xref: /freebsd/sbin/fsck_ffs/pass5.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1980, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/param.h>
33 #include <sys/sysctl.h>
34 
35 #include <ufs/ufs/dinode.h>
36 #include <ufs/ffs/fs.h>
37 
38 #include <err.h>
39 #include <inttypes.h>
40 #include <limits.h>
41 #include <string.h>
42 
43 #include "fsck.h"
44 
45 static void check_maps(u_char *, u_char *, int, ufs2_daddr_t, const char *,
46 			int *, int, int, int);
47 static void clear_blocks(ufs2_daddr_t start, ufs2_daddr_t end);
48 
49 void
50 pass5(void)
51 {
52 	int c, i, j, blk, frags, basesize, mapsize;
53 	int inomapsize, blkmapsize;
54 	struct fs *fs = &sblock;
55 	ufs2_daddr_t d, dbase, dmax, start;
56 	int rewritecg = 0;
57 	ino_t inum;
58 	struct csum *cs;
59 	struct csum_total cstotal;
60 	struct inodesc idesc[3];
61 	char buf[MAXBSIZE];
62 	struct cg *cg, *newcg = (struct cg *)buf;
63 	struct bufarea *cgbp;
64 
65 	inoinfo(UFS_WINO)->ino_state = USTATE;
66 	memset(newcg, 0, (size_t)fs->fs_cgsize);
67 	newcg->cg_niblk = fs->fs_ipg;
68 	/* check to see if we are to add a cylinder group check hash */
69 	if ((ckhashadd & CK_CYLGRP) != 0)
70 		rewritecg = 1;
71 	if (cvtlevel >= 3) {
72 		if (fs->fs_maxcontig < 2 && fs->fs_contigsumsize > 0) {
73 			if (preen)
74 				pwarn("DELETING CLUSTERING MAPS\n");
75 			if (preen || reply("DELETE CLUSTERING MAPS")) {
76 				fs->fs_contigsumsize = 0;
77 				rewritecg = 1;
78 				sbdirty();
79 			}
80 		}
81 		if (fs->fs_maxcontig > 1) {
82 			const char *doit = NULL;
83 
84 			if (fs->fs_contigsumsize < 1) {
85 				doit = "CREAT";
86 			} else if (fs->fs_contigsumsize < fs->fs_maxcontig &&
87 				   fs->fs_contigsumsize < FS_MAXCONTIG) {
88 				doit = "EXPAND";
89 			}
90 			if (doit) {
91 				i = fs->fs_contigsumsize;
92 				fs->fs_contigsumsize =
93 				    MIN(fs->fs_maxcontig, FS_MAXCONTIG);
94 				if (CGSIZE(fs) > (u_int)fs->fs_bsize) {
95 					pwarn("CANNOT %s CLUSTER MAPS\n", doit);
96 					fs->fs_contigsumsize = i;
97 				} else if (preen ||
98 				    reply("CREATE CLUSTER MAPS")) {
99 					if (preen)
100 						pwarn("%sING CLUSTER MAPS\n",
101 						    doit);
102 					fs->fs_cgsize =
103 					    fragroundup(fs, CGSIZE(fs));
104 					rewritecg = 1;
105 					sbdirty();
106 				}
107 			}
108 		}
109 	}
110 	basesize = sizeof(*newcg);
111 	if (sblock.fs_magic == FS_UFS2_MAGIC) {
112 		newcg->cg_iusedoff = basesize;
113 	} else {
114 		/*
115 		 * We reserve the space for the old rotation summary
116 		 * tables for the benefit of old kernels, but do not
117 		 * maintain them in modern kernels. In time, they can
118 		 * go away.
119 		 */
120 		newcg->cg_old_btotoff = basesize;
121 		newcg->cg_old_boff = newcg->cg_old_btotoff +
122 		    fs->fs_old_cpg * sizeof(int32_t);
123 		newcg->cg_iusedoff = newcg->cg_old_boff +
124 		    fs->fs_old_cpg * fs->fs_old_nrpos * sizeof(u_int16_t);
125 		memset(&newcg[1], 0, newcg->cg_iusedoff - basesize);
126 	}
127 	inomapsize = howmany(fs->fs_ipg, CHAR_BIT);
128 	newcg->cg_freeoff = newcg->cg_iusedoff + inomapsize;
129 	blkmapsize = howmany(fs->fs_fpg, CHAR_BIT);
130 	newcg->cg_nextfreeoff = newcg->cg_freeoff + blkmapsize;
131 	if (fs->fs_contigsumsize > 0) {
132 		newcg->cg_clustersumoff = newcg->cg_nextfreeoff -
133 		    sizeof(u_int32_t);
134 		newcg->cg_clustersumoff =
135 		    roundup(newcg->cg_clustersumoff, sizeof(u_int32_t));
136 		newcg->cg_clusteroff = newcg->cg_clustersumoff +
137 		    (fs->fs_contigsumsize + 1) * sizeof(u_int32_t);
138 		newcg->cg_nextfreeoff = newcg->cg_clusteroff +
139 		    howmany(fragstoblks(fs, fs->fs_fpg), CHAR_BIT);
140 	}
141 	newcg->cg_magic = CG_MAGIC;
142 	mapsize = newcg->cg_nextfreeoff - newcg->cg_iusedoff;
143 	memset(&idesc[0], 0, sizeof idesc);
144 	for (i = 0; i < 3; i++)
145 		idesc[i].id_type = ADDR;
146 	memset(&cstotal, 0, sizeof(struct csum_total));
147 	dmax = blknum(fs, fs->fs_size + fs->fs_frag - 1);
148 	for (d = fs->fs_size; d < dmax; d++)
149 		setbmap(d);
150 	for (c = 0; c < fs->fs_ncg; c++) {
151 		if (got_siginfo) {
152 			printf("%s: phase 5: cyl group %d of %d (%d%%)\n",
153 			    cdevname, c, sblock.fs_ncg,
154 			    c * 100 / sblock.fs_ncg);
155 			got_siginfo = 0;
156 		}
157 		if (got_sigalarm) {
158 			setproctitle("%s p5 %d%%", cdevname,
159 			    c * 100 / sblock.fs_ncg);
160 			got_sigalarm = 0;
161 		}
162 		cgbp = cglookup(c);
163 		cg = cgbp->b_un.b_cg;
164 		if (!cg_chkmagic(cg))
165 			pfatal("CG %d: BAD MAGIC NUMBER\n", c);
166 		/*
167 		 * If we have a cylinder group check hash and are not adding
168 		 * it for the first time, verify that it is good.
169 		 */
170 		if ((fs->fs_metackhash & CK_CYLGRP) != 0 &&
171 		    (ckhashadd & CK_CYLGRP) == 0) {
172 			uint32_t ckhash, thishash;
173 
174 			ckhash = cg->cg_ckhash;
175 			cg->cg_ckhash = 0;
176 			thishash = calculate_crc32c(~0L, cg, fs->fs_cgsize);
177 			if (ckhash == thishash) {
178 				cg->cg_ckhash = ckhash;
179 			} else {
180 				pwarn("CG %d: BAD CHECK-HASH %#x vs %#x\n",
181 				    c, ckhash, thishash);
182 				cg->cg_ckhash = thishash;
183 				cgdirty(cgbp);
184 			}
185 		}
186 		newcg->cg_time = cg->cg_time;
187 		newcg->cg_old_time = cg->cg_old_time;
188 		newcg->cg_unrefs = cg->cg_unrefs;
189 		newcg->cg_ckhash = cg->cg_ckhash;
190 		newcg->cg_cgx = c;
191 		dbase = cgbase(fs, c);
192 		dmax = dbase + fs->fs_fpg;
193 		if (dmax > fs->fs_size)
194 			dmax = fs->fs_size;
195 		newcg->cg_ndblk = dmax - dbase;
196 		if (fs->fs_magic == FS_UFS1_MAGIC) {
197 			if (c == fs->fs_ncg - 1)
198 				newcg->cg_old_ncyl = howmany(newcg->cg_ndblk,
199 				    fs->fs_fpg / fs->fs_old_cpg);
200 			else
201 				newcg->cg_old_ncyl = fs->fs_old_cpg;
202 			newcg->cg_old_niblk = fs->fs_ipg;
203 			newcg->cg_niblk = 0;
204 		}
205 		if (fs->fs_contigsumsize > 0)
206 			newcg->cg_nclusterblks = newcg->cg_ndblk / fs->fs_frag;
207 		newcg->cg_cs.cs_ndir = 0;
208 		newcg->cg_cs.cs_nffree = 0;
209 		newcg->cg_cs.cs_nbfree = 0;
210 		newcg->cg_cs.cs_nifree = fs->fs_ipg;
211 		if (cg->cg_rotor >= 0 && cg->cg_rotor < newcg->cg_ndblk)
212 			newcg->cg_rotor = cg->cg_rotor;
213 		else
214 			newcg->cg_rotor = 0;
215 		if (cg->cg_frotor >= 0 && cg->cg_frotor < newcg->cg_ndblk)
216 			newcg->cg_frotor = cg->cg_frotor;
217 		else
218 			newcg->cg_frotor = 0;
219 		if (cg->cg_irotor >= 0 && cg->cg_irotor < fs->fs_ipg)
220 			newcg->cg_irotor = cg->cg_irotor;
221 		else
222 			newcg->cg_irotor = 0;
223 		if (fs->fs_magic == FS_UFS1_MAGIC) {
224 			newcg->cg_initediblk = 0;
225 		} else {
226 			if ((unsigned)cg->cg_initediblk > fs->fs_ipg)
227 				newcg->cg_initediblk = fs->fs_ipg;
228 			else
229 				newcg->cg_initediblk = cg->cg_initediblk;
230 		}
231 		memset(&newcg->cg_frsum[0], 0, sizeof newcg->cg_frsum);
232 		memset(cg_inosused(newcg), 0, (size_t)(mapsize));
233 		inum = fs->fs_ipg * c;
234 		for (i = 0; i < inostathead[c].il_numalloced; inum++, i++) {
235 			switch (inoinfo(inum)->ino_state) {
236 
237 			case USTATE:
238 				break;
239 
240 			case DSTATE:
241 			case DCLEAR:
242 			case DFOUND:
243 			case DZLINK:
244 				newcg->cg_cs.cs_ndir++;
245 				/* FALLTHROUGH */
246 
247 			case FSTATE:
248 			case FCLEAR:
249 			case FZLINK:
250 				newcg->cg_cs.cs_nifree--;
251 				setbit(cg_inosused(newcg), i);
252 				break;
253 
254 			default:
255 				if (inum < UFS_ROOTINO)
256 					break;
257 				errx(EEXIT, "BAD STATE %d FOR INODE I=%ju",
258 				    inoinfo(inum)->ino_state, (uintmax_t)inum);
259 			}
260 		}
261 		if (c == 0)
262 			for (i = 0; i < (int)UFS_ROOTINO; i++) {
263 				setbit(cg_inosused(newcg), i);
264 				newcg->cg_cs.cs_nifree--;
265 			}
266 		start = -1;
267 		for (i = 0, d = dbase;
268 		     d < dmax;
269 		     d += fs->fs_frag, i += fs->fs_frag) {
270 			frags = 0;
271 			for (j = 0; j < fs->fs_frag; j++) {
272 				if (testbmap(d + j)) {
273 					if ((Eflag || Zflag) && start != -1) {
274 						clear_blocks(start, d + j - 1);
275 						start = -1;
276 					}
277 					continue;
278 				}
279 				if (start == -1)
280 					start = d + j;
281 				setbit(cg_blksfree(newcg), i + j);
282 				frags++;
283 			}
284 			if (frags == fs->fs_frag) {
285 				newcg->cg_cs.cs_nbfree++;
286 				if (fs->fs_contigsumsize > 0)
287 					setbit(cg_clustersfree(newcg),
288 					    i / fs->fs_frag);
289 			} else if (frags > 0) {
290 				newcg->cg_cs.cs_nffree += frags;
291 				blk = blkmap(fs, cg_blksfree(newcg), i);
292 				ffs_fragacct(fs, blk, newcg->cg_frsum, 1);
293 			}
294 		}
295 		if ((Eflag || Zflag) && start != -1)
296 			clear_blocks(start, d - 1);
297 		if (fs->fs_contigsumsize > 0) {
298 			int32_t *sump = cg_clustersum(newcg);
299 			u_char *mapp = cg_clustersfree(newcg);
300 			int map = *mapp++;
301 			int bit = 1;
302 			int run = 0;
303 
304 			for (i = 0; i < newcg->cg_nclusterblks; i++) {
305 				if ((map & bit) != 0) {
306 					run++;
307 				} else if (run != 0) {
308 					if (run > fs->fs_contigsumsize)
309 						run = fs->fs_contigsumsize;
310 					sump[run]++;
311 					run = 0;
312 				}
313 				if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
314 					bit <<= 1;
315 				} else {
316 					map = *mapp++;
317 					bit = 1;
318 				}
319 			}
320 			if (run != 0) {
321 				if (run > fs->fs_contigsumsize)
322 					run = fs->fs_contigsumsize;
323 				sump[run]++;
324 			}
325 		}
326 
327 		if (bkgrdflag != 0) {
328 			cstotal.cs_nffree += cg->cg_cs.cs_nffree;
329 			cstotal.cs_nbfree += cg->cg_cs.cs_nbfree;
330 			cstotal.cs_nifree += cg->cg_cs.cs_nifree;
331 			cstotal.cs_ndir += cg->cg_cs.cs_ndir;
332 		} else {
333 			cstotal.cs_nffree += newcg->cg_cs.cs_nffree;
334 			cstotal.cs_nbfree += newcg->cg_cs.cs_nbfree;
335 			cstotal.cs_nifree += newcg->cg_cs.cs_nifree;
336 			cstotal.cs_ndir += newcg->cg_cs.cs_ndir;
337 		}
338 		cs = &fs->fs_cs(fs, c);
339 		if (cursnapshot == 0 &&
340 		    memcmp(&newcg->cg_cs, cs, sizeof *cs) != 0 &&
341 		    dofix(&idesc[0], "FREE BLK COUNT(S) WRONG IN SUPERBLK")) {
342 			memmove(cs, &newcg->cg_cs, sizeof *cs);
343 			sbdirty();
344 		}
345 		if (rewritecg) {
346 			memmove(cg, newcg, (size_t)fs->fs_cgsize);
347 			cgdirty(cgbp);
348 			continue;
349 		}
350 		if (cursnapshot == 0 &&
351 		    memcmp(newcg, cg, basesize) != 0 &&
352 		    dofix(&idesc[2], "SUMMARY INFORMATION BAD")) {
353 			memmove(cg, newcg, (size_t)basesize);
354 			cgdirty(cgbp);
355 		}
356 		if (bkgrdflag != 0 || usedsoftdep || debug)
357 			update_maps(cg, newcg, bkgrdflag);
358 		if (cursnapshot == 0 &&
359 		    memcmp(cg_inosused(newcg), cg_inosused(cg), mapsize) != 0 &&
360 		    dofix(&idesc[1], "BLK(S) MISSING IN BIT MAPS")) {
361 			memmove(cg_inosused(cg), cg_inosused(newcg),
362 			      (size_t)mapsize);
363 			cgdirty(cgbp);
364 		}
365 	}
366 	if (cursnapshot == 0 &&
367 	    memcmp(&cstotal, &fs->fs_cstotal, sizeof cstotal) != 0
368 	    && dofix(&idesc[0], "SUMMARY BLK COUNT(S) WRONG IN SUPERBLK")) {
369 		if (debug) {
370 			printf("cstotal is currently: %jd dirs, %jd blks free, "
371 			    "%jd frags free, %jd inos free, %jd clusters\n",
372 			    (intmax_t)fs->fs_cstotal.cs_ndir,
373 			    (intmax_t)fs->fs_cstotal.cs_nbfree,
374 			    (intmax_t)fs->fs_cstotal.cs_nffree,
375 			    (intmax_t)fs->fs_cstotal.cs_nifree,
376 			    (intmax_t)fs->fs_cstotal.cs_numclusters);
377 			printf("cstotal ought to be:  %jd dirs, %jd blks free, "
378 			    "%jd frags free, %jd inos free, %jd clusters\n",
379 			    (intmax_t)cstotal.cs_ndir,
380 			    (intmax_t)cstotal.cs_nbfree,
381 			    (intmax_t)cstotal.cs_nffree,
382 			    (intmax_t)cstotal.cs_nifree,
383 			    (intmax_t)cstotal.cs_numclusters);
384 		}
385 		memmove(&fs->fs_cstotal, &cstotal, sizeof cstotal);
386 		fs->fs_ronly = 0;
387 		fs->fs_fmod = 0;
388 		sbdirty();
389 	}
390 
391 	/*
392 	 * When doing background fsck on a snapshot, figure out whether
393 	 * the superblock summary is inaccurate and correct it when
394 	 * necessary.
395 	 */
396 	if (cursnapshot != 0) {
397 		cmd.size = 1;
398 
399 		cmd.value = cstotal.cs_ndir - fs->fs_cstotal.cs_ndir;
400 		if (cmd.value != 0) {
401 			if (debug)
402 				printf("adjndir by %+" PRIi64 "\n", cmd.value);
403 			if (bkgrdsumadj == 0 || sysctl(adjndir, MIBSIZE, 0, 0,
404 			    &cmd, sizeof cmd) == -1)
405 				rwerror("ADJUST NUMBER OF DIRECTORIES",
406 				    cmd.value);
407 		}
408 
409 		cmd.value = cstotal.cs_nbfree - fs->fs_cstotal.cs_nbfree;
410 		if (cmd.value != 0) {
411 			if (debug)
412 				printf("adjnbfree by %+" PRIi64 "\n",
413 				    cmd.value);
414 			if (bkgrdsumadj == 0 || sysctl(adjnbfree, MIBSIZE, 0, 0,
415 			    &cmd, sizeof cmd) == -1)
416 				rwerror("ADJUST NUMBER OF FREE BLOCKS",
417 				    cmd.value);
418 		}
419 
420 		cmd.value = cstotal.cs_nifree - fs->fs_cstotal.cs_nifree;
421 		if (cmd.value != 0) {
422 			if (debug)
423 				printf("adjnifree by %+" PRIi64 "\n",
424 				    cmd.value);
425 			if (bkgrdsumadj == 0 || sysctl(adjnifree, MIBSIZE, 0, 0,
426 			    &cmd, sizeof cmd) == -1)
427 				rwerror("ADJUST NUMBER OF FREE INODES",
428 				    cmd.value);
429 		}
430 
431 		cmd.value = cstotal.cs_nffree - fs->fs_cstotal.cs_nffree;
432 		if (cmd.value != 0) {
433 			if (debug)
434 				printf("adjnffree by %+" PRIi64 "\n",
435 				    cmd.value);
436 			if (bkgrdsumadj == 0 || sysctl(adjnffree, MIBSIZE, 0, 0,
437 			    &cmd, sizeof cmd) == -1)
438 				rwerror("ADJUST NUMBER OF FREE FRAGS",
439 				    cmd.value);
440 		}
441 
442 		cmd.value = cstotal.cs_numclusters -
443 		    fs->fs_cstotal.cs_numclusters;
444 		if (cmd.value != 0) {
445 			if (debug)
446 				printf("adjnumclusters by %+" PRIi64 "\n",
447 				    cmd.value);
448 			if (bkgrdsumadj == 0 || sysctl(adjnumclusters, MIBSIZE,
449 			    0, 0, &cmd, sizeof cmd) == -1)
450 				rwerror("ADJUST NUMBER OF FREE CLUSTERS",
451 				    cmd.value);
452 		}
453 	}
454 }
455 
456 /*
457  * Compare the original cylinder group inode and block bitmaps with the
458  * updated cylinder group inode and block bitmaps. Free inodes and blocks
459  * that have been added. Complain if any previously freed inodes blocks
460  * are now allocated.
461  */
462 void
463 update_maps(
464 	struct cg *oldcg,	/* cylinder group of claimed allocations */
465 	struct cg *newcg,	/* cylinder group of determined allocations */
466 	int usesysctl)		/* 1 => use sysctl interface to update maps */
467 {
468 	int inomapsize, excessdirs;
469 	struct fs *fs = &sblock;
470 
471 	inomapsize = howmany(fs->fs_ipg, CHAR_BIT);
472 	excessdirs = oldcg->cg_cs.cs_ndir - newcg->cg_cs.cs_ndir;
473 	if (excessdirs < 0) {
474 		pfatal("LOST %d DIRECTORIES\n", -excessdirs);
475 		excessdirs = 0;
476 	}
477 	if (excessdirs > 0)
478 		check_maps(cg_inosused(newcg), cg_inosused(oldcg), inomapsize,
479 		    oldcg->cg_cgx * (ufs2_daddr_t)fs->fs_ipg, "DIR", freedirs,
480 		    0, excessdirs, usesysctl);
481 	check_maps(cg_inosused(newcg), cg_inosused(oldcg), inomapsize,
482 	    oldcg->cg_cgx * (ufs2_daddr_t)fs->fs_ipg, "FILE", freefiles,
483 	    excessdirs, fs->fs_ipg, usesysctl);
484 	check_maps(cg_blksfree(oldcg), cg_blksfree(newcg),
485 	    howmany(fs->fs_fpg, CHAR_BIT),
486 	    oldcg->cg_cgx * (ufs2_daddr_t)fs->fs_fpg, "FRAG",
487 	    freeblks, 0, fs->fs_fpg, usesysctl);
488 }
489 
490 static void
491 check_maps(
492 	u_char *map1,	/* map of claimed allocations */
493 	u_char *map2,	/* map of determined allocations */
494 	int mapsize,	/* size of above two maps */
495 	ufs2_daddr_t startvalue, /* resource value for first element in map */
496 	const char *name,	/* name of resource found in maps */
497 	int *opcode,	/* sysctl opcode to free resource */
498 	int skip,	/* number of entries to skip before starting to free */
499 	int limit,	/* limit on number of entries to free */
500 	int usesysctl)	/* 1 => use sysctl interface to update maps */
501 {
502 #	define BUFSIZE 16
503 	char buf[BUFSIZE];
504 	long i, j, k, l, m, size;
505 	ufs2_daddr_t n, astart, aend, ustart, uend;
506 	void (*msg)(const char *fmt, ...);
507 
508 	if (usesysctl)
509 		msg = pfatal;
510 	else
511 		msg = pwarn;
512 	astart = ustart = aend = uend = -1;
513 	for (i = 0; i < mapsize; i++) {
514 		j = *map1++;
515 		k = *map2++;
516 		if (j == k)
517 			continue;
518 		for (m = 0, l = 1; m < CHAR_BIT; m++, l <<= 1) {
519 			if ((j & l) == (k & l))
520 				continue;
521 			n = startvalue + i * CHAR_BIT + m;
522 			if ((j & l) != 0) {
523 				if (astart == -1) {
524 					astart = aend = n;
525 					continue;
526 				}
527 				if (aend + 1 == n) {
528 					aend = n;
529 					continue;
530 				}
531 				if (astart == aend)
532 					(*msg)("ALLOCATED %s %" PRId64
533 					    " MARKED FREE\n",
534 					    name, astart);
535 				else
536 					(*msg)("%s %sS %" PRId64 "-%" PRId64
537 					    " MARKED FREE\n",
538 					    "ALLOCATED", name, astart, aend);
539 				astart = aend = n;
540 			} else {
541 				if (ustart == -1) {
542 					ustart = uend = n;
543 					continue;
544 				}
545 				if (uend + 1 == n) {
546 					uend = n;
547 					continue;
548 				}
549 				size = uend - ustart + 1;
550 				if (size <= skip) {
551 					skip -= size;
552 					ustart = uend = n;
553 					continue;
554 				}
555 				if (skip > 0) {
556 					ustart += skip;
557 					size -= skip;
558 					skip = 0;
559 				}
560 				if (size > limit)
561 					size = limit;
562 				if (debug && size == 1)
563 					pwarn("%s %s %" PRId64
564 					    " MARKED USED\n",
565 					    "UNALLOCATED", name, ustart);
566 				else if (debug)
567 					pwarn("%s %sS %" PRId64 "-%" PRId64
568 					    " MARKED USED\n",
569 					    "UNALLOCATED", name, ustart,
570 					    ustart + size - 1);
571 				if (usesysctl != 0) {
572 					cmd.value = ustart;
573 					cmd.size = size;
574 					if (sysctl(opcode, MIBSIZE, 0, 0,
575 					    &cmd, sizeof cmd) == -1) {
576 						snprintf(buf, BUFSIZE,
577 						    "FREE %s", name);
578 						rwerror(buf, cmd.value);
579 					}
580 				}
581 				limit -= size;
582 				if (limit <= 0)
583 					return;
584 				ustart = uend = n;
585 			}
586 		}
587 	}
588 	if (astart != -1) {
589 		if (astart == aend)
590 			(*msg)("ALLOCATED %s %" PRId64
591 			    " MARKED FREE\n", name, astart);
592 		else
593 			(*msg)("ALLOCATED %sS %" PRId64 "-%" PRId64
594 			    " MARKED FREE\n",
595 			    name, astart, aend);
596 	}
597 	if (ustart != -1) {
598 		size = uend - ustart + 1;
599 		if (size <= skip)
600 			return;
601 		if (skip > 0) {
602 			ustart += skip;
603 			size -= skip;
604 		}
605 		if (size > limit)
606 			size = limit;
607 		if (debug) {
608 			if (size == 1)
609 				pwarn("UNALLOCATED %s %" PRId64
610 				    " MARKED USED\n",
611 				    name, ustart);
612 			else
613 				pwarn("UNALLOCATED %sS %" PRId64 "-%" PRId64
614 				    " MARKED USED\n",
615 				    name, ustart, ustart + size - 1);
616 		}
617 		if (usesysctl != 0) {
618 			cmd.value = ustart;
619 			cmd.size = size;
620 			if (sysctl(opcode, MIBSIZE, 0, 0, &cmd,
621 			    sizeof cmd) == -1) {
622 				snprintf(buf, BUFSIZE, "FREE %s", name);
623 				rwerror(buf, cmd.value);
624 			}
625 		}
626 	}
627 }
628 
629 static void
630 clear_blocks(ufs2_daddr_t start, ufs2_daddr_t end)
631 {
632 
633 	if (debug)
634 		printf("Zero frags %jd to %jd\n", start, end);
635 	if (Zflag)
636 		blzero(fswritefd, fsbtodb(&sblock, start),
637 		    lfragtosize(&sblock, end - start + 1));
638 	if (Eflag)
639 		blerase(fswritefd, fsbtodb(&sblock, start),
640 		    lfragtosize(&sblock, end - start + 1));
641 }
642