usr.sbin/makefs: Sync with sys/vfs/hammer2

[dragonfly.git] / sys / vfs / ufs / ffs_vfsops.c

/*
 * 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. 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        8.31 (Berkeley) 5/20/95
 * $FreeBSD: src/sys/ufs/ffs/ffs_vfsops.c,v 1.117.2.10 2002/06/23 22:34:52 iedowse Exp $
 */

#include "opt_quota.h"

#include <sys/disk.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/nlookup.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/diskslice.h>
#include <sys/malloc.h>

#include "quota.h"
#include "ufsmount.h"
#include "inode.h"
#include "ufs_extern.h"

#include "fs.h"
#include "ffs_extern.h"

#include <vm/vm.h>
#include <vm/vm_page.h>
#include <vm/vm_zone.h>

#include <sys/buf2.h>

static MALLOC_DEFINE(M_FFSNODE, "FFS node", "FFS vnode private part");

static int      ffs_sbupdate (struct ufsmount *, int);
static int      ffs_reload (struct mount *, struct ucred *);
static int      ffs_oldfscompat (struct fs *);
static int      ffs_mount (struct mount *, char *, caddr_t, struct ucred *);
static int      ffs_init (struct vfsconf *);

static struct vfsops ufs_vfsops = {
        .vfs_flags =            0,
        .vfs_mount =            ffs_mount,
        .vfs_unmount =          ffs_unmount,
        .vfs_root =             ufs_root,
        .vfs_quotactl =         ufs_quotactl,
        .vfs_statfs =           ffs_statfs,
        .vfs_sync =             ffs_sync,
        .vfs_vget =             ffs_vget,
        .vfs_fhtovp =           ffs_fhtovp,
        .vfs_checkexp =         ufs_check_export,
        .vfs_vptofh =           ffs_vptofh,
        .vfs_init =             ffs_init,
};

VFS_SET(ufs_vfsops, ufs, 0);
MODULE_VERSION(ufs, 1);

extern struct vop_ops ffs_vnode_vops;
extern struct vop_ops ffs_spec_vops;
extern struct vop_ops ffs_fifo_vops;

/*
 * ffs_mount
 *
 * Called when mounting local physical media
 *
 * PARAMETERS:
 *              mountroot
 *                      mp      mount point structure
 *                      path    NULL (flag for root mount!!!)
 *                      data    <unused>
 *                      p       process (user credentials check [statfs])
 *
 *              mount
 *                      mp      mount point structure
 *                      path    path to mount point
 *                      data    pointer to argument struct in user space
 *                      p       process (user credentials check)
 *
 * RETURNS:     0       Success
 *              !0      error number (errno.h)
 *
 * LOCK STATE:
 *
 *              ENTRY
 *                      mount point is locked
 *              EXIT
 *                      mount point is locked
 *
 * NOTES:
 *              A NULL path can be used for a flag since the mount
 *              system call will fail with EFAULT in copyinstr in
 *              nlookup() if it is a genuine NULL from the user.
 */
static int
ffs_mount(struct mount *mp,             /* mount struct pointer */
          char *path,                   /* path to mount point */
          caddr_t data,                 /* arguments to FS specific mount */
          struct ucred  *cred)          /* process requesting mount */
{
        size_t          size;
        int             error;
        struct vnode    *devvp;

        struct ufs_args args;
        struct ufsmount *ump = NULL;
        struct fs *fs;
        int flags, ronly = 0;
        mode_t accessmode;
        struct nlookupdata nd;
        struct vnode *rootvp;

        devvp = NULL;
        error = 0;

        /*
         * Use NULL path to flag a root mount
         */
        if (path == NULL) {
                /*
                 ***
                 * Mounting root filesystem
                 ***
                 */
        
                if ((error = bdevvp(rootdev, &rootvp))) {
                        kprintf("ffs_mountroot: can't find rootvp\n");
                        return (error);
                }

                if( ( error = ffs_mountfs(rootvp, mp, M_FFSNODE)) != 0) {
                        /* fs specific cleanup (if any)*/
                        goto error_1;
                }
                devvp = rootvp;

                goto dostatfs;          /* success*/

        }

        /*
         ***
         * Mounting non-root filesystem or updating a filesystem
         ***
         */

        /* copy in user arguments*/
        error = copyin(data, (caddr_t)&args, sizeof (struct ufs_args));
        if (error)
                goto error_1;           /* can't get arguments*/

        /*
         * 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;   /* MNT_RELOAD might change this */
                if (ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
                        /*
                         * Flush any dirty data.
                         */
                        VFS_SYNC(mp, MNT_WAIT);
                        /*
                         * Check for and optionally get rid of files open
                         * for writing.
                         */
                        flags = WRITECLOSE;
                        if (mp->mnt_flag & MNT_FORCE)
                                flags |= FORCECLOSE;
                        if (mp->mnt_flag & MNT_SOFTDEP) {
                                error = softdep_flushfiles(mp, flags);
                        } else {
                                error = ffs_flushfiles(mp, flags);
                        }
                        ronly = 1;
                }
                if (!error && (mp->mnt_flag & MNT_RELOAD)) {
                        error = ffs_reload(mp, NULL);
                }
                if (error) {
                        goto error_1;
                }
                if (ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
                        /*
                         * If upgrade to read-write by non-root, then verify
                         * that user has necessary permissions on the device.
                         */
                        if (cred->cr_uid != 0) {
                                vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
                                if ((error = VOP_EACCESS(devvp, VREAD | VWRITE,
                                    cred)) != 0) {
                                        vn_unlock(devvp);
                                        return (error);
                                }
                                vn_unlock(devvp);
                        }

                        fs->fs_flags &= ~FS_UNCLEAN;
                        if (fs->fs_clean == 0) {
                                fs->fs_flags |= FS_UNCLEAN;
                                if (mp->mnt_flag & MNT_FORCE) {
                                        kprintf(
"WARNING: %s was not properly dismounted\n",
                                            fs->fs_fsmnt);
                                } else {
                                        kprintf(
"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
                                            fs->fs_fsmnt);
                                        error = EPERM;
                                        goto error_1;
                                }
                        }

                        /* check to see if we need to start softdep */
                        if (fs->fs_flags & FS_DOSOFTDEP) {
                                error = softdep_mount(devvp, mp, fs);
                                if (error)
                                        goto error_1;
                        }
                        ronly = 0;
                }
                /*
                 * Soft updates is incompatible with "async",
                 * so if we are doing softupdates stop the user
                 * from setting the async flag in an update.
                 * Softdep_mount() clears it in an initial mount 
                 * or ro->rw remount.
                 */
                if (mp->mnt_flag & MNT_SOFTDEP) {
                        mp->mnt_flag &= ~MNT_ASYNC;
                }
                /* if not updating name...*/
                if (args.fspec == NULL) {
                        /*
                         * Process export requests.  Jumping to "success"
                         * will return the vfs_export() error code.
                         */
                        error = vfs_export(mp, &ump->um_export, &args.export);
                        goto success;
                }
        }

        /*
         * Not an update, or updating the name: look up the name
         * and verify that it refers to a sensible block device.
         */
        devvp = NULL;
        error = nlookup_init(&nd, args.fspec, UIO_USERSPACE, NLC_FOLLOW);
        if (error == 0)
                error = nlookup(&nd);
        if (error == 0)
                error = cache_vref(&nd.nl_nch, nd.nl_cred, &devvp);
        nlookup_done(&nd);
        if (error)
                goto error_1;

        if (!vn_isdisk(devvp, &error))
                goto error_2;

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

        if (mp->mnt_flag & MNT_UPDATE) {
                /*
                 * UPDATE - make sure the resolved vnode represents the same
                 * device. Since devfs, devvp->v_rdev can be used directly as
                 * it is always associated as long as the vnode exists.
                 *
                 * Our current open/writecount state is associated with
                 * um_devvp, so continue using um_devvp and throw away devvp.
                 */
                if (devvp != ump->um_devvp) {
                        if (devvp->v_rdev == ump->um_devvp->v_rdev) {
                                vrele(devvp);
                                devvp = ump->um_devvp;
                        } else {
                                kprintf("cannot update mount, v_rdev does"
                                        " not match (%p vs %p)\n",
                                        devvp->v_rdev, ump->um_devvp->v_rdev);
                                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 {
                /*
                 ********************
                 * NEW MOUNT
                 ********************
                 */

                /* 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);

                /* Save "last mounted on" info for mount point (NULL pad)*/
                bzero(mp->mnt_stat.f_mntonname,
                      sizeof(mp->mnt_stat.f_mntonname));
                if (path) {
                        copyinstr(path, mp->mnt_stat.f_mntonname,
                                  sizeof(mp->mnt_stat.f_mntonname) - 1,
                                  &size);
                } else {        /* Root mount */
                        mp->mnt_stat.f_mntonname[0] = '/';
                }

                error = ffs_mountfs(devvp, mp, M_FFSNODE);
        }
        if (error) {
                goto error_2;
        }

dostatfs:
        /*
         * Initialize FS stat information in mount struct; uses
         * mp->mnt_stat.f_mntfromname.
         *
         * This code is common to root and non-root mounts
         */
        (void)VFS_STATFS(mp, &mp->mnt_stat, cred);

        goto success;


error_2:        /* error with devvp held*/

        /* release devvp before failing*/
        vrele(devvp);

error_1:        /* no state to back out*/

success:
        if (!error && 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;

                        /*
                         * The device must be re-opened as appropriate or
                         * the device close at unmount time will panic.
                         */
                        vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
                        if (ronly) {
                                VOP_OPEN(devvp, FREAD, FSCRED, NULL);
                                VOP_CLOSE(devvp, FREAD|FWRITE, NULL);
                        } else {
                                VOP_OPEN(devvp, FREAD|FWRITE, FSCRED, NULL);
                                VOP_CLOSE(devvp, FREAD, NULL);
                        }
                        vn_unlock(devvp);
                        ffs_sbupdate(ump, MNT_WAIT);
                }
        }
        return (error);
}

/*
 * 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.
 */

static int ffs_reload_scan2(struct mount *mp, struct vnode *vp, void *data);

struct scaninfo {
        int rescan;
        struct fs *fs;
        struct vnode *devvp;
        int waitfor;
        int allerror;
};

static int
ffs_reload(struct mount *mp, struct ucred *cred)
{
        struct vnode *devvp;
        void *space;
        struct buf *bp;
        struct fs *fs, *newfs;
        int i, blks, size, error;
        struct scaninfo scaninfo;
        int32_t *lp;

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

        /*
         * The backing device must be VMIO-capable because we use getblk().
         * NOTE: the MFS driver now returns a VMIO-enabled descriptor.
         */
        if (devvp->v_object == NULL)
                panic("ffs_reload: devvp has no VM object!");

        /*
         * Step 2: re-read superblock from disk.
         */
        if ((error = bread(devvp, SBOFF, SBSIZE, &bp)) != 0) {
                brelse(bp);
                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(mp)->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_contigdirs = fs->fs_contigdirs;
        /* The filesystem is still read-only. */
        newfs->fs_ronly = 1;
        bcopy(newfs, fs, (uint)fs->fs_sbsize);
        if (fs->fs_sbsize < SBSIZE)
                bp->b_flags |= B_INVAL;
        brelse(bp);
        mp->mnt_maxsymlinklen = fs->fs_maxsymlinklen;
        ffs_oldfscompat(fs);
        /* An old fsck may have zeroed these fields, so recheck them. */
        if (fs->fs_avgfilesize <= 0)            /* XXX */
                fs->fs_avgfilesize = AVFILESIZ; /* XXX */
        if (fs->fs_avgfpdir <= 0)               /* XXX */
                fs->fs_avgfpdir = AFPDIR;       /* XXX */

        /*
         * Step 3: re-read summary information from disk.
         */
        blks = howmany(fs->fs_cssize, fs->fs_fsize);
        space = 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, fsbtodoff(fs, fs->fs_csaddr + i), size, &bp);
                if (error) {
                        brelse(bp);
                        return (error);
                }
                bcopy(bp->b_data, space, (uint)size);
                space = (char *)space + size;
                brelse(bp);
        }
        /*
         * 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;
        }

        scaninfo.rescan = 0;
        scaninfo.fs = fs;
        scaninfo.devvp = devvp;
        while (error == 0 && scaninfo.rescan) {
                scaninfo.rescan = 0;
                error = vmntvnodescan(mp, VMSC_GETVX, 
                                        NULL, ffs_reload_scan2, &scaninfo);
        }
        return(error);
}

static int
ffs_reload_scan2(struct mount *mp, struct vnode *vp, void *data)
{
        struct scaninfo *info = data;
        struct inode *ip;
        struct buf *bp;
        int error;

        /*
         * Try to recycle
         */
        if (vrecycle(vp))
                return(0);

        if (vinvalbuf(vp, 0, 0, 0))
                panic("ffs_reload: dirty2");
        /*
         * Step 6: re-read inode data for all active vnodes.
         */
        ip = VTOI(vp);
        error = bread(info->devvp,
                    fsbtodoff(info->fs, ino_to_fsba(info->fs, ip->i_number)),
                    (int)info->fs->fs_bsize, &bp);
        if (error) {
                brelse(bp);
                return (error);
        }
        ip->i_din = *((struct ufs1_dinode *)bp->b_data +
            ino_to_fsbo(info->fs, ip->i_number));
        ip->i_effnlink = ip->i_nlink;
        brelse(bp);
        return(0);
}

/*
 * Common code for mount and mountroot
 */
int
ffs_mountfs(struct vnode *devvp, struct mount *mp, struct malloc_type *mtype)
{
        struct mount *mptmp;
        struct ufsmount *ump;
        struct buf *bp;
        struct fs *fs;
        cdev_t dev;
        void *space;
        int error, i, blks, size, ronly;
        int32_t *lp;
        uint64_t maxfilesize;                                   /* XXX */

        /*
         * Disallow multiple mounts of the same device.
         * Disallow mounting of a device that is currently in use
         * Flush out any old buffers remaining from a previous use.
         */
        error = vfs_mountedon(devvp);
        if (error)
                return (error);
        if (vcount(devvp) > 0)
                return (EBUSY);
        vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
        error = vinvalbuf(devvp, V_SAVE, 0, 0);
        vn_unlock(devvp);
        if (error)
                return (error);

        ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
        vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
        error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, NULL);
        vn_unlock(devvp);
        if (error)
                return (error);
        dev = devvp->v_rdev;
        if (dev->si_iosize_max != 0)
                mp->mnt_iosize_max = dev->si_iosize_max;
        if (mp->mnt_iosize_max > MAXPHYS)
                mp->mnt_iosize_max = MAXPHYS;

        /*
         * The backing device must be VMIO-capable because we use getblk().
         * NOTE: the MFS driver now returns a VMIO-enabled descriptor.
         * The VOP_OPEN() call above should have associated a VM object
         * with devvp.
         */
        if (devvp->v_object == NULL)
                panic("ffs_reload: devvp has no VM object!");

        bp = NULL;
        ump = NULL;
        if ((error = bread(devvp, SBOFF, SBSIZE, &bp)) != 0)
                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 = EINVAL;         /* XXX needs translation */
                goto out;
        }
        fs->fs_fmod = 0;
        fs->fs_flags &= ~FS_UNCLEAN;
        if (fs->fs_clean == 0) {
                fs->fs_flags |= FS_UNCLEAN;
                if (ronly || (mp->mnt_flag & MNT_FORCE)) {
                        kprintf(
"WARNING: %s was not properly dismounted\n",
                            fs->fs_fsmnt);
                } else {
                        kprintf(
"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;          /* needs translation */
                goto out;
        }
        ump = kmalloc(sizeof *ump, M_UFSMNT, M_WAITOK | M_ZERO);
        ump->um_malloctype = mtype;
        ump->um_i_effnlink_valid = 1;
        ump->um_fs = kmalloc((u_long)fs->fs_sbsize, M_UFSMNT,
            M_WAITOK);
        bcopy(bp->b_data, ump->um_fs, (uint)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);
        size += fs->fs_ncg * sizeof(uint8_t);
        space = kmalloc((u_long)size, M_UFSMNT, M_WAITOK);
        fs->fs_csp = 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;
                if ((error = bread(devvp, fsbtodoff(fs, fs->fs_csaddr + i),
                                   size, &bp)) != 0) {
                        kfree(fs->fs_csp, M_UFSMNT);
                        goto out;
                }
                bcopy(bp->b_data, space, (uint)size);
                space = (char *)space + size;
                brelse(bp);
                bp = NULL;
        }
        if (fs->fs_contigsumsize > 0) {
                fs->fs_maxcluster = lp = space;
                for (i = 0; i < fs->fs_ncg; i++)
                        *lp++ = fs->fs_contigsumsize;
                space = lp;
        }
        size = fs->fs_ncg * sizeof(uint8_t);
        fs->fs_contigdirs = (uint8_t *)space;
        bzero(fs->fs_contigdirs, size);
        /* Compatibility for old filesystems       XXX */
        if (fs->fs_avgfilesize <= 0)            /* XXX */
                fs->fs_avgfilesize = AVFILESIZ; /* XXX */
        if (fs->fs_avgfpdir <= 0)               /* XXX */
                fs->fs_avgfpdir = AFPDIR;       /* XXX */
        mp->mnt_data = (qaddr_t)ump;
        mp->mnt_stat.f_fsid.val[0] = fs->fs_id[0];
        mp->mnt_stat.f_fsid.val[1] = fs->fs_id[1];
        if (fs->fs_id[0] == 0 || fs->fs_id[1] == 0) {
                vfs_getnewfsid(mp);
        } else if ((mptmp = vfs_getvfs(&mp->mnt_stat.f_fsid)) != NULL) {
                vfs_getnewfsid(mp);
                mount_drop(mptmp);
        }
        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;
        dev->si_mountpoint = mp;
        ffs_oldfscompat(fs);

        /* restore "last mounted on" here */
        bzero(fs->fs_fsmnt, sizeof(fs->fs_fsmnt));
        ksnprintf(fs->fs_fsmnt, sizeof(fs->fs_fsmnt),
                 "%s", mp->mnt_stat.f_mntonname);

        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;
        }

        ufs_ihashinit(ump);
        ump->um_savedmaxfilesize = fs->fs_maxfilesize;          /* XXX */
        maxfilesize = (uint64_t)0x40000000 * fs->fs_bsize - 1;  /* XXX */
        /* Enforce limit caused by vm object backing (32 bits vm_pindex_t). */
        if (maxfilesize > (uint64_t)0x80000000u * PAGE_SIZE - 1)
                maxfilesize = (uint64_t)0x80000000u * PAGE_SIZE - 1;
        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)) != 0) {
                        kfree(fs->fs_csp, M_UFSMNT);
                        goto out;
                }
                fs->fs_fmod = 1;
                fs->fs_clean = 0;
                (void) ffs_sbupdate(ump, MNT_WAIT);
        }
        vfs_add_vnodeops(mp, &ffs_vnode_vops, &mp->mnt_vn_norm_ops);
        vfs_add_vnodeops(mp, &ffs_spec_vops, &mp->mnt_vn_spec_ops);
        vfs_add_vnodeops(mp, &ffs_fifo_vops, &mp->mnt_vn_fifo_ops);

        return (0);
out:
        dev->si_mountpoint = NULL;
        if (bp)
                brelse(bp);
        vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
        VOP_CLOSE(devvp, ronly ? FREAD : FREAD|FWRITE, NULL);
        vn_unlock(devvp);
        if (ump) {
                ufs_ihashuninit(ump);
                kfree(ump->um_fs, M_UFSMNT);
                kfree(ump, M_UFSMNT);
                mp->mnt_data = (qaddr_t)0;
        }
        return (error);
}

/*
 * Sanity checks for old filesystems.
 *
 * XXX - goes away some day.
 */
static int
ffs_oldfscompat(struct fs *fs)
{
        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 */
#if 0
                int i;                                          /* XXX */
                uint64_t sizepb = fs->fs_bsize;         /* XXX */
                                                                /* XXX */
                fs->fs_maxfilesize = fs->fs_bsize * UFS_NDADDR - 1; /* XXX */
                for (i = 0; i < UFS_NIADDR; i++) {              /* XXX */
                        sizepb *= NINDIR(fs);                   /* XXX */
                        fs->fs_maxfilesize += sizepb;           /* XXX */
                }                                               /* XXX */
#endif
                fs->fs_maxfilesize = (u_quad_t) 1LL << 39;
                fs->fs_qbmask = ~fs->fs_bmask;                  /* XXX */
                fs->fs_qfmask = ~fs->fs_fmask;                  /* XXX */
        }                                                       /* XXX */
        return (0);
}

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

        flags = 0;
        if (mntflags & MNT_FORCE) {
                flags |= FORCECLOSE;
        }
        if (mp->mnt_flag & MNT_SOFTDEP) {
                if ((error = softdep_flushfiles(mp, flags)) != 0)
                        return (error);
        } else {
                if ((error = ffs_flushfiles(mp, flags)) != 0)
                        return (error);
        }
        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        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);
                }
        }
        ump->um_devvp->v_rdev->si_mountpoint = NULL;

        vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
        vinvalbuf(ump->um_devvp, V_SAVE, 0, 0);
        error = VOP_CLOSE(ump->um_devvp, 
                        fs->fs_ronly ? FREAD : FREAD|FWRITE,
                        NULL);
        vn_unlock(ump->um_devvp);

        vrele(ump->um_devvp);

        ufs_ihashuninit(ump);
        kfree(fs->fs_csp, M_UFSMNT);
        kfree(fs, M_UFSMNT);
        kfree(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(struct mount *mp, int flags)
{
        struct ufsmount *ump;
        int error;

        ump = VFSTOUFS(mp);
#ifdef QUOTA
        if (mp->mnt_flag & MNT_QUOTA) {
                int i;
                error = vflush(mp, 0, SKIPSYSTEM|flags);
                if (error)
                        return (error);
                /* Find out how many quota files  we have open. */
                for (i = 0; i < MAXQUOTAS; i++) {
                        if (ump->um_quotas[i] == NULLVP)
                                continue;
                        ufs_quotaoff(mp, i);
                }
                /*
                 * Here we fall through to vflush again to ensure
                 * that we have gotten rid of all the system vnodes.
                 */
        }
#endif
        /*
         * Flush all the files.
         */
        if ((error = vflush(mp, 0, flags)) != 0)
                return (error);
        /*
         * Flush filesystem metadata.
         */
        vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
        error = VOP_FSYNC(ump->um_devvp, MNT_WAIT, 0);
        vn_unlock(ump->um_devvp);
        return (error);
}

/*
 * Get filesystem statistics.
 */
int
ffs_statfs(struct mount *mp, struct statfs *sbp, struct ucred *cred)
{
        struct ufsmount *ump;
        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 = freespace(fs, fs->fs_minfree);
        sbp->f_files =  fs->fs_ncg * fs->fs_ipg - UFS_ROOTINO;
        sbp->f_ffree = fs->fs_cstotal.cs_nifree;
        if (sbp != &mp->mnt_stat) {
                sbp->f_type = mp->mnt_vfc->vfc_typenum;
                bcopy((caddr_t)mp->mnt_stat.f_mntfromname,
                        (caddr_t)&sbp->f_mntfromname[0], MNAMELEN);
        }
        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'.
 */


static int ffs_sync_scan1(struct mount *mp, struct vnode *vp, void *data);
static int ffs_sync_scan2(struct mount *mp, struct vnode *vp, void *data);

int
ffs_sync(struct mount *mp, int waitfor)
{
        struct ufsmount *ump = VFSTOUFS(mp);
        struct fs *fs;
        int error;
        struct scaninfo scaninfo;

        fs = ump->um_fs;
        if (fs->fs_fmod != 0 && fs->fs_ronly != 0) {            /* XXX */
                kprintf("fs = %s\n", fs->fs_fsmnt);
                panic("ffs_sync: rofs mod");
        }

        /*
         * Write back each (modified) inode.
         */
        scaninfo.allerror = 0;
        scaninfo.rescan = 1;
        scaninfo.waitfor = waitfor;
        while (scaninfo.rescan) {
                scaninfo.rescan = 0;
                vmntvnodescan(mp, VMSC_GETVP|VMSC_NOWAIT,
                                ffs_sync_scan1, ffs_sync_scan2, &scaninfo);
        }

        /*
         * Force stale filesystem control information to be flushed.
         */
        if ((waitfor & MNT_LAZY) == 0) {
                if (ump->um_mountp->mnt_flag & MNT_SOFTDEP)
                        waitfor = MNT_NOWAIT;
                vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
                if ((error = VOP_FSYNC(ump->um_devvp, waitfor, 0)) != 0)
                        scaninfo.allerror = error;
                vn_unlock(ump->um_devvp);
        }
#ifdef QUOTA
        ufs_qsync(mp);
#endif
        /*
         * Write back modified superblock.
         */
        if (fs->fs_fmod != 0 && (error = ffs_sbupdate(ump, waitfor)) != 0)
                scaninfo.allerror = error;
        return (scaninfo.allerror);
}

static int
ffs_sync_scan1(struct mount *mp, struct vnode *vp, void *data)
{
        struct inode *ip;

        /*
         * Depend on the mount list's vnode lock to keep things stable 
         * enough for a quick test.  Since there might be hundreds of 
         * thousands of vnodes, we cannot afford even a subroutine
         * call unless there's a good chance that we have work to do.
         */
        ip = VTOI(vp);
        /* Restart out whole search if this guy is locked
         * or is being reclaimed.
         */
        if (vp->v_type == VNON || (ip == NULL) || ((ip->i_flag &
             (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
             RB_EMPTY(&vp->v_rbdirty_tree))) {
                return(-1);
        }
        return(0);
}

static int 
ffs_sync_scan2(struct mount *mp, struct vnode *vp, void *data)
{
        struct scaninfo *info = data;
        struct inode *ip;
        int error;

        /*
         * We have to recheck after having obtained the vnode interlock.
         */
        ip = VTOI(vp);
        if (vp->v_type == VNON || vp->v_type == VBAD ||
             ((ip->i_flag &
              (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
             RB_EMPTY(&vp->v_rbdirty_tree))) {
                return(0);
        }
        if (vp->v_type != VCHR) {
                if ((error = VOP_FSYNC(vp, info->waitfor, 0)) != 0)
                        info->allerror = error;
        } else {
                /*
                 * We must reference the vp to prevent it from
                 * getting ripped out from under ffs_update, since
                 * we are not holding a vnode lock.
                 */
                /* ffs_update(vp, waitfor == MNT_WAIT); */
                ffs_update(vp, 0);
        }
        return(0);
}

/*
 * 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(struct mount *mp, struct vnode *dvp, ino_t ino, struct vnode **vpp)
{
        struct fs *fs;
        struct inode *ip;
        struct ufsmount *ump;
        struct buf *bp;
        struct vnode *vp;
        cdev_t dev;
        int error;

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

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

        /*
         * If this MALLOC() is performed after the getnewvnode()
         * it might block, leaving a vnode with a NULL v_data to be
         * found by ffs_sync() if a sync happens to fire right then,
         * which will cause a panic because ffs_sync() blindly
         * dereferences vp->v_data (as well it should).
         *
         * XXX this may no longer be true since getnewvnode returns a
         * VX locked vnode now.
         */
        ip = kmalloc(sizeof(struct inode), ump->um_malloctype,
                     M_WAITOK | M_ZERO);

        /* Allocate a new vnode/inode. */
        error = getnewvnode(VT_UFS, mp, &vp, VLKTIMEOUT, LK_CANRECURSE);
        if (error) {
                *vpp = NULL;
                kfree(ip, ump->um_malloctype);
                return (error);
        }
        ip->i_vnode = vp;
        ip->i_fs = fs = ump->um_fs;
        ip->i_dev = dev;
        ip->i_number = ino;
#ifdef QUOTA
        {
                int i;
                for (i = 0; i < MAXQUOTAS; i++)
                        ip->i_dquot[i] = NODQUOT;
        }
#endif

        /*
         * Insert it into the inode hash table.
         */
        if (ufs_ihashins(ump, ip) != 0) {
                kprintf("debug: ufs ihashins collision, retrying inode %ld\n",
                        (long) ip->i_number);
                *vpp = NULL;
                vp->v_type = VBAD;
                vx_put(vp);
                kfree(ip, ump->um_malloctype);
                goto retry;
        }
        vp->v_data = ip;

        /* Read in the disk contents for the inode, copy into the inode. */
        error = bread(ump->um_devvp, fsbtodoff(fs, ino_to_fsba(fs, ino)),
            (int)fs->fs_bsize, &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().
                 */
                vp->v_type = VBAD;
                brelse(bp);
                vx_put(vp);
                *vpp = NULL;
                return (error);
        }
        ip->i_din = *((struct ufs1_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
        if (DOINGSOFTDEP(vp))
                softdep_load_inodeblock(ip);
        else
                ip->i_effnlink = ip->i_nlink;
        bqrelse(bp);

        /*
         * Initialize the vnode from the inode, check for aliases.
         * Note that the underlying vnode may have changed.
         */
        error = ufs_vinit(mp, &vp);
        if (error) {
                vp->v_type = VBAD;
                vx_put(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_gen == 0) {
                ip->i_gen = krandom() / 2 + 1;
                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_uid = ip->i_din.di_ouid;          /* XXX */
                ip->i_gid = ip->i_din.di_ogid;          /* XXX */
        }                                               /* XXX */

        /* 
         * return a VX locked and refd vnode (VX == same as normal vget()
         * vnode so we are ok)
         */
        vx_downgrade(vp);
        *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)
 * - check that the given client host has export rights and return
 *   those rights via. exflagsp and credanonp
 */
int
ffs_fhtovp(struct mount *mp, struct vnode *rootvp,
           struct fid *fhp, struct vnode **vpp)
{
        struct ufid *ufhp;
        struct fs *fs;

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

/*
 * Vnode pointer to File handle
 */
/* ARGSUSED */
int
ffs_vptofh(struct vnode *vp, struct fid *fhp)
{
        struct inode *ip;
        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_gen;
        return (0);
}

/*
 * Initialize the filesystem; just use ufs_init.
 */
static int
ffs_init(struct vfsconf *vfsp)
{
        softdep_initialize();
        kmalloc_raise_limit(M_FFSNODE, 0);
        return (ufs_init(vfsp));
}

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

        /*
         * First write back the summary information.
         *
         * NOTE: the getblk is relative to the device vnode so bio1
         * contains the device block number.
         */
        blks = howmany(fs->fs_cssize, fs->fs_fsize);
        space = 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, fsbtodoff(fs, fs->fs_csaddr + i),
                            size, 0, 0);
                bcopy(space, bp->b_data, (uint)size);
                space = (char *)space + size;
                if (waitfor != MNT_WAIT)
                        bawrite(bp);
                else if ((error = bwrite(bp)) != 0)
                        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, (int)fs->fs_sbsize, 0, 0);
        fs->fs_fmod = 0;
        fs->fs_time = time_second;
        bcopy((caddr_t)fs, bp->b_data, (uint)fs->fs_sbsize);
        /* Restore compatibility to old filesystems.               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)) != 0)
                allerror = error;
        return (allerror);
}