ext2_vfsops.c revision 281841
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/10/sys/fs/ext2fs/ext2_vfsops.c 281841 2015-04-22 00:38:11Z pfg $
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			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
283static int
284ext2_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						   EXT4F_RO_INCOMPAT_SUPP)) {
295			printf(
296"WARNING: mount of %s denied due to unsupported optional features\n",
297			    devtoname(dev));
298			return (1);
299		}
300		if (!ronly &&
301		    (es->e2fs_features_rocompat & ~EXT2F_ROCOMPAT_SUPP)) {
302			printf("WARNING: R/W mount of %s denied due to "
303			    "unsupported optional features\n", devtoname(dev));
304			return (1);
305		}
306	}
307	return (0);
308}
309
310/*
311 * This computes the fields of the  ext2_sb_info structure from the
312 * data in the ext2_super_block structure read in.
313 */
314static int
315compute_sb_data(struct vnode *devvp, struct ext2fs *es,
316    struct m_ext2fs *fs)
317{
318	int db_count, error;
319	int i;
320	int logic_sb_block = 1;	/* XXX for now */
321	struct buf *bp;
322	uint32_t e2fs_descpb;
323
324	fs->e2fs_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->e2fs_log_bsize;
325	fs->e2fs_bsize = 1U << fs->e2fs_bshift;
326	fs->e2fs_fsbtodb = es->e2fs_log_bsize + 1;
327	fs->e2fs_qbmask = fs->e2fs_bsize - 1;
328	fs->e2fs_fsize = EXT2_MIN_FRAG_SIZE << es->e2fs_log_fsize;
329	if (fs->e2fs_fsize)
330		fs->e2fs_fpb = fs->e2fs_bsize / fs->e2fs_fsize;
331	fs->e2fs_bpg = es->e2fs_bpg;
332	fs->e2fs_fpg = es->e2fs_fpg;
333	fs->e2fs_ipg = es->e2fs_ipg;
334	if (es->e2fs_rev == E2FS_REV0) {
335		fs->e2fs_isize = E2FS_REV0_INODE_SIZE ;
336	} else {
337		fs->e2fs_isize = es->e2fs_inode_size;
338
339		/*
340		 * Simple sanity check for superblock inode size value.
341		 */
342		if (EXT2_INODE_SIZE(fs) < E2FS_REV0_INODE_SIZE ||
343		    EXT2_INODE_SIZE(fs) > fs->e2fs_bsize ||
344		    (fs->e2fs_isize & (fs->e2fs_isize - 1)) != 0) {
345			printf("ext2fs: invalid inode size %d\n",
346			    fs->e2fs_isize);
347			return (EIO);
348		}
349	}
350	/* Check for extra isize in big inodes. */
351	if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_EXTRA_ISIZE) &&
352	    EXT2_INODE_SIZE(fs) < sizeof(struct ext2fs_dinode)) {
353		printf("ext2fs: no space for extra inode timestamps\n");
354		return (EINVAL);
355	}
356
357	fs->e2fs_ipb = fs->e2fs_bsize / EXT2_INODE_SIZE(fs);
358	fs->e2fs_itpg = fs->e2fs_ipg / fs->e2fs_ipb;
359	/* s_resuid / s_resgid ? */
360	fs->e2fs_gcount = (es->e2fs_bcount - es->e2fs_first_dblock +
361	    EXT2_BLOCKS_PER_GROUP(fs) - 1) / EXT2_BLOCKS_PER_GROUP(fs);
362	e2fs_descpb = fs->e2fs_bsize / sizeof(struct ext2_gd);
363	db_count = (fs->e2fs_gcount + e2fs_descpb - 1) / e2fs_descpb;
364	fs->e2fs_gdbcount = db_count;
365	fs->e2fs_gd = malloc(db_count * fs->e2fs_bsize,
366	    M_EXT2MNT, M_WAITOK);
367	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount *
368	    sizeof(*fs->e2fs_contigdirs), M_EXT2MNT, M_WAITOK | M_ZERO);
369
370	/*
371	 * Adjust logic_sb_block.
372	 * Godmar thinks: if the blocksize is greater than 1024, then
373	 * the superblock is logically part of block zero.
374	 */
375	if(fs->e2fs_bsize > SBSIZE)
376		logic_sb_block = 0;
377	for (i = 0; i < db_count; i++) {
378		error = bread(devvp ,
379			 fsbtodb(fs, logic_sb_block + i + 1 ),
380			fs->e2fs_bsize, NOCRED, &bp);
381		if (error) {
382			free(fs->e2fs_contigdirs, M_EXT2MNT);
383			free(fs->e2fs_gd, M_EXT2MNT);
384			brelse(bp);
385			return (error);
386		}
387		e2fs_cgload((struct ext2_gd *)bp->b_data,
388		    &fs->e2fs_gd[
389			i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
390		    fs->e2fs_bsize);
391		brelse(bp);
392		bp = NULL;
393	}
394	/* Initialization for the ext2 Orlov allocator variant. */
395	fs->e2fs_total_dir = 0;
396	for (i = 0; i < fs->e2fs_gcount; i++)
397		fs->e2fs_total_dir += fs->e2fs_gd[i].ext2bgd_ndirs;
398
399	if (es->e2fs_rev == E2FS_REV0 ||
400	    !EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_LARGEFILE))
401		fs->e2fs_maxfilesize = 0x7fffffff;
402	else
403		fs->e2fs_maxfilesize = 0x7fffffffffffffff;
404	return (0);
405}
406
407/*
408 * Reload all incore data for a filesystem (used after running fsck on
409 * the root filesystem and finding things to fix). The filesystem must
410 * be mounted read-only.
411 *
412 * Things to do to update the mount:
413 *	1) invalidate all cached meta-data.
414 *	2) re-read superblock from disk.
415 *	3) invalidate all cluster summary information.
416 *	4) invalidate all inactive vnodes.
417 *	5) invalidate all cached file data.
418 *	6) re-read inode data for all active vnodes.
419 * XXX we are missing some steps, in particular # 3, this has to be reviewed.
420 */
421static int
422ext2_reload(struct mount *mp, struct thread *td)
423{
424	struct vnode *vp, *mvp, *devvp;
425	struct inode *ip;
426	struct buf *bp;
427	struct ext2fs *es;
428	struct m_ext2fs *fs;
429	struct csum *sump;
430	int error, i;
431	int32_t *lp;
432
433	if ((mp->mnt_flag & MNT_RDONLY) == 0)
434		return (EINVAL);
435	/*
436	 * Step 1: invalidate all cached meta-data.
437	 */
438	devvp = VFSTOEXT2(mp)->um_devvp;
439	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
440	if (vinvalbuf(devvp, 0, 0, 0) != 0)
441		panic("ext2_reload: dirty1");
442	VOP_UNLOCK(devvp, 0);
443
444	/*
445	 * Step 2: re-read superblock from disk.
446	 * constants have been adjusted for ext2
447	 */
448	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
449		return (error);
450	es = (struct ext2fs *)bp->b_data;
451	if (ext2_check_sb_compat(es, devvp->v_rdev, 0) != 0) {
452		brelse(bp);
453		return (EIO);		/* XXX needs translation */
454	}
455	fs = VFSTOEXT2(mp)->um_e2fs;
456	bcopy(bp->b_data, fs->e2fs, sizeof(struct ext2fs));
457
458	if((error = compute_sb_data(devvp, es, fs)) != 0) {
459		brelse(bp);
460		return (error);
461	}
462#ifdef UNKLAR
463	if (fs->fs_sbsize < SBSIZE)
464		bp->b_flags |= B_INVAL;
465#endif
466	brelse(bp);
467
468	/*
469	 * Step 3: invalidate all cluster summary information.
470	 */
471	if (fs->e2fs_contigsumsize > 0) {
472		lp = fs->e2fs_maxcluster;
473		sump = fs->e2fs_clustersum;
474		for (i = 0; i < fs->e2fs_gcount; i++, sump++) {
475			*lp++ = fs->e2fs_contigsumsize;
476			sump->cs_init = 0;
477			bzero(sump->cs_sum, fs->e2fs_contigsumsize + 1);
478		}
479	}
480
481loop:
482	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
483		/*
484		 * Step 4: invalidate all cached file data.
485		 */
486		if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
487			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
488			goto loop;
489		}
490		if (vinvalbuf(vp, 0, 0, 0))
491			panic("ext2_reload: dirty2");
492
493		/*
494		 * Step 5: re-read inode data for all active vnodes.
495		 */
496		ip = VTOI(vp);
497		error = bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
498		    (int)fs->e2fs_bsize, NOCRED, &bp);
499		if (error) {
500			VOP_UNLOCK(vp, 0);
501			vrele(vp);
502			MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
503			return (error);
504		}
505		ext2_ei2i((struct ext2fs_dinode *) ((char *)bp->b_data +
506		    EXT2_INODE_SIZE(fs) * ino_to_fsbo(fs, ip->i_number)), ip);
507		brelse(bp);
508		VOP_UNLOCK(vp, 0);
509		vrele(vp);
510	}
511	return (0);
512}
513
514/*
515 * Common code for mount and mountroot.
516 */
517static int
518ext2_mountfs(struct vnode *devvp, struct mount *mp)
519{
520	struct ext2mount *ump;
521	struct buf *bp;
522	struct m_ext2fs *fs;
523	struct ext2fs *es;
524	struct cdev *dev = devvp->v_rdev;
525	struct g_consumer *cp;
526	struct bufobj *bo;
527	struct csum *sump;
528	int error;
529	int ronly;
530	int i, size;
531	int32_t *lp;
532	int32_t e2fs_maxcontig;
533
534	ronly = vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0);
535	/* XXX: use VOP_ACESS to check FS perms */
536	DROP_GIANT();
537	g_topology_lock();
538	error = g_vfs_open(devvp, &cp, "ext2fs", ronly ? 0 : 1);
539	g_topology_unlock();
540	PICKUP_GIANT();
541	VOP_UNLOCK(devvp, 0);
542	if (error)
543		return (error);
544
545	/* XXX: should we check for some sectorsize or 512 instead? */
546	if (((SBSIZE % cp->provider->sectorsize) != 0) ||
547	    (SBSIZE < cp->provider->sectorsize)) {
548		DROP_GIANT();
549		g_topology_lock();
550		g_vfs_close(cp);
551		g_topology_unlock();
552		PICKUP_GIANT();
553		return (EINVAL);
554	}
555
556	bo = &devvp->v_bufobj;
557	bo->bo_private = cp;
558	bo->bo_ops = g_vfs_bufops;
559	if (devvp->v_rdev->si_iosize_max != 0)
560		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
561	if (mp->mnt_iosize_max > MAXPHYS)
562		mp->mnt_iosize_max = MAXPHYS;
563
564	bp = NULL;
565	ump = NULL;
566	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
567		goto out;
568	es = (struct ext2fs *)bp->b_data;
569	if (ext2_check_sb_compat(es, dev, ronly) != 0) {
570		error = EINVAL;		/* XXX needs translation */
571		goto out;
572	}
573	if ((es->e2fs_state & E2FS_ISCLEAN) == 0 ||
574	    (es->e2fs_state & E2FS_ERRORS)) {
575		if (ronly || (mp->mnt_flag & MNT_FORCE)) {
576			printf(
577"WARNING: Filesystem was not properly dismounted\n");
578		} else {
579			printf(
580"WARNING: R/W mount denied.  Filesystem is not clean - run fsck\n");
581			error = EPERM;
582			goto out;
583		}
584	}
585	ump = malloc(sizeof(*ump), M_EXT2MNT, M_WAITOK | M_ZERO);
586
587	/*
588	 * I don't know whether this is the right strategy. Note that
589	 * we dynamically allocate both an ext2_sb_info and an ext2_super_block
590	 * while Linux keeps the super block in a locked buffer.
591	 */
592	ump->um_e2fs = malloc(sizeof(struct m_ext2fs),
593		M_EXT2MNT, M_WAITOK);
594	ump->um_e2fs->e2fs = malloc(sizeof(struct ext2fs),
595		M_EXT2MNT, M_WAITOK);
596	mtx_init(EXT2_MTX(ump), "EXT2FS", "EXT2FS Lock", MTX_DEF);
597	bcopy(es, ump->um_e2fs->e2fs, (u_int)sizeof(struct ext2fs));
598	if ((error = compute_sb_data(devvp, ump->um_e2fs->e2fs, ump->um_e2fs)))
599		goto out;
600
601	/*
602	 * Calculate the maximum contiguous blocks and size of cluster summary
603	 * array.  In FFS this is done by newfs; however, the superblock
604	 * in ext2fs doesn't have these variables, so we can calculate
605	 * them here.
606	 */
607	e2fs_maxcontig = MAX(1, MAXPHYS / ump->um_e2fs->e2fs_bsize);
608	ump->um_e2fs->e2fs_contigsumsize = MIN(e2fs_maxcontig, EXT2_MAXCONTIG);
609	if (ump->um_e2fs->e2fs_contigsumsize > 0) {
610		size = ump->um_e2fs->e2fs_gcount * sizeof(int32_t);
611		ump->um_e2fs->e2fs_maxcluster = malloc(size, M_EXT2MNT, M_WAITOK);
612		size = ump->um_e2fs->e2fs_gcount * sizeof(struct csum);
613		ump->um_e2fs->e2fs_clustersum = malloc(size, M_EXT2MNT, M_WAITOK);
614		lp = ump->um_e2fs->e2fs_maxcluster;
615		sump = ump->um_e2fs->e2fs_clustersum;
616		for (i = 0; i < ump->um_e2fs->e2fs_gcount; i++, sump++) {
617			*lp++ = ump->um_e2fs->e2fs_contigsumsize;
618			sump->cs_init = 0;
619			sump->cs_sum = malloc((ump->um_e2fs->e2fs_contigsumsize + 1) *
620			    sizeof(int32_t), M_EXT2MNT, M_WAITOK | M_ZERO);
621		}
622	}
623
624	brelse(bp);
625	bp = NULL;
626	fs = ump->um_e2fs;
627	fs->e2fs_ronly = ronly;	/* ronly is set according to mnt_flags */
628
629	/*
630	 * If the fs is not mounted read-only, make sure the super block is
631	 * always written back on a sync().
632	 */
633	fs->e2fs_wasvalid = fs->e2fs->e2fs_state & E2FS_ISCLEAN ? 1 : 0;
634	if (ronly == 0) {
635		fs->e2fs_fmod = 1;		/* mark it modified */
636		fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;	/* set fs invalid */
637	}
638	mp->mnt_data = ump;
639	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
640	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
641	mp->mnt_maxsymlinklen = EXT2_MAXSYMLINKLEN;
642	MNT_ILOCK(mp);
643	mp->mnt_flag |= MNT_LOCAL;
644	MNT_IUNLOCK(mp);
645	ump->um_mountp = mp;
646	ump->um_dev = dev;
647	ump->um_devvp = devvp;
648	ump->um_bo = &devvp->v_bufobj;
649	ump->um_cp = cp;
650
651	/*
652	 * Setting those two parameters allowed us to use
653	 * ufs_bmap w/o changse!
654	 */
655	ump->um_nindir = EXT2_ADDR_PER_BLOCK(fs);
656	ump->um_bptrtodb = fs->e2fs->e2fs_log_bsize + 1;
657	ump->um_seqinc = EXT2_FRAGS_PER_BLOCK(fs);
658	if (ronly == 0)
659		ext2_sbupdate(ump, MNT_WAIT);
660	/*
661	 * Initialize filesystem stat information in mount struct.
662	 */
663	MNT_ILOCK(mp);
664	mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED;
665	MNT_IUNLOCK(mp);
666	return (0);
667out:
668	if (bp)
669		brelse(bp);
670	if (cp != NULL) {
671		DROP_GIANT();
672		g_topology_lock();
673		g_vfs_close(cp);
674		g_topology_unlock();
675		PICKUP_GIANT();
676	}
677	if (ump) {
678		mtx_destroy(EXT2_MTX(ump));
679		free(ump->um_e2fs->e2fs_gd, M_EXT2MNT);
680		free(ump->um_e2fs->e2fs_contigdirs, M_EXT2MNT);
681		free(ump->um_e2fs->e2fs, M_EXT2MNT);
682		free(ump->um_e2fs, M_EXT2MNT);
683		free(ump, M_EXT2MNT);
684		mp->mnt_data = NULL;
685	}
686	return (error);
687}
688
689/*
690 * Unmount system call.
691 */
692static int
693ext2_unmount(struct mount *mp, int mntflags)
694{
695	struct ext2mount *ump;
696	struct m_ext2fs *fs;
697	struct csum *sump;
698	int error, flags, i, ronly;
699
700	flags = 0;
701	if (mntflags & MNT_FORCE) {
702		if (mp->mnt_flag & MNT_ROOTFS)
703			return (EINVAL);
704		flags |= FORCECLOSE;
705	}
706	if ((error = ext2_flushfiles(mp, flags, curthread)) != 0)
707		return (error);
708	ump = VFSTOEXT2(mp);
709	fs = ump->um_e2fs;
710	ronly = fs->e2fs_ronly;
711	if (ronly == 0 && ext2_cgupdate(ump, MNT_WAIT) == 0) {
712		if (fs->e2fs_wasvalid)
713			fs->e2fs->e2fs_state |= E2FS_ISCLEAN;
714		ext2_sbupdate(ump, MNT_WAIT);
715	}
716
717	DROP_GIANT();
718	g_topology_lock();
719	g_vfs_close(ump->um_cp);
720	g_topology_unlock();
721	PICKUP_GIANT();
722	vrele(ump->um_devvp);
723	sump = fs->e2fs_clustersum;
724	for (i = 0; i < fs->e2fs_gcount; i++, sump++)
725		free(sump->cs_sum, M_EXT2MNT);
726	free(fs->e2fs_clustersum, M_EXT2MNT);
727	free(fs->e2fs_maxcluster, M_EXT2MNT);
728	free(fs->e2fs_gd, M_EXT2MNT);
729	free(fs->e2fs_contigdirs, M_EXT2MNT);
730	free(fs->e2fs, M_EXT2MNT);
731	free(fs, M_EXT2MNT);
732	free(ump, M_EXT2MNT);
733	mp->mnt_data = NULL;
734	MNT_ILOCK(mp);
735	mp->mnt_flag &= ~MNT_LOCAL;
736	MNT_IUNLOCK(mp);
737	return (error);
738}
739
740/*
741 * Flush out all the files in a filesystem.
742 */
743static int
744ext2_flushfiles(struct mount *mp, int flags, struct thread *td)
745{
746	int error;
747
748	error = vflush(mp, 0, flags, td);
749	return (error);
750}
751/*
752 * Get filesystem statistics.
753 */
754int
755ext2_statfs(struct mount *mp, struct statfs *sbp)
756{
757	struct ext2mount *ump;
758	struct m_ext2fs *fs;
759	uint32_t overhead, overhead_per_group, ngdb;
760	int i, ngroups;
761
762	ump = VFSTOEXT2(mp);
763	fs = ump->um_e2fs;
764	if (fs->e2fs->e2fs_magic != E2FS_MAGIC)
765		panic("ext2_statfs");
766
767	/*
768	 * Compute the overhead (FS structures)
769	 */
770	overhead_per_group =
771	    1 /* block bitmap */ +
772	    1 /* inode bitmap */ +
773	    fs->e2fs_itpg;
774	overhead = fs->e2fs->e2fs_first_dblock +
775	    fs->e2fs_gcount * overhead_per_group;
776	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
777	    fs->e2fs->e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) {
778		for (i = 0, ngroups = 0; i < fs->e2fs_gcount; i++) {
779			if (cg_has_sb(i))
780				ngroups++;
781		}
782	} else {
783		ngroups = fs->e2fs_gcount;
784	}
785	ngdb = fs->e2fs_gdbcount;
786	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
787	    fs->e2fs->e2fs_features_compat & EXT2F_COMPAT_RESIZE)
788		ngdb += fs->e2fs->e2fs_reserved_ngdb;
789	overhead += ngroups * (1 /* superblock */ + ngdb);
790
791	sbp->f_bsize = EXT2_FRAG_SIZE(fs);
792	sbp->f_iosize = EXT2_BLOCK_SIZE(fs);
793	sbp->f_blocks = fs->e2fs->e2fs_bcount - overhead;
794	sbp->f_bfree = fs->e2fs->e2fs_fbcount;
795	sbp->f_bavail = sbp->f_bfree - fs->e2fs->e2fs_rbcount;
796	sbp->f_files = fs->e2fs->e2fs_icount;
797	sbp->f_ffree = fs->e2fs->e2fs_ficount;
798	return (0);
799}
800
801/*
802 * Go through the disk queues to initiate sandbagged IO;
803 * go through the inodes to write those that have been modified;
804 * initiate the writing of the super block if it has been modified.
805 *
806 * Note: we are always called with the filesystem marked `MPBUSY'.
807 */
808static int
809ext2_sync(struct mount *mp, int waitfor)
810{
811	struct vnode *mvp, *vp;
812	struct thread *td;
813	struct inode *ip;
814	struct ext2mount *ump = VFSTOEXT2(mp);
815	struct m_ext2fs *fs;
816	int error, allerror = 0;
817
818	td = curthread;
819	fs = ump->um_e2fs;
820	if (fs->e2fs_fmod != 0 && fs->e2fs_ronly != 0) {		/* XXX */
821		printf("fs = %s\n", fs->e2fs_fsmnt);
822		panic("ext2_sync: rofs mod");
823	}
824
825	/*
826	 * Write back each (modified) inode.
827	 */
828loop:
829	MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
830		if (vp->v_type == VNON) {
831			VI_UNLOCK(vp);
832			continue;
833		}
834		ip = VTOI(vp);
835		if ((ip->i_flag &
836		    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
837		    (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
838		    waitfor == MNT_LAZY)) {
839			VI_UNLOCK(vp);
840			continue;
841		}
842		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
843		if (error) {
844			if (error == ENOENT) {
845				MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
846				goto loop;
847			}
848			continue;
849		}
850		if ((error = VOP_FSYNC(vp, waitfor, td)) != 0)
851			allerror = error;
852		VOP_UNLOCK(vp, 0);
853		vrele(vp);
854	}
855
856	/*
857	 * Force stale filesystem control information to be flushed.
858	 */
859	if (waitfor != MNT_LAZY) {
860		vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
861		if ((error = VOP_FSYNC(ump->um_devvp, waitfor, td)) != 0)
862			allerror = error;
863		VOP_UNLOCK(ump->um_devvp, 0);
864	}
865
866	/*
867	 * Write back modified superblock.
868	 */
869	if (fs->e2fs_fmod != 0) {
870		fs->e2fs_fmod = 0;
871		fs->e2fs->e2fs_wtime = time_second;
872		if ((error = ext2_cgupdate(ump, waitfor)) != 0)
873			allerror = error;
874	}
875	return (allerror);
876}
877
878/*
879 * Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
880 * in from disk.  If it is in core, wait for the lock bit to clear, then
881 * return the inode locked.  Detection and handling of mount points must be
882 * done by the calling routine.
883 */
884static int
885ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
886{
887	struct m_ext2fs *fs;
888	struct inode *ip;
889	struct ext2mount *ump;
890	struct buf *bp;
891	struct vnode *vp;
892	struct thread *td;
893	int i, error;
894	int used_blocks;
895
896	td = curthread;
897	error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
898	if (error || *vpp != NULL)
899		return (error);
900
901	ump = VFSTOEXT2(mp);
902	ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
903
904	/* Allocate a new vnode/inode. */
905	if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
906		*vpp = NULL;
907		free(ip, M_EXT2NODE);
908		return (error);
909	}
910	vp->v_data = ip;
911	ip->i_vnode = vp;
912	ip->i_e2fs = fs = ump->um_e2fs;
913	ip->i_ump  = ump;
914	ip->i_number = ino;
915
916	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
917	error = insmntque(vp, mp);
918	if (error != 0) {
919		free(ip, M_EXT2NODE);
920		*vpp = NULL;
921		return (error);
922	}
923	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
924	if (error || *vpp != NULL)
925		return (error);
926
927	/* Read in the disk contents for the inode, copy into the inode. */
928	if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
929	    (int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
930		/*
931		 * The inode does not contain anything useful, so it would
932		 * be misleading to leave it on its hash chain. With mode
933		 * still zero, it will be unlinked and returned to the free
934		 * list by vput().
935		 */
936		brelse(bp);
937		vput(vp);
938		*vpp = NULL;
939		return (error);
940	}
941	/* convert ext2 inode to dinode */
942	ext2_ei2i((struct ext2fs_dinode *) ((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
943			ino_to_fsbo(fs, ino)), ip);
944	ip->i_block_group = ino_to_cg(fs, ino);
945	ip->i_next_alloc_block = 0;
946	ip->i_next_alloc_goal = 0;
947
948	/*
949	 * Now we want to make sure that block pointers for unused
950	 * blocks are zeroed out - ext2_balloc depends on this
951	 * although for regular files and directories only
952	 *
953	 * If IN_E4EXTENTS is enabled, unused blocks are not zeroed
954	 * out because we could corrupt the extent tree.
955	 */
956	if (!(ip->i_flag & IN_E4EXTENTS) &&
957	    (S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode))) {
958		used_blocks = (ip->i_size+fs->e2fs_bsize-1) / fs->e2fs_bsize;
959		for (i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
960			ip->i_db[i] = 0;
961	}
962#ifdef EXT2FS_DEBUG
963	ext2_print_inode(ip);
964#endif
965	bqrelse(bp);
966
967	/*
968	 * Initialize the vnode from the inode, check for aliases.
969	 * Note that the underlying vnode may have changed.
970	 */
971	if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
972		vput(vp);
973		*vpp = NULL;
974		return (error);
975	}
976
977	/*
978	 * Finish inode initialization.
979	 */
980
981	/*
982	 * Set up a generation number for this inode if it does not
983	 * already have one. This should only happen on old filesystems.
984	 */
985	if (ip->i_gen == 0) {
986		ip->i_gen = random() + 1;
987		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
988			ip->i_flag |= IN_MODIFIED;
989	}
990	*vpp = vp;
991	return (0);
992}
993
994/*
995 * File handle to vnode
996 *
997 * Have to be really careful about stale file handles:
998 * - check that the inode number is valid
999 * - call ext2_vget() to get the locked inode
1000 * - check for an unallocated inode (i_mode == 0)
1001 * - check that the given client host has export rights and return
1002 *   those rights via. exflagsp and credanonp
1003 */
1004static int
1005ext2_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
1006{
1007	struct inode *ip;
1008	struct ufid *ufhp;
1009	struct vnode *nvp;
1010	struct m_ext2fs *fs;
1011	int error;
1012
1013	ufhp = (struct ufid *)fhp;
1014	fs = VFSTOEXT2(mp)->um_e2fs;
1015	if (ufhp->ufid_ino < EXT2_ROOTINO ||
1016	    ufhp->ufid_ino > fs->e2fs_gcount * fs->e2fs->e2fs_ipg)
1017		return (ESTALE);
1018
1019	error = VFS_VGET(mp, ufhp->ufid_ino, LK_EXCLUSIVE, &nvp);
1020	if (error) {
1021		*vpp = NULLVP;
1022		return (error);
1023	}
1024	ip = VTOI(nvp);
1025	if (ip->i_mode == 0 ||
1026	    ip->i_gen != ufhp->ufid_gen || ip->i_nlink <= 0) {
1027		vput(nvp);
1028		*vpp = NULLVP;
1029		return (ESTALE);
1030	}
1031	*vpp = nvp;
1032	vnode_create_vobject(*vpp, 0, curthread);
1033	return (0);
1034}
1035
1036/*
1037 * Write a superblock and associated information back to disk.
1038 */
1039static int
1040ext2_sbupdate(struct ext2mount *mp, int waitfor)
1041{
1042	struct m_ext2fs *fs = mp->um_e2fs;
1043	struct ext2fs *es = fs->e2fs;
1044	struct buf *bp;
1045	int error = 0;
1046
1047	bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0, 0);
1048	bcopy((caddr_t)es, bp->b_data, (u_int)sizeof(struct ext2fs));
1049	if (waitfor == MNT_WAIT)
1050		error = bwrite(bp);
1051	else
1052		bawrite(bp);
1053
1054	/*
1055	 * The buffers for group descriptors, inode bitmaps and block bitmaps
1056	 * are not busy at this point and are (hopefully) written by the
1057	 * usual sync mechanism. No need to write them here.
1058	 */
1059	return (error);
1060}
1061int
1062ext2_cgupdate(struct ext2mount *mp, int waitfor)
1063{
1064	struct m_ext2fs *fs = mp->um_e2fs;
1065	struct buf *bp;
1066	int i, error = 0, allerror = 0;
1067
1068	allerror = ext2_sbupdate(mp, waitfor);
1069	for (i = 0; i < fs->e2fs_gdbcount; i++) {
1070		bp = getblk(mp->um_devvp, fsbtodb(fs,
1071		    fs->e2fs->e2fs_first_dblock +
1072		    1 /* superblock */ + i), fs->e2fs_bsize, 0, 0, 0);
1073		e2fs_cgsave(&fs->e2fs_gd[
1074		    i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
1075		    (struct ext2_gd *)bp->b_data, fs->e2fs_bsize);
1076		if (waitfor == MNT_WAIT)
1077			error = bwrite(bp);
1078		else
1079			bawrite(bp);
1080	}
1081
1082	if (!allerror && error)
1083		allerror = error;
1084	return (allerror);
1085}
1086/*
1087 * Return the root of a filesystem.
1088 */
1089static int
1090ext2_root(struct mount *mp, int flags, struct vnode **vpp)
1091{
1092	struct vnode *nvp;
1093	int error;
1094
1095	error = VFS_VGET(mp, EXT2_ROOTINO, LK_EXCLUSIVE, &nvp);
1096	if (error)
1097		return (error);
1098	*vpp = nvp;
1099	return (0);
1100}
1101