xref: /freebsd/sys/ufs/ffs/ffs_alloc.c (revision 315ee00f)
1 /*-
2  * SPDX-License-Identifier: (BSD-2-Clause AND BSD-3-Clause)
3  *
4  * Copyright (c) 2002 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project by Marshall
8  * Kirk McKusick and Network Associates Laboratories, the Security
9  * Research Division of Network Associates, Inc. under DARPA/SPAWAR
10  * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
11  * research program
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
23  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
26  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  *
34  * Copyright (c) 1982, 1986, 1989, 1993
35  *	The Regents of the University of California.  All rights reserved.
36  *
37  * Redistribution and use in source and binary forms, with or without
38  * modification, are permitted provided that the following conditions
39  * are met:
40  * 1. Redistributions of source code must retain the above copyright
41  *    notice, this list of conditions and the following disclaimer.
42  * 2. Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in the
44  *    documentation and/or other materials provided with the distribution.
45  * 3. Neither the name of the University nor the names of its contributors
46  *    may be used to endorse or promote products derived from this software
47  *    without specific prior written permission.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
50  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
51  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
52  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
53  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
54  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
55  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
56  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
57  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
58  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
59  * SUCH DAMAGE.
60  *
61  *	@(#)ffs_alloc.c	8.18 (Berkeley) 5/26/95
62  */
63 
64 #include <sys/cdefs.h>
65 #include "opt_quota.h"
66 
67 #include <sys/param.h>
68 #include <sys/systm.h>
69 #include <sys/bio.h>
70 #include <sys/buf.h>
71 #include <sys/capsicum.h>
72 #include <sys/conf.h>
73 #include <sys/fcntl.h>
74 #include <sys/file.h>
75 #include <sys/filedesc.h>
76 #include <sys/gsb_crc32.h>
77 #include <sys/kernel.h>
78 #include <sys/mount.h>
79 #include <sys/priv.h>
80 #include <sys/proc.h>
81 #include <sys/stat.h>
82 #include <sys/syscallsubr.h>
83 #include <sys/sysctl.h>
84 #include <sys/syslog.h>
85 #include <sys/taskqueue.h>
86 #include <sys/vnode.h>
87 
88 #include <security/audit/audit.h>
89 
90 #include <geom/geom.h>
91 #include <geom/geom_vfs.h>
92 
93 #include <ufs/ufs/dir.h>
94 #include <ufs/ufs/extattr.h>
95 #include <ufs/ufs/quota.h>
96 #include <ufs/ufs/inode.h>
97 #include <ufs/ufs/ufs_extern.h>
98 #include <ufs/ufs/ufsmount.h>
99 
100 #include <ufs/ffs/fs.h>
101 #include <ufs/ffs/ffs_extern.h>
102 #include <ufs/ffs/softdep.h>
103 
104 typedef ufs2_daddr_t allocfcn_t(struct inode *ip, uint64_t cg,
105 				  ufs2_daddr_t bpref, int size, int rsize);
106 
107 static ufs2_daddr_t ffs_alloccg(struct inode *, uint64_t, ufs2_daddr_t, int,
108 				  int);
109 static ufs2_daddr_t
110 	      ffs_alloccgblk(struct inode *, struct buf *, ufs2_daddr_t, int);
111 static void	ffs_blkfree_cg(struct ufsmount *, struct fs *,
112 		    struct vnode *, ufs2_daddr_t, long, ino_t,
113 		    struct workhead *);
114 #ifdef INVARIANTS
115 static int	ffs_checkfreeblk(struct inode *, ufs2_daddr_t, long);
116 #endif
117 static void	ffs_checkcgintegrity(struct fs *, uint64_t, int);
118 static ufs2_daddr_t ffs_clusteralloc(struct inode *, uint64_t, ufs2_daddr_t,
119 				  int);
120 static ino_t	ffs_dirpref(struct inode *);
121 static ufs2_daddr_t ffs_fragextend(struct inode *, uint64_t, ufs2_daddr_t,
122 		    int, int);
123 static ufs2_daddr_t	ffs_hashalloc(struct inode *, uint64_t, ufs2_daddr_t,
124 		    int, int, allocfcn_t *);
125 static ufs2_daddr_t ffs_nodealloccg(struct inode *, uint64_t, ufs2_daddr_t, int,
126 		    int);
127 static ufs1_daddr_t ffs_mapsearch(struct fs *, struct cg *, ufs2_daddr_t, int);
128 static int	ffs_reallocblks_ufs1(struct vop_reallocblks_args *);
129 static int	ffs_reallocblks_ufs2(struct vop_reallocblks_args *);
130 static void	ffs_ckhash_cg(struct buf *);
131 
132 /*
133  * Allocate a block in the filesystem.
134  *
135  * The size of the requested block is given, which must be some
136  * multiple of fs_fsize and <= fs_bsize.
137  * A preference may be optionally specified. If a preference is given
138  * the following hierarchy is used to allocate a block:
139  *   1) allocate the requested block.
140  *   2) allocate a rotationally optimal block in the same cylinder.
141  *   3) allocate a block in the same cylinder group.
142  *   4) quadratically rehash into other cylinder groups, until an
143  *      available block is located.
144  * If no block preference is given the following hierarchy is used
145  * to allocate a block:
146  *   1) allocate a block in the cylinder group that contains the
147  *      inode for the file.
148  *   2) quadratically rehash into other cylinder groups, until an
149  *      available block is located.
150  */
151 int
152 ffs_alloc(struct inode *ip,
153 	ufs2_daddr_t lbn,
154 	ufs2_daddr_t bpref,
155 	int size,
156 	int flags,
157 	struct ucred *cred,
158 	ufs2_daddr_t *bnp)
159 {
160 	struct fs *fs;
161 	struct ufsmount *ump;
162 	ufs2_daddr_t bno;
163 	uint64_t cg, reclaimed;
164 	int64_t delta;
165 #ifdef QUOTA
166 	int error;
167 #endif
168 
169 	*bnp = 0;
170 	ump = ITOUMP(ip);
171 	fs = ump->um_fs;
172 	mtx_assert(UFS_MTX(ump), MA_OWNED);
173 #ifdef INVARIANTS
174 	if ((uint64_t)size > fs->fs_bsize || fragoff(fs, size) != 0) {
175 		printf("dev = %s, bsize = %ld, size = %d, fs = %s\n",
176 		    devtoname(ump->um_dev), (long)fs->fs_bsize, size,
177 		    fs->fs_fsmnt);
178 		panic("ffs_alloc: bad size");
179 	}
180 	if (cred == NOCRED)
181 		panic("ffs_alloc: missing credential");
182 #endif /* INVARIANTS */
183 	reclaimed = 0;
184 retry:
185 #ifdef QUOTA
186 	UFS_UNLOCK(ump);
187 	error = chkdq(ip, btodb(size), cred, 0);
188 	if (error)
189 		return (error);
190 	UFS_LOCK(ump);
191 #endif
192 	if (size == fs->fs_bsize && fs->fs_cstotal.cs_nbfree == 0)
193 		goto nospace;
194 	if (priv_check_cred(cred, PRIV_VFS_BLOCKRESERVE) &&
195 	    freespace(fs, fs->fs_minfree) - numfrags(fs, size) < 0)
196 		goto nospace;
197 	if (bpref >= fs->fs_size)
198 		bpref = 0;
199 	if (bpref == 0)
200 		cg = ino_to_cg(fs, ip->i_number);
201 	else
202 		cg = dtog(fs, bpref);
203 	bno = ffs_hashalloc(ip, cg, bpref, size, size, ffs_alloccg);
204 	if (bno > 0) {
205 		delta = btodb(size);
206 		DIP_SET(ip, i_blocks, DIP(ip, i_blocks) + delta);
207 		if (flags & IO_EXT)
208 			UFS_INODE_SET_FLAG(ip, IN_CHANGE);
209 		else
210 			UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_UPDATE);
211 		*bnp = bno;
212 		return (0);
213 	}
214 nospace:
215 #ifdef QUOTA
216 	UFS_UNLOCK(ump);
217 	/*
218 	 * Restore user's disk quota because allocation failed.
219 	 */
220 	(void) chkdq(ip, -btodb(size), cred, FORCE);
221 	UFS_LOCK(ump);
222 #endif
223 	if (reclaimed == 0 && (flags & IO_BUFLOCKED) == 0) {
224 		reclaimed = 1;
225 		softdep_request_cleanup(fs, ITOV(ip), cred, FLUSH_BLOCKS_WAIT);
226 		goto retry;
227 	}
228 	if (ffs_fsfail_cleanup_locked(ump, 0)) {
229 		UFS_UNLOCK(ump);
230 		return (ENXIO);
231 	}
232 	if (reclaimed > 0 &&
233 	    ppsratecheck(&ump->um_last_fullmsg, &ump->um_secs_fullmsg, 1)) {
234 		UFS_UNLOCK(ump);
235 		ffs_fserr(fs, ip->i_number, "filesystem full");
236 		uprintf("\n%s: write failed, filesystem is full\n",
237 		    fs->fs_fsmnt);
238 	} else {
239 		UFS_UNLOCK(ump);
240 	}
241 	return (ENOSPC);
242 }
243 
244 /*
245  * Reallocate a fragment to a bigger size
246  *
247  * The number and size of the old block is given, and a preference
248  * and new size is also specified. The allocator attempts to extend
249  * the original block. Failing that, the regular block allocator is
250  * invoked to get an appropriate block.
251  */
252 int
253 ffs_realloccg(struct inode *ip,
254 	ufs2_daddr_t lbprev,
255 	ufs2_daddr_t bprev,
256 	ufs2_daddr_t bpref,
257 	int osize,
258 	int nsize,
259 	int flags,
260 	struct ucred *cred,
261 	struct buf **bpp)
262 {
263 	struct vnode *vp;
264 	struct fs *fs;
265 	struct buf *bp;
266 	struct ufsmount *ump;
267 	uint64_t cg, request, reclaimed;
268 	int error, gbflags;
269 	ufs2_daddr_t bno;
270 	int64_t delta;
271 
272 	vp = ITOV(ip);
273 	ump = ITOUMP(ip);
274 	fs = ump->um_fs;
275 	bp = NULL;
276 	gbflags = (flags & BA_UNMAPPED) != 0 ? GB_UNMAPPED : 0;
277 #ifdef WITNESS
278 	gbflags |= IS_SNAPSHOT(ip) ? GB_NOWITNESS : 0;
279 #endif
280 
281 	mtx_assert(UFS_MTX(ump), MA_OWNED);
282 #ifdef INVARIANTS
283 	if (vp->v_mount->mnt_kern_flag & MNTK_SUSPENDED)
284 		panic("ffs_realloccg: allocation on suspended filesystem");
285 	if ((uint64_t)osize > fs->fs_bsize || fragoff(fs, osize) != 0 ||
286 	    (uint64_t)nsize > fs->fs_bsize || fragoff(fs, nsize) != 0) {
287 		printf(
288 		"dev = %s, bsize = %ld, osize = %d, nsize = %d, fs = %s\n",
289 		    devtoname(ump->um_dev), (long)fs->fs_bsize, osize,
290 		    nsize, fs->fs_fsmnt);
291 		panic("ffs_realloccg: bad size");
292 	}
293 	if (cred == NOCRED)
294 		panic("ffs_realloccg: missing credential");
295 #endif /* INVARIANTS */
296 	reclaimed = 0;
297 retry:
298 	if (priv_check_cred(cred, PRIV_VFS_BLOCKRESERVE) &&
299 	    freespace(fs, fs->fs_minfree) -  numfrags(fs, nsize - osize) < 0) {
300 		goto nospace;
301 	}
302 	if (bprev == 0) {
303 		printf("dev = %s, bsize = %ld, bprev = %jd, fs = %s\n",
304 		    devtoname(ump->um_dev), (long)fs->fs_bsize, (intmax_t)bprev,
305 		    fs->fs_fsmnt);
306 		panic("ffs_realloccg: bad bprev");
307 	}
308 	UFS_UNLOCK(ump);
309 	/*
310 	 * Allocate the extra space in the buffer.
311 	 */
312 	error = bread_gb(vp, lbprev, osize, NOCRED, gbflags, &bp);
313 	if (error) {
314 		return (error);
315 	}
316 
317 	if (bp->b_blkno == bp->b_lblkno) {
318 		if (lbprev >= UFS_NDADDR)
319 			panic("ffs_realloccg: lbprev out of range");
320 		bp->b_blkno = fsbtodb(fs, bprev);
321 	}
322 
323 #ifdef QUOTA
324 	error = chkdq(ip, btodb(nsize - osize), cred, 0);
325 	if (error) {
326 		brelse(bp);
327 		return (error);
328 	}
329 #endif
330 	/*
331 	 * Check for extension in the existing location.
332 	 */
333 	*bpp = NULL;
334 	cg = dtog(fs, bprev);
335 	UFS_LOCK(ump);
336 	bno = ffs_fragextend(ip, cg, bprev, osize, nsize);
337 	if (bno) {
338 		if (bp->b_blkno != fsbtodb(fs, bno))
339 			panic("ffs_realloccg: bad blockno");
340 		delta = btodb(nsize - osize);
341 		DIP_SET(ip, i_blocks, DIP(ip, i_blocks) + delta);
342 		if (flags & IO_EXT)
343 			UFS_INODE_SET_FLAG(ip, IN_CHANGE);
344 		else
345 			UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_UPDATE);
346 		allocbuf(bp, nsize);
347 		bp->b_flags |= B_DONE;
348 		vfs_bio_bzero_buf(bp, osize, nsize - osize);
349 		if ((bp->b_flags & (B_MALLOC | B_VMIO)) == B_VMIO)
350 			vfs_bio_set_valid(bp, osize, nsize - osize);
351 		*bpp = bp;
352 		return (0);
353 	}
354 	/*
355 	 * Allocate a new disk location.
356 	 */
357 	if (bpref >= fs->fs_size)
358 		bpref = 0;
359 	switch ((int)fs->fs_optim) {
360 	case FS_OPTSPACE:
361 		/*
362 		 * Allocate an exact sized fragment. Although this makes
363 		 * best use of space, we will waste time relocating it if
364 		 * the file continues to grow. If the fragmentation is
365 		 * less than half of the minimum free reserve, we choose
366 		 * to begin optimizing for time.
367 		 */
368 		request = nsize;
369 		if (fs->fs_minfree <= 5 ||
370 		    fs->fs_cstotal.cs_nffree >
371 		    (off_t)fs->fs_dsize * fs->fs_minfree / (2 * 100))
372 			break;
373 		log(LOG_NOTICE, "%s: optimization changed from SPACE to TIME\n",
374 			fs->fs_fsmnt);
375 		fs->fs_optim = FS_OPTTIME;
376 		break;
377 	case FS_OPTTIME:
378 		/*
379 		 * At this point we have discovered a file that is trying to
380 		 * grow a small fragment to a larger fragment. To save time,
381 		 * we allocate a full sized block, then free the unused portion.
382 		 * If the file continues to grow, the `ffs_fragextend' call
383 		 * above will be able to grow it in place without further
384 		 * copying. If aberrant programs cause disk fragmentation to
385 		 * grow within 2% of the free reserve, we choose to begin
386 		 * optimizing for space.
387 		 */
388 		request = fs->fs_bsize;
389 		if (fs->fs_cstotal.cs_nffree <
390 		    (off_t)fs->fs_dsize * (fs->fs_minfree - 2) / 100)
391 			break;
392 		log(LOG_NOTICE, "%s: optimization changed from TIME to SPACE\n",
393 			fs->fs_fsmnt);
394 		fs->fs_optim = FS_OPTSPACE;
395 		break;
396 	default:
397 		printf("dev = %s, optim = %ld, fs = %s\n",
398 		    devtoname(ump->um_dev), (long)fs->fs_optim, fs->fs_fsmnt);
399 		panic("ffs_realloccg: bad optim");
400 		/* NOTREACHED */
401 	}
402 	bno = ffs_hashalloc(ip, cg, bpref, request, nsize, ffs_alloccg);
403 	if (bno > 0) {
404 		bp->b_blkno = fsbtodb(fs, bno);
405 		if (!DOINGSOFTDEP(vp))
406 			/*
407 			 * The usual case is that a smaller fragment that
408 			 * was just allocated has been replaced with a bigger
409 			 * fragment or a full-size block. If it is marked as
410 			 * B_DELWRI, the current contents have not been written
411 			 * to disk. It is possible that the block was written
412 			 * earlier, but very uncommon. If the block has never
413 			 * been written, there is no need to send a BIO_DELETE
414 			 * for it when it is freed. The gain from avoiding the
415 			 * TRIMs for the common case of unwritten blocks far
416 			 * exceeds the cost of the write amplification for the
417 			 * uncommon case of failing to send a TRIM for a block
418 			 * that had been written.
419 			 */
420 			ffs_blkfree(ump, fs, ump->um_devvp, bprev, (long)osize,
421 			    ip->i_number, vp->v_type, NULL,
422 			    (bp->b_flags & B_DELWRI) != 0 ?
423 			    NOTRIM_KEY : SINGLETON_KEY);
424 		delta = btodb(nsize - osize);
425 		DIP_SET(ip, i_blocks, DIP(ip, i_blocks) + delta);
426 		if (flags & IO_EXT)
427 			UFS_INODE_SET_FLAG(ip, IN_CHANGE);
428 		else
429 			UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_UPDATE);
430 		allocbuf(bp, nsize);
431 		bp->b_flags |= B_DONE;
432 		vfs_bio_bzero_buf(bp, osize, nsize - osize);
433 		if ((bp->b_flags & (B_MALLOC | B_VMIO)) == B_VMIO)
434 			vfs_bio_set_valid(bp, osize, nsize - osize);
435 		*bpp = bp;
436 		return (0);
437 	}
438 #ifdef QUOTA
439 	UFS_UNLOCK(ump);
440 	/*
441 	 * Restore user's disk quota because allocation failed.
442 	 */
443 	(void) chkdq(ip, -btodb(nsize - osize), cred, FORCE);
444 	UFS_LOCK(ump);
445 #endif
446 nospace:
447 	/*
448 	 * no space available
449 	 */
450 	if (reclaimed == 0 && (flags & IO_BUFLOCKED) == 0) {
451 		reclaimed = 1;
452 		UFS_UNLOCK(ump);
453 		if (bp) {
454 			brelse(bp);
455 			bp = NULL;
456 		}
457 		UFS_LOCK(ump);
458 		softdep_request_cleanup(fs, vp, cred, FLUSH_BLOCKS_WAIT);
459 		goto retry;
460 	}
461 	if (bp)
462 		brelse(bp);
463 	if (ffs_fsfail_cleanup_locked(ump, 0)) {
464 		UFS_UNLOCK(ump);
465 		return (ENXIO);
466 	}
467 	if (reclaimed > 0 &&
468 	    ppsratecheck(&ump->um_last_fullmsg, &ump->um_secs_fullmsg, 1)) {
469 		UFS_UNLOCK(ump);
470 		ffs_fserr(fs, ip->i_number, "filesystem full");
471 		uprintf("\n%s: write failed, filesystem is full\n",
472 		    fs->fs_fsmnt);
473 	} else {
474 		UFS_UNLOCK(ump);
475 	}
476 	return (ENOSPC);
477 }
478 
479 /*
480  * Reallocate a sequence of blocks into a contiguous sequence of blocks.
481  *
482  * The vnode and an array of buffer pointers for a range of sequential
483  * logical blocks to be made contiguous is given. The allocator attempts
484  * to find a range of sequential blocks starting as close as possible
485  * from the end of the allocation for the logical block immediately
486  * preceding the current range. If successful, the physical block numbers
487  * in the buffer pointers and in the inode are changed to reflect the new
488  * allocation. If unsuccessful, the allocation is left unchanged. The
489  * success in doing the reallocation is returned. Note that the error
490  * return is not reflected back to the user. Rather the previous block
491  * allocation will be used.
492  */
493 
494 SYSCTL_NODE(_vfs, OID_AUTO, ffs, CTLFLAG_RW | CTLFLAG_MPSAFE, 0,
495     "FFS filesystem");
496 
497 static int doasyncfree = 1;
498 SYSCTL_INT(_vfs_ffs, OID_AUTO, doasyncfree, CTLFLAG_RW, &doasyncfree, 0,
499 "do not force synchronous writes when blocks are reallocated");
500 
501 static int doreallocblks = 1;
502 SYSCTL_INT(_vfs_ffs, OID_AUTO, doreallocblks, CTLFLAG_RW, &doreallocblks, 0,
503 "enable block reallocation");
504 
505 static int dotrimcons = 1;
506 SYSCTL_INT(_vfs_ffs, OID_AUTO, dotrimcons, CTLFLAG_RWTUN, &dotrimcons, 0,
507 "enable BIO_DELETE / TRIM consolidation");
508 
509 static int maxclustersearch = 10;
510 SYSCTL_INT(_vfs_ffs, OID_AUTO, maxclustersearch, CTLFLAG_RW, &maxclustersearch,
511 0, "max number of cylinder group to search for contigous blocks");
512 
513 #ifdef DIAGNOSTIC
514 static int prtrealloc = 0;
515 SYSCTL_INT(_debug, OID_AUTO, ffs_prtrealloc, CTLFLAG_RW, &prtrealloc, 0,
516 	"print out FFS filesystem block reallocation operations");
517 #endif
518 
519 int
520 ffs_reallocblks(
521 	struct vop_reallocblks_args /* {
522 		struct vnode *a_vp;
523 		struct cluster_save *a_buflist;
524 	} */ *ap)
525 {
526 	struct ufsmount *ump;
527 	int error;
528 
529 	/*
530 	 * We used to skip reallocating the blocks of a file into a
531 	 * contiguous sequence if the underlying flash device requested
532 	 * BIO_DELETE notifications, because devices that benefit from
533 	 * BIO_DELETE also benefit from not moving the data. However,
534 	 * the destination for the data is usually moved before the data
535 	 * is written to the initially allocated location, so we rarely
536 	 * suffer the penalty of extra writes. With the addition of the
537 	 * consolidation of contiguous blocks into single BIO_DELETE
538 	 * operations, having fewer but larger contiguous blocks reduces
539 	 * the number of (slow and expensive) BIO_DELETE operations. So
540 	 * when doing BIO_DELETE consolidation, we do block reallocation.
541 	 *
542 	 * Skip if reallocblks has been disabled globally.
543 	 */
544 	ump = ap->a_vp->v_mount->mnt_data;
545 	if ((((ump->um_flags) & UM_CANDELETE) != 0 && dotrimcons == 0) ||
546 	    doreallocblks == 0)
547 		return (ENOSPC);
548 
549 	/*
550 	 * We can't wait in softdep prealloc as it may fsync and recurse
551 	 * here.  Instead we simply fail to reallocate blocks if this
552 	 * rare condition arises.
553 	 */
554 	if (DOINGSUJ(ap->a_vp))
555 		if (softdep_prealloc(ap->a_vp, MNT_NOWAIT) != 0)
556 			return (ENOSPC);
557 	vn_seqc_write_begin(ap->a_vp);
558 	error = ump->um_fstype == UFS1 ? ffs_reallocblks_ufs1(ap) :
559 	    ffs_reallocblks_ufs2(ap);
560 	vn_seqc_write_end(ap->a_vp);
561 	return (error);
562 }
563 
564 static int
565 ffs_reallocblks_ufs1(
566 	struct vop_reallocblks_args /* {
567 		struct vnode *a_vp;
568 		struct cluster_save *a_buflist;
569 	} */ *ap)
570 {
571 	struct fs *fs;
572 	struct inode *ip;
573 	struct vnode *vp;
574 	struct buf *sbp, *ebp, *bp;
575 	ufs1_daddr_t *bap, *sbap, *ebap;
576 	struct cluster_save *buflist;
577 	struct ufsmount *ump;
578 	ufs_lbn_t start_lbn, end_lbn;
579 	ufs1_daddr_t soff, newblk, blkno;
580 	ufs2_daddr_t pref;
581 	struct indir start_ap[UFS_NIADDR + 1], end_ap[UFS_NIADDR + 1], *idp;
582 	int i, cg, len, start_lvl, end_lvl, ssize;
583 
584 	vp = ap->a_vp;
585 	ip = VTOI(vp);
586 	ump = ITOUMP(ip);
587 	fs = ump->um_fs;
588 	/*
589 	 * If we are not tracking block clusters or if we have less than 4%
590 	 * free blocks left, then do not attempt to cluster. Running with
591 	 * less than 5% free block reserve is not recommended and those that
592 	 * choose to do so do not expect to have good file layout.
593 	 */
594 	if (fs->fs_contigsumsize <= 0 || freespace(fs, 4) < 0)
595 		return (ENOSPC);
596 	buflist = ap->a_buflist;
597 	len = buflist->bs_nchildren;
598 	start_lbn = buflist->bs_children[0]->b_lblkno;
599 	end_lbn = start_lbn + len - 1;
600 #ifdef INVARIANTS
601 	for (i = 0; i < len; i++)
602 		if (!ffs_checkfreeblk(ip,
603 		   dbtofsb(fs, buflist->bs_children[i]->b_blkno), fs->fs_bsize))
604 			panic("ffs_reallocblks: unallocated block 1");
605 	for (i = 1; i < len; i++)
606 		if (buflist->bs_children[i]->b_lblkno != start_lbn + i)
607 			panic("ffs_reallocblks: non-logical cluster");
608 	blkno = buflist->bs_children[0]->b_blkno;
609 	ssize = fsbtodb(fs, fs->fs_frag);
610 	for (i = 1; i < len - 1; i++)
611 		if (buflist->bs_children[i]->b_blkno != blkno + (i * ssize))
612 			panic("ffs_reallocblks: non-physical cluster %d", i);
613 #endif
614 	/*
615 	 * If the cluster crosses the boundary for the first indirect
616 	 * block, leave space for the indirect block. Indirect blocks
617 	 * are initially laid out in a position after the last direct
618 	 * block. Block reallocation would usually destroy locality by
619 	 * moving the indirect block out of the way to make room for
620 	 * data blocks if we didn't compensate here. We should also do
621 	 * this for other indirect block boundaries, but it is only
622 	 * important for the first one.
623 	 */
624 	if (start_lbn < UFS_NDADDR && end_lbn >= UFS_NDADDR)
625 		return (ENOSPC);
626 	/*
627 	 * If the latest allocation is in a new cylinder group, assume that
628 	 * the filesystem has decided to move and do not force it back to
629 	 * the previous cylinder group.
630 	 */
631 	if (dtog(fs, dbtofsb(fs, buflist->bs_children[0]->b_blkno)) !=
632 	    dtog(fs, dbtofsb(fs, buflist->bs_children[len - 1]->b_blkno)))
633 		return (ENOSPC);
634 	if (ufs_getlbns(vp, start_lbn, start_ap, &start_lvl) ||
635 	    ufs_getlbns(vp, end_lbn, end_ap, &end_lvl))
636 		return (ENOSPC);
637 	/*
638 	 * Get the starting offset and block map for the first block.
639 	 */
640 	if (start_lvl == 0) {
641 		sbap = &ip->i_din1->di_db[0];
642 		soff = start_lbn;
643 	} else {
644 		idp = &start_ap[start_lvl - 1];
645 		if (bread(vp, idp->in_lbn, (int)fs->fs_bsize, NOCRED, &sbp)) {
646 			brelse(sbp);
647 			return (ENOSPC);
648 		}
649 		sbap = (ufs1_daddr_t *)sbp->b_data;
650 		soff = idp->in_off;
651 	}
652 	/*
653 	 * If the block range spans two block maps, get the second map.
654 	 */
655 	ebap = NULL;
656 	if (end_lvl == 0 || (idp = &end_ap[end_lvl - 1])->in_off + 1 >= len) {
657 		ssize = len;
658 	} else {
659 #ifdef INVARIANTS
660 		if (start_lvl > 0 &&
661 		    start_ap[start_lvl - 1].in_lbn == idp->in_lbn)
662 			panic("ffs_reallocblk: start == end");
663 #endif
664 		ssize = len - (idp->in_off + 1);
665 		if (bread(vp, idp->in_lbn, (int)fs->fs_bsize, NOCRED, &ebp))
666 			goto fail;
667 		ebap = (ufs1_daddr_t *)ebp->b_data;
668 	}
669 	/*
670 	 * Find the preferred location for the cluster. If we have not
671 	 * previously failed at this endeavor, then follow our standard
672 	 * preference calculation. If we have failed at it, then pick up
673 	 * where we last ended our search.
674 	 */
675 	UFS_LOCK(ump);
676 	if (ip->i_nextclustercg == -1)
677 		pref = ffs_blkpref_ufs1(ip, start_lbn, soff, sbap);
678 	else
679 		pref = cgdata(fs, ip->i_nextclustercg);
680 	/*
681 	 * Search the block map looking for an allocation of the desired size.
682 	 * To avoid wasting too much time, we limit the number of cylinder
683 	 * groups that we will search.
684 	 */
685 	cg = dtog(fs, pref);
686 	for (i = min(maxclustersearch, fs->fs_ncg); i > 0; i--) {
687 		if ((newblk = ffs_clusteralloc(ip, cg, pref, len)) != 0)
688 			break;
689 		cg += 1;
690 		if (cg >= fs->fs_ncg)
691 			cg = 0;
692 	}
693 	/*
694 	 * If we have failed in our search, record where we gave up for
695 	 * next time. Otherwise, fall back to our usual search citerion.
696 	 */
697 	if (newblk == 0) {
698 		ip->i_nextclustercg = cg;
699 		UFS_UNLOCK(ump);
700 		goto fail;
701 	}
702 	ip->i_nextclustercg = -1;
703 	/*
704 	 * We have found a new contiguous block.
705 	 *
706 	 * First we have to replace the old block pointers with the new
707 	 * block pointers in the inode and indirect blocks associated
708 	 * with the file.
709 	 */
710 #ifdef DIAGNOSTIC
711 	if (prtrealloc)
712 		printf("realloc: ino %ju, lbns %jd-%jd\n\told:",
713 		    (uintmax_t)ip->i_number,
714 		    (intmax_t)start_lbn, (intmax_t)end_lbn);
715 #endif
716 	blkno = newblk;
717 	for (bap = &sbap[soff], i = 0; i < len; i++, blkno += fs->fs_frag) {
718 		if (i == ssize) {
719 			bap = ebap;
720 			soff = -i;
721 		}
722 #ifdef INVARIANTS
723 		if (!ffs_checkfreeblk(ip,
724 		   dbtofsb(fs, buflist->bs_children[i]->b_blkno), fs->fs_bsize))
725 			panic("ffs_reallocblks: unallocated block 2");
726 		if (dbtofsb(fs, buflist->bs_children[i]->b_blkno) != *bap)
727 			panic("ffs_reallocblks: alloc mismatch");
728 #endif
729 #ifdef DIAGNOSTIC
730 		if (prtrealloc)
731 			printf(" %d,", *bap);
732 #endif
733 		if (DOINGSOFTDEP(vp)) {
734 			if (sbap == &ip->i_din1->di_db[0] && i < ssize)
735 				softdep_setup_allocdirect(ip, start_lbn + i,
736 				    blkno, *bap, fs->fs_bsize, fs->fs_bsize,
737 				    buflist->bs_children[i]);
738 			else
739 				softdep_setup_allocindir_page(ip, start_lbn + i,
740 				    i < ssize ? sbp : ebp, soff + i, blkno,
741 				    *bap, buflist->bs_children[i]);
742 		}
743 		*bap++ = blkno;
744 	}
745 	/*
746 	 * Next we must write out the modified inode and indirect blocks.
747 	 * For strict correctness, the writes should be synchronous since
748 	 * the old block values may have been written to disk. In practise
749 	 * they are almost never written, but if we are concerned about
750 	 * strict correctness, the `doasyncfree' flag should be set to zero.
751 	 *
752 	 * The test on `doasyncfree' should be changed to test a flag
753 	 * that shows whether the associated buffers and inodes have
754 	 * been written. The flag should be set when the cluster is
755 	 * started and cleared whenever the buffer or inode is flushed.
756 	 * We can then check below to see if it is set, and do the
757 	 * synchronous write only when it has been cleared.
758 	 */
759 	if (sbap != &ip->i_din1->di_db[0]) {
760 		if (doasyncfree)
761 			bdwrite(sbp);
762 		else
763 			bwrite(sbp);
764 	} else {
765 		UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_UPDATE);
766 		if (!doasyncfree)
767 			ffs_update(vp, 1);
768 	}
769 	if (ssize < len) {
770 		if (doasyncfree)
771 			bdwrite(ebp);
772 		else
773 			bwrite(ebp);
774 	}
775 	/*
776 	 * Last, free the old blocks and assign the new blocks to the buffers.
777 	 */
778 #ifdef DIAGNOSTIC
779 	if (prtrealloc)
780 		printf("\n\tnew:");
781 #endif
782 	for (blkno = newblk, i = 0; i < len; i++, blkno += fs->fs_frag) {
783 		bp = buflist->bs_children[i];
784 		if (!DOINGSOFTDEP(vp))
785 			/*
786 			 * The usual case is that a set of N-contiguous blocks
787 			 * that was just allocated has been replaced with a
788 			 * set of N+1-contiguous blocks. If they are marked as
789 			 * B_DELWRI, the current contents have not been written
790 			 * to disk. It is possible that the blocks were written
791 			 * earlier, but very uncommon. If the blocks have never
792 			 * been written, there is no need to send a BIO_DELETE
793 			 * for them when they are freed. The gain from avoiding
794 			 * the TRIMs for the common case of unwritten blocks
795 			 * far exceeds the cost of the write amplification for
796 			 * the uncommon case of failing to send a TRIM for the
797 			 * blocks that had been written.
798 			 */
799 			ffs_blkfree(ump, fs, ump->um_devvp,
800 			    dbtofsb(fs, bp->b_blkno),
801 			    fs->fs_bsize, ip->i_number, vp->v_type, NULL,
802 			    (bp->b_flags & B_DELWRI) != 0 ?
803 			    NOTRIM_KEY : SINGLETON_KEY);
804 		bp->b_blkno = fsbtodb(fs, blkno);
805 #ifdef INVARIANTS
806 		if (!ffs_checkfreeblk(ip, dbtofsb(fs, bp->b_blkno),
807 		    fs->fs_bsize))
808 			panic("ffs_reallocblks: unallocated block 3");
809 #endif
810 #ifdef DIAGNOSTIC
811 		if (prtrealloc)
812 			printf(" %d,", blkno);
813 #endif
814 	}
815 #ifdef DIAGNOSTIC
816 	if (prtrealloc) {
817 		prtrealloc--;
818 		printf("\n");
819 	}
820 #endif
821 	return (0);
822 
823 fail:
824 	if (ssize < len)
825 		brelse(ebp);
826 	if (sbap != &ip->i_din1->di_db[0])
827 		brelse(sbp);
828 	return (ENOSPC);
829 }
830 
831 static int
832 ffs_reallocblks_ufs2(
833 	struct vop_reallocblks_args /* {
834 		struct vnode *a_vp;
835 		struct cluster_save *a_buflist;
836 	} */ *ap)
837 {
838 	struct fs *fs;
839 	struct inode *ip;
840 	struct vnode *vp;
841 	struct buf *sbp, *ebp, *bp;
842 	ufs2_daddr_t *bap, *sbap, *ebap;
843 	struct cluster_save *buflist;
844 	struct ufsmount *ump;
845 	ufs_lbn_t start_lbn, end_lbn;
846 	ufs2_daddr_t soff, newblk, blkno, pref;
847 	struct indir start_ap[UFS_NIADDR + 1], end_ap[UFS_NIADDR + 1], *idp;
848 	int i, cg, len, start_lvl, end_lvl, ssize;
849 
850 	vp = ap->a_vp;
851 	ip = VTOI(vp);
852 	ump = ITOUMP(ip);
853 	fs = ump->um_fs;
854 	/*
855 	 * If we are not tracking block clusters or if we have less than 4%
856 	 * free blocks left, then do not attempt to cluster. Running with
857 	 * less than 5% free block reserve is not recommended and those that
858 	 * choose to do so do not expect to have good file layout.
859 	 */
860 	if (fs->fs_contigsumsize <= 0 || freespace(fs, 4) < 0)
861 		return (ENOSPC);
862 	buflist = ap->a_buflist;
863 	len = buflist->bs_nchildren;
864 	start_lbn = buflist->bs_children[0]->b_lblkno;
865 	end_lbn = start_lbn + len - 1;
866 #ifdef INVARIANTS
867 	for (i = 0; i < len; i++)
868 		if (!ffs_checkfreeblk(ip,
869 		   dbtofsb(fs, buflist->bs_children[i]->b_blkno), fs->fs_bsize))
870 			panic("ffs_reallocblks: unallocated block 1");
871 	for (i = 1; i < len; i++)
872 		if (buflist->bs_children[i]->b_lblkno != start_lbn + i)
873 			panic("ffs_reallocblks: non-logical cluster");
874 	blkno = buflist->bs_children[0]->b_blkno;
875 	ssize = fsbtodb(fs, fs->fs_frag);
876 	for (i = 1; i < len - 1; i++)
877 		if (buflist->bs_children[i]->b_blkno != blkno + (i * ssize))
878 			panic("ffs_reallocblks: non-physical cluster %d", i);
879 #endif
880 	/*
881 	 * If the cluster crosses the boundary for the first indirect
882 	 * block, do not move anything in it. Indirect blocks are
883 	 * usually initially laid out in a position between the data
884 	 * blocks. Block reallocation would usually destroy locality by
885 	 * moving the indirect block out of the way to make room for
886 	 * data blocks if we didn't compensate here. We should also do
887 	 * this for other indirect block boundaries, but it is only
888 	 * important for the first one.
889 	 */
890 	if (start_lbn < UFS_NDADDR && end_lbn >= UFS_NDADDR)
891 		return (ENOSPC);
892 	/*
893 	 * If the latest allocation is in a new cylinder group, assume that
894 	 * the filesystem has decided to move and do not force it back to
895 	 * the previous cylinder group.
896 	 */
897 	if (dtog(fs, dbtofsb(fs, buflist->bs_children[0]->b_blkno)) !=
898 	    dtog(fs, dbtofsb(fs, buflist->bs_children[len - 1]->b_blkno)))
899 		return (ENOSPC);
900 	if (ufs_getlbns(vp, start_lbn, start_ap, &start_lvl) ||
901 	    ufs_getlbns(vp, end_lbn, end_ap, &end_lvl))
902 		return (ENOSPC);
903 	/*
904 	 * Get the starting offset and block map for the first block.
905 	 */
906 	if (start_lvl == 0) {
907 		sbap = &ip->i_din2->di_db[0];
908 		soff = start_lbn;
909 	} else {
910 		idp = &start_ap[start_lvl - 1];
911 		if (bread(vp, idp->in_lbn, (int)fs->fs_bsize, NOCRED, &sbp)) {
912 			brelse(sbp);
913 			return (ENOSPC);
914 		}
915 		sbap = (ufs2_daddr_t *)sbp->b_data;
916 		soff = idp->in_off;
917 	}
918 	/*
919 	 * If the block range spans two block maps, get the second map.
920 	 */
921 	ebap = NULL;
922 	if (end_lvl == 0 || (idp = &end_ap[end_lvl - 1])->in_off + 1 >= len) {
923 		ssize = len;
924 	} else {
925 #ifdef INVARIANTS
926 		if (start_lvl > 0 &&
927 		    start_ap[start_lvl - 1].in_lbn == idp->in_lbn)
928 			panic("ffs_reallocblk: start == end");
929 #endif
930 		ssize = len - (idp->in_off + 1);
931 		if (bread(vp, idp->in_lbn, (int)fs->fs_bsize, NOCRED, &ebp))
932 			goto fail;
933 		ebap = (ufs2_daddr_t *)ebp->b_data;
934 	}
935 	/*
936 	 * Find the preferred location for the cluster. If we have not
937 	 * previously failed at this endeavor, then follow our standard
938 	 * preference calculation. If we have failed at it, then pick up
939 	 * where we last ended our search.
940 	 */
941 	UFS_LOCK(ump);
942 	if (ip->i_nextclustercg == -1)
943 		pref = ffs_blkpref_ufs2(ip, start_lbn, soff, sbap);
944 	else
945 		pref = cgdata(fs, ip->i_nextclustercg);
946 	/*
947 	 * Search the block map looking for an allocation of the desired size.
948 	 * To avoid wasting too much time, we limit the number of cylinder
949 	 * groups that we will search.
950 	 */
951 	cg = dtog(fs, pref);
952 	for (i = min(maxclustersearch, fs->fs_ncg); i > 0; i--) {
953 		if ((newblk = ffs_clusteralloc(ip, cg, pref, len)) != 0)
954 			break;
955 		cg += 1;
956 		if (cg >= fs->fs_ncg)
957 			cg = 0;
958 	}
959 	/*
960 	 * If we have failed in our search, record where we gave up for
961 	 * next time. Otherwise, fall back to our usual search citerion.
962 	 */
963 	if (newblk == 0) {
964 		ip->i_nextclustercg = cg;
965 		UFS_UNLOCK(ump);
966 		goto fail;
967 	}
968 	ip->i_nextclustercg = -1;
969 	/*
970 	 * We have found a new contiguous block.
971 	 *
972 	 * First we have to replace the old block pointers with the new
973 	 * block pointers in the inode and indirect blocks associated
974 	 * with the file.
975 	 */
976 #ifdef DIAGNOSTIC
977 	if (prtrealloc)
978 		printf("realloc: ino %ju, lbns %jd-%jd\n\told:", (uintmax_t)ip->i_number,
979 		    (intmax_t)start_lbn, (intmax_t)end_lbn);
980 #endif
981 	blkno = newblk;
982 	for (bap = &sbap[soff], i = 0; i < len; i++, blkno += fs->fs_frag) {
983 		if (i == ssize) {
984 			bap = ebap;
985 			soff = -i;
986 		}
987 #ifdef INVARIANTS
988 		if (!ffs_checkfreeblk(ip,
989 		   dbtofsb(fs, buflist->bs_children[i]->b_blkno), fs->fs_bsize))
990 			panic("ffs_reallocblks: unallocated block 2");
991 		if (dbtofsb(fs, buflist->bs_children[i]->b_blkno) != *bap)
992 			panic("ffs_reallocblks: alloc mismatch");
993 #endif
994 #ifdef DIAGNOSTIC
995 		if (prtrealloc)
996 			printf(" %jd,", (intmax_t)*bap);
997 #endif
998 		if (DOINGSOFTDEP(vp)) {
999 			if (sbap == &ip->i_din2->di_db[0] && i < ssize)
1000 				softdep_setup_allocdirect(ip, start_lbn + i,
1001 				    blkno, *bap, fs->fs_bsize, fs->fs_bsize,
1002 				    buflist->bs_children[i]);
1003 			else
1004 				softdep_setup_allocindir_page(ip, start_lbn + i,
1005 				    i < ssize ? sbp : ebp, soff + i, blkno,
1006 				    *bap, buflist->bs_children[i]);
1007 		}
1008 		*bap++ = blkno;
1009 	}
1010 	/*
1011 	 * Next we must write out the modified inode and indirect blocks.
1012 	 * For strict correctness, the writes should be synchronous since
1013 	 * the old block values may have been written to disk. In practise
1014 	 * they are almost never written, but if we are concerned about
1015 	 * strict correctness, the `doasyncfree' flag should be set to zero.
1016 	 *
1017 	 * The test on `doasyncfree' should be changed to test a flag
1018 	 * that shows whether the associated buffers and inodes have
1019 	 * been written. The flag should be set when the cluster is
1020 	 * started and cleared whenever the buffer or inode is flushed.
1021 	 * We can then check below to see if it is set, and do the
1022 	 * synchronous write only when it has been cleared.
1023 	 */
1024 	if (sbap != &ip->i_din2->di_db[0]) {
1025 		if (doasyncfree)
1026 			bdwrite(sbp);
1027 		else
1028 			bwrite(sbp);
1029 	} else {
1030 		UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_UPDATE);
1031 		if (!doasyncfree)
1032 			ffs_update(vp, 1);
1033 	}
1034 	if (ssize < len) {
1035 		if (doasyncfree)
1036 			bdwrite(ebp);
1037 		else
1038 			bwrite(ebp);
1039 	}
1040 	/*
1041 	 * Last, free the old blocks and assign the new blocks to the buffers.
1042 	 */
1043 #ifdef DIAGNOSTIC
1044 	if (prtrealloc)
1045 		printf("\n\tnew:");
1046 #endif
1047 	for (blkno = newblk, i = 0; i < len; i++, blkno += fs->fs_frag) {
1048 		bp = buflist->bs_children[i];
1049 		if (!DOINGSOFTDEP(vp))
1050 			/*
1051 			 * The usual case is that a set of N-contiguous blocks
1052 			 * that was just allocated has been replaced with a
1053 			 * set of N+1-contiguous blocks. If they are marked as
1054 			 * B_DELWRI, the current contents have not been written
1055 			 * to disk. It is possible that the blocks were written
1056 			 * earlier, but very uncommon. If the blocks have never
1057 			 * been written, there is no need to send a BIO_DELETE
1058 			 * for them when they are freed. The gain from avoiding
1059 			 * the TRIMs for the common case of unwritten blocks
1060 			 * far exceeds the cost of the write amplification for
1061 			 * the uncommon case of failing to send a TRIM for the
1062 			 * blocks that had been written.
1063 			 */
1064 			ffs_blkfree(ump, fs, ump->um_devvp,
1065 			    dbtofsb(fs, bp->b_blkno),
1066 			    fs->fs_bsize, ip->i_number, vp->v_type, NULL,
1067 			    (bp->b_flags & B_DELWRI) != 0 ?
1068 			    NOTRIM_KEY : SINGLETON_KEY);
1069 		bp->b_blkno = fsbtodb(fs, blkno);
1070 #ifdef INVARIANTS
1071 		if (!ffs_checkfreeblk(ip, dbtofsb(fs, bp->b_blkno),
1072 		    fs->fs_bsize))
1073 			panic("ffs_reallocblks: unallocated block 3");
1074 #endif
1075 #ifdef DIAGNOSTIC
1076 		if (prtrealloc)
1077 			printf(" %jd,", (intmax_t)blkno);
1078 #endif
1079 	}
1080 #ifdef DIAGNOSTIC
1081 	if (prtrealloc) {
1082 		prtrealloc--;
1083 		printf("\n");
1084 	}
1085 #endif
1086 	return (0);
1087 
1088 fail:
1089 	if (ssize < len)
1090 		brelse(ebp);
1091 	if (sbap != &ip->i_din2->di_db[0])
1092 		brelse(sbp);
1093 	return (ENOSPC);
1094 }
1095 
1096 /*
1097  * Allocate an inode in the filesystem.
1098  *
1099  * If allocating a directory, use ffs_dirpref to select the inode.
1100  * If allocating in a directory, the following hierarchy is followed:
1101  *   1) allocate the preferred inode.
1102  *   2) allocate an inode in the same cylinder group.
1103  *   3) quadratically rehash into other cylinder groups, until an
1104  *      available inode is located.
1105  * If no inode preference is given the following hierarchy is used
1106  * to allocate an inode:
1107  *   1) allocate an inode in cylinder group 0.
1108  *   2) quadratically rehash into other cylinder groups, until an
1109  *      available inode is located.
1110  */
1111 int
1112 ffs_valloc(struct vnode *pvp,
1113 	int mode,
1114 	struct ucred *cred,
1115 	struct vnode **vpp)
1116 {
1117 	struct inode *pip;
1118 	struct fs *fs;
1119 	struct inode *ip;
1120 	struct timespec ts;
1121 	struct ufsmount *ump;
1122 	ino_t ino, ipref;
1123 	uint64_t cg;
1124 	int error, reclaimed;
1125 
1126 	*vpp = NULL;
1127 	pip = VTOI(pvp);
1128 	ump = ITOUMP(pip);
1129 	fs = ump->um_fs;
1130 
1131 	UFS_LOCK(ump);
1132 	reclaimed = 0;
1133 retry:
1134 	if (fs->fs_cstotal.cs_nifree == 0)
1135 		goto noinodes;
1136 
1137 	if ((mode & IFMT) == IFDIR)
1138 		ipref = ffs_dirpref(pip);
1139 	else
1140 		ipref = pip->i_number;
1141 	if (ipref >= fs->fs_ncg * fs->fs_ipg)
1142 		ipref = 0;
1143 	cg = ino_to_cg(fs, ipref);
1144 	/*
1145 	 * Track number of dirs created one after another
1146 	 * in a same cg without intervening by files.
1147 	 */
1148 	if ((mode & IFMT) == IFDIR) {
1149 		if (fs->fs_contigdirs[cg] < 255)
1150 			fs->fs_contigdirs[cg]++;
1151 	} else {
1152 		if (fs->fs_contigdirs[cg] > 0)
1153 			fs->fs_contigdirs[cg]--;
1154 	}
1155 	ino = (ino_t)ffs_hashalloc(pip, cg, ipref, mode, 0,
1156 					(allocfcn_t *)ffs_nodealloccg);
1157 	if (ino == 0)
1158 		goto noinodes;
1159 	/*
1160 	 * Get rid of the cached old vnode, force allocation of a new vnode
1161 	 * for this inode. If this fails, release the allocated ino and
1162 	 * return the error.
1163 	 */
1164 	if ((error = ffs_vgetf(pvp->v_mount, ino, LK_EXCLUSIVE, vpp,
1165 	    FFSV_FORCEINSMQ | FFSV_REPLACE | FFSV_NEWINODE)) != 0) {
1166 		ffs_vfree(pvp, ino, mode);
1167 		return (error);
1168 	}
1169 	/*
1170 	 * We got an inode, so check mode and panic if it is already allocated.
1171 	 */
1172 	ip = VTOI(*vpp);
1173 	if (ip->i_mode) {
1174 		printf("mode = 0%o, inum = %ju, fs = %s\n",
1175 		    ip->i_mode, (uintmax_t)ip->i_number, fs->fs_fsmnt);
1176 		panic("ffs_valloc: dup alloc");
1177 	}
1178 	if (DIP(ip, i_blocks) && (fs->fs_flags & FS_UNCLEAN) == 0) {  /* XXX */
1179 		printf("free inode %s/%ju had %ld blocks\n",
1180 		    fs->fs_fsmnt, (intmax_t)ino, (long)DIP(ip, i_blocks));
1181 		DIP_SET(ip, i_blocks, 0);
1182 	}
1183 	ip->i_flags = 0;
1184 	DIP_SET(ip, i_flags, 0);
1185 	if ((mode & IFMT) == IFDIR)
1186 		DIP_SET(ip, i_dirdepth, DIP(pip, i_dirdepth) + 1);
1187 	/*
1188 	 * Set up a new generation number for this inode.
1189 	 */
1190 	while (ip->i_gen == 0 || ++ip->i_gen == 0)
1191 		ip->i_gen = arc4random();
1192 	DIP_SET(ip, i_gen, ip->i_gen);
1193 	if (fs->fs_magic == FS_UFS2_MAGIC) {
1194 		vfs_timestamp(&ts);
1195 		ip->i_din2->di_birthtime = ts.tv_sec;
1196 		ip->i_din2->di_birthnsec = ts.tv_nsec;
1197 	}
1198 	ip->i_flag = 0;
1199 	(*vpp)->v_vflag = 0;
1200 	(*vpp)->v_type = VNON;
1201 	if (fs->fs_magic == FS_UFS2_MAGIC) {
1202 		(*vpp)->v_op = &ffs_vnodeops2;
1203 		UFS_INODE_SET_FLAG(ip, IN_UFS2);
1204 	} else {
1205 		(*vpp)->v_op = &ffs_vnodeops1;
1206 	}
1207 	return (0);
1208 noinodes:
1209 	if (reclaimed == 0) {
1210 		reclaimed = 1;
1211 		softdep_request_cleanup(fs, pvp, cred, FLUSH_INODES_WAIT);
1212 		goto retry;
1213 	}
1214 	if (ffs_fsfail_cleanup_locked(ump, 0)) {
1215 		UFS_UNLOCK(ump);
1216 		return (ENXIO);
1217 	}
1218 	if (ppsratecheck(&ump->um_last_fullmsg, &ump->um_secs_fullmsg, 1)) {
1219 		UFS_UNLOCK(ump);
1220 		ffs_fserr(fs, pip->i_number, "out of inodes");
1221 		uprintf("\n%s: create/symlink failed, no inodes free\n",
1222 		    fs->fs_fsmnt);
1223 	} else {
1224 		UFS_UNLOCK(ump);
1225 	}
1226 	return (ENOSPC);
1227 }
1228 
1229 /*
1230  * Find a cylinder group to place a directory.
1231  *
1232  * The policy implemented by this algorithm is to allocate a
1233  * directory inode in the same cylinder group as its parent
1234  * directory, but also to reserve space for its files inodes
1235  * and data. Restrict the number of directories which may be
1236  * allocated one after another in the same cylinder group
1237  * without intervening allocation of files.
1238  *
1239  * If we allocate a first level directory then force allocation
1240  * in another cylinder group.
1241  */
1242 static ino_t
1243 ffs_dirpref(struct inode *pip)
1244 {
1245 	struct fs *fs;
1246 	int cg, prefcg, curcg, dirsize, cgsize;
1247 	int depth, range, start, end, numdirs, power, numerator, denominator;
1248 	uint64_t avgifree, avgbfree, avgndir, curdirsize;
1249 	uint64_t minifree, minbfree, maxndir;
1250 	uint64_t maxcontigdirs;
1251 
1252 	mtx_assert(UFS_MTX(ITOUMP(pip)), MA_OWNED);
1253 	fs = ITOFS(pip);
1254 
1255 	avgifree = fs->fs_cstotal.cs_nifree / fs->fs_ncg;
1256 	avgbfree = fs->fs_cstotal.cs_nbfree / fs->fs_ncg;
1257 	avgndir = fs->fs_cstotal.cs_ndir / fs->fs_ncg;
1258 
1259 	/*
1260 	 * Select a preferred cylinder group to place a new directory.
1261 	 * If we are near the root of the filesystem we aim to spread
1262 	 * them out as much as possible. As we descend deeper from the
1263 	 * root we cluster them closer together around their parent as
1264 	 * we expect them to be more closely interactive. Higher-level
1265 	 * directories like usr/src/sys and usr/src/bin should be
1266 	 * separated while the directories in these areas are more
1267 	 * likely to be accessed together so should be closer.
1268 	 *
1269 	 * We pick a range of cylinder groups around the cylinder group
1270 	 * of the directory in which we are being created. The size of
1271 	 * the range for our search is based on our depth from the root
1272 	 * of our filesystem. We then probe that range based on how many
1273 	 * directories are already present. The first new directory is at
1274 	 * 1/2 (middle) of the range; the second is in the first 1/4 of the
1275 	 * range, then at 3/4, 1/8, 3/8, 5/8, 7/8, 1/16, 3/16, 5/16, etc.
1276 	 */
1277 	depth = DIP(pip, i_dirdepth);
1278 	range = fs->fs_ncg / (1 << depth);
1279 	curcg = ino_to_cg(fs, pip->i_number);
1280 	start = curcg - (range / 2);
1281 	if (start < 0)
1282 		start += fs->fs_ncg;
1283 	end = curcg + (range / 2);
1284 	if (end >= fs->fs_ncg)
1285 		end -= fs->fs_ncg;
1286 	numdirs = pip->i_effnlink - 1;
1287 	power = fls(numdirs);
1288 	numerator = (numdirs & ~(1 << (power - 1))) * 2 + 1;
1289 	denominator = 1 << power;
1290 	prefcg = (curcg - (range / 2) + (range * numerator / denominator));
1291 	if (prefcg < 0)
1292 		prefcg += fs->fs_ncg;
1293 	if (prefcg >= fs->fs_ncg)
1294 		prefcg -= fs->fs_ncg;
1295 	/*
1296 	 * If this filesystem is not tracking directory depths,
1297 	 * revert to the old algorithm.
1298 	 */
1299 	if (depth == 0 && pip->i_number != UFS_ROOTINO)
1300 		prefcg = curcg;
1301 
1302 	/*
1303 	 * Count various limits which used for
1304 	 * optimal allocation of a directory inode.
1305 	 */
1306 	maxndir = min(avgndir + (1 << depth), fs->fs_ipg);
1307 	minifree = avgifree - avgifree / 4;
1308 	if (minifree < 1)
1309 		minifree = 1;
1310 	minbfree = avgbfree - avgbfree / 4;
1311 	if (minbfree < 1)
1312 		minbfree = 1;
1313 	cgsize = fs->fs_fsize * fs->fs_fpg;
1314 	dirsize = fs->fs_avgfilesize * fs->fs_avgfpdir;
1315 	curdirsize = avgndir ? (cgsize - avgbfree * fs->fs_bsize) / avgndir : 0;
1316 	if (dirsize < curdirsize)
1317 		dirsize = curdirsize;
1318 	if (dirsize <= 0)
1319 		maxcontigdirs = 0;		/* dirsize overflowed */
1320 	else
1321 		maxcontigdirs = min((avgbfree * fs->fs_bsize) / dirsize, 255);
1322 	if (fs->fs_avgfpdir > 0)
1323 		maxcontigdirs = min(maxcontigdirs,
1324 				    fs->fs_ipg / fs->fs_avgfpdir);
1325 	if (maxcontigdirs == 0)
1326 		maxcontigdirs = 1;
1327 
1328 	/*
1329 	 * Limit number of dirs in one cg and reserve space for
1330 	 * regular files, but only if we have no deficit in
1331 	 * inodes or space.
1332 	 *
1333 	 * We are trying to find a suitable cylinder group nearby
1334 	 * our preferred cylinder group to place a new directory.
1335 	 * We scan from our preferred cylinder group forward looking
1336 	 * for a cylinder group that meets our criterion. If we get
1337 	 * to the final cylinder group and do not find anything,
1338 	 * we start scanning forwards from the beginning of the
1339 	 * filesystem. While it might seem sensible to start scanning
1340 	 * backwards or even to alternate looking forward and backward,
1341 	 * this approach fails badly when the filesystem is nearly full.
1342 	 * Specifically, we first search all the areas that have no space
1343 	 * and finally try the one preceding that. We repeat this on
1344 	 * every request and in the case of the final block end up
1345 	 * searching the entire filesystem. By jumping to the front
1346 	 * of the filesystem, our future forward searches always look
1347 	 * in new cylinder groups so finds every possible block after
1348 	 * one pass over the filesystem.
1349 	 */
1350 	for (cg = prefcg; cg < fs->fs_ncg; cg++)
1351 		if (fs->fs_cs(fs, cg).cs_ndir < maxndir &&
1352 		    fs->fs_cs(fs, cg).cs_nifree >= minifree &&
1353 		    fs->fs_cs(fs, cg).cs_nbfree >= minbfree) {
1354 			if (fs->fs_contigdirs[cg] < maxcontigdirs)
1355 				return ((ino_t)(fs->fs_ipg * cg));
1356 		}
1357 	for (cg = 0; cg < prefcg; cg++)
1358 		if (fs->fs_cs(fs, cg).cs_ndir < maxndir &&
1359 		    fs->fs_cs(fs, cg).cs_nifree >= minifree &&
1360 		    fs->fs_cs(fs, cg).cs_nbfree >= minbfree) {
1361 			if (fs->fs_contigdirs[cg] < maxcontigdirs)
1362 				return ((ino_t)(fs->fs_ipg * cg));
1363 		}
1364 	/*
1365 	 * This is a backstop when we have deficit in space.
1366 	 */
1367 	for (cg = prefcg; cg < fs->fs_ncg; cg++)
1368 		if (fs->fs_cs(fs, cg).cs_nifree >= avgifree)
1369 			return ((ino_t)(fs->fs_ipg * cg));
1370 	for (cg = 0; cg < prefcg; cg++)
1371 		if (fs->fs_cs(fs, cg).cs_nifree >= avgifree)
1372 			break;
1373 	return ((ino_t)(fs->fs_ipg * cg));
1374 }
1375 
1376 /*
1377  * Select the desired position for the next block in a file.  The file is
1378  * logically divided into sections. The first section is composed of the
1379  * direct blocks and the next fs_maxbpg blocks. Each additional section
1380  * contains fs_maxbpg blocks.
1381  *
1382  * If no blocks have been allocated in the first section, the policy is to
1383  * request a block in the same cylinder group as the inode that describes
1384  * the file. The first indirect is allocated immediately following the last
1385  * direct block and the data blocks for the first indirect immediately
1386  * follow it.
1387  *
1388  * If no blocks have been allocated in any other section, the indirect
1389  * block(s) are allocated in the same cylinder group as its inode in an
1390  * area reserved immediately following the inode blocks. The policy for
1391  * the data blocks is to place them in a cylinder group with a greater than
1392  * average number of free blocks. An appropriate cylinder group is found
1393  * by using a rotor that sweeps the cylinder groups. When a new group of
1394  * blocks is needed, the sweep begins in the cylinder group following the
1395  * cylinder group from which the previous allocation was made. The sweep
1396  * continues until a cylinder group with greater than the average number
1397  * of free blocks is found. If the allocation is for the first block in an
1398  * indirect block or the previous block is a hole, then the information on
1399  * the previous allocation is unavailable; here a best guess is made based
1400  * on the logical block number being allocated.
1401  *
1402  * If a section is already partially allocated, the policy is to
1403  * allocate blocks contiguously within the section if possible.
1404  */
1405 ufs2_daddr_t
1406 ffs_blkpref_ufs1(struct inode *ip,
1407 	ufs_lbn_t lbn,
1408 	int indx,
1409 	ufs1_daddr_t *bap)
1410 {
1411 	struct fs *fs;
1412 	uint64_t cg, inocg;
1413 	uint64_t avgbfree, startcg;
1414 	ufs2_daddr_t pref, prevbn;
1415 
1416 	KASSERT(indx <= 0 || bap != NULL, ("need non-NULL bap"));
1417 	mtx_assert(UFS_MTX(ITOUMP(ip)), MA_OWNED);
1418 	fs = ITOFS(ip);
1419 	/*
1420 	 * Allocation of indirect blocks is indicated by passing negative
1421 	 * values in indx: -1 for single indirect, -2 for double indirect,
1422 	 * -3 for triple indirect. As noted below, we attempt to allocate
1423 	 * the first indirect inline with the file data. For all later
1424 	 * indirect blocks, the data is often allocated in other cylinder
1425 	 * groups. However to speed random file access and to speed up
1426 	 * fsck, the filesystem reserves the first fs_metaspace blocks
1427 	 * (typically half of fs_minfree) of the data area of each cylinder
1428 	 * group to hold these later indirect blocks.
1429 	 */
1430 	inocg = ino_to_cg(fs, ip->i_number);
1431 	if (indx < 0) {
1432 		/*
1433 		 * Our preference for indirect blocks is the zone at the
1434 		 * beginning of the inode's cylinder group data area that
1435 		 * we try to reserve for indirect blocks.
1436 		 */
1437 		pref = cgmeta(fs, inocg);
1438 		/*
1439 		 * If we are allocating the first indirect block, try to
1440 		 * place it immediately following the last direct block.
1441 		 */
1442 		if (indx == -1 && lbn < UFS_NDADDR + NINDIR(fs) &&
1443 		    ip->i_din1->di_db[UFS_NDADDR - 1] != 0)
1444 			pref = ip->i_din1->di_db[UFS_NDADDR - 1] + fs->fs_frag;
1445 		return (pref);
1446 	}
1447 	/*
1448 	 * If we are allocating the first data block in the first indirect
1449 	 * block and the indirect has been allocated in the data block area,
1450 	 * try to place it immediately following the indirect block.
1451 	 */
1452 	if (lbn == UFS_NDADDR) {
1453 		pref = ip->i_din1->di_ib[0];
1454 		if (pref != 0 && pref >= cgdata(fs, inocg) &&
1455 		    pref < cgbase(fs, inocg + 1))
1456 			return (pref + fs->fs_frag);
1457 	}
1458 	/*
1459 	 * If we are at the beginning of a file, or we have already allocated
1460 	 * the maximum number of blocks per cylinder group, or we do not
1461 	 * have a block allocated immediately preceding us, then we need
1462 	 * to decide where to start allocating new blocks.
1463 	 */
1464 	if (indx ==  0) {
1465 		prevbn = 0;
1466 	} else {
1467 		prevbn = bap[indx - 1];
1468 		if (UFS_CHECK_BLKNO(ITOVFS(ip), ip->i_number, prevbn,
1469 		    fs->fs_bsize) != 0)
1470 			prevbn = 0;
1471 	}
1472 	if (indx % fs->fs_maxbpg == 0 || prevbn == 0) {
1473 		/*
1474 		 * If we are allocating a directory data block, we want
1475 		 * to place it in the metadata area.
1476 		 */
1477 		if ((ip->i_mode & IFMT) == IFDIR)
1478 			return (cgmeta(fs, inocg));
1479 		/*
1480 		 * Until we fill all the direct and all the first indirect's
1481 		 * blocks, we try to allocate in the data area of the inode's
1482 		 * cylinder group.
1483 		 */
1484 		if (lbn < UFS_NDADDR + NINDIR(fs))
1485 			return (cgdata(fs, inocg));
1486 		/*
1487 		 * Find a cylinder with greater than average number of
1488 		 * unused data blocks.
1489 		 */
1490 		if (indx == 0 || prevbn == 0)
1491 			startcg = inocg + lbn / fs->fs_maxbpg;
1492 		else
1493 			startcg = dtog(fs, prevbn) + 1;
1494 		startcg %= fs->fs_ncg;
1495 		avgbfree = fs->fs_cstotal.cs_nbfree / fs->fs_ncg;
1496 		for (cg = startcg; cg < fs->fs_ncg; cg++)
1497 			if (fs->fs_cs(fs, cg).cs_nbfree >= avgbfree) {
1498 				fs->fs_cgrotor = cg;
1499 				return (cgdata(fs, cg));
1500 			}
1501 		for (cg = 0; cg <= startcg; cg++)
1502 			if (fs->fs_cs(fs, cg).cs_nbfree >= avgbfree) {
1503 				fs->fs_cgrotor = cg;
1504 				return (cgdata(fs, cg));
1505 			}
1506 		return (0);
1507 	}
1508 	/*
1509 	 * Otherwise, we just always try to lay things out contiguously.
1510 	 */
1511 	return (prevbn + fs->fs_frag);
1512 }
1513 
1514 /*
1515  * Same as above, but for UFS2
1516  */
1517 ufs2_daddr_t
1518 ffs_blkpref_ufs2(struct inode *ip,
1519 	ufs_lbn_t lbn,
1520 	int indx,
1521 	ufs2_daddr_t *bap)
1522 {
1523 	struct fs *fs;
1524 	uint64_t cg, inocg;
1525 	uint64_t avgbfree, startcg;
1526 	ufs2_daddr_t pref, prevbn;
1527 
1528 	KASSERT(indx <= 0 || bap != NULL, ("need non-NULL bap"));
1529 	mtx_assert(UFS_MTX(ITOUMP(ip)), MA_OWNED);
1530 	fs = ITOFS(ip);
1531 	/*
1532 	 * Allocation of indirect blocks is indicated by passing negative
1533 	 * values in indx: -1 for single indirect, -2 for double indirect,
1534 	 * -3 for triple indirect. As noted below, we attempt to allocate
1535 	 * the first indirect inline with the file data. For all later
1536 	 * indirect blocks, the data is often allocated in other cylinder
1537 	 * groups. However to speed random file access and to speed up
1538 	 * fsck, the filesystem reserves the first fs_metaspace blocks
1539 	 * (typically half of fs_minfree) of the data area of each cylinder
1540 	 * group to hold these later indirect blocks.
1541 	 */
1542 	inocg = ino_to_cg(fs, ip->i_number);
1543 	if (indx < 0) {
1544 		/*
1545 		 * Our preference for indirect blocks is the zone at the
1546 		 * beginning of the inode's cylinder group data area that
1547 		 * we try to reserve for indirect blocks.
1548 		 */
1549 		pref = cgmeta(fs, inocg);
1550 		/*
1551 		 * If we are allocating the first indirect block, try to
1552 		 * place it immediately following the last direct block.
1553 		 */
1554 		if (indx == -1 && lbn < UFS_NDADDR + NINDIR(fs) &&
1555 		    ip->i_din2->di_db[UFS_NDADDR - 1] != 0)
1556 			pref = ip->i_din2->di_db[UFS_NDADDR - 1] + fs->fs_frag;
1557 		return (pref);
1558 	}
1559 	/*
1560 	 * If we are allocating the first data block in the first indirect
1561 	 * block and the indirect has been allocated in the data block area,
1562 	 * try to place it immediately following the indirect block.
1563 	 */
1564 	if (lbn == UFS_NDADDR) {
1565 		pref = ip->i_din2->di_ib[0];
1566 		if (pref != 0 && pref >= cgdata(fs, inocg) &&
1567 		    pref < cgbase(fs, inocg + 1))
1568 			return (pref + fs->fs_frag);
1569 	}
1570 	/*
1571 	 * If we are at the beginning of a file, or we have already allocated
1572 	 * the maximum number of blocks per cylinder group, or we do not
1573 	 * have a block allocated immediately preceding us, then we need
1574 	 * to decide where to start allocating new blocks.
1575 	 */
1576 	if (indx ==  0) {
1577 		prevbn = 0;
1578 	} else {
1579 		prevbn = bap[indx - 1];
1580 		if (UFS_CHECK_BLKNO(ITOVFS(ip), ip->i_number, prevbn,
1581 		    fs->fs_bsize) != 0)
1582 			prevbn = 0;
1583 	}
1584 	if (indx % fs->fs_maxbpg == 0 || prevbn == 0) {
1585 		/*
1586 		 * If we are allocating a directory data block, we want
1587 		 * to place it in the metadata area.
1588 		 */
1589 		if ((ip->i_mode & IFMT) == IFDIR)
1590 			return (cgmeta(fs, inocg));
1591 		/*
1592 		 * Until we fill all the direct and all the first indirect's
1593 		 * blocks, we try to allocate in the data area of the inode's
1594 		 * cylinder group.
1595 		 */
1596 		if (lbn < UFS_NDADDR + NINDIR(fs))
1597 			return (cgdata(fs, inocg));
1598 		/*
1599 		 * Find a cylinder with greater than average number of
1600 		 * unused data blocks.
1601 		 */
1602 		if (indx == 0 || prevbn == 0)
1603 			startcg = inocg + lbn / fs->fs_maxbpg;
1604 		else
1605 			startcg = dtog(fs, prevbn) + 1;
1606 		startcg %= fs->fs_ncg;
1607 		avgbfree = fs->fs_cstotal.cs_nbfree / fs->fs_ncg;
1608 		for (cg = startcg; cg < fs->fs_ncg; cg++)
1609 			if (fs->fs_cs(fs, cg).cs_nbfree >= avgbfree) {
1610 				fs->fs_cgrotor = cg;
1611 				return (cgdata(fs, cg));
1612 			}
1613 		for (cg = 0; cg <= startcg; cg++)
1614 			if (fs->fs_cs(fs, cg).cs_nbfree >= avgbfree) {
1615 				fs->fs_cgrotor = cg;
1616 				return (cgdata(fs, cg));
1617 			}
1618 		return (0);
1619 	}
1620 	/*
1621 	 * Otherwise, we just always try to lay things out contiguously.
1622 	 */
1623 	return (prevbn + fs->fs_frag);
1624 }
1625 
1626 /*
1627  * Implement the cylinder overflow algorithm.
1628  *
1629  * The policy implemented by this algorithm is:
1630  *   1) allocate the block in its requested cylinder group.
1631  *   2) quadratically rehash on the cylinder group number.
1632  *   3) brute force search for a free block.
1633  *
1634  * Must be called with the UFS lock held.  Will release the lock on success
1635  * and return with it held on failure.
1636  */
1637 /*VARARGS5*/
1638 static ufs2_daddr_t
1639 ffs_hashalloc(struct inode *ip,
1640 	uint64_t cg,
1641 	ufs2_daddr_t pref,
1642 	int size,	/* Search size for data blocks, mode for inodes */
1643 	int rsize,	/* Real allocated size. */
1644 	allocfcn_t *allocator)
1645 {
1646 	struct fs *fs;
1647 	ufs2_daddr_t result;
1648 	uint64_t i, icg = cg;
1649 
1650 	mtx_assert(UFS_MTX(ITOUMP(ip)), MA_OWNED);
1651 #ifdef INVARIANTS
1652 	if (ITOV(ip)->v_mount->mnt_kern_flag & MNTK_SUSPENDED)
1653 		panic("ffs_hashalloc: allocation on suspended filesystem");
1654 #endif
1655 	fs = ITOFS(ip);
1656 	/*
1657 	 * 1: preferred cylinder group
1658 	 */
1659 	result = (*allocator)(ip, cg, pref, size, rsize);
1660 	if (result)
1661 		return (result);
1662 	/*
1663 	 * 2: quadratic rehash
1664 	 */
1665 	for (i = 1; i < fs->fs_ncg; i *= 2) {
1666 		cg += i;
1667 		if (cg >= fs->fs_ncg)
1668 			cg -= fs->fs_ncg;
1669 		result = (*allocator)(ip, cg, 0, size, rsize);
1670 		if (result)
1671 			return (result);
1672 	}
1673 	/*
1674 	 * 3: brute force search
1675 	 * Note that we start at i == 2, since 0 was checked initially,
1676 	 * and 1 is always checked in the quadratic rehash.
1677 	 */
1678 	cg = (icg + 2) % fs->fs_ncg;
1679 	for (i = 2; i < fs->fs_ncg; i++) {
1680 		result = (*allocator)(ip, cg, 0, size, rsize);
1681 		if (result)
1682 			return (result);
1683 		cg++;
1684 		if (cg == fs->fs_ncg)
1685 			cg = 0;
1686 	}
1687 	return (0);
1688 }
1689 
1690 /*
1691  * Determine whether a fragment can be extended.
1692  *
1693  * Check to see if the necessary fragments are available, and
1694  * if they are, allocate them.
1695  */
1696 static ufs2_daddr_t
1697 ffs_fragextend(struct inode *ip,
1698 	uint64_t cg,
1699 	ufs2_daddr_t bprev,
1700 	int osize,
1701 	int nsize)
1702 {
1703 	struct fs *fs;
1704 	struct cg *cgp;
1705 	struct buf *bp;
1706 	struct ufsmount *ump;
1707 	int nffree;
1708 	long bno;
1709 	int frags, bbase;
1710 	int i, error;
1711 	uint8_t *blksfree;
1712 
1713 	ump = ITOUMP(ip);
1714 	fs = ump->um_fs;
1715 	if (fs->fs_cs(fs, cg).cs_nffree < numfrags(fs, nsize - osize))
1716 		return (0);
1717 	frags = numfrags(fs, nsize);
1718 	bbase = fragnum(fs, bprev);
1719 	if (bbase > fragnum(fs, (bprev + frags - 1))) {
1720 		/* cannot extend across a block boundary */
1721 		return (0);
1722 	}
1723 	UFS_UNLOCK(ump);
1724 	if ((error = ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp)) != 0) {
1725 		ffs_checkcgintegrity(fs, cg, error);
1726 		goto fail;
1727 	}
1728 	bno = dtogd(fs, bprev);
1729 	blksfree = cg_blksfree(cgp);
1730 	for (i = numfrags(fs, osize); i < frags; i++)
1731 		if (isclr(blksfree, bno + i))
1732 			goto fail;
1733 	/*
1734 	 * the current fragment can be extended
1735 	 * deduct the count on fragment being extended into
1736 	 * increase the count on the remaining fragment (if any)
1737 	 * allocate the extended piece
1738 	 */
1739 	for (i = frags; i < fs->fs_frag - bbase; i++)
1740 		if (isclr(blksfree, bno + i))
1741 			break;
1742 	cgp->cg_frsum[i - numfrags(fs, osize)]--;
1743 	if (i != frags)
1744 		cgp->cg_frsum[i - frags]++;
1745 	for (i = numfrags(fs, osize), nffree = 0; i < frags; i++) {
1746 		clrbit(blksfree, bno + i);
1747 		cgp->cg_cs.cs_nffree--;
1748 		nffree++;
1749 	}
1750 	UFS_LOCK(ump);
1751 	fs->fs_cstotal.cs_nffree -= nffree;
1752 	fs->fs_cs(fs, cg).cs_nffree -= nffree;
1753 	fs->fs_fmod = 1;
1754 	ACTIVECLEAR(fs, cg);
1755 	UFS_UNLOCK(ump);
1756 	if (DOINGSOFTDEP(ITOV(ip)))
1757 		softdep_setup_blkmapdep(bp, UFSTOVFS(ump), bprev,
1758 		    frags, numfrags(fs, osize));
1759 	bdwrite(bp);
1760 	return (bprev);
1761 
1762 fail:
1763 	brelse(bp);
1764 	UFS_LOCK(ump);
1765 	return (0);
1766 
1767 }
1768 
1769 /*
1770  * Determine whether a block can be allocated.
1771  *
1772  * Check to see if a block of the appropriate size is available,
1773  * and if it is, allocate it.
1774  */
1775 static ufs2_daddr_t
1776 ffs_alloccg(struct inode *ip,
1777 	uint64_t cg,
1778 	ufs2_daddr_t bpref,
1779 	int size,
1780 	int rsize)
1781 {
1782 	struct fs *fs;
1783 	struct cg *cgp;
1784 	struct buf *bp;
1785 	struct ufsmount *ump;
1786 	ufs1_daddr_t bno;
1787 	ufs2_daddr_t blkno;
1788 	int i, allocsiz, error, frags;
1789 	uint8_t *blksfree;
1790 
1791 	ump = ITOUMP(ip);
1792 	fs = ump->um_fs;
1793 	if (fs->fs_cs(fs, cg).cs_nbfree == 0 && size == fs->fs_bsize)
1794 		return (0);
1795 	UFS_UNLOCK(ump);
1796 	if ((error = ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp)) != 0 ||
1797 	   (cgp->cg_cs.cs_nbfree == 0 && size == fs->fs_bsize)) {
1798 		ffs_checkcgintegrity(fs, cg, error);
1799 		goto fail;
1800 	}
1801 	if (size == fs->fs_bsize) {
1802 		UFS_LOCK(ump);
1803 		blkno = ffs_alloccgblk(ip, bp, bpref, rsize);
1804 		ACTIVECLEAR(fs, cg);
1805 		UFS_UNLOCK(ump);
1806 		bdwrite(bp);
1807 		return (blkno);
1808 	}
1809 	/*
1810 	 * check to see if any fragments are already available
1811 	 * allocsiz is the size which will be allocated, hacking
1812 	 * it down to a smaller size if necessary
1813 	 */
1814 	blksfree = cg_blksfree(cgp);
1815 	frags = numfrags(fs, size);
1816 	for (allocsiz = frags; allocsiz < fs->fs_frag; allocsiz++)
1817 		if (cgp->cg_frsum[allocsiz] != 0)
1818 			break;
1819 	if (allocsiz == fs->fs_frag) {
1820 		/*
1821 		 * no fragments were available, so a block will be
1822 		 * allocated, and hacked up
1823 		 */
1824 		if (cgp->cg_cs.cs_nbfree == 0)
1825 			goto fail;
1826 		UFS_LOCK(ump);
1827 		blkno = ffs_alloccgblk(ip, bp, bpref, rsize);
1828 		ACTIVECLEAR(fs, cg);
1829 		UFS_UNLOCK(ump);
1830 		bdwrite(bp);
1831 		return (blkno);
1832 	}
1833 	KASSERT(size == rsize,
1834 	    ("ffs_alloccg: size(%d) != rsize(%d)", size, rsize));
1835 	bno = ffs_mapsearch(fs, cgp, bpref, allocsiz);
1836 	if (bno < 0)
1837 		goto fail;
1838 	for (i = 0; i < frags; i++)
1839 		clrbit(blksfree, bno + i);
1840 	cgp->cg_cs.cs_nffree -= frags;
1841 	cgp->cg_frsum[allocsiz]--;
1842 	if (frags != allocsiz)
1843 		cgp->cg_frsum[allocsiz - frags]++;
1844 	UFS_LOCK(ump);
1845 	fs->fs_cstotal.cs_nffree -= frags;
1846 	fs->fs_cs(fs, cg).cs_nffree -= frags;
1847 	fs->fs_fmod = 1;
1848 	blkno = cgbase(fs, cg) + bno;
1849 	ACTIVECLEAR(fs, cg);
1850 	UFS_UNLOCK(ump);
1851 	if (DOINGSOFTDEP(ITOV(ip)))
1852 		softdep_setup_blkmapdep(bp, UFSTOVFS(ump), blkno, frags, 0);
1853 	bdwrite(bp);
1854 	return (blkno);
1855 
1856 fail:
1857 	brelse(bp);
1858 	UFS_LOCK(ump);
1859 	return (0);
1860 }
1861 
1862 /*
1863  * Allocate a block in a cylinder group.
1864  *
1865  * This algorithm implements the following policy:
1866  *   1) allocate the requested block.
1867  *   2) allocate a rotationally optimal block in the same cylinder.
1868  *   3) allocate the next available block on the block rotor for the
1869  *      specified cylinder group.
1870  * Note that this routine only allocates fs_bsize blocks; these
1871  * blocks may be fragmented by the routine that allocates them.
1872  */
1873 static ufs2_daddr_t
1874 ffs_alloccgblk(struct inode *ip,
1875 	struct buf *bp,
1876 	ufs2_daddr_t bpref,
1877 	int size)
1878 {
1879 	struct fs *fs;
1880 	struct cg *cgp;
1881 	struct ufsmount *ump;
1882 	ufs1_daddr_t bno;
1883 	ufs2_daddr_t blkno;
1884 	uint8_t *blksfree;
1885 	int i, cgbpref;
1886 
1887 	ump = ITOUMP(ip);
1888 	fs = ump->um_fs;
1889 	mtx_assert(UFS_MTX(ump), MA_OWNED);
1890 	cgp = (struct cg *)bp->b_data;
1891 	blksfree = cg_blksfree(cgp);
1892 	if (bpref == 0) {
1893 		bpref = cgbase(fs, cgp->cg_cgx) + cgp->cg_rotor + fs->fs_frag;
1894 	} else if ((cgbpref = dtog(fs, bpref)) != cgp->cg_cgx) {
1895 		/* map bpref to correct zone in this cg */
1896 		if (bpref < cgdata(fs, cgbpref))
1897 			bpref = cgmeta(fs, cgp->cg_cgx);
1898 		else
1899 			bpref = cgdata(fs, cgp->cg_cgx);
1900 	}
1901 	/*
1902 	 * if the requested block is available, use it
1903 	 */
1904 	bno = dtogd(fs, blknum(fs, bpref));
1905 	if (ffs_isblock(fs, blksfree, fragstoblks(fs, bno)))
1906 		goto gotit;
1907 	/*
1908 	 * Take the next available block in this cylinder group.
1909 	 */
1910 	bno = ffs_mapsearch(fs, cgp, bpref, (int)fs->fs_frag);
1911 	if (bno < 0)
1912 		return (0);
1913 	/* Update cg_rotor only if allocated from the data zone */
1914 	if (bno >= dtogd(fs, cgdata(fs, cgp->cg_cgx)))
1915 		cgp->cg_rotor = bno;
1916 gotit:
1917 	blkno = fragstoblks(fs, bno);
1918 	ffs_clrblock(fs, blksfree, (long)blkno);
1919 	ffs_clusteracct(fs, cgp, blkno, -1);
1920 	cgp->cg_cs.cs_nbfree--;
1921 	fs->fs_cstotal.cs_nbfree--;
1922 	fs->fs_cs(fs, cgp->cg_cgx).cs_nbfree--;
1923 	fs->fs_fmod = 1;
1924 	blkno = cgbase(fs, cgp->cg_cgx) + bno;
1925 	/*
1926 	 * If the caller didn't want the whole block free the frags here.
1927 	 */
1928 	size = numfrags(fs, size);
1929 	if (size != fs->fs_frag) {
1930 		bno = dtogd(fs, blkno);
1931 		for (i = size; i < fs->fs_frag; i++)
1932 			setbit(blksfree, bno + i);
1933 		i = fs->fs_frag - size;
1934 		cgp->cg_cs.cs_nffree += i;
1935 		fs->fs_cstotal.cs_nffree += i;
1936 		fs->fs_cs(fs, cgp->cg_cgx).cs_nffree += i;
1937 		fs->fs_fmod = 1;
1938 		cgp->cg_frsum[i]++;
1939 	}
1940 	/* XXX Fixme. */
1941 	UFS_UNLOCK(ump);
1942 	if (DOINGSOFTDEP(ITOV(ip)))
1943 		softdep_setup_blkmapdep(bp, UFSTOVFS(ump), blkno, size, 0);
1944 	UFS_LOCK(ump);
1945 	return (blkno);
1946 }
1947 
1948 /*
1949  * Determine whether a cluster can be allocated.
1950  *
1951  * We do not currently check for optimal rotational layout if there
1952  * are multiple choices in the same cylinder group. Instead we just
1953  * take the first one that we find following bpref.
1954  */
1955 static ufs2_daddr_t
1956 ffs_clusteralloc(struct inode *ip,
1957 	uint64_t cg,
1958 	ufs2_daddr_t bpref,
1959 	int len)
1960 {
1961 	struct fs *fs;
1962 	struct cg *cgp;
1963 	struct buf *bp;
1964 	struct ufsmount *ump;
1965 	int i, run, bit, map, got, error;
1966 	ufs2_daddr_t bno;
1967 	uint8_t *mapp;
1968 	int32_t *lp;
1969 	uint8_t *blksfree;
1970 
1971 	ump = ITOUMP(ip);
1972 	fs = ump->um_fs;
1973 	if (fs->fs_maxcluster[cg] < len)
1974 		return (0);
1975 	UFS_UNLOCK(ump);
1976 	if ((error = ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp)) != 0) {
1977 		ffs_checkcgintegrity(fs, cg, error);
1978 		UFS_LOCK(ump);
1979 		return (0);
1980 	}
1981 	/*
1982 	 * Check to see if a cluster of the needed size (or bigger) is
1983 	 * available in this cylinder group.
1984 	 */
1985 	lp = &cg_clustersum(cgp)[len];
1986 	for (i = len; i <= fs->fs_contigsumsize; i++)
1987 		if (*lp++ > 0)
1988 			break;
1989 	if (i > fs->fs_contigsumsize) {
1990 		/*
1991 		 * This is the first time looking for a cluster in this
1992 		 * cylinder group. Update the cluster summary information
1993 		 * to reflect the true maximum sized cluster so that
1994 		 * future cluster allocation requests can avoid reading
1995 		 * the cylinder group map only to find no clusters.
1996 		 */
1997 		lp = &cg_clustersum(cgp)[len - 1];
1998 		for (i = len - 1; i > 0; i--)
1999 			if (*lp-- > 0)
2000 				break;
2001 		UFS_LOCK(ump);
2002 		fs->fs_maxcluster[cg] = i;
2003 		brelse(bp);
2004 		return (0);
2005 	}
2006 	/*
2007 	 * Search the cluster map to find a big enough cluster.
2008 	 * We take the first one that we find, even if it is larger
2009 	 * than we need as we prefer to get one close to the previous
2010 	 * block allocation. We do not search before the current
2011 	 * preference point as we do not want to allocate a block
2012 	 * that is allocated before the previous one (as we will
2013 	 * then have to wait for another pass of the elevator
2014 	 * algorithm before it will be read). We prefer to fail and
2015 	 * be recalled to try an allocation in the next cylinder group.
2016 	 */
2017 	if (dtog(fs, bpref) != cg)
2018 		bpref = cgdata(fs, cg);
2019 	else
2020 		bpref = blknum(fs, bpref);
2021 	bpref = fragstoblks(fs, dtogd(fs, bpref));
2022 	mapp = &cg_clustersfree(cgp)[bpref / NBBY];
2023 	map = *mapp++;
2024 	bit = 1 << (bpref % NBBY);
2025 	for (run = 0, got = bpref; got < cgp->cg_nclusterblks; got++) {
2026 		if ((map & bit) == 0) {
2027 			run = 0;
2028 		} else {
2029 			run++;
2030 			if (run == len)
2031 				break;
2032 		}
2033 		if ((got & (NBBY - 1)) != (NBBY - 1)) {
2034 			bit <<= 1;
2035 		} else {
2036 			map = *mapp++;
2037 			bit = 1;
2038 		}
2039 	}
2040 	if (got >= cgp->cg_nclusterblks) {
2041 		UFS_LOCK(ump);
2042 		brelse(bp);
2043 		return (0);
2044 	}
2045 	/*
2046 	 * Allocate the cluster that we have found.
2047 	 */
2048 	blksfree = cg_blksfree(cgp);
2049 	for (i = 1; i <= len; i++)
2050 		if (!ffs_isblock(fs, blksfree, got - run + i))
2051 			panic("ffs_clusteralloc: map mismatch");
2052 	bno = cgbase(fs, cg) + blkstofrags(fs, got - run + 1);
2053 	if (dtog(fs, bno) != cg)
2054 		panic("ffs_clusteralloc: allocated out of group");
2055 	len = blkstofrags(fs, len);
2056 	UFS_LOCK(ump);
2057 	for (i = 0; i < len; i += fs->fs_frag)
2058 		if (ffs_alloccgblk(ip, bp, bno + i, fs->fs_bsize) != bno + i)
2059 			panic("ffs_clusteralloc: lost block");
2060 	ACTIVECLEAR(fs, cg);
2061 	UFS_UNLOCK(ump);
2062 	bdwrite(bp);
2063 	return (bno);
2064 }
2065 
2066 static inline struct buf *
2067 getinobuf(struct inode *ip,
2068 	uint64_t cg,
2069 	uint32_t cginoblk,
2070 	int gbflags)
2071 {
2072 	struct fs *fs;
2073 
2074 	fs = ITOFS(ip);
2075 	return (getblk(ITODEVVP(ip), fsbtodb(fs, ino_to_fsba(fs,
2076 	    cg * fs->fs_ipg + cginoblk)), (int)fs->fs_bsize, 0, 0,
2077 	    gbflags));
2078 }
2079 
2080 /*
2081  * Synchronous inode initialization is needed only when barrier writes do not
2082  * work as advertised, and will impose a heavy cost on file creation in a newly
2083  * created filesystem.
2084  */
2085 static int doasyncinodeinit = 1;
2086 SYSCTL_INT(_vfs_ffs, OID_AUTO, doasyncinodeinit, CTLFLAG_RWTUN,
2087     &doasyncinodeinit, 0,
2088     "Perform inode block initialization using asynchronous writes");
2089 
2090 /*
2091  * Determine whether an inode can be allocated.
2092  *
2093  * Check to see if an inode is available, and if it is,
2094  * allocate it using the following policy:
2095  *   1) allocate the requested inode.
2096  *   2) allocate the next available inode after the requested
2097  *      inode in the specified cylinder group.
2098  */
2099 static ufs2_daddr_t
2100 ffs_nodealloccg(struct inode *ip,
2101 	uint64_t cg,
2102 	ufs2_daddr_t ipref,
2103 	int mode,
2104 	int unused)
2105 {
2106 	struct fs *fs;
2107 	struct cg *cgp;
2108 	struct buf *bp, *ibp;
2109 	struct ufsmount *ump;
2110 	uint8_t *inosused, *loc;
2111 	struct ufs2_dinode *dp2;
2112 	int error, start, len, i;
2113 	uint32_t old_initediblk;
2114 
2115 	ump = ITOUMP(ip);
2116 	fs = ump->um_fs;
2117 check_nifree:
2118 	if (fs->fs_cs(fs, cg).cs_nifree == 0)
2119 		return (0);
2120 	UFS_UNLOCK(ump);
2121 	if ((error = ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp)) != 0) {
2122 		ffs_checkcgintegrity(fs, cg, error);
2123 		UFS_LOCK(ump);
2124 		return (0);
2125 	}
2126 restart:
2127 	if (cgp->cg_cs.cs_nifree == 0) {
2128 		brelse(bp);
2129 		UFS_LOCK(ump);
2130 		return (0);
2131 	}
2132 	inosused = cg_inosused(cgp);
2133 	if (ipref) {
2134 		ipref %= fs->fs_ipg;
2135 		if (isclr(inosused, ipref))
2136 			goto gotit;
2137 	}
2138 	start = cgp->cg_irotor / NBBY;
2139 	len = howmany(fs->fs_ipg - cgp->cg_irotor, NBBY);
2140 	loc = memcchr(&inosused[start], 0xff, len);
2141 	if (loc == NULL) {
2142 		len = start + 1;
2143 		start = 0;
2144 		loc = memcchr(&inosused[start], 0xff, len);
2145 		if (loc == NULL) {
2146 			printf("cg = %ju, irotor = %ld, fs = %s\n",
2147 			    (intmax_t)cg, (long)cgp->cg_irotor, fs->fs_fsmnt);
2148 			panic("ffs_nodealloccg: map corrupted");
2149 			/* NOTREACHED */
2150 		}
2151 	}
2152 	ipref = (loc - inosused) * NBBY + ffs(~*loc) - 1;
2153 gotit:
2154 	/*
2155 	 * Check to see if we need to initialize more inodes.
2156 	 */
2157 	if (fs->fs_magic == FS_UFS2_MAGIC &&
2158 	    ipref + INOPB(fs) > cgp->cg_initediblk &&
2159 	    cgp->cg_initediblk < cgp->cg_niblk) {
2160 		old_initediblk = cgp->cg_initediblk;
2161 
2162 		/*
2163 		 * Free the cylinder group lock before writing the
2164 		 * initialized inode block.  Entering the
2165 		 * babarrierwrite() with the cylinder group lock
2166 		 * causes lock order violation between the lock and
2167 		 * snaplk.
2168 		 *
2169 		 * Another thread can decide to initialize the same
2170 		 * inode block, but whichever thread first gets the
2171 		 * cylinder group lock after writing the newly
2172 		 * allocated inode block will update it and the other
2173 		 * will realize that it has lost and leave the
2174 		 * cylinder group unchanged.
2175 		 */
2176 		ibp = getinobuf(ip, cg, old_initediblk, GB_LOCK_NOWAIT);
2177 		brelse(bp);
2178 		if (ibp == NULL) {
2179 			/*
2180 			 * The inode block buffer is already owned by
2181 			 * another thread, which must initialize it.
2182 			 * Wait on the buffer to allow another thread
2183 			 * to finish the updates, with dropped cg
2184 			 * buffer lock, then retry.
2185 			 */
2186 			ibp = getinobuf(ip, cg, old_initediblk, 0);
2187 			brelse(ibp);
2188 			UFS_LOCK(ump);
2189 			goto check_nifree;
2190 		}
2191 		bzero(ibp->b_data, (int)fs->fs_bsize);
2192 		dp2 = (struct ufs2_dinode *)(ibp->b_data);
2193 		for (i = 0; i < INOPB(fs); i++) {
2194 			while (dp2->di_gen == 0)
2195 				dp2->di_gen = arc4random();
2196 			dp2++;
2197 		}
2198 
2199 		/*
2200 		 * Rather than adding a soft updates dependency to ensure
2201 		 * that the new inode block is written before it is claimed
2202 		 * by the cylinder group map, we just do a barrier write
2203 		 * here. The barrier write will ensure that the inode block
2204 		 * gets written before the updated cylinder group map can be
2205 		 * written. The barrier write should only slow down bulk
2206 		 * loading of newly created filesystems.
2207 		 */
2208 		if (doasyncinodeinit)
2209 			babarrierwrite(ibp);
2210 		else
2211 			bwrite(ibp);
2212 
2213 		/*
2214 		 * After the inode block is written, try to update the
2215 		 * cg initediblk pointer.  If another thread beat us
2216 		 * to it, then leave it unchanged as the other thread
2217 		 * has already set it correctly.
2218 		 */
2219 		error = ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp);
2220 		UFS_LOCK(ump);
2221 		ACTIVECLEAR(fs, cg);
2222 		UFS_UNLOCK(ump);
2223 		if (error != 0)
2224 			return (error);
2225 		if (cgp->cg_initediblk == old_initediblk)
2226 			cgp->cg_initediblk += INOPB(fs);
2227 		goto restart;
2228 	}
2229 	cgp->cg_irotor = ipref;
2230 	UFS_LOCK(ump);
2231 	ACTIVECLEAR(fs, cg);
2232 	setbit(inosused, ipref);
2233 	cgp->cg_cs.cs_nifree--;
2234 	fs->fs_cstotal.cs_nifree--;
2235 	fs->fs_cs(fs, cg).cs_nifree--;
2236 	fs->fs_fmod = 1;
2237 	if ((mode & IFMT) == IFDIR) {
2238 		cgp->cg_cs.cs_ndir++;
2239 		fs->fs_cstotal.cs_ndir++;
2240 		fs->fs_cs(fs, cg).cs_ndir++;
2241 	}
2242 	UFS_UNLOCK(ump);
2243 	if (DOINGSOFTDEP(ITOV(ip)))
2244 		softdep_setup_inomapdep(bp, ip, cg * fs->fs_ipg + ipref, mode);
2245 	bdwrite(bp);
2246 	return ((ino_t)(cg * fs->fs_ipg + ipref));
2247 }
2248 
2249 /*
2250  * Free a block or fragment.
2251  *
2252  * The specified block or fragment is placed back in the
2253  * free map. If a fragment is deallocated, a possible
2254  * block reassembly is checked.
2255  */
2256 static void
2257 ffs_blkfree_cg(struct ufsmount *ump,
2258 	struct fs *fs,
2259 	struct vnode *devvp,
2260 	ufs2_daddr_t bno,
2261 	long size,
2262 	ino_t inum,
2263 	struct workhead *dephd)
2264 {
2265 	struct mount *mp;
2266 	struct cg *cgp;
2267 	struct buf *bp;
2268 	daddr_t dbn;
2269 	ufs1_daddr_t fragno, cgbno;
2270 	int i, blk, frags, bbase, error;
2271 	uint64_t cg;
2272 	uint8_t *blksfree;
2273 	struct cdev *dev;
2274 
2275 	cg = dtog(fs, bno);
2276 	if (devvp->v_type == VREG) {
2277 		/* devvp is a snapshot */
2278 		MPASS(devvp->v_mount->mnt_data == ump);
2279 		dev = ump->um_devvp->v_rdev;
2280 	} else if (devvp->v_type == VCHR) {
2281 		/*
2282 		 * devvp is a normal disk device
2283 		 * XXXKIB: devvp is not locked there, v_rdev access depends on
2284 		 * busy mount, which prevents mntfs devvp from reclamation.
2285 		 */
2286 		dev = devvp->v_rdev;
2287 	} else
2288 		return;
2289 #ifdef INVARIANTS
2290 	if ((uint64_t)size > fs->fs_bsize || fragoff(fs, size) != 0 ||
2291 	    fragnum(fs, bno) + numfrags(fs, size) > fs->fs_frag) {
2292 		printf("dev=%s, bno = %jd, bsize = %ld, size = %ld, fs = %s\n",
2293 		    devtoname(dev), (intmax_t)bno, (long)fs->fs_bsize,
2294 		    size, fs->fs_fsmnt);
2295 		panic("ffs_blkfree_cg: invalid size");
2296 	}
2297 #endif
2298 	if ((uint64_t)bno >= fs->fs_size) {
2299 		printf("bad block %jd, ino %ju\n", (intmax_t)bno,
2300 		    (intmax_t)inum);
2301 		ffs_fserr(fs, inum, "bad block");
2302 		return;
2303 	}
2304 	if ((error = ffs_getcg(fs, devvp, cg, GB_CVTENXIO, &bp, &cgp)) != 0) {
2305 		if (!MOUNTEDSOFTDEP(UFSTOVFS(ump)) || devvp->v_type != VCHR)
2306 			return;
2307 		/*
2308 		 * Would like to just downgrade to read-only. Until that
2309 		 * capability is available, just toss the cylinder group
2310 		 * update and mark the filesystem as needing to run fsck.
2311 		 */
2312 		fs->fs_flags |= FS_NEEDSFSCK;
2313 		if (devvp->v_type == VREG)
2314 			dbn = fragstoblks(fs, cgtod(fs, cg));
2315 		else
2316 			dbn = fsbtodb(fs, cgtod(fs, cg));
2317 		error = getblkx(devvp, dbn, dbn, fs->fs_cgsize, 0, 0, 0, &bp);
2318 		KASSERT(error == 0, ("getblkx failed"));
2319 		softdep_setup_blkfree(UFSTOVFS(ump), bp, bno,
2320 		    numfrags(fs, size), dephd, true);
2321 		bp->b_flags |= B_RELBUF | B_NOCACHE;
2322 		bp->b_flags &= ~B_CACHE;
2323 		bawrite(bp);
2324 		return;
2325 	}
2326 	cgbno = dtogd(fs, bno);
2327 	blksfree = cg_blksfree(cgp);
2328 	UFS_LOCK(ump);
2329 	if (size == fs->fs_bsize) {
2330 		fragno = fragstoblks(fs, cgbno);
2331 		if (!ffs_isfreeblock(fs, blksfree, fragno)) {
2332 			if (devvp->v_type == VREG) {
2333 				UFS_UNLOCK(ump);
2334 				/* devvp is a snapshot */
2335 				brelse(bp);
2336 				return;
2337 			}
2338 			printf("dev = %s, block = %jd, fs = %s\n",
2339 			    devtoname(dev), (intmax_t)bno, fs->fs_fsmnt);
2340 			panic("ffs_blkfree_cg: freeing free block");
2341 		}
2342 		ffs_setblock(fs, blksfree, fragno);
2343 		ffs_clusteracct(fs, cgp, fragno, 1);
2344 		cgp->cg_cs.cs_nbfree++;
2345 		fs->fs_cstotal.cs_nbfree++;
2346 		fs->fs_cs(fs, cg).cs_nbfree++;
2347 	} else {
2348 		bbase = cgbno - fragnum(fs, cgbno);
2349 		/*
2350 		 * decrement the counts associated with the old frags
2351 		 */
2352 		blk = blkmap(fs, blksfree, bbase);
2353 		ffs_fragacct(fs, blk, cgp->cg_frsum, -1);
2354 		/*
2355 		 * deallocate the fragment
2356 		 */
2357 		frags = numfrags(fs, size);
2358 		for (i = 0; i < frags; i++) {
2359 			if (isset(blksfree, cgbno + i)) {
2360 				printf("dev = %s, block = %jd, fs = %s\n",
2361 				    devtoname(dev), (intmax_t)(bno + i),
2362 				    fs->fs_fsmnt);
2363 				panic("ffs_blkfree_cg: freeing free frag");
2364 			}
2365 			setbit(blksfree, cgbno + i);
2366 		}
2367 		cgp->cg_cs.cs_nffree += i;
2368 		fs->fs_cstotal.cs_nffree += i;
2369 		fs->fs_cs(fs, cg).cs_nffree += i;
2370 		/*
2371 		 * add back in counts associated with the new frags
2372 		 */
2373 		blk = blkmap(fs, blksfree, bbase);
2374 		ffs_fragacct(fs, blk, cgp->cg_frsum, 1);
2375 		/*
2376 		 * if a complete block has been reassembled, account for it
2377 		 */
2378 		fragno = fragstoblks(fs, bbase);
2379 		if (ffs_isblock(fs, blksfree, fragno)) {
2380 			cgp->cg_cs.cs_nffree -= fs->fs_frag;
2381 			fs->fs_cstotal.cs_nffree -= fs->fs_frag;
2382 			fs->fs_cs(fs, cg).cs_nffree -= fs->fs_frag;
2383 			ffs_clusteracct(fs, cgp, fragno, 1);
2384 			cgp->cg_cs.cs_nbfree++;
2385 			fs->fs_cstotal.cs_nbfree++;
2386 			fs->fs_cs(fs, cg).cs_nbfree++;
2387 		}
2388 	}
2389 	fs->fs_fmod = 1;
2390 	ACTIVECLEAR(fs, cg);
2391 	UFS_UNLOCK(ump);
2392 	mp = UFSTOVFS(ump);
2393 	if (MOUNTEDSOFTDEP(mp) && devvp->v_type == VCHR)
2394 		softdep_setup_blkfree(UFSTOVFS(ump), bp, bno,
2395 		    numfrags(fs, size), dephd, false);
2396 	bdwrite(bp);
2397 }
2398 
2399 /*
2400  * Structures and routines associated with trim management.
2401  *
2402  * The following requests are passed to trim_lookup to indicate
2403  * the actions that should be taken.
2404  */
2405 #define	NEW	1	/* if found, error else allocate and hash it */
2406 #define	OLD	2	/* if not found, error, else return it */
2407 #define	REPLACE	3	/* if not found, error else unhash and reallocate it */
2408 #define	DONE	4	/* if not found, error else unhash and return it */
2409 #define	SINGLE	5	/* don't look up, just allocate it and don't hash it */
2410 
2411 MALLOC_DEFINE(M_TRIM, "ufs_trim", "UFS trim structures");
2412 
2413 #define	TRIMLIST_HASH(ump, key) \
2414 	(&(ump)->um_trimhash[(key) & (ump)->um_trimlisthashsize])
2415 
2416 /*
2417  * These structures describe each of the block free requests aggregated
2418  * together to make up a trim request.
2419  */
2420 struct trim_blkreq {
2421 	TAILQ_ENTRY(trim_blkreq) blkreqlist;
2422 	ufs2_daddr_t bno;
2423 	long size;
2424 	struct workhead *pdephd;
2425 	struct workhead dephd;
2426 };
2427 
2428 /*
2429  * Description of a trim request.
2430  */
2431 struct ffs_blkfree_trim_params {
2432 	TAILQ_HEAD(, trim_blkreq) blklist;
2433 	LIST_ENTRY(ffs_blkfree_trim_params) hashlist;
2434 	struct task task;
2435 	struct ufsmount *ump;
2436 	struct vnode *devvp;
2437 	ino_t inum;
2438 	ufs2_daddr_t bno;
2439 	long size;
2440 	long key;
2441 };
2442 
2443 static void	ffs_blkfree_trim_completed(struct buf *);
2444 static void	ffs_blkfree_trim_task(void *ctx, int pending __unused);
2445 static struct	ffs_blkfree_trim_params *trim_lookup(struct ufsmount *,
2446 		    struct vnode *, ufs2_daddr_t, long, ino_t, uint64_t, int);
2447 static void	ffs_blkfree_sendtrim(struct ffs_blkfree_trim_params *);
2448 
2449 /*
2450  * Called on trim completion to start a task to free the associated block(s).
2451  */
2452 static void
2453 ffs_blkfree_trim_completed(struct buf *bp)
2454 {
2455 	struct ffs_blkfree_trim_params *tp;
2456 
2457 	tp = bp->b_fsprivate1;
2458 	free(bp, M_TRIM);
2459 	TASK_INIT(&tp->task, 0, ffs_blkfree_trim_task, tp);
2460 	taskqueue_enqueue(tp->ump->um_trim_tq, &tp->task);
2461 }
2462 
2463 /*
2464  * Trim completion task that free associated block(s).
2465  */
2466 static void
2467 ffs_blkfree_trim_task(void *ctx, int pending)
2468 {
2469 	struct ffs_blkfree_trim_params *tp;
2470 	struct trim_blkreq *blkelm;
2471 	struct ufsmount *ump;
2472 
2473 	tp = ctx;
2474 	ump = tp->ump;
2475 	while ((blkelm = TAILQ_FIRST(&tp->blklist)) != NULL) {
2476 		ffs_blkfree_cg(ump, ump->um_fs, tp->devvp, blkelm->bno,
2477 		    blkelm->size, tp->inum, blkelm->pdephd);
2478 		TAILQ_REMOVE(&tp->blklist, blkelm, blkreqlist);
2479 		free(blkelm, M_TRIM);
2480 	}
2481 	vn_finished_secondary_write(UFSTOVFS(ump));
2482 	UFS_LOCK(ump);
2483 	ump->um_trim_inflight -= 1;
2484 	ump->um_trim_inflight_blks -= numfrags(ump->um_fs, tp->size);
2485 	UFS_UNLOCK(ump);
2486 	free(tp, M_TRIM);
2487 }
2488 
2489 /*
2490  * Lookup a trim request by inode number.
2491  * Allocate if requested (NEW, REPLACE, SINGLE).
2492  */
2493 static struct ffs_blkfree_trim_params *
2494 trim_lookup(struct ufsmount *ump,
2495 	struct vnode *devvp,
2496 	ufs2_daddr_t bno,
2497 	long size,
2498 	ino_t inum,
2499 	uint64_t key,
2500 	int alloctype)
2501 {
2502 	struct trimlist_hashhead *tphashhead;
2503 	struct ffs_blkfree_trim_params *tp, *ntp;
2504 
2505 	ntp = malloc(sizeof(struct ffs_blkfree_trim_params), M_TRIM, M_WAITOK);
2506 	if (alloctype != SINGLE) {
2507 		KASSERT(key >= FIRST_VALID_KEY, ("trim_lookup: invalid key"));
2508 		UFS_LOCK(ump);
2509 		tphashhead = TRIMLIST_HASH(ump, key);
2510 		LIST_FOREACH(tp, tphashhead, hashlist)
2511 			if (key == tp->key)
2512 				break;
2513 	}
2514 	switch (alloctype) {
2515 	case NEW:
2516 		KASSERT(tp == NULL, ("trim_lookup: found trim"));
2517 		break;
2518 	case OLD:
2519 		KASSERT(tp != NULL,
2520 		    ("trim_lookup: missing call to ffs_blkrelease_start()"));
2521 		UFS_UNLOCK(ump);
2522 		free(ntp, M_TRIM);
2523 		return (tp);
2524 	case REPLACE:
2525 		KASSERT(tp != NULL, ("trim_lookup: missing REPLACE trim"));
2526 		LIST_REMOVE(tp, hashlist);
2527 		/* tp will be freed by caller */
2528 		break;
2529 	case DONE:
2530 		KASSERT(tp != NULL, ("trim_lookup: missing DONE trim"));
2531 		LIST_REMOVE(tp, hashlist);
2532 		UFS_UNLOCK(ump);
2533 		free(ntp, M_TRIM);
2534 		return (tp);
2535 	}
2536 	TAILQ_INIT(&ntp->blklist);
2537 	ntp->ump = ump;
2538 	ntp->devvp = devvp;
2539 	ntp->bno = bno;
2540 	ntp->size = size;
2541 	ntp->inum = inum;
2542 	ntp->key = key;
2543 	if (alloctype != SINGLE) {
2544 		LIST_INSERT_HEAD(tphashhead, ntp, hashlist);
2545 		UFS_UNLOCK(ump);
2546 	}
2547 	return (ntp);
2548 }
2549 
2550 /*
2551  * Dispatch a trim request.
2552  */
2553 static void
2554 ffs_blkfree_sendtrim(struct ffs_blkfree_trim_params *tp)
2555 {
2556 	struct ufsmount *ump;
2557 	struct mount *mp;
2558 	struct buf *bp;
2559 
2560 	/*
2561 	 * Postpone the set of the free bit in the cg bitmap until the
2562 	 * BIO_DELETE is completed.  Otherwise, due to disk queue
2563 	 * reordering, TRIM might be issued after we reuse the block
2564 	 * and write some new data into it.
2565 	 */
2566 	ump = tp->ump;
2567 	bp = malloc(sizeof(*bp), M_TRIM, M_WAITOK | M_ZERO);
2568 	bp->b_iocmd = BIO_DELETE;
2569 	bp->b_iooffset = dbtob(fsbtodb(ump->um_fs, tp->bno));
2570 	bp->b_iodone = ffs_blkfree_trim_completed;
2571 	bp->b_bcount = tp->size;
2572 	bp->b_fsprivate1 = tp;
2573 	UFS_LOCK(ump);
2574 	ump->um_trim_total += 1;
2575 	ump->um_trim_inflight += 1;
2576 	ump->um_trim_inflight_blks += numfrags(ump->um_fs, tp->size);
2577 	ump->um_trim_total_blks += numfrags(ump->um_fs, tp->size);
2578 	UFS_UNLOCK(ump);
2579 
2580 	mp = UFSTOVFS(ump);
2581 	vn_start_secondary_write(NULL, &mp, 0);
2582 	g_vfs_strategy(ump->um_bo, bp);
2583 }
2584 
2585 /*
2586  * Allocate a new key to use to identify a range of blocks.
2587  */
2588 uint64_t
2589 ffs_blkrelease_start(struct ufsmount *ump,
2590 	struct vnode *devvp,
2591 	ino_t inum)
2592 {
2593 	static u_long masterkey;
2594 	uint64_t key;
2595 
2596 	if (((ump->um_flags & UM_CANDELETE) == 0) || dotrimcons == 0)
2597 		return (SINGLETON_KEY);
2598 	do {
2599 		key = atomic_fetchadd_long(&masterkey, 1);
2600 	} while (key < FIRST_VALID_KEY);
2601 	(void) trim_lookup(ump, devvp, 0, 0, inum, key, NEW);
2602 	return (key);
2603 }
2604 
2605 /*
2606  * Deallocate a key that has been used to identify a range of blocks.
2607  */
2608 void
2609 ffs_blkrelease_finish(struct ufsmount *ump, uint64_t key)
2610 {
2611 	struct ffs_blkfree_trim_params *tp;
2612 
2613 	if (((ump->um_flags & UM_CANDELETE) == 0) || dotrimcons == 0)
2614 		return;
2615 	/*
2616 	 * If the vfs.ffs.dotrimcons sysctl option is enabled while
2617 	 * a file deletion is active, specifically after a call
2618 	 * to ffs_blkrelease_start() but before the call to
2619 	 * ffs_blkrelease_finish(), ffs_blkrelease_start() will
2620 	 * have handed out SINGLETON_KEY rather than starting a
2621 	 * collection sequence. Thus if we get a SINGLETON_KEY
2622 	 * passed to ffs_blkrelease_finish(), we just return rather
2623 	 * than trying to finish the nonexistent sequence.
2624 	 */
2625 	if (key == SINGLETON_KEY) {
2626 #ifdef INVARIANTS
2627 		printf("%s: vfs.ffs.dotrimcons enabled on active filesystem\n",
2628 		    ump->um_mountp->mnt_stat.f_mntonname);
2629 #endif
2630 		return;
2631 	}
2632 	/*
2633 	 * We are done with sending blocks using this key. Look up the key
2634 	 * using the DONE alloctype (in tp) to request that it be unhashed
2635 	 * as we will not be adding to it. If the key has never been used,
2636 	 * tp->size will be zero, so we can just free tp. Otherwise the call
2637 	 * to ffs_blkfree_sendtrim(tp) causes the block range described by
2638 	 * tp to be issued (and then tp to be freed).
2639 	 */
2640 	tp = trim_lookup(ump, NULL, 0, 0, 0, key, DONE);
2641 	if (tp->size == 0)
2642 		free(tp, M_TRIM);
2643 	else
2644 		ffs_blkfree_sendtrim(tp);
2645 }
2646 
2647 /*
2648  * Setup to free a block or fragment.
2649  *
2650  * Check for snapshots that might want to claim the block.
2651  * If trims are requested, prepare a trim request. Attempt to
2652  * aggregate consecutive blocks into a single trim request.
2653  */
2654 void
2655 ffs_blkfree(struct ufsmount *ump,
2656 	struct fs *fs,
2657 	struct vnode *devvp,
2658 	ufs2_daddr_t bno,
2659 	long size,
2660 	ino_t inum,
2661 	__enum_uint8(vtype) vtype,
2662 	struct workhead *dephd,
2663 	uint64_t key)
2664 {
2665 	struct ffs_blkfree_trim_params *tp, *ntp;
2666 	struct trim_blkreq *blkelm;
2667 
2668 	/*
2669 	 * Check to see if a snapshot wants to claim the block.
2670 	 * Check that devvp is a normal disk device, not a snapshot,
2671 	 * it has a snapshot(s) associated with it, and one of the
2672 	 * snapshots wants to claim the block.
2673 	 */
2674 	if (devvp->v_type == VCHR &&
2675 	    (devvp->v_vflag & VV_COPYONWRITE) &&
2676 	    ffs_snapblkfree(fs, devvp, bno, size, inum, vtype, dephd)) {
2677 		return;
2678 	}
2679 	/*
2680 	 * Nothing to delay if TRIM is not required for this block or TRIM
2681 	 * is disabled or the operation is performed on a snapshot.
2682 	 */
2683 	if (key == NOTRIM_KEY || ((ump->um_flags & UM_CANDELETE) == 0) ||
2684 	    devvp->v_type == VREG) {
2685 		ffs_blkfree_cg(ump, fs, devvp, bno, size, inum, dephd);
2686 		return;
2687 	}
2688 	blkelm = malloc(sizeof(struct trim_blkreq), M_TRIM, M_WAITOK);
2689 	blkelm->bno = bno;
2690 	blkelm->size = size;
2691 	if (dephd == NULL) {
2692 		blkelm->pdephd = NULL;
2693 	} else {
2694 		LIST_INIT(&blkelm->dephd);
2695 		LIST_SWAP(dephd, &blkelm->dephd, worklist, wk_list);
2696 		blkelm->pdephd = &blkelm->dephd;
2697 	}
2698 	if (key == SINGLETON_KEY) {
2699 		/*
2700 		 * Just a single non-contiguous piece. Use the SINGLE
2701 		 * alloctype to return a trim request that will not be
2702 		 * hashed for future lookup.
2703 		 */
2704 		tp = trim_lookup(ump, devvp, bno, size, inum, key, SINGLE);
2705 		TAILQ_INSERT_HEAD(&tp->blklist, blkelm, blkreqlist);
2706 		ffs_blkfree_sendtrim(tp);
2707 		return;
2708 	}
2709 	/*
2710 	 * The callers of this function are not tracking whether or not
2711 	 * the blocks are contiguous. They are just saying that they
2712 	 * are freeing a set of blocks. It is this code that determines
2713 	 * the pieces of that range that are actually contiguous.
2714 	 *
2715 	 * Calling ffs_blkrelease_start() will have created an entry
2716 	 * that we will use.
2717 	 */
2718 	tp = trim_lookup(ump, devvp, bno, size, inum, key, OLD);
2719 	if (tp->size == 0) {
2720 		/*
2721 		 * First block of a potential range, set block and size
2722 		 * for the trim block.
2723 		 */
2724 		tp->bno = bno;
2725 		tp->size = size;
2726 		TAILQ_INSERT_HEAD(&tp->blklist, blkelm, blkreqlist);
2727 		return;
2728 	}
2729 	/*
2730 	 * If this block is a continuation of the range (either
2731 	 * follows at the end or preceeds in the front) then we
2732 	 * add it to the front or back of the list and return.
2733 	 *
2734 	 * If it is not a continuation of the trim that we were
2735 	 * building, using the REPLACE alloctype, we request that
2736 	 * the old trim request (still in tp) be unhashed and a
2737 	 * new range started (in ntp). The ffs_blkfree_sendtrim(tp)
2738 	 * call causes the block range described by tp to be issued
2739 	 * (and then tp to be freed).
2740 	 */
2741 	if (bno + numfrags(fs, size) == tp->bno) {
2742 		TAILQ_INSERT_HEAD(&tp->blklist, blkelm, blkreqlist);
2743 		tp->bno = bno;
2744 		tp->size += size;
2745 		return;
2746 	} else if (bno == tp->bno + numfrags(fs, tp->size)) {
2747 		TAILQ_INSERT_TAIL(&tp->blklist, blkelm, blkreqlist);
2748 		tp->size += size;
2749 		return;
2750 	}
2751 	ntp = trim_lookup(ump, devvp, bno, size, inum, key, REPLACE);
2752 	TAILQ_INSERT_HEAD(&ntp->blklist, blkelm, blkreqlist);
2753 	ffs_blkfree_sendtrim(tp);
2754 }
2755 
2756 #ifdef INVARIANTS
2757 /*
2758  * Verify allocation of a block or fragment.
2759  * Return 1 if block or fragment is free.
2760  */
2761 static int
2762 ffs_checkfreeblk(struct inode *ip,
2763 	ufs2_daddr_t bno,
2764 	long size)
2765 {
2766 	struct fs *fs;
2767 	struct cg *cgp;
2768 	struct buf *bp;
2769 	ufs1_daddr_t cgbno;
2770 	int i, frags, blkalloced;
2771 	uint8_t *blksfree;
2772 
2773 	fs = ITOFS(ip);
2774 	if ((uint64_t)size > fs->fs_bsize || fragoff(fs, size) != 0) {
2775 		printf("bsize = %ld, size = %ld, fs = %s\n",
2776 		    (long)fs->fs_bsize, size, fs->fs_fsmnt);
2777 		panic("ffs_checkfreeblk: bad size");
2778 	}
2779 	if ((uint64_t)bno >= fs->fs_size)
2780 		panic("ffs_checkfreeblk: too big block %jd", (intmax_t)bno);
2781 	if (ffs_getcg(fs, ITODEVVP(ip), dtog(fs, bno), 0, &bp, &cgp) != 0)
2782 		return (0);
2783 	blksfree = cg_blksfree(cgp);
2784 	cgbno = dtogd(fs, bno);
2785 	if (size == fs->fs_bsize) {
2786 		blkalloced = ffs_isblock(fs, blksfree, fragstoblks(fs, cgbno));
2787 	} else {
2788 		frags = numfrags(fs, size);
2789 		for (blkalloced = 0, i = 0; i < frags; i++)
2790 			if (isset(blksfree, cgbno + i))
2791 				blkalloced++;
2792 		if (blkalloced != 0 && blkalloced != frags)
2793 			panic("ffs_checkfreeblk: partially free fragment");
2794 	}
2795 	brelse(bp);
2796 	return (blkalloced == 0);
2797 }
2798 #endif /* INVARIANTS */
2799 
2800 /*
2801  * Free an inode.
2802  */
2803 int
2804 ffs_vfree(struct vnode *pvp,
2805 	ino_t ino,
2806 	int mode)
2807 {
2808 	struct ufsmount *ump;
2809 
2810 	if (DOINGSOFTDEP(pvp)) {
2811 		softdep_freefile(pvp, ino, mode);
2812 		return (0);
2813 	}
2814 	ump = VFSTOUFS(pvp->v_mount);
2815 	return (ffs_freefile(ump, ump->um_fs, ump->um_devvp, ino, mode, NULL));
2816 }
2817 
2818 /*
2819  * Do the actual free operation.
2820  * The specified inode is placed back in the free map.
2821  */
2822 int
2823 ffs_freefile(struct ufsmount *ump,
2824 	struct fs *fs,
2825 	struct vnode *devvp,
2826 	ino_t ino,
2827 	int mode,
2828 	struct workhead *wkhd)
2829 {
2830 	struct cg *cgp;
2831 	struct buf *bp;
2832 	daddr_t dbn;
2833 	int error;
2834 	uint64_t cg;
2835 	uint8_t *inosused;
2836 	struct cdev *dev;
2837 	ino_t cgino;
2838 
2839 	cg = ino_to_cg(fs, ino);
2840 	if (devvp->v_type == VREG) {
2841 		/* devvp is a snapshot */
2842 		MPASS(devvp->v_mount->mnt_data == ump);
2843 		dev = ump->um_devvp->v_rdev;
2844 	} else if (devvp->v_type == VCHR) {
2845 		/* devvp is a normal disk device */
2846 		dev = devvp->v_rdev;
2847 	} else {
2848 		bp = NULL;
2849 		return (0);
2850 	}
2851 	if (ino >= fs->fs_ipg * fs->fs_ncg)
2852 		panic("ffs_freefile: range: dev = %s, ino = %ju, fs = %s",
2853 		    devtoname(dev), (uintmax_t)ino, fs->fs_fsmnt);
2854 	if ((error = ffs_getcg(fs, devvp, cg, GB_CVTENXIO, &bp, &cgp)) != 0) {
2855 		if (!MOUNTEDSOFTDEP(UFSTOVFS(ump)) || devvp->v_type != VCHR)
2856 			return (error);
2857 		/*
2858 		 * Would like to just downgrade to read-only. Until that
2859 		 * capability is available, just toss the cylinder group
2860 		 * update and mark the filesystem as needing to run fsck.
2861 		 */
2862 		fs->fs_flags |= FS_NEEDSFSCK;
2863 		if (devvp->v_type == VREG)
2864 			dbn = fragstoblks(fs, cgtod(fs, cg));
2865 		else
2866 			dbn = fsbtodb(fs, cgtod(fs, cg));
2867 		error = getblkx(devvp, dbn, dbn, fs->fs_cgsize, 0, 0, 0, &bp);
2868 		KASSERT(error == 0, ("getblkx failed"));
2869 		softdep_setup_inofree(UFSTOVFS(ump), bp, ino, wkhd, true);
2870 		bp->b_flags |= B_RELBUF | B_NOCACHE;
2871 		bp->b_flags &= ~B_CACHE;
2872 		bawrite(bp);
2873 		return (error);
2874 	}
2875 	inosused = cg_inosused(cgp);
2876 	cgino = ino % fs->fs_ipg;
2877 	if (isclr(inosused, cgino)) {
2878 		printf("dev = %s, ino = %ju, fs = %s\n", devtoname(dev),
2879 		    (uintmax_t)ino, fs->fs_fsmnt);
2880 		if (fs->fs_ronly == 0)
2881 			panic("ffs_freefile: freeing free inode");
2882 	}
2883 	clrbit(inosused, cgino);
2884 	if (cgino < cgp->cg_irotor)
2885 		cgp->cg_irotor = cgino;
2886 	cgp->cg_cs.cs_nifree++;
2887 	UFS_LOCK(ump);
2888 	fs->fs_cstotal.cs_nifree++;
2889 	fs->fs_cs(fs, cg).cs_nifree++;
2890 	if ((mode & IFMT) == IFDIR) {
2891 		cgp->cg_cs.cs_ndir--;
2892 		fs->fs_cstotal.cs_ndir--;
2893 		fs->fs_cs(fs, cg).cs_ndir--;
2894 	}
2895 	fs->fs_fmod = 1;
2896 	ACTIVECLEAR(fs, cg);
2897 	UFS_UNLOCK(ump);
2898 	if (MOUNTEDSOFTDEP(UFSTOVFS(ump)) && devvp->v_type == VCHR)
2899 		softdep_setup_inofree(UFSTOVFS(ump), bp, ino, wkhd, false);
2900 	bdwrite(bp);
2901 	return (0);
2902 }
2903 
2904 /*
2905  * Check to see if a file is free.
2906  * Used to check for allocated files in snapshots.
2907  * Return 1 if file is free.
2908  */
2909 int
2910 ffs_checkfreefile(struct fs *fs,
2911 	struct vnode *devvp,
2912 	ino_t ino)
2913 {
2914 	struct cg *cgp;
2915 	struct buf *bp;
2916 	int ret, error;
2917 	uint64_t cg;
2918 	uint8_t *inosused;
2919 
2920 	cg = ino_to_cg(fs, ino);
2921 	if ((devvp->v_type != VREG) && (devvp->v_type != VCHR))
2922 		return (1);
2923 	if (ino >= fs->fs_ipg * fs->fs_ncg)
2924 		return (1);
2925 	if ((error = ffs_getcg(fs, devvp, cg, 0, &bp, &cgp)) != 0)
2926 		return (1);
2927 	inosused = cg_inosused(cgp);
2928 	ino %= fs->fs_ipg;
2929 	ret = isclr(inosused, ino);
2930 	brelse(bp);
2931 	return (ret);
2932 }
2933 
2934 /*
2935  * Find a block of the specified size in the specified cylinder group.
2936  *
2937  * It is a panic if a request is made to find a block if none are
2938  * available.
2939  */
2940 static ufs1_daddr_t
2941 ffs_mapsearch(struct fs *fs,
2942 	struct cg *cgp,
2943 	ufs2_daddr_t bpref,
2944 	int allocsiz)
2945 {
2946 	ufs1_daddr_t bno;
2947 	int start, len, loc, i;
2948 	int blk, field, subfield, pos;
2949 	uint8_t *blksfree;
2950 
2951 	/*
2952 	 * find the fragment by searching through the free block
2953 	 * map for an appropriate bit pattern
2954 	 */
2955 	if (bpref)
2956 		start = dtogd(fs, bpref) / NBBY;
2957 	else
2958 		start = cgp->cg_frotor / NBBY;
2959 	blksfree = cg_blksfree(cgp);
2960 	len = howmany(fs->fs_fpg, NBBY) - start;
2961 	loc = scanc((uint64_t)len, (uint8_t *)&blksfree[start],
2962 		fragtbl[fs->fs_frag],
2963 		(uint8_t)(1 << (allocsiz - 1 + (fs->fs_frag % NBBY))));
2964 	if (loc == 0) {
2965 		len = start + 1;
2966 		start = 0;
2967 		loc = scanc((uint64_t)len, (uint8_t *)&blksfree[0],
2968 			fragtbl[fs->fs_frag],
2969 			(uint8_t)(1 << (allocsiz - 1 + (fs->fs_frag % NBBY))));
2970 		if (loc == 0) {
2971 			printf("start = %d, len = %d, fs = %s\n",
2972 			    start, len, fs->fs_fsmnt);
2973 			panic("ffs_alloccg: map corrupted");
2974 			/* NOTREACHED */
2975 		}
2976 	}
2977 	bno = (start + len - loc) * NBBY;
2978 	cgp->cg_frotor = bno;
2979 	/*
2980 	 * found the byte in the map
2981 	 * sift through the bits to find the selected frag
2982 	 */
2983 	for (i = bno + NBBY; bno < i; bno += fs->fs_frag) {
2984 		blk = blkmap(fs, blksfree, bno);
2985 		blk <<= 1;
2986 		field = around[allocsiz];
2987 		subfield = inside[allocsiz];
2988 		for (pos = 0; pos <= fs->fs_frag - allocsiz; pos++) {
2989 			if ((blk & field) == subfield)
2990 				return (bno + pos);
2991 			field <<= 1;
2992 			subfield <<= 1;
2993 		}
2994 	}
2995 	printf("bno = %ju, fs = %s\n", (intmax_t)bno, fs->fs_fsmnt);
2996 	panic("ffs_alloccg: block not in map");
2997 	return (-1);
2998 }
2999 
3000 /*
3001  * Fetch and verify a cylinder group.
3002  */
3003 int
3004 ffs_getcg(struct fs *fs,
3005 	struct vnode *devvp,
3006 	uint64_t cg,
3007 	int flags,
3008 	struct buf **bpp,
3009 	struct cg **cgpp)
3010 {
3011 	struct buf *bp;
3012 	struct cg *cgp;
3013 	struct mount *mp;
3014 	const struct statfs *sfs;
3015 	daddr_t blkno;
3016 	int error;
3017 
3018 	*bpp = NULL;
3019 	*cgpp = NULL;
3020 	if ((fs->fs_metackhash & CK_CYLGRP) != 0)
3021 		flags |= GB_CKHASH;
3022 	if (devvp->v_type == VCHR) {
3023 		blkno = fsbtodb(fs, cgtod(fs, cg));
3024 		mp = devvp->v_rdev->si_mountpt;
3025 	} else {
3026 		blkno = fragstoblks(fs, cgtod(fs, cg));
3027 		mp = devvp->v_mount;
3028 	}
3029 	error = breadn_flags(devvp, blkno, blkno, (int)fs->fs_cgsize, NULL,
3030 	    NULL, 0, NOCRED, flags, ffs_ckhash_cg, &bp);
3031 	if (error != 0)
3032 		return (error);
3033 	cgp = (struct cg *)bp->b_data;
3034 	if ((fs->fs_metackhash & CK_CYLGRP) != 0 &&
3035 	    (bp->b_flags & B_CKHASH) != 0 &&
3036 	    cgp->cg_ckhash != bp->b_ckhash) {
3037 		if (ppsratecheck(&VFSTOUFS(mp)->um_last_integritymsg,
3038 		    &VFSTOUFS(mp)->um_secs_integritymsg, 1)) {
3039 			sfs = &mp->mnt_stat;
3040 			printf("UFS %s%s (%s) cylinder checkhash failed: "
3041 			    "cg %ju, cgp: 0x%x != bp: 0x%jx\n",
3042 			    devvp->v_type == VCHR ? "" : "snapshot of ",
3043 			    sfs->f_mntfromname, sfs->f_mntonname, (intmax_t)cg,
3044 			    cgp->cg_ckhash, (uintmax_t)bp->b_ckhash);
3045 		}
3046 		bp->b_flags &= ~B_CKHASH;
3047 		bp->b_flags |= B_INVAL | B_NOCACHE;
3048 		brelse(bp);
3049 		return (EINTEGRITY);
3050 	}
3051 	if (!cg_chkmagic(cgp) || cgp->cg_cgx != cg) {
3052 		if (ppsratecheck(&VFSTOUFS(mp)->um_last_integritymsg,
3053 		    &VFSTOUFS(mp)->um_secs_integritymsg, 1)) {
3054 			sfs = &mp->mnt_stat;
3055 			printf("UFS %s%s (%s)",
3056 			    devvp->v_type == VCHR ? "" : "snapshot of ",
3057 			    sfs->f_mntfromname, sfs->f_mntonname);
3058 			if (!cg_chkmagic(cgp))
3059 				printf(" cg %ju: bad magic number 0x%x should "
3060 				    "be 0x%x\n", (intmax_t)cg, cgp->cg_magic,
3061 				    CG_MAGIC);
3062 			else
3063 				printf(": wrong cylinder group cg %ju != "
3064 				    "cgx %u\n", (intmax_t)cg, cgp->cg_cgx);
3065 		}
3066 		bp->b_flags &= ~B_CKHASH;
3067 		bp->b_flags |= B_INVAL | B_NOCACHE;
3068 		brelse(bp);
3069 		return (EINTEGRITY);
3070 	}
3071 	bp->b_flags &= ~B_CKHASH;
3072 	bp->b_xflags |= BX_BKGRDWRITE;
3073 	/*
3074 	 * If we are using check hashes on the cylinder group then we want
3075 	 * to limit changing the cylinder group time to when we are actually
3076 	 * going to write it to disk so that its check hash remains correct
3077 	 * in memory. If the CK_CYLGRP flag is set the time is updated in
3078 	 * ffs_bufwrite() as the buffer is queued for writing. Otherwise we
3079 	 * update the time here as we have done historically.
3080 	 */
3081 	if ((fs->fs_metackhash & CK_CYLGRP) != 0)
3082 		bp->b_xflags |= BX_CYLGRP;
3083 	else
3084 		cgp->cg_old_time = cgp->cg_time = time_second;
3085 	*bpp = bp;
3086 	*cgpp = cgp;
3087 	return (0);
3088 }
3089 
3090 static void
3091 ffs_ckhash_cg(struct buf *bp)
3092 {
3093 	uint32_t ckhash;
3094 	struct cg *cgp;
3095 
3096 	cgp = (struct cg *)bp->b_data;
3097 	ckhash = cgp->cg_ckhash;
3098 	cgp->cg_ckhash = 0;
3099 	bp->b_ckhash = calculate_crc32c(~0L, bp->b_data, bp->b_bcount);
3100 	cgp->cg_ckhash = ckhash;
3101 }
3102 
3103 /*
3104  * Called when a cylinder group read has failed. If an integrity check
3105  * is the cause of failure then the cylinder group will not be usable
3106  * until the filesystem has been unmounted and fsck has been run to
3107  * repair it. To avoid future attempts to allocate resources from the
3108  * cylinder group, its available resources are set to zero in the
3109  * superblock summary information. Since it will appear to have no
3110  * resources available, no further calls will be made to allocate
3111  * resources from it. When resources are freed to the cylinder group
3112  * the resource free routines will find the cylinder group unusable so
3113  * the resource will simply be discarded and thus will not show up in
3114  * the superblock summary information until they are recovered by fsck.
3115  */
3116 static void
3117 ffs_checkcgintegrity(struct fs *fs,
3118 	uint64_t cg,
3119 	int error)
3120 {
3121 
3122 	if (error != EINTEGRITY)
3123 		return;
3124 	fs->fs_cstotal.cs_nffree -= fs->fs_cs(fs, cg).cs_nffree;
3125 	fs->fs_cs(fs, cg).cs_nffree = 0;
3126 	fs->fs_cstotal.cs_nbfree -= fs->fs_cs(fs, cg).cs_nbfree;
3127 	fs->fs_cs(fs, cg).cs_nbfree = 0;
3128 	fs->fs_cstotal.cs_nifree -= fs->fs_cs(fs, cg).cs_nifree;
3129 	fs->fs_cs(fs, cg).cs_nifree = 0;
3130 	fs->fs_maxcluster[cg] = 0;
3131 	fs->fs_flags |= FS_NEEDSFSCK;
3132 	fs->fs_fmod = 1;
3133 }
3134 
3135 /*
3136  * Fserr prints the name of a filesystem with an error diagnostic.
3137  *
3138  * The form of the error message is:
3139  *	fs: error message
3140  */
3141 void
3142 ffs_fserr(struct fs *fs,
3143 	ino_t inum,
3144 	char *cp)
3145 {
3146 	struct thread *td = curthread;	/* XXX */
3147 	struct proc *p = td->td_proc;
3148 
3149 	log(LOG_ERR, "pid %d (%s), uid %d inumber %ju on %s: %s\n",
3150 	    p->p_pid, p->p_comm, td->td_ucred->cr_uid, (uintmax_t)inum,
3151 	    fs->fs_fsmnt, cp);
3152 }
3153 
3154 /*
3155  * This function provides the capability for the fsck program to
3156  * update an active filesystem. Sixteen operations are provided:
3157  *
3158  * adjrefcnt(inode, amt) - adjusts the reference count on the
3159  *	specified inode by the specified amount. Under normal
3160  *	operation the count should always go down. Decrementing
3161  *	the count to zero will cause the inode to be freed.
3162  * adjblkcnt(inode, amt) - adjust the number of blocks used by the
3163  *	inode by the specified amount.
3164  * adjdepth(inode, amt) - adjust the depth of the specified directory
3165  *	inode by the specified amount.
3166  * setsize(inode, size) - set the size of the inode to the
3167  *	specified size.
3168  * adjndir, adjbfree, adjifree, adjffree, adjnumclusters(amt) -
3169  *	adjust the superblock summary.
3170  * freedirs(inode, count) - directory inodes [inode..inode + count - 1]
3171  *	are marked as free. Inodes should never have to be marked
3172  *	as in use.
3173  * freefiles(inode, count) - file inodes [inode..inode + count - 1]
3174  *	are marked as free. Inodes should never have to be marked
3175  *	as in use.
3176  * freeblks(blockno, size) - blocks [blockno..blockno + size - 1]
3177  *	are marked as free. Blocks should never have to be marked
3178  *	as in use.
3179  * setflags(flags, set/clear) - the fs_flags field has the specified
3180  *	flags set (second parameter +1) or cleared (second parameter -1).
3181  * setcwd(dirinode) - set the current directory to dirinode in the
3182  *	filesystem associated with the snapshot.
3183  * setdotdot(oldvalue, newvalue) - Verify that the inode number for ".."
3184  *	in the current directory is oldvalue then change it to newvalue.
3185  * unlink(nameptr, oldvalue) - Verify that the inode number associated
3186  *	with nameptr in the current directory is oldvalue then unlink it.
3187  */
3188 
3189 static int sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS);
3190 
3191 SYSCTL_PROC(_vfs_ffs, FFS_ADJ_REFCNT, adjrefcnt,
3192     CTLFLAG_WR | CTLTYPE_STRUCT | CTLFLAG_NEEDGIANT,
3193     0, 0, sysctl_ffs_fsck, "S,fsck",
3194     "Adjust Inode Reference Count");
3195 
3196 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_BLKCNT, adjblkcnt,
3197     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3198     "Adjust Inode Used Blocks Count");
3199 
3200 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_DEPTH, adjdepth,
3201     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3202     "Adjust Directory Inode Depth");
3203 
3204 static SYSCTL_NODE(_vfs_ffs, FFS_SET_SIZE, setsize,
3205     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3206     "Set the inode size");
3207 
3208 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_NDIR, adjndir,
3209     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3210     "Adjust number of directories");
3211 
3212 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_NBFREE, adjnbfree,
3213     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3214     "Adjust number of free blocks");
3215 
3216 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_NIFREE, adjnifree,
3217     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3218     "Adjust number of free inodes");
3219 
3220 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_NFFREE, adjnffree,
3221     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3222     "Adjust number of free frags");
3223 
3224 static SYSCTL_NODE(_vfs_ffs, FFS_ADJ_NUMCLUSTERS, adjnumclusters,
3225     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3226     "Adjust number of free clusters");
3227 
3228 static SYSCTL_NODE(_vfs_ffs, FFS_DIR_FREE, freedirs,
3229     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3230     "Free Range of Directory Inodes");
3231 
3232 static SYSCTL_NODE(_vfs_ffs, FFS_FILE_FREE, freefiles,
3233     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3234     "Free Range of File Inodes");
3235 
3236 static SYSCTL_NODE(_vfs_ffs, FFS_BLK_FREE, freeblks,
3237     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3238     "Free Range of Blocks");
3239 
3240 static SYSCTL_NODE(_vfs_ffs, FFS_SET_FLAGS, setflags,
3241     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3242     "Change Filesystem Flags");
3243 
3244 static SYSCTL_NODE(_vfs_ffs, FFS_SET_CWD, setcwd,
3245     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3246     "Set Current Working Directory");
3247 
3248 static SYSCTL_NODE(_vfs_ffs, FFS_SET_DOTDOT, setdotdot,
3249     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3250     "Change Value of .. Entry");
3251 
3252 static SYSCTL_NODE(_vfs_ffs, FFS_UNLINK, unlink,
3253     CTLFLAG_WR | CTLFLAG_NEEDGIANT, sysctl_ffs_fsck,
3254     "Unlink a Duplicate Name");
3255 
3256 #ifdef DIAGNOSTIC
3257 static int fsckcmds = 0;
3258 SYSCTL_INT(_debug, OID_AUTO, ffs_fsckcmds, CTLFLAG_RW, &fsckcmds, 0,
3259 	"print out fsck_ffs-based filesystem update commands");
3260 #endif /* DIAGNOSTIC */
3261 
3262 static int
3263 sysctl_ffs_fsck(SYSCTL_HANDLER_ARGS)
3264 {
3265 	struct thread *td = curthread;
3266 	struct fsck_cmd cmd;
3267 	struct ufsmount *ump;
3268 	struct vnode *vp, *dvp, *fdvp;
3269 	struct inode *ip, *dp;
3270 	struct mount *mp;
3271 	struct fs *fs;
3272 	struct pwd *pwd;
3273 	ufs2_daddr_t blkno;
3274 	long blkcnt, blksize;
3275 	uint64_t key;
3276 	struct file *fp;
3277 	cap_rights_t rights;
3278 	int filetype, error;
3279 
3280 	if (req->newptr == NULL || req->newlen > sizeof(cmd))
3281 		return (EBADRPC);
3282 	if ((error = SYSCTL_IN(req, &cmd, sizeof(cmd))) != 0)
3283 		return (error);
3284 	if (cmd.version != FFS_CMD_VERSION)
3285 		return (ERPCMISMATCH);
3286 	if ((error = getvnode(td, cmd.handle,
3287 	    cap_rights_init_one(&rights, CAP_FSCK), &fp)) != 0)
3288 		return (error);
3289 	vp = fp->f_vnode;
3290 	if (vp->v_type != VREG && vp->v_type != VDIR) {
3291 		fdrop(fp, td);
3292 		return (EINVAL);
3293 	}
3294 	vn_start_write(vp, &mp, V_WAIT);
3295 	if (mp == NULL ||
3296 	    strncmp(mp->mnt_stat.f_fstypename, "ufs", MFSNAMELEN)) {
3297 		vn_finished_write(mp);
3298 		fdrop(fp, td);
3299 		return (EINVAL);
3300 	}
3301 	ump = VFSTOUFS(mp);
3302 	if (mp->mnt_flag & MNT_RDONLY) {
3303 		vn_finished_write(mp);
3304 		fdrop(fp, td);
3305 		return (EROFS);
3306 	}
3307 	fs = ump->um_fs;
3308 	filetype = IFREG;
3309 
3310 	switch (oidp->oid_number) {
3311 	case FFS_SET_FLAGS:
3312 #ifdef DIAGNOSTIC
3313 		if (fsckcmds)
3314 			printf("%s: %s flags\n", mp->mnt_stat.f_mntonname,
3315 			    cmd.size > 0 ? "set" : "clear");
3316 #endif /* DIAGNOSTIC */
3317 		if (cmd.size > 0)
3318 			fs->fs_flags |= (long)cmd.value;
3319 		else
3320 			fs->fs_flags &= ~(long)cmd.value;
3321 		break;
3322 
3323 	case FFS_ADJ_REFCNT:
3324 #ifdef DIAGNOSTIC
3325 		if (fsckcmds) {
3326 			printf("%s: adjust inode %jd link count by %jd\n",
3327 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value,
3328 			    (intmax_t)cmd.size);
3329 		}
3330 #endif /* DIAGNOSTIC */
3331 		if ((error = ffs_vget(mp, (ino_t)cmd.value, LK_EXCLUSIVE, &vp)))
3332 			break;
3333 		ip = VTOI(vp);
3334 		ip->i_nlink += cmd.size;
3335 		DIP_SET(ip, i_nlink, ip->i_nlink);
3336 		ip->i_effnlink += cmd.size;
3337 		UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_MODIFIED);
3338 		error = ffs_update(vp, 1);
3339 		if (DOINGSOFTDEP(vp))
3340 			softdep_change_linkcnt(ip);
3341 		vput(vp);
3342 		break;
3343 
3344 	case FFS_ADJ_BLKCNT:
3345 #ifdef DIAGNOSTIC
3346 		if (fsckcmds) {
3347 			printf("%s: adjust inode %jd block count by %jd\n",
3348 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value,
3349 			    (intmax_t)cmd.size);
3350 		}
3351 #endif /* DIAGNOSTIC */
3352 		if ((error = ffs_vget(mp, (ino_t)cmd.value, LK_EXCLUSIVE, &vp)))
3353 			break;
3354 		ip = VTOI(vp);
3355 		DIP_SET(ip, i_blocks, DIP(ip, i_blocks) + cmd.size);
3356 		UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_MODIFIED);
3357 		error = ffs_update(vp, 1);
3358 		vput(vp);
3359 		break;
3360 
3361 	case FFS_ADJ_DEPTH:
3362 #ifdef DIAGNOSTIC
3363 		if (fsckcmds) {
3364 			printf("%s: adjust directory inode %jd depth by %jd\n",
3365 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value,
3366 			    (intmax_t)cmd.size);
3367 		}
3368 #endif /* DIAGNOSTIC */
3369 		if ((error = ffs_vget(mp, (ino_t)cmd.value, LK_EXCLUSIVE, &vp)))
3370 			break;
3371 		if (vp->v_type != VDIR) {
3372 			vput(vp);
3373 			error = ENOTDIR;
3374 			break;
3375 		}
3376 		ip = VTOI(vp);
3377 		DIP_SET(ip, i_dirdepth, DIP(ip, i_dirdepth) + cmd.size);
3378 		UFS_INODE_SET_FLAG(ip, IN_CHANGE | IN_MODIFIED);
3379 		error = ffs_update(vp, 1);
3380 		vput(vp);
3381 		break;
3382 
3383 	case FFS_SET_SIZE:
3384 #ifdef DIAGNOSTIC
3385 		if (fsckcmds) {
3386 			printf("%s: set inode %jd size to %jd\n",
3387 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value,
3388 			    (intmax_t)cmd.size);
3389 		}
3390 #endif /* DIAGNOSTIC */
3391 		if ((error = ffs_vget(mp, (ino_t)cmd.value, LK_EXCLUSIVE, &vp)))
3392 			break;
3393 		ip = VTOI(vp);
3394 		DIP_SET(ip, i_size, cmd.size);
3395 		UFS_INODE_SET_FLAG(ip, IN_SIZEMOD | IN_CHANGE | IN_MODIFIED);
3396 		error = ffs_update(vp, 1);
3397 		vput(vp);
3398 		break;
3399 
3400 	case FFS_DIR_FREE:
3401 		filetype = IFDIR;
3402 		/* fall through */
3403 
3404 	case FFS_FILE_FREE:
3405 #ifdef DIAGNOSTIC
3406 		if (fsckcmds) {
3407 			if (cmd.size == 1)
3408 				printf("%s: free %s inode %ju\n",
3409 				    mp->mnt_stat.f_mntonname,
3410 				    filetype == IFDIR ? "directory" : "file",
3411 				    (uintmax_t)cmd.value);
3412 			else
3413 				printf("%s: free %s inodes %ju-%ju\n",
3414 				    mp->mnt_stat.f_mntonname,
3415 				    filetype == IFDIR ? "directory" : "file",
3416 				    (uintmax_t)cmd.value,
3417 				    (uintmax_t)(cmd.value + cmd.size - 1));
3418 		}
3419 #endif /* DIAGNOSTIC */
3420 		while (cmd.size > 0) {
3421 			if ((error = ffs_freefile(ump, fs, ump->um_devvp,
3422 			    cmd.value, filetype, NULL)))
3423 				break;
3424 			cmd.size -= 1;
3425 			cmd.value += 1;
3426 		}
3427 		break;
3428 
3429 	case FFS_BLK_FREE:
3430 #ifdef DIAGNOSTIC
3431 		if (fsckcmds) {
3432 			if (cmd.size == 1)
3433 				printf("%s: free block %jd\n",
3434 				    mp->mnt_stat.f_mntonname,
3435 				    (intmax_t)cmd.value);
3436 			else
3437 				printf("%s: free blocks %jd-%jd\n",
3438 				    mp->mnt_stat.f_mntonname,
3439 				    (intmax_t)cmd.value,
3440 				    (intmax_t)cmd.value + cmd.size - 1);
3441 		}
3442 #endif /* DIAGNOSTIC */
3443 		blkno = cmd.value;
3444 		blkcnt = cmd.size;
3445 		blksize = fs->fs_frag - (blkno % fs->fs_frag);
3446 		key = ffs_blkrelease_start(ump, ump->um_devvp, UFS_ROOTINO);
3447 		while (blkcnt > 0) {
3448 			if (blkcnt < blksize)
3449 				blksize = blkcnt;
3450 			ffs_blkfree(ump, fs, ump->um_devvp, blkno,
3451 			    blksize * fs->fs_fsize, UFS_ROOTINO,
3452 			    VDIR, NULL, key);
3453 			blkno += blksize;
3454 			blkcnt -= blksize;
3455 			blksize = fs->fs_frag;
3456 		}
3457 		ffs_blkrelease_finish(ump, key);
3458 		break;
3459 
3460 	/*
3461 	 * Adjust superblock summaries.  fsck(8) is expected to
3462 	 * submit deltas when necessary.
3463 	 */
3464 	case FFS_ADJ_NDIR:
3465 #ifdef DIAGNOSTIC
3466 		if (fsckcmds) {
3467 			printf("%s: adjust number of directories by %jd\n",
3468 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value);
3469 		}
3470 #endif /* DIAGNOSTIC */
3471 		fs->fs_cstotal.cs_ndir += cmd.value;
3472 		break;
3473 
3474 	case FFS_ADJ_NBFREE:
3475 #ifdef DIAGNOSTIC
3476 		if (fsckcmds) {
3477 			printf("%s: adjust number of free blocks by %+jd\n",
3478 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value);
3479 		}
3480 #endif /* DIAGNOSTIC */
3481 		fs->fs_cstotal.cs_nbfree += cmd.value;
3482 		break;
3483 
3484 	case FFS_ADJ_NIFREE:
3485 #ifdef DIAGNOSTIC
3486 		if (fsckcmds) {
3487 			printf("%s: adjust number of free inodes by %+jd\n",
3488 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value);
3489 		}
3490 #endif /* DIAGNOSTIC */
3491 		fs->fs_cstotal.cs_nifree += cmd.value;
3492 		break;
3493 
3494 	case FFS_ADJ_NFFREE:
3495 #ifdef DIAGNOSTIC
3496 		if (fsckcmds) {
3497 			printf("%s: adjust number of free frags by %+jd\n",
3498 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value);
3499 		}
3500 #endif /* DIAGNOSTIC */
3501 		fs->fs_cstotal.cs_nffree += cmd.value;
3502 		break;
3503 
3504 	case FFS_ADJ_NUMCLUSTERS:
3505 #ifdef DIAGNOSTIC
3506 		if (fsckcmds) {
3507 			printf("%s: adjust number of free clusters by %+jd\n",
3508 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value);
3509 		}
3510 #endif /* DIAGNOSTIC */
3511 		fs->fs_cstotal.cs_numclusters += cmd.value;
3512 		break;
3513 
3514 	case FFS_SET_CWD:
3515 #ifdef DIAGNOSTIC
3516 		if (fsckcmds) {
3517 			printf("%s: set current directory to inode %jd\n",
3518 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value);
3519 		}
3520 #endif /* DIAGNOSTIC */
3521 		if ((error = ffs_vget(mp, (ino_t)cmd.value, LK_SHARED, &vp)))
3522 			break;
3523 		AUDIT_ARG_VNODE1(vp);
3524 		if ((error = change_dir(vp, td)) != 0) {
3525 			vput(vp);
3526 			break;
3527 		}
3528 		VOP_UNLOCK(vp);
3529 		pwd_chdir(td, vp);
3530 		break;
3531 
3532 	case FFS_SET_DOTDOT:
3533 #ifdef DIAGNOSTIC
3534 		if (fsckcmds) {
3535 			printf("%s: change .. in cwd from %jd to %jd\n",
3536 			    mp->mnt_stat.f_mntonname, (intmax_t)cmd.value,
3537 			    (intmax_t)cmd.size);
3538 		}
3539 #endif /* DIAGNOSTIC */
3540 		/*
3541 		 * First we have to get and lock the parent directory
3542 		 * to which ".." points.
3543 		 */
3544 		error = ffs_vget(mp, (ino_t)cmd.value, LK_EXCLUSIVE, &fdvp);
3545 		if (error)
3546 			break;
3547 		/*
3548 		 * Now we get and lock the child directory containing "..".
3549 		 */
3550 		pwd = pwd_hold(td);
3551 		dvp = pwd->pwd_cdir;
3552 		if ((error = vget(dvp, LK_EXCLUSIVE)) != 0) {
3553 			vput(fdvp);
3554 			pwd_drop(pwd);
3555 			break;
3556 		}
3557 		dp = VTOI(dvp);
3558 		SET_I_OFFSET(dp, 12);	/* XXX mastertemplate.dot_reclen */
3559 		error = ufs_dirrewrite(dp, VTOI(fdvp), (ino_t)cmd.size,
3560 		    DT_DIR, 0);
3561 		cache_purge(fdvp);
3562 		cache_purge(dvp);
3563 		vput(dvp);
3564 		vput(fdvp);
3565 		pwd_drop(pwd);
3566 		break;
3567 
3568 	case FFS_UNLINK:
3569 #ifdef DIAGNOSTIC
3570 		if (fsckcmds) {
3571 			char buf[32];
3572 
3573 			if (copyinstr((char *)(intptr_t)cmd.value, buf,32,NULL))
3574 				strncpy(buf, "Name_too_long", 32);
3575 			printf("%s: unlink %s (inode %jd)\n",
3576 			    mp->mnt_stat.f_mntonname, buf, (intmax_t)cmd.size);
3577 		}
3578 #endif /* DIAGNOSTIC */
3579 		/*
3580 		 * kern_funlinkat will do its own start/finish writes and
3581 		 * they do not nest, so drop ours here. Setting mp == NULL
3582 		 * indicates that vn_finished_write is not needed down below.
3583 		 */
3584 		vn_finished_write(mp);
3585 		mp = NULL;
3586 		error = kern_funlinkat(td, AT_FDCWD,
3587 		    (char *)(intptr_t)cmd.value, FD_NONE, UIO_USERSPACE,
3588 		    0, (ino_t)cmd.size);
3589 		break;
3590 
3591 	default:
3592 #ifdef DIAGNOSTIC
3593 		if (fsckcmds) {
3594 			printf("Invalid request %d from fsck\n",
3595 			    oidp->oid_number);
3596 		}
3597 #endif /* DIAGNOSTIC */
3598 		error = EINVAL;
3599 		break;
3600 	}
3601 	fdrop(fp, td);
3602 	vn_finished_write(mp);
3603 	return (error);
3604 }
3605