			return (0);
50 	}
51 	if (rootdev == statb.st_rdev)
52 		hotroot++;
53 	if ((dfile.rfdes = open(dev, O_RDONLY)) < 0) {
54 		printf("Can't open %s\n", dev);
55 		return (0);
56 	}
57 	if (preen == 0)
58 		printf("** %s", dev);
59 	if (nflag || (dfile.wfdes = open(dev, O_WRONLY)) < 0) {
60 		dfile.wfdes = -1;
61 		if (preen)
62 			pfatal("NO WRITE ACCESS");
63 		printf(" (NO WRITE)");
64 	}
65 	if (preen == 0)
66 		printf("\n");
67 	dfile.mod = 0;
68 	lfdir = 0;
69 	initbarea(&sblk);
70 	initbarea(&fileblk);
71 	initbarea(&inoblk);
72 	initbarea(&cgblk);
73 	/*
74 	 * Read in the superblock, looking for alternates if necessary
75 	 */
76 	if (readsb(1) == 0) {
77 		if (bflag || calcsb(dev, dfile.rfdes, &proto) == 0 || preen)
78 			return(0);
79 		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
80 			return (0);
81 		for (cg = 0; cg < proto.fs_ncg; cg++) {
82 			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
83 			if (readsb(0) != 0)
84 				break;
85 		}
86 		if (cg >= proto.fs_ncg) {
87 			printf("%s %s\n%s %s\n%s %s\n",
88 				"SEARCH FOR ALTERNATE SUPER-BLOCK",
89 				"FAILED. YOU MUST USE THE",
90 				"-b OPTION TO FSCK TO SPECIFY THE",
91 				"LOCATION OF AN ALTERNATE",
92 				"SUPER-BLOCK TO SUPPLY NEEDED",
93 				"INFORMATION; SEE fsck(8).");
94 			return(0);
95 		}
96 		pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag);
97 	}
98 	fmax = sblock.fs_size;
99 	imax = sblock.fs_ncg * sblock.fs_ipg;
100 	/*
101 	 * Check and potentially fix certain fields in the super block.
102 	 */
103 	if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
104 		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
105 		if (reply("SET TO DEFAULT") == 1) {
106 			sblock.fs_optim = FS_OPTTIME;
107 			sbdirty();
108 		}
109 	}
110 	if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
111 		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
112 			sblock.fs_minfree);
113 		if (reply("SET TO DEFAULT") == 1) {
114 			sblock.fs_minfree = 10;
115 			sbdirty();
116 		}
117 	}
118 	/*
119 	 * read in the summary info.
120 	 */
121 	for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
122 		size = sblock.fs_cssize - i < sblock.fs_bsize ?
123 		    sblock.fs_cssize - i : sblock.fs_bsize;
124 		sblock.fs_csp[j] = (struct csum *)calloc(1, (unsigned)size);
125 		if (bread(&dfile, (char *)sblock.fs_csp[j],
126 		    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
127 		    size) != 0)
128 			return (0);
129 	}
130 	/*
131 	 * allocate and initialize the necessary maps
132 	 */
133 	bmapsz = roundup(howmany(fmax, NBBY), sizeof(short));
134 	blockmap = calloc((unsigned)bmapsz, sizeof (char));
135 	if (blockmap == NULL) {
136 		printf("cannot alloc %d bytes for blockmap\n", bmapsz);
137 		goto badsb;
138 	}
139 	statemap = calloc((unsigned)(imax + 1), sizeof(char));
140 	if (statemap == NULL) {
141 		printf("cannot alloc %d bytes for statemap\n", imax + 1);
142 		goto badsb;
143 	}
144 	lncntp = (short *)calloc((unsigned)(imax + 1), sizeof(short));
145 	if (lncntp == NULL) {
146 		printf("cannot alloc %d bytes for lncntp\n",
147 		    (imax + 1) * sizeof(short));
148 		goto badsb;
149 	}
150 
151 	return (1);
152 
153 badsb:
154 	ckfini();
155 	return (0);
156 }
157 
158 /*
159  * Read in the super block and its summary info.
160  */
161 readsb(listerr)
162 	int listerr;
163 {
164 	BUFAREA asblk;
165 #	define altsblock asblk.b_un.b_fs
166 	daddr_t super = bflag ? bflag : SBLOCK;
167 
168 	initbarea(&asblk);
169 	if (bread(&dfile, (char *)&sblock, super, (long)SBSIZE) != 0)
170 		return (0);
171 	sblk.b_bno = super;
172 	sblk.b_size = SBSIZE;
173 	/*
174 	 * run a few consistency checks of the super block
175 	 */
176 	if (sblock.fs_magic != FS_MAGIC)
177 		{ badsb(listerr, "MAGIC NUMBER WRONG"); return (0); }
178 	if (sblock.fs_ncg < 1)
179 		{ badsb(listerr, "NCG OUT OF RANGE"); return (0); }
180 	if (sblock.fs_cpg < 1 || sblock.fs_cpg > MAXCPG)
181 		{ badsb(listerr, "CPG OUT OF RANGE"); return (0); }
182 	if (sblock.fs_ncg * sblock.fs_cpg < sblock.fs_ncyl ||
183 	    (sblock.fs_ncg - 1) * sblock.fs_cpg >= sblock.fs_ncyl)
184 		{ badsb(listerr, "NCYL LESS THAN NCG*CPG"); return (0); }
185 	if (sblock.fs_sbsize > SBSIZE)
186 		{ badsb(listerr, "SIZE PREPOSTEROUSLY LARGE"); return (0); }
187 	/*
188 	 * Set all possible fields that could differ, then do check
189 	 * of whole super block against an alternate super block.
190 	 * When an alternate super-block is specified this check is skipped.
191 	 */
192 	if (bflag)
193 		return (1);
194 	getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
195 	if (asblk.b_errs != NULL)
196 		return (0);
197 	altsblock.fs_link = sblock.fs_link;
198 	altsblock.fs_rlink = sblock.fs_rlink;
199 	altsblock.fs_time = sblock.fs_time;
200 	altsblock.fs_cstotal = sblock.fs_cstotal;
201 	altsblock.fs_cgrotor = sblock.fs_cgrotor;
202 	altsblock.fs_fmod = sblock.fs_fmod;
203 	altsblock.fs_clean = sblock.fs_clean;
204 	altsblock.fs_ronly = sblock.fs_ronly;
205 	altsblock.fs_flags = sblock.fs_flags;
206 	altsblock.fs_maxcontig = sblock.fs_maxcontig;
207 	altsblock.fs_minfree = sblock.fs_minfree;
208 	altsblock.fs_optim = sblock.fs_optim;
209 	altsblock.fs_rotdelay = sblock.fs_rotdelay;
210 	altsblock.fs_maxbpg = sblock.fs_maxbpg;
211 	bcopy((char *)sblock.fs_csp, (char *)altsblock.fs_csp,
212 		sizeof sblock.fs_csp);
213 	bcopy((char *)sblock.fs_fsmnt, (char *)altsblock.fs_fsmnt,
214 		sizeof sblock.fs_fsmnt);
215 	if (bcmp((char *)&sblock, (char *)&altsblock, (int)sblock.fs_sbsize))
216 		{ badsb(listerr, "TRASHED VALUES IN SUPER BLOCK"); return (0); }
217 	return (1);
218 #	undef altsblock
219 }
220 
221 badsb(listerr, s)
222 	int listerr;
223 	char *s;
224 {
225 
226 	if (!listerr)
227 		return;
228 	if (preen)
229 		printf("%s: ", devname);
230 	pfatal("BAD SUPER BLOCK: %s\n", s);
231 }
232 
233 /*
234  * Calculate a prototype superblock based on information in the disk label.
235  * When done the cgsblock macro can be calculated and the fs_ncg field
236  * can be used. Do NOT attempt to use other macros without verifying that
237  * their needed information is available!
238  */
239 calcsb(dev, devfd, fs)
240 	char *dev;
241 	int devfd;
242 	register struct fs *fs;
243 {
244 	register struct disklabel *lp;
245 	register struct partition *pp;
246 	register char *cp;
247 	struct disklabel *getdisklabel();
248 	int i;
249 
250 	cp = index(dev, '\0') - 1;
251 	if (cp == (char *)-1 || (*cp < 'a' || *cp > 'h') && !isdigit(*cp)) {
252 		pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev);
253 		return (0);
254 	}
255 	lp = getdisklabel(dev, devfd);
256 	if (isdigit(*cp))
257 		pp = &lp->d_partitions[0];
258 	else
259 		pp = &lp->d_partitions[*cp - 'a'];
260 	if (pp->p_fstype != FS_BSDFFS) {
261 		pfatal("%s: NOT FORMATTED AS A BSD FILE SYSTEM (%s)\n",
262 			dev, pp->p_fstype < FSMAXTYPES ?
263 			fstypenames[pp->p_fstype] : "unknown");
264 		return (0);
265 	}
266 	bzero(fs, sizeof(struct fs));
267 	fs->fs_fsize = pp->p_fsize;
268 	fs->fs_frag = pp->p_frag;
269 	fs->fs_cpg = pp->p_cpg;
270 	fs->fs_size = pp->p_size;
271 	fs->fs_ntrak = lp->d_ntracks;
272 	fs->fs_nsect = lp->d_nsectors;
273 	fs->fs_spc = lp->d_secpercyl;
274 	fs->fs_nspf = fs->fs_fsize / lp->d_secsize;
275 	fs->fs_sblkno = roundup(
276 		howmany(lp->d_bbsize + lp->d_sbsize, fs->fs_fsize),
277 		fs->fs_frag);
278 	fs->fs_cgmask = 0xffffffff;
279 	for (i = fs->fs_ntrak; i > 1; i >>= 1)
280 		fs->fs_cgmask <<= 1;
281 	if (!POWEROF2(fs->fs_ntrak))
282 		fs->fs_cgmask <<= 1;
283 	fs->fs_cgoffset = roundup(
284 		howmany(fs->fs_nsect, NSPF(fs)), fs->fs_frag);
285 	fs->fs_fpg = (fs->fs_cpg * fs->fs_spc) / NSPF(fs);
286 	fs->fs_ncg = howmany(fs->fs_size / fs->fs_spc, fs->fs_cpg);
287 	for (fs->fs_fsbtodb = 0, i = NSPF(fs); i > 1; i >>= 1)
288 		fs->fs_fsbtodb++;
289 	return (1);
290 }
291 
292 #ifdef byioctl
293 struct disklabel *
294 getdisklabel(s, fd)
295 	char *s;
296 	int	fd;
297 {
298 	static struct disklabel lab;
299 
300 	if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) {
301 		perror("ioctl (GDINFO)");
302 		fatal("%s: can't read disk label", s);
303 	}
304 	return (&lab);
305 }
306 #else byioctl
307 char specname[64];
308 char boot[BBSIZE];
309 
310 struct disklabel *
311 getdisklabel(s, fd)
312 	char *s;
313 	int	fd;
314 {
315 	char *cp;
316 	u_long magic = htonl(DISKMAGIC);
317 	register struct disklabel *lp;
318 	int cfd;
319 
320 	/*
321 	 * Make name for 'c' partition.
322 	 */
323 	strcpy(specname, s);
324 	cp = specname + strlen(specname) - 1;
325 	if (!isdigit(*cp))
326 		*cp = 'c';
327 	cfd = open(specname, O_RDONLY);
328 	if (cfd < 0) {
329 		perror(specname);
330 		exit(2);
331 	}
332 
333 	if (read(cfd, boot, BBSIZE) < BBSIZE) {
334 		perror(specname);
335 		exit(2);
336 	}
337 	close(cfd);
338 	for (lp = (struct disklabel *)(boot + LABELOFFSET);
339 	    lp <= (struct disklabel *)(boot + BBSIZE -
340 	    sizeof(struct disklabel));
341 	    lp = (struct disklabel *)((char *)lp + 128))
342 		if (lp->d_magic == magic && lp->d_magic2 == magic)
343 			break;
344 	if (lp > (struct disklabel *)(boot + BBSIZE -
345 	    sizeof(struct disklabel)) ||
346 	    lp->d_magic != magic || lp->d_magic2 != magic ||
347 	    dkcksum(lp) != 0) {
348 		printf("Bad pack magic number %s\n",
349 			"(label is damaged, or pack is unlabeled)");
350 		exit(1);
351 	}
352 #if ENDIAN != BIG
353 	swablabel(lp);
354 #endif
355 	return (lp);
356 }
357 #endif byioctl
358