ext2_vfsops.c revision 187397
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/gnu/fs/ext2fs/ext2_vfsops.c 187397 2009-01-18 15:10:46Z stas $
37 */
38
39/*-
40 * COPYRIGHT.INFO says this has some GPL'd code from ext2_super.c in it
41 *
42 *      This program is free software; you can redistribute it and/or modify
43 *      it under the terms of the GNU General Public License as published by
44 *      the Free Software Foundation; either version 2 of the License.
45 *
46 *      This program is distributed in the hope that it will be useful,
47 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
48 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
49 *      GNU General Public License for more details.
50 *
51 *      You should have received a copy of the GNU General Public License
52 *      along with this program; if not, write to the Free Software
53 *      Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
54 *
55 */
56
57#include <sys/param.h>
58#include <sys/systm.h>
59#include <sys/namei.h>
60#include <sys/priv.h>
61#include <sys/proc.h>
62#include <sys/kernel.h>
63#include <sys/vnode.h>
64#include <sys/mount.h>
65#include <sys/bio.h>
66#include <sys/buf.h>
67#include <sys/conf.h>
68#include <sys/fcntl.h>
69#include <sys/malloc.h>
70#include <sys/stat.h>
71#include <sys/mutex.h>
72
73#include <geom/geom.h>
74#include <geom/geom_vfs.h>
75
76#include <gnu/fs/ext2fs/ext2_mount.h>
77#include <gnu/fs/ext2fs/inode.h>
78
79#include <gnu/fs/ext2fs/fs.h>
80#include <gnu/fs/ext2fs/ext2_extern.h>
81#include <gnu/fs/ext2fs/ext2_fs.h>
82#include <gnu/fs/ext2fs/ext2_fs_sb.h>
83
84static int ext2_flushfiles(struct mount *mp, int flags, struct thread *td);
85static int ext2_mountfs(struct vnode *, struct mount *);
86static int ext2_reload(struct mount *mp, struct thread *td);
87static int ext2_sbupdate(struct ext2mount *, int);
88
89static vfs_unmount_t		ext2_unmount;
90static vfs_root_t		ext2_root;
91static vfs_statfs_t		ext2_statfs;
92static vfs_sync_t		ext2_sync;
93static vfs_vget_t		ext2_vget;
94static vfs_fhtovp_t		ext2_fhtovp;
95static vfs_mount_t		ext2_mount;
96
97MALLOC_DEFINE(M_EXT2NODE, "ext2_node", "EXT2 vnode private part");
98static MALLOC_DEFINE(M_EXT2MNT, "ext2_mount", "EXT2 mount structure");
99
100static struct vfsops ext2fs_vfsops = {
101	.vfs_fhtovp =		ext2_fhtovp,
102	.vfs_mount =		ext2_mount,
103	.vfs_root =		ext2_root,	/* root inode via vget */
104	.vfs_statfs =		ext2_statfs,
105	.vfs_sync =		ext2_sync,
106	.vfs_unmount =		ext2_unmount,
107	.vfs_vget =		ext2_vget,
108};
109
110VFS_SET(ext2fs_vfsops, ext2fs, 0);
111
112#define bsd_malloc malloc
113#define bsd_free free
114
115static int	ext2_check_sb_compat(struct ext2_super_block *es, struct cdev *dev,
116		    int ronly);
117static int	compute_sb_data(struct vnode * devvp,
118		    struct ext2_super_block * es, struct ext2_sb_info * fs);
119
120static const char *ext2_opts[] = { "from", "export", "acls", "noexec",
121    "noatime", "union", "suiddir", "multilabel", "nosymfollow",
122    "noclusterr", "noclusterw", "force", NULL };
123
124/*
125 * VFS Operations.
126 *
127 * mount system call
128 */
129static int
130ext2_mount(mp, td)
131	struct mount *mp;
132	struct thread *td;
133{
134	struct vfsoptlist *opts;
135	struct vnode *devvp;
136	struct ext2mount *ump = 0;
137	struct ext2_sb_info *fs;
138	char *path, *fspec;
139	int error, flags, len;
140	accmode_t accmode;
141	struct nameidata nd, *ndp = &nd;
142
143	opts = mp->mnt_optnew;
144
145	if (vfs_filteropt(opts, ext2_opts))
146		return (EINVAL);
147
148	vfs_getopt(opts, "fspath", (void **)&path, NULL);
149	/* Double-check the length of path.. */
150	if (strlen(path) >= MAXMNTLEN - 1)
151		return (ENAMETOOLONG);
152
153	fspec = NULL;
154	error = vfs_getopt(opts, "from", (void **)&fspec, &len);
155	if (!error && fspec[len - 1] != '\0')
156		return (EINVAL);
157
158	/*
159	 * If updating, check whether changing from read-only to
160	 * read/write; if there is no device name, that's all we do.
161	 */
162	if (mp->mnt_flag & MNT_UPDATE) {
163		ump = VFSTOEXT2(mp);
164		fs = ump->um_e2fs;
165		error = 0;
166		if (fs->s_rd_only == 0 &&
167		    vfs_flagopt(opts, "ro", NULL, 0)) {
168			error = VFS_SYNC(mp, MNT_WAIT, td);
169			if (error)
170				return (error);
171			flags = WRITECLOSE;
172			if (mp->mnt_flag & MNT_FORCE)
173				flags |= FORCECLOSE;
174			if (vfs_busy(mp, MBF_NOWAIT))
175				return (EBUSY);
176			error = ext2_flushfiles(mp, flags, td);
177			vfs_unbusy(mp);
178			if (!error && fs->s_wasvalid) {
179				fs->s_es->s_state |= EXT2_VALID_FS;
180				ext2_sbupdate(ump, MNT_WAIT);
181			}
182			fs->s_rd_only = 1;
183			vfs_flagopt(opts, "ro", &mp->mnt_flag, MNT_RDONLY);
184			DROP_GIANT();
185			g_topology_lock();
186			g_access(ump->um_cp, 0, -1, 0);
187			g_topology_unlock();
188			PICKUP_GIANT();
189		}
190		if (!error && (mp->mnt_flag & MNT_RELOAD))
191			error = ext2_reload(mp, td);
192		if (error)
193			return (error);
194		devvp = ump->um_devvp;
195		if (fs->s_rd_only && !vfs_flagopt(opts, "ro", NULL, 0)) {
196			if (ext2_check_sb_compat(fs->s_es, devvp->v_rdev, 0))
197				return (EPERM);
198			/*
199			 * If upgrade to read-write by non-root, then verify
200			 * that user has necessary permissions on the device.
201			 */
202			vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
203			error = VOP_ACCESS(devvp, VREAD | VWRITE,
204			    td->td_ucred, td);
205			if (error)
206				error = priv_check(td, PRIV_VFS_MOUNT_PERM);
207			if (error) {
208				VOP_UNLOCK(devvp, 0);
209				return (error);
210			}
211			VOP_UNLOCK(devvp, 0);
212			DROP_GIANT();
213			g_topology_lock();
214			error = g_access(ump->um_cp, 0, 1, 0);
215			g_topology_unlock();
216			PICKUP_GIANT();
217			if (error)
218				return (error);
219
220			if ((fs->s_es->s_state & EXT2_VALID_FS) == 0 ||
221			    (fs->s_es->s_state & EXT2_ERROR_FS)) {
222				if (mp->mnt_flag & MNT_FORCE) {
223					printf(
224"WARNING: %s was not properly dismounted\n",
225					    fs->fs_fsmnt);
226				} else {
227					printf(
228"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
229					    fs->fs_fsmnt);
230					return (EPERM);
231				}
232			}
233			fs->s_es->s_state &= ~EXT2_VALID_FS;
234			ext2_sbupdate(ump, MNT_WAIT);
235			fs->s_rd_only = 0;
236			MNT_ILOCK(mp);
237			mp->mnt_flag &= ~MNT_RDONLY;
238			MNT_IUNLOCK(mp);
239		}
240		if (vfs_flagopt(opts, "export", NULL, 0)) {
241			/* Process export requests in vfs_mount.c. */
242			return (error);
243		}
244	}
245	/*
246	 * Not an update, or updating the name: look up the name
247	 * and verify that it refers to a sensible disk device.
248	 */
249	if (fspec == NULL)
250		return (EINVAL);
251	NDINIT(ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec, td);
252	if ((error = namei(ndp)) != 0)
253		return (error);
254	NDFREE(ndp, NDF_ONLY_PNBUF);
255	devvp = ndp->ni_vp;
256
257	if (!vn_isdisk(devvp, &error)) {
258		vput(devvp);
259		return (error);
260	}
261
262	/*
263	 * If mount by non-root, then verify that user has necessary
264	 * permissions on the device.
265	 *
266	 * XXXRW: VOP_ACCESS() enough?
267	 */
268	accmode = VREAD;
269	if ((mp->mnt_flag & MNT_RDONLY) == 0)
270		accmode |= VWRITE;
271	error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
272	if (error)
273		error = priv_check(td, PRIV_VFS_MOUNT_PERM);
274	if (error) {
275		vput(devvp);
276		return (error);
277	}
278
279	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
280		error = ext2_mountfs(devvp, mp);
281	} else {
282		if (devvp != ump->um_devvp) {
283			vput(devvp);
284			return (EINVAL);	/* needs translation */
285		} else
286			vput(devvp);
287	}
288	if (error) {
289		vrele(devvp);
290		return (error);
291	}
292	ump = VFSTOEXT2(mp);
293	fs = ump->um_e2fs;
294	/*
295	 * Note that this strncpy() is ok because of a check at the start
296	 * of ext2_mount().
297	 */
298	strncpy(fs->fs_fsmnt, path, MAXMNTLEN);
299	fs->fs_fsmnt[MAXMNTLEN - 1] = '\0';
300	vfs_mountedfrom(mp, fspec);
301	return (0);
302}
303
304/*
305 * checks that the data in the descriptor blocks make sense
306 * this is taken from ext2/super.c
307 */
308static int ext2_check_descriptors (struct ext2_sb_info * sb)
309{
310        int i;
311        int desc_block = 0;
312        unsigned long block = sb->s_es->s_first_data_block;
313        struct ext2_group_desc * gdp = NULL;
314
315        /* ext2_debug ("Checking group descriptors"); */
316
317        for (i = 0; i < sb->s_groups_count; i++)
318        {
319		/* examine next descriptor block */
320                if ((i % EXT2_DESC_PER_BLOCK(sb)) == 0)
321                        gdp = (struct ext2_group_desc *)
322				sb->s_group_desc[desc_block++]->b_data;
323                if (gdp->bg_block_bitmap < block ||
324                    gdp->bg_block_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
325                {
326                        printf ("ext2_check_descriptors: "
327                                    "Block bitmap for group %d"
328                                    " not in group (block %lu)!\n",
329                                    i, (unsigned long) gdp->bg_block_bitmap);
330                        return 0;
331                }
332                if (gdp->bg_inode_bitmap < block ||
333                    gdp->bg_inode_bitmap >= block + EXT2_BLOCKS_PER_GROUP(sb))
334                {
335                        printf ("ext2_check_descriptors: "
336                                    "Inode bitmap for group %d"
337                                    " not in group (block %lu)!\n",
338                                    i, (unsigned long) gdp->bg_inode_bitmap);
339                        return 0;
340                }
341                if (gdp->bg_inode_table < block ||
342                    gdp->bg_inode_table + sb->s_itb_per_group >=
343                    block + EXT2_BLOCKS_PER_GROUP(sb))
344                {
345                        printf ("ext2_check_descriptors: "
346                                    "Inode table for group %d"
347                                    " not in group (block %lu)!\n",
348                                    i, (unsigned long) gdp->bg_inode_table);
349                        return 0;
350                }
351                block += EXT2_BLOCKS_PER_GROUP(sb);
352                gdp++;
353        }
354        return 1;
355}
356
357static int
358ext2_check_sb_compat(es, dev, ronly)
359	struct ext2_super_block *es;
360	struct cdev *dev;
361	int ronly;
362{
363
364	if (es->s_magic != EXT2_SUPER_MAGIC) {
365		printf("ext2fs: %s: wrong magic number %#x (expected %#x)\n",
366		    devtoname(dev), es->s_magic, EXT2_SUPER_MAGIC);
367		return (1);
368	}
369	if (es->s_rev_level > EXT2_GOOD_OLD_REV) {
370		if (es->s_feature_incompat & ~EXT2_FEATURE_INCOMPAT_SUPP) {
371			printf(
372"WARNING: mount of %s denied due to unsupported optional features\n",
373			    devtoname(dev));
374			return (1);
375		}
376		if (!ronly &&
377		    (es->s_feature_ro_compat & ~EXT2_FEATURE_RO_COMPAT_SUPP)) {
378			printf(
379"WARNING: R/W mount of %s denied due to unsupported optional features\n",
380			    devtoname(dev));
381			return (1);
382		}
383	}
384	return (0);
385}
386
387/*
388 * this computes the fields of the  ext2_sb_info structure from the
389 * data in the ext2_super_block structure read in
390 */
391static int compute_sb_data(devvp, es, fs)
392	struct vnode * devvp;
393	struct ext2_super_block * es;
394	struct ext2_sb_info * fs;
395{
396    int db_count, error;
397    int i, j;
398    int logic_sb_block = 1;	/* XXX for now */
399
400#if 1
401#define V(v)
402#else
403#define V(v)  printf(#v"= %lu\n", (unsigned long)fs->v);
404#endif
405
406    fs->s_blocksize = EXT2_MIN_BLOCK_SIZE << es->s_log_block_size;
407    V(s_blocksize)
408    fs->s_bshift = EXT2_MIN_BLOCK_LOG_SIZE + es->s_log_block_size;
409    V(s_bshift)
410    fs->s_fsbtodb = es->s_log_block_size + 1;
411    V(s_fsbtodb)
412    fs->s_qbmask = fs->s_blocksize - 1;
413    V(s_qbmask)
414    fs->s_blocksize_bits = EXT2_BLOCK_SIZE_BITS(es);
415    V(s_blocksize_bits)
416    fs->s_frag_size = EXT2_MIN_FRAG_SIZE << es->s_log_frag_size;
417    V(s_frag_size)
418    if (fs->s_frag_size)
419	fs->s_frags_per_block = fs->s_blocksize / fs->s_frag_size;
420    V(s_frags_per_block)
421    fs->s_blocks_per_group = es->s_blocks_per_group;
422    V(s_blocks_per_group)
423    fs->s_frags_per_group = es->s_frags_per_group;
424    V(s_frags_per_group)
425    fs->s_inodes_per_group = es->s_inodes_per_group;
426    V(s_inodes_per_group)
427    fs->s_inode_size = es->s_inode_size;
428    V(s_inode_size)
429    fs->s_first_inode = es->s_first_ino;
430    V(s_first_inode);
431    fs->s_inodes_per_block = fs->s_blocksize / EXT2_INODE_SIZE(fs);
432    V(s_inodes_per_block)
433    fs->s_itb_per_group = fs->s_inodes_per_group /fs->s_inodes_per_block;
434    V(s_itb_per_group)
435    fs->s_desc_per_block = fs->s_blocksize / sizeof (struct ext2_group_desc);
436    V(s_desc_per_block)
437    /* s_resuid / s_resgid ? */
438    fs->s_groups_count = (es->s_blocks_count -
439			  es->s_first_data_block +
440			  EXT2_BLOCKS_PER_GROUP(fs) - 1) /
441			 EXT2_BLOCKS_PER_GROUP(fs);
442    V(s_groups_count)
443    db_count = (fs->s_groups_count + EXT2_DESC_PER_BLOCK(fs) - 1) /
444	EXT2_DESC_PER_BLOCK(fs);
445    fs->s_db_per_group = db_count;
446    V(s_db_per_group)
447
448    fs->s_group_desc = bsd_malloc(db_count * sizeof (struct buf *),
449		M_EXT2MNT, M_WAITOK);
450
451    /* adjust logic_sb_block */
452    if(fs->s_blocksize > SBSIZE)
453	/* Godmar thinks: if the blocksize is greater than 1024, then
454	   the superblock is logically part of block zero.
455	 */
456        logic_sb_block = 0;
457
458    for (i = 0; i < db_count; i++) {
459	error = bread(devvp , fsbtodb(fs, logic_sb_block + i + 1),
460		fs->s_blocksize, NOCRED, &fs->s_group_desc[i]);
461	if(error) {
462	    for (j = 0; j < i; j++)
463		brelse(fs->s_group_desc[j]);
464	    bsd_free(fs->s_group_desc, M_EXT2MNT);
465	    printf("EXT2-fs: unable to read group descriptors (%d)\n", error);
466	    return EIO;
467	}
468	LCK_BUF(fs->s_group_desc[i])
469    }
470    if(!ext2_check_descriptors(fs)) {
471	    for (j = 0; j < db_count; j++)
472		    ULCK_BUF(fs->s_group_desc[j])
473	    bsd_free(fs->s_group_desc, M_EXT2MNT);
474	    printf("EXT2-fs: (ext2_check_descriptors failure) "
475		   "unable to read group descriptors\n");
476	    return EIO;
477    }
478
479    for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++) {
480	    fs->s_inode_bitmap_number[i] = 0;
481	    fs->s_inode_bitmap[i] = NULL;
482	    fs->s_block_bitmap_number[i] = 0;
483	    fs->s_block_bitmap[i] = NULL;
484    }
485    fs->s_loaded_inode_bitmaps = 0;
486    fs->s_loaded_block_bitmaps = 0;
487    if (es->s_rev_level == EXT2_GOOD_OLD_REV || (es->s_feature_ro_compat &
488        EXT2_FEATURE_RO_COMPAT_LARGE_FILE) == 0)
489	fs->fs_maxfilesize = 0x7fffffff;
490    else
491	fs->fs_maxfilesize = 0x7fffffffffffffff;
492    return 0;
493}
494
495/*
496 * Reload all incore data for a filesystem (used after running fsck on
497 * the root filesystem and finding things to fix). The filesystem must
498 * be mounted read-only.
499 *
500 * Things to do to update the mount:
501 *	1) invalidate all cached meta-data.
502 *	2) re-read superblock from disk.
503 *	3) re-read summary information from disk.
504 *	4) invalidate all inactive vnodes.
505 *	5) invalidate all cached file data.
506 *	6) re-read inode data for all active vnodes.
507 */
508static int
509ext2_reload(struct mount *mp, struct thread *td)
510{
511	struct vnode *vp, *mvp, *devvp;
512	struct inode *ip;
513	struct buf *bp;
514	struct ext2_super_block * es;
515	struct ext2_sb_info *fs;
516	int error;
517
518	if ((mp->mnt_flag & MNT_RDONLY) == 0)
519		return (EINVAL);
520	/*
521	 * Step 1: invalidate all cached meta-data.
522	 */
523	devvp = VFSTOEXT2(mp)->um_devvp;
524	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
525	if (vinvalbuf(devvp, 0, 0, 0) != 0)
526		panic("ext2_reload: dirty1");
527	VOP_UNLOCK(devvp, 0);
528
529	/*
530	 * Step 2: re-read superblock from disk.
531	 * constants have been adjusted for ext2
532	 */
533	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
534		return (error);
535	es = (struct ext2_super_block *)bp->b_data;
536	if (ext2_check_sb_compat(es, devvp->v_rdev, 0) != 0) {
537		brelse(bp);
538		return (EIO);		/* XXX needs translation */
539	}
540	fs = VFSTOEXT2(mp)->um_e2fs;
541	bcopy(bp->b_data, fs->s_es, sizeof(struct ext2_super_block));
542
543	if((error = compute_sb_data(devvp, es, fs)) != 0) {
544		brelse(bp);
545		return error;
546	}
547#ifdef UNKLAR
548	if (fs->fs_sbsize < SBSIZE)
549		bp->b_flags |= B_INVAL;
550#endif
551	brelse(bp);
552
553loop:
554	MNT_ILOCK(mp);
555	MNT_VNODE_FOREACH(vp, mp, mvp) {
556		VI_LOCK(vp);
557		if (vp->v_iflag & VI_DOOMED) {
558			VI_UNLOCK(vp);
559			continue;
560		}
561		MNT_IUNLOCK(mp);
562		/*
563		 * Step 4: invalidate all cached file data.
564		 */
565		if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
566			MNT_VNODE_FOREACH_ABORT(mp, mvp);
567			goto loop;
568		}
569		if (vinvalbuf(vp, 0, 0, 0))
570			panic("ext2_reload: dirty2");
571		/*
572		 * Step 5: re-read inode data for all active vnodes.
573		 */
574		ip = VTOI(vp);
575		error =
576		    bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
577		    (int)fs->s_blocksize, NOCRED, &bp);
578		if (error) {
579			VOP_UNLOCK(vp, 0);
580			vrele(vp);
581			MNT_VNODE_FOREACH_ABORT(mp, mvp);
582			return (error);
583		}
584		ext2_ei2i((struct ext2_inode *) ((char *)bp->b_data +
585		    EXT2_INODE_SIZE(fs) * ino_to_fsbo(fs, ip->i_number)), ip);
586		brelse(bp);
587		VOP_UNLOCK(vp, 0);
588		vrele(vp);
589		MNT_ILOCK(mp);
590	}
591	MNT_IUNLOCK(mp);
592	return (0);
593}
594
595/*
596 * Common code for mount and mountroot
597 */
598static int
599ext2_mountfs(devvp, mp)
600	struct vnode *devvp;
601	struct mount *mp;
602{
603	struct ext2mount *ump;
604	struct buf *bp;
605	struct ext2_sb_info *fs;
606	struct ext2_super_block * es;
607	struct cdev *dev = devvp->v_rdev;
608	struct g_consumer *cp;
609	struct bufobj *bo;
610	int error;
611	int ronly;
612
613	ronly = vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0);
614	/* XXX: use VOP_ACESS to check FS perms */
615	DROP_GIANT();
616	g_topology_lock();
617	error = g_vfs_open(devvp, &cp, "ext2fs", ronly ? 0 : 1);
618	g_topology_unlock();
619	PICKUP_GIANT();
620	VOP_UNLOCK(devvp, 0);
621	if (error)
622		return (error);
623
624	/* XXX: should we check for some sectorsize or 512 instead? */
625	if (((SBSIZE % cp->provider->sectorsize) != 0) ||
626	    (SBSIZE < cp->provider->sectorsize)) {
627		DROP_GIANT();
628		g_topology_lock();
629		g_vfs_close(cp);
630		g_topology_unlock();
631		PICKUP_GIANT();
632		return (EINVAL);
633	}
634
635	bo = &devvp->v_bufobj;
636	bo->bo_private = cp;
637	bo->bo_ops = g_vfs_bufops;
638	if (devvp->v_rdev->si_iosize_max != 0)
639		mp->mnt_iosize_max = devvp->v_rdev->si_iosize_max;
640	if (mp->mnt_iosize_max > MAXPHYS)
641		mp->mnt_iosize_max = MAXPHYS;
642
643	bp = NULL;
644	ump = NULL;
645	if ((error = bread(devvp, SBLOCK, SBSIZE, NOCRED, &bp)) != 0)
646		goto out;
647	es = (struct ext2_super_block *)bp->b_data;
648	if (ext2_check_sb_compat(es, dev, ronly) != 0) {
649		error = EINVAL;		/* XXX needs translation */
650		goto out;
651	}
652	if ((es->s_state & EXT2_VALID_FS) == 0 ||
653	    (es->s_state & EXT2_ERROR_FS)) {
654		if (ronly || (mp->mnt_flag & MNT_FORCE)) {
655			printf(
656"WARNING: Filesystem was not properly dismounted\n");
657		} else {
658			printf(
659"WARNING: R/W mount denied.  Filesystem is not clean - run fsck\n");
660			error = EPERM;
661			goto out;
662		}
663	}
664	ump = bsd_malloc(sizeof *ump, M_EXT2MNT, M_WAITOK);
665	bzero((caddr_t)ump, sizeof *ump);
666	/* I don't know whether this is the right strategy. Note that
667	   we dynamically allocate both an ext2_sb_info and an ext2_super_block
668	   while Linux keeps the super block in a locked buffer
669	 */
670	ump->um_e2fs = bsd_malloc(sizeof(struct ext2_sb_info),
671		M_EXT2MNT, M_WAITOK);
672	ump->um_e2fs->s_es = bsd_malloc(sizeof(struct ext2_super_block),
673		M_EXT2MNT, M_WAITOK);
674	bcopy(es, ump->um_e2fs->s_es, (u_int)sizeof(struct ext2_super_block));
675	if ((error = compute_sb_data(devvp, ump->um_e2fs->s_es, ump->um_e2fs)))
676		goto out;
677	/*
678	 * We don't free the group descriptors allocated by compute_sb_data()
679	 * until ext2_unmount().  This is OK since the mount will succeed.
680	 */
681	brelse(bp);
682	bp = NULL;
683	fs = ump->um_e2fs;
684	fs->s_rd_only = ronly;	/* ronly is set according to mnt_flags */
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->s_wasvalid = fs->s_es->s_state & EXT2_VALID_FS ? 1 : 0;
689	if (ronly == 0) {
690		fs->s_dirt = 1;		/* mark it modified */
691		fs->s_es->s_state &= ~EXT2_VALID_FS;	/* 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	/* setting those two parameters allowed us to use
706	   ufs_bmap w/o changse !
707	*/
708	ump->um_nindir = EXT2_ADDR_PER_BLOCK(fs);
709	ump->um_bptrtodb = fs->s_es->s_log_block_size + 1;
710	ump->um_seqinc = EXT2_FRAGS_PER_BLOCK(fs);
711	if (ronly == 0)
712		ext2_sbupdate(ump, MNT_WAIT);
713	return (0);
714out:
715	if (bp)
716		brelse(bp);
717	if (cp != NULL) {
718		DROP_GIANT();
719		g_topology_lock();
720		g_vfs_close(cp);
721		g_topology_unlock();
722		PICKUP_GIANT();
723	}
724	if (ump) {
725		bsd_free(ump->um_e2fs->s_es, M_EXT2MNT);
726		bsd_free(ump->um_e2fs, M_EXT2MNT);
727		bsd_free(ump, M_EXT2MNT);
728		mp->mnt_data = NULL;
729	}
730	return (error);
731}
732
733/*
734 * unmount system call
735 */
736static int
737ext2_unmount(mp, mntflags, td)
738	struct mount *mp;
739	int mntflags;
740	struct thread *td;
741{
742	struct ext2mount *ump;
743	struct ext2_sb_info *fs;
744	int error, flags, ronly, i;
745
746	flags = 0;
747	if (mntflags & MNT_FORCE) {
748		if (mp->mnt_flag & MNT_ROOTFS)
749			return (EINVAL);
750		flags |= FORCECLOSE;
751	}
752	if ((error = ext2_flushfiles(mp, flags, td)) != 0)
753		return (error);
754	ump = VFSTOEXT2(mp);
755	fs = ump->um_e2fs;
756	ronly = fs->s_rd_only;
757	if (ronly == 0) {
758		if (fs->s_wasvalid)
759			fs->s_es->s_state |= EXT2_VALID_FS;
760		ext2_sbupdate(ump, MNT_WAIT);
761	}
762
763	/* release buffers containing group descriptors */
764	for(i = 0; i < fs->s_db_per_group; i++)
765		ULCK_BUF(fs->s_group_desc[i])
766	bsd_free(fs->s_group_desc, M_EXT2MNT);
767
768	/* release cached inode/block bitmaps */
769        for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
770                if (fs->s_inode_bitmap[i])
771			ULCK_BUF(fs->s_inode_bitmap[i])
772
773        for (i = 0; i < EXT2_MAX_GROUP_LOADED; i++)
774                if (fs->s_block_bitmap[i])
775			ULCK_BUF(fs->s_block_bitmap[i])
776
777	DROP_GIANT();
778	g_topology_lock();
779	g_vfs_close(ump->um_cp);
780	g_topology_unlock();
781	PICKUP_GIANT();
782	vrele(ump->um_devvp);
783	bsd_free(fs->s_es, M_EXT2MNT);
784	bsd_free(fs, M_EXT2MNT);
785	bsd_free(ump, M_EXT2MNT);
786	mp->mnt_data = NULL;
787	MNT_ILOCK(mp);
788	mp->mnt_flag &= ~MNT_LOCAL;
789	MNT_IUNLOCK(mp);
790	return (error);
791}
792
793/*
794 * Flush out all the files in a filesystem.
795 */
796static int
797ext2_flushfiles(mp, flags, td)
798	struct mount *mp;
799	int flags;
800	struct thread *td;
801{
802	int error;
803
804	error = vflush(mp, 0, flags, td);
805	return (error);
806}
807
808/*
809 * Get file system statistics.
810 * taken from ext2/super.c ext2_statfs
811 */
812static int
813ext2_statfs(mp, sbp, td)
814	struct mount *mp;
815	struct statfs *sbp;
816	struct thread *td;
817{
818        unsigned long overhead;
819	struct ext2mount *ump;
820	struct ext2_sb_info *fs;
821	struct ext2_super_block *es;
822	int i, nsb;
823
824	ump = VFSTOEXT2(mp);
825	fs = ump->um_e2fs;
826	es = fs->s_es;
827
828	if (es->s_magic != EXT2_SUPER_MAGIC)
829		panic("ext2_statfs - magic number spoiled");
830
831	/*
832	 * Compute the overhead (FS structures)
833	 */
834	if (es->s_feature_ro_compat & EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER) {
835		nsb = 0;
836		for (i = 0 ; i < fs->s_groups_count; i++)
837			if (ext2_group_sparse(i))
838				nsb++;
839	} else
840		nsb = fs->s_groups_count;
841	overhead = es->s_first_data_block +
842	    /* Superblocks and block group descriptors: */
843	    nsb * (1 + fs->s_db_per_group) +
844	    /* Inode bitmap, block bitmap, and inode table: */
845	    fs->s_groups_count * (1 + 1 + fs->s_itb_per_group);
846
847	sbp->f_bsize = EXT2_FRAG_SIZE(fs);
848	sbp->f_iosize = EXT2_BLOCK_SIZE(fs);
849	sbp->f_blocks = es->s_blocks_count - overhead;
850	sbp->f_bfree = es->s_free_blocks_count;
851	sbp->f_bavail = sbp->f_bfree - es->s_r_blocks_count;
852	sbp->f_files = es->s_inodes_count;
853	sbp->f_ffree = es->s_free_inodes_count;
854	return (0);
855}
856
857/*
858 * Go through the disk queues to initiate sandbagged IO;
859 * go through the inodes to write those that have been modified;
860 * initiate the writing of the super block if it has been modified.
861 *
862 * Note: we are always called with the filesystem marked `MPBUSY'.
863 */
864static int
865ext2_sync(mp, waitfor, td)
866	struct mount *mp;
867	int waitfor;
868	struct thread *td;
869{
870	struct vnode *mvp, *vp;
871	struct inode *ip;
872	struct ext2mount *ump = VFSTOEXT2(mp);
873	struct ext2_sb_info *fs;
874	int error, allerror = 0;
875
876	fs = ump->um_e2fs;
877	if (fs->s_dirt != 0 && fs->s_rd_only != 0) {		/* XXX */
878		printf("fs = %s\n", fs->fs_fsmnt);
879		panic("ext2_sync: rofs mod");
880	}
881	/*
882	 * Write back each (modified) inode.
883	 */
884	MNT_ILOCK(mp);
885loop:
886	MNT_VNODE_FOREACH(vp, mp, mvp) {
887		VI_LOCK(vp);
888		if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) {
889			VI_UNLOCK(vp);
890			continue;
891		}
892		MNT_IUNLOCK(mp);
893		ip = VTOI(vp);
894		if ((ip->i_flag &
895		    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
896		    (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
897		    waitfor == MNT_LAZY)) {
898			VI_UNLOCK(vp);
899			MNT_ILOCK(mp);
900			continue;
901		}
902		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
903		if (error) {
904			MNT_ILOCK(mp);
905			if (error == ENOENT) {
906				MNT_VNODE_FOREACH_ABORT_ILOCKED(mp, mvp);
907				goto loop;
908			}
909			continue;
910		}
911		if ((error = VOP_FSYNC(vp, waitfor, td)) != 0)
912			allerror = error;
913		VOP_UNLOCK(vp, 0);
914		vrele(vp);
915		MNT_ILOCK(mp);
916	}
917	MNT_IUNLOCK(mp);
918	/*
919	 * Force stale file system control information to be flushed.
920	 */
921	if (waitfor != MNT_LAZY) {
922		vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
923		if ((error = VOP_FSYNC(ump->um_devvp, waitfor, td)) != 0)
924			allerror = error;
925		VOP_UNLOCK(ump->um_devvp, 0);
926	}
927	/*
928	 * Write back modified superblock.
929	 */
930	if (fs->s_dirt != 0) {
931		fs->s_dirt = 0;
932		fs->s_es->s_wtime = time_second;
933		if ((error = ext2_sbupdate(ump, waitfor)) != 0)
934			allerror = error;
935	}
936	return (allerror);
937}
938
939/*
940 * Look up an EXT2FS dinode number to find its incore vnode, otherwise read it
941 * in from disk.  If it is in core, wait for the lock bit to clear, then
942 * return the inode locked.  Detection and handling of mount points must be
943 * done by the calling routine.
944 */
945static int
946ext2_vget(mp, ino, flags, vpp)
947	struct mount *mp;
948	ino_t ino;
949	int flags;
950	struct vnode **vpp;
951{
952	struct ext2_sb_info *fs;
953	struct inode *ip;
954	struct ext2mount *ump;
955	struct buf *bp;
956	struct vnode *vp;
957	struct cdev *dev;
958	int i, error;
959	int used_blocks;
960	struct thread *td;
961
962	td = curthread;
963	error = vfs_hash_get(mp, ino, flags, td, vpp, NULL, NULL);
964	if (error || *vpp != NULL)
965		return (error);
966
967	ump = VFSTOEXT2(mp);
968	dev = ump->um_dev;
969
970	/*
971	 * If this malloc() is performed after the getnewvnode()
972	 * it might block, leaving a vnode with a NULL v_data to be
973	 * found by ext2_sync() if a sync happens to fire right then,
974	 * which will cause a panic because ext2_sync() blindly
975	 * dereferences vp->v_data (as well it should).
976	 */
977	ip = malloc(sizeof(struct inode), M_EXT2NODE, M_WAITOK | M_ZERO);
978
979	/* Allocate a new vnode/inode. */
980	if ((error = getnewvnode("ext2fs", mp, &ext2_vnodeops, &vp)) != 0) {
981		*vpp = NULL;
982		free(ip, M_EXT2NODE);
983		return (error);
984	}
985	vp->v_data = ip;
986	ip->i_vnode = vp;
987	ip->i_e2fs = fs = ump->um_e2fs;
988	ip->i_number = ino;
989
990	lockmgr(vp->v_vnlock, LK_EXCLUSIVE, NULL);
991	error = insmntque(vp, mp);
992	if (error != 0) {
993		free(ip, M_EXT2NODE);
994		*vpp = NULL;
995		return (error);
996	}
997	error = vfs_hash_insert(vp, ino, flags, td, vpp, NULL, NULL);
998	if (error || *vpp != NULL)
999		return (error);
1000
1001	/* Read in the disk contents for the inode, copy into the inode. */
1002#if 0
1003printf("ext2_vget(%d) dbn= %lu ", ino, fsbtodb(fs, ino_to_fsba(fs, ino)));
1004#endif
1005	if ((error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
1006	    (int)fs->s_blocksize, NOCRED, &bp)) != 0) {
1007		/*
1008		 * The inode does not contain anything useful, so it would
1009		 * be misleading to leave it on its hash chain. With mode
1010		 * still zero, it will be unlinked and returned to the free
1011		 * list by vput().
1012		 */
1013		vput(vp);
1014		brelse(bp);
1015		*vpp = NULL;
1016		return (error);
1017	}
1018	/* convert ext2 inode to dinode */
1019	ext2_ei2i((struct ext2_inode *) ((char *)bp->b_data + EXT2_INODE_SIZE(fs) *
1020			ino_to_fsbo(fs, ino)), ip);
1021	ip->i_block_group = ino_to_cg(fs, ino);
1022	ip->i_next_alloc_block = 0;
1023	ip->i_next_alloc_goal = 0;
1024	ip->i_prealloc_count = 0;
1025	ip->i_prealloc_block = 0;
1026        /* now we want to make sure that block pointers for unused
1027           blocks are zeroed out - ext2_balloc depends on this
1028	   although for regular files and directories only
1029	*/
1030	if(S_ISDIR(ip->i_mode) || S_ISREG(ip->i_mode)) {
1031		used_blocks = (ip->i_size+fs->s_blocksize-1) / fs->s_blocksize;
1032		for(i = used_blocks; i < EXT2_NDIR_BLOCKS; i++)
1033			ip->i_db[i] = 0;
1034	}
1035/*
1036	ext2_print_inode(ip);
1037*/
1038	brelse(bp);
1039
1040	/*
1041	 * Initialize the vnode from the inode, check for aliases.
1042	 * Note that the underlying vnode may have changed.
1043	 */
1044	if ((error = ext2_vinit(mp, &ext2_fifoops, &vp)) != 0) {
1045		vput(vp);
1046		*vpp = NULL;
1047		return (error);
1048	}
1049	/*
1050	 * Finish inode initialization now that aliasing has been resolved.
1051	 */
1052	ip->i_devvp = ump->um_devvp;
1053	/*
1054	 * Set up a generation number for this inode if it does not
1055	 * already have one. This should only happen on old filesystems.
1056	 */
1057	if (ip->i_gen == 0) {
1058		ip->i_gen = random() / 2 + 1;
1059		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
1060			ip->i_flag |= IN_MODIFIED;
1061	}
1062	*vpp = vp;
1063	return (0);
1064}
1065
1066/*
1067 * File handle to vnode
1068 *
1069 * Have to be really careful about stale file handles:
1070 * - check that the inode number is valid
1071 * - call ext2_vget() to get the locked inode
1072 * - check for an unallocated inode (i_mode == 0)
1073 * - check that the given client host has export rights and return
1074 *   those rights via. exflagsp and credanonp
1075 */
1076static int
1077ext2_fhtovp(mp, fhp, vpp)
1078	struct mount *mp;
1079	struct fid *fhp;
1080	struct vnode **vpp;
1081{
1082	struct inode *ip;
1083	struct ufid *ufhp;
1084	struct vnode *nvp;
1085	struct ext2_sb_info *fs;
1086	int error;
1087
1088	ufhp = (struct ufid *)fhp;
1089	fs = VFSTOEXT2(mp)->um_e2fs;
1090	if (ufhp->ufid_ino < ROOTINO ||
1091	    ufhp->ufid_ino > fs->s_groups_count * fs->s_es->s_inodes_per_group)
1092		return (ESTALE);
1093
1094	error = VFS_VGET(mp, ufhp->ufid_ino, LK_EXCLUSIVE, &nvp);
1095	if (error) {
1096		*vpp = NULLVP;
1097		return (error);
1098	}
1099	ip = VTOI(nvp);
1100	if (ip->i_mode == 0 ||
1101	    ip->i_gen != ufhp->ufid_gen || ip->i_nlink <= 0) {
1102		vput(nvp);
1103		*vpp = NULLVP;
1104		return (ESTALE);
1105	}
1106	*vpp = nvp;
1107	vnode_create_vobject(*vpp, 0, curthread);
1108	return (0);
1109}
1110
1111/*
1112 * Write a superblock and associated information back to disk.
1113 */
1114static int
1115ext2_sbupdate(mp, waitfor)
1116	struct ext2mount *mp;
1117	int waitfor;
1118{
1119	struct ext2_sb_info *fs = mp->um_e2fs;
1120	struct ext2_super_block *es = fs->s_es;
1121	struct buf *bp;
1122	int error = 0;
1123/*
1124printf("\nupdating superblock, waitfor=%s\n", waitfor == MNT_WAIT ? "yes":"no");
1125*/
1126	bp = getblk(mp->um_devvp, SBLOCK, SBSIZE, 0, 0, 0);
1127	bcopy((caddr_t)es, bp->b_data, (u_int)sizeof(struct ext2_super_block));
1128	if (waitfor == MNT_WAIT)
1129		error = bwrite(bp);
1130	else
1131		bawrite(bp);
1132
1133	/*
1134	 * The buffers for group descriptors, inode bitmaps and block bitmaps
1135	 * are not busy at this point and are (hopefully) written by the
1136	 * usual sync mechanism. No need to write them here
1137		 */
1138
1139	return (error);
1140}
1141
1142/*
1143 * Return the root of a filesystem.
1144 */
1145static int
1146ext2_root(mp, flags, vpp, td)
1147	struct mount *mp;
1148	int flags;
1149	struct vnode **vpp;
1150	struct thread *td;
1151{
1152	struct vnode *nvp;
1153	int error;
1154
1155	error = VFS_VGET(mp, (ino_t)ROOTINO, LK_EXCLUSIVE, &nvp);
1156	if (error)
1157		return (error);
1158	*vpp = nvp;
1159	return (0);
1160}
1161