path: root/sys/ufs/ffs/ffs_vfsops.c

/*	$OpenBSD: ffs_vfsops.c,v 1.48 2001/12/19 08:58:07 art Exp $	*/
/*	$NetBSD: ffs_vfsops.c,v 1.19 1996/02/09 22:22:26 christos Exp $	*/

/*
 * Copyright (c) 1989, 1991, 1993, 1994
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)ffs_vfsops.c	8.14 (Berkeley) 11/28/94
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/socket.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/file.h>
#include <sys/disklabel.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <sys/pool.h>

#include <dev/rndvar.h>

#include <miscfs/specfs/specdev.h>

#include <ufs/ufs/quota.h>
#include <ufs/ufs/ufsmount.h>
#include <ufs/ufs/inode.h>
#include <ufs/ufs/dir.h>
#include <ufs/ufs/ufs_extern.h>

#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>

int ffs_sbupdate __P((struct ufsmount *, int));
int ffs_reload_vnode(struct vnode *, void *);
int ffs_sync_vnode(struct vnode *, void *);

struct vfsops ffs_vfsops = {
	ffs_mount,
	ufs_start,
	ffs_unmount,
	ufs_root,
	ufs_quotactl,
	ffs_statfs,
	ffs_sync,
	ffs_vget,
	ffs_fhtovp,
	ffs_vptofh,
	ffs_init,
	ffs_sysctl,
	ufs_check_export
};

struct inode_vtbl ffs_vtbl = {
	ffs_truncate,
	ffs_update,
	ffs_inode_alloc,
	ffs_inode_free,
	ffs_balloc,
	ffs_bufatoff
};

extern u_long nextgennumber;

/*
 * Called by main() when ufs is going to be mounted as root.
 */

struct pool ffs_ino_pool;

int
ffs_mountroot()
{
	extern struct vnode *rootvp;
	struct fs *fs;
	struct mount *mp;
	struct proc *p = curproc;	/* XXX */
	struct ufsmount *ump;
	int error;

	/*
	 * Get vnodes for swapdev and rootdev.
	 */
	if ((error = bdevvp(swapdev, &swapdev_vp)) ||
	    (error = bdevvp(rootdev, &rootvp))) {
		printf("ffs_mountroot: can't setup bdevvp's");
		return (error);
	}

	if ((error = vfs_rootmountalloc("ffs", "root_device", &mp)) != 0)
		return (error);
	if ((error = ffs_mountfs(rootvp, mp, p)) != 0) {
		mp->mnt_vfc->vfc_refcount--;
		vfs_unbusy(mp, p);
		free(mp, M_MOUNT);
		return (error);
	}
	simple_lock(&mountlist_slock);
	CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
	simple_unlock(&mountlist_slock);
	ump = VFSTOUFS(mp);
	fs = ump->um_fs;
	(void) copystr(mp->mnt_stat.f_mntonname, fs->fs_fsmnt, MNAMELEN - 1, 0);
	(void)ffs_statfs(mp, &mp->mnt_stat, p);
	vfs_unbusy(mp, p);
	inittodr(fs->fs_time);
	return (0);
}

/*
 * VFS Operations.
 *
 * mount system call
 */
int
ffs_mount(mp, path, data, ndp, p)
	register struct mount *mp;
	const char *path;
	void *data;
	struct nameidata *ndp;
	struct proc *p;
{
	struct vnode *devvp;
	struct ufs_args args;
	struct ufsmount *ump = NULL;
	register struct fs *fs;
	int error = 0, flags;
	int ronly;
	mode_t accessmode;
	size_t size;

	error = copyin(data, &args, sizeof (struct ufs_args));
	if (error)
		return (error);

#ifndef FFS_SOFTUPDATES
	if (mp->mnt_flag & MNT_SOFTDEP) {
		printf("WARNING: soft updates isn't compiled in\n");
		mp->mnt_flag &= ~MNT_SOFTDEP;
	}
#endif

	/*
	 * Soft updates is incompatible with "async",
	 * so if we are doing softupdates stop the user
	 * from setting the async flag.
	 */
	if ((mp->mnt_flag & (MNT_SOFTDEP | MNT_ASYNC)) ==
	    (MNT_SOFTDEP | MNT_ASYNC)) {
		return (EINVAL);
	}
	/*
	 * If updating, check whether changing from read-only to
	 * read/write; if there is no device name, that's all we do.
	 */
	if (mp->mnt_flag & MNT_UPDATE) {
		ump = VFSTOUFS(mp);
		fs = ump->um_fs;
		devvp = ump->um_devvp;
		error = 0;
		ronly = fs->fs_ronly;

		if (ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
			flags = WRITECLOSE;
			if (mp->mnt_flag & MNT_FORCE)
				flags |= FORCECLOSE;
			if (fs->fs_flags & FS_DOSOFTDEP) {
				error = softdep_flushfiles(mp, flags, p);
				mp->mnt_flag &= ~MNT_SOFTDEP;
			} else
				error = ffs_flushfiles(mp, flags, p);
			ronly = 1;
		}

		/*
		 * Flush soft dependencies if disabling it via an update
		 * mount. This may leave some items to be processed,
		 * so don't do this yet XXX.
		 */
		if ((fs->fs_flags & FS_DOSOFTDEP) &&
		    !(mp->mnt_flag & MNT_SOFTDEP) &&
		    !(mp->mnt_flag & MNT_RDONLY) && fs->fs_ronly == 0) {
#if 0
			flags = WRITECLOSE;
			if (mp->mnt_flag & MNT_FORCE)
				flags |= FORCECLOSE;
			error = softdep_flushfiles(mp, flags, p);
#elif FFS_SOFTUPDATES
			mp->mnt_flag |= MNT_SOFTDEP;
#endif
		}
		/*
		 * When upgrading to a softdep mount, we must first flush
		 * all vnodes. (not done yet -- see above)
		 */
		if (!(fs->fs_flags & FS_DOSOFTDEP) &&
		    (mp->mnt_flag & MNT_SOFTDEP) && fs->fs_ronly == 0) {
#if 0
			flags = WRITECLOSE;
			if (mp->mnt_flag & MNT_FORCE)
				flags |= FORCECLOSE;
			error = ffs_flushfiles(mp, flags, p);
#else
			mp->mnt_flag &= ~MNT_SOFTDEP;
#endif
		}

		if (!error && (mp->mnt_flag & MNT_RELOAD))
			error = ffs_reload(mp, ndp->ni_cnd.cn_cred, p);
		if (error)
			goto error_1;

		if (ronly && (mp->mnt_flag & MNT_WANTRDWR)) {
			/*
			 * If upgrade to read-write by non-root, then verify
			 * that user has necessary permissions on the device.
			 */
			if (p->p_ucred->cr_uid != 0) {
				vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
				error = VOP_ACCESS(devvp, VREAD | VWRITE,
						   p->p_ucred, p);
				VOP_UNLOCK(devvp, 0, p);
				if (error)
					goto error_1;
			}

			if (fs->fs_clean == 0) {
#if 0
				/*
				 * It is safe mount unclean file system
				 * if it was previously mounted with softdep
				 * but we may loss space and must
				 * sometimes run fsck manually.
				 */
				if (fs->fs_flags & FS_DOSOFTDEP)
					printf(
"WARNING: %s was not properly unmounted\n",
					    fs->fs_fsmnt);
				else
#endif
				if (mp->mnt_flag & MNT_FORCE) {
					printf(
"WARNING: %s was not properly unmounted\n",
					    fs->fs_fsmnt);
				} else {
					printf(
"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
					    fs->fs_fsmnt);
					error = EPERM;
					goto error_1;
				}
			}

			if ((fs->fs_flags & FS_DOSOFTDEP)) {
				error = softdep_mount(devvp, mp, fs,
						      p->p_ucred);
				if (error)
					goto error_1;
			}
			fs->fs_contigdirs=(u_int8_t*)malloc((u_long)fs->fs_ncg,
							    M_UFSMNT, M_WAITOK);
			bzero(fs->fs_contigdirs, fs->fs_ncg);

			ronly = 0;
		}
		if (args.fspec == 0) {
			/*
			 * Process export requests.
			 */
			error = vfs_export(mp, &ump->um_export, &args.export);
			if (error)
				goto error_1;
			else
				goto success;
		}
	}
	/*
	 * Not an update, or updating the name: look up the name
	 * and verify that it refers to a sensible block device.
	 */
	NDINIT(ndp, LOOKUP, FOLLOW, UIO_USERSPACE, args.fspec, p);
	if ((error = namei(ndp)) != 0)
		goto error_1;

	devvp = ndp->ni_vp;

	if (devvp->v_type != VBLK) {
		error = ENOTBLK;
		goto error_2;
	}

	if (major(devvp->v_rdev) >= nblkdev) {
		error = ENXIO;
		goto error_2;
	}

	/*
	 * If mount by non-root, then verify that user has necessary
	 * permissions on the device.
	 */
	if (p->p_ucred->cr_uid != 0) {
		accessmode = VREAD;
		if ((mp->mnt_flag & MNT_RDONLY) == 0)
			accessmode |= VWRITE;
		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
		error = VOP_ACCESS(devvp, accessmode, p->p_ucred, p);
		VOP_UNLOCK(devvp, 0, p);
		if (error)
			goto error_2;
	}

	if (mp->mnt_flag & MNT_UPDATE) {
		/*
		 * UPDATE
		 * If it's not the same vnode, or at least the same device
		 * then it's not correct.
		 */

		if (devvp != ump->um_devvp) {
			if (devvp->v_rdev == ump->um_devvp->v_rdev) {
				vrele(devvp);
			} else {
				error = EINVAL;	/* needs translation */
			}
		} else
			vrele(devvp);
		/*
		 * Update device name only on success
		 */
		if (!error) {
			/*
			 * Save "mounted from" info for mount point (NULL pad)
			 */
			copyinstr(args.fspec,
				  mp->mnt_stat.f_mntfromname,
				  MNAMELEN - 1,
				  &size);
			bzero(mp->mnt_stat.f_mntfromname + size,
			      MNAMELEN - size);
		}
	} else {
		/*
		 * Since this is a new mount, we want the names for
		 * the device and the mount point copied in.  If an
		 * error occurs,  the mountpoint is discarded by the
		 * upper level code.
		 */
		/* Save "last mounted on" info for mount point (NULL pad)*/
		copyinstr(path,				/* mount point*/
			  mp->mnt_stat.f_mntonname,	/* save area*/
			  MNAMELEN - 1,			/* max size*/
			  &size);			/* real size*/
		bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);

		/* Save "mounted from" info for mount point (NULL pad)*/
		copyinstr(args.fspec,			/* device name*/
			  mp->mnt_stat.f_mntfromname,	/* save area*/
			  MNAMELEN - 1,			/* max size*/
			  &size);			/* real size*/
		bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);

		error = ffs_mountfs(devvp, mp, p);
	}

	if (error)
		goto error_2;

	/*
	 * Initialize FS stat information in mount struct; uses both
	 * mp->mnt_stat.f_mntonname and mp->mnt_stat.f_mntfromname
	 *
	 * This code is common to root and non-root mounts
	 */
	bcopy(&args, &mp->mnt_stat.mount_info.ufs_args, sizeof(args));
	(void)VFS_STATFS(mp, &mp->mnt_stat, p);

success:
	if (path && (mp->mnt_flag & MNT_UPDATE)) {
		/* Update clean flag after changing read-onlyness. */
		fs = ump->um_fs;
		if (ronly != fs->fs_ronly) {
			fs->fs_ronly = ronly;
			fs->fs_clean = ronly &&
			    (fs->fs_flags & FS_UNCLEAN) == 0 ? 1 : 0;
			if (ronly)
				free(fs->fs_contigdirs, M_UFSMNT);
		}
		if (!ronly) {
			if (mp->mnt_flag & MNT_SOFTDEP)
				fs->fs_flags |= FS_DOSOFTDEP;
			else
				fs->fs_flags &= ~FS_DOSOFTDEP;
		}
		ffs_sbupdate(ump, MNT_WAIT);
	}
	return (0);

error_2:	/* error with devvp held */
	vrele (devvp);
error_1:	/* no state to back out */
	return (error);
}


struct ffs_reload_args {
	struct fs *fs;
	struct proc *p;
	struct ucred *cred;
	struct vnode *devvp;
};

int
ffs_reload_vnode(struct vnode *vp, void *args) 
{
	struct ffs_reload_args *fra = args;
	struct inode *ip;
	struct buf *bp;
	int error;

	/*
	 * Step 4: invalidate all inactive vnodes.
	 */
	if (vp->v_usecount == 0) {
		vgonel(vp, fra->p);
		return (0);
	}

	/*
	 * Step 5: invalidate all cached file data.
	 */
	if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, fra->p))
		return (0);

	if (vinvalbuf(vp, 0, fra->cred, fra->p, 0, 0))
		panic("ffs_reload: dirty2");
	/*
	 * Step 6: re-read inode data for all active vnodes.
	 */
	ip = VTOI(vp);
	error = bread(fra->devvp, 
	    fsbtodb(fra->fs, ino_to_fsba(fra->fs, ip->i_number)),
	    (int)fra->fs->fs_bsize, NOCRED, &bp);
	if (error) {
		vput(vp);
		return (error);
	}
	ip->i_din.ffs_din = *((struct dinode *)bp->b_data +
	    ino_to_fsbo(fra->fs, ip->i_number));
	ip->i_effnlink = ip->i_ffs_nlink;
	brelse(bp);
	vput(vp);
	return (0);
}

/*
 * Reload all incore data for a filesystem (used after running fsck on
 * the root filesystem and finding things to fix). The filesystem must
 * be mounted read-only.
 *
 * Things to do to update the mount:
 *	1) invalidate all cached meta-data.
 *	2) re-read superblock from disk.
 *	3) re-read summary information from disk.
 *	4) invalidate all inactive vnodes.
 *	5) invalidate all cached file data.
 *	6) re-read inode data for all active vnodes.
 */
int
ffs_reload(mountp, cred, p)
	register struct mount *mountp;
	struct ucred *cred;
	struct proc *p;
{
	struct vnode *devvp;
	caddr_t space;
	struct fs *fs, *newfs;
	struct partinfo dpart;
	int i, blks, size, error;
	int32_t *lp;
	struct buf *bp = NULL;
	struct ffs_reload_args fra;

	if ((mountp->mnt_flag & MNT_RDONLY) == 0)
		return (EINVAL);
	/*
	 * Step 1: invalidate all cached meta-data.
	 */
	devvp = VFSTOUFS(mountp)->um_devvp;
	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
	error = vinvalbuf(devvp, 0, cred, p, 0, 0);
	VOP_UNLOCK(devvp, 0, p);
	if (error)
		panic("ffs_reload: dirty1");

	/*
	 * Step 2: re-read superblock from disk.
	 */
	if (VOP_IOCTL(devvp, DIOCGPART, (caddr_t)&dpart, FREAD, NOCRED, p) != 0)
		size = DEV_BSIZE;
	else
		size = dpart.disklab->d_secsize;
	error = bread(devvp, (daddr_t)(SBOFF / size), SBSIZE, NOCRED, &bp);
	if (error)
		return (error);
	newfs = (struct fs *)bp->b_data;
	if (newfs->fs_magic != FS_MAGIC || newfs->fs_bsize > MAXBSIZE ||
	    newfs->fs_bsize < sizeof(struct fs)) {
		brelse(bp);
		return (EIO);		/* XXX needs translation */
	}
	fs = VFSTOUFS(mountp)->um_fs;
	/*
	 * Copy pointer fields back into superblock before copying in	XXX
	 * new superblock. These should really be in the ufsmount.	XXX
	 * Note that important parameters (eg fs_ncg) are unchanged.
	 */
	newfs->fs_csp = fs->fs_csp;
	newfs->fs_maxcluster = fs->fs_maxcluster;
	newfs->fs_ronly = fs->fs_ronly;
	bcopy(newfs, fs, (u_int)fs->fs_sbsize);
	if (fs->fs_sbsize < SBSIZE)
		bp->b_flags |= B_INVAL;
	brelse(bp);
	mountp->mnt_maxsymlinklen = fs->fs_maxsymlinklen;
	ffs_oldfscompat(fs);
	(void)ffs_statfs(mountp, &mountp->mnt_stat, p);
	/*
	 * Step 3: re-read summary information from disk.
	 */
	blks = howmany(fs->fs_cssize, fs->fs_fsize);
	space = (caddr_t)fs->fs_csp;
	for (i = 0; i < blks; i += fs->fs_frag) {
		size = fs->fs_bsize;
		if (i + fs->fs_frag > blks)
			size = (blks - i) * fs->fs_fsize;
		error = bread(devvp, fsbtodb(fs, fs->fs_csaddr + i), size,
			      NOCRED, &bp);
		if (error)
			return (error);
		bcopy(bp->b_data, space, (u_int)size);
		space += size;
		brelse(bp);
	}
	if ((fs->fs_flags & FS_DOSOFTDEP))
		(void) softdep_mount(devvp, mountp, fs, cred);
	/*
	 * We no longer know anything about clusters per cylinder group.
	 */
	if (fs->fs_contigsumsize > 0) {
		lp = fs->fs_maxcluster;
		for (i = 0; i < fs->fs_ncg; i++)
			*lp++ = fs->fs_contigsumsize;
	}

	fra.p = p;
	fra.cred = cred;
	fra.fs = fs;
	fra.devvp = devvp;

	error = vfs_mount_foreach_vnode(mountp, ffs_reload_vnode, &fra);

	return (error);
}

/*
 * Common code for mount and mountroot
 */
int
ffs_mountfs(devvp, mp, p)
	register struct vnode *devvp;
	struct mount *mp;
	struct proc *p;
{
	register struct ufsmount *ump;
	struct buf *bp;
	register struct fs *fs;
	dev_t dev;
	struct partinfo dpart;
	caddr_t space;
	int error, i, blks, size, ronly;
	int32_t *lp;
	size_t strsize;
	struct ucred *cred;
	extern struct vnode *rootvp;
	u_int64_t maxfilesize;					/* XXX */

	dev = devvp->v_rdev;
	cred = p ? p->p_ucred : NOCRED;
	/*
	 * Disallow multiple mounts of the same device.
	 * Disallow mounting of a device that is currently in use
	 * (except for root, which might share swap device for miniroot).
	 * Flush out any old buffers remaining from a previous use.
	 */
	if ((error = vfs_mountedon(devvp)) != 0)
		return (error);
	if (vcount(devvp) > 1 && devvp != rootvp)
		return (EBUSY);
	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
	error = vinvalbuf(devvp, V_SAVE, cred, p, 0, 0);
	VOP_UNLOCK(devvp, 0, p);
	if (error)
		return (error);

	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
	error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p);
	if (error)
		return (error);
	if (VOP_IOCTL(devvp, DIOCGPART, (caddr_t)&dpart, FREAD, cred, p) != 0)
		size = DEV_BSIZE;
	else
		size = dpart.disklab->d_secsize;

	bp = NULL;
	ump = NULL;
	error = bread(devvp, (daddr_t)(SBOFF / size), SBSIZE, cred, &bp);
	if (error)
		goto out;
	fs = (struct fs *)bp->b_data;
	if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE ||
	    fs->fs_bsize < sizeof(struct fs)) {
		error = EFTYPE;		/* Inappropriate format */
		goto out;
	}
	fs->fs_fmod = 0;
	fs->fs_flags &= ~FS_UNCLEAN;
	if (fs->fs_clean == 0) {
		fs->fs_flags |= FS_UNCLEAN;
#if 0
		/*
		 * It is safe mount unclean file system
		 * if it was previously mounted with softdep
		 * but we may loss space and must
		 * sometimes run fsck manually.
		 */
		if (fs->fs_flags & FS_DOSOFTDEP)
			printf(
"WARNING: %s was not properly unmounted\n",
			    fs->fs_fsmnt);
		else
#endif
		if (ronly || (mp->mnt_flag & MNT_FORCE)) {
			printf(
"WARNING: %s was not properly unmounted\n",
			    fs->fs_fsmnt);
		} else {
			printf(
"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
			    fs->fs_fsmnt);
			error = EPERM;
			goto out;
		}
	}
	/* XXX updating 4.2 FFS superblocks trashes rotational layout tables */
	if (fs->fs_postblformat == FS_42POSTBLFMT && !ronly) {
		error = EROFS;		/* XXX what should be returned? */
		goto out;
	}
	ump = malloc(sizeof *ump, M_UFSMNT, M_WAITOK);
	bzero((caddr_t)ump, sizeof *ump);
	ump->um_fs = malloc((u_long)fs->fs_sbsize, M_UFSMNT,
	    M_WAITOK);
	bcopy(bp->b_data, ump->um_fs, (u_int)fs->fs_sbsize);
	if (fs->fs_sbsize < SBSIZE)
		bp->b_flags |= B_INVAL;
	brelse(bp);
	bp = NULL;
	fs = ump->um_fs;
	fs->fs_ronly = ronly;
	size = fs->fs_cssize;
	blks = howmany(size, fs->fs_fsize);
	if (fs->fs_contigsumsize > 0)
		size += fs->fs_ncg * sizeof(int32_t);
	space = malloc((u_long)size, M_UFSMNT, M_WAITOK);
	fs->fs_csp = (struct csum *)space;
	for (i = 0; i < blks; i += fs->fs_frag) {
		size = fs->fs_bsize;
		if (i + fs->fs_frag > blks)
			size = (blks - i) * fs->fs_fsize;
		error = bread(devvp, fsbtodb(fs, fs->fs_csaddr + i), size,
			      cred, &bp);
		if (error) {
			free(fs->fs_csp, M_UFSMNT);
			goto out;
		}
		bcopy(bp->b_data, space, (u_int)size);
		space += size;
		brelse(bp);
		bp = NULL;
	}
	if (fs->fs_contigsumsize > 0) {
		fs->fs_maxcluster = lp = (int32_t *)space;
		for (i = 0; i < fs->fs_ncg; i++)
			*lp++ = fs->fs_contigsumsize;
	}
	mp->mnt_data = (qaddr_t)ump;
	mp->mnt_stat.f_fsid.val[0] = (long)dev;
	/* Use on-disk fsid if it exists, else fake it */
	if (fs->fs_id[0] != 0 && fs->fs_id[1] != 0)
		mp->mnt_stat.f_fsid.val[1] = fs->fs_id[1];
	else
		mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
	mp->mnt_maxsymlinklen = fs->fs_maxsymlinklen;
	mp->mnt_flag |= MNT_LOCAL;
	ump->um_mountp = mp;
	ump->um_dev = dev;
	ump->um_devvp = devvp;
	ump->um_nindir = fs->fs_nindir;
	ump->um_bptrtodb = fs->fs_fsbtodb;
	ump->um_seqinc = fs->fs_frag;
	for (i = 0; i < MAXQUOTAS; i++)
		ump->um_quotas[i] = NULLVP;
	devvp->v_specmountpoint = mp;
	ffs_oldfscompat(fs);

	if (ronly)
		fs->fs_contigdirs = NULL;
	else {
		fs->fs_contigdirs = (u_int8_t*)malloc((u_long)fs->fs_ncg,
						      M_UFSMNT, M_WAITOK);
		bzero(fs->fs_contigdirs, fs->fs_ncg);
	}

	/*
	 * Set FS local "last mounted on" information (NULL pad)
	 */
	copystr(mp->mnt_stat.f_mntonname,	/* mount point*/
		fs->fs_fsmnt,			/* copy area*/
		sizeof(fs->fs_fsmnt) - 1,	/* max size*/
		&strsize);			/* real size*/
	bzero(fs->fs_fsmnt + strsize, sizeof(fs->fs_fsmnt) - strsize);

#if 0
	if( mp->mnt_flag & MNT_ROOTFS) {
		/*
		 * Root mount; update timestamp in mount structure.
		 * this will be used by the common root mount code
		 * to update the system clock.
		 */
		mp->mnt_time = fs->fs_time;
	}
#endif

	ump->um_savedmaxfilesize = fs->fs_maxfilesize;		/* XXX */
	maxfilesize = (u_int64_t)0x80000000 * fs->fs_bsize - 1;	/* XXX */
	if (fs->fs_maxfilesize > maxfilesize)			/* XXX */
		fs->fs_maxfilesize = maxfilesize;		/* XXX */
	if (ronly == 0) {
		if ((fs->fs_flags & FS_DOSOFTDEP) &&
		    (error = softdep_mount(devvp, mp, fs, cred)) != 0) {
			free(fs->fs_csp, M_UFSMNT);
			free(fs->fs_contigdirs, M_UFSMNT);
			goto out;
		}
		fs->fs_fmod = 1;
		fs->fs_clean = 0;
		if (mp->mnt_flag & MNT_SOFTDEP)
			fs->fs_flags |= FS_DOSOFTDEP;
		else
			fs->fs_flags &= ~FS_DOSOFTDEP;
		(void) ffs_sbupdate(ump, MNT_WAIT);
	}
	return (0);
out:
	devvp->v_specmountpoint = NULL;
	if (bp)
		brelse(bp);
	(void)VOP_CLOSE(devvp, ronly ? FREAD : FREAD|FWRITE, cred, p);
	if (ump) {
		free(ump->um_fs, M_UFSMNT);
		free(ump, M_UFSMNT);
		mp->mnt_data = (qaddr_t)0;
	}
	return (error);
}

/*
 * Sanity checks for old file systems.
 *
 * XXX - goes away some day.
 */
int
ffs_oldfscompat(fs)
	struct fs *fs;
{
	int i;

	fs->fs_npsect = max(fs->fs_npsect, fs->fs_nsect);	/* XXX */
	fs->fs_interleave = max(fs->fs_interleave, 1);		/* XXX */
	if (fs->fs_postblformat == FS_42POSTBLFMT)		/* XXX */
		fs->fs_nrpos = 8;				/* XXX */
	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
		u_int64_t sizepb = fs->fs_bsize;		/* XXX */
								/* XXX */
		fs->fs_maxfilesize = fs->fs_bsize * NDADDR - 1;	/* XXX */
		for (i = 0; i < NIADDR; i++) {			/* XXX */
			sizepb *= NINDIR(fs);			/* XXX */
			fs->fs_maxfilesize += sizepb;		/* XXX */
		}						/* XXX */
		fs->fs_qbmask = ~fs->fs_bmask;			/* XXX */
		fs->fs_qfmask = ~fs->fs_fmask;			/* XXX */
	}							/* XXX */
	if (fs->fs_avgfilesize <= 0)				/* XXX */
		fs->fs_avgfilesize = AVFILESIZ;			/* XXX */
	if (fs->fs_avgfpdir <= 0)				/* XXX */
		fs->fs_avgfpdir = AFPDIR;			/* XXX */
	return (0);
}

/*
 * unmount system call
 */
int
ffs_unmount(mp, mntflags, p)
	struct mount *mp;
	int mntflags;
	struct proc *p;
{
	register struct ufsmount *ump;
	register struct fs *fs;
	int error, flags;

	flags = 0;
	if (mntflags & MNT_FORCE)
		flags |= FORCECLOSE;

	ump = VFSTOUFS(mp);
	fs = ump->um_fs;
	if (mp->mnt_flag & MNT_SOFTDEP)
		error = softdep_flushfiles(mp, flags, p);
	else
		error = ffs_flushfiles(mp, flags, p);
	if (error != 0)
		return (error);

	if (fs->fs_ronly == 0) {
		fs->fs_clean = (fs->fs_flags & FS_UNCLEAN) ? 0 : 1;
		error = ffs_sbupdate(ump, MNT_WAIT);
		if (error) {
			fs->fs_clean = 0;
			return (error);
		}
		free(fs->fs_contigdirs, M_UFSMNT);
	}
	ump->um_devvp->v_specmountpoint = NULL;

	vinvalbuf(ump->um_devvp, V_SAVE, NOCRED, p, 0, 0);
	error = VOP_CLOSE(ump->um_devvp, fs->fs_ronly ? FREAD : FREAD|FWRITE,
		NOCRED, p);
	vrele(ump->um_devvp);
	free(fs->fs_csp, M_UFSMNT);
	free(fs, M_UFSMNT);
	free(ump, M_UFSMNT);
	mp->mnt_data = (qaddr_t)0;
	mp->mnt_flag &= ~MNT_LOCAL;
	return (error);
}

/*
 * Flush out all the files in a filesystem.
 */
int
ffs_flushfiles(mp, flags, p)
	register struct mount *mp;
	int flags;
	struct proc *p;
{
	register struct ufsmount *ump;
	int error;

	ump = VFSTOUFS(mp);
	if (mp->mnt_flag & MNT_QUOTA) {
		int i;
		if ((error = vflush(mp, NULLVP, SKIPSYSTEM|flags)) != 0)
			return (error);
		for (i = 0; i < MAXQUOTAS; i++) {
			if (ump->um_quotas[i] == NULLVP)
				continue;
			quotaoff(p, mp, i);
		}
		/*
		 * Here we fall through to vflush again to ensure
		 * that we have gotten rid of all the system vnodes.
		 */
	}

	/*
	 * Flush all the files.
	 */
	if ((error = vflush(mp, NULL, flags)) != 0)
		return (error);
	/*
	 * Flush filesystem metadata.
	 */
	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY, p);
	error = VOP_FSYNC(ump->um_devvp, p->p_ucred, MNT_WAIT, p);
	VOP_UNLOCK(ump->um_devvp, 0, p);
	return (error);
}

/*
 * Get file system statistics.
 */
int
ffs_statfs(mp, sbp, p)
	struct mount *mp;
	register struct statfs *sbp;
	struct proc *p;
{
	register struct ufsmount *ump;
	register struct fs *fs;

	ump = VFSTOUFS(mp);
	fs = ump->um_fs;
	if (fs->fs_magic != FS_MAGIC)
		panic("ffs_statfs");
	sbp->f_bsize = fs->fs_fsize;
	sbp->f_iosize = fs->fs_bsize;
	sbp->f_blocks = fs->fs_dsize;
	sbp->f_bfree = fs->fs_cstotal.cs_nbfree * fs->fs_frag +
		fs->fs_cstotal.cs_nffree;
	sbp->f_bavail = sbp->f_bfree - fs->fs_dsize * fs->fs_minfree / 100;
	sbp->f_files = fs->fs_ncg * fs->fs_ipg - ROOTINO;
	sbp->f_ffree = fs->fs_cstotal.cs_nifree;
	if (sbp != &mp->mnt_stat) {
		bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
		bcopy(&mp->mnt_stat.mount_info.ufs_args,
		    &sbp->mount_info.ufs_args, sizeof(struct ufs_args));
	}
	strncpy(sbp->f_fstypename, mp->mnt_vfc->vfc_name, MFSNAMELEN);
	return (0);
}


struct ffs_sync_args {
	int allerror;
	struct proc *p;
	int waitfor;
	struct ucred *cred;
};

int
ffs_sync_vnode(struct vnode *vp, void *arg) {
	struct ffs_sync_args *fsa = arg;
	struct inode *ip;
	int error;

	ip = VTOI(vp);
	if (fsa->waitfor == MNT_LAZY ||
	    vp->v_type == VNON || 
	    ((ip->i_flag &
		(IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0	&&
		LIST_EMPTY(&vp->v_dirtyblkhd)) ) {
		simple_unlock(&vp->v_interlock);
		return (0);
	}

	if (vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, fsa->p))
		return (0);

	if ((error = VOP_FSYNC(vp, fsa->cred, fsa->waitfor, fsa->p)))
		fsa->allerror = error;
	VOP_UNLOCK(vp, 0, fsa->p);
	vrele(vp);

	return (0);
}

/*
 * Go through the disk queues to initiate sandbagged IO;
 * go through the inodes to write those that have been modified;
 * initiate the writing of the super block if it has been modified.
 *
 * Note: we are always called with the filesystem marked `MPBUSY'.
 */
int
ffs_sync(mp, waitfor, cred, p)
	struct mount *mp;
	int waitfor;
	struct ucred *cred;
	struct proc *p;
{
	struct ufsmount *ump = VFSTOUFS(mp);
	struct fs *fs;
	int error, allerror = 0, count;
	struct ffs_sync_args fsa;

	fs = ump->um_fs;
	/*
	 * Write back modified superblock.
	 * Consistency check that the superblock
	 * is still in the buffer cache.
	 */
	if (fs->fs_fmod != 0 && fs->fs_ronly != 0) {
		printf("fs = %s\n", fs->fs_fsmnt);
		panic("update: rofs mod");
	}

 loop:
	/*
	 * Write back each (modified) inode.
	 */
	fsa.allerror = 0;
	fsa.p = p;
	fsa.cred = cred;
	fsa.waitfor = waitfor;

	vfs_mount_foreach_vnode(mp, ffs_sync_vnode, &fsa);

	if (fsa.allerror != 0)
		allerror = fsa.allerror;
	/*
	 * Force stale file system control information to be flushed.
	 */
	if ((ump->um_mountp->mnt_flag & MNT_SOFTDEP) && waitfor == MNT_WAIT) {
		if ((error = softdep_flushworklist(ump->um_mountp, &count, p)))
			allerror = error;
		/* Flushed work items may create new vnodes to clean */
		if (count) 
			goto loop;
	}
	if (waitfor != MNT_LAZY) {
		if (ump->um_mountp->mnt_flag & MNT_SOFTDEP)
			waitfor = MNT_NOWAIT;
		vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY, p);
		if ((error = VOP_FSYNC(ump->um_devvp, cred, waitfor, p)) != 0)
			allerror = error;
		VOP_UNLOCK(ump->um_devvp, 0, p);
	}
	qsync(mp);
	/*
	 * Write back modified superblock.
	 */

	if (fs->fs_fmod != 0 && (error = ffs_sbupdate(ump, waitfor)) != 0)
		allerror = error;

	return (allerror);
}

/*
 * Look up a FFS dinode number to find its incore vnode, otherwise read it
 * in from disk.  If it is in core, wait for the lock bit to clear, then
 * return the inode locked.  Detection and handling of mount points must be
 * done by the calling routine.
 */
int
ffs_vget(mp, ino, vpp)
	struct mount *mp;
	ino_t ino;
	struct vnode **vpp;
{
	register struct fs *fs;
	register struct inode *ip;
	struct ufsmount *ump;
	struct buf *bp;
	struct vnode *vp;
	dev_t dev;
	int error;

	ump = VFSTOUFS(mp);
	dev = ump->um_dev;

retry:
	if ((*vpp = ufs_ihashget(dev, ino)) != NULL)
		return (0);

	/* Allocate a new vnode/inode. */
	if ((error = getnewvnode(VT_UFS, mp, ffs_vnodeop_p, &vp)) != 0) {
		*vpp = NULL;
		return (error);
	}
#ifdef LOCKDEBUG
	vp->v_flag |= VLOCKSWORK;
#endif
	/* XXX - we use the same pool for ffs and mfs */
	ip = pool_get(&ffs_ino_pool, PR_WAITOK);
	bzero((caddr_t)ip, sizeof(struct inode));
	lockinit(&ip->i_lock, PINOD, "inode", 0, 0);
	vp->v_data = ip;
	ip->i_vnode = vp;
	ip->i_fs = fs = ump->um_fs;
	ip->i_dev = dev;
	ip->i_number = ino;
	ip->i_vtbl = &ffs_vtbl;

	/*
	 * Put it onto its hash chain and lock it so that other requests for
	 * this inode will block if they arrive while we are sleeping waiting
	 * for old data structures to be purged or for the contents of the
	 * disk portion of this inode to be read.
	 */
	error = ufs_ihashins(ip);
	
	if (error) {
		/*
		 * VOP_INACTIVE will treat this as a stale file
		 * and recycle it quickly
		 */
		vrele(vp);

		if (error == EEXIST)
			goto retry;

		return (error);
	}


	/* Read in the disk contents for the inode, copy into the inode. */
	error = bread(ump->um_devvp, fsbtodb(fs, ino_to_fsba(fs, ino)),
		      (int)fs->fs_bsize, NOCRED, &bp);
	if (error) {
		/*
		 * The inode does not contain anything useful, so it would
		 * be misleading to leave it on its hash chain. With mode
		 * still zero, it will be unlinked and returned to the free
		 * list by vput().
		 */
		vput(vp);
		brelse(bp);
		*vpp = NULL;
		return (error);
	}
	ip->i_din.ffs_din = *((struct dinode *)bp->b_data + ino_to_fsbo(fs, ino));
	if (DOINGSOFTDEP(vp))
		softdep_load_inodeblock(ip);
	else
		ip->i_effnlink = ip->i_ffs_nlink;
	brelse(bp);

	/*
	 * Initialize the vnode from the inode, check for aliases.
	 * Note that the underlying vnode may have changed.
	 */
	error = ufs_vinit(mp, ffs_specop_p, FFS_FIFOOPS, &vp);
	if (error) {
		vput(vp);
		*vpp = NULL;
		return (error);
	}
	/*
	 * Finish inode initialization now that aliasing has been resolved.
	 */
	ip->i_devvp = ump->um_devvp;
	VREF(ip->i_devvp);
	/*
	 * Set up a generation number for this inode if it does not
	 * already have one. This should only happen on old filesystems.
	 */
	if (ip->i_ffs_gen == 0) {
		ip->i_ffs_gen = arc4random();
		if (ip->i_ffs_gen == 0 || ip->i_ffs_gen == -1)
			ip->i_ffs_gen = 1;		/* shouldn't happen */
		if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0)
			ip->i_flag |= IN_MODIFIED;
	}
	/*
	 * Ensure that uid and gid are correct. This is a temporary
	 * fix until fsck has been changed to do the update.
	 */
	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
		ip->i_ffs_uid = ip->i_din.ffs_din.di_ouid;	/* XXX */
		ip->i_ffs_gid = ip->i_din.ffs_din.di_ogid;	/* XXX */
	}							/* XXX */

	*vpp = vp;
	return (0);
}

/*
 * File handle to vnode
 *
 * Have to be really careful about stale file handles:
 * - check that the inode number is valid
 * - call ffs_vget() to get the locked inode
 * - check for an unallocated inode (i_mode == 0)
 */
int
ffs_fhtovp(mp, fhp, vpp)
	register struct mount *mp;
	struct fid *fhp;
	struct vnode **vpp;
{
	register struct ufid *ufhp;
	struct fs *fs;

	ufhp = (struct ufid *)fhp;
	fs = VFSTOUFS(mp)->um_fs;
	if (ufhp->ufid_ino < ROOTINO ||
	    ufhp->ufid_ino >= fs->fs_ncg * fs->fs_ipg)
		return (ESTALE);
	return (ufs_fhtovp(mp, ufhp, vpp));
}

/*
 * Vnode pointer to File handle
 */
/* ARGSUSED */
int
ffs_vptofh(vp, fhp)
	struct vnode *vp;
	struct fid *fhp;
{
	register struct inode *ip;
	register struct ufid *ufhp;

	ip = VTOI(vp);
	ufhp = (struct ufid *)fhp;
	ufhp->ufid_len = sizeof(struct ufid);
	ufhp->ufid_ino = ip->i_number;
	ufhp->ufid_gen = ip->i_ffs_gen;
	return (0);
}

/*
 * Write a superblock and associated information back to disk.
 */
int
ffs_sbupdate(mp, waitfor)
	struct ufsmount *mp;
	int waitfor;
{
	register struct fs *dfs, *fs = mp->um_fs;
	register struct buf *bp;
	int blks;
	caddr_t space;
	int i, size, error, allerror = 0;

	/*
	 * First write back the summary information.
	 */
	blks = howmany(fs->fs_cssize, fs->fs_fsize);
	space = (caddr_t)fs->fs_csp;
	for (i = 0; i < blks; i += fs->fs_frag) {
		size = fs->fs_bsize;
		if (i + fs->fs_frag > blks)
			size = (blks - i) * fs->fs_fsize;
		bp = getblk(mp->um_devvp, fsbtodb(fs, fs->fs_csaddr + i),
			    size, 0, 0);
		bcopy(space, bp->b_data, (u_int)size);
		space += size;
		if (waitfor != MNT_WAIT)
			bawrite(bp);
		else if ((error = bwrite(bp)))
			allerror = error;
	}
	/*
	 * Now write back the superblock itself. If any errors occurred
	 * up to this point, then fail so that the superblock avoids
	 * being written out as clean.
	 */
	if (allerror)
		return (allerror);

	bp = getblk(mp->um_devvp, SBOFF >> (fs->fs_fshift - fs->fs_fsbtodb),
		    (int)fs->fs_sbsize, 0, 0);
	fs->fs_fmod = 0;
	fs->fs_time = time.tv_sec;
	bcopy((caddr_t)fs, bp->b_data, (u_int)fs->fs_sbsize);
	/* Restore compatibility to old file systems.		   XXX */
	dfs = (struct fs *)bp->b_data;				/* XXX */
	if (fs->fs_postblformat == FS_42POSTBLFMT)		/* XXX */
		dfs->fs_nrpos = -1;				/* XXX */
	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
		int32_t *lp, tmp;				/* XXX */
								/* XXX */
		lp = (int32_t *)&dfs->fs_qbmask;		/* XXX */
		tmp = lp[4];					/* XXX */
		for (i = 4; i > 0; i--)				/* XXX */
			lp[i] = lp[i-1];			/* XXX */
		lp[0] = tmp;					/* XXX */
	}							/* XXX */
	dfs->fs_maxfilesize = mp->um_savedmaxfilesize;		/* XXX */
	if (waitfor != MNT_WAIT)
		bawrite(bp);
	else if ((error = bwrite(bp)))
		allerror = error;
	return (allerror);
}

int
ffs_init(vfsp)
	struct vfsconf *vfsp;
{
	static int done;

	if (done)
		return (0);
	done = 1;
	pool_init(&ffs_ino_pool, sizeof(struct inode), 0, 0, 0, "ffsino",
	    0, pool_page_alloc_nointr, pool_page_free_nointr, M_FFSNODE);
	softdep_initialize();
	return (ufs_init(vfsp));
}

/*
 * fast filesystem related variables.
 */
int
ffs_sysctl(name, namelen, oldp, oldlenp, newp, newlen, p)
	int *name;
	u_int namelen;
	void *oldp;
	size_t *oldlenp;
	void *newp;
	size_t newlen;
	struct proc *p;
{
	extern int doclusterread, doclusterwrite, doreallocblks, doasyncfree;

	/* all sysctl names at this level are terminal */
	if (namelen != 1)
		return (ENOTDIR);		/* overloaded */

	switch (name[0]) {
	case FFS_CLUSTERREAD:
		return (sysctl_int(oldp, oldlenp, newp, newlen,
		    &doclusterread));
	case FFS_CLUSTERWRITE:
		return (sysctl_int(oldp, oldlenp, newp, newlen,
		    &doclusterwrite));
	case FFS_REALLOCBLKS:
		return (sysctl_int(oldp, oldlenp, newp, newlen,
		    &doreallocblks));
	case FFS_ASYNCFREE:
		return (sysctl_int(oldp, oldlenp, newp, newlen, &doasyncfree));
	default:
		return (EOPNOTSUPP);
	}
	/* NOTREACHED */
}