ext2_vfsops.c revision 228539
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: head/sys/fs/ext2fs/ext2_vfsops.c 228539 2011-12-15 20:31:18Z 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/fcntl.h>
51#include <sys/malloc.h>
52#include <sys/stat.h>
53#include <sys/mutex.h>
54
55#include <geom/geom.h>
56#include <geom/geom_vfs.h>
57
58#include <fs/ext2fs/ext2_mount.h>
59#include <fs/ext2fs/inode.h>
60
61#include <fs/ext2fs/fs.h>
62#include <fs/ext2fs/ext2fs.h>
63#include <fs/ext2fs/ext2_dinode.h>
64#include <fs/ext2fs/ext2_extern.h>
65
66static int	ext2_flushfiles(struct mount *mp, int flags, struct thread *td);
67static int	ext2_mountfs(struct vnode *, struct mount *);
68static int	ext2_reload(struct mount *mp, struct thread *td);
69static int	ext2_sbupdate(struct ext2mount *, int);
70static int	ext2_cgupdate(struct ext2mount *, int);
71static vfs_unmount_t		ext2_unmount;
72static vfs_root_t		ext2_root;
73static vfs_statfs_t		ext2_statfs;
74static vfs_sync_t		ext2_sync;
75static vfs_vget_t		ext2_vget;
76static vfs_fhtovp_t		ext2_fhtovp;
77static vfs_mount_t		ext2_mount;
78
79MALLOC_DEFINE(M_EXT2NODE, "ext2_node", "EXT2 vnode private part");
80static MALLOC_DEFINE(M_EXT2MNT, "ext2_mount", "EXT2 mount structure");
81
82static struct vfsops ext2fs_vfsops = {
83	.vfs_fhtovp =		ext2_fhtovp,
84	.vfs_mount =		ext2_mount,
85	.vfs_root =		ext2_root,	/* root inode via vget */
86	.vfs_statfs =		ext2_statfs,
87	.vfs_sync =		ext2_sync,
88	.vfs_unmount =		ext2_unmount,
89	.vfs_vget =		ext2_vget,
90};
91
92VFS_SET(ext2fs_vfsops, ext2fs, 0);
93
94static int	ext2_check_sb_compat(struct ext2fs *es, struct cdev *dev,
95		    int ronly);
96static int	compute_sb_data(struct vnode * devvp,
97		    struct ext2fs * es, struct m_ext2fs * fs);
98
99static const char *ext2_opts[] = { "acls", "async", "noatime", "noclusterr",
100    "noclusterw", "noexec", "export", "force", "from", "multilabel",
101    "suiddir", "nosymfollow", "sync", "union", NULL };
102
103/*
104 * VFS Operations.
105 *
106 * mount system call
107 */
108static int
109ext2_mount(struct mount *mp)
110{
111	struct vfsoptlist *opts;
112	struct vnode *devvp;
113	struct thread *td;
114	struct ext2mount *ump = 0;
115	struct m_ext2fs *fs;
116	struct nameidata nd, *ndp = &nd;
117	accmode_t accmode;
118	char *path, *fspec;
119	int error, flags, len;
120
121	td = curthread;
122	opts = mp->mnt_optnew;
123
124	if (vfs_filteropt(opts, ext2_opts))
125		return (EINVAL);
126
127	vfs_getopt(opts, "fspath", (void **)&path, NULL);
128	/* Double-check the length of path.. */
129	if (strlen(path) >= MAXMNTLEN - 1)
130		return (ENAMETOOLONG);
131
132	fspec = NULL;
133	error = vfs_getopt(opts, "from", (void **)&fspec, &len);
134	if (!error && fspec[len - 1] != '\0')
135		return (EINVAL);
136
137	/*
138	 * If updating, check whether changing from read-only to
139	 * read/write; if there is no device name, that's all we do.
140	 */
141	if (mp->mnt_flag & MNT_UPDATE) {
142		ump = VFSTOEXT2(mp);
143		fs = ump->um_e2fs;
144		error = 0;
145		if (fs->e2fs_ronly == 0 &&
146		    vfs_flagopt(opts, "ro", NULL, 0)) {
147			error = VFS_SYNC(mp, MNT_WAIT);
148			if (error)
149				return (error);
150			flags = WRITECLOSE;
151			if (mp->mnt_flag & MNT_FORCE)
152				flags |= FORCECLOSE;
153			error = ext2_flushfiles(mp, flags, td);
154			if ( error == 0 && fs->e2fs_wasvalid && ext2_cgupdate(ump, MNT_WAIT) == 0) {
155				fs->e2fs->e2fs_state |= E2FS_ISCLEAN;
156				ext2_sbupdate(ump, MNT_WAIT);
157			}
158			fs->e2fs_ronly = 1;
159			vfs_flagopt(opts, "ro", &mp->mnt_flag, MNT_RDONLY);
160			DROP_GIANT();
161			g_topology_lock();
162			g_access(ump->um_cp, 0, -1, 0);
163			g_topology_unlock();
164			PICKUP_GIANT();
165		}
166		if (!error && (mp->mnt_flag & MNT_RELOAD))
167			error = ext2_reload(mp, td);
168		if (error)
169			return (error);
170		devvp = ump->um_devvp;
171		if (fs->e2fs_ronly && !vfs_flagopt(opts, "ro", NULL, 0)) {
172			if (ext2_check_sb_compat(fs->e2fs, devvp->v_rdev, 0))
173				return (EPERM);
174
175			/*
176			 * If upgrade to read-write by non-root, then verify
177			 * that user has necessary permissions on the device.
178			 */
179			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
180			error = VOP_ACCESS(devvp, VREAD | VWRITE,
181			    td->td_ucred, td);
182			if (error)
183				error = priv_check(td, PRIV_VFS_MOUNT_PERM);
184			if (error) {
185				VOP_UNLOCK(devvp, 0);
186				return (error);
187			}
188			VOP_UNLOCK(devvp, 0);
189			DROP_GIANT();
190			g_topology_lock();
191			error = g_access(ump->um_cp, 0, 1, 0);
192			g_topology_unlock();
193			PICKUP_GIANT();
194			if (error)
195				return (error);
196
197			if ((fs->e2fs->e2fs_state & E2FS_ISCLEAN) == 0 ||
198			    (fs->e2fs->e2fs_state & E2FS_ERRORS)) {
199				if (mp->mnt_flag & MNT_FORCE) {
200					printf(
201"WARNING: %s was not properly dismounted\n", fs->e2fs_fsmnt);
202				} else {
203					printf(
204"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
205					    fs->e2fs_fsmnt);
206					return (EPERM);
207				}
208			}
209			fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;
210			(void)ext2_cgupdate(ump, MNT_WAIT);
211			fs->e2fs_ronly = 0;
212			MNT_ILOCK(mp);
213			mp->mnt_flag &= ~MNT_RDONLY;
214			MNT_IUNLOCK(mp);
215		}
216		if (vfs_flagopt(opts, "export", NULL, 0)) {
217			/* Process export requests in vfs_mount.c. */
218			return (error);
219		}
220	}
221
222	/*
223	 * Not an update, or updating the name: look up the name
224	 * and verify that it refers to a sensible disk device.
225	 */
226	if (fspec == NULL)
227		return (EINVAL);
228	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
229	if ((error = namei(ndp)) != 0)
230		return (error);
231	NDFREE(ndp, NDF_ONLY_PNBUF);
232	devvp = ndp->ni_vp;
233
234	if (!vn_isdisk(devvp, &error)) {
235		vput(devvp);
236		return (error);
237	}
238
239	/*
240	 * If mount by non-root, then verify that user has necessary
241	 * permissions on the device.
242	 *
243	 * XXXRW: VOP_ACCESS() enough?
244	 */
245	accmode = VREAD;
246	if ((mp->mnt_flag & MNT_RDONLY) == 0)
247		accmode |= VWRITE;
248	error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
249	if (error)
250		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
251	if (error) {
252		vput(devvp);
253		return (error);
254	}
255
256	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
257		error = ext2_mountfs(devvp, mp);
258	} else {
259		if (devvp != ump->um_devvp) {
260			vput(devvp);
261			return (EINVAL);	/* needs translation */
262		} else
263			vput(devvp);
264	}
265	if (error) {
266		vrele(devvp);
267		return (error);
268	}
269	ump = VFSTOEXT2(mp);
270	fs = ump->um_e2fs;
271
272	/*
273	 * Note that this strncpy() is ok because of a check at the start
274	 * of ext2_mount().
275	 */
276	strncpy(fs->e2fs_fsmnt, path, MAXMNTLEN);
277	fs->e2fs_fsmnt[MAXMNTLEN - 1] = '\0';
278	vfs_mountedfrom(mp, fspec);
279	return (0);
280}
281
282static int
283ext2_check_sb_compat(struct ext2fs *es, struct cdev *dev, int ronly)
284{
285
286	if (es->e2fs_magic != E2FS_MAGIC) {
287		printf("ext2fs: %s: wrong magic number %#x (expected %#x)\n",
288		    devtoname(dev), es->e2fs_magic, E2FS_MAGIC);
289		return (1);
290	}
291	if (es->e2fs_rev > E2FS_REV0) {
292		if (es->e2fs_features_incompat & ~EXT2F_INCOMPAT_SUPP) {
293			printf(
294"WARNING: mount of %s denied due to unsupported optional features\n",
295			    devtoname(dev));
296			return (1);
297		}
298		if (!ronly &&
299		    (es->e2fs_features_rocompat & ~EXT2F_ROCOMPAT_SUPP)) {
300			printf("WARNING: R/W mount of %s denied due to "
301			    "unsupported optional features\n", devtoname(dev));
302			return (1);
303		}
304	}
305	return (0);
306}
307
308/*
309 * This computes the fields of the  ext2_sb_info structure from the
310 * data in the ext2_super_block structure read in.
311 */
312static int
313compute_sb_data(struct vnode *devvp, struct ext2fs *es,
314    struct m_ext2fs *fs)
315{
316	int db_count, error;
317	int i;
318	int logic_sb_block = 1;	/* XXX for now */
319	struct buf *bp;
320
321	fs->e2fs_bsize = EXT2_MIN_BLOCK_SIZE << es->e2fs_log_bsize;
322	fs->e2fs_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->e2fs_log_bsize;
323	fs->e2fs_fsbtodb = es->e2fs_log_bsize + 1;
324	fs->e2fs_qbmask = fs->e2fs_bsize - 1;
325	fs->e2fs_blocksize_bits = es->e2fs_log_bsize + 10;
326	fs->e2fs_fsize = EXT2_MIN_FRAG_SIZE << es->e2fs_log_fsize;
327	if (fs->e2fs_fsize)
328		fs->e2fs_fpb = fs->e2fs_bsize / fs->e2fs_fsize;
329	fs->e2fs_bpg = es->e2fs_bpg;
330	fs->e2fs_fpg = es->e2fs_fpg;
331	fs->e2fs_ipg = es->e2fs_ipg;
332	if (es->e2fs_rev == E2FS_REV0) {
333		fs->e2fs_first_inode = EXT2_FIRSTINO;
334		fs->e2fs_isize = E2FS_REV0_INODE_SIZE ;
335	} else {
336		fs->e2fs_first_inode = es->e2fs_first_ino;
337		fs->e2fs_isize = es->e2fs_inode_size;
338
339		/*
340		 * Simple sanity check for superblock inode size value.
341		 */
342		if (fs->e2fs_isize < E2FS_REV0_INODE_SIZE  ||
343		    fs->e2fs_isize > fs->e2fs_bsize ||
344		    (fs->e2fs_isize & (fs->e2fs_isize - 1)) != 0) {
345			printf("EXT2-fs: invalid inode size %d\n",
346			    fs->e2fs_isize);
347			return (EIO);
348		}
349	}
350	fs->e2fs_ipb = fs->e2fs_bsize / EXT2_INODE_SIZE(fs);
351	fs->e2fs_itpg = fs->e2fs_ipg /fs->e2fs_ipb;
352	fs->e2fs_descpb = fs->e2fs_bsize / sizeof (struct ext2_gd);
353	/* s_resuid / s_resgid ? */
354	fs->e2fs_gcount = (es->e2fs_bcount - es->e2fs_first_dblock +
355	    EXT2_BLOCKS_PER_GROUP(fs) - 1) / EXT2_BLOCKS_PER_GROUP(fs);
356	db_count = (fs->e2fs_gcount + EXT2_DESC_PER_BLOCK(fs) - 1) /
357	    EXT2_DESC_PER_BLOCK(fs);
358	fs->e2fs_gdbcount = db_count;
359	fs->e2fs_gd = malloc(db_count * fs->e2fs_bsize,
360	    M_EXT2MNT, M_WAITOK);
361	fs->e2fs_contigdirs = malloc(fs->e2fs_gcount * sizeof(*fs->e2fs_contigdirs),
362	    M_EXT2MNT, M_WAITOK);
363
364	/*
365	 * Adjust logic_sb_block.
366	 * Godmar thinks: if the blocksize is greater than 1024, then
367	 * the superblock is logically part of block zero.
368	 */
369	if(fs->e2fs_bsize > SBSIZE)
370		logic_sb_block = 0;
371	for (i = 0; i < db_count; i++) {
372		error = bread(devvp ,
373			 fsbtodb(fs, logic_sb_block + i + 1 ),
374			fs->e2fs_bsize, NOCRED, &bp);
375		if (error) {
376			free(fs->e2fs_gd, M_EXT2MNT);
377			brelse(bp);
378			return (error);
379		}
380		e2fs_cgload((struct ext2_gd *)bp->b_data,
381		    &fs->e2fs_gd[
382			i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
383		    fs->e2fs_bsize);
384		brelse(bp);
385		bp = NULL;
386	}
387	fs->e2fs_total_dir = 0;
388	for (i=0; i < fs->e2fs_gcount; i++){
389		fs->e2fs_total_dir += fs->e2fs_gd[i].ext2bgd_ndirs;
390		fs->e2fs_contigdirs[i] = 0;
391	}
392	if (es->e2fs_rev == E2FS_REV0 ||
393	    (es->e2fs_features_rocompat & EXT2F_ROCOMPAT_LARGEFILE) == 0)
394		fs->e2fs_maxfilesize = 0x7fffffff;
395	else
396		fs->e2fs_maxfilesize = 0x7fffffffffffffff;
397	return (0);
398}
399
400/*
401 * Reload all incore data for a filesystem (used after running fsck on
402 * the root filesystem and finding things to fix). The filesystem must
403 * be mounted read-only.
404 *
405 * Things to do to update the mount:
406 *	1) invalidate all cached meta-data.
407 *	2) re-read superblock from disk.
408 *	3) invalidate all cluster summary information.
409 *	4) invalidate all inactive vnodes.
410 *	5) invalidate all cached file data.
411 *	6) re-read inode data for all active vnodes.
412 * XXX we are missing some steps, in particular # 3, this has to be reviewed.
413 */
414static int
415ext2_reload(struct mount *mp, struct thread *td)
416{
417	struct vnode *vp, *mvp, *devvp;
418	struct inode *ip;
419	struct buf *bp;
420	struct ext2fs *es;
421	struct m_ext2fs *fs;
422	struct csum *sump;
423	int error, i;
424	int32_t *lp;
425
426	if ((mp->mnt_flag & MNT_RDONLY) == 0)
427		return (EINVAL);
428	/*
429	 * Step 1: invalidate all cached meta-data.
430	 */
431	devvp = VFSTOEXT2(mp)->um_devvp;
432	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
433	if (vinvalbuf(devvp, 0, 0, 0) != 0)
434		panic("ext2_reload: dirty1");
435	VOP_UNLOCK(devvp, 0);
436
437	/*
438	 * Step 2: re-read superblock from disk.
439	 * constants have been adjusted for ext2
440	 */
441	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
442		return (error);
443	es = (struct ext2fs *)bp->b_data;
444	if (ext2_check_sb_compat(es, devvp->v_rdev, 0) != 0) {
445		brelse(bp);
446		return (EIO);		/* XXX needs translation */
447	}
448	fs = VFSTOEXT2(mp)->um_e2fs;
449	bcopy(bp->b_data, fs->e2fs, sizeof(struct ext2fs));
450
451	if((error = compute_sb_data(devvp, es, fs)) != 0) {
452		brelse(bp);
453		return (error);
454	}
455#ifdef UNKLAR
456	if (fs->fs_sbsize < SBSIZE)
457		bp->b_flags |= B_INVAL;
458#endif
459	brelse(bp);
460
461	/*
462	 * Step 3: invalidate all cluster summary information.
463	 */
464	if (fs->e2fs_contigsumsize > 0) {
465		lp = fs->e2fs_maxcluster;
466		sump = fs->e2fs_clustersum;
467		for (i = 0; i < fs->e2fs_gcount; i++, sump++) {
468			*lp++ = fs->e2fs_contigsumsize;
469			sump->cs_init = 0;
470			bzero(sump->cs_sum, fs->e2fs_contigsumsize + 1);
471		}
472	}
473
474loop:
475	MNT_ILOCK(mp);
476	MNT_VNODE_FOREACH(vp, mp, mvp) {
477		VI_LOCK(vp);
478		if (vp->v_iflag & VI_DOOMED) {
479			VI_UNLOCK(vp);
480			continue;
481		}
482		MNT_IUNLOCK(mp);
483		/*
484		 * Step 4: invalidate all cached file data.
485		 */
486		if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
487			MNT_VNODE_FOREACH_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_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		MNT_ILOCK(mp);
511	}
512	MNT_IUNLOCK(mp);
513	return (0);
514}
515
516/*
517 * Common code for mount and mountroot.
518 */
519static int
520ext2_mountfs(struct vnode *devvp, struct mount *mp)
521{
522	struct ext2mount *ump;
523	struct buf *bp;
524	struct m_ext2fs *fs;
525	struct ext2fs *es;
526	struct cdev *dev = devvp->v_rdev;
527	struct g_consumer *cp;
528	struct bufobj *bo;
529	struct csum *sump;
530	int error;
531	int ronly;
532	int i, size;
533	int32_t *lp;
534
535	ronly = vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0);
536	/* XXX: use VOP_ACESS to check FS perms */
537	DROP_GIANT();
538	g_topology_lock();
539	error = g_vfs_open(devvp, &cp, "ext2fs", ronly ? 0 : 1);
540	g_topology_unlock();
541	PICKUP_GIANT();
542	VOP_UNLOCK(devvp, 0);
543	if (error)
544		return (error);
545
546	/* XXX: should we check for some sectorsize or 512 instead? */
547	if (((SBSIZE % cp->provider->sectorsize) != 0) ||
548	    (SBSIZE < cp->provider->sectorsize)) {
549		DROP_GIANT();
550		g_topology_lock();
551		g_vfs_close(cp);
552		g_topology_unlock();
553		PICKUP_GIANT();
554		return (EINVAL);
555	}
556
557	bo = &devvp->v_bufobj;
558	bo->bo_private = cp;
559	bo->bo_ops = g_vfs_bufops;
560	if (devvp->v_rdev->si_iosize_max != 0)
561		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
562	if (mp->mnt_iosize_max > MAXPHYS)
563		mp->mnt_iosize_max = MAXPHYS;
564
565	bp = NULL;
566	ump = NULL;
567	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
568		goto out;
569	es = (struct ext2fs *)bp->b_data;
570	if (ext2_check_sb_compat(es, dev, ronly) != 0) {
571		error = EINVAL;		/* XXX needs translation */
572		goto out;
573	}
574	if ((es->e2fs_state & E2FS_ISCLEAN) == 0 ||
575	    (es->e2fs_state & E2FS_ERRORS)) {
576		if (ronly || (mp->mnt_flag & MNT_FORCE)) {
577			printf(
578"WARNING: Filesystem was not properly dismounted\n");
579		} else {
580			printf(
581"WARNING: R/W mount denied.  Filesystem is not clean - run fsck\n");
582			error = EPERM;
583			goto out;
584		}
585	}
586	ump = malloc(sizeof *ump, M_EXT2MNT, M_WAITOK);
587	bzero((caddr_t)ump, sizeof *ump);
588
589	/*
590	 * I don't know whether this is the right strategy. Note that
591	 * we dynamically allocate both an ext2_sb_info and an ext2_super_block
592	 * while Linux keeps the super block in a locked buffer.
593	 */
594	ump->um_e2fs = malloc(sizeof(struct m_ext2fs),
595		M_EXT2MNT, M_WAITOK);
596	ump->um_e2fs->e2fs = malloc(sizeof(struct ext2fs),
597		M_EXT2MNT, M_WAITOK);
598	mtx_init(EXT2_MTX(ump), "EXT2FS", "EXT2FS Lock", MTX_DEF);
599	bcopy(es, ump->um_e2fs->e2fs, (u_int)sizeof(struct ext2fs));
600	if ((error = compute_sb_data(devvp, ump->um_e2fs->e2fs, ump->um_e2fs)))
601		goto out;
602
603	/*
604	 * Calculate the maximum contiguous blocks and size of cluster summary
605	 * array.  In FFS this is done by newfs; however the superblock in
606	 * ext2fs doesn't have these variables so we just can calculate
607	 * them here.
608	 */
609	ump->um_e2fs->e2fs_maxcontig = MAX(1, MAXPHYS / ump->um_e2fs->e2fs_bsize);
610	if (ump->um_e2fs->e2fs_maxcontig > 0)
611		ump->um_e2fs->e2fs_contigsumsize =
612		    MIN(ump->um_e2fs->e2fs_maxcontig, EXT2_MAXCONTIG);
613	else
614		ump->um_e2fs->e2fs_contigsumsize = 0;
615	if (ump->um_e2fs->e2fs_contigsumsize > 0) {
616		size = ump->um_e2fs->e2fs_gcount * sizeof(int32_t);
617		ump->um_e2fs->e2fs_maxcluster = malloc(size, M_EXT2MNT, M_WAITOK);
618		size = ump->um_e2fs->e2fs_gcount * sizeof(struct csum);
619		ump->um_e2fs->e2fs_clustersum = malloc(size, M_EXT2MNT, M_WAITOK);
620		lp = ump->um_e2fs->e2fs_maxcluster;
621		sump = ump->um_e2fs->e2fs_clustersum;
622		for (i = 0; i < ump->um_e2fs->e2fs_gcount; i++, sump++) {
623			*lp++ = ump->um_e2fs->e2fs_contigsumsize;
624			sump->cs_init = 0;
625			sump->cs_sum = malloc((ump->um_e2fs->e2fs_contigsumsize + 1) *
626			    sizeof(int32_t), M_EXT2MNT, M_WAITOK | M_ZERO);
627		}
628	}
629
630	brelse(bp);
631	bp = NULL;
632	fs = ump->um_e2fs;
633	fs->e2fs_ronly = ronly;	/* ronly is set according to mnt_flags */
634
635	/*
636	 * If the fs is not mounted read-only, make sure the super block is
637	 * always written back on a sync().
638	 */
639	fs->e2fs_wasvalid = fs->e2fs->e2fs_state & E2FS_ISCLEAN ? 1 : 0;
640	if (ronly == 0) {
641		fs->e2fs_fmod = 1;		/* mark it modified */
642		fs->e2fs->e2fs_state &= ~E2FS_ISCLEAN;	/* set fs invalid */
643	}
644	mp->mnt_data = ump;
645	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
646	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
647	mp->mnt_maxsymlinklen = EXT2_MAXSYMLINKLEN;
648	MNT_ILOCK(mp);
649	mp->mnt_flag |= MNT_LOCAL;
650	MNT_IUNLOCK(mp);
651	ump->um_mountp = mp;
652	ump->um_dev = dev;
653	ump->um_devvp = devvp;
654	ump->um_bo = &devvp->v_bufobj;
655	ump->um_cp = cp;
656
657	/*
658	 * Setting those two parameters allowed us to use
659	 * ufs_bmap w/o changse!
660	 */
661	ump->um_nindir = EXT2_ADDR_PER_BLOCK(fs);
662	ump->um_bptrtodb = fs->e2fs->e2fs_log_bsize + 1;
663	ump->um_seqinc = EXT2_FRAGS_PER_BLOCK(fs);
664	if (ronly == 0)
665		ext2_sbupdate(ump, MNT_WAIT);
666	/*
667	 * Initialize filesystem stat information in mount struct.
668	 */
669	MNT_ILOCK(mp);
670 	mp->mnt_kern_flag |= MNTK_MPSAFE | MNTK_LOOKUP_SHARED |
671            MNTK_EXTENDED_SHARED;
672	MNT_IUNLOCK(mp);
673	return (0);
674out:
675	if (bp)
676		brelse(bp);
677	if (cp != NULL) {
678		DROP_GIANT();
679		g_topology_lock();
680		g_vfs_close(cp);
681		g_topology_unlock();
682		PICKUP_GIANT();
683	}
684	if (ump) {
685	  	mtx_destroy(EXT2_MTX(ump));
686		free(ump->um_e2fs->e2fs_gd, M_EXT2MNT);
687		free(ump->um_e2fs->e2fs_contigdirs, M_EXT2MNT);
688		free(ump->um_e2fs->e2fs, M_EXT2MNT);
689		free(ump->um_e2fs, M_EXT2MNT);
690		free(ump, M_EXT2MNT);
691		mp->mnt_data = NULL;
692	}
693	return (error);
694}
695
696/*
697 * Unmount system call.
698 */
699static int
700ext2_unmount(struct mount *mp, int mntflags)
701{
702	struct ext2mount *ump;
703	struct m_ext2fs *fs;
704	struct csum *sump;
705	int error, flags, i, ronly;
706
707	flags = 0;
708	if (mntflags & MNT_FORCE) {
709		if (mp->mnt_flag & MNT_ROOTFS)
710			return (EINVAL);
711		flags |= FORCECLOSE;
712	}
713	if ((error = ext2_flushfiles(mp, flags, curthread)) != 0)
714		return (error);
715	ump = VFSTOEXT2(mp);
716	fs = ump->um_e2fs;
717	ronly = fs->e2fs_ronly;
718	if (ronly == 0 && ext2_cgupdate(ump, MNT_WAIT) == 0) {
719		if (fs->e2fs_wasvalid)
720 			fs->e2fs->e2fs_state |= E2FS_ISCLEAN;
721 		ext2_sbupdate(ump, MNT_WAIT);
722	}
723
724	DROP_GIANT();
725	g_topology_lock();
726	g_vfs_close(ump->um_cp);
727	g_topology_unlock();
728	PICKUP_GIANT();
729	vrele(ump->um_devvp);
730	sump = fs->e2fs_clustersum;
731	for (i = 0; i < fs->e2fs_gcount; i++, sump++)
732		free(sump->cs_sum, M_EXT2MNT);
733	free(fs->e2fs_clustersum, M_EXT2MNT);
734	free(fs->e2fs_maxcluster, M_EXT2MNT);
735	free(fs->e2fs_gd, M_EXT2MNT);
736	free(fs->e2fs_contigdirs, M_EXT2MNT);
737	free(fs->e2fs, M_EXT2MNT);
738	free(fs, M_EXT2MNT);
739	free(ump, M_EXT2MNT);
740	mp->mnt_data = NULL;
741	MNT_ILOCK(mp);
742	mp->mnt_flag &= ~MNT_LOCAL;
743	MNT_IUNLOCK(mp);
744	return (error);
745}
746
747/*
748 * Flush out all the files in a filesystem.
749 */
750static int
751ext2_flushfiles(struct mount *mp, int flags, struct thread *td)
752{
753	int error;
754
755	error = vflush(mp, 0, flags, td);
756	return (error);
757}
758/*
759 * Get file system statistics.
760 */
761int
762ext2_statfs(struct mount *mp, struct statfs *sbp)
763{
764	struct ext2mount *ump;
765	struct m_ext2fs *fs;
766	uint32_t overhead, overhead_per_group, ngdb;
767	int i, ngroups;
768
769	ump = VFSTOEXT2(mp);
770	fs = ump->um_e2fs;
771	if (fs->e2fs->e2fs_magic != E2FS_MAGIC)
772		panic("ext2fs_statvfs");
773
774	/*
775	 * Compute the overhead (FS structures)
776	 */
777	overhead_per_group =
778	    1 /* block bitmap */ +
779	    1 /* inode bitmap */ +
780	    fs->e2fs_itpg;
781	overhead = fs->e2fs->e2fs_first_dblock +
782	    fs->e2fs_gcount * overhead_per_group;
783	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
784	    fs->e2fs->e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) {
785		for (i = 0, ngroups = 0; i < fs->e2fs_gcount; i++) {
786			if (cg_has_sb(i))
787				ngroups++;
788		}
789	} else {
790		ngroups = fs->e2fs_gcount;
791	}
792	ngdb = fs->e2fs_gdbcount;
793	if (fs->e2fs->e2fs_rev > E2FS_REV0 &&
794	    fs->e2fs->e2fs_features_compat & EXT2F_COMPAT_RESIZE)
795		ngdb += fs->e2fs->e2fs_reserved_ngdb;
796	overhead += ngroups * (1 /* superblock */ + ngdb);
797
798	sbp->f_bsize = EXT2_FRAG_SIZE(fs);
799	sbp->f_iosize = EXT2_BLOCK_SIZE(fs);
800	sbp->f_blocks = fs->e2fs->e2fs_bcount - overhead;
801	sbp->f_bfree = fs->e2fs->e2fs_fbcount;
802	sbp->f_bavail = sbp->f_bfree - fs->e2fs->e2fs_rbcount;
803	sbp->f_files = fs->e2fs->e2fs_icount;
804	sbp->f_ffree = fs->e2fs->e2fs_ficount;
805	return (0);
806}
807
808/*
809 * Go through the disk queues to initiate sandbagged IO;
810 * go through the inodes to write those that have been modified;
811 * initiate the writing of the super block if it has been modified.
812 *
813 * Note: we are always called with the filesystem marked `MPBUSY'.
814 */
815static int
816ext2_sync(struct mount *mp, int waitfor)
817{
818	struct vnode *mvp, *vp;
819	struct thread *td;
820	struct inode *ip;
821	struct ext2mount *ump = VFSTOEXT2(mp);
822	struct m_ext2fs *fs;
823	int error, allerror = 0;
824
825	td = curthread;
826	fs = ump->um_e2fs;
827	if (fs->e2fs_fmod != 0 && fs->e2fs_ronly != 0) {		/* XXX */
828		printf("fs = %s\n", fs->e2fs_fsmnt);
829		panic("ext2_sync: rofs mod");
830	}
831
832	/*
833	 * Write back each (modified) inode.
834	 */
835	MNT_ILOCK(mp);
836loop:
837	MNT_VNODE_FOREACH(vp, mp, mvp) {
838		VI_LOCK(vp);
839		if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) {
840			VI_UNLOCK(vp);
841			continue;
842		}
843		MNT_IUNLOCK(mp);
844		ip = VTOI(vp);
845		if ((ip->i_flag &
846		    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
847		    (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
848		    waitfor == MNT_LAZY)) {
849			VI_UNLOCK(vp);
850			MNT_ILOCK(mp);
851			continue;
852		}
853		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
854		if (error) {
855			MNT_ILOCK(mp);
856			if (error == ENOENT) {
857				MNT_VNODE_FOREACH_ABORT_ILOCKED(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		MNT_ILOCK(mp);
867	}
868	MNT_IUNLOCK(mp);
869
870	/*
871	 * Force stale file system control information to be flushed.
872	 */
873	if (waitfor != MNT_LAZY) {
874		vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
875		if ((error = VOP_FSYNC(ump->um_devvp, waitfor, td)) != 0)
876			allerror = error;
877		VOP_UNLOCK(ump->um_devvp, 0);
878	}
879
880	/*
881	 * Write back modified superblock.
882	 */
883	if (fs->e2fs_fmod != 0) {
884		fs->e2fs_fmod = 0;
885		fs->e2fs->e2fs_wtime = time_second;
886		if ((error = ext2_cgupdate(ump, waitfor)) != 0)
887			allerror = error;
888	}
889	return (allerror);
890}
891
892/*
893 * Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
894 * in from disk.  If it is in core, wait for the lock bit to clear, then
895 * return the inode locked.  Detection and handling of mount points must be
896 * done by the calling routine.
897 */
898static int
899ext2_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
900{
901	struct m_ext2fs *fs;
902	struct inode *ip;
903	struct ext2mount *ump;
904	struct buf *bp;
905	struct vnode *vp;
906	struct cdev *dev;
907	struct thread *td;
908	int i, error;
909	int used_blocks;
910
911	td = curthread;
912	error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
913	if (error || *vpp != NULL)
914		return (error);
915
916	ump = VFSTOEXT2(mp);
917	dev = ump->um_dev;
918
919	/*
920	 * If this malloc() is performed after the getnewvnode()
921	 * it might block, leaving a vnode with a NULL v_data to be
922	 * found by ext2_sync() if a sync happens to fire right then,
923	 * which will cause a panic because ext2_sync() blindly
924	 * dereferences vp->v_data (as well it should).
925	 */
926	ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
927
928	/* Allocate a new vnode/inode. */
929	if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
930		*vpp = NULL;
931		free(ip, M_EXT2NODE);
932		return (error);
933	}
934	vp->v_data = ip;
935	ip->i_vnode = vp;
936	ip->i_e2fs = fs = ump->um_e2fs;
937	ip->i_ump  = ump;
938	ip->i_number = ino;
939
940	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
941	error = insmntque(vp, mp);
942	if (error != 0) {
943		free(ip, M_EXT2NODE);
944		*vpp = NULL;
945		return (error);
946	}
947	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
948	if (error || *vpp != NULL)
949		return (error);
950
951	/* Read in the disk contents for the inode, copy into the inode. */
952	if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
953	    (int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
954		/*
955		 * The inode does not contain anything useful, so it would
956		 * be misleading to leave it on its hash chain. With mode
957		 * still zero, it will be unlinked and returned to the free
958		 * list by vput().
959		 */
960		brelse(bp);
961		vput(vp);
962		*vpp = NULL;
963		return (error);
964	}
965	/* convert ext2 inode to dinode */
966	ext2_ei2i((struct ext2fs_dinode *) ((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
967			ino_to_fsbo(fs, ino)), ip);
968	ip->i_block_group = ino_to_cg(fs, ino);
969	ip->i_next_alloc_block = 0;
970	ip->i_next_alloc_goal = 0;
971	ip->i_prealloc_count = 0;
972	ip->i_prealloc_block = 0;
973
974	/*
975	 * Now we want to make sure that block pointers for unused
976	 * blocks are zeroed out - ext2_balloc depends on this
977	 * although for regular files and directories only
978	 */
979	if(S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode)) {
980		used_blocks = (ip->i_size+fs->e2fs_bsize-1) / fs->e2fs_bsize;
981		for(i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
982			ip->i_db[i] = 0;
983	}
984/*
985	ext2_print_inode(ip);
986*/
987	bqrelse(bp);
988
989	/*
990	 * Initialize the vnode from the inode, check for aliases.
991	 * Note that the underlying vnode may have changed.
992	 */
993	if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
994		vput(vp);
995		*vpp = NULL;
996		return (error);
997	}
998
999	/*
1000	 * Finish inode initialization.
1001	 */
1002
1003	/*
1004	 * Set up a generation number for this inode if it does not
1005	 * already have one. This should only happen on old filesystems.
1006	 */
1007	if (ip->i_gen == 0) {
1008		ip->i_gen = random() / 2 + 1;
1009		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
1010			ip->i_flag |= IN_MODIFIED;
1011	}
1012	*vpp = vp;
1013	return (0);
1014}
1015
1016/*
1017 * File handle to vnode
1018 *
1019 * Have to be really careful about stale file handles:
1020 * - check that the inode number is valid
1021 * - call ext2_vget() to get the locked inode
1022 * - check for an unallocated inode (i_mode == 0)
1023 * - check that the given client host has export rights and return
1024 *   those rights via. exflagsp and credanonp
1025 */
1026static int
1027ext2_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
1028{
1029	struct inode *ip;
1030	struct ufid *ufhp;
1031	struct vnode *nvp;
1032	struct m_ext2fs *fs;
1033	int error;
1034
1035	ufhp = (struct ufid *)fhp;
1036	fs = VFSTOEXT2(mp)->um_e2fs;
1037	if (ufhp->ufid_ino < EXT2_ROOTINO ||
1038	    ufhp->ufid_ino > fs->e2fs_gcount * fs->e2fs->e2fs_ipg)
1039		return (ESTALE);
1040
1041	error = VFS_VGET(mp, ufhp->ufid_ino, LK_EXCLUSIVE, &nvp);
1042	if (error) {
1043		*vpp = NULLVP;
1044		return (error);
1045	}
1046	ip = VTOI(nvp);
1047	if (ip->i_mode == 0 ||
1048	    ip->i_gen != ufhp->ufid_gen || ip->i_nlink <= 0) {
1049		vput(nvp);
1050		*vpp = NULLVP;
1051		return (ESTALE);
1052	}
1053	*vpp = nvp;
1054	vnode_create_vobject(*vpp, 0, curthread);
1055	return (0);
1056}
1057
1058/*
1059 * Write a superblock and associated information back to disk.
1060 */
1061static int
1062ext2_sbupdate(struct ext2mount *mp, int waitfor)
1063{
1064	struct m_ext2fs *fs = mp->um_e2fs;
1065	struct ext2fs *es = fs->e2fs;
1066	struct buf *bp;
1067	int error = 0;
1068
1069	bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0, 0);
1070	bcopy((caddr_t)es, bp->b_data, (u_int)sizeof(struct ext2fs));
1071	if (waitfor == MNT_WAIT)
1072		error = bwrite(bp);
1073	else
1074		bawrite(bp);
1075
1076	/*
1077	 * The buffers for group descriptors, inode bitmaps and block bitmaps
1078	 * are not busy at this point and are (hopefully) written by the
1079	 * usual sync mechanism. No need to write them here.
1080	 */
1081	return (error);
1082}
1083int
1084ext2_cgupdate(struct ext2mount *mp, int waitfor)
1085{
1086	struct m_ext2fs *fs = mp->um_e2fs;
1087	struct buf *bp;
1088	int i, error = 0, allerror = 0;
1089
1090	allerror = ext2_sbupdate(mp, waitfor);
1091	for (i = 0; i < fs->e2fs_gdbcount; i++) {
1092		bp = getblk(mp->um_devvp, fsbtodb(fs,
1093		    fs->e2fs->e2fs_first_dblock +
1094		    1 /* superblock */ + i), fs->e2fs_bsize, 0, 0, 0);
1095		e2fs_cgsave(&fs->e2fs_gd[
1096		    i * fs->e2fs_bsize / sizeof(struct ext2_gd)],
1097		    (struct ext2_gd *)bp->b_data, fs->e2fs_bsize);
1098		if (waitfor == MNT_WAIT)
1099			error = bwrite(bp);
1100		else
1101			bawrite(bp);
1102	}
1103
1104	if (!allerror && error)
1105		allerror = error;
1106	return (allerror);
1107}
1108/*
1109 * Return the root of a filesystem.
1110 */
1111static int
1112ext2_root(struct mount *mp, int flags, struct vnode **vpp)
1113{
1114	struct vnode *nvp;
1115	int error;
1116
1117	error = VFS_VGET(mp, EXT2_ROOTINO, LK_EXCLUSIVE, &nvp);
1118	if (error)
1119		return (error);
1120	*vpp = nvp;
1121	return (0);
1122}
1123