xref: /freebsd/sbin/quotacheck/quotacheck.c (revision 6af83ee0d2941d18880b6aaa2b4facd1d30c6106)
1 /*
2  * Copyright (c) 1980, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Robert Elz at The University of Melbourne.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #if 0
34 #ifndef lint
35 static const char copyright[] =
36 "@(#) Copyright (c) 1980, 1990, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 static char sccsid[] = "@(#)quotacheck.c	8.3 (Berkeley) 1/29/94";
42 #endif /* not lint */
43 #endif
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 /*
48  * Fix up / report on disk quotas & usage
49  */
50 #include <sys/param.h>
51 #include <sys/disklabel.h>
52 #include <sys/stat.h>
53 
54 #include <ufs/ufs/dinode.h>
55 #include <ufs/ufs/quota.h>
56 #include <ufs/ffs/fs.h>
57 
58 #include <err.h>
59 #include <errno.h>
60 #include <fcntl.h>
61 #include <fstab.h>
62 #include <grp.h>
63 #include <pwd.h>
64 #include <stdio.h>
65 #include <stdlib.h>
66 #include <string.h>
67 #include <unistd.h>
68 
69 char *qfname = QUOTAFILENAME;
70 char *qfextension[] = INITQFNAMES;
71 char *quotagroup = QUOTAGROUP;
72 
73 union {
74 	struct	fs	sblk;
75 	char	dummy[MAXBSIZE];
76 } sb_un;
77 #define	sblock	sb_un.sblk
78 union {
79 	struct	cg	cgblk;
80 	char	dummy[MAXBSIZE];
81 } cg_un;
82 #define	cgblk	cg_un.cgblk
83 long dev_bsize = 1;
84 ino_t maxino;
85 
86 union dinode {
87 	struct ufs1_dinode dp1;
88 	struct ufs2_dinode dp2;
89 };
90 #define	DIP(dp, field) \
91 	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
92 	(dp)->dp1.field : (dp)->dp2.field)
93 
94 struct quotaname {
95 	long	flags;
96 	char	grpqfname[PATH_MAX];
97 	char	usrqfname[PATH_MAX];
98 };
99 #define	HASUSR	1
100 #define	HASGRP	2
101 
102 struct fileusage {
103 	struct	fileusage *fu_next;
104 	u_long	fu_curinodes;
105 	u_long	fu_curblocks;
106 	u_long	fu_id;
107 	char	fu_name[1];
108 	/* actually bigger */
109 };
110 #define FUHASH 1024	/* must be power of two */
111 struct fileusage *fuhead[MAXQUOTAS][FUHASH];
112 
113 int	aflag;			/* all file systems */
114 int	gflag;			/* check group quotas */
115 int	uflag;			/* check user quotas */
116 int	vflag;			/* verbose */
117 int	fi;			/* open disk file descriptor */
118 u_long	highid[MAXQUOTAS];	/* highest addid()'ed identifier per type */
119 
120 struct fileusage *
121 	 addid(u_long, int, char *);
122 char	*blockcheck(char *);
123 void	 bread(ufs2_daddr_t, char *, long);
124 extern int checkfstab(int, int, void * (*)(struct fstab *),
125 				int (*)(char *, char *, struct quotaname *));
126 int	 chkquota(char *, char *, struct quotaname *);
127 void	 freeinodebuf(void);
128 union dinode *
129 	 getnextinode(ino_t);
130 int	 getquotagid(void);
131 int	 hasquota(struct fstab *, int, char **);
132 struct fileusage *
133 	 lookup(u_long, int);
134 void	*needchk(struct fstab *);
135 int	 oneof(char *, char*[], int);
136 void	 setinodebuf(ino_t);
137 int	 update(char *, char *, int);
138 void	 usage(void);
139 
140 int
141 main(argc, argv)
142 	int argc;
143 	char *argv[];
144 {
145 	struct fstab *fs;
146 	struct passwd *pw;
147 	struct group *gr;
148 	struct quotaname *auxdata;
149 	int i, argnum, maxrun, errs, ch;
150 	long done = 0;
151 	char *name;
152 
153 	errs = maxrun = 0;
154 	while ((ch = getopt(argc, argv, "aguvl:")) != -1) {
155 		switch(ch) {
156 		case 'a':
157 			aflag++;
158 			break;
159 		case 'g':
160 			gflag++;
161 			break;
162 		case 'u':
163 			uflag++;
164 			break;
165 		case 'v':
166 			vflag++;
167 			break;
168 		case 'l':
169 			maxrun = atoi(optarg);
170 			break;
171 		default:
172 			usage();
173 		}
174 	}
175 	argc -= optind;
176 	argv += optind;
177 	if ((argc == 0 && !aflag) || (argc > 0 && aflag))
178 		usage();
179 	if (!gflag && !uflag) {
180 		gflag++;
181 		uflag++;
182 	}
183 	if (gflag) {
184 		setgrent();
185 		while ((gr = getgrent()) != NULL)
186 			(void) addid((u_long)gr->gr_gid, GRPQUOTA, gr->gr_name);
187 		endgrent();
188 	}
189 	if (uflag) {
190 		setpwent();
191 		while ((pw = getpwent()) != NULL)
192 			(void) addid((u_long)pw->pw_uid, USRQUOTA, pw->pw_name);
193 		endpwent();
194 	}
195 	if (aflag)
196 		exit(checkfstab(1, maxrun, needchk, chkquota));
197 	if (setfsent() == 0)
198 		errx(1, "%s: can't open", FSTAB);
199 	while ((fs = getfsent()) != NULL) {
200 		if (((argnum = oneof(fs->fs_file, argv, argc)) >= 0 ||
201 		    (argnum = oneof(fs->fs_spec, argv, argc)) >= 0) &&
202 		    (auxdata = needchk(fs)) &&
203 		    (name = blockcheck(fs->fs_spec))) {
204 			done |= 1 << argnum;
205 			errs += chkquota(name, fs->fs_file, auxdata);
206 		}
207 	}
208 	endfsent();
209 	for (i = 0; i < argc; i++)
210 		if ((done & (1 << i)) == 0)
211 			fprintf(stderr, "%s not found in %s\n",
212 				argv[i], FSTAB);
213 	exit(errs);
214 }
215 
216 void
217 usage()
218 {
219 	(void)fprintf(stderr, "%s\n%s\n",
220 		"usage: quotacheck [-guv] -a",
221 		"       quotacheck [-guv] filesystem ...");
222 	exit(1);
223 }
224 
225 void *
226 needchk(fs)
227 	struct fstab *fs;
228 {
229 	struct quotaname *qnp;
230 	char *qfnp;
231 
232 	if (strcmp(fs->fs_vfstype, "ufs") ||
233 	    strcmp(fs->fs_type, FSTAB_RW))
234 		return (NULL);
235 	if ((qnp = malloc(sizeof(*qnp))) == NULL)
236 		errx(1, "malloc failed");
237 	qnp->flags = 0;
238 	if (gflag && hasquota(fs, GRPQUOTA, &qfnp)) {
239 		strcpy(qnp->grpqfname, qfnp);
240 		qnp->flags |= HASGRP;
241 	}
242 	if (uflag && hasquota(fs, USRQUOTA, &qfnp)) {
243 		strcpy(qnp->usrqfname, qfnp);
244 		qnp->flags |= HASUSR;
245 	}
246 	if (qnp->flags)
247 		return (qnp);
248 	free(qnp);
249 	return (NULL);
250 }
251 
252 /*
253  * Possible superblock locations ordered from most to least likely.
254  */
255 static int sblock_try[] = SBLOCKSEARCH;
256 
257 /*
258  * Scan the specified file system to check quota(s) present on it.
259  */
260 int
261 chkquota(fsname, mntpt, qnp)
262 	char *fsname, *mntpt;
263 	struct quotaname *qnp;
264 {
265 	struct fileusage *fup;
266 	union dinode *dp;
267 	int cg, i, mode, errs = 0;
268 	ino_t ino, inosused;
269 	char *cp;
270 
271 	if ((fi = open(fsname, O_RDONLY, 0)) < 0) {
272 		warn("%s", fsname);
273 		return (1);
274 	}
275 	if (vflag) {
276 		(void)printf("*** Checking ");
277 		if (qnp->flags & HASUSR)
278 			(void)printf("%s%s", qfextension[USRQUOTA],
279 			    (qnp->flags & HASGRP) ? " and " : "");
280 		if (qnp->flags & HASGRP)
281 			(void)printf("%s", qfextension[GRPQUOTA]);
282 		(void)printf(" quotas for %s (%s)\n", fsname, mntpt);
283 	}
284 	sync();
285 	dev_bsize = 1;
286 	for (i = 0; sblock_try[i] != -1; i++) {
287 		bread(sblock_try[i], (char *)&sblock, (long)SBLOCKSIZE);
288 		if ((sblock.fs_magic == FS_UFS1_MAGIC ||
289 		     (sblock.fs_magic == FS_UFS2_MAGIC &&
290 		      sblock.fs_sblockloc == sblock_try[i])) &&
291 		    sblock.fs_bsize <= MAXBSIZE &&
292 		    sblock.fs_bsize >= sizeof(struct fs))
293 			break;
294 	}
295 	if (sblock_try[i] == -1) {
296 		warn("Cannot find file system superblock");
297 		return (1);
298 	}
299 	dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
300 	maxino = sblock.fs_ncg * sblock.fs_ipg;
301 	for (cg = 0; cg < sblock.fs_ncg; cg++) {
302 		ino = cg * sblock.fs_ipg;
303 		setinodebuf(ino);
304 		bread(fsbtodb(&sblock, cgtod(&sblock, cg)), (char *)(&cgblk),
305 		    sblock.fs_cgsize);
306 		if (sblock.fs_magic == FS_UFS2_MAGIC)
307 			inosused = cgblk.cg_initediblk;
308 		else
309 			inosused = sblock.fs_ipg;
310 		/*
311 		 * If we are using soft updates, then we can trust the
312 		 * cylinder group inode allocation maps to tell us which
313 		 * inodes are allocated. We will scan the used inode map
314 		 * to find the inodes that are really in use, and then
315 		 * read only those inodes in from disk.
316 		 */
317 		if (sblock.fs_flags & FS_DOSOFTDEP) {
318 			if (!cg_chkmagic(&cgblk))
319 				errx(1, "CG %d: BAD MAGIC NUMBER\n", cg);
320 			cp = &cg_inosused(&cgblk)[(inosused - 1) / CHAR_BIT];
321 			for ( ; inosused > 0; inosused -= CHAR_BIT, cp--) {
322 				if (*cp == 0)
323 					continue;
324 				for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
325 					if (*cp & i)
326 						break;
327 					inosused--;
328 				}
329 				break;
330 			}
331 			if (inosused <= 0)
332 				continue;
333 		}
334 		for (i = 0; i < inosused; i++, ino++) {
335 			if ((dp = getnextinode(ino)) == NULL || ino < ROOTINO ||
336 			    (mode = DIP(dp, di_mode) & IFMT) == 0)
337 				continue;
338 			if (qnp->flags & HASGRP) {
339 				fup = addid((u_long)DIP(dp, di_gid), GRPQUOTA,
340 				    (char *)0);
341 				fup->fu_curinodes++;
342 				if (mode == IFREG || mode == IFDIR ||
343 				    mode == IFLNK)
344 					fup->fu_curblocks += DIP(dp, di_blocks);
345 			}
346 			if (qnp->flags & HASUSR) {
347 				fup = addid((u_long)DIP(dp, di_uid), USRQUOTA,
348 				    (char *)0);
349 				fup->fu_curinodes++;
350 				if (mode == IFREG || mode == IFDIR ||
351 				    mode == IFLNK)
352 					fup->fu_curblocks += DIP(dp, di_blocks);
353 			}
354 		}
355 	}
356 	freeinodebuf();
357 	if (qnp->flags & HASUSR)
358 		errs += update(mntpt, qnp->usrqfname, USRQUOTA);
359 	if (qnp->flags & HASGRP)
360 		errs += update(mntpt, qnp->grpqfname, GRPQUOTA);
361 	close(fi);
362 	return (errs);
363 }
364 
365 /*
366  * Update a specified quota file.
367  */
368 int
369 update(fsname, quotafile, type)
370 	char *fsname, *quotafile;
371 	int type;
372 {
373 	struct fileusage *fup;
374 	FILE *qfi, *qfo;
375 	u_long id, lastid;
376 	off_t offset;
377 	struct dqblk dqbuf;
378 	static int warned = 0;
379 	static struct dqblk zerodqbuf;
380 	static struct fileusage zerofileusage;
381 
382 	if ((qfo = fopen(quotafile, "r+")) == NULL) {
383 		if (errno == ENOENT)
384 			qfo = fopen(quotafile, "w+");
385 		if (qfo) {
386 			warnx("creating quota file %s", quotafile);
387 #define	MODE	(S_IRUSR|S_IWUSR|S_IRGRP)
388 			(void) fchown(fileno(qfo), getuid(), getquotagid());
389 			(void) fchmod(fileno(qfo), MODE);
390 		} else {
391 			warn("%s", quotafile);
392 			return (1);
393 		}
394 	}
395 	if ((qfi = fopen(quotafile, "r")) == NULL) {
396 		warn("%s", quotafile);
397 		(void) fclose(qfo);
398 		return (1);
399 	}
400 	if (quotactl(fsname, QCMD(Q_SYNC, type), (u_long)0, (caddr_t)0) < 0 &&
401 	    errno == EOPNOTSUPP && !warned && vflag) {
402 		warned++;
403 		(void)printf("*** Warning: %s\n",
404 		    "Quotas are not compiled into this kernel");
405 	}
406 	for (lastid = highid[type], id = 0, offset = 0; id <= lastid;
407 	    id++, offset += sizeof(struct dqblk)) {
408 		if (fread((char *)&dqbuf, sizeof(struct dqblk), 1, qfi) == 0)
409 			dqbuf = zerodqbuf;
410 		if ((fup = lookup(id, type)) == 0)
411 			fup = &zerofileusage;
412 		if (dqbuf.dqb_curinodes == fup->fu_curinodes &&
413 		    dqbuf.dqb_curblocks == fup->fu_curblocks) {
414 			fup->fu_curinodes = 0;
415 			fup->fu_curblocks = 0;
416 			continue;
417 		}
418 		if (vflag) {
419 			if (aflag)
420 				printf("%s: ", fsname);
421 			printf("%-8s fixed:", fup->fu_name);
422 			if (dqbuf.dqb_curinodes != fup->fu_curinodes)
423 				(void)printf("\tinodes %lu -> %lu",
424 				    (u_long)dqbuf.dqb_curinodes,
425 				    (u_long)fup->fu_curinodes);
426 			if (dqbuf.dqb_curblocks != fup->fu_curblocks)
427 				(void)printf("\tblocks %lu -> %lu",
428 				    (u_long)dqbuf.dqb_curblocks,
429 				    (u_long)fup->fu_curblocks);
430 			(void)printf("\n");
431 		}
432 		/*
433 		 * Reset time limit if have a soft limit and were
434 		 * previously under it, but are now over it.
435 		 */
436 		if (dqbuf.dqb_bsoftlimit &&
437 		    dqbuf.dqb_curblocks < dqbuf.dqb_bsoftlimit &&
438 		    fup->fu_curblocks >= dqbuf.dqb_bsoftlimit)
439 			dqbuf.dqb_btime = 0;
440 		if (dqbuf.dqb_isoftlimit &&
441 		    dqbuf.dqb_curblocks < dqbuf.dqb_isoftlimit &&
442 		    fup->fu_curblocks >= dqbuf.dqb_isoftlimit)
443 			dqbuf.dqb_itime = 0;
444 		dqbuf.dqb_curinodes = fup->fu_curinodes;
445 		dqbuf.dqb_curblocks = fup->fu_curblocks;
446 		if (fseek(qfo, offset, SEEK_SET) < 0) {
447 			warn("%s: seek failed", quotafile);
448 			return(1);
449 		}
450 		fwrite((char *)&dqbuf, sizeof(struct dqblk), 1, qfo);
451 		(void) quotactl(fsname, QCMD(Q_SETUSE, type), id,
452 		    (caddr_t)&dqbuf);
453 		fup->fu_curinodes = 0;
454 		fup->fu_curblocks = 0;
455 	}
456 	fclose(qfi);
457 	fflush(qfo);
458 	ftruncate(fileno(qfo),
459 	    (((off_t)highid[type] + 1) * sizeof(struct dqblk)));
460 	fclose(qfo);
461 	return (0);
462 }
463 
464 /*
465  * Check to see if target appears in list of size cnt.
466  */
467 int
468 oneof(target, list, cnt)
469 	char *target, *list[];
470 	int cnt;
471 {
472 	int i;
473 
474 	for (i = 0; i < cnt; i++)
475 		if (strcmp(target, list[i]) == 0)
476 			return (i);
477 	return (-1);
478 }
479 
480 /*
481  * Determine the group identifier for quota files.
482  */
483 int
484 getquotagid()
485 {
486 	struct group *gr;
487 
488 	if ((gr = getgrnam(quotagroup)) != NULL)
489 		return (gr->gr_gid);
490 	return (-1);
491 }
492 
493 /*
494  * Check to see if a particular quota is to be enabled.
495  */
496 int
497 hasquota(fs, type, qfnamep)
498 	struct fstab *fs;
499 	int type;
500 	char **qfnamep;
501 {
502 	char *opt;
503 	char *cp;
504 	static char initname, usrname[100], grpname[100];
505 	static char buf[BUFSIZ];
506 
507 	if (!initname) {
508 		(void)snprintf(usrname, sizeof(usrname),
509 		    "%s%s", qfextension[USRQUOTA], qfname);
510 		(void)snprintf(grpname, sizeof(grpname),
511 		    "%s%s", qfextension[GRPQUOTA], qfname);
512 		initname = 1;
513 	}
514 	strcpy(buf, fs->fs_mntops);
515 	for (opt = strtok(buf, ","); opt; opt = strtok(NULL, ",")) {
516 		if ((cp = index(opt, '=')) != NULL)
517 			*cp++ = '\0';
518 		if (type == USRQUOTA && strcmp(opt, usrname) == 0)
519 			break;
520 		if (type == GRPQUOTA && strcmp(opt, grpname) == 0)
521 			break;
522 	}
523 	if (!opt)
524 		return (0);
525 	if (cp)
526 		*qfnamep = cp;
527 	else {
528 		(void)snprintf(buf, sizeof(buf),
529 		    "%s/%s.%s", fs->fs_file, qfname, qfextension[type]);
530 		*qfnamep = buf;
531 	}
532 	return (1);
533 }
534 
535 /*
536  * Routines to manage the file usage table.
537  *
538  * Lookup an id of a specific type.
539  */
540 struct fileusage *
541 lookup(id, type)
542 	u_long id;
543 	int type;
544 {
545 	struct fileusage *fup;
546 
547 	for (fup = fuhead[type][id & (FUHASH-1)]; fup != 0; fup = fup->fu_next)
548 		if (fup->fu_id == id)
549 			return (fup);
550 	return (NULL);
551 }
552 
553 /*
554  * Add a new file usage id if it does not already exist.
555  */
556 struct fileusage *
557 addid(id, type, name)
558 	u_long id;
559 	int type;
560 	char *name;
561 {
562 	struct fileusage *fup, **fhp;
563 	int len;
564 
565 	if ((fup = lookup(id, type)) != NULL)
566 		return (fup);
567 	if (name)
568 		len = strlen(name);
569 	else
570 		len = 10;
571 	if ((fup = calloc(1, sizeof(*fup) + len)) == NULL)
572 		errx(1, "calloc failed");
573 	fhp = &fuhead[type][id & (FUHASH - 1)];
574 	fup->fu_next = *fhp;
575 	*fhp = fup;
576 	fup->fu_id = id;
577 	if (id > highid[type])
578 		highid[type] = id;
579 	if (name)
580 		bcopy(name, fup->fu_name, len + 1);
581 	else {
582 		(void)sprintf(fup->fu_name, "%lu", id);
583 		if (vflag)
584 			printf("unknown %cid: %lu\n",
585 			    type == USRQUOTA ? 'u' : 'g', id);
586 	}
587 	return (fup);
588 }
589 
590 /*
591  * Special purpose version of ginode used to optimize pass
592  * over all the inodes in numerical order.
593  */
594 static ino_t nextino, lastinum, lastvalidinum;
595 static long readcnt, readpercg, fullcnt, inobufsize, partialcnt, partialsize;
596 static caddr_t inodebuf;
597 #define INOBUFSIZE	56*1024		/* size of buffer to read inodes */
598 
599 union dinode *
600 getnextinode(ino_t inumber)
601 {
602 	long size;
603 	ufs2_daddr_t dblk;
604 	union dinode *dp;
605 	static caddr_t nextinop;
606 
607 	if (inumber != nextino++ || inumber > lastvalidinum)
608 		errx(1, "bad inode number %d to nextinode", inumber);
609 	if (inumber >= lastinum) {
610 		readcnt++;
611 		dblk = fsbtodb(&sblock, ino_to_fsba(&sblock, lastinum));
612 		if (readcnt % readpercg == 0) {
613 			size = partialsize;
614 			lastinum += partialcnt;
615 		} else {
616 			size = inobufsize;
617 			lastinum += fullcnt;
618 		}
619 		/*
620 		 * If bread returns an error, it will already have zeroed
621 		 * out the buffer, so we do not need to do so here.
622 		 */
623 		bread(dblk, inodebuf, size);
624 		nextinop = inodebuf;
625 	}
626 	dp = (union dinode *)nextinop;
627 	if (sblock.fs_magic == FS_UFS1_MAGIC)
628 		nextinop += sizeof(struct ufs1_dinode);
629 	else
630 		nextinop += sizeof(struct ufs2_dinode);
631 	return (dp);
632 }
633 
634 /*
635  * Prepare to scan a set of inodes.
636  */
637 void
638 setinodebuf(ino_t inum)
639 {
640 
641 	if (inum % sblock.fs_ipg != 0)
642 		errx(1, "bad inode number %d to setinodebuf", inum);
643 	lastvalidinum = inum + sblock.fs_ipg - 1;
644 	nextino = inum;
645 	lastinum = inum;
646 	readcnt = 0;
647 	if (inodebuf != NULL)
648 		return;
649 	inobufsize = blkroundup(&sblock, INOBUFSIZE);
650 	fullcnt = inobufsize / ((sblock.fs_magic == FS_UFS1_MAGIC) ?
651 	    sizeof(struct ufs1_dinode) : sizeof(struct ufs2_dinode));
652 	readpercg = sblock.fs_ipg / fullcnt;
653 	partialcnt = sblock.fs_ipg % fullcnt;
654 	partialsize = partialcnt * ((sblock.fs_magic == FS_UFS1_MAGIC) ?
655 	    sizeof(struct ufs1_dinode) : sizeof(struct ufs2_dinode));
656 	if (partialcnt != 0) {
657 		readpercg++;
658 	} else {
659 		partialcnt = fullcnt;
660 		partialsize = inobufsize;
661 	}
662 	if ((inodebuf = malloc((unsigned)inobufsize)) == NULL)
663 		errx(1, "cannot allocate space for inode buffer");
664 }
665 
666 /*
667  * Free up data structures used to scan inodes.
668  */
669 void
670 freeinodebuf()
671 {
672 
673 	if (inodebuf != NULL)
674 		free(inodebuf);
675 	inodebuf = NULL;
676 }
677 
678 /*
679  * Read specified disk blocks.
680  */
681 void
682 bread(bno, buf, cnt)
683 	ufs2_daddr_t bno;
684 	char *buf;
685 	long cnt;
686 {
687 
688 	if (lseek(fi, (off_t)bno * dev_bsize, SEEK_SET) < 0 ||
689 	    read(fi, buf, cnt) != cnt)
690 		errx(1, "bread failed on block %ld", (long)bno);
691 }
692