xref: /freebsd/sys/ufs/ffs/ffs_vfsops.c (revision 7a8d62cd046942ab34fcf282ecbbb0747a08a4ee)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1989, 1991, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)ffs_vfsops.c	8.31 (Berkeley) 5/20/95
32  */
33 
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
36 
37 #include "opt_quota.h"
38 #include "opt_ufs.h"
39 #include "opt_ffs.h"
40 #include "opt_ddb.h"
41 
42 #include <sys/param.h>
43 #include <sys/gsb_crc32.h>
44 #include <sys/systm.h>
45 #include <sys/namei.h>
46 #include <sys/priv.h>
47 #include <sys/proc.h>
48 #include <sys/taskqueue.h>
49 #include <sys/kernel.h>
50 #include <sys/ktr.h>
51 #include <sys/vnode.h>
52 #include <sys/mount.h>
53 #include <sys/bio.h>
54 #include <sys/buf.h>
55 #include <sys/conf.h>
56 #include <sys/fcntl.h>
57 #include <sys/ioccom.h>
58 #include <sys/malloc.h>
59 #include <sys/mutex.h>
60 #include <sys/rwlock.h>
61 #include <sys/sysctl.h>
62 #include <sys/vmmeter.h>
63 
64 #include <security/mac/mac_framework.h>
65 
66 #include <ufs/ufs/dir.h>
67 #include <ufs/ufs/extattr.h>
68 #include <ufs/ufs/gjournal.h>
69 #include <ufs/ufs/quota.h>
70 #include <ufs/ufs/ufsmount.h>
71 #include <ufs/ufs/inode.h>
72 #include <ufs/ufs/ufs_extern.h>
73 
74 #include <ufs/ffs/fs.h>
75 #include <ufs/ffs/ffs_extern.h>
76 
77 #include <vm/vm.h>
78 #include <vm/uma.h>
79 #include <vm/vm_page.h>
80 
81 #include <geom/geom.h>
82 #include <geom/geom_vfs.h>
83 
84 #include <ddb/ddb.h>
85 
86 static uma_zone_t uma_inode, uma_ufs1, uma_ufs2;
87 VFS_SMR_DECLARE;
88 
89 static int	ffs_mountfs(struct vnode *, struct mount *, struct thread *);
90 static void	ffs_oldfscompat_read(struct fs *, struct ufsmount *,
91 		    ufs2_daddr_t);
92 static void	ffs_ifree(struct ufsmount *ump, struct inode *ip);
93 static int	ffs_sync_lazy(struct mount *mp);
94 static int	ffs_use_bread(void *devfd, off_t loc, void **bufp, int size);
95 static int	ffs_use_bwrite(void *devfd, off_t loc, void *buf, int size);
96 
97 static vfs_init_t ffs_init;
98 static vfs_uninit_t ffs_uninit;
99 static vfs_extattrctl_t ffs_extattrctl;
100 static vfs_cmount_t ffs_cmount;
101 static vfs_unmount_t ffs_unmount;
102 static vfs_mount_t ffs_mount;
103 static vfs_statfs_t ffs_statfs;
104 static vfs_fhtovp_t ffs_fhtovp;
105 static vfs_sync_t ffs_sync;
106 
107 static struct vfsops ufs_vfsops = {
108 	.vfs_extattrctl =	ffs_extattrctl,
109 	.vfs_fhtovp =		ffs_fhtovp,
110 	.vfs_init =		ffs_init,
111 	.vfs_mount =		ffs_mount,
112 	.vfs_cmount =		ffs_cmount,
113 	.vfs_quotactl =		ufs_quotactl,
114 	.vfs_root =		vfs_cache_root,
115 	.vfs_cachedroot =	ufs_root,
116 	.vfs_statfs =		ffs_statfs,
117 	.vfs_sync =		ffs_sync,
118 	.vfs_uninit =		ffs_uninit,
119 	.vfs_unmount =		ffs_unmount,
120 	.vfs_vget =		ffs_vget,
121 	.vfs_susp_clean =	process_deferred_inactive,
122 };
123 
124 VFS_SET(ufs_vfsops, ufs, 0);
125 MODULE_VERSION(ufs, 1);
126 
127 static b_strategy_t ffs_geom_strategy;
128 static b_write_t ffs_bufwrite;
129 
130 static struct buf_ops ffs_ops = {
131 	.bop_name =	"FFS",
132 	.bop_write =	ffs_bufwrite,
133 	.bop_strategy =	ffs_geom_strategy,
134 	.bop_sync =	bufsync,
135 #ifdef NO_FFS_SNAPSHOT
136 	.bop_bdflush =	bufbdflush,
137 #else
138 	.bop_bdflush =	ffs_bdflush,
139 #endif
140 };
141 
142 /*
143  * Note that userquota and groupquota options are not currently used
144  * by UFS/FFS code and generally mount(8) does not pass those options
145  * from userland, but they can be passed by loader(8) via
146  * vfs.root.mountfrom.options.
147  */
148 static const char *ffs_opts[] = { "acls", "async", "noatime", "noclusterr",
149     "noclusterw", "noexec", "export", "force", "from", "groupquota",
150     "multilabel", "nfsv4acls", "snapshot", "nosuid", "suiddir",
151     "nosymfollow", "sync", "union", "userquota", "untrusted", NULL };
152 
153 static int ffs_enxio_enable = 1;
154 SYSCTL_DECL(_vfs_ffs);
155 SYSCTL_INT(_vfs_ffs, OID_AUTO, enxio_enable, CTLFLAG_RWTUN,
156     &ffs_enxio_enable, 0,
157     "enable mapping of other disk I/O errors to ENXIO");
158 
159 /*
160  * Return buffer with the contents of block "offset" from the beginning of
161  * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
162  * remaining space in the directory.
163  */
164 static int
165 ffs_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp)
166 {
167 	struct inode *ip;
168 	struct fs *fs;
169 	struct buf *bp;
170 	ufs_lbn_t lbn;
171 	int bsize, error;
172 
173 	ip = VTOI(vp);
174 	fs = ITOFS(ip);
175 	lbn = lblkno(fs, offset);
176 	bsize = blksize(fs, ip, lbn);
177 
178 	*bpp = NULL;
179 	error = bread(vp, lbn, bsize, NOCRED, &bp);
180 	if (error) {
181 		return (error);
182 	}
183 	if (res)
184 		*res = (char *)bp->b_data + blkoff(fs, offset);
185 	*bpp = bp;
186 	return (0);
187 }
188 
189 /*
190  * Load up the contents of an inode and copy the appropriate pieces
191  * to the incore copy.
192  */
193 static int
194 ffs_load_inode(struct buf *bp, struct inode *ip, struct fs *fs, ino_t ino)
195 {
196 	struct ufs1_dinode *dip1;
197 	struct ufs2_dinode *dip2;
198 	int error;
199 
200 	if (I_IS_UFS1(ip)) {
201 		dip1 = ip->i_din1;
202 		*dip1 =
203 		    *((struct ufs1_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
204 		ip->i_mode = dip1->di_mode;
205 		ip->i_nlink = dip1->di_nlink;
206 		ip->i_effnlink = dip1->di_nlink;
207 		ip->i_size = dip1->di_size;
208 		ip->i_flags = dip1->di_flags;
209 		ip->i_gen = dip1->di_gen;
210 		ip->i_uid = dip1->di_uid;
211 		ip->i_gid = dip1->di_gid;
212 		return (0);
213 	}
214 	dip2 = ((struct ufs2_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
215 	if ((error = ffs_verify_dinode_ckhash(fs, dip2)) != 0 &&
216 	    !ffs_fsfail_cleanup(ITOUMP(ip), error)) {
217 		printf("%s: inode %jd: check-hash failed\n", fs->fs_fsmnt,
218 		    (intmax_t)ino);
219 		return (error);
220 	}
221 	*ip->i_din2 = *dip2;
222 	dip2 = ip->i_din2;
223 	ip->i_mode = dip2->di_mode;
224 	ip->i_nlink = dip2->di_nlink;
225 	ip->i_effnlink = dip2->di_nlink;
226 	ip->i_size = dip2->di_size;
227 	ip->i_flags = dip2->di_flags;
228 	ip->i_gen = dip2->di_gen;
229 	ip->i_uid = dip2->di_uid;
230 	ip->i_gid = dip2->di_gid;
231 	return (0);
232 }
233 
234 /*
235  * Verify that a filesystem block number is a valid data block.
236  * This routine is only called on untrusted filesystems.
237  */
238 static int
239 ffs_check_blkno(struct mount *mp, ino_t inum, ufs2_daddr_t daddr, int blksize)
240 {
241 	struct fs *fs;
242 	struct ufsmount *ump;
243 	ufs2_daddr_t end_daddr;
244 	int cg, havemtx;
245 
246 	KASSERT((mp->mnt_flag & MNT_UNTRUSTED) != 0,
247 	    ("ffs_check_blkno called on a trusted file system"));
248 	ump = VFSTOUFS(mp);
249 	fs = ump->um_fs;
250 	cg = dtog(fs, daddr);
251 	end_daddr = daddr + numfrags(fs, blksize);
252 	/*
253 	 * Verify that the block number is a valid data block. Also check
254 	 * that it does not point to an inode block or a superblock. Accept
255 	 * blocks that are unalloacted (0) or part of snapshot metadata
256 	 * (BLK_NOCOPY or BLK_SNAP).
257 	 *
258 	 * Thus, the block must be in a valid range for the filesystem and
259 	 * either in the space before a backup superblock (except the first
260 	 * cylinder group where that space is used by the bootstrap code) or
261 	 * after the inode blocks and before the end of the cylinder group.
262 	 */
263 	if ((uint64_t)daddr <= BLK_SNAP ||
264 	    ((uint64_t)end_daddr <= fs->fs_size &&
265 	    ((cg > 0 && end_daddr <= cgsblock(fs, cg)) ||
266 	    (daddr >= cgdmin(fs, cg) &&
267 	    end_daddr <= cgbase(fs, cg) + fs->fs_fpg))))
268 		return (0);
269 	if ((havemtx = mtx_owned(UFS_MTX(ump))) == 0)
270 		UFS_LOCK(ump);
271 	if (ppsratecheck(&ump->um_last_integritymsg,
272 	    &ump->um_secs_integritymsg, 1)) {
273 		UFS_UNLOCK(ump);
274 		uprintf("\n%s: inode %jd, out-of-range indirect block "
275 		    "number %jd\n", mp->mnt_stat.f_mntonname, inum, daddr);
276 		if (havemtx)
277 			UFS_LOCK(ump);
278 	} else if (!havemtx)
279 		UFS_UNLOCK(ump);
280 	return (EINTEGRITY);
281 }
282 
283 /*
284  * On first ENXIO error, initiate an asynchronous forcible unmount.
285  * Used to unmount filesystems whose underlying media has gone away.
286  *
287  * Return true if a cleanup is in progress.
288  */
289 int
290 ffs_fsfail_cleanup(struct ufsmount *ump, int error)
291 {
292 	int retval;
293 
294 	UFS_LOCK(ump);
295 	retval = ffs_fsfail_cleanup_locked(ump, error);
296 	UFS_UNLOCK(ump);
297 	return (retval);
298 }
299 
300 int
301 ffs_fsfail_cleanup_locked(struct ufsmount *ump, int error)
302 {
303 	mtx_assert(UFS_MTX(ump), MA_OWNED);
304 	if (error == ENXIO && (ump->um_flags & UM_FSFAIL_CLEANUP) == 0) {
305 		ump->um_flags |= UM_FSFAIL_CLEANUP;
306 		/*
307 		 * Queue an async forced unmount.
308 		 */
309 		vfs_ref(ump->um_mountp);
310 		dounmount(ump->um_mountp,
311 		    MNT_FORCE | MNT_RECURSE | MNT_DEFERRED, curthread);
312 		printf("UFS: forcibly unmounting %s from %s\n",
313 		    ump->um_mountp->mnt_stat.f_mntfromname,
314 		    ump->um_mountp->mnt_stat.f_mntonname);
315 	}
316 	return ((ump->um_flags & UM_FSFAIL_CLEANUP) != 0);
317 }
318 
319 /*
320  * Wrapper used during ENXIO cleanup to allocate empty buffers when
321  * the kernel is unable to read the real one. They are needed so that
322  * the soft updates code can use them to unwind its dependencies.
323  */
324 int
325 ffs_breadz(struct ufsmount *ump, struct vnode *vp, daddr_t lblkno,
326     daddr_t dblkno, int size, daddr_t *rablkno, int *rabsize, int cnt,
327     struct ucred *cred, int flags, void (*ckhashfunc)(struct buf *),
328     struct buf **bpp)
329 {
330 	int error;
331 
332 	flags |= GB_CVTENXIO;
333 	error = breadn_flags(vp, lblkno, dblkno, size, rablkno, rabsize, cnt,
334 	    cred, flags, ckhashfunc, bpp);
335 	if (error != 0 && ffs_fsfail_cleanup(ump, error)) {
336 		error = getblkx(vp, lblkno, dblkno, size, 0, 0, flags, bpp);
337 		KASSERT(error == 0, ("getblkx failed"));
338 		vfs_bio_bzero_buf(*bpp, 0, size);
339 	}
340 	return (error);
341 }
342 
343 static int
344 ffs_mount(struct mount *mp)
345 {
346 	struct vnode *devvp, *odevvp;
347 	struct thread *td;
348 	struct ufsmount *ump = NULL;
349 	struct fs *fs;
350 	int error, flags;
351 	int error1 __diagused;
352 	uint64_t mntorflags, saved_mnt_flag;
353 	accmode_t accmode;
354 	struct nameidata ndp;
355 	char *fspec;
356 	bool mounted_softdep;
357 
358 	td = curthread;
359 	if (vfs_filteropt(mp->mnt_optnew, ffs_opts))
360 		return (EINVAL);
361 	if (uma_inode == NULL) {
362 		uma_inode = uma_zcreate("FFS inode",
363 		    sizeof(struct inode), NULL, NULL, NULL, NULL,
364 		    UMA_ALIGN_PTR, 0);
365 		uma_ufs1 = uma_zcreate("FFS1 dinode",
366 		    sizeof(struct ufs1_dinode), NULL, NULL, NULL, NULL,
367 		    UMA_ALIGN_PTR, 0);
368 		uma_ufs2 = uma_zcreate("FFS2 dinode",
369 		    sizeof(struct ufs2_dinode), NULL, NULL, NULL, NULL,
370 		    UMA_ALIGN_PTR, 0);
371 		VFS_SMR_ZONE_SET(uma_inode);
372 	}
373 
374 	vfs_deleteopt(mp->mnt_optnew, "groupquota");
375 	vfs_deleteopt(mp->mnt_optnew, "userquota");
376 
377 	fspec = vfs_getopts(mp->mnt_optnew, "from", &error);
378 	if (error)
379 		return (error);
380 
381 	mntorflags = 0;
382 	if (vfs_getopt(mp->mnt_optnew, "untrusted", NULL, NULL) == 0)
383 		mntorflags |= MNT_UNTRUSTED;
384 
385 	if (vfs_getopt(mp->mnt_optnew, "acls", NULL, NULL) == 0)
386 		mntorflags |= MNT_ACLS;
387 
388 	if (vfs_getopt(mp->mnt_optnew, "snapshot", NULL, NULL) == 0) {
389 		mntorflags |= MNT_SNAPSHOT;
390 		/*
391 		 * Once we have set the MNT_SNAPSHOT flag, do not
392 		 * persist "snapshot" in the options list.
393 		 */
394 		vfs_deleteopt(mp->mnt_optnew, "snapshot");
395 		vfs_deleteopt(mp->mnt_opt, "snapshot");
396 	}
397 
398 	if (vfs_getopt(mp->mnt_optnew, "nfsv4acls", NULL, NULL) == 0) {
399 		if (mntorflags & MNT_ACLS) {
400 			vfs_mount_error(mp,
401 			    "\"acls\" and \"nfsv4acls\" options "
402 			    "are mutually exclusive");
403 			return (EINVAL);
404 		}
405 		mntorflags |= MNT_NFS4ACLS;
406 	}
407 
408 	MNT_ILOCK(mp);
409 	mp->mnt_kern_flag &= ~MNTK_FPLOOKUP;
410 	mp->mnt_flag |= mntorflags;
411 	MNT_IUNLOCK(mp);
412 
413 	/*
414 	 * If this is a snapshot request, take the snapshot.
415 	 */
416 	if (mp->mnt_flag & MNT_SNAPSHOT) {
417 		if ((mp->mnt_flag & MNT_UPDATE) == 0)
418 			return (EINVAL);
419 		return (ffs_snapshot(mp, fspec));
420 	}
421 
422 	/*
423 	 * Must not call namei() while owning busy ref.
424 	 */
425 	if (mp->mnt_flag & MNT_UPDATE)
426 		vfs_unbusy(mp);
427 
428 	/*
429 	 * Not an update, or updating the name: look up the name
430 	 * and verify that it refers to a sensible disk device.
431 	 */
432 	NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec);
433 	error = namei(&ndp);
434 	if ((mp->mnt_flag & MNT_UPDATE) != 0) {
435 		/*
436 		 * Unmount does not start if MNT_UPDATE is set.  Mount
437 		 * update busies mp before setting MNT_UPDATE.  We
438 		 * must be able to retain our busy ref successfully,
439 		 * without sleep.
440 		 */
441 		error1 = vfs_busy(mp, MBF_NOWAIT);
442 		MPASS(error1 == 0);
443 	}
444 	if (error != 0)
445 		return (error);
446 	NDFREE_PNBUF(&ndp);
447 	if (!vn_isdisk_error(ndp.ni_vp, &error)) {
448 		vput(ndp.ni_vp);
449 		return (error);
450 	}
451 
452 	/*
453 	 * If mount by non-root, then verify that user has necessary
454 	 * permissions on the device.
455 	 */
456 	accmode = VREAD;
457 	if ((mp->mnt_flag & MNT_RDONLY) == 0)
458 		accmode |= VWRITE;
459 	error = VOP_ACCESS(ndp.ni_vp, accmode, td->td_ucred, td);
460 	if (error)
461 		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
462 	if (error) {
463 		vput(ndp.ni_vp);
464 		return (error);
465 	}
466 
467 	/*
468 	 * New mount
469 	 *
470 	 * We need the name for the mount point (also used for
471 	 * "last mounted on") copied in. If an error occurs,
472 	 * the mount point is discarded by the upper level code.
473 	 * Note that vfs_mount_alloc() populates f_mntonname for us.
474 	 */
475 	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
476 		if ((error = ffs_mountfs(ndp.ni_vp, mp, td)) != 0) {
477 			vrele(ndp.ni_vp);
478 			return (error);
479 		}
480 	} else {
481 		/*
482 		 * When updating, check whether changing from read-only to
483 		 * read/write; if there is no device name, that's all we do.
484 		 */
485 		ump = VFSTOUFS(mp);
486 		fs = ump->um_fs;
487 		odevvp = ump->um_odevvp;
488 		devvp = ump->um_devvp;
489 
490 		/*
491 		 * If it's not the same vnode, or at least the same device
492 		 * then it's not correct.
493 		 */
494 		if (ndp.ni_vp->v_rdev != ump->um_odevvp->v_rdev)
495 			error = EINVAL; /* needs translation */
496 		vput(ndp.ni_vp);
497 		if (error)
498 			return (error);
499 		if (fs->fs_ronly == 0 &&
500 		    vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
501 			/*
502 			 * Flush any dirty data and suspend filesystem.
503 			 */
504 			if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0)
505 				return (error);
506 			error = vfs_write_suspend_umnt(mp);
507 			if (error != 0)
508 				return (error);
509 
510 			fs->fs_ronly = 1;
511 			if (MOUNTEDSOFTDEP(mp)) {
512 				MNT_ILOCK(mp);
513 				mp->mnt_flag &= ~MNT_SOFTDEP;
514 				MNT_IUNLOCK(mp);
515 				mounted_softdep = true;
516 			} else
517 				mounted_softdep = false;
518 
519 			/*
520 			 * Check for and optionally get rid of files open
521 			 * for writing.
522 			 */
523 			flags = WRITECLOSE;
524 			if (mp->mnt_flag & MNT_FORCE)
525 				flags |= FORCECLOSE;
526 			if (mounted_softdep) {
527 				error = softdep_flushfiles(mp, flags, td);
528 			} else {
529 				error = ffs_flushfiles(mp, flags, td);
530 			}
531 			if (error) {
532 				fs->fs_ronly = 0;
533 				if (mounted_softdep) {
534 					MNT_ILOCK(mp);
535 					mp->mnt_flag |= MNT_SOFTDEP;
536 					MNT_IUNLOCK(mp);
537 				}
538 				vfs_write_resume(mp, 0);
539 				return (error);
540 			}
541 
542 			if (fs->fs_pendingblocks != 0 ||
543 			    fs->fs_pendinginodes != 0) {
544 				printf("WARNING: %s Update error: blocks %jd "
545 				    "files %d\n", fs->fs_fsmnt,
546 				    (intmax_t)fs->fs_pendingblocks,
547 				    fs->fs_pendinginodes);
548 				fs->fs_pendingblocks = 0;
549 				fs->fs_pendinginodes = 0;
550 			}
551 			if ((fs->fs_flags & (FS_UNCLEAN | FS_NEEDSFSCK)) == 0)
552 				fs->fs_clean = 1;
553 			if ((error = ffs_sbupdate(ump, MNT_WAIT, 0)) != 0) {
554 				fs->fs_ronly = 0;
555 				fs->fs_clean = 0;
556 				if (mounted_softdep) {
557 					MNT_ILOCK(mp);
558 					mp->mnt_flag |= MNT_SOFTDEP;
559 					MNT_IUNLOCK(mp);
560 				}
561 				vfs_write_resume(mp, 0);
562 				return (error);
563 			}
564 			if (mounted_softdep)
565 				softdep_unmount(mp);
566 			g_topology_lock();
567 			/*
568 			 * Drop our write and exclusive access.
569 			 */
570 			g_access(ump->um_cp, 0, -1, -1);
571 			g_topology_unlock();
572 			MNT_ILOCK(mp);
573 			mp->mnt_flag |= MNT_RDONLY;
574 			MNT_IUNLOCK(mp);
575 			/*
576 			 * Allow the writers to note that filesystem
577 			 * is ro now.
578 			 */
579 			vfs_write_resume(mp, 0);
580 		}
581 		if ((mp->mnt_flag & MNT_RELOAD) &&
582 		    (error = ffs_reload(mp, 0)) != 0)
583 			return (error);
584 		if (fs->fs_ronly &&
585 		    !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
586 			/*
587 			 * If upgrade to read-write by non-root, then verify
588 			 * that user has necessary permissions on the device.
589 			 */
590 			vn_lock(odevvp, LK_EXCLUSIVE | LK_RETRY);
591 			error = VOP_ACCESS(odevvp, VREAD | VWRITE,
592 			    td->td_ucred, td);
593 			if (error)
594 				error = priv_check(td, PRIV_VFS_MOUNT_PERM);
595 			VOP_UNLOCK(odevvp);
596 			if (error) {
597 				return (error);
598 			}
599 			fs->fs_flags &= ~FS_UNCLEAN;
600 			if (fs->fs_clean == 0) {
601 				fs->fs_flags |= FS_UNCLEAN;
602 				if ((mp->mnt_flag & MNT_FORCE) ||
603 				    ((fs->fs_flags &
604 				     (FS_SUJ | FS_NEEDSFSCK)) == 0 &&
605 				     (fs->fs_flags & FS_DOSOFTDEP))) {
606 					printf("WARNING: %s was not properly "
607 					   "dismounted\n",
608 					   mp->mnt_stat.f_mntonname);
609 				} else {
610 					vfs_mount_error(mp,
611 					   "R/W mount of %s denied. %s.%s",
612 					   mp->mnt_stat.f_mntonname,
613 					   "Filesystem is not clean - run fsck",
614 					   (fs->fs_flags & FS_SUJ) == 0 ? "" :
615 					   " Forced mount will invalidate"
616 					   " journal contents");
617 					return (EPERM);
618 				}
619 			}
620 			g_topology_lock();
621 			/*
622 			 * Request exclusive write access.
623 			 */
624 			error = g_access(ump->um_cp, 0, 1, 1);
625 			g_topology_unlock();
626 			if (error)
627 				return (error);
628 			if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0)
629 				return (error);
630 			error = vfs_write_suspend_umnt(mp);
631 			if (error != 0)
632 				return (error);
633 			fs->fs_ronly = 0;
634 			MNT_ILOCK(mp);
635 			saved_mnt_flag = MNT_RDONLY;
636 			if (MOUNTEDSOFTDEP(mp) && (mp->mnt_flag &
637 			    MNT_ASYNC) != 0)
638 				saved_mnt_flag |= MNT_ASYNC;
639 			mp->mnt_flag &= ~saved_mnt_flag;
640 			MNT_IUNLOCK(mp);
641 			fs->fs_mtime = time_second;
642 			/* check to see if we need to start softdep */
643 			if ((fs->fs_flags & FS_DOSOFTDEP) &&
644 			    (error = softdep_mount(devvp, mp, fs, td->td_ucred))){
645 				fs->fs_ronly = 1;
646 				MNT_ILOCK(mp);
647 				mp->mnt_flag |= saved_mnt_flag;
648 				MNT_IUNLOCK(mp);
649 				vfs_write_resume(mp, 0);
650 				return (error);
651 			}
652 			fs->fs_clean = 0;
653 			if ((error = ffs_sbupdate(ump, MNT_WAIT, 0)) != 0) {
654 				fs->fs_ronly = 1;
655 				if ((fs->fs_flags & FS_DOSOFTDEP) != 0)
656 					softdep_unmount(mp);
657 				MNT_ILOCK(mp);
658 				mp->mnt_flag |= saved_mnt_flag;
659 				MNT_IUNLOCK(mp);
660 				vfs_write_resume(mp, 0);
661 				return (error);
662 			}
663 			if (fs->fs_snapinum[0] != 0)
664 				ffs_snapshot_mount(mp);
665 			vfs_write_resume(mp, 0);
666 		}
667 		/*
668 		 * Soft updates is incompatible with "async",
669 		 * so if we are doing softupdates stop the user
670 		 * from setting the async flag in an update.
671 		 * Softdep_mount() clears it in an initial mount
672 		 * or ro->rw remount.
673 		 */
674 		if (MOUNTEDSOFTDEP(mp)) {
675 			/* XXX: Reset too late ? */
676 			MNT_ILOCK(mp);
677 			mp->mnt_flag &= ~MNT_ASYNC;
678 			MNT_IUNLOCK(mp);
679 		}
680 		/*
681 		 * Keep MNT_ACLS flag if it is stored in superblock.
682 		 */
683 		if ((fs->fs_flags & FS_ACLS) != 0) {
684 			/* XXX: Set too late ? */
685 			MNT_ILOCK(mp);
686 			mp->mnt_flag |= MNT_ACLS;
687 			MNT_IUNLOCK(mp);
688 		}
689 
690 		if ((fs->fs_flags & FS_NFS4ACLS) != 0) {
691 			/* XXX: Set too late ? */
692 			MNT_ILOCK(mp);
693 			mp->mnt_flag |= MNT_NFS4ACLS;
694 			MNT_IUNLOCK(mp);
695 		}
696 
697 	}
698 
699 	MNT_ILOCK(mp);
700 	/*
701 	 * This is racy versus lookup, see ufs_fplookup_vexec for details.
702 	 */
703 	if ((mp->mnt_kern_flag & MNTK_FPLOOKUP) != 0)
704 		panic("MNTK_FPLOOKUP set on mount %p when it should not be", mp);
705 	if ((mp->mnt_flag & (MNT_ACLS | MNT_NFS4ACLS | MNT_UNION)) == 0)
706 		mp->mnt_kern_flag |= MNTK_FPLOOKUP;
707 	MNT_IUNLOCK(mp);
708 
709 	vfs_mountedfrom(mp, fspec);
710 	return (0);
711 }
712 
713 /*
714  * Compatibility with old mount system call.
715  */
716 
717 static int
718 ffs_cmount(struct mntarg *ma, void *data, uint64_t flags)
719 {
720 	struct ufs_args args;
721 	int error;
722 
723 	if (data == NULL)
724 		return (EINVAL);
725 	error = copyin(data, &args, sizeof args);
726 	if (error)
727 		return (error);
728 
729 	ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
730 	ma = mount_arg(ma, "export", &args.export, sizeof(args.export));
731 	error = kernel_mount(ma, flags);
732 
733 	return (error);
734 }
735 
736 /*
737  * Reload all incore data for a filesystem (used after running fsck on
738  * the root filesystem and finding things to fix). If the 'force' flag
739  * is 0, the filesystem must be mounted read-only.
740  *
741  * Things to do to update the mount:
742  *	1) invalidate all cached meta-data.
743  *	2) re-read superblock from disk.
744  *	3) re-read summary information from disk.
745  *	4) invalidate all inactive vnodes.
746  *	5) clear MNTK_SUSPEND2 and MNTK_SUSPENDED flags, allowing secondary
747  *	   writers, if requested.
748  *	6) invalidate all cached file data.
749  *	7) re-read inode data for all active vnodes.
750  */
751 int
752 ffs_reload(struct mount *mp, int flags)
753 {
754 	struct vnode *vp, *mvp, *devvp;
755 	struct inode *ip;
756 	void *space;
757 	struct buf *bp;
758 	struct fs *fs, *newfs;
759 	struct ufsmount *ump;
760 	ufs2_daddr_t sblockloc;
761 	int i, blks, error;
762 	u_long size;
763 	int32_t *lp;
764 
765 	ump = VFSTOUFS(mp);
766 
767 	MNT_ILOCK(mp);
768 	if ((mp->mnt_flag & MNT_RDONLY) == 0 && (flags & FFSR_FORCE) == 0) {
769 		MNT_IUNLOCK(mp);
770 		return (EINVAL);
771 	}
772 	MNT_IUNLOCK(mp);
773 
774 	/*
775 	 * Step 1: invalidate all cached meta-data.
776 	 */
777 	devvp = VFSTOUFS(mp)->um_devvp;
778 	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
779 	if (vinvalbuf(devvp, 0, 0, 0) != 0)
780 		panic("ffs_reload: dirty1");
781 	VOP_UNLOCK(devvp);
782 
783 	/*
784 	 * Step 2: re-read superblock from disk.
785 	 */
786 	fs = VFSTOUFS(mp)->um_fs;
787 	if ((error = bread(devvp, btodb(fs->fs_sblockloc), fs->fs_sbsize,
788 	    NOCRED, &bp)) != 0)
789 		return (error);
790 	newfs = (struct fs *)bp->b_data;
791 	if ((newfs->fs_magic != FS_UFS1_MAGIC &&
792 	     newfs->fs_magic != FS_UFS2_MAGIC) ||
793 	    newfs->fs_bsize > MAXBSIZE ||
794 	    newfs->fs_bsize < sizeof(struct fs)) {
795 			brelse(bp);
796 			return (EIO);		/* XXX needs translation */
797 	}
798 	/*
799 	 * Preserve the summary information, read-only status, and
800 	 * superblock location by copying these fields into our new
801 	 * superblock before using it to update the existing superblock.
802 	 */
803 	newfs->fs_si = fs->fs_si;
804 	newfs->fs_ronly = fs->fs_ronly;
805 	sblockloc = fs->fs_sblockloc;
806 	bcopy(newfs, fs, (u_int)fs->fs_sbsize);
807 	brelse(bp);
808 	ump->um_bsize = fs->fs_bsize;
809 	ump->um_maxsymlinklen = fs->fs_maxsymlinklen;
810 	ffs_oldfscompat_read(fs, VFSTOUFS(mp), sblockloc);
811 	UFS_LOCK(ump);
812 	if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
813 		printf("WARNING: %s: reload pending error: blocks %jd "
814 		    "files %d\n", mp->mnt_stat.f_mntonname,
815 		    (intmax_t)fs->fs_pendingblocks, fs->fs_pendinginodes);
816 		fs->fs_pendingblocks = 0;
817 		fs->fs_pendinginodes = 0;
818 	}
819 	UFS_UNLOCK(ump);
820 
821 	/*
822 	 * Step 3: re-read summary information from disk.
823 	 */
824 	size = fs->fs_cssize;
825 	blks = howmany(size, fs->fs_fsize);
826 	if (fs->fs_contigsumsize > 0)
827 		size += fs->fs_ncg * sizeof(int32_t);
828 	size += fs->fs_ncg * sizeof(u_int8_t);
829 	free(fs->fs_csp, M_UFSMNT);
830 	space = malloc(size, M_UFSMNT, M_WAITOK);
831 	fs->fs_csp = space;
832 	for (i = 0; i < blks; i += fs->fs_frag) {
833 		size = fs->fs_bsize;
834 		if (i + fs->fs_frag > blks)
835 			size = (blks - i) * fs->fs_fsize;
836 		error = bread(devvp, fsbtodb(fs, fs->fs_csaddr + i), size,
837 		    NOCRED, &bp);
838 		if (error)
839 			return (error);
840 		bcopy(bp->b_data, space, (u_int)size);
841 		space = (char *)space + size;
842 		brelse(bp);
843 	}
844 	/*
845 	 * We no longer know anything about clusters per cylinder group.
846 	 */
847 	if (fs->fs_contigsumsize > 0) {
848 		fs->fs_maxcluster = lp = space;
849 		for (i = 0; i < fs->fs_ncg; i++)
850 			*lp++ = fs->fs_contigsumsize;
851 		space = lp;
852 	}
853 	size = fs->fs_ncg * sizeof(u_int8_t);
854 	fs->fs_contigdirs = (u_int8_t *)space;
855 	bzero(fs->fs_contigdirs, size);
856 	if ((flags & FFSR_UNSUSPEND) != 0) {
857 		MNT_ILOCK(mp);
858 		mp->mnt_kern_flag &= ~(MNTK_SUSPENDED | MNTK_SUSPEND2);
859 		wakeup(&mp->mnt_flag);
860 		MNT_IUNLOCK(mp);
861 	}
862 
863 loop:
864 	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
865 		/*
866 		 * Skip syncer vnode.
867 		 */
868 		if (vp->v_type == VNON) {
869 			VI_UNLOCK(vp);
870 			continue;
871 		}
872 		/*
873 		 * Step 4: invalidate all cached file data.
874 		 */
875 		if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) {
876 			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
877 			goto loop;
878 		}
879 		if (vinvalbuf(vp, 0, 0, 0))
880 			panic("ffs_reload: dirty2");
881 		/*
882 		 * Step 5: re-read inode data for all active vnodes.
883 		 */
884 		ip = VTOI(vp);
885 		error =
886 		    bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
887 		    (int)fs->fs_bsize, NOCRED, &bp);
888 		if (error) {
889 			vput(vp);
890 			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
891 			return (error);
892 		}
893 		if ((error = ffs_load_inode(bp, ip, fs, ip->i_number)) != 0) {
894 			brelse(bp);
895 			vput(vp);
896 			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
897 			return (error);
898 		}
899 		ip->i_effnlink = ip->i_nlink;
900 		brelse(bp);
901 		vput(vp);
902 	}
903 	return (0);
904 }
905 
906 /*
907  * Common code for mount and mountroot
908  */
909 static int
910 ffs_mountfs(struct vnode *odevvp, struct mount *mp, struct thread *td)
911 {
912 	struct ufsmount *ump;
913 	struct fs *fs;
914 	struct cdev *dev;
915 	int error, i, len, ronly;
916 	struct ucred *cred;
917 	struct g_consumer *cp;
918 	struct mount *nmp;
919 	struct vnode *devvp;
920 	int candelete, canspeedup;
921 
922 	fs = NULL;
923 	ump = NULL;
924 	cred = td ? td->td_ucred : NOCRED;
925 	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
926 
927 	devvp = mntfs_allocvp(mp, odevvp);
928 	KASSERT(devvp->v_type == VCHR, ("reclaimed devvp"));
929 	dev = devvp->v_rdev;
930 	KASSERT(dev->si_snapdata == NULL, ("non-NULL snapshot data"));
931 	if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0,
932 	    (uintptr_t)mp) == 0) {
933 		mntfs_freevp(devvp);
934 		return (EBUSY);
935 	}
936 	g_topology_lock();
937 	error = g_vfs_open(devvp, &cp, "ffs", ronly ? 0 : 1);
938 	g_topology_unlock();
939 	if (error != 0) {
940 		atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0);
941 		mntfs_freevp(devvp);
942 		return (error);
943 	}
944 	dev_ref(dev);
945 	devvp->v_bufobj.bo_ops = &ffs_ops;
946 	BO_LOCK(&odevvp->v_bufobj);
947 	odevvp->v_bufobj.bo_flag |= BO_NOBUFS;
948 	BO_UNLOCK(&odevvp->v_bufobj);
949 	VOP_UNLOCK(devvp);
950 	if (dev->si_iosize_max != 0)
951 		mp->mnt_iosize_max = dev->si_iosize_max;
952 	if (mp->mnt_iosize_max > maxphys)
953 		mp->mnt_iosize_max = maxphys;
954 	if ((SBLOCKSIZE % cp->provider->sectorsize) != 0) {
955 		error = EINVAL;
956 		vfs_mount_error(mp,
957 		    "Invalid sectorsize %d for superblock size %d",
958 		    cp->provider->sectorsize, SBLOCKSIZE);
959 		goto out;
960 	}
961 	/* fetch the superblock and summary information */
962 	if ((mp->mnt_flag & (MNT_ROOTFS | MNT_FORCE)) != 0)
963 		error = ffs_sbsearch(devvp, &fs, 0, M_UFSMNT, ffs_use_bread);
964 	else
965 		error = ffs_sbget(devvp, &fs, UFS_STDSB, 0, M_UFSMNT,
966 		    ffs_use_bread);
967 	if (error != 0)
968 		goto out;
969 	fs->fs_flags &= ~FS_UNCLEAN;
970 	if (fs->fs_clean == 0) {
971 		fs->fs_flags |= FS_UNCLEAN;
972 		if (ronly || (mp->mnt_flag & MNT_FORCE) ||
973 		    ((fs->fs_flags & (FS_SUJ | FS_NEEDSFSCK)) == 0 &&
974 		     (fs->fs_flags & FS_DOSOFTDEP))) {
975 			printf("WARNING: %s was not properly dismounted\n",
976 			    mp->mnt_stat.f_mntonname);
977 		} else {
978 			vfs_mount_error(mp, "R/W mount on %s denied. "
979 			    "Filesystem is not clean - run fsck.%s",
980 			    mp->mnt_stat.f_mntonname,
981 			    (fs->fs_flags & FS_SUJ) == 0 ? "" :
982 			    " Forced mount will invalidate journal contents");
983 			error = EPERM;
984 			goto out;
985 		}
986 		if ((fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) &&
987 		    (mp->mnt_flag & MNT_FORCE)) {
988 			printf("WARNING: %s: lost blocks %jd files %d\n",
989 			    mp->mnt_stat.f_mntonname,
990 			    (intmax_t)fs->fs_pendingblocks,
991 			    fs->fs_pendinginodes);
992 			fs->fs_pendingblocks = 0;
993 			fs->fs_pendinginodes = 0;
994 		}
995 	}
996 	if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
997 		printf("WARNING: %s: mount pending error: blocks %jd "
998 		    "files %d\n", mp->mnt_stat.f_mntonname,
999 		    (intmax_t)fs->fs_pendingblocks, fs->fs_pendinginodes);
1000 		fs->fs_pendingblocks = 0;
1001 		fs->fs_pendinginodes = 0;
1002 	}
1003 	if ((fs->fs_flags & FS_GJOURNAL) != 0) {
1004 #ifdef UFS_GJOURNAL
1005 		/*
1006 		 * Get journal provider name.
1007 		 */
1008 		len = 1024;
1009 		mp->mnt_gjprovider = malloc((u_long)len, M_UFSMNT, M_WAITOK);
1010 		if (g_io_getattr("GJOURNAL::provider", cp, &len,
1011 		    mp->mnt_gjprovider) == 0) {
1012 			mp->mnt_gjprovider = realloc(mp->mnt_gjprovider, len,
1013 			    M_UFSMNT, M_WAITOK);
1014 			MNT_ILOCK(mp);
1015 			mp->mnt_flag |= MNT_GJOURNAL;
1016 			MNT_IUNLOCK(mp);
1017 		} else {
1018 			if ((mp->mnt_flag & MNT_RDONLY) == 0)
1019 				printf("WARNING: %s: GJOURNAL flag on fs "
1020 				    "but no gjournal provider below\n",
1021 				    mp->mnt_stat.f_mntonname);
1022 			free(mp->mnt_gjprovider, M_UFSMNT);
1023 			mp->mnt_gjprovider = NULL;
1024 		}
1025 #else
1026 		printf("WARNING: %s: GJOURNAL flag on fs but no "
1027 		    "UFS_GJOURNAL support\n", mp->mnt_stat.f_mntonname);
1028 #endif
1029 	} else {
1030 		mp->mnt_gjprovider = NULL;
1031 	}
1032 	ump = malloc(sizeof *ump, M_UFSMNT, M_WAITOK | M_ZERO);
1033 	ump->um_cp = cp;
1034 	ump->um_bo = &devvp->v_bufobj;
1035 	ump->um_fs = fs;
1036 	if (fs->fs_magic == FS_UFS1_MAGIC) {
1037 		ump->um_fstype = UFS1;
1038 		ump->um_balloc = ffs_balloc_ufs1;
1039 	} else {
1040 		ump->um_fstype = UFS2;
1041 		ump->um_balloc = ffs_balloc_ufs2;
1042 	}
1043 	ump->um_blkatoff = ffs_blkatoff;
1044 	ump->um_truncate = ffs_truncate;
1045 	ump->um_update = ffs_update;
1046 	ump->um_valloc = ffs_valloc;
1047 	ump->um_vfree = ffs_vfree;
1048 	ump->um_ifree = ffs_ifree;
1049 	ump->um_rdonly = ffs_rdonly;
1050 	ump->um_snapgone = ffs_snapgone;
1051 	if ((mp->mnt_flag & MNT_UNTRUSTED) != 0)
1052 		ump->um_check_blkno = ffs_check_blkno;
1053 	else
1054 		ump->um_check_blkno = NULL;
1055 	mtx_init(UFS_MTX(ump), "FFS", "FFS Lock", MTX_DEF);
1056 	sx_init(&ump->um_checkpath_lock, "uchpth");
1057 	ffs_oldfscompat_read(fs, ump, fs->fs_sblockloc);
1058 	fs->fs_ronly = ronly;
1059 	fs->fs_active = NULL;
1060 	mp->mnt_data = ump;
1061 	mp->mnt_stat.f_fsid.val[0] = fs->fs_id[0];
1062 	mp->mnt_stat.f_fsid.val[1] = fs->fs_id[1];
1063 	nmp = NULL;
1064 	if (fs->fs_id[0] == 0 || fs->fs_id[1] == 0 ||
1065 	    (nmp = vfs_getvfs(&mp->mnt_stat.f_fsid))) {
1066 		if (nmp)
1067 			vfs_rel(nmp);
1068 		vfs_getnewfsid(mp);
1069 	}
1070 	ump->um_bsize = fs->fs_bsize;
1071 	ump->um_maxsymlinklen = fs->fs_maxsymlinklen;
1072 	MNT_ILOCK(mp);
1073 	mp->mnt_flag |= MNT_LOCAL;
1074 	MNT_IUNLOCK(mp);
1075 	if ((fs->fs_flags & FS_MULTILABEL) != 0) {
1076 #ifdef MAC
1077 		MNT_ILOCK(mp);
1078 		mp->mnt_flag |= MNT_MULTILABEL;
1079 		MNT_IUNLOCK(mp);
1080 #else
1081 		printf("WARNING: %s: multilabel flag on fs but "
1082 		    "no MAC support\n", mp->mnt_stat.f_mntonname);
1083 #endif
1084 	}
1085 	if ((fs->fs_flags & FS_ACLS) != 0) {
1086 #ifdef UFS_ACL
1087 		MNT_ILOCK(mp);
1088 
1089 		if (mp->mnt_flag & MNT_NFS4ACLS)
1090 			printf("WARNING: %s: ACLs flag on fs conflicts with "
1091 			    "\"nfsv4acls\" mount option; option ignored\n",
1092 			    mp->mnt_stat.f_mntonname);
1093 		mp->mnt_flag &= ~MNT_NFS4ACLS;
1094 		mp->mnt_flag |= MNT_ACLS;
1095 
1096 		MNT_IUNLOCK(mp);
1097 #else
1098 		printf("WARNING: %s: ACLs flag on fs but no ACLs support\n",
1099 		    mp->mnt_stat.f_mntonname);
1100 #endif
1101 	}
1102 	if ((fs->fs_flags & FS_NFS4ACLS) != 0) {
1103 #ifdef UFS_ACL
1104 		MNT_ILOCK(mp);
1105 
1106 		if (mp->mnt_flag & MNT_ACLS)
1107 			printf("WARNING: %s: NFSv4 ACLs flag on fs conflicts "
1108 			    "with \"acls\" mount option; option ignored\n",
1109 			    mp->mnt_stat.f_mntonname);
1110 		mp->mnt_flag &= ~MNT_ACLS;
1111 		mp->mnt_flag |= MNT_NFS4ACLS;
1112 
1113 		MNT_IUNLOCK(mp);
1114 #else
1115 		printf("WARNING: %s: NFSv4 ACLs flag on fs but no "
1116 		    "ACLs support\n", mp->mnt_stat.f_mntonname);
1117 #endif
1118 	}
1119 	if ((fs->fs_flags & FS_TRIM) != 0) {
1120 		len = sizeof(int);
1121 		if (g_io_getattr("GEOM::candelete", cp, &len,
1122 		    &candelete) == 0) {
1123 			if (candelete)
1124 				ump->um_flags |= UM_CANDELETE;
1125 			else
1126 				printf("WARNING: %s: TRIM flag on fs but disk "
1127 				    "does not support TRIM\n",
1128 				    mp->mnt_stat.f_mntonname);
1129 		} else {
1130 			printf("WARNING: %s: TRIM flag on fs but disk does "
1131 			    "not confirm that it supports TRIM\n",
1132 			    mp->mnt_stat.f_mntonname);
1133 		}
1134 		if (((ump->um_flags) & UM_CANDELETE) != 0) {
1135 			ump->um_trim_tq = taskqueue_create("trim", M_WAITOK,
1136 			    taskqueue_thread_enqueue, &ump->um_trim_tq);
1137 			taskqueue_start_threads(&ump->um_trim_tq, 1, PVFS,
1138 			    "%s trim", mp->mnt_stat.f_mntonname);
1139 			ump->um_trimhash = hashinit(MAXTRIMIO, M_TRIM,
1140 			    &ump->um_trimlisthashsize);
1141 		}
1142 	}
1143 
1144 	len = sizeof(int);
1145 	if (g_io_getattr("GEOM::canspeedup", cp, &len, &canspeedup) == 0) {
1146 		if (canspeedup)
1147 			ump->um_flags |= UM_CANSPEEDUP;
1148 	}
1149 
1150 	ump->um_mountp = mp;
1151 	ump->um_dev = dev;
1152 	ump->um_devvp = devvp;
1153 	ump->um_odevvp = odevvp;
1154 	ump->um_nindir = fs->fs_nindir;
1155 	ump->um_bptrtodb = fs->fs_fsbtodb;
1156 	ump->um_seqinc = fs->fs_frag;
1157 	for (i = 0; i < MAXQUOTAS; i++)
1158 		ump->um_quotas[i] = NULLVP;
1159 #ifdef UFS_EXTATTR
1160 	ufs_extattr_uepm_init(&ump->um_extattr);
1161 #endif
1162 	/*
1163 	 * Set FS local "last mounted on" information (NULL pad)
1164 	 */
1165 	bzero(fs->fs_fsmnt, MAXMNTLEN);
1166 	strlcpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, MAXMNTLEN);
1167 	mp->mnt_stat.f_iosize = fs->fs_bsize;
1168 
1169 	if (mp->mnt_flag & MNT_ROOTFS) {
1170 		/*
1171 		 * Root mount; update timestamp in mount structure.
1172 		 * this will be used by the common root mount code
1173 		 * to update the system clock.
1174 		 */
1175 		mp->mnt_time = fs->fs_time;
1176 	}
1177 
1178 	if (ronly == 0) {
1179 		fs->fs_mtime = time_second;
1180 		if ((fs->fs_flags & FS_DOSOFTDEP) &&
1181 		    (error = softdep_mount(devvp, mp, fs, cred)) != 0) {
1182 			ffs_flushfiles(mp, FORCECLOSE, td);
1183 			goto out;
1184 		}
1185 		if (fs->fs_snapinum[0] != 0)
1186 			ffs_snapshot_mount(mp);
1187 		fs->fs_fmod = 1;
1188 		fs->fs_clean = 0;
1189 		(void) ffs_sbupdate(ump, MNT_WAIT, 0);
1190 	}
1191 	/*
1192 	 * Initialize filesystem state information in mount struct.
1193 	 */
1194 	MNT_ILOCK(mp);
1195 	mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED |
1196 	    MNTK_NO_IOPF | MNTK_UNMAPPED_BUFS | MNTK_USES_BCACHE;
1197 	MNT_IUNLOCK(mp);
1198 #ifdef UFS_EXTATTR
1199 #ifdef UFS_EXTATTR_AUTOSTART
1200 	/*
1201 	 *
1202 	 * Auto-starting does the following:
1203 	 *	- check for /.attribute in the fs, and extattr_start if so
1204 	 *	- for each file in .attribute, enable that file with
1205 	 * 	  an attribute of the same name.
1206 	 * Not clear how to report errors -- probably eat them.
1207 	 * This would all happen while the filesystem was busy/not
1208 	 * available, so would effectively be "atomic".
1209 	 */
1210 	(void) ufs_extattr_autostart(mp, td);
1211 #endif /* !UFS_EXTATTR_AUTOSTART */
1212 #endif /* !UFS_EXTATTR */
1213 	return (0);
1214 out:
1215 	if (fs != NULL) {
1216 		free(fs->fs_csp, M_UFSMNT);
1217 		free(fs->fs_si, M_UFSMNT);
1218 		free(fs, M_UFSMNT);
1219 	}
1220 	if (cp != NULL) {
1221 		g_topology_lock();
1222 		g_vfs_close(cp);
1223 		g_topology_unlock();
1224 	}
1225 	if (ump != NULL) {
1226 		mtx_destroy(UFS_MTX(ump));
1227 		sx_destroy(&ump->um_checkpath_lock);
1228 		if (mp->mnt_gjprovider != NULL) {
1229 			free(mp->mnt_gjprovider, M_UFSMNT);
1230 			mp->mnt_gjprovider = NULL;
1231 		}
1232 		MPASS(ump->um_softdep == NULL);
1233 		free(ump, M_UFSMNT);
1234 		mp->mnt_data = NULL;
1235 	}
1236 	BO_LOCK(&odevvp->v_bufobj);
1237 	odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS;
1238 	BO_UNLOCK(&odevvp->v_bufobj);
1239 	atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0);
1240 	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1241 	mntfs_freevp(devvp);
1242 	dev_rel(dev);
1243 	return (error);
1244 }
1245 
1246 /*
1247  * A read function for use by filesystem-layer routines.
1248  */
1249 static int
1250 ffs_use_bread(void *devfd, off_t loc, void **bufp, int size)
1251 {
1252 	struct buf *bp;
1253 	int error;
1254 
1255 	KASSERT(*bufp == NULL, ("ffs_use_bread: non-NULL *bufp %p\n", *bufp));
1256 	*bufp = malloc(size, M_UFSMNT, M_WAITOK);
1257 	if ((error = bread((struct vnode *)devfd, btodb(loc), size, NOCRED,
1258 	    &bp)) != 0)
1259 		return (error);
1260 	bcopy(bp->b_data, *bufp, size);
1261 	bp->b_flags |= B_INVAL | B_NOCACHE;
1262 	brelse(bp);
1263 	return (0);
1264 }
1265 
1266 static int bigcgs = 0;
1267 SYSCTL_INT(_debug, OID_AUTO, bigcgs, CTLFLAG_RW, &bigcgs, 0, "");
1268 
1269 /*
1270  * Sanity checks for loading old filesystem superblocks.
1271  * See ffs_oldfscompat_write below for unwound actions.
1272  *
1273  * XXX - Parts get retired eventually.
1274  * Unfortunately new bits get added.
1275  */
1276 static void
1277 ffs_oldfscompat_read(struct fs *fs,
1278 	struct ufsmount *ump,
1279 	ufs2_daddr_t sblockloc)
1280 {
1281 	off_t maxfilesize;
1282 
1283 	/*
1284 	 * If not yet done, update fs_flags location and value of fs_sblockloc.
1285 	 */
1286 	if ((fs->fs_old_flags & FS_FLAGS_UPDATED) == 0) {
1287 		fs->fs_flags = fs->fs_old_flags;
1288 		fs->fs_old_flags |= FS_FLAGS_UPDATED;
1289 		fs->fs_sblockloc = sblockloc;
1290 	}
1291 	/*
1292 	 * If not yet done, update UFS1 superblock with new wider fields.
1293 	 */
1294 	if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_maxbsize != fs->fs_bsize) {
1295 		fs->fs_maxbsize = fs->fs_bsize;
1296 		fs->fs_time = fs->fs_old_time;
1297 		fs->fs_size = fs->fs_old_size;
1298 		fs->fs_dsize = fs->fs_old_dsize;
1299 		fs->fs_csaddr = fs->fs_old_csaddr;
1300 		fs->fs_cstotal.cs_ndir = fs->fs_old_cstotal.cs_ndir;
1301 		fs->fs_cstotal.cs_nbfree = fs->fs_old_cstotal.cs_nbfree;
1302 		fs->fs_cstotal.cs_nifree = fs->fs_old_cstotal.cs_nifree;
1303 		fs->fs_cstotal.cs_nffree = fs->fs_old_cstotal.cs_nffree;
1304 	}
1305 	if (fs->fs_magic == FS_UFS1_MAGIC &&
1306 	    fs->fs_old_inodefmt < FS_44INODEFMT) {
1307 		fs->fs_maxfilesize = ((uint64_t)1 << 31) - 1;
1308 		fs->fs_qbmask = ~fs->fs_bmask;
1309 		fs->fs_qfmask = ~fs->fs_fmask;
1310 	}
1311 	if (fs->fs_magic == FS_UFS1_MAGIC) {
1312 		ump->um_savedmaxfilesize = fs->fs_maxfilesize;
1313 		maxfilesize = (uint64_t)0x80000000 * fs->fs_bsize - 1;
1314 		if (fs->fs_maxfilesize > maxfilesize)
1315 			fs->fs_maxfilesize = maxfilesize;
1316 	}
1317 	/* Compatibility for old filesystems */
1318 	if (fs->fs_avgfilesize <= 0)
1319 		fs->fs_avgfilesize = AVFILESIZ;
1320 	if (fs->fs_avgfpdir <= 0)
1321 		fs->fs_avgfpdir = AFPDIR;
1322 	if (bigcgs) {
1323 		fs->fs_save_cgsize = fs->fs_cgsize;
1324 		fs->fs_cgsize = fs->fs_bsize;
1325 	}
1326 }
1327 
1328 /*
1329  * Unwinding superblock updates for old filesystems.
1330  * See ffs_oldfscompat_read above for details.
1331  *
1332  * XXX - Parts get retired eventually.
1333  * Unfortunately new bits get added.
1334  */
1335 void
1336 ffs_oldfscompat_write(struct fs *fs, struct ufsmount *ump)
1337 {
1338 
1339 	/*
1340 	 * Copy back UFS2 updated fields that UFS1 inspects.
1341 	 */
1342 	if (fs->fs_magic == FS_UFS1_MAGIC) {
1343 		fs->fs_old_time = fs->fs_time;
1344 		fs->fs_old_cstotal.cs_ndir = fs->fs_cstotal.cs_ndir;
1345 		fs->fs_old_cstotal.cs_nbfree = fs->fs_cstotal.cs_nbfree;
1346 		fs->fs_old_cstotal.cs_nifree = fs->fs_cstotal.cs_nifree;
1347 		fs->fs_old_cstotal.cs_nffree = fs->fs_cstotal.cs_nffree;
1348 		fs->fs_maxfilesize = ump->um_savedmaxfilesize;
1349 	}
1350 	if (bigcgs) {
1351 		fs->fs_cgsize = fs->fs_save_cgsize;
1352 		fs->fs_save_cgsize = 0;
1353 	}
1354 }
1355 
1356 /*
1357  * unmount system call
1358  */
1359 static int
1360 ffs_unmount(struct mount *mp, int mntflags)
1361 {
1362 	struct thread *td;
1363 	struct ufsmount *ump = VFSTOUFS(mp);
1364 	struct fs *fs;
1365 	int error, flags, susp;
1366 #ifdef UFS_EXTATTR
1367 	int e_restart;
1368 #endif
1369 
1370 	flags = 0;
1371 	td = curthread;
1372 	fs = ump->um_fs;
1373 	if (mntflags & MNT_FORCE)
1374 		flags |= FORCECLOSE;
1375 	susp = fs->fs_ronly == 0;
1376 #ifdef UFS_EXTATTR
1377 	if ((error = ufs_extattr_stop(mp, td))) {
1378 		if (error != EOPNOTSUPP)
1379 			printf("WARNING: unmount %s: ufs_extattr_stop "
1380 			    "returned errno %d\n", mp->mnt_stat.f_mntonname,
1381 			    error);
1382 		e_restart = 0;
1383 	} else {
1384 		ufs_extattr_uepm_destroy(&ump->um_extattr);
1385 		e_restart = 1;
1386 	}
1387 #endif
1388 	if (susp) {
1389 		error = vfs_write_suspend_umnt(mp);
1390 		if (error != 0)
1391 			goto fail1;
1392 	}
1393 	if (MOUNTEDSOFTDEP(mp))
1394 		error = softdep_flushfiles(mp, flags, td);
1395 	else
1396 		error = ffs_flushfiles(mp, flags, td);
1397 	if (error != 0 && !ffs_fsfail_cleanup(ump, error))
1398 		goto fail;
1399 
1400 	UFS_LOCK(ump);
1401 	if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
1402 		printf("WARNING: unmount %s: pending error: blocks %jd "
1403 		    "files %d\n", fs->fs_fsmnt, (intmax_t)fs->fs_pendingblocks,
1404 		    fs->fs_pendinginodes);
1405 		fs->fs_pendingblocks = 0;
1406 		fs->fs_pendinginodes = 0;
1407 	}
1408 	UFS_UNLOCK(ump);
1409 	if (MOUNTEDSOFTDEP(mp))
1410 		softdep_unmount(mp);
1411 	MPASS(ump->um_softdep == NULL);
1412 	if (fs->fs_ronly == 0) {
1413 		fs->fs_clean = fs->fs_flags & (FS_UNCLEAN|FS_NEEDSFSCK) ? 0 : 1;
1414 		error = ffs_sbupdate(ump, MNT_WAIT, 0);
1415 		if (ffs_fsfail_cleanup(ump, error))
1416 			error = 0;
1417 		if (error != 0 && !ffs_fsfail_cleanup(ump, error)) {
1418 			fs->fs_clean = 0;
1419 			goto fail;
1420 		}
1421 	}
1422 	if (susp)
1423 		vfs_write_resume(mp, VR_START_WRITE);
1424 	if (ump->um_trim_tq != NULL) {
1425 		MPASS(ump->um_trim_inflight == 0);
1426 		taskqueue_free(ump->um_trim_tq);
1427 		free (ump->um_trimhash, M_TRIM);
1428 	}
1429 	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
1430 	g_topology_lock();
1431 	g_vfs_close(ump->um_cp);
1432 	g_topology_unlock();
1433 	BO_LOCK(&ump->um_odevvp->v_bufobj);
1434 	ump->um_odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS;
1435 	BO_UNLOCK(&ump->um_odevvp->v_bufobj);
1436 	atomic_store_rel_ptr((uintptr_t *)&ump->um_dev->si_mountpt, 0);
1437 	mntfs_freevp(ump->um_devvp);
1438 	vrele(ump->um_odevvp);
1439 	dev_rel(ump->um_dev);
1440 	mtx_destroy(UFS_MTX(ump));
1441 	sx_destroy(&ump->um_checkpath_lock);
1442 	if (mp->mnt_gjprovider != NULL) {
1443 		free(mp->mnt_gjprovider, M_UFSMNT);
1444 		mp->mnt_gjprovider = NULL;
1445 	}
1446 	free(fs->fs_csp, M_UFSMNT);
1447 	free(fs->fs_si, M_UFSMNT);
1448 	free(fs, M_UFSMNT);
1449 	free(ump, M_UFSMNT);
1450 	mp->mnt_data = NULL;
1451 	MNT_ILOCK(mp);
1452 	mp->mnt_flag &= ~MNT_LOCAL;
1453 	MNT_IUNLOCK(mp);
1454 	if (td->td_su == mp) {
1455 		td->td_su = NULL;
1456 		vfs_rel(mp);
1457 	}
1458 	return (error);
1459 
1460 fail:
1461 	if (susp)
1462 		vfs_write_resume(mp, VR_START_WRITE);
1463 fail1:
1464 #ifdef UFS_EXTATTR
1465 	if (e_restart) {
1466 		ufs_extattr_uepm_init(&ump->um_extattr);
1467 #ifdef UFS_EXTATTR_AUTOSTART
1468 		(void) ufs_extattr_autostart(mp, td);
1469 #endif
1470 	}
1471 #endif
1472 
1473 	return (error);
1474 }
1475 
1476 /*
1477  * Flush out all the files in a filesystem.
1478  */
1479 int
1480 ffs_flushfiles(struct mount *mp, int flags, struct thread *td)
1481 {
1482 	struct ufsmount *ump;
1483 	int qerror, error;
1484 
1485 	ump = VFSTOUFS(mp);
1486 	qerror = 0;
1487 #ifdef QUOTA
1488 	if (mp->mnt_flag & MNT_QUOTA) {
1489 		int i;
1490 		error = vflush(mp, 0, SKIPSYSTEM|flags, td);
1491 		if (error)
1492 			return (error);
1493 		for (i = 0; i < MAXQUOTAS; i++) {
1494 			error = quotaoff(td, mp, i);
1495 			if (error != 0) {
1496 				if ((flags & EARLYFLUSH) == 0)
1497 					return (error);
1498 				else
1499 					qerror = error;
1500 			}
1501 		}
1502 
1503 		/*
1504 		 * Here we fall through to vflush again to ensure that
1505 		 * we have gotten rid of all the system vnodes, unless
1506 		 * quotas must not be closed.
1507 		 */
1508 	}
1509 #endif
1510 	/* devvp is not locked there */
1511 	if (ump->um_devvp->v_vflag & VV_COPYONWRITE) {
1512 		if ((error = vflush(mp, 0, SKIPSYSTEM | flags, td)) != 0)
1513 			return (error);
1514 		ffs_snapshot_unmount(mp);
1515 		flags |= FORCECLOSE;
1516 		/*
1517 		 * Here we fall through to vflush again to ensure
1518 		 * that we have gotten rid of all the system vnodes.
1519 		 */
1520 	}
1521 
1522 	/*
1523 	 * Do not close system files if quotas were not closed, to be
1524 	 * able to sync the remaining dquots.  The freeblks softupdate
1525 	 * workitems might hold a reference on a dquot, preventing
1526 	 * quotaoff() from completing.  Next round of
1527 	 * softdep_flushworklist() iteration should process the
1528 	 * blockers, allowing the next run of quotaoff() to finally
1529 	 * flush held dquots.
1530 	 *
1531 	 * Otherwise, flush all the files.
1532 	 */
1533 	if (qerror == 0 && (error = vflush(mp, 0, flags, td)) != 0)
1534 		return (error);
1535 
1536 	/*
1537 	 * If this is a forcible unmount and there were any files that
1538 	 * were unlinked but still open, then vflush() will have
1539 	 * truncated and freed those files, which might have started
1540 	 * some trim work.  Wait here for any trims to complete
1541 	 * and process the blkfrees which follow the trims.
1542 	 * This may create more dirty devvp buffers and softdep deps.
1543 	 */
1544 	if (ump->um_trim_tq != NULL) {
1545 		while (ump->um_trim_inflight != 0)
1546 			pause("ufsutr", hz);
1547 		taskqueue_drain_all(ump->um_trim_tq);
1548 	}
1549 
1550 	/*
1551 	 * Flush filesystem metadata.
1552 	 */
1553 	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
1554 	error = VOP_FSYNC(ump->um_devvp, MNT_WAIT, td);
1555 	VOP_UNLOCK(ump->um_devvp);
1556 	return (error);
1557 }
1558 
1559 /*
1560  * Get filesystem statistics.
1561  */
1562 static int
1563 ffs_statfs(struct mount *mp, struct statfs *sbp)
1564 {
1565 	struct ufsmount *ump;
1566 	struct fs *fs;
1567 
1568 	ump = VFSTOUFS(mp);
1569 	fs = ump->um_fs;
1570 	if (fs->fs_magic != FS_UFS1_MAGIC && fs->fs_magic != FS_UFS2_MAGIC)
1571 		panic("ffs_statfs");
1572 	sbp->f_version = STATFS_VERSION;
1573 	sbp->f_bsize = fs->fs_fsize;
1574 	sbp->f_iosize = fs->fs_bsize;
1575 	sbp->f_blocks = fs->fs_dsize;
1576 	UFS_LOCK(ump);
1577 	sbp->f_bfree = fs->fs_cstotal.cs_nbfree * fs->fs_frag +
1578 	    fs->fs_cstotal.cs_nffree + dbtofsb(fs, fs->fs_pendingblocks);
1579 	sbp->f_bavail = freespace(fs, fs->fs_minfree) +
1580 	    dbtofsb(fs, fs->fs_pendingblocks);
1581 	sbp->f_files =  fs->fs_ncg * fs->fs_ipg - UFS_ROOTINO;
1582 	sbp->f_ffree = fs->fs_cstotal.cs_nifree + fs->fs_pendinginodes;
1583 	UFS_UNLOCK(ump);
1584 	sbp->f_namemax = UFS_MAXNAMLEN;
1585 	return (0);
1586 }
1587 
1588 static bool
1589 sync_doupdate(struct inode *ip)
1590 {
1591 
1592 	return ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED |
1593 	    IN_UPDATE)) != 0);
1594 }
1595 
1596 static int
1597 ffs_sync_lazy_filter(struct vnode *vp, void *arg __unused)
1598 {
1599 	struct inode *ip;
1600 
1601 	/*
1602 	 * Flags are safe to access because ->v_data invalidation
1603 	 * is held off by listmtx.
1604 	 */
1605 	if (vp->v_type == VNON)
1606 		return (false);
1607 	ip = VTOI(vp);
1608 	if (!sync_doupdate(ip) && (vp->v_iflag & VI_OWEINACT) == 0)
1609 		return (false);
1610 	return (true);
1611 }
1612 
1613 /*
1614  * For a lazy sync, we only care about access times, quotas and the
1615  * superblock.  Other filesystem changes are already converted to
1616  * cylinder group blocks or inode blocks updates and are written to
1617  * disk by syncer.
1618  */
1619 static int
1620 ffs_sync_lazy(struct mount *mp)
1621 {
1622 	struct vnode *mvp, *vp;
1623 	struct inode *ip;
1624 	int allerror, error;
1625 
1626 	allerror = 0;
1627 	if ((mp->mnt_flag & MNT_NOATIME) != 0) {
1628 #ifdef QUOTA
1629 		qsync(mp);
1630 #endif
1631 		goto sbupdate;
1632 	}
1633 	MNT_VNODE_FOREACH_LAZY(vp, mp, mvp, ffs_sync_lazy_filter, NULL) {
1634 		if (vp->v_type == VNON) {
1635 			VI_UNLOCK(vp);
1636 			continue;
1637 		}
1638 		ip = VTOI(vp);
1639 
1640 		/*
1641 		 * The IN_ACCESS flag is converted to IN_MODIFIED by
1642 		 * ufs_close() and ufs_getattr() by the calls to
1643 		 * ufs_itimes_locked(), without subsequent UFS_UPDATE().
1644 		 * Test also all the other timestamp flags too, to pick up
1645 		 * any other cases that could be missed.
1646 		 */
1647 		if (!sync_doupdate(ip) && (vp->v_iflag & VI_OWEINACT) == 0) {
1648 			VI_UNLOCK(vp);
1649 			continue;
1650 		}
1651 		if ((error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK)) != 0)
1652 			continue;
1653 #ifdef QUOTA
1654 		qsyncvp(vp);
1655 #endif
1656 		if (sync_doupdate(ip))
1657 			error = ffs_update(vp, 0);
1658 		if (error != 0)
1659 			allerror = error;
1660 		vput(vp);
1661 	}
1662 sbupdate:
1663 	if (VFSTOUFS(mp)->um_fs->fs_fmod != 0 &&
1664 	    (error = ffs_sbupdate(VFSTOUFS(mp), MNT_LAZY, 0)) != 0)
1665 		allerror = error;
1666 	return (allerror);
1667 }
1668 
1669 /*
1670  * Go through the disk queues to initiate sandbagged IO;
1671  * go through the inodes to write those that have been modified;
1672  * initiate the writing of the super block if it has been modified.
1673  *
1674  * Note: we are always called with the filesystem marked busy using
1675  * vfs_busy().
1676  */
1677 static int
1678 ffs_sync(struct mount *mp, int waitfor)
1679 {
1680 	struct vnode *mvp, *vp, *devvp;
1681 	struct thread *td;
1682 	struct inode *ip;
1683 	struct ufsmount *ump = VFSTOUFS(mp);
1684 	struct fs *fs;
1685 	int error, count, lockreq, allerror = 0;
1686 	int suspend;
1687 	int suspended;
1688 	int secondary_writes;
1689 	int secondary_accwrites;
1690 	int softdep_deps;
1691 	int softdep_accdeps;
1692 	struct bufobj *bo;
1693 
1694 	suspend = 0;
1695 	suspended = 0;
1696 	td = curthread;
1697 	fs = ump->um_fs;
1698 	if (fs->fs_fmod != 0 && fs->fs_ronly != 0)
1699 		panic("%s: ffs_sync: modification on read-only filesystem",
1700 		    fs->fs_fsmnt);
1701 	if (waitfor == MNT_LAZY) {
1702 		if (!rebooting)
1703 			return (ffs_sync_lazy(mp));
1704 		waitfor = MNT_NOWAIT;
1705 	}
1706 
1707 	/*
1708 	 * Write back each (modified) inode.
1709 	 */
1710 	lockreq = LK_EXCLUSIVE | LK_NOWAIT;
1711 	if (waitfor == MNT_SUSPEND) {
1712 		suspend = 1;
1713 		waitfor = MNT_WAIT;
1714 	}
1715 	if (waitfor == MNT_WAIT)
1716 		lockreq = LK_EXCLUSIVE;
1717 	lockreq |= LK_INTERLOCK | LK_SLEEPFAIL;
1718 loop:
1719 	/* Grab snapshot of secondary write counts */
1720 	MNT_ILOCK(mp);
1721 	secondary_writes = mp->mnt_secondary_writes;
1722 	secondary_accwrites = mp->mnt_secondary_accwrites;
1723 	MNT_IUNLOCK(mp);
1724 
1725 	/* Grab snapshot of softdep dependency counts */
1726 	softdep_get_depcounts(mp, &softdep_deps, &softdep_accdeps);
1727 
1728 	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
1729 		/*
1730 		 * Depend on the vnode interlock to keep things stable enough
1731 		 * for a quick test.  Since there might be hundreds of
1732 		 * thousands of vnodes, we cannot afford even a subroutine
1733 		 * call unless there's a good chance that we have work to do.
1734 		 */
1735 		if (vp->v_type == VNON) {
1736 			VI_UNLOCK(vp);
1737 			continue;
1738 		}
1739 		ip = VTOI(vp);
1740 		if ((ip->i_flag &
1741 		    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
1742 		    vp->v_bufobj.bo_dirty.bv_cnt == 0) {
1743 			VI_UNLOCK(vp);
1744 			continue;
1745 		}
1746 		if ((error = vget(vp, lockreq)) != 0) {
1747 			if (error == ENOENT || error == ENOLCK) {
1748 				MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
1749 				goto loop;
1750 			}
1751 			continue;
1752 		}
1753 #ifdef QUOTA
1754 		qsyncvp(vp);
1755 #endif
1756 		for (;;) {
1757 			error = ffs_syncvnode(vp, waitfor, 0);
1758 			if (error == ERELOOKUP)
1759 				continue;
1760 			if (error != 0)
1761 				allerror = error;
1762 			break;
1763 		}
1764 		vput(vp);
1765 	}
1766 	/*
1767 	 * Force stale filesystem control information to be flushed.
1768 	 */
1769 	if (waitfor == MNT_WAIT || rebooting) {
1770 		if ((error = softdep_flushworklist(ump->um_mountp, &count, td)))
1771 			allerror = error;
1772 		if (ffs_fsfail_cleanup(ump, allerror))
1773 			allerror = 0;
1774 		/* Flushed work items may create new vnodes to clean */
1775 		if (allerror == 0 && count)
1776 			goto loop;
1777 	}
1778 
1779 	devvp = ump->um_devvp;
1780 	bo = &devvp->v_bufobj;
1781 	BO_LOCK(bo);
1782 	if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) {
1783 		BO_UNLOCK(bo);
1784 		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
1785 		error = VOP_FSYNC(devvp, waitfor, td);
1786 		VOP_UNLOCK(devvp);
1787 		if (MOUNTEDSOFTDEP(mp) && (error == 0 || error == EAGAIN))
1788 			error = ffs_sbupdate(ump, waitfor, 0);
1789 		if (error != 0)
1790 			allerror = error;
1791 		if (ffs_fsfail_cleanup(ump, allerror))
1792 			allerror = 0;
1793 		if (allerror == 0 && waitfor == MNT_WAIT)
1794 			goto loop;
1795 	} else if (suspend != 0) {
1796 		if (softdep_check_suspend(mp,
1797 					  devvp,
1798 					  softdep_deps,
1799 					  softdep_accdeps,
1800 					  secondary_writes,
1801 					  secondary_accwrites) != 0) {
1802 			MNT_IUNLOCK(mp);
1803 			goto loop;	/* More work needed */
1804 		}
1805 		mtx_assert(MNT_MTX(mp), MA_OWNED);
1806 		mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED;
1807 		MNT_IUNLOCK(mp);
1808 		suspended = 1;
1809 	} else
1810 		BO_UNLOCK(bo);
1811 	/*
1812 	 * Write back modified superblock.
1813 	 */
1814 	if (fs->fs_fmod != 0 &&
1815 	    (error = ffs_sbupdate(ump, waitfor, suspended)) != 0)
1816 		allerror = error;
1817 	if (ffs_fsfail_cleanup(ump, allerror))
1818 		allerror = 0;
1819 	return (allerror);
1820 }
1821 
1822 int
1823 ffs_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
1824 {
1825 	return (ffs_vgetf(mp, ino, flags, vpp, 0));
1826 }
1827 
1828 int
1829 ffs_vgetf(struct mount *mp,
1830 	ino_t ino,
1831 	int flags,
1832 	struct vnode **vpp,
1833 	int ffs_flags)
1834 {
1835 	struct fs *fs;
1836 	struct inode *ip;
1837 	struct ufsmount *ump;
1838 	struct buf *bp;
1839 	struct vnode *vp;
1840 	daddr_t dbn;
1841 	int error;
1842 
1843 	MPASS((ffs_flags & (FFSV_REPLACE | FFSV_REPLACE_DOOMED)) == 0 ||
1844 	    (flags & LK_EXCLUSIVE) != 0);
1845 
1846 	error = vfs_hash_get(mp, ino, flags, curthread, vpp, NULL, NULL);
1847 	if (error != 0)
1848 		return (error);
1849 	if (*vpp != NULL) {
1850 		if ((ffs_flags & FFSV_REPLACE) == 0 ||
1851 		    ((ffs_flags & FFSV_REPLACE_DOOMED) == 0 ||
1852 		    !VN_IS_DOOMED(*vpp)))
1853 			return (0);
1854 		vgone(*vpp);
1855 		vput(*vpp);
1856 	}
1857 
1858 	/*
1859 	 * We must promote to an exclusive lock for vnode creation.  This
1860 	 * can happen if lookup is passed LOCKSHARED.
1861 	 */
1862 	if ((flags & LK_TYPE_MASK) == LK_SHARED) {
1863 		flags &= ~LK_TYPE_MASK;
1864 		flags |= LK_EXCLUSIVE;
1865 	}
1866 
1867 	/*
1868 	 * We do not lock vnode creation as it is believed to be too
1869 	 * expensive for such rare case as simultaneous creation of vnode
1870 	 * for same ino by different processes. We just allow them to race
1871 	 * and check later to decide who wins. Let the race begin!
1872 	 */
1873 
1874 	ump = VFSTOUFS(mp);
1875 	fs = ump->um_fs;
1876 	ip = uma_zalloc_smr(uma_inode, M_WAITOK | M_ZERO);
1877 
1878 	/* Allocate a new vnode/inode. */
1879 	error = getnewvnode("ufs", mp, fs->fs_magic == FS_UFS1_MAGIC ?
1880 	    &ffs_vnodeops1 : &ffs_vnodeops2, &vp);
1881 	if (error) {
1882 		*vpp = NULL;
1883 		uma_zfree_smr(uma_inode, ip);
1884 		return (error);
1885 	}
1886 	/*
1887 	 * FFS supports recursive locking.
1888 	 */
1889 	lockmgr(vp->v_vnlock, LK_EXCLUSIVE | LK_NOWITNESS, NULL);
1890 	VN_LOCK_AREC(vp);
1891 	vp->v_data = ip;
1892 	vp->v_bufobj.bo_bsize = fs->fs_bsize;
1893 	ip->i_vnode = vp;
1894 	ip->i_ump = ump;
1895 	ip->i_number = ino;
1896 	ip->i_ea_refs = 0;
1897 	ip->i_nextclustercg = -1;
1898 	ip->i_flag = fs->fs_magic == FS_UFS1_MAGIC ? 0 : IN_UFS2;
1899 	ip->i_mode = 0; /* ensure error cases below throw away vnode */
1900 	cluster_init_vn(&ip->i_clusterw);
1901 #ifdef DIAGNOSTIC
1902 	ufs_init_trackers(ip);
1903 #endif
1904 #ifdef QUOTA
1905 	{
1906 		int i;
1907 		for (i = 0; i < MAXQUOTAS; i++)
1908 			ip->i_dquot[i] = NODQUOT;
1909 	}
1910 #endif
1911 
1912 	if (ffs_flags & FFSV_FORCEINSMQ)
1913 		vp->v_vflag |= VV_FORCEINSMQ;
1914 	error = insmntque(vp, mp);
1915 	if (error != 0) {
1916 		uma_zfree_smr(uma_inode, ip);
1917 		*vpp = NULL;
1918 		return (error);
1919 	}
1920 	vp->v_vflag &= ~VV_FORCEINSMQ;
1921 	error = vfs_hash_insert(vp, ino, flags, curthread, vpp, NULL, NULL);
1922 	if (error != 0)
1923 		return (error);
1924 	if (*vpp != NULL) {
1925 		/*
1926 		 * Calls from ffs_valloc() (i.e. FFSV_REPLACE set)
1927 		 * operate on empty inode, which must not be found by
1928 		 * other threads until fully filled.  Vnode for empty
1929 		 * inode must be not re-inserted on the hash by other
1930 		 * thread, after removal by us at the beginning.
1931 		 */
1932 		MPASS((ffs_flags & FFSV_REPLACE) == 0);
1933 		return (0);
1934 	}
1935 	if (I_IS_UFS1(ip))
1936 		ip->i_din1 = uma_zalloc(uma_ufs1, M_WAITOK);
1937 	else
1938 		ip->i_din2 = uma_zalloc(uma_ufs2, M_WAITOK);
1939 
1940 	if ((ffs_flags & FFSV_NEWINODE) != 0) {
1941 		/* New inode, just zero out its contents. */
1942 		if (I_IS_UFS1(ip))
1943 			memset(ip->i_din1, 0, sizeof(struct ufs1_dinode));
1944 		else
1945 			memset(ip->i_din2, 0, sizeof(struct ufs2_dinode));
1946 	} else {
1947 		/* Read the disk contents for the inode, copy into the inode. */
1948 		dbn = fsbtodb(fs, ino_to_fsba(fs, ino));
1949 		error = ffs_breadz(ump, ump->um_devvp, dbn, dbn,
1950 		    (int)fs->fs_bsize, NULL, NULL, 0, NOCRED, 0, NULL, &bp);
1951 		if (error != 0) {
1952 			/*
1953 			 * The inode does not contain anything useful, so it
1954 			 * would be misleading to leave it on its hash chain.
1955 			 * With mode still zero, it will be unlinked and
1956 			 * returned to the free list by vput().
1957 			 */
1958 			vgone(vp);
1959 			vput(vp);
1960 			*vpp = NULL;
1961 			return (error);
1962 		}
1963 		if ((error = ffs_load_inode(bp, ip, fs, ino)) != 0) {
1964 			bqrelse(bp);
1965 			vgone(vp);
1966 			vput(vp);
1967 			*vpp = NULL;
1968 			return (error);
1969 		}
1970 		bqrelse(bp);
1971 	}
1972 	if (DOINGSOFTDEP(vp) && (!fs->fs_ronly ||
1973 	    (ffs_flags & FFSV_FORCEINODEDEP) != 0))
1974 		softdep_load_inodeblock(ip);
1975 	else
1976 		ip->i_effnlink = ip->i_nlink;
1977 
1978 	/*
1979 	 * Initialize the vnode from the inode, check for aliases.
1980 	 * Note that the underlying vnode may have changed.
1981 	 */
1982 	error = ufs_vinit(mp, I_IS_UFS1(ip) ? &ffs_fifoops1 : &ffs_fifoops2,
1983 	    &vp);
1984 	if (error) {
1985 		vgone(vp);
1986 		vput(vp);
1987 		*vpp = NULL;
1988 		return (error);
1989 	}
1990 
1991 	/*
1992 	 * Finish inode initialization.
1993 	 */
1994 	if (vp->v_type != VFIFO) {
1995 		/* FFS supports shared locking for all files except fifos. */
1996 		VN_LOCK_ASHARE(vp);
1997 	}
1998 
1999 	/*
2000 	 * Set up a generation number for this inode if it does not
2001 	 * already have one. This should only happen on old filesystems.
2002 	 */
2003 	if (ip->i_gen == 0) {
2004 		while (ip->i_gen == 0)
2005 			ip->i_gen = arc4random();
2006 		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
2007 			UFS_INODE_SET_FLAG(ip, IN_MODIFIED);
2008 			DIP_SET(ip, i_gen, ip->i_gen);
2009 		}
2010 	}
2011 #ifdef MAC
2012 	if ((mp->mnt_flag & MNT_MULTILABEL) && ip->i_mode) {
2013 		/*
2014 		 * If this vnode is already allocated, and we're running
2015 		 * multi-label, attempt to perform a label association
2016 		 * from the extended attributes on the inode.
2017 		 */
2018 		error = mac_vnode_associate_extattr(mp, vp);
2019 		if (error) {
2020 			/* ufs_inactive will release ip->i_devvp ref. */
2021 			vgone(vp);
2022 			vput(vp);
2023 			*vpp = NULL;
2024 			return (error);
2025 		}
2026 	}
2027 #endif
2028 
2029 	vn_set_state(vp, VSTATE_CONSTRUCTED);
2030 	*vpp = vp;
2031 	return (0);
2032 }
2033 
2034 /*
2035  * File handle to vnode
2036  *
2037  * Have to be really careful about stale file handles:
2038  * - check that the inode number is valid
2039  * - for UFS2 check that the inode number is initialized
2040  * - call ffs_vget() to get the locked inode
2041  * - check for an unallocated inode (i_mode == 0)
2042  * - check that the given client host has export rights and return
2043  *   those rights via. exflagsp and credanonp
2044  */
2045 static int
2046 ffs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
2047 {
2048 	struct ufid *ufhp;
2049 
2050 	ufhp = (struct ufid *)fhp;
2051 	return (ffs_inotovp(mp, ufhp->ufid_ino, ufhp->ufid_gen, flags,
2052 	    vpp, 0));
2053 }
2054 
2055 int
2056 ffs_inotovp(struct mount *mp,
2057 	ino_t ino,
2058 	u_int64_t gen,
2059 	int lflags,
2060 	struct vnode **vpp,
2061 	int ffs_flags)
2062 {
2063 	struct ufsmount *ump;
2064 	struct vnode *nvp;
2065 	struct inode *ip;
2066 	struct fs *fs;
2067 	struct cg *cgp;
2068 	struct buf *bp;
2069 	u_int cg;
2070 	int error;
2071 
2072 	ump = VFSTOUFS(mp);
2073 	fs = ump->um_fs;
2074 	*vpp = NULL;
2075 
2076 	if (ino < UFS_ROOTINO || ino >= fs->fs_ncg * fs->fs_ipg)
2077 		return (ESTALE);
2078 
2079 	/*
2080 	 * Need to check if inode is initialized because UFS2 does lazy
2081 	 * initialization and nfs_fhtovp can offer arbitrary inode numbers.
2082 	 */
2083 	if (fs->fs_magic == FS_UFS2_MAGIC) {
2084 		cg = ino_to_cg(fs, ino);
2085 		error = ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp);
2086 		if (error != 0)
2087 			return (error);
2088 		if (ino >= cg * fs->fs_ipg + cgp->cg_initediblk) {
2089 			brelse(bp);
2090 			return (ESTALE);
2091 		}
2092 		brelse(bp);
2093 	}
2094 
2095 	error = ffs_vgetf(mp, ino, lflags, &nvp, ffs_flags);
2096 	if (error != 0)
2097 		return (error);
2098 
2099 	ip = VTOI(nvp);
2100 	if (ip->i_mode == 0 || ip->i_gen != gen || ip->i_effnlink <= 0) {
2101 		if (ip->i_mode == 0)
2102 			vgone(nvp);
2103 		vput(nvp);
2104 		return (ESTALE);
2105 	}
2106 
2107 	vnode_create_vobject(nvp, DIP(ip, i_size), curthread);
2108 	*vpp = nvp;
2109 	return (0);
2110 }
2111 
2112 /*
2113  * Initialize the filesystem.
2114  */
2115 static int
2116 ffs_init(struct vfsconf *vfsp)
2117 {
2118 
2119 	ffs_susp_initialize();
2120 	softdep_initialize();
2121 	return (ufs_init(vfsp));
2122 }
2123 
2124 /*
2125  * Undo the work of ffs_init().
2126  */
2127 static int
2128 ffs_uninit(struct vfsconf *vfsp)
2129 {
2130 	int ret;
2131 
2132 	ret = ufs_uninit(vfsp);
2133 	softdep_uninitialize();
2134 	ffs_susp_uninitialize();
2135 	taskqueue_drain_all(taskqueue_thread);
2136 	return (ret);
2137 }
2138 
2139 /*
2140  * Structure used to pass information from ffs_sbupdate to its
2141  * helper routine ffs_use_bwrite.
2142  */
2143 struct devfd {
2144 	struct ufsmount	*ump;
2145 	struct buf	*sbbp;
2146 	int		 waitfor;
2147 	int		 suspended;
2148 	int		 error;
2149 };
2150 
2151 /*
2152  * Write a superblock and associated information back to disk.
2153  */
2154 int
2155 ffs_sbupdate(struct ufsmount *ump, int waitfor, int suspended)
2156 {
2157 	struct fs *fs;
2158 	struct buf *sbbp;
2159 	struct devfd devfd;
2160 
2161 	fs = ump->um_fs;
2162 	if (fs->fs_ronly == 1 &&
2163 	    (ump->um_mountp->mnt_flag & (MNT_RDONLY | MNT_UPDATE)) !=
2164 	    (MNT_RDONLY | MNT_UPDATE))
2165 		panic("ffs_sbupdate: write read-only filesystem");
2166 	/*
2167 	 * We use the superblock's buf to serialize calls to ffs_sbupdate().
2168 	 */
2169 	sbbp = getblk(ump->um_devvp, btodb(fs->fs_sblockloc),
2170 	    (int)fs->fs_sbsize, 0, 0, 0);
2171 	/*
2172 	 * Initialize info needed for write function.
2173 	 */
2174 	devfd.ump = ump;
2175 	devfd.sbbp = sbbp;
2176 	devfd.waitfor = waitfor;
2177 	devfd.suspended = suspended;
2178 	devfd.error = 0;
2179 	return (ffs_sbput(&devfd, fs, fs->fs_sblockloc, ffs_use_bwrite));
2180 }
2181 
2182 /*
2183  * Write function for use by filesystem-layer routines.
2184  */
2185 static int
2186 ffs_use_bwrite(void *devfd, off_t loc, void *buf, int size)
2187 {
2188 	struct devfd *devfdp;
2189 	struct ufsmount *ump;
2190 	struct buf *bp;
2191 	struct fs *fs;
2192 	int error;
2193 
2194 	devfdp = devfd;
2195 	ump = devfdp->ump;
2196 	fs = ump->um_fs;
2197 	/*
2198 	 * Writing the superblock summary information.
2199 	 */
2200 	if (loc != fs->fs_sblockloc) {
2201 		bp = getblk(ump->um_devvp, btodb(loc), size, 0, 0, 0);
2202 		bcopy(buf, bp->b_data, (u_int)size);
2203 		if (devfdp->suspended)
2204 			bp->b_flags |= B_VALIDSUSPWRT;
2205 		if (devfdp->waitfor != MNT_WAIT)
2206 			bawrite(bp);
2207 		else if ((error = bwrite(bp)) != 0)
2208 			devfdp->error = error;
2209 		return (0);
2210 	}
2211 	/*
2212 	 * Writing the superblock itself. We need to do special checks for it.
2213 	 */
2214 	bp = devfdp->sbbp;
2215 	if (ffs_fsfail_cleanup(ump, devfdp->error))
2216 		devfdp->error = 0;
2217 	if (devfdp->error != 0) {
2218 		brelse(bp);
2219 		return (devfdp->error);
2220 	}
2221 	if (fs->fs_magic == FS_UFS1_MAGIC && fs->fs_sblockloc != SBLOCK_UFS1 &&
2222 	    (fs->fs_old_flags & FS_FLAGS_UPDATED) == 0) {
2223 		printf("WARNING: %s: correcting fs_sblockloc from %jd to %d\n",
2224 		    fs->fs_fsmnt, fs->fs_sblockloc, SBLOCK_UFS1);
2225 		fs->fs_sblockloc = SBLOCK_UFS1;
2226 	}
2227 	if (fs->fs_magic == FS_UFS2_MAGIC && fs->fs_sblockloc != SBLOCK_UFS2 &&
2228 	    (fs->fs_old_flags & FS_FLAGS_UPDATED) == 0) {
2229 		printf("WARNING: %s: correcting fs_sblockloc from %jd to %d\n",
2230 		    fs->fs_fsmnt, fs->fs_sblockloc, SBLOCK_UFS2);
2231 		fs->fs_sblockloc = SBLOCK_UFS2;
2232 	}
2233 	if (MOUNTEDSOFTDEP(ump->um_mountp))
2234 		softdep_setup_sbupdate(ump, (struct fs *)bp->b_data, bp);
2235 	UFS_LOCK(ump);
2236 	bcopy((caddr_t)fs, bp->b_data, (u_int)fs->fs_sbsize);
2237 	UFS_UNLOCK(ump);
2238 	fs = (struct fs *)bp->b_data;
2239 	fs->fs_fmod = 0;
2240 	ffs_oldfscompat_write(fs, ump);
2241 	fs->fs_si = NULL;
2242 	/* Recalculate the superblock hash */
2243 	fs->fs_ckhash = ffs_calc_sbhash(fs);
2244 	if (devfdp->suspended)
2245 		bp->b_flags |= B_VALIDSUSPWRT;
2246 	if (devfdp->waitfor != MNT_WAIT)
2247 		bawrite(bp);
2248 	else if ((error = bwrite(bp)) != 0)
2249 		devfdp->error = error;
2250 	return (devfdp->error);
2251 }
2252 
2253 static int
2254 ffs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp,
2255 	int attrnamespace, const char *attrname)
2256 {
2257 
2258 #ifdef UFS_EXTATTR
2259 	return (ufs_extattrctl(mp, cmd, filename_vp, attrnamespace,
2260 	    attrname));
2261 #else
2262 	return (vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace,
2263 	    attrname));
2264 #endif
2265 }
2266 
2267 static void
2268 ffs_ifree(struct ufsmount *ump, struct inode *ip)
2269 {
2270 
2271 	if (ump->um_fstype == UFS1 && ip->i_din1 != NULL)
2272 		uma_zfree(uma_ufs1, ip->i_din1);
2273 	else if (ip->i_din2 != NULL)
2274 		uma_zfree(uma_ufs2, ip->i_din2);
2275 	uma_zfree_smr(uma_inode, ip);
2276 }
2277 
2278 static int dobkgrdwrite = 1;
2279 SYSCTL_INT(_debug, OID_AUTO, dobkgrdwrite, CTLFLAG_RW, &dobkgrdwrite, 0,
2280     "Do background writes (honoring the BV_BKGRDWRITE flag)?");
2281 
2282 /*
2283  * Complete a background write started from bwrite.
2284  */
2285 static void
2286 ffs_backgroundwritedone(struct buf *bp)
2287 {
2288 	struct bufobj *bufobj;
2289 	struct buf *origbp;
2290 
2291 #ifdef SOFTUPDATES
2292 	if (!LIST_EMPTY(&bp->b_dep) && (bp->b_ioflags & BIO_ERROR) != 0)
2293 		softdep_handle_error(bp);
2294 #endif
2295 
2296 	/*
2297 	 * Find the original buffer that we are writing.
2298 	 */
2299 	bufobj = bp->b_bufobj;
2300 	BO_LOCK(bufobj);
2301 	if ((origbp = gbincore(bp->b_bufobj, bp->b_lblkno)) == NULL)
2302 		panic("backgroundwritedone: lost buffer");
2303 
2304 	/*
2305 	 * We should mark the cylinder group buffer origbp as
2306 	 * dirty, to not lose the failed write.
2307 	 */
2308 	if ((bp->b_ioflags & BIO_ERROR) != 0)
2309 		origbp->b_vflags |= BV_BKGRDERR;
2310 	BO_UNLOCK(bufobj);
2311 	/*
2312 	 * Process dependencies then return any unfinished ones.
2313 	 */
2314 	if (!LIST_EMPTY(&bp->b_dep) && (bp->b_ioflags & BIO_ERROR) == 0)
2315 		buf_complete(bp);
2316 #ifdef SOFTUPDATES
2317 	if (!LIST_EMPTY(&bp->b_dep))
2318 		softdep_move_dependencies(bp, origbp);
2319 #endif
2320 	/*
2321 	 * This buffer is marked B_NOCACHE so when it is released
2322 	 * by biodone it will be tossed.  Clear B_IOSTARTED in case of error.
2323 	 */
2324 	bp->b_flags |= B_NOCACHE;
2325 	bp->b_flags &= ~(B_CACHE | B_IOSTARTED);
2326 	pbrelvp(bp);
2327 
2328 	/*
2329 	 * Prevent brelse() from trying to keep and re-dirtying bp on
2330 	 * errors. It causes b_bufobj dereference in
2331 	 * bdirty()/reassignbuf(), and b_bufobj was cleared in
2332 	 * pbrelvp() above.
2333 	 */
2334 	if ((bp->b_ioflags & BIO_ERROR) != 0)
2335 		bp->b_flags |= B_INVAL;
2336 	bufdone(bp);
2337 	BO_LOCK(bufobj);
2338 	/*
2339 	 * Clear the BV_BKGRDINPROG flag in the original buffer
2340 	 * and awaken it if it is waiting for the write to complete.
2341 	 * If BV_BKGRDINPROG is not set in the original buffer it must
2342 	 * have been released and re-instantiated - which is not legal.
2343 	 */
2344 	KASSERT((origbp->b_vflags & BV_BKGRDINPROG),
2345 	    ("backgroundwritedone: lost buffer2"));
2346 	origbp->b_vflags &= ~BV_BKGRDINPROG;
2347 	if (origbp->b_vflags & BV_BKGRDWAIT) {
2348 		origbp->b_vflags &= ~BV_BKGRDWAIT;
2349 		wakeup(&origbp->b_xflags);
2350 	}
2351 	BO_UNLOCK(bufobj);
2352 }
2353 
2354 /*
2355  * Write, release buffer on completion.  (Done by iodone
2356  * if async).  Do not bother writing anything if the buffer
2357  * is invalid.
2358  *
2359  * Note that we set B_CACHE here, indicating that buffer is
2360  * fully valid and thus cacheable.  This is true even of NFS
2361  * now so we set it generally.  This could be set either here
2362  * or in biodone() since the I/O is synchronous.  We put it
2363  * here.
2364  */
2365 static int
2366 ffs_bufwrite(struct buf *bp)
2367 {
2368 	struct buf *newbp;
2369 	struct cg *cgp;
2370 
2371 	CTR3(KTR_BUF, "bufwrite(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
2372 	if (bp->b_flags & B_INVAL) {
2373 		brelse(bp);
2374 		return (0);
2375 	}
2376 
2377 	if (!BUF_ISLOCKED(bp))
2378 		panic("bufwrite: buffer is not busy???");
2379 	/*
2380 	 * If a background write is already in progress, delay
2381 	 * writing this block if it is asynchronous. Otherwise
2382 	 * wait for the background write to complete.
2383 	 */
2384 	BO_LOCK(bp->b_bufobj);
2385 	if (bp->b_vflags & BV_BKGRDINPROG) {
2386 		if (bp->b_flags & B_ASYNC) {
2387 			BO_UNLOCK(bp->b_bufobj);
2388 			bdwrite(bp);
2389 			return (0);
2390 		}
2391 		bp->b_vflags |= BV_BKGRDWAIT;
2392 		msleep(&bp->b_xflags, BO_LOCKPTR(bp->b_bufobj), PRIBIO,
2393 		    "bwrbg", 0);
2394 		if (bp->b_vflags & BV_BKGRDINPROG)
2395 			panic("bufwrite: still writing");
2396 	}
2397 	bp->b_vflags &= ~BV_BKGRDERR;
2398 	BO_UNLOCK(bp->b_bufobj);
2399 
2400 	/*
2401 	 * If this buffer is marked for background writing and we
2402 	 * do not have to wait for it, make a copy and write the
2403 	 * copy so as to leave this buffer ready for further use.
2404 	 *
2405 	 * This optimization eats a lot of memory.  If we have a page
2406 	 * or buffer shortfall we can't do it.
2407 	 */
2408 	if (dobkgrdwrite && (bp->b_xflags & BX_BKGRDWRITE) &&
2409 	    (bp->b_flags & B_ASYNC) &&
2410 	    !vm_page_count_severe() &&
2411 	    !buf_dirty_count_severe()) {
2412 		KASSERT(bp->b_iodone == NULL,
2413 		    ("bufwrite: needs chained iodone (%p)", bp->b_iodone));
2414 
2415 		/* get a new block */
2416 		newbp = geteblk(bp->b_bufsize, GB_NOWAIT_BD);
2417 		if (newbp == NULL)
2418 			goto normal_write;
2419 
2420 		KASSERT(buf_mapped(bp), ("Unmapped cg"));
2421 		memcpy(newbp->b_data, bp->b_data, bp->b_bufsize);
2422 		BO_LOCK(bp->b_bufobj);
2423 		bp->b_vflags |= BV_BKGRDINPROG;
2424 		BO_UNLOCK(bp->b_bufobj);
2425 		newbp->b_xflags |=
2426 		    (bp->b_xflags & BX_FSPRIV) | BX_BKGRDMARKER;
2427 		newbp->b_lblkno = bp->b_lblkno;
2428 		newbp->b_blkno = bp->b_blkno;
2429 		newbp->b_offset = bp->b_offset;
2430 		newbp->b_iodone = ffs_backgroundwritedone;
2431 		newbp->b_flags |= B_ASYNC;
2432 		newbp->b_flags &= ~B_INVAL;
2433 		pbgetvp(bp->b_vp, newbp);
2434 
2435 #ifdef SOFTUPDATES
2436 		/*
2437 		 * Move over the dependencies.  If there are rollbacks,
2438 		 * leave the parent buffer dirtied as it will need to
2439 		 * be written again.
2440 		 */
2441 		if (LIST_EMPTY(&bp->b_dep) ||
2442 		    softdep_move_dependencies(bp, newbp) == 0)
2443 			bundirty(bp);
2444 #else
2445 		bundirty(bp);
2446 #endif
2447 
2448 		/*
2449 		 * Initiate write on the copy, release the original.  The
2450 		 * BKGRDINPROG flag prevents it from going away until
2451 		 * the background write completes. We have to recalculate
2452 		 * its check hash in case the buffer gets freed and then
2453 		 * reconstituted from the buffer cache during a later read.
2454 		 */
2455 		if ((bp->b_xflags & BX_CYLGRP) != 0) {
2456 			cgp = (struct cg *)bp->b_data;
2457 			cgp->cg_ckhash = 0;
2458 			cgp->cg_ckhash =
2459 			    calculate_crc32c(~0L, bp->b_data, bp->b_bcount);
2460 		}
2461 		bqrelse(bp);
2462 		bp = newbp;
2463 	} else
2464 		/* Mark the buffer clean */
2465 		bundirty(bp);
2466 
2467 	/* Let the normal bufwrite do the rest for us */
2468 normal_write:
2469 	/*
2470 	 * If we are writing a cylinder group, update its time.
2471 	 */
2472 	if ((bp->b_xflags & BX_CYLGRP) != 0) {
2473 		cgp = (struct cg *)bp->b_data;
2474 		cgp->cg_old_time = cgp->cg_time = time_second;
2475 	}
2476 	return (bufwrite(bp));
2477 }
2478 
2479 static void
2480 ffs_geom_strategy(struct bufobj *bo, struct buf *bp)
2481 {
2482 	struct vnode *vp;
2483 	struct buf *tbp;
2484 	int error, nocopy;
2485 
2486 	/*
2487 	 * This is the bufobj strategy for the private VCHR vnodes
2488 	 * used by FFS to access the underlying storage device.
2489 	 * We override the default bufobj strategy and thus bypass
2490 	 * VOP_STRATEGY() for these vnodes.
2491 	 */
2492 	vp = bo2vnode(bo);
2493 	KASSERT(bp->b_vp == NULL || bp->b_vp->v_type != VCHR ||
2494 	    bp->b_vp->v_rdev == NULL ||
2495 	    bp->b_vp->v_rdev->si_mountpt == NULL ||
2496 	    VFSTOUFS(bp->b_vp->v_rdev->si_mountpt) == NULL ||
2497 	    vp == VFSTOUFS(bp->b_vp->v_rdev->si_mountpt)->um_devvp,
2498 	    ("ffs_geom_strategy() with wrong vp"));
2499 	if (bp->b_iocmd == BIO_WRITE) {
2500 		if ((bp->b_flags & B_VALIDSUSPWRT) == 0 &&
2501 		    bp->b_vp != NULL && bp->b_vp->v_mount != NULL &&
2502 		    (bp->b_vp->v_mount->mnt_kern_flag & MNTK_SUSPENDED) != 0)
2503 			panic("ffs_geom_strategy: bad I/O");
2504 		nocopy = bp->b_flags & B_NOCOPY;
2505 		bp->b_flags &= ~(B_VALIDSUSPWRT | B_NOCOPY);
2506 		if ((vp->v_vflag & VV_COPYONWRITE) && nocopy == 0 &&
2507 		    vp->v_rdev->si_snapdata != NULL) {
2508 			if ((bp->b_flags & B_CLUSTER) != 0) {
2509 				runningbufwakeup(bp);
2510 				TAILQ_FOREACH(tbp, &bp->b_cluster.cluster_head,
2511 					      b_cluster.cluster_entry) {
2512 					error = ffs_copyonwrite(vp, tbp);
2513 					if (error != 0 &&
2514 					    error != EOPNOTSUPP) {
2515 						bp->b_error = error;
2516 						bp->b_ioflags |= BIO_ERROR;
2517 						bp->b_flags &= ~B_BARRIER;
2518 						bufdone(bp);
2519 						return;
2520 					}
2521 				}
2522 				bp->b_runningbufspace = bp->b_bufsize;
2523 				atomic_add_long(&runningbufspace,
2524 					       bp->b_runningbufspace);
2525 			} else {
2526 				error = ffs_copyonwrite(vp, bp);
2527 				if (error != 0 && error != EOPNOTSUPP) {
2528 					bp->b_error = error;
2529 					bp->b_ioflags |= BIO_ERROR;
2530 					bp->b_flags &= ~B_BARRIER;
2531 					bufdone(bp);
2532 					return;
2533 				}
2534 			}
2535 		}
2536 #ifdef SOFTUPDATES
2537 		if ((bp->b_flags & B_CLUSTER) != 0) {
2538 			TAILQ_FOREACH(tbp, &bp->b_cluster.cluster_head,
2539 				      b_cluster.cluster_entry) {
2540 				if (!LIST_EMPTY(&tbp->b_dep))
2541 					buf_start(tbp);
2542 			}
2543 		} else {
2544 			if (!LIST_EMPTY(&bp->b_dep))
2545 				buf_start(bp);
2546 		}
2547 
2548 #endif
2549 		/*
2550 		 * Check for metadata that needs check-hashes and update them.
2551 		 */
2552 		switch (bp->b_xflags & BX_FSPRIV) {
2553 		case BX_CYLGRP:
2554 			((struct cg *)bp->b_data)->cg_ckhash = 0;
2555 			((struct cg *)bp->b_data)->cg_ckhash =
2556 			    calculate_crc32c(~0L, bp->b_data, bp->b_bcount);
2557 			break;
2558 
2559 		case BX_SUPERBLOCK:
2560 		case BX_INODE:
2561 		case BX_INDIR:
2562 		case BX_DIR:
2563 			printf("Check-hash write is unimplemented!!!\n");
2564 			break;
2565 
2566 		case 0:
2567 			break;
2568 
2569 		default:
2570 			printf("multiple buffer types 0x%b\n",
2571 			    (u_int)(bp->b_xflags & BX_FSPRIV),
2572 			    PRINT_UFS_BUF_XFLAGS);
2573 			break;
2574 		}
2575 	}
2576 	if (bp->b_iocmd != BIO_READ && ffs_enxio_enable)
2577 		bp->b_xflags |= BX_CVTENXIO;
2578 	g_vfs_strategy(bo, bp);
2579 }
2580 
2581 int
2582 ffs_own_mount(const struct mount *mp)
2583 {
2584 
2585 	if (mp->mnt_op == &ufs_vfsops)
2586 		return (1);
2587 	return (0);
2588 }
2589 
2590 #ifdef	DDB
2591 #ifdef SOFTUPDATES
2592 
2593 /* defined in ffs_softdep.c */
2594 extern void db_print_ffs(struct ufsmount *ump);
2595 
2596 DB_SHOW_COMMAND(ffs, db_show_ffs)
2597 {
2598 	struct mount *mp;
2599 	struct ufsmount *ump;
2600 
2601 	if (have_addr) {
2602 		ump = VFSTOUFS((struct mount *)addr);
2603 		db_print_ffs(ump);
2604 		return;
2605 	}
2606 
2607 	TAILQ_FOREACH(mp, &mountlist, mnt_list) {
2608 		if (!strcmp(mp->mnt_stat.f_fstypename, ufs_vfsconf.vfc_name))
2609 			db_print_ffs(VFSTOUFS(mp));
2610 	}
2611 }
2612 
2613 #endif	/* SOFTUPDATES */
2614 #endif	/* DDB */
2615