xref: /freebsd/sys/fs/ext2fs/ext2_vfsops.c (revision 8d20be1e22095c27faf8fe8b2f0d089739cc742e)
1 /*-
2  *  modified for EXT2FS support in Lites 1.1
3  *
4  *  Aug 1995, Godmar Back (gback@cs.utah.edu)
5  *  University of Utah, Department of Computer Science
6  */
7 /*-
8  * Copyright (c) 1989, 1991, 1993, 1994
9  *	The Regents of the University of California.  All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)ffs_vfsops.c	8.8 (Berkeley) 4/18/94
36  * $FreeBSD$
37  */
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/namei.h>
42 #include <sys/priv.h>
43 #include <sys/proc.h>
44 #include <sys/kernel.h>
45 #include <sys/vnode.h>
46 #include <sys/mount.h>
47 #include <sys/bio.h>
48 #include <sys/buf.h>
49 #include <sys/conf.h>
50 #include <sys/endian.h>
51 #include <sys/fcntl.h>
52 #include <sys/malloc.h>
53 #include <sys/stat.h>
54 #include <sys/mutex.h>
55 
56 #include <geom/geom.h>
57 #include <geom/geom_vfs.h>
58 
59 #include <fs/ext2fs/ext2_mount.h>
60 #include <fs/ext2fs/inode.h>
61 
62 #include <fs/ext2fs/fs.h>
63 #include <fs/ext2fs/ext2fs.h>
64 #include <fs/ext2fs/ext2_dinode.h>
65 #include <fs/ext2fs/ext2_extern.h>
66 
67 static int	ext2_flushfiles(struct mount *mp, int flags, struct thread *td);
68 static int	ext2_mountfs(struct vnode *, struct mount *);
69 static int	ext2_reload(struct mount *mp, struct thread *td);
70 static int	ext2_sbupdate(struct ext2mount *, int);
71 static int	ext2_cgupdate(struct ext2mount *, int);
72 static vfs_unmount_t		ext2_unmount;
73 static vfs_root_t		ext2_root;
74 static vfs_statfs_t		ext2_statfs;
75 static vfs_sync_t		ext2_sync;
76 static vfs_vget_t		ext2_vget;
77 static vfs_fhtovp_t		ext2_fhtovp;
78 static vfs_mount_t		ext2_mount;
79 
80 MALLOC_DEFINE(M_EXT2NODE, "ext2_node", "EXT2 vnode private part");
81 static MALLOC_DEFINE(M_EXT2MNT, "ext2_mount", "EXT2 mount structure");
82 
83 static struct vfsops ext2fs_vfsops = {
84 	.vfs_fhtovp =		ext2_fhtovp,
85 	.vfs_mount =		ext2_mount,
86 	.vfs_root =		ext2_root,	/* root inode via vget */
87 	.vfs_statfs =		ext2_statfs,
88 	.vfs_sync =		ext2_sync,
89 	.vfs_unmount =		ext2_unmount,
90 	.vfs_vget =		ext2_vget,
91 };
92 
93 VFS_SET(ext2fs_vfsops, ext2fs, 0);
94 
95 static int	ext2_check_sb_compat(struct ext2fs *es, struct cdev *dev,
96 		    int ronly);
97 static int	compute_sb_data(struct vnode * devvp,
98 		    struct ext2fs * es, struct m_ext2fs * fs);
99 
100 static const char *ext2_opts[] = { "acls", "async", "noatime", "noclusterr",
101     "noclusterw", "noexec", "export", "force", "from", "multilabel",
102     "suiddir", "nosymfollow", "sync", "union", NULL };
103 
104 /*
105  * VFS Operations.
106  *
107  * mount system call
108  */
109 static int
110 ext2_mount(struct mount *mp)
111 {
112 	struct vfsoptlist *opts;
113 	struct vnode *devvp;
114 	struct thread *td;
115 	struct ext2mount *ump = NULL;
116 	struct m_ext2fs *fs;
117 	struct nameidata nd, *ndp = &nd;
118 	accmode_t accmode;
119 	char *path, *fspec;
120 	int error, flags, len;
121 
122 	td = curthread;
123 	opts = mp->mnt_optnew;
124 
125 	if (vfs_filteropt(opts, ext2_opts))
126 		return (EINVAL);
127 
128 	vfs_getopt(opts, "fspath", (void **)&path, NULL);
129 	/* Double-check the length of path.. */
130 	if (strlen(path) >= MAXMNTLEN)
131 		return (ENAMETOOLONG);
132 
133 	fspec = NULL;
134 	error = vfs_getopt(opts, "from", (void **)&fspec, &len);
135 	if (!error && fspec[len - 1] != '\0')
136 		return (EINVAL);
137 
138 	/*
139 	 * If updating, check whether changing from read-only to
140 	 * read/write; if there is no device name, that's all we do.
141 	 */
142 	if (mp->mnt_flag & MNT_UPDATE) {
143 		ump = VFSTOEXT2(mp);
144 		fs = ump->um_e2fs;
145 		error = 0;
146 		if (fs->e2fs_ronly == 0 &&
147 		    vfs_flagopt(opts, "ro", NULL, 0)) {
148 			error = VFS_SYNC(mp, MNT_WAIT);
149 			if (error)
150 				return (error);
151 			flags = WRITECLOSE;
152 			if (mp->mnt_flag & MNT_FORCE)
153 				flags |= FORCECLOSE;
154 			error = ext2_flushfiles(mp, flags, td);
155 			if ( error == 0 && fs->e2fs_wasvalid && ext2_cgupdate(ump, MNT_WAIT) == 0) {
156 				fs->e2fs->e2fs_state |= E2FS_ISCLEAN;
157 				ext2_sbupdate(ump, MNT_WAIT);
158 			}
159 			fs->e2fs_ronly = 1;
160 			vfs_flagopt(opts, "ro", &mp->mnt_flag, MNT_RDONLY);
161 			DROP_GIANT();
162 			g_topology_lock();
163 			g_access(ump->um_cp, 0, -1, 0);
164 			g_topology_unlock();
165 			PICKUP_GIANT();
166 		}
167 		if (!error && (mp->mnt_flag & MNT_RELOAD))
168 			error = ext2_reload(mp, td);
169 		if (error)
170 			return (error);
171 		devvp = ump->um_devvp;
172 		if (fs->e2fs_ronly && !vfs_flagopt(opts, "ro", NULL, 0)) {
173 			if (ext2_check_sb_compat(fs->e2fs, devvp->v_rdev, 0))
174 				return (EPERM);
175 
176 			/*
177 			 * If upgrade to read-write by non-root, then verify
178 			 * that user has necessary permissions on the device.
179 			 */
180 			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
181 			error = VOP_ACCESS(devvp, VREAD | VWRITE,
182 			    td->td_ucred, td);
183 			if (error)
184 				error = priv_check(td, PRIV_VFS_MOUNT_PERM);
185 			if (error) {
186 				VOP_UNLOCK(devvp, 0);
187 				return (error);
188 			}
189 			VOP_UNLOCK(devvp, 0);
190 			DROP_GIANT();
191 			g_topology_lock();
192 			error = g_access(ump->um_cp, 0, 1, 0);
193 			g_topology_unlock();
194 			PICKUP_GIANT();
195 			if (error)
196 				return (error);
197 
198 			if ((fs->e2fs->e2fs_state & E2FS_ISCLEAN) == 0 ||
199 			    (fs->e2fs->e2fs_state & E2FS_ERRORS)) {
200 				if (mp->mnt_flag & MNT_FORCE) {
201 					printf(
202 "WARNING: %s was not properly dismounted\n", fs->e2fs_fsmnt);
203 				} else {
204 					printf(
205 "WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
206 					    fs->e2fs_fsmnt);
207 					return (EPERM);
208 				}
209 			}
210 			fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;
211 			(void)ext2_cgupdate(ump, MNT_WAIT);
212 			fs->e2fs_ronly = 0;
213 			MNT_ILOCK(mp);
214 			mp->mnt_flag &= ~MNT_RDONLY;
215 			MNT_IUNLOCK(mp);
216 		}
217 		if (vfs_flagopt(opts, "export", NULL, 0)) {
218 			/* Process export requests in vfs_mount.c. */
219 			return (error);
220 		}
221 	}
222 
223 	/*
224 	 * Not an update, or updating the name: look up the name
225 	 * and verify that it refers to a sensible disk device.
226 	 */
227 	if (fspec == NULL)
228 		return (EINVAL);
229 	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
230 	if ((error = namei(ndp)) != 0)
231 		return (error);
232 	NDFREE(ndp, NDF_ONLY_PNBUF);
233 	devvp = ndp->ni_vp;
234 
235 	if (!vn_isdisk(devvp, &error)) {
236 		vput(devvp);
237 		return (error);
238 	}
239 
240 	/*
241 	 * If mount by non-root, then verify that user has necessary
242 	 * permissions on the device.
243 	 *
244 	 * XXXRW: VOP_ACCESS() enough?
245 	 */
246 	accmode = VREAD;
247 	if ((mp->mnt_flag & MNT_RDONLY) == 0)
248 		accmode |= VWRITE;
249 	error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
250 	if (error)
251 		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
252 	if (error) {
253 		vput(devvp);
254 		return (error);
255 	}
256 
257 	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
258 		error = ext2_mountfs(devvp, mp);
259 	} else {
260 		if (devvp != ump->um_devvp) {
261 			vput(devvp);
262 			return (EINVAL);	/* needs translation */
263 		} else
264 			vput(devvp);
265 	}
266 	if (error) {
267 		vrele(devvp);
268 		return (error);
269 	}
270 	ump = VFSTOEXT2(mp);
271 	fs = ump->um_e2fs;
272 
273 	/*
274 	 * Note that this strncpy() is ok because of a check at the start
275 	 * of ext2_mount().
276 	 */
277 	strncpy(fs->e2fs_fsmnt, path, MAXMNTLEN);
278 	fs->e2fs_fsmnt[MAXMNTLEN - 1] = '\0';
279 	vfs_mountedfrom(mp, fspec);
280 	return (0);
281 }
282 
283 static int
284 ext2_check_sb_compat(struct ext2fs *es, struct cdev *dev, int ronly)
285 {
286 
287 	if (es->e2fs_magic != E2FS_MAGIC) {
288 		printf("ext2fs: %s: wrong magic number %#x (expected %#x)\n",
289 		    devtoname(dev), es->e2fs_magic, E2FS_MAGIC);
290 		return (1);
291 	}
292 	if (es->e2fs_rev > E2FS_REV0) {
293 		if (es->e2fs_features_incompat & ~EXT2F_INCOMPAT_SUPP) {
294 			printf(
295 "WARNING: mount of %s denied due to unsupported optional features\n",
296 			    devtoname(dev));
297 			return (1);
298 		}
299 		if (!ronly &&
300 		    (es->e2fs_features_rocompat & ~EXT2F_ROCOMPAT_SUPP)) {
301 			printf("WARNING: R/W mount of %s denied due to "
302 			    "unsupported optional features\n", devtoname(dev));
303 			return (1);
304 		}
305 	}
306 	return (0);
307 }
308 
309 /*
310  * This computes the fields of the  ext2_sb_info structure from the
311  * data in the ext2_super_block structure read in.
312  */
313 static int
314 compute_sb_data(struct vnode *devvp, struct ext2fs *es,
315     struct m_ext2fs *fs)
316 {
317 	int db_count, error;
318 	int i;
319 	int logic_sb_block = 1;	/* XXX for now */
320 	struct buf *bp;
321 	uint32_t e2fs_descpb;
322 
323 	fs->e2fs_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->e2fs_log_bsize;
324 	fs->e2fs_bsize = 1U << fs->e2fs_bshift;
325 	fs->e2fs_fsbtodb = es->e2fs_log_bsize + 1;
326 	fs->e2fs_qbmask = fs->e2fs_bsize - 1;
327 	fs->e2fs_fsize = EXT2_MIN_FRAG_SIZE << es->e2fs_log_fsize;
328 	if (fs->e2fs_fsize)
329 		fs->e2fs_fpb = fs->e2fs_bsize / fs->e2fs_fsize;
330 	fs->e2fs_bpg = es->e2fs_bpg;
331 	fs->e2fs_fpg = es->e2fs_fpg;
332 	fs->e2fs_ipg = es->e2fs_ipg;
333 	if (es->e2fs_rev == E2FS_REV0) {
334 		fs->e2fs_isize = E2FS_REV0_INODE_SIZE ;
335 	} else {
336 		fs->e2fs_isize = es->e2fs_inode_size;
337 
338 		/*
339 		 * Simple sanity check for superblock inode size value.
340 		 */
341 		if (EXT2_INODE_SIZE(fs) < E2FS_REV0_INODE_SIZE ||
342 		    EXT2_INODE_SIZE(fs) > fs->e2fs_bsize ||
343 		    (fs->e2fs_isize & (fs->e2fs_isize - 1)) != 0) {
344 			printf("ext2fs: invalid inode size %d\n",
345 			    fs->e2fs_isize);
346 			return (EIO);
347 		}
348 	}
349 	/* Check for extra isize in big inodes. */
350 	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_EXTRA_ISIZE) &&
351 	    EXT2_INODE_SIZE(fs) < sizeof(struct ext2fs_dinode)) {
352 		printf("ext2fs: no space for extra inode timestamps\n");
353 		return (EINVAL);
354 	}
355 
356 	fs->e2fs_ipb = fs->e2fs_bsize / EXT2_INODE_SIZE(fs);
357 	fs->e2fs_itpg = fs->e2fs_ipg /fs->e2fs_ipb;
358 	/* s_resuid / s_resgid ? */
359 	fs->e2fs_gcount = (es->e2fs_bcount - es->e2fs_first_dblock +
360 	    EXT2_BLOCKS_PER_GROUP(fs) - 1) / EXT2_BLOCKS_PER_GROUP(fs);
361 	e2fs_descpb = fs->e2fs_bsize / sizeof(struct ext2_gd);
362 	db_count = (fs->e2fs_gcount + e2fs_descpb - 1) / e2fs_descpb;
363 	fs->e2fs_gdbcount = db_count;
364 	fs->e2fs_gd = malloc(db_count * fs->e2fs_bsize,
365 	    M_EXT2MNT, M_WAITOK);
366 	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount *
367 	    sizeof(*fs->e2fs_contigdirs), M_EXT2MNT, M_WAITOK);
368 
369 	/*
370 	 * Adjust logic_sb_block.
371 	 * Godmar thinks: if the blocksize is greater than 1024, then
372 	 * the superblock is logically part of block zero.
373 	 */
374 	if(fs->e2fs_bsize > SBSIZE)
375 		logic_sb_block = 0;
376 	for (i = 0; i < db_count; i++) {
377 		error = bread(devvp ,
378 			 fsbtodb(fs, logic_sb_block + i + 1 ),
379 			fs->e2fs_bsize, NOCRED, &bp);
380 		if (error) {
381 			free(fs->e2fs_gd, M_EXT2MNT);
382 			brelse(bp);
383 			return (error);
384 		}
385 		e2fs_cgload((struct ext2_gd *)bp->b_data,
386 		    &fs->e2fs_gd[
387 			i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
388 		    fs->e2fs_bsize);
389 		brelse(bp);
390 		bp = NULL;
391 	}
392 	fs->e2fs_total_dir = 0;
393 	for (i=0; i < fs->e2fs_gcount; i++){
394 		fs->e2fs_total_dir += fs->e2fs_gd[i].ext2bgd_ndirs;
395 		fs->e2fs_contigdirs[i] = 0;
396 	}
397 	if (es->e2fs_rev == E2FS_REV0 ||
398 	    !EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_LARGEFILE))
399 		fs->e2fs_maxfilesize = 0x7fffffff;
400 	else {
401 		fs->e2fs_maxfilesize = 0xffffffffffff;
402 		if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_HUGE_FILE))
403 			fs->e2fs_maxfilesize = 0x7fffffffffffffff;
404 	}
405 	if (es->e4fs_flags & E2FS_UNSIGNED_HASH) {
406 		fs->e2fs_uhash = 3;
407 	} else if ((es->e4fs_flags & E2FS_SIGNED_HASH) == 0) {
408 #ifdef __CHAR_UNSIGNED__
409 		es->e4fs_flags |= E2FS_UNSIGNED_HASH;
410 		fs->e2fs_uhash = 3;
411 #else
412 		es->e4fs_flags |= E2FS_SIGNED_HASH;
413 #endif
414 	}
415 
416 	return (0);
417 }
418 
419 /*
420  * Reload all incore data for a filesystem (used after running fsck on
421  * the root filesystem and finding things to fix). The filesystem must
422  * be mounted read-only.
423  *
424  * Things to do to update the mount:
425  *	1) invalidate all cached meta-data.
426  *	2) re-read superblock from disk.
427  *	3) invalidate all cluster summary information.
428  *	4) invalidate all inactive vnodes.
429  *	5) invalidate all cached file data.
430  *	6) re-read inode data for all active vnodes.
431  * XXX we are missing some steps, in particular # 3, this has to be reviewed.
432  */
433 static int
434 ext2_reload(struct mount *mp, struct thread *td)
435 {
436 	struct vnode *vp, *mvp, *devvp;
437 	struct inode *ip;
438 	struct buf *bp;
439 	struct ext2fs *es;
440 	struct m_ext2fs *fs;
441 	struct csum *sump;
442 	int error, i;
443 	int32_t *lp;
444 
445 	if ((mp->mnt_flag & MNT_RDONLY) == 0)
446 		return (EINVAL);
447 	/*
448 	 * Step 1: invalidate all cached meta-data.
449 	 */
450 	devvp = VFSTOEXT2(mp)->um_devvp;
451 	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
452 	if (vinvalbuf(devvp, 0, 0, 0) != 0)
453 		panic("ext2_reload: dirty1");
454 	VOP_UNLOCK(devvp, 0);
455 
456 	/*
457 	 * Step 2: re-read superblock from disk.
458 	 * constants have been adjusted for ext2
459 	 */
460 	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
461 		return (error);
462 	es = (struct ext2fs *)bp->b_data;
463 	if (ext2_check_sb_compat(es, devvp->v_rdev, 0) != 0) {
464 		brelse(bp);
465 		return (EIO);		/* XXX needs translation */
466 	}
467 	fs = VFSTOEXT2(mp)->um_e2fs;
468 	bcopy(bp->b_data, fs->e2fs, sizeof(struct ext2fs));
469 
470 	if((error = compute_sb_data(devvp, es, fs)) != 0) {
471 		brelse(bp);
472 		return (error);
473 	}
474 #ifdef UNKLAR
475 	if (fs->fs_sbsize < SBSIZE)
476 		bp->b_flags |= B_INVAL;
477 #endif
478 	brelse(bp);
479 
480 	/*
481 	 * Step 3: invalidate all cluster summary information.
482 	 */
483 	if (fs->e2fs_contigsumsize > 0) {
484 		lp = fs->e2fs_maxcluster;
485 		sump = fs->e2fs_clustersum;
486 		for (i = 0; i < fs->e2fs_gcount; i++, sump++) {
487 			*lp++ = fs->e2fs_contigsumsize;
488 			sump->cs_init = 0;
489 			bzero(sump->cs_sum, fs->e2fs_contigsumsize + 1);
490 		}
491 	}
492 
493 loop:
494 	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
495 		/*
496 		 * Step 4: invalidate all cached file data.
497 		 */
498 		if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
499 			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
500 			goto loop;
501 		}
502 		if (vinvalbuf(vp, 0, 0, 0))
503 			panic("ext2_reload: dirty2");
504 
505 		/*
506 		 * Step 5: re-read inode data for all active vnodes.
507 		 */
508 		ip = VTOI(vp);
509 		error = bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
510 		    (int)fs->e2fs_bsize, NOCRED, &bp);
511 		if (error) {
512 			VOP_UNLOCK(vp, 0);
513 			vrele(vp);
514 			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
515 			return (error);
516 		}
517 		ext2_ei2i((struct ext2fs_dinode *) ((char *)bp->b_data +
518 		    EXT2_INODE_SIZE(fs) * ino_to_fsbo(fs, ip->i_number)), ip);
519 		brelse(bp);
520 		VOP_UNLOCK(vp, 0);
521 		vrele(vp);
522 	}
523 	return (0);
524 }
525 
526 /*
527  * Common code for mount and mountroot.
528  */
529 static int
530 ext2_mountfs(struct vnode *devvp, struct mount *mp)
531 {
532 	struct ext2mount *ump;
533 	struct buf *bp;
534 	struct m_ext2fs *fs;
535 	struct ext2fs *es;
536 	struct cdev *dev = devvp->v_rdev;
537 	struct g_consumer *cp;
538 	struct bufobj *bo;
539 	struct csum *sump;
540 	int error;
541 	int ronly;
542 	int i, size;
543 	int32_t *lp;
544 	int32_t e2fs_maxcontig;
545 
546 	ronly = vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0);
547 	/* XXX: use VOP_ACESS to check FS perms */
548 	DROP_GIANT();
549 	g_topology_lock();
550 	error = g_vfs_open(devvp, &cp, "ext2fs", ronly ? 0 : 1);
551 	g_topology_unlock();
552 	PICKUP_GIANT();
553 	VOP_UNLOCK(devvp, 0);
554 	if (error)
555 		return (error);
556 
557 	/* XXX: should we check for some sectorsize or 512 instead? */
558 	if (((SBSIZE % cp->provider->sectorsize) != 0) ||
559 	    (SBSIZE < cp->provider->sectorsize)) {
560 		DROP_GIANT();
561 		g_topology_lock();
562 		g_vfs_close(cp);
563 		g_topology_unlock();
564 		PICKUP_GIANT();
565 		return (EINVAL);
566 	}
567 
568 	bo = &devvp->v_bufobj;
569 	bo->bo_private = cp;
570 	bo->bo_ops = g_vfs_bufops;
571 	if (devvp->v_rdev->si_iosize_max != 0)
572 		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
573 	if (mp->mnt_iosize_max > MAXPHYS)
574 		mp->mnt_iosize_max = MAXPHYS;
575 
576 	bp = NULL;
577 	ump = NULL;
578 	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
579 		goto out;
580 	es = (struct ext2fs *)bp->b_data;
581 	if (ext2_check_sb_compat(es, dev, ronly) != 0) {
582 		error = EINVAL;		/* XXX needs translation */
583 		goto out;
584 	}
585 	if ((es->e2fs_state & E2FS_ISCLEAN) == 0 ||
586 	    (es->e2fs_state & E2FS_ERRORS)) {
587 		if (ronly || (mp->mnt_flag & MNT_FORCE)) {
588 			printf(
589 "WARNING: Filesystem was not properly dismounted\n");
590 		} else {
591 			printf(
592 "WARNING: R/W mount denied.  Filesystem is not clean - run fsck\n");
593 			error = EPERM;
594 			goto out;
595 		}
596 	}
597 	ump = malloc(sizeof(*ump), M_EXT2MNT, M_WAITOK | M_ZERO);
598 
599 	/*
600 	 * I don't know whether this is the right strategy. Note that
601 	 * we dynamically allocate both an ext2_sb_info and an ext2_super_block
602 	 * while Linux keeps the super block in a locked buffer.
603 	 */
604 	ump->um_e2fs = malloc(sizeof(struct m_ext2fs),
605 		M_EXT2MNT, M_WAITOK);
606 	ump->um_e2fs->e2fs = malloc(sizeof(struct ext2fs),
607 		M_EXT2MNT, M_WAITOK);
608 	mtx_init(EXT2_MTX(ump), "EXT2FS", "EXT2FS Lock", MTX_DEF);
609 	bcopy(es, ump->um_e2fs->e2fs, (u_int)sizeof(struct ext2fs));
610 	if ((error = compute_sb_data(devvp, ump->um_e2fs->e2fs, ump->um_e2fs)))
611 		goto out;
612 
613 	/*
614 	 * Calculate the maximum contiguous blocks and size of cluster summary
615 	 * array.  In FFS this is done by newfs; however, the superblock
616 	 * in ext2fs doesn't have these variables, so we can calculate
617 	 * them here.
618 	 */
619 	e2fs_maxcontig = MAX(1, MAXPHYS / ump->um_e2fs->e2fs_bsize);
620 	ump->um_e2fs->e2fs_contigsumsize = MIN(e2fs_maxcontig, EXT2_MAXCONTIG);
621 	if (ump->um_e2fs->e2fs_contigsumsize > 0) {
622 		size = ump->um_e2fs->e2fs_gcount * sizeof(int32_t);
623 		ump->um_e2fs->e2fs_maxcluster = malloc(size, M_EXT2MNT, M_WAITOK);
624 		size = ump->um_e2fs->e2fs_gcount * sizeof(struct csum);
625 		ump->um_e2fs->e2fs_clustersum = malloc(size, M_EXT2MNT, M_WAITOK);
626 		lp = ump->um_e2fs->e2fs_maxcluster;
627 		sump = ump->um_e2fs->e2fs_clustersum;
628 		for (i = 0; i < ump->um_e2fs->e2fs_gcount; i++, sump++) {
629 			*lp++ = ump->um_e2fs->e2fs_contigsumsize;
630 			sump->cs_init = 0;
631 			sump->cs_sum = malloc((ump->um_e2fs->e2fs_contigsumsize + 1) *
632 			    sizeof(int32_t), M_EXT2MNT, M_WAITOK | M_ZERO);
633 		}
634 	}
635 
636 	brelse(bp);
637 	bp = NULL;
638 	fs = ump->um_e2fs;
639 	fs->e2fs_ronly = ronly;	/* ronly is set according to mnt_flags */
640 
641 	/*
642 	 * If the fs is not mounted read-only, make sure the super block is
643 	 * always written back on a sync().
644 	 */
645 	fs->e2fs_wasvalid = fs->e2fs->e2fs_state & E2FS_ISCLEAN ? 1 : 0;
646 	if (ronly == 0) {
647 		fs->e2fs_fmod = 1;		/* mark it modified */
648 		fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;	/* set fs invalid */
649 	}
650 	mp->mnt_data = ump;
651 	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
652 	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
653 	mp->mnt_maxsymlinklen = EXT2_MAXSYMLINKLEN;
654 	MNT_ILOCK(mp);
655 	mp->mnt_flag |= MNT_LOCAL;
656 	MNT_IUNLOCK(mp);
657 	ump->um_mountp = mp;
658 	ump->um_dev = dev;
659 	ump->um_devvp = devvp;
660 	ump->um_bo = &devvp->v_bufobj;
661 	ump->um_cp = cp;
662 
663 	/*
664 	 * Setting those two parameters allowed us to use
665 	 * ufs_bmap w/o changse!
666 	 */
667 	ump->um_nindir = EXT2_ADDR_PER_BLOCK(fs);
668 	ump->um_bptrtodb = fs->e2fs->e2fs_log_bsize + 1;
669 	ump->um_seqinc = EXT2_FRAGS_PER_BLOCK(fs);
670 	if (ronly == 0)
671 		ext2_sbupdate(ump, MNT_WAIT);
672 	/*
673 	 * Initialize filesystem stat information in mount struct.
674 	 */
675 	MNT_ILOCK(mp);
676  	mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED;
677 	MNT_IUNLOCK(mp);
678 	return (0);
679 out:
680 	if (bp)
681 		brelse(bp);
682 	if (cp != NULL) {
683 		DROP_GIANT();
684 		g_topology_lock();
685 		g_vfs_close(cp);
686 		g_topology_unlock();
687 		PICKUP_GIANT();
688 	}
689 	if (ump) {
690 	  	mtx_destroy(EXT2_MTX(ump));
691 		free(ump->um_e2fs->e2fs_gd, M_EXT2MNT);
692 		free(ump->um_e2fs->e2fs_contigdirs, M_EXT2MNT);
693 		free(ump->um_e2fs->e2fs, M_EXT2MNT);
694 		free(ump->um_e2fs, M_EXT2MNT);
695 		free(ump, M_EXT2MNT);
696 		mp->mnt_data = NULL;
697 	}
698 	return (error);
699 }
700 
701 /*
702  * Unmount system call.
703  */
704 static int
705 ext2_unmount(struct mount *mp, int mntflags)
706 {
707 	struct ext2mount *ump;
708 	struct m_ext2fs *fs;
709 	struct csum *sump;
710 	int error, flags, i, ronly;
711 
712 	flags = 0;
713 	if (mntflags & MNT_FORCE) {
714 		if (mp->mnt_flag & MNT_ROOTFS)
715 			return (EINVAL);
716 		flags |= FORCECLOSE;
717 	}
718 	if ((error = ext2_flushfiles(mp, flags, curthread)) != 0)
719 		return (error);
720 	ump = VFSTOEXT2(mp);
721 	fs = ump->um_e2fs;
722 	ronly = fs->e2fs_ronly;
723 	if (ronly == 0 && ext2_cgupdate(ump, MNT_WAIT) == 0) {
724 		if (fs->e2fs_wasvalid)
725  			fs->e2fs->e2fs_state |= E2FS_ISCLEAN;
726  		ext2_sbupdate(ump, MNT_WAIT);
727 	}
728 
729 	DROP_GIANT();
730 	g_topology_lock();
731 	g_vfs_close(ump->um_cp);
732 	g_topology_unlock();
733 	PICKUP_GIANT();
734 	vrele(ump->um_devvp);
735 	sump = fs->e2fs_clustersum;
736 	for (i = 0; i < fs->e2fs_gcount; i++, sump++)
737 		free(sump->cs_sum, M_EXT2MNT);
738 	free(fs->e2fs_clustersum, M_EXT2MNT);
739 	free(fs->e2fs_maxcluster, M_EXT2MNT);
740 	free(fs->e2fs_gd, M_EXT2MNT);
741 	free(fs->e2fs_contigdirs, M_EXT2MNT);
742 	free(fs->e2fs, M_EXT2MNT);
743 	free(fs, M_EXT2MNT);
744 	free(ump, M_EXT2MNT);
745 	mp->mnt_data = NULL;
746 	MNT_ILOCK(mp);
747 	mp->mnt_flag &= ~MNT_LOCAL;
748 	MNT_IUNLOCK(mp);
749 	return (error);
750 }
751 
752 /*
753  * Flush out all the files in a filesystem.
754  */
755 static int
756 ext2_flushfiles(struct mount *mp, int flags, struct thread *td)
757 {
758 	int error;
759 
760 	error = vflush(mp, 0, flags, td);
761 	return (error);
762 }
763 /*
764  * Get filesystem statistics.
765  */
766 int
767 ext2_statfs(struct mount *mp, struct statfs *sbp)
768 {
769 	struct ext2mount *ump;
770 	struct m_ext2fs *fs;
771 	uint32_t overhead, overhead_per_group, ngdb;
772 	int i, ngroups;
773 
774 	ump = VFSTOEXT2(mp);
775 	fs = ump->um_e2fs;
776 	if (fs->e2fs->e2fs_magic != E2FS_MAGIC)
777 		panic("ext2_statfs");
778 
779 	/*
780 	 * Compute the overhead (FS structures)
781 	 */
782 	overhead_per_group =
783 	    1 /* block bitmap */ +
784 	    1 /* inode bitmap */ +
785 	    fs->e2fs_itpg;
786 	overhead = fs->e2fs->e2fs_first_dblock +
787 	    fs->e2fs_gcount * overhead_per_group;
788 	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
789 	    fs->e2fs->e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) {
790 		for (i = 0, ngroups = 0; i < fs->e2fs_gcount; i++) {
791 			if (cg_has_sb(i))
792 				ngroups++;
793 		}
794 	} else {
795 		ngroups = fs->e2fs_gcount;
796 	}
797 	ngdb = fs->e2fs_gdbcount;
798 	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
799 	    fs->e2fs->e2fs_features_compat & EXT2F_COMPAT_RESIZE)
800 		ngdb += fs->e2fs->e2fs_reserved_ngdb;
801 	overhead += ngroups * (1 /* superblock */ + ngdb);
802 
803 	sbp->f_bsize = EXT2_FRAG_SIZE(fs);
804 	sbp->f_iosize = EXT2_BLOCK_SIZE(fs);
805 	sbp->f_blocks = fs->e2fs->e2fs_bcount - overhead;
806 	sbp->f_bfree = fs->e2fs->e2fs_fbcount;
807 	sbp->f_bavail = sbp->f_bfree - fs->e2fs->e2fs_rbcount;
808 	sbp->f_files = fs->e2fs->e2fs_icount;
809 	sbp->f_ffree = fs->e2fs->e2fs_ficount;
810 	return (0);
811 }
812 
813 /*
814  * Go through the disk queues to initiate sandbagged IO;
815  * go through the inodes to write those that have been modified;
816  * initiate the writing of the super block if it has been modified.
817  *
818  * Note: we are always called with the filesystem marked `MPBUSY'.
819  */
820 static int
821 ext2_sync(struct mount *mp, int waitfor)
822 {
823 	struct vnode *mvp, *vp;
824 	struct thread *td;
825 	struct inode *ip;
826 	struct ext2mount *ump = VFSTOEXT2(mp);
827 	struct m_ext2fs *fs;
828 	int error, allerror = 0;
829 
830 	td = curthread;
831 	fs = ump->um_e2fs;
832 	if (fs->e2fs_fmod != 0 && fs->e2fs_ronly != 0) {		/* XXX */
833 		printf("fs = %s\n", fs->e2fs_fsmnt);
834 		panic("ext2_sync: rofs mod");
835 	}
836 
837 	/*
838 	 * Write back each (modified) inode.
839 	 */
840 loop:
841 	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
842 		if (vp->v_type == VNON) {
843 			VI_UNLOCK(vp);
844 			continue;
845 		}
846 		ip = VTOI(vp);
847 		if ((ip->i_flag &
848 		    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
849 		    (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
850 		    waitfor == MNT_LAZY)) {
851 			VI_UNLOCK(vp);
852 			continue;
853 		}
854 		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
855 		if (error) {
856 			if (error == ENOENT) {
857 				MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
858 				goto loop;
859 			}
860 			continue;
861 		}
862 		if ((error = VOP_FSYNC(vp, waitfor, td)) != 0)
863 			allerror = error;
864 		VOP_UNLOCK(vp, 0);
865 		vrele(vp);
866 	}
867 
868 	/*
869 	 * Force stale filesystem control information to be flushed.
870 	 */
871 	if (waitfor != MNT_LAZY) {
872 		vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
873 		if ((error = VOP_FSYNC(ump->um_devvp, waitfor, td)) != 0)
874 			allerror = error;
875 		VOP_UNLOCK(ump->um_devvp, 0);
876 	}
877 
878 	/*
879 	 * Write back modified superblock.
880 	 */
881 	if (fs->e2fs_fmod != 0) {
882 		fs->e2fs_fmod = 0;
883 		fs->e2fs->e2fs_wtime = time_second;
884 		if ((error = ext2_cgupdate(ump, waitfor)) != 0)
885 			allerror = error;
886 	}
887 	return (allerror);
888 }
889 
890 /*
891  * Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
892  * in from disk.  If it is in core, wait for the lock bit to clear, then
893  * return the inode locked.  Detection and handling of mount points must be
894  * done by the calling routine.
895  */
896 static int
897 ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
898 {
899 	struct m_ext2fs *fs;
900 	struct inode *ip;
901 	struct ext2mount *ump;
902 	struct buf *bp;
903 	struct vnode *vp;
904 	struct cdev *dev;
905 	struct thread *td;
906 	int i, error;
907 	int used_blocks;
908 
909 	td = curthread;
910 	error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
911 	if (error || *vpp != NULL)
912 		return (error);
913 
914 	ump = VFSTOEXT2(mp);
915 	dev = ump->um_dev;
916 	ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
917 
918 	/* Allocate a new vnode/inode. */
919 	if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
920 		*vpp = NULL;
921 		free(ip, M_EXT2NODE);
922 		return (error);
923 	}
924 	vp->v_data = ip;
925 	ip->i_vnode = vp;
926 	ip->i_e2fs = fs = ump->um_e2fs;
927 	ip->i_ump  = ump;
928 	ip->i_number = ino;
929 
930 	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
931 	error = insmntque(vp, mp);
932 	if (error != 0) {
933 		free(ip, M_EXT2NODE);
934 		*vpp = NULL;
935 		return (error);
936 	}
937 	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
938 	if (error || *vpp != NULL)
939 		return (error);
940 
941 	/* Read in the disk contents for the inode, copy into the inode. */
942 	if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
943 	    (int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
944 		/*
945 		 * The inode does not contain anything useful, so it would
946 		 * be misleading to leave it on its hash chain. With mode
947 		 * still zero, it will be unlinked and returned to the free
948 		 * list by vput().
949 		 */
950 		brelse(bp);
951 		vput(vp);
952 		*vpp = NULL;
953 		return (error);
954 	}
955 	/* convert ext2 inode to dinode */
956 	ext2_ei2i((struct ext2fs_dinode *) ((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
957 			ino_to_fsbo(fs, ino)), ip);
958 	ip->i_block_group = ino_to_cg(fs, ino);
959 	ip->i_next_alloc_block = 0;
960 	ip->i_next_alloc_goal = 0;
961 
962 	/*
963 	 * Now we want to make sure that block pointers for unused
964 	 * blocks are zeroed out - ext2_balloc depends on this
965 	 * although for regular files and directories only
966 	 *
967 	 * If EXT4_EXTENTS flag is enabled, unused blocks aren't
968 	 * zeroed out because we could corrupt the extent tree.
969 	 */
970 	if (!(ip->i_flags & EXT4_EXTENTS) &&
971 	    (S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode))) {
972 		used_blocks = (ip->i_size+fs->e2fs_bsize-1) / fs->e2fs_bsize;
973 		for (i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
974 			ip->i_db[i] = 0;
975 	}
976 /*
977 	ext2_print_inode(ip);
978 */
979 	bqrelse(bp);
980 
981 	/*
982 	 * Initialize the vnode from the inode, check for aliases.
983 	 * Note that the underlying vnode may have changed.
984 	 */
985 	if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
986 		vput(vp);
987 		*vpp = NULL;
988 		return (error);
989 	}
990 
991 	/*
992 	 * Finish inode initialization.
993 	 */
994 
995 	/*
996 	 * Set up a generation number for this inode if it does not
997 	 * already have one. This should only happen on old filesystems.
998 	 */
999 	if (ip->i_gen == 0) {
1000 		ip->i_gen = random() + 1;
1001 		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
1002 			ip->i_flag |= IN_MODIFIED;
1003 	}
1004 	*vpp = vp;
1005 	return (0);
1006 }
1007 
1008 /*
1009  * File handle to vnode
1010  *
1011  * Have to be really careful about stale file handles:
1012  * - check that the inode number is valid
1013  * - call ext2_vget() to get the locked inode
1014  * - check for an unallocated inode (i_mode == 0)
1015  * - check that the given client host has export rights and return
1016  *   those rights via. exflagsp and credanonp
1017  */
1018 static int
1019 ext2_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
1020 {
1021 	struct inode *ip;
1022 	struct ufid *ufhp;
1023 	struct vnode *nvp;
1024 	struct m_ext2fs *fs;
1025 	int error;
1026 
1027 	ufhp = (struct ufid *)fhp;
1028 	fs = VFSTOEXT2(mp)->um_e2fs;
1029 	if (ufhp->ufid_ino < EXT2_ROOTINO ||
1030 	    ufhp->ufid_ino > fs->e2fs_gcount * fs->e2fs->e2fs_ipg)
1031 		return (ESTALE);
1032 
1033 	error = VFS_VGET(mp, ufhp->ufid_ino, LK_EXCLUSIVE, &nvp);
1034 	if (error) {
1035 		*vpp = NULLVP;
1036 		return (error);
1037 	}
1038 	ip = VTOI(nvp);
1039 	if (ip->i_mode == 0 ||
1040 	    ip->i_gen != ufhp->ufid_gen || ip->i_nlink <= 0) {
1041 		vput(nvp);
1042 		*vpp = NULLVP;
1043 		return (ESTALE);
1044 	}
1045 	*vpp = nvp;
1046 	vnode_create_vobject(*vpp, 0, curthread);
1047 	return (0);
1048 }
1049 
1050 /*
1051  * Write a superblock and associated information back to disk.
1052  */
1053 static int
1054 ext2_sbupdate(struct ext2mount *mp, int waitfor)
1055 {
1056 	struct m_ext2fs *fs = mp->um_e2fs;
1057 	struct ext2fs *es = fs->e2fs;
1058 	struct buf *bp;
1059 	int error = 0;
1060 
1061 	bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0, 0);
1062 	bcopy((caddr_t)es, bp->b_data, (u_int)sizeof(struct ext2fs));
1063 	if (waitfor == MNT_WAIT)
1064 		error = bwrite(bp);
1065 	else
1066 		bawrite(bp);
1067 
1068 	/*
1069 	 * The buffers for group descriptors, inode bitmaps and block bitmaps
1070 	 * are not busy at this point and are (hopefully) written by the
1071 	 * usual sync mechanism. No need to write them here.
1072 	 */
1073 	return (error);
1074 }
1075 int
1076 ext2_cgupdate(struct ext2mount *mp, int waitfor)
1077 {
1078 	struct m_ext2fs *fs = mp->um_e2fs;
1079 	struct buf *bp;
1080 	int i, error = 0, allerror = 0;
1081 
1082 	allerror = ext2_sbupdate(mp, waitfor);
1083 	for (i = 0; i < fs->e2fs_gdbcount; i++) {
1084 		bp = getblk(mp->um_devvp, fsbtodb(fs,
1085 		    fs->e2fs->e2fs_first_dblock +
1086 		    1 /* superblock */ + i), fs->e2fs_bsize, 0, 0, 0);
1087 		e2fs_cgsave(&fs->e2fs_gd[
1088 		    i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
1089 		    (struct ext2_gd *)bp->b_data, fs->e2fs_bsize);
1090 		if (waitfor == MNT_WAIT)
1091 			error = bwrite(bp);
1092 		else
1093 			bawrite(bp);
1094 	}
1095 
1096 	if (!allerror && error)
1097 		allerror = error;
1098 	return (allerror);
1099 }
1100 /*
1101  * Return the root of a filesystem.
1102  */
1103 static int
1104 ext2_root(struct mount *mp, int flags, struct vnode **vpp)
1105 {
1106 	struct vnode *nvp;
1107 	int error;
1108 
1109 	error = VFS_VGET(mp, EXT2_ROOTINO, LK_EXCLUSIVE, &nvp);
1110 	if (error)
1111 		return (error);
1112 	*vpp = nvp;
1113 	return (0);
1114 }
1115