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: stable/11/sys/fs/ext2fs/ext2_vfsops.c 350385 2019-07-27 19:29:28Z fsu $
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
67static int	ext2_flushfiles(struct mount *mp, int flags, struct thread *td);
68static int	ext2_mountfs(struct vnode *, struct mount *);
69static int	ext2_reload(struct mount *mp, struct thread *td);
70static int	ext2_sbupdate(struct ext2mount *, int);
71static int	ext2_cgupdate(struct ext2mount *, int);
72static vfs_unmount_t		ext2_unmount;
73static vfs_root_t		ext2_root;
74static vfs_statfs_t		ext2_statfs;
75static vfs_sync_t		ext2_sync;
76static vfs_vget_t		ext2_vget;
77static vfs_fhtovp_t		ext2_fhtovp;
78static vfs_mount_t		ext2_mount;
79
80MALLOC_DEFINE(M_EXT2NODE, "ext2_node", "EXT2 vnode private part");
81static MALLOC_DEFINE(M_EXT2MNT, "ext2_mount", "EXT2 mount structure");
82
83static 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
93VFS_SET(ext2fs_vfsops, ext2fs, 0);
94
95static int	ext2_check_sb_compat(struct ext2fs *es, struct cdev *dev,
96		    int ronly);
97static int	compute_sb_data(struct vnode * devvp,
98		    struct ext2fs * es, struct m_ext2fs * fs);
99
100static 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 */
109static int
110ext2_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			g_topology_lock();
162			g_access(ump->um_cp, 0, -1, 0);
163			g_topology_unlock();
164		}
165		if (!error && (mp->mnt_flag & MNT_RELOAD))
166			error = ext2_reload(mp, td);
167		if (error)
168			return (error);
169		devvp = ump->um_devvp;
170		if (fs->e2fs_ronly && !vfs_flagopt(opts, "ro", NULL, 0)) {
171			if (ext2_check_sb_compat(fs->e2fs, devvp->v_rdev, 0))
172				return (EPERM);
173
174			/*
175			 * If upgrade to read-write by non-root, then verify
176			 * that user has necessary permissions on the device.
177			 */
178			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
179			error = VOP_ACCESS(devvp, VREAD | VWRITE,
180			    td->td_ucred, td);
181			if (error)
182				error = priv_check(td, PRIV_VFS_MOUNT_PERM);
183			if (error) {
184				VOP_UNLOCK(devvp, 0);
185				return (error);
186			}
187			VOP_UNLOCK(devvp, 0);
188			g_topology_lock();
189			error = g_access(ump->um_cp, 0, 1, 0);
190			g_topology_unlock();
191			if (error)
192				return (error);
193
194			if ((fs->e2fs->e2fs_state & E2FS_ISCLEAN) == 0 ||
195			    (fs->e2fs->e2fs_state & E2FS_ERRORS)) {
196				if (mp->mnt_flag & MNT_FORCE) {
197					printf(
198"WARNING: %s was not properly dismounted\n", fs->e2fs_fsmnt);
199				} else {
200					printf(
201"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
202					    fs->e2fs_fsmnt);
203					return (EPERM);
204				}
205			}
206			fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;
207			(void)ext2_cgupdate(ump, MNT_WAIT);
208			fs->e2fs_ronly = 0;
209			MNT_ILOCK(mp);
210			mp->mnt_flag &= ~MNT_RDONLY;
211			MNT_IUNLOCK(mp);
212		}
213		if (vfs_flagopt(opts, "export", NULL, 0)) {
214			/* Process export requests in vfs_mount.c. */
215			return (error);
216		}
217	}
218
219	/*
220	 * Not an update, or updating the name: look up the name
221	 * and verify that it refers to a sensible disk device.
222	 */
223	if (fspec == NULL)
224		return (EINVAL);
225	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
226	if ((error = namei(ndp)) != 0)
227		return (error);
228	NDFREE(ndp, NDF_ONLY_PNBUF);
229	devvp = ndp->ni_vp;
230
231	if (!vn_isdisk(devvp, &error)) {
232		vput(devvp);
233		return (error);
234	}
235
236	/*
237	 * If mount by non-root, then verify that user has necessary
238	 * permissions on the device.
239	 *
240	 * XXXRW: VOP_ACCESS() enough?
241	 */
242	accmode = VREAD;
243	if ((mp->mnt_flag & MNT_RDONLY) == 0)
244		accmode |= VWRITE;
245	error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
246	if (error)
247		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
248	if (error) {
249		vput(devvp);
250		return (error);
251	}
252
253	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
254		error = ext2_mountfs(devvp, mp);
255	} else {
256		if (devvp != ump->um_devvp) {
257			vput(devvp);
258			return (EINVAL);	/* needs translation */
259		} else
260			vput(devvp);
261	}
262	if (error) {
263		vrele(devvp);
264		return (error);
265	}
266	ump = VFSTOEXT2(mp);
267	fs = ump->um_e2fs;
268
269	/*
270	 * Note that this strncpy() is ok because of a check at the start
271	 * of ext2_mount().
272	 */
273	strncpy(fs->e2fs_fsmnt, path, MAXMNTLEN);
274	fs->e2fs_fsmnt[MAXMNTLEN - 1] = '\0';
275	vfs_mountedfrom(mp, fspec);
276	return (0);
277}
278
279static int
280ext2_check_sb_compat(struct ext2fs *es, struct cdev *dev, int ronly)
281{
282	uint32_t i, mask;
283
284	if (es->e2fs_magic != E2FS_MAGIC) {
285		printf("ext2fs: %s: wrong magic number %#x (expected %#x)\n",
286		    devtoname(dev), es->e2fs_magic, E2FS_MAGIC);
287		return (1);
288	}
289	if (es->e2fs_rev > E2FS_REV0) {
290		mask = es->e2fs_features_incompat & ~(EXT2F_INCOMPAT_SUPP |
291		    EXT4F_RO_INCOMPAT_SUPP);
292		if (mask) {
293			printf("WARNING: mount of %s denied due to "
294			    "unsupported optional features:\n", devtoname(dev));
295			for (i = 0;
296			    i < sizeof(incompat)/sizeof(struct ext2_feature);
297			    i++)
298				if (mask & incompat[i].mask)
299					printf("%s ", incompat[i].name);
300			printf("\n");
301			return (1);
302		}
303		mask = es->e2fs_features_rocompat & ~EXT2F_ROCOMPAT_SUPP;
304		if (!ronly && mask) {
305			printf("WARNING: R/W mount of %s denied due to "
306			    "unsupported optional features:\n", devtoname(dev));
307			for (i = 0;
308			    i < sizeof(ro_compat)/sizeof(struct ext2_feature);
309			    i++)
310				if (mask & ro_compat[i].mask)
311					printf("%s ", ro_compat[i].name);
312			printf("\n");
313			return (1);
314		}
315	}
316	return (0);
317}
318
319/*
320 * This computes the fields of the m_ext2fs structure from the
321 * data in the ext2fs structure read in.
322 */
323static int
324compute_sb_data(struct vnode *devvp, struct ext2fs *es,
325    struct m_ext2fs *fs)
326{
327	int db_count, error;
328	int i;
329	int logic_sb_block = 1;	/* XXX for now */
330	struct buf *bp;
331	uint32_t e2fs_descpb;
332
333	fs->e2fs_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->e2fs_log_bsize;
334	fs->e2fs_bsize = 1U << fs->e2fs_bshift;
335	fs->e2fs_fsbtodb = es->e2fs_log_bsize + 1;
336	fs->e2fs_qbmask = fs->e2fs_bsize - 1;
337	fs->e2fs_fsize = EXT2_MIN_FRAG_SIZE << es->e2fs_log_fsize;
338	if (fs->e2fs_fsize)
339		fs->e2fs_fpb = fs->e2fs_bsize / fs->e2fs_fsize;
340	fs->e2fs_bpg = es->e2fs_bpg;
341	fs->e2fs_fpg = es->e2fs_fpg;
342	fs->e2fs_ipg = es->e2fs_ipg;
343	if (es->e2fs_rev == E2FS_REV0) {
344		fs->e2fs_isize = E2FS_REV0_INODE_SIZE;
345	} else {
346		fs->e2fs_isize = es->e2fs_inode_size;
347
348		/*
349		 * Simple sanity check for superblock inode size value.
350		 */
351		if (EXT2_INODE_SIZE(fs) < E2FS_REV0_INODE_SIZE ||
352		    EXT2_INODE_SIZE(fs) > fs->e2fs_bsize ||
353		    (fs->e2fs_isize & (fs->e2fs_isize - 1)) != 0) {
354			printf("ext2fs: invalid inode size %d\n",
355			    fs->e2fs_isize);
356			return (EIO);
357		}
358	}
359	/* Check for extra isize in big inodes. */
360	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_EXTRA_ISIZE) &&
361	    EXT2_INODE_SIZE(fs) < sizeof(struct ext2fs_dinode)) {
362		printf("ext2fs: no space for extra inode timestamps\n");
363		return (EINVAL);
364	}
365	/* Check for group descriptor size */
366	if (EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_64BIT) &&
367	    (es->e3fs_desc_size != sizeof(struct ext2_gd))) {
368		printf("ext2fs: group descriptor size unsupported %d\n",
369		    es->e3fs_desc_size);
370		return (EINVAL);
371	}
372	/* Check for block size = 1K|2K|4K */
373	if (es->e2fs_log_bsize > 2) {
374		printf("ext2fs: bad block size: %d\n", es->e2fs_log_bsize);
375		return (EINVAL);
376	}
377	/* Check for group size */
378	if (fs->e2fs_bpg == 0 || fs->e2fs_fpg == 0) {
379		printf("ext2fs: zero blocks/fragments per group");
380		return (EINVAL);
381	} else if (fs->e2fs_bpg != fs->e2fs_fpg) {
382		printf("ext2fs: blocks per group not equal fragments per group");
383		return (EINVAL);
384	}
385	if (fs->e2fs_bpg != fs->e2fs_bsize * 8) {
386		printf("ext2fs: non-standard group size unsupported %d\n",
387		    fs->e2fs_bpg);
388		return (EINVAL);
389	}
390
391	fs->e2fs_ipb = fs->e2fs_bsize / EXT2_INODE_SIZE(fs);
392	if (fs->e2fs_ipg == 0) {
393		printf("ext2fs: zero inodes per group\n");
394		return (EINVAL);
395	}
396	fs->e2fs_itpg = fs->e2fs_ipg / fs->e2fs_ipb;
397	/* s_resuid / s_resgid ? */
398	fs->e2fs_gcount = howmany(es->e2fs_bcount - es->e2fs_first_dblock,
399	    EXT2_BLOCKS_PER_GROUP(fs));
400	e2fs_descpb = fs->e2fs_bsize / sizeof(struct ext2_gd);
401	db_count = howmany(fs->e2fs_gcount, e2fs_descpb);
402	fs->e2fs_gdbcount = db_count;
403	fs->e2fs_gd = malloc(db_count * fs->e2fs_bsize,
404	    M_EXT2MNT, M_WAITOK);
405	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount *
406	    sizeof(*fs->e2fs_contigdirs), M_EXT2MNT, M_WAITOK | M_ZERO);
407
408	/*
409	 * Adjust logic_sb_block.
410	 * Godmar thinks: if the blocksize is greater than 1024, then
411	 * the superblock is logically part of block zero.
412	 */
413	if (fs->e2fs_bsize > SBSIZE)
414		logic_sb_block = 0;
415	for (i = 0; i < db_count; i++) {
416		error = bread(devvp,
417		    fsbtodb(fs, logic_sb_block + i + 1),
418		    fs->e2fs_bsize, NOCRED, &bp);
419		if (error) {
420			free(fs->e2fs_contigdirs, M_EXT2MNT);
421			free(fs->e2fs_gd, M_EXT2MNT);
422			brelse(bp);
423			return (error);
424		}
425		e2fs_cgload((struct ext2_gd *)bp->b_data,
426		    &fs->e2fs_gd[
427		    i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
428		    fs->e2fs_bsize);
429		brelse(bp);
430		bp = NULL;
431	}
432	/* Verify cg csum */
433	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) {
434		error = ext2_gd_csum_verify(fs, devvp->v_rdev);
435		if (error)
436			return (error);
437	}
438	/* Initialization for the ext2 Orlov allocator variant. */
439	fs->e2fs_total_dir = 0;
440	for (i = 0; i < fs->e2fs_gcount; i++)
441		fs->e2fs_total_dir += fs->e2fs_gd[i].ext2bgd_ndirs;
442
443	if (es->e2fs_rev == E2FS_REV0 ||
444	    !EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_LARGEFILE))
445		fs->e2fs_maxfilesize = 0x7fffffff;
446	else {
447		fs->e2fs_maxfilesize = 0xffffffffffff;
448		if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_HUGE_FILE))
449			fs->e2fs_maxfilesize = 0x7fffffffffffffff;
450	}
451	if (es->e4fs_flags & E2FS_UNSIGNED_HASH) {
452		fs->e2fs_uhash = 3;
453	} else if ((es->e4fs_flags & E2FS_SIGNED_HASH) == 0) {
454#ifdef __CHAR_UNSIGNED__
455		es->e4fs_flags |= E2FS_UNSIGNED_HASH;
456		fs->e2fs_uhash = 3;
457#else
458		es->e4fs_flags |= E2FS_SIGNED_HASH;
459#endif
460	}
461
462	return (0);
463}
464
465/*
466 * Reload all incore data for a filesystem (used after running fsck on
467 * the root filesystem and finding things to fix). The filesystem must
468 * be mounted read-only.
469 *
470 * Things to do to update the mount:
471 *	1) invalidate all cached meta-data.
472 *	2) re-read superblock from disk.
473 *	3) invalidate all cluster summary information.
474 *	4) invalidate all inactive vnodes.
475 *	5) invalidate all cached file data.
476 *	6) re-read inode data for all active vnodes.
477 * XXX we are missing some steps, in particular # 3, this has to be reviewed.
478 */
479static int
480ext2_reload(struct mount *mp, struct thread *td)
481{
482	struct vnode *vp, *mvp, *devvp;
483	struct inode *ip;
484	struct buf *bp;
485	struct ext2fs *es;
486	struct m_ext2fs *fs;
487	struct csum *sump;
488	int error, i;
489	int32_t *lp;
490
491	if ((mp->mnt_flag & MNT_RDONLY) == 0)
492		return (EINVAL);
493	/*
494	 * Step 1: invalidate all cached meta-data.
495	 */
496	devvp = VFSTOEXT2(mp)->um_devvp;
497	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
498	if (vinvalbuf(devvp, 0, 0, 0) != 0)
499		panic("ext2_reload: dirty1");
500	VOP_UNLOCK(devvp, 0);
501
502	/*
503	 * Step 2: re-read superblock from disk.
504	 * constants have been adjusted for ext2
505	 */
506	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
507		return (error);
508	es = (struct ext2fs *)bp->b_data;
509	if (ext2_check_sb_compat(es, devvp->v_rdev, 0) != 0) {
510		brelse(bp);
511		return (EIO);		/* XXX needs translation */
512	}
513	fs = VFSTOEXT2(mp)->um_e2fs;
514	bcopy(bp->b_data, fs->e2fs, sizeof(struct ext2fs));
515
516	if ((error = compute_sb_data(devvp, es, fs)) != 0) {
517		brelse(bp);
518		return (error);
519	}
520#ifdef UNKLAR
521	if (fs->fs_sbsize < SBSIZE)
522		bp->b_flags |= B_INVAL;
523#endif
524	brelse(bp);
525
526	/*
527	 * Step 3: invalidate all cluster summary information.
528	 */
529	if (fs->e2fs_contigsumsize > 0) {
530		lp = fs->e2fs_maxcluster;
531		sump = fs->e2fs_clustersum;
532		for (i = 0; i < fs->e2fs_gcount; i++, sump++) {
533			*lp++ = fs->e2fs_contigsumsize;
534			sump->cs_init = 0;
535			bzero(sump->cs_sum, fs->e2fs_contigsumsize + 1);
536		}
537	}
538
539loop:
540	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
541		/*
542		 * Step 4: invalidate all cached file data.
543		 */
544		if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
545			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
546			goto loop;
547		}
548		if (vinvalbuf(vp, 0, 0, 0))
549			panic("ext2_reload: dirty2");
550
551		/*
552		 * Step 5: re-read inode data for all active vnodes.
553		 */
554		ip = VTOI(vp);
555		error = bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
556		    (int)fs->e2fs_bsize, NOCRED, &bp);
557		if (error) {
558			VOP_UNLOCK(vp, 0);
559			vrele(vp);
560			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
561			return (error);
562		}
563		ext2_ei2i((struct ext2fs_dinode *)((char *)bp->b_data +
564		    EXT2_INODE_SIZE(fs) * ino_to_fsbo(fs, ip->i_number)), ip);
565		brelse(bp);
566		VOP_UNLOCK(vp, 0);
567		vrele(vp);
568	}
569	return (0);
570}
571
572/*
573 * Common code for mount and mountroot.
574 */
575static int
576ext2_mountfs(struct vnode *devvp, struct mount *mp)
577{
578	struct ext2mount *ump;
579	struct buf *bp;
580	struct m_ext2fs *fs;
581	struct ext2fs *es;
582	struct cdev *dev = devvp->v_rdev;
583	struct g_consumer *cp;
584	struct bufobj *bo;
585	struct csum *sump;
586	int error;
587	int ronly;
588	int i;
589	u_long size;
590	int32_t *lp;
591	int32_t e2fs_maxcontig;
592
593	ronly = vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0);
594	/* XXX: use VOP_ACESS to check FS perms */
595	g_topology_lock();
596	error = g_vfs_open(devvp, &cp, "ext2fs", ronly ? 0 : 1);
597	g_topology_unlock();
598	VOP_UNLOCK(devvp, 0);
599	if (error)
600		return (error);
601
602	/* XXX: should we check for some sectorsize or 512 instead? */
603	if (((SBSIZE % cp->provider->sectorsize) != 0) ||
604	    (SBSIZE < cp->provider->sectorsize)) {
605		g_topology_lock();
606		g_vfs_close(cp);
607		g_topology_unlock();
608		return (EINVAL);
609	}
610
611	bo = &devvp->v_bufobj;
612	bo->bo_private = cp;
613	bo->bo_ops = g_vfs_bufops;
614	if (devvp->v_rdev->si_iosize_max != 0)
615		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
616	if (mp->mnt_iosize_max > MAXPHYS)
617		mp->mnt_iosize_max = MAXPHYS;
618
619	bp = NULL;
620	ump = NULL;
621	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
622		goto out;
623	es = (struct ext2fs *)bp->b_data;
624	if (ext2_check_sb_compat(es, dev, ronly) != 0) {
625		error = EINVAL;		/* XXX needs translation */
626		goto out;
627	}
628	if ((es->e2fs_state & E2FS_ISCLEAN) == 0 ||
629	    (es->e2fs_state & E2FS_ERRORS)) {
630		if (ronly || (mp->mnt_flag & MNT_FORCE)) {
631			printf(
632"WARNING: Filesystem was not properly dismounted\n");
633		} else {
634			printf(
635"WARNING: R/W mount denied.  Filesystem is not clean - run fsck\n");
636			error = EPERM;
637			goto out;
638		}
639	}
640	ump = malloc(sizeof(*ump), M_EXT2MNT, M_WAITOK | M_ZERO);
641
642	/*
643	 * I don't know whether this is the right strategy. Note that
644	 * we dynamically allocate both an m_ext2fs and an ext2fs
645	 * while Linux keeps the super block in a locked buffer.
646	 */
647	ump->um_e2fs = malloc(sizeof(struct m_ext2fs),
648	    M_EXT2MNT, M_WAITOK | M_ZERO);
649	ump->um_e2fs->e2fs = malloc(sizeof(struct ext2fs),
650	    M_EXT2MNT, M_WAITOK);
651	mtx_init(EXT2_MTX(ump), "EXT2FS", "EXT2FS Lock", MTX_DEF);
652	bcopy(es, ump->um_e2fs->e2fs, (u_int)sizeof(struct ext2fs));
653	if ((error = compute_sb_data(devvp, ump->um_e2fs->e2fs, ump->um_e2fs)))
654		goto out;
655
656	/*
657	 * Calculate the maximum contiguous blocks and size of cluster summary
658	 * array.  In FFS this is done by newfs; however, the superblock
659	 * in ext2fs doesn't have these variables, so we can calculate
660	 * them here.
661	 */
662	e2fs_maxcontig = MAX(1, MAXPHYS / ump->um_e2fs->e2fs_bsize);
663	ump->um_e2fs->e2fs_contigsumsize = MIN(e2fs_maxcontig, EXT2_MAXCONTIG);
664	if (ump->um_e2fs->e2fs_contigsumsize > 0) {
665		size = ump->um_e2fs->e2fs_gcount * sizeof(int32_t);
666		ump->um_e2fs->e2fs_maxcluster = malloc(size, M_EXT2MNT, M_WAITOK);
667		size = ump->um_e2fs->e2fs_gcount * sizeof(struct csum);
668		ump->um_e2fs->e2fs_clustersum = malloc(size, M_EXT2MNT, M_WAITOK);
669		lp = ump->um_e2fs->e2fs_maxcluster;
670		sump = ump->um_e2fs->e2fs_clustersum;
671		for (i = 0; i < ump->um_e2fs->e2fs_gcount; i++, sump++) {
672			*lp++ = ump->um_e2fs->e2fs_contigsumsize;
673			sump->cs_init = 0;
674			sump->cs_sum = malloc((ump->um_e2fs->e2fs_contigsumsize + 1) *
675			    sizeof(int32_t), M_EXT2MNT, M_WAITOK | M_ZERO);
676		}
677	}
678
679	brelse(bp);
680	bp = NULL;
681	fs = ump->um_e2fs;
682	fs->e2fs_ronly = ronly;	/* ronly is set according to mnt_flags */
683
684	/*
685	 * If the fs is not mounted read-only, make sure the super block is
686	 * always written back on a sync().
687	 */
688	fs->e2fs_wasvalid = fs->e2fs->e2fs_state & E2FS_ISCLEAN ? 1 : 0;
689	if (ronly == 0) {
690		fs->e2fs_fmod = 1;	/* mark it modified */
691		fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;	/* set fs invalid */
692	}
693	mp->mnt_data = ump;
694	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
695	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
696	mp->mnt_maxsymlinklen = EXT2_MAXSYMLINKLEN;
697	MNT_ILOCK(mp);
698	mp->mnt_flag |= MNT_LOCAL;
699	MNT_IUNLOCK(mp);
700	ump->um_mountp = mp;
701	ump->um_dev = dev;
702	ump->um_devvp = devvp;
703	ump->um_bo = &devvp->v_bufobj;
704	ump->um_cp = cp;
705
706	/*
707	 * Setting those two parameters allowed us to use
708	 * ufs_bmap w/o changse!
709	 */
710	ump->um_nindir = EXT2_ADDR_PER_BLOCK(fs);
711	ump->um_bptrtodb = fs->e2fs->e2fs_log_bsize + 1;
712	ump->um_seqinc = EXT2_FRAGS_PER_BLOCK(fs);
713	if (ronly == 0)
714		ext2_sbupdate(ump, MNT_WAIT);
715	/*
716	 * Initialize filesystem stat information in mount struct.
717	 */
718	MNT_ILOCK(mp);
719	mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED |
720	    MNTK_USES_BCACHE;
721	MNT_IUNLOCK(mp);
722	return (0);
723out:
724	if (bp)
725		brelse(bp);
726	if (cp != NULL) {
727		g_topology_lock();
728		g_vfs_close(cp);
729		g_topology_unlock();
730	}
731	if (ump) {
732		mtx_destroy(EXT2_MTX(ump));
733		free(ump->um_e2fs->e2fs_gd, M_EXT2MNT);
734		free(ump->um_e2fs->e2fs_contigdirs, M_EXT2MNT);
735		free(ump->um_e2fs->e2fs, M_EXT2MNT);
736		free(ump->um_e2fs, M_EXT2MNT);
737		free(ump, M_EXT2MNT);
738		mp->mnt_data = NULL;
739	}
740	return (error);
741}
742
743/*
744 * Unmount system call.
745 */
746static int
747ext2_unmount(struct mount *mp, int mntflags)
748{
749	struct ext2mount *ump;
750	struct m_ext2fs *fs;
751	struct csum *sump;
752	int error, flags, i, ronly;
753
754	flags = 0;
755	if (mntflags & MNT_FORCE) {
756		if (mp->mnt_flag & MNT_ROOTFS)
757			return (EINVAL);
758		flags |= FORCECLOSE;
759	}
760	if ((error = ext2_flushfiles(mp, flags, curthread)) != 0)
761		return (error);
762	ump = VFSTOEXT2(mp);
763	fs = ump->um_e2fs;
764	ronly = fs->e2fs_ronly;
765	if (ronly == 0 && ext2_cgupdate(ump, MNT_WAIT) == 0) {
766		if (fs->e2fs_wasvalid)
767			fs->e2fs->e2fs_state |= E2FS_ISCLEAN;
768		ext2_sbupdate(ump, MNT_WAIT);
769	}
770
771	g_topology_lock();
772	g_vfs_close(ump->um_cp);
773	g_topology_unlock();
774	vrele(ump->um_devvp);
775	sump = fs->e2fs_clustersum;
776	for (i = 0; i < fs->e2fs_gcount; i++, sump++)
777		free(sump->cs_sum, M_EXT2MNT);
778	free(fs->e2fs_clustersum, M_EXT2MNT);
779	free(fs->e2fs_maxcluster, M_EXT2MNT);
780	free(fs->e2fs_gd, M_EXT2MNT);
781	free(fs->e2fs_contigdirs, M_EXT2MNT);
782	free(fs->e2fs, M_EXT2MNT);
783	free(fs, M_EXT2MNT);
784	free(ump, M_EXT2MNT);
785	mp->mnt_data = NULL;
786	MNT_ILOCK(mp);
787	mp->mnt_flag &= ~MNT_LOCAL;
788	MNT_IUNLOCK(mp);
789	return (error);
790}
791
792/*
793 * Flush out all the files in a filesystem.
794 */
795static int
796ext2_flushfiles(struct mount *mp, int flags, struct thread *td)
797{
798	int error;
799
800	error = vflush(mp, 0, flags, td);
801	return (error);
802}
803
804/*
805 * Get filesystem statistics.
806 */
807int
808ext2_statfs(struct mount *mp, struct statfs *sbp)
809{
810	struct ext2mount *ump;
811	struct m_ext2fs *fs;
812	uint32_t overhead, overhead_per_group, ngdb;
813	int i, ngroups;
814
815	ump = VFSTOEXT2(mp);
816	fs = ump->um_e2fs;
817	if (fs->e2fs->e2fs_magic != E2FS_MAGIC)
818		panic("ext2_statfs");
819
820	/*
821	 * Compute the overhead (FS structures)
822	 */
823	overhead_per_group =
824	    1 /* block bitmap */ +
825	    1 /* inode bitmap */ +
826	    fs->e2fs_itpg;
827	overhead = fs->e2fs->e2fs_first_dblock +
828	    fs->e2fs_gcount * overhead_per_group;
829	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
830	    fs->e2fs->e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) {
831		for (i = 0, ngroups = 0; i < fs->e2fs_gcount; i++) {
832			if (ext2_cg_has_sb(fs, i))
833				ngroups++;
834		}
835	} else {
836		ngroups = fs->e2fs_gcount;
837	}
838	ngdb = fs->e2fs_gdbcount;
839	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
840	    fs->e2fs->e2fs_features_compat & EXT2F_COMPAT_RESIZE)
841		ngdb += fs->e2fs->e2fs_reserved_ngdb;
842	overhead += ngroups * (1 /* superblock */ + ngdb);
843
844	sbp->f_bsize = EXT2_FRAG_SIZE(fs);
845	sbp->f_iosize = EXT2_BLOCK_SIZE(fs);
846	sbp->f_blocks = fs->e2fs->e2fs_bcount - overhead;
847	sbp->f_bfree = fs->e2fs->e2fs_fbcount;
848	sbp->f_bavail = sbp->f_bfree - fs->e2fs->e2fs_rbcount;
849	sbp->f_files = fs->e2fs->e2fs_icount;
850	sbp->f_ffree = fs->e2fs->e2fs_ficount;
851	return (0);
852}
853
854/*
855 * Go through the disk queues to initiate sandbagged IO;
856 * go through the inodes to write those that have been modified;
857 * initiate the writing of the super block if it has been modified.
858 *
859 * Note: we are always called with the filesystem marked `MPBUSY'.
860 */
861static int
862ext2_sync(struct mount *mp, int waitfor)
863{
864	struct vnode *mvp, *vp;
865	struct thread *td;
866	struct inode *ip;
867	struct ext2mount *ump = VFSTOEXT2(mp);
868	struct m_ext2fs *fs;
869	int error, allerror = 0;
870
871	td = curthread;
872	fs = ump->um_e2fs;
873	if (fs->e2fs_fmod != 0 && fs->e2fs_ronly != 0) {		/* XXX */
874		printf("fs = %s\n", fs->e2fs_fsmnt);
875		panic("ext2_sync: rofs mod");
876	}
877
878	/*
879	 * Write back each (modified) inode.
880	 */
881loop:
882	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
883		if (vp->v_type == VNON) {
884			VI_UNLOCK(vp);
885			continue;
886		}
887		ip = VTOI(vp);
888		if ((ip->i_flag &
889		    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
890		    (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
891		    waitfor == MNT_LAZY)) {
892			VI_UNLOCK(vp);
893			continue;
894		}
895		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
896		if (error) {
897			if (error == ENOENT) {
898				MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
899				goto loop;
900			}
901			continue;
902		}
903		if ((error = VOP_FSYNC(vp, waitfor, td)) != 0)
904			allerror = error;
905		VOP_UNLOCK(vp, 0);
906		vrele(vp);
907	}
908
909	/*
910	 * Force stale filesystem control information to be flushed.
911	 */
912	if (waitfor != MNT_LAZY) {
913		vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
914		if ((error = VOP_FSYNC(ump->um_devvp, waitfor, td)) != 0)
915			allerror = error;
916		VOP_UNLOCK(ump->um_devvp, 0);
917	}
918
919	/*
920	 * Write back modified superblock.
921	 */
922	if (fs->e2fs_fmod != 0) {
923		fs->e2fs_fmod = 0;
924		fs->e2fs->e2fs_wtime = time_second;
925		if ((error = ext2_cgupdate(ump, waitfor)) != 0)
926			allerror = error;
927	}
928	return (allerror);
929}
930
931/*
932 * Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
933 * in from disk.  If it is in core, wait for the lock bit to clear, then
934 * return the inode locked.  Detection and handling of mount points must be
935 * done by the calling routine.
936 */
937static int
938ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
939{
940	struct m_ext2fs *fs;
941	struct inode *ip;
942	struct ext2mount *ump;
943	struct buf *bp;
944	struct vnode *vp;
945	struct thread *td;
946	unsigned int i, used_blocks;
947	int error;
948
949	td = curthread;
950	error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
951	if (error || *vpp != NULL)
952		return (error);
953
954	ump = VFSTOEXT2(mp);
955	ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
956
957	/* Allocate a new vnode/inode. */
958	if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
959		*vpp = NULL;
960		free(ip, M_EXT2NODE);
961		return (error);
962	}
963	vp->v_data = ip;
964	ip->i_vnode = vp;
965	ip->i_e2fs = fs = ump->um_e2fs;
966	ip->i_ump = ump;
967	ip->i_number = ino;
968
969	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
970	error = insmntque(vp, mp);
971	if (error != 0) {
972		free(ip, M_EXT2NODE);
973		*vpp = NULL;
974		return (error);
975	}
976	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
977	if (error || *vpp != NULL)
978		return (error);
979
980	/* Read in the disk contents for the inode, copy into the inode. */
981	if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
982	    (int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
983		/*
984		 * The inode does not contain anything useful, so it would
985		 * be misleading to leave it on its hash chain. With mode
986		 * still zero, it will be unlinked and returned to the free
987		 * list by vput().
988		 */
989		brelse(bp);
990		vput(vp);
991		*vpp = NULL;
992		return (error);
993	}
994	/* convert ext2 inode to dinode */
995	ext2_ei2i((struct ext2fs_dinode *)((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
996	    ino_to_fsbo(fs, ino)), ip);
997	ip->i_block_group = ino_to_cg(fs, ino);
998	ip->i_next_alloc_block = 0;
999	ip->i_next_alloc_goal = 0;
1000
1001	/*
1002	 * Now we want to make sure that block pointers for unused
1003	 * blocks are zeroed out - ext2_balloc depends on this
1004	 * although for regular files and directories only
1005	 *
1006	 * If IN_E4EXTENTS is enabled, unused blocks are not zeroed
1007	 * out because we could corrupt the extent tree.
1008	 */
1009	if (!(ip->i_flag & IN_E4EXTENTS) &&
1010	    (S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode))) {
1011		used_blocks = howmany(ip->i_size, fs->e2fs_bsize);
1012		for (i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
1013			ip->i_db[i] = 0;
1014	}
1015#ifdef EXT2FS_DEBUG
1016	ext2_print_inode(ip);
1017#endif
1018	bqrelse(bp);
1019
1020	/*
1021	 * Initialize the vnode from the inode, check for aliases.
1022	 * Note that the underlying vnode may have changed.
1023	 */
1024	if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
1025		vput(vp);
1026		*vpp = NULL;
1027		return (error);
1028	}
1029
1030	/*
1031	 * Finish inode initialization.
1032	 */
1033
1034	*vpp = vp;
1035	return (0);
1036}
1037
1038/*
1039 * File handle to vnode
1040 *
1041 * Have to be really careful about stale file handles:
1042 * - check that the inode number is valid
1043 * - call ext2_vget() to get the locked inode
1044 * - check for an unallocated inode (i_mode == 0)
1045 * - check that the given client host has export rights and return
1046 *   those rights via. exflagsp and credanonp
1047 */
1048static int
1049ext2_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
1050{
1051	struct inode *ip;
1052	struct ufid *ufhp;
1053	struct vnode *nvp;
1054	struct m_ext2fs *fs;
1055	int error;
1056
1057	ufhp = (struct ufid *)fhp;
1058	fs = VFSTOEXT2(mp)->um_e2fs;
1059	if (ufhp->ufid_ino < EXT2_ROOTINO ||
1060	    ufhp->ufid_ino > fs->e2fs_gcount * fs->e2fs->e2fs_ipg)
1061		return (ESTALE);
1062
1063	error = VFS_VGET(mp, ufhp->ufid_ino, LK_EXCLUSIVE, &nvp);
1064	if (error) {
1065		*vpp = NULLVP;
1066		return (error);
1067	}
1068	ip = VTOI(nvp);
1069	if (ip->i_mode == 0 ||
1070	    ip->i_gen != ufhp->ufid_gen || ip->i_nlink <= 0) {
1071		vput(nvp);
1072		*vpp = NULLVP;
1073		return (ESTALE);
1074	}
1075	*vpp = nvp;
1076	vnode_create_vobject(*vpp, 0, curthread);
1077	return (0);
1078}
1079
1080/*
1081 * Write a superblock and associated information back to disk.
1082 */
1083static int
1084ext2_sbupdate(struct ext2mount *mp, int waitfor)
1085{
1086	struct m_ext2fs *fs = mp->um_e2fs;
1087	struct ext2fs *es = fs->e2fs;
1088	struct buf *bp;
1089	int error = 0;
1090
1091	bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0, 0);
1092	bcopy((caddr_t)es, bp->b_data, (u_int)sizeof(struct ext2fs));
1093	if (waitfor == MNT_WAIT)
1094		error = bwrite(bp);
1095	else
1096		bawrite(bp);
1097
1098	/*
1099	 * The buffers for group descriptors, inode bitmaps and block bitmaps
1100	 * are not busy at this point and are (hopefully) written by the
1101	 * usual sync mechanism. No need to write them here.
1102	 */
1103	return (error);
1104}
1105int
1106ext2_cgupdate(struct ext2mount *mp, int waitfor)
1107{
1108	struct m_ext2fs *fs = mp->um_e2fs;
1109	struct buf *bp;
1110	int i, error = 0, allerror = 0;
1111
1112	allerror = ext2_sbupdate(mp, waitfor);
1113
1114	/* Update gd csums */
1115	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM))
1116		ext2_gd_csum_set(fs);
1117
1118	for (i = 0; i < fs->e2fs_gdbcount; i++) {
1119		bp = getblk(mp->um_devvp, fsbtodb(fs,
1120		    fs->e2fs->e2fs_first_dblock +
1121		    1 /* superblock */ + i), fs->e2fs_bsize, 0, 0, 0);
1122		e2fs_cgsave(&fs->e2fs_gd[
1123		    i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
1124		    (struct ext2_gd *)bp->b_data, fs->e2fs_bsize);
1125		if (waitfor == MNT_WAIT)
1126			error = bwrite(bp);
1127		else
1128			bawrite(bp);
1129	}
1130
1131	if (!allerror && error)
1132		allerror = error;
1133	return (allerror);
1134}
1135
1136/*
1137 * Return the root of a filesystem.
1138 */
1139static int
1140ext2_root(struct mount *mp, int flags, struct vnode **vpp)
1141{
1142	struct vnode *nvp;
1143	int error;
1144
1145	error = VFS_VGET(mp, EXT2_ROOTINO, LK_EXCLUSIVE, &nvp);
1146	if (error)
1147		return (error);
1148	*vpp = nvp;
1149	return (0);
1150}
1151