xnu-792.13.8.tar.gz

[apple/xnu.git] / bsd / ufs / ffs / ffs_vfsops.c

/*
 * Copyright (c) 2000-2004 Apple Computer, Inc. All rights reserved.
 *
 * @APPLE_LICENSE_OSREFERENCE_HEADER_START@
 * 
 * This file contains Original Code and/or Modifications of Original Code 
 * as defined in and that are subject to the Apple Public Source License 
 * Version 2.0 (the 'License'). You may not use this file except in 
 * compliance with the License.  The rights granted to you under the 
 * License may not be used to create, or enable the creation or 
 * redistribution of, unlawful or unlicensed copies of an Apple operating 
 * system, or to circumvent, violate, or enable the circumvention or 
 * violation of, any terms of an Apple operating system software license 
 * agreement.
 *
 * Please obtain a copy of the License at 
 * http://www.opensource.apple.com/apsl/ and read it before using this 
 * file.
 *
 * The Original Code and all software distributed under the License are 
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 
 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 
 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 
 * Please see the License for the specific language governing rights and 
 * limitations under the License.
 *
 * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
 */
/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
/*
 * 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        8.31 (Berkeley) 5/20/95
 */

#include <rev_endian_fs.h>
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/kauth.h>
#include <sys/kernel.h>
#include <sys/vnode_internal.h>
#include <sys/socket.h>
#include <sys/mount_internal.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/file.h>
#include <sys/disk.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/ubc.h>
#include <sys/quota.h>

#include <miscfs/specfs/specdev.h>

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

#include <ufs/ffs/fs.h>
#include <ufs/ffs/ffs_extern.h>
#if REV_ENDIAN_FS
#include <ufs/ufs/ufs_byte_order.h>
#include <libkern/OSByteOrder.h>
#endif /* REV_ENDIAN_FS */

int ffs_sbupdate(struct ufsmount *, int);

struct vfsops ufs_vfsops = {
        ffs_mount,
        ufs_start,
        ffs_unmount,
        ufs_root,
        ufs_quotactl,
        ffs_vfs_getattr,
        ffs_sync,
        ffs_vget,
        ffs_fhtovp,
        ffs_vptofh,
        ffs_init,
        ffs_sysctl,
        ffs_vfs_setattr,
        {0}
};

extern u_long nextgennumber;

union _qcvt {
        int64_t qcvt;
        int32_t val[2];
};
#define SETHIGH(q, h) { \
        union _qcvt tmp; \
        tmp.qcvt = (q); \
        tmp.val[_QUAD_HIGHWORD] = (h); \
        (q) = tmp.qcvt; \
}
#define SETLOW(q, l) { \
        union _qcvt tmp; \
        tmp.qcvt = (q); \
        tmp.val[_QUAD_LOWWORD] = (l); \
        (q) = tmp.qcvt; \
}

/*
 * Called by main() when ufs is going to be mounted as root.
 */
int
ffs_mountroot(mount_t mp, vnode_t rvp, vfs_context_t context)
{
        struct proc *p = current_proc();        /* XXX */
        int     error;
        
        /* Set asynchronous flag by default */
        vfs_setflags(mp, MNT_ASYNC);

        if (error = ffs_mountfs(rvp, mp, context))
                return (error);

        (void)ffs_statfs(mp, vfs_statfs(mp), NULL);

        return (0);
}

/*
 * VFS Operations.
 *
 * mount system call
 */
int
ffs_mount(struct mount *mp, vnode_t devvp, __unused user_addr_t data,  vfs_context_t context)
{
        struct proc *p = vfs_context_proc(context);
        struct ufsmount *ump;
        register struct fs *fs;
        u_int size;
        int error  = 0, flags;
        mode_t accessmode;
        int ronly;
        int reload = 0;

        /*
         * If updating, check whether changing from read-write to
         * read-only; if there is no device name, that's all we do.
         */
        if (mp->mnt_flag & MNT_UPDATE) {
                ump = VFSTOUFS(mp);
                fs = ump->um_fs;
                if (fs->fs_ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
                        /*
                         * Flush any dirty data.
                         */
                        VFS_SYNC(mp, MNT_WAIT, context);
                        /*
                         * Check for and optionally get rid of files open
                         * for writing.
                         */
                        flags = WRITECLOSE;
                        if (mp->mnt_flag & MNT_FORCE)
                                flags |= FORCECLOSE;
                        if (error = ffs_flushfiles(mp, flags, p))
                                return (error);
                        fs->fs_clean = 1;
                        fs->fs_ronly = 1;
                        if (error = ffs_sbupdate(ump, MNT_WAIT)) {
                                fs->fs_clean = 0;
                                fs->fs_ronly = 0;
                                return (error);
                        }
                }
                /* save fs_ronly to later use */
                ronly = fs->fs_ronly;
                if ((mp->mnt_flag & MNT_RELOAD) || ronly)
                        reload = 1;
                if ((reload) &&
                    (error = ffs_reload(mp, vfs_context_ucred(context), p)))
                        return (error);
                /* replace the ronly after load */
                fs->fs_ronly = ronly;
                /* 
                * Do not update the file system if the user was in singleuser
                * and then tries to mount -uw without fscking
                */
                if (!fs->fs_clean && ronly) {
                        printf("WARNING: trying to mount a dirty file system\n");
                        if (issingleuser() && (mp->mnt_flag & MNT_ROOTFS)) {
                                printf("WARNING: R/W mount of %s denied. Filesystem is not clean - run fsck\n",fs->fs_fsmnt);
                                /* 
                                 * Reset the readonly bit as reload might have
                                 * modified this bit 
                                 */
                                fs->fs_ronly = 1;
                                return(EPERM);
                        }
                }

                if (ronly && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
                        fs->fs_ronly = 0;
                        fs->fs_clean = 0;
                        (void) ffs_sbupdate(ump, MNT_WAIT);
                }
                if (devvp == 0) {
                        return(0);
                }
        }
        if ((mp->mnt_flag & MNT_UPDATE) == 0)
                error = ffs_mountfs(devvp, mp, context);
        else {
                if (devvp != ump->um_devvp)
                        error = EINVAL; /* needs translation */
        }
        if (error) {
                return (error);
        }
        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        bzero(fs->fs_fsmnt , sizeof(fs->fs_fsmnt));
        strncpy(fs->fs_fsmnt,  (caddr_t)mp->mnt_vfsstat.f_mntonname, sizeof(fs->fs_fsmnt) - 1); 
        (void)ffs_statfs(mp, &mp->mnt_vfsstat, p);
        return (0);
}


struct ffs_reload_cargs {
        struct vnode    *devvp;
        kauth_cred_t cred;
        struct fs       *fs;
        struct proc     *p;
        int             error;
#if REV_ENDIAN_FS
        int             rev_endian;
#endif /* REV_ENDIAN_FS */
};


static int
ffs_reload_callback(struct vnode *vp, void *cargs)
{
        struct inode *ip;
        struct buf   *bp;
        struct fs    *fs;
        struct ffs_reload_cargs *args;

        args = (struct ffs_reload_cargs *)cargs;

        /*
         * flush all the buffers associated with this node
         */
        if (buf_invalidateblks(vp, 0, 0, 0))
                panic("ffs_reload: dirty2");

        /*
         * Step 6: re-read inode data
         */
        ip = VTOI(vp);
        fs = args->fs;

        if (args->error = (int)buf_bread(args->devvp, (daddr64_t)((unsigned)fsbtodb(fs, ino_to_fsba(fs, ip->i_number))),
                                         (int)fs->fs_bsize, NOCRED, &bp)) {
                buf_brelse(bp);

                return (VNODE_RETURNED_DONE);
        }

#if REV_ENDIAN_FS
        if (args->rev_endian) {
                byte_swap_inode_in(((struct dinode *)buf_dataptr(bp) +
                                    ino_to_fsbo(fs, ip->i_number)), ip);
        } else {
#endif /* REV_ENDIAN_FS */
                ip->i_din = *((struct dinode *)buf_dataptr(bp) +
                              ino_to_fsbo(fs, ip->i_number));
#if REV_ENDIAN_FS
        }
#endif /* REV_ENDIAN_FS */

        buf_brelse(bp);

        return (VNODE_RETURNED);
}


/*
 * 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.
 */
ffs_reload(struct mount *mountp, kauth_cred_t cred, struct proc *p)
{
        register struct vnode *devvp;
        void *space;
        struct buf *bp;
        struct fs *fs, *newfs;
        int i, blks, size, error;
        u_int64_t maxfilesize;                                  /* XXX */
        int32_t *lp;
        struct ffs_reload_cargs args;
#if REV_ENDIAN_FS
        int rev_endian = (mountp->mnt_flag & MNT_REVEND);
#endif /* REV_ENDIAN_FS */

        if ((mountp->mnt_flag & MNT_RDONLY) == 0)
                return (EINVAL);
        /*
         * Step 1: invalidate all cached meta-data.
         */
        devvp = VFSTOUFS(mountp)->um_devvp;
        if (buf_invalidateblks(devvp, 0, 0, 0))
                panic("ffs_reload: dirty1");
        /*
         * Step 2: re-read superblock from disk.
         */
        size = vfs_devblocksize(mountp);

        if (error = (int)buf_bread(devvp, (daddr64_t)((unsigned)(SBOFF/size)), SBSIZE, NOCRED,&bp)) {
                buf_brelse(bp);
                return (error);
        }
        newfs = (struct fs *)buf_dataptr(bp);
#if REV_ENDIAN_FS
        if (rev_endian) {
                byte_swap_sbin(newfs);
        }
#endif /* REV_ENDIAN_FS */
        if (newfs->fs_magic != FS_MAGIC || newfs->fs_bsize > MAXBSIZE ||
            newfs->fs_bsize < sizeof(struct fs)) {
#if REV_ENDIAN_FS
                if (rev_endian)
                        byte_swap_sbout(newfs);
#endif /* REV_ENDIAN_FS */

                buf_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_contigdirs = fs->fs_contigdirs;
        bcopy(newfs, fs, (u_int)fs->fs_sbsize);
        if (fs->fs_sbsize < SBSIZE)
                buf_markinvalid(bp);
#if REV_ENDIAN_FS
        if (rev_endian)
                byte_swap_sbout(newfs);
#endif /* REV_ENDIAN_FS */
        buf_brelse(bp);
        mountp->mnt_maxsymlinklen = fs->fs_maxsymlinklen;
        ffs_oldfscompat(fs);
        maxfilesize = 0x100000000ULL;    /* 4GB */
        if (fs->fs_maxfilesize > maxfilesize)                   /* XXX */
                fs->fs_maxfilesize = maxfilesize;               /* 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;
                if (error = (int)buf_bread(devvp, (daddr64_t)((unsigned)fsbtodb(fs, fs->fs_csaddr + i)), size,
                                           NOCRED, &bp)) {
                        buf_brelse(bp);
                        return (error);
                }
#if REV_ENDIAN_FS
                if (rev_endian) {
                        /* csum swaps */
                        byte_swap_ints((int *)buf_dataptr(bp), size / sizeof(int));
                }
#endif /* REV_ENDIAN_FS */
                bcopy((char *)buf_dataptr(bp), space, (u_int)size);
#if REV_ENDIAN_FS
                if (rev_endian) {
                        /* csum swaps */
                        byte_swap_ints((int *)buf_dataptr(bp), size / sizeof(int));
                }
#endif /* REV_ENDIAN_FS */
                space = (char *) space + size;
                buf_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;
        }
#if REV_ENDIAN_FS
        args.rev_endian = rev_endian;
#endif /* REV_ENDIAN_FS */
        args.devvp = devvp;
        args.cred = cred;
        args.fs = fs;
        args.p = p;
        args.error = 0;
        /*
         * ffs_reload_callback will be called for each vnode
         * hung off of this mount point that can't be recycled...
         * vnode_iterate will recycle those that it can (the VNODE_RELOAD option)
         * the vnode will be in an 'unbusy' state (VNODE_WAIT) and 
         * properly referenced and unreferenced around the callback
         */
        vnode_iterate(mountp, VNODE_RELOAD | VNODE_WAIT, ffs_reload_callback, (void *)&args);

        return (args.error);
}

/*
 * Common code for mount and mountroot
 */
int
ffs_mountfs(devvp, mp, context)
        struct vnode *devvp;
        struct mount *mp;
        vfs_context_t context;
{
        struct ufsmount *ump;
        struct buf *bp;
        struct fs *fs;
        dev_t dev;
        struct buf *cgbp;
        struct cg *cgp;
        int32_t clustersumoff;
        void *space;
        int error, i, blks, ronly;
        u_int32_t size;
        int32_t *lp;
        kauth_cred_t cred;
        u_int64_t maxfilesize;                                  /* XXX */
        u_int dbsize = DEV_BSIZE;
#if REV_ENDIAN_FS
        int rev_endian=0;
#endif /* REV_ENDIAN_FS */
        dev = devvp->v_rdev;
        cred = vfs_context_ucred(context);

        ronly = vfs_isrdonly(mp);
        bp  = NULL;
        ump = NULL;

        /* Advisory locking should be handled at the VFS layer */
        vfs_setlocklocal(mp);

        /* Obtain the actual device block size */
        if (VNOP_IOCTL(devvp, DKIOCGETBLOCKSIZE, (caddr_t)&size, 0, context)) {
                error = ENXIO;
                goto out;
        }

        if (error = (int)buf_bread(devvp, (daddr64_t)((unsigned)(SBOFF/size)),
            SBSIZE, cred, &bp))
                goto out;
        fs = (struct fs *)buf_dataptr(bp);
#if REV_ENDIAN_FS
        if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE ||
            fs->fs_bsize < sizeof(struct fs)) {
                int magic = fs->fs_magic;
                
                byte_swap_ints(&magic, 1);
                if (magic != FS_MAGIC) {
                        error = EINVAL;
                        goto out;
                }
                byte_swap_sbin(fs);
                if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE ||
                        fs->fs_bsize < sizeof(struct fs)) {
                        byte_swap_sbout(fs);
                        error = EINVAL;         /* XXX needs translation */
                        goto out;
                }
                rev_endian=1;
        }
#endif /* REV_ENDIAN_FS */
        if (fs->fs_magic != FS_MAGIC || fs->fs_bsize > MAXBSIZE ||
            fs->fs_bsize < sizeof(struct fs)) {
#if REV_ENDIAN_FS
                if (rev_endian)
                        byte_swap_sbout(fs);
#endif /* REV_ENDIAN_FS */
                error = EINVAL;         /* XXX needs translation */
                goto out;
        }


        /*
         * Buffer cache does not handle multiple pages in a buf when
         * invalidating incore buffer in pageout. There are no locks 
         * in the pageout path.  So there is a danger of loosing data when
         * block allocation happens at the same time a pageout of buddy
         * page occurs. incore() returns buf with both
         * pages, this leads vnode-pageout to incorrectly flush of entire. 
         * buf. Till the low level ffs code is modified to deal with these
         * do not mount any FS more than 4K size.
         */
        /*
         * Can't mount filesystems with a fragment size less than DIRBLKSIZ
         */
        /*
         * Don't mount dirty filesystems, except for the root filesystem
         */
        if ((fs->fs_bsize > PAGE_SIZE) || (fs->fs_fsize < DIRBLKSIZ) ||
        ((!(mp->mnt_flag & MNT_ROOTFS)) && (!fs->fs_clean))) {
#if REV_ENDIAN_FS
                if (rev_endian)
                        byte_swap_sbout(fs);
#endif /* REV_ENDIAN_FS */
        error = ENOTSUP;
        goto out;
    }
         
        /* Let's figure out the devblock size the file system is with */
        /* the device block size = fragment size / number of sectors per frag */

        dbsize = fs->fs_fsize / NSPF(fs);
        if(dbsize <= 0 ) {
                kprintf("device blocksize computaion failed\n");
        } else {
                if (VNOP_IOCTL(devvp, DKIOCSETBLOCKSIZE, (caddr_t)&dbsize,
                                FWRITE, context) != 0) {  
                        kprintf("failed to set device blocksize\n");
                }  
                /* force the specfs to reread blocksize from size() */
                set_fsblocksize(devvp);
        } 

        /* XXX updating 4.2 FFS superblocks trashes rotational layout tables */
        if (fs->fs_postblformat == FS_42POSTBLFMT && !ronly) {
#if REV_ENDIAN_FS
                if (rev_endian)
                        byte_swap_sbout(fs);
#endif /* REV_ENDIAN_FS */
                error = EROFS;          /* needs translation */
                goto out;
        }

        /* If we are not mounting read only, then check for overlap 
         * condition in cylinder group's free block map.
         * If overlap exists, then force this into a read only mount
         * to avoid further corruption. PR#2216969
         */
        if (ronly == 0){
            if (error = (int)buf_bread (devvp, (daddr64_t)((unsigned)fsbtodb(fs, cgtod(fs, 0))),
                                        (int)fs->fs_cgsize, NOCRED, &cgbp)) {
                        buf_brelse(cgbp);
                        goto out;
                }
                cgp = (struct cg *)buf_dataptr(cgbp);
#if REV_ENDIAN_FS
                if (rev_endian)
                        byte_swap_cgin(cgp,fs);
#endif /* REV_ENDIAN_FS */
                if (!cg_chkmagic(cgp)){
#if REV_ENDIAN_FS
                                if (rev_endian)
                                        byte_swap_cgout(cgp,fs);
#endif /* REV_ENDIAN_FS */
                        buf_brelse(cgbp);
                        goto out;
                }
                if (cgp->cg_clustersumoff != 0) {
                        /* Check for overlap */
                        clustersumoff = cgp->cg_freeoff +
                        howmany(fs->fs_cpg * fs->fs_spc / NSPF(fs), NBBY);
                        clustersumoff = roundup(clustersumoff, sizeof(long));
                        if (cgp->cg_clustersumoff < clustersumoff) {
                        /* Overlap exists */
                        mp->mnt_flag |= MNT_RDONLY;
                                ronly = 1;
                        }
                }
#if REV_ENDIAN_FS
                        if (rev_endian)
                                byte_swap_cgout(cgp,fs);
#endif /* REV_ENDIAN_FS */
                        buf_brelse(cgbp);
        }

        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((char *)buf_dataptr(bp), ump->um_fs, (u_int)fs->fs_sbsize);
        if (fs->fs_sbsize < SBSIZE)
                buf_markinvalid(bp);
#if REV_ENDIAN_FS
        if (rev_endian)
                byte_swap_sbout(fs);
#endif /* REV_ENDIAN_FS */
        buf_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(u_int8_t);
        space = _MALLOC((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 = (int)buf_bread(devvp, (daddr64_t)((unsigned)fsbtodb(fs, fs->fs_csaddr + i)),
                                           size, cred, &bp)) {
                        _FREE(fs->fs_csp, M_UFSMNT);
                        goto out;
                }
                bcopy((char *)buf_dataptr(bp), space, (u_int)size);
#if REV_ENDIAN_FS
                if (rev_endian)
                        byte_swap_ints((int *) space, size / sizeof(int));
#endif /* REV_ENDIAN_FS */
                space = (char *)space + size;
                buf_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(u_int8_t);
        fs->fs_contigdirs = (u_int8_t *)space;
        space = (u_int8_t *)space + size;
        bzero(fs->fs_contigdirs, size);
        /* XXX Compatibility for old filesystems */
        if (fs->fs_avgfilesize <= 0)
                fs->fs_avgfilesize = AVFILESIZ;
        if (fs->fs_avgfpdir <= 0)
                fs->fs_avgfpdir = AFPDIR;
        /* XXX End of compatibility */
        mp->mnt_data = (qaddr_t)ump;
        mp->mnt_vfsstat.f_fsid.val[0] = (long)dev;
        mp->mnt_vfsstat.f_fsid.val[1] = vfs_typenum(mp);
        /* XXX warning hardcoded max symlen and not "mp->mnt_maxsymlinklen = fs->fs_maxsymlinklen;" */
        mp->mnt_maxsymlinklen = 60;
#if REV_ENDIAN_FS
        if (rev_endian)
                mp->mnt_flag |= MNT_REVEND;
#endif /* REV_ENDIAN_FS */
        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++)
                dqfileinit(&ump->um_qfiles[i]);
        ffs_oldfscompat(fs);
        ump->um_savedmaxfilesize = fs->fs_maxfilesize;          /* XXX */
        maxfilesize = 0x100000000ULL;    /* 4GB */
#if 0
        maxfilesize = (u_int64_t)0x40000000 * fs->fs_bsize - 1; /* XXX */
#endif /* 0 */
        if (fs->fs_maxfilesize > maxfilesize)                   /* XXX */
                fs->fs_maxfilesize = maxfilesize;               /* XXX */
        if (ronly == 0) {
                fs->fs_clean = 0;
                (void) ffs_sbupdate(ump, MNT_WAIT);
        }
        return (0);
out:
        if (bp)
                buf_brelse(bp);
        if (ump) {
                _FREE(ump->um_fs, M_UFSMNT);
                _FREE(ump, M_UFSMNT);
        }
        return (error);
}

/*
 * Sanity checks for old file systems.
 *
 * XXX - goes away some day.
 */
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 */
        return (0);
}

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

        flags = 0;
        force = 0;
        if (mntflags & MNT_FORCE) {
                flags |= FORCECLOSE;
                force = 1;
        }
        if ( (error = ffs_flushfiles(mp, flags, p)) && !force )
                return (error);
        ump = VFSTOUFS(mp);
        fs = ump->um_fs;

        if (fs->fs_ronly == 0) {
                fs->fs_clean = 1;
                if (error = ffs_sbupdate(ump, MNT_WAIT)) {
                        fs->fs_clean = 0;
#ifdef notyet
                /* we can atleast cleanup ; as the media could be WP */
                /* & during mount, we do not check for write failures  */
                /* FIXME LATER : the Correct fix would be to have */
                /* mount detect the WP media and downgrade to readonly mount */
                /* For now, here it is */
                        return (error);
#endif /* notyet */
                }
        }
        _FREE(fs->fs_csp, M_UFSMNT);
        _FREE(fs, M_UFSMNT);
        _FREE(ump, M_UFSMNT);

        return (0);
}

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

        ump = VFSTOUFS(mp);

#if QUOTA
        /*
         * NOTE: The open quota files have an indirect reference
         * on the root directory vnode.  We must account for this
         * extra reference when doing the intial vflush.
         */
        if (mp->mnt_flag & MNT_QUOTA) {
                struct vnode *rootvp = NULLVP;
                int quotafilecnt = 0;

                /* Find out how many quota files we have open. */
                for (i = 0; i < MAXQUOTAS; i++) {
                        if (ump->um_qfiles[i].qf_vp != NULLVP)
                                ++quotafilecnt;
                }

                /*
                 * Check if the root vnode is in our inode hash
                 * (so we can skip over it).
                 */
                rootvp = ufs_ihashget(ump->um_dev, ROOTINO);

                error = vflush(mp, rootvp, SKIPSYSTEM|flags);

                if (rootvp) {
                        /*
                         * See if there are additional references on the
                         * root vp besides the ones obtained from the open
                         * quota files and the hfs_chashget call above.
                         */
                        if ((error == 0) &&
                            (rootvp->v_usecount > (1 + quotafilecnt))) {
                                error = EBUSY;  /* root dir is still open */
                        }
                        vnode_put(rootvp);
                }
                if (error && (flags & FORCECLOSE) == 0)
                        return (error);

                for (i = 0; i < MAXQUOTAS; i++) {
                        if (ump->um_qfiles[i].qf_vp == NULLVP)
                                continue;
                        quotaoff(mp, i);
                }
                /*
                 * Here we fall through to vflush again to ensure
                 * that we have gotten rid of all the system vnodes.
                 */
        }
#endif
        error = vflush(mp, NULLVP, SKIPSWAP|flags);
        error = vflush(mp, NULLVP, flags);
        return (error);
}

/*
 * Get file system statistics.
 */
int
ffs_statfs(mp, sbp, context)
        struct mount *mp;
        register struct vfsstatfs *sbp;
        vfs_context_t context;
{
        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 = (uint64_t)((unsigned long)fs->fs_dsize);
        sbp->f_bfree = (uint64_t) ((unsigned long)(fs->fs_cstotal.cs_nbfree * fs->fs_frag +
                fs->fs_cstotal.cs_nffree));
        sbp->f_bavail = (uint64_t) ((unsigned long)freespace(fs, fs->fs_minfree));
        sbp->f_files =  (uint64_t) ((unsigned long)(fs->fs_ncg * fs->fs_ipg - ROOTINO));
        sbp->f_ffree = (uint64_t) ((unsigned long)fs->fs_cstotal.cs_nifree);
        return (0);
}

int
ffs_vfs_getattr(mp, fsap, context)
        struct mount *mp;
        struct vfs_attr *fsap;
        vfs_context_t context;
{
        struct ufsmount *ump;
        struct fs *fs;
        kauth_cred_t cred;
        struct vnode *devvp;
        struct buf *bp;
        struct ufslabel *ulp;
        char *offset;
        int bs, error, length;

        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        cred = vfs_context_ucred(context);

        VFSATTR_RETURN(fsap, f_bsize, fs->fs_fsize);
        VFSATTR_RETURN(fsap, f_iosize, fs->fs_bsize);
        VFSATTR_RETURN(fsap, f_blocks, (uint64_t)((unsigned long)fs->fs_dsize));
        VFSATTR_RETURN(fsap, f_bfree, (uint64_t)((unsigned long)
            (fs->fs_cstotal.cs_nbfree * fs->fs_frag +
            fs->fs_cstotal.cs_nffree)));
        VFSATTR_RETURN(fsap, f_bavail, (uint64_t)((unsigned long)freespace(fs,
            fs->fs_minfree)));
        VFSATTR_RETURN(fsap, f_files, (uint64_t)((unsigned long)
            (fs->fs_ncg * fs->fs_ipg - ROOTINO)));
        VFSATTR_RETURN(fsap, f_ffree, (uint64_t)((unsigned long)
            fs->fs_cstotal.cs_nifree));

        if (VFSATTR_IS_ACTIVE(fsap, f_fsid)) {
                fsap->f_fsid.val[0] = mp->mnt_vfsstat.f_fsid.val[0];
                fsap->f_fsid.val[1] = mp->mnt_vfsstat.f_fsid.val[1];
                VFSATTR_SET_SUPPORTED(fsap, f_fsid);
        }

        if (VFSATTR_IS_ACTIVE(fsap, f_vol_name)) {
                devvp = ump->um_devvp;
                bs = vfs_devblocksize(mp);

                if (error = (int)buf_meta_bread(devvp,
                    (daddr64_t)(UFS_LABEL_OFFSET / bs),
                    MAX(bs, UFS_LABEL_SIZE), cred, &bp)) {
                        if (bp)
                                buf_brelse(bp);
                        return (error);
                }

                /*
                 * Since the disklabel is read directly by older user space
                 * code, make sure this buffer won't remain in the cache when
                 * we release it.
                 */
                buf_setflags(bp, B_NOCACHE);

                offset = buf_dataptr(bp) + (UFS_LABEL_OFFSET % bs);
                ulp = (struct ufslabel *)offset;

                if (ufs_label_check(ulp)) {
                        length = ulp->ul_namelen;
#if REV_ENDIAN_FS
                        if (mp->mnt_flag & MNT_REVEND)
                                length = OSSwapInt16(length);
#endif
                        if (length > 0 && length <= UFS_MAX_LABEL_NAME) {
                                bcopy(ulp->ul_name, fsap->f_vol_name, length);
                                fsap->f_vol_name[UFS_MAX_LABEL_NAME - 1] = '\0';
                                fsap->f_vol_name[length] = '\0';
                        }
                }

                buf_brelse(bp);
                VFSATTR_SET_SUPPORTED(fsap, f_vol_name);
        }

        if (VFSATTR_IS_ACTIVE(fsap, f_capabilities)) {
                fsap->f_capabilities.capabilities[VOL_CAPABILITIES_FORMAT] =
                    VOL_CAP_FMT_SYMBOLICLINKS |
                    VOL_CAP_FMT_HARDLINKS |
                    VOL_CAP_FMT_SPARSE_FILES |
                    VOL_CAP_FMT_CASE_SENSITIVE |
                    VOL_CAP_FMT_CASE_PRESERVING |
                    VOL_CAP_FMT_FAST_STATFS ;
                fsap->f_capabilities.capabilities[VOL_CAPABILITIES_INTERFACES]
                    = VOL_CAP_INT_NFSEXPORT |
                    VOL_CAP_INT_VOL_RENAME |
                    VOL_CAP_INT_ADVLOCK |
                    VOL_CAP_INT_FLOCK;
                fsap->f_capabilities.capabilities[VOL_CAPABILITIES_RESERVED1]
                    = 0;
                fsap->f_capabilities.capabilities[VOL_CAPABILITIES_RESERVED2]
                    = 0;

                /* Capabilities we know about: */
                fsap->f_capabilities.valid[VOL_CAPABILITIES_FORMAT] =
                    VOL_CAP_FMT_PERSISTENTOBJECTIDS |
                    VOL_CAP_FMT_SYMBOLICLINKS |
                    VOL_CAP_FMT_HARDLINKS |
                    VOL_CAP_FMT_JOURNAL |
                    VOL_CAP_FMT_JOURNAL_ACTIVE |
                    VOL_CAP_FMT_NO_ROOT_TIMES |
                    VOL_CAP_FMT_SPARSE_FILES |
                    VOL_CAP_FMT_ZERO_RUNS |
                    VOL_CAP_FMT_CASE_SENSITIVE |
                    VOL_CAP_FMT_CASE_PRESERVING |
                    VOL_CAP_FMT_FAST_STATFS |
                    VOL_CAP_FMT_2TB_FILESIZE;
                fsap->f_capabilities.valid[VOL_CAPABILITIES_INTERFACES] =
                    VOL_CAP_INT_SEARCHFS |
                    VOL_CAP_INT_ATTRLIST |
                    VOL_CAP_INT_NFSEXPORT |
                    VOL_CAP_INT_READDIRATTR |
                    VOL_CAP_INT_EXCHANGEDATA |
                    VOL_CAP_INT_COPYFILE |
                    VOL_CAP_INT_ALLOCATE |
                    VOL_CAP_INT_VOL_RENAME |
                    VOL_CAP_INT_ADVLOCK |
                    VOL_CAP_INT_FLOCK ;
                fsap->f_capabilities.valid[VOL_CAPABILITIES_RESERVED1] = 0;
                fsap->f_capabilities.valid[VOL_CAPABILITIES_RESERVED2] = 0;

                VFSATTR_SET_SUPPORTED(fsap, f_capabilities);
        }

        if (VFSATTR_IS_ACTIVE(fsap, f_attributes)) {
                fsap->f_attributes.validattr.commonattr = 0;
                fsap->f_attributes.validattr.volattr =
                    ATTR_VOL_NAME | ATTR_VOL_CAPABILITIES | ATTR_VOL_ATTRIBUTES;
                fsap->f_attributes.validattr.dirattr = 0;
                fsap->f_attributes.validattr.fileattr = 0;
                fsap->f_attributes.validattr.forkattr = 0;

                fsap->f_attributes.nativeattr.commonattr = 0;
                fsap->f_attributes.nativeattr.volattr =
                    ATTR_VOL_NAME | ATTR_VOL_CAPABILITIES | ATTR_VOL_ATTRIBUTES;
                fsap->f_attributes.nativeattr.dirattr = 0;
                fsap->f_attributes.nativeattr.fileattr = 0;
                fsap->f_attributes.nativeattr.forkattr = 0;

                VFSATTR_SET_SUPPORTED(fsap, f_attributes);
        }

        return (0);
}


int
ffs_vfs_setattr(mp, fsap, context)
        struct mount *mp;
        struct vfs_attr *fsap;
        vfs_context_t context;
{
        struct ufsmount *ump;
        struct vnode *devvp;
        struct buf *bp;
        struct ufslabel *ulp;
        kauth_cred_t cred;
        char *offset;
        int bs, error;


        ump = VFSTOUFS(mp);
        cred = vfs_context_ucred(context);

        if (VFSATTR_IS_ACTIVE(fsap, f_vol_name)) {
                devvp = ump->um_devvp;
                bs = vfs_devblocksize(mp);
                if (error = buf_meta_bread(devvp,
                    (daddr64_t)(UFS_LABEL_OFFSET / bs),
                    MAX(bs, UFS_LABEL_SIZE), cred, &bp)) {
                        if (bp)
                                buf_brelse(bp);
                        return (error);
                }

                /*
                 * Since the disklabel is read directly by older user space
                 * code, make sure this buffer won't remain in the cache when
                 * we release it.
                 */
                buf_setflags(bp, B_NOCACHE);

                /* Validate the label structure; init if not valid */
                offset = buf_dataptr(bp) + (UFS_LABEL_OFFSET % bs);
                ulp = (struct ufslabel *)offset;
                if (!ufs_label_check(ulp))
                        ufs_label_init(ulp);

                /* Copy new name over existing name */
                ulp->ul_namelen = strlen(fsap->f_vol_name);
                bcopy(fsap->f_vol_name, ulp->ul_name, ulp->ul_namelen);
                ulp->ul_name[UFS_MAX_LABEL_NAME - 1] = '\0';
                ulp->ul_name[ulp->ul_namelen] = '\0';

#if REV_ENDIAN_FS
                if (mp->mnt_flag & MNT_REVEND)
                        ulp->ul_namelen = OSSwapInt16(ulp->ul_namelen);
#endif

                /* Update the checksum */
                ulp->ul_checksum = 0;
                ulp->ul_checksum = ul_cksum(ulp, sizeof(*ulp));

                /* Write the label back to disk */
                buf_bwrite(bp);
                bp = NULL;

                VFSATTR_SET_SUPPORTED(fsap, f_vol_name);
        }

        return (0);
 }
struct ffs_sync_cargs {
        vfs_context_t context;
        int    waitfor;
        int    error;
};


static int
ffs_sync_callback(struct vnode *vp, void *cargs)
{
        struct inode *ip;
        struct ffs_sync_cargs *args;
        int error;

        args = (struct ffs_sync_cargs *)cargs;

        ip = VTOI(vp);

        if ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) || vnode_hasdirtyblks(vp)) {
                error = VNOP_FSYNC(vp, args->waitfor, args->context);

                if (error)
                        args->error = error;

        }
        return (VNODE_RETURNED);
}

/*
 * 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, context)
        struct mount *mp;
        int waitfor;
        vfs_context_t context;
{
        struct vnode *nvp, *vp;
        struct ufsmount *ump = VFSTOUFS(mp);
        struct fs *fs;
        struct timeval tv;
        int error, allerror = 0;
        struct ffs_sync_cargs args;

        fs = ump->um_fs;
        if (fs->fs_fmod != 0 && fs->fs_ronly != 0) {            /* XXX */
                printf("fs = %s\n", fs->fs_fsmnt);
                panic("update: rofs mod");
        }
        /*
         * Write back each (modified) inode.
         */
        args.context = context;
        args.waitfor = waitfor;
        args.error = 0;
        /*
         * ffs_sync_callback will be called for each vnode
         * hung off of this mount point... the vnode will be
         * properly referenced and unreferenced around the callback
         */
        vnode_iterate(mp, 0, ffs_sync_callback, (void *)&args);

        if (args.error)
                allerror = args.error;

        /*
         * Force stale file system control information to be flushed.
         */
        if (error = VNOP_FSYNC(ump->um_devvp, waitfor, context))
                allerror = error;
#if QUOTA
        qsync(mp);
#endif
        /*
         * Write back modified superblock.
         */
        if (fs->fs_fmod != 0) {
                fs->fs_fmod = 0;
                microtime(&tv);
                fs->fs_time = tv.tv_sec;
                if (error = ffs_sbupdate(ump, waitfor))
                        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, context)
        mount_t mp;
        ino64_t ino;
        vnode_t *vpp;
        vfs_context_t context;
{
        return(ffs_vget_internal(mp, (ino_t)ino, vpp, NULL, NULL, 0, 0));
}


int
ffs_vget_internal(mp, ino, vpp, dvp, cnp, mode, fhwanted)
        mount_t mp;
        ino_t   ino;
        vnode_t *vpp;
        vnode_t dvp;
        struct  componentname *cnp;
        int     mode;
        int     fhwanted;
{
        struct proc *p = current_proc();                /* XXX */
        struct fs *fs;
        struct inode *ip;
        struct ufsmount *ump;
        struct buf *bp;
        struct vnode *vp;
        struct vnode_fsparam vfsp;
        struct timeval tv;
        enum vtype vtype;
        dev_t dev;
        int i, type, error = 0;

        *vpp = NULL;
        ump  = VFSTOUFS(mp);
        dev  = ump->um_dev;
#if 0
        /* Check for unmount in progress */
        if (mp->mnt_kern_flag & MNTK_UNMOUNT) {
                return (EPERM);
        }
#endif
        /*
         * Allocate a new inode... do it before we check the
         * cache, because the MALLOC_ZONE may block
         */
        type = M_FFSNODE;
        MALLOC_ZONE(ip, struct inode *, sizeof(struct inode), type, M_WAITOK);

        /*
         * check in the inode hash
         */
        if ((*vpp = ufs_ihashget(dev, ino)) != NULL) {
               /*
                * found it... get rid of the allocation
                * that we didn't need and return
                * the 'found' vnode
                */
                FREE_ZONE(ip, sizeof(struct inode), type);
                vp = *vpp;
                return (0);
        }
        bzero((caddr_t)ip, sizeof(struct inode));
        /*
         * lock the inode
         */
//      lockinit(&ip->i_lock, PINOD, "inode", 0, 0);
//      lockmgr(&ip->i_lock, LK_EXCLUSIVE, (struct slock *)0, p);

        ip->i_fs = fs = ump->um_fs;
        ip->i_dev = dev;
        ip->i_number = ino;
#if QUOTA
        for (i = 0; i < MAXQUOTAS; i++)
                ip->i_dquot[i] = NODQUOT;
#endif
        SET(ip->i_flag, IN_ALLOC);
        /*
         * Put it onto its hash chain locked 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.
         */
        ufs_ihashins(ip);

        /* Read in the disk contents for the inode, copy into the inode. */
        if (error = (int)buf_bread(ump->um_devvp, (daddr64_t)((unsigned)fsbtodb(fs, ino_to_fsba(fs, ino))),
                                   (int)fs->fs_bsize, NOCRED, &bp)) {
                buf_brelse(bp);
                goto errout;
        }
#if REV_ENDIAN_FS
        if (mp->mnt_flag & MNT_REVEND) {
                byte_swap_inode_in(((struct dinode *)buf_dataptr(bp) + ino_to_fsbo(fs, ino)),ip);
        } else {
                ip->i_din = *((struct dinode *)buf_dataptr(bp) + ino_to_fsbo(fs, ino));
        }
#else
        ip->i_din = *((struct dinode *)buf_dataptr(bp) + ino_to_fsbo(fs, ino));
#endif /* REV_ENDIAN_FS */
        buf_brelse(bp);

        if (mode == 0)
                vtype = IFTOVT(ip->i_mode);
        else
                vtype = IFTOVT(mode);

        if (vtype == VNON) {
                if (fhwanted) {
                        /* NFS is in play */
                        error = ESTALE;
                        goto errout;
                } else {
                        error = ENOENT;
                        goto errout;
                }
        }

        vfsp.vnfs_mp = mp;
        vfsp.vnfs_vtype = vtype;
        vfsp.vnfs_str = "ufs";
        vfsp.vnfs_dvp = dvp;
        vfsp.vnfs_fsnode = ip;
        vfsp.vnfs_cnp = cnp;

        if (mode == 0)
                vfsp.vnfs_filesize = ip->i_din.di_size;
        else
                vfsp.vnfs_filesize = 0;

        if (vtype == VFIFO )
                vfsp.vnfs_vops = FFS_FIFOOPS;
        else if (vtype == VBLK || vtype == VCHR)
                vfsp.vnfs_vops = ffs_specop_p;
        else
                vfsp.vnfs_vops = ffs_vnodeop_p;
                
        if (vtype == VBLK || vtype == VCHR)
                vfsp.vnfs_rdev = ip->i_rdev;
        else
                vfsp.vnfs_rdev = 0;

        if (dvp && cnp && (cnp->cn_flags & MAKEENTRY))
                vfsp.vnfs_flags = 0;
        else
                vfsp.vnfs_flags = VNFS_NOCACHE;

        /*
         * Tag root directory
         */
        vfsp.vnfs_markroot = (ip->i_number == ROOTINO);
        vfsp.vnfs_marksystem = 0;

        if ((error = vnode_create(VNCREATE_FLAVOR, VCREATESIZE, &vfsp, &vp)))
                goto errout;

        /*
         * Finish inode initialization now that aliasing has been resolved.
         */
        ip->i_devvp = ump->um_devvp;
        ip->i_vnode = vp;

        vnode_ref(ip->i_devvp);
        vnode_addfsref(vp);
        vnode_settag(vp, VT_UFS);

        /*
         * Initialize modrev times
         */
        microtime(&tv);
        SETHIGH(ip->i_modrev, tv.tv_sec);
        SETLOW(ip->i_modrev, tv.tv_usec * 4294);

        /*
         * 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) {
                if (++nextgennumber < (u_long)tv.tv_sec)
                        nextgennumber = tv.tv_sec;
                ip->i_gen = nextgennumber;
                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 */
        *vpp = vp;

        CLR(ip->i_flag, IN_ALLOC);

        if (ISSET(ip->i_flag, IN_WALLOC))
                wakeup(ip);

        return (0);

errout:
        ufs_ihashrem(ip);

        if (ISSET(ip->i_flag, IN_WALLOC))
                wakeup(ip);
        FREE_ZONE(ip, sizeof(struct inode), type);

        return (error);
}

/*
 * File handle to vnode
 *
 * Have to be really careful about stale file handles:
 * - check that the inode number is valid
 * - call vget to get the locked inode
 * - check for an unallocated inode (i_mode == 0)
 */
int
ffs_fhtovp(mp, fhlen, fhp, vpp, context)
        register struct mount *mp;
        int fhlen;
        unsigned char *fhp;
        struct vnode **vpp;
        vfs_context_t context;
{
        register struct ufid *ufhp;
        register struct inode *ip;
        struct vnode *nvp;
        struct fs *fs;
        int error;
        ino_t     ino;

        if (fhlen < (int)sizeof(struct ufid))
                return (EINVAL);
        ufhp = (struct ufid *)fhp;
        fs = VFSTOUFS(mp)->um_fs;
        ino = ntohl(ufhp->ufid_ino);
        if (ino < ROOTINO || ino >= fs->fs_ncg * fs->fs_ipg)
                return (ESTALE);
        error = ffs_vget_internal(mp, ino, &nvp, NULL, NULL, 0, 1);
        if (error) {
                *vpp = NULLVP;
                return (error);
        }
        ip = VTOI(nvp);
        if (ip->i_mode == 0 || ip->i_gen != ntohl(ufhp->ufid_gen)) {
                vnode_put(nvp);
                *vpp = NULLVP;
                return (ESTALE);
        }
        *vpp = nvp;
        return (0);
}

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

        if (*fhlenp < (int)sizeof(struct ufid))
                return (EOVERFLOW);
        ip = VTOI(vp);
        ufhp = (struct ufid *)fhp;
        ufhp->ufid_ino = htonl(ip->i_number);
        ufhp->ufid_gen = htonl(ip->i_gen);
        *fhlenp = sizeof(struct ufid);
        return (0);
}

/*
 * Initialize the filesystem; just use ufs_init.
 */
int
ffs_init(vfsp)
        struct vfsconf *vfsp;
{

        return (ufs_init(vfsp));
}

/*
 * fast filesystem related variables.
 */
ffs_sysctl(int *name, u_int namelen, user_addr_t oldp, size_t *oldlenp, 
                   user_addr_t newp, size_t newlen, vfs_context_t context)
{
        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 (ENOTSUP);
        }
        /* NOTREACHED */
}

/*
 * 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;
        void *space;
        int i, size, error, allerror = 0;
        int devBlockSize=0;
#if REV_ENDIAN_FS
        int rev_endian=(mp->um_mountp->mnt_flag & MNT_REVEND);
#endif /* REV_ENDIAN_FS */

        /*
         * First write back the summary information.
         */
        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 = buf_getblk(mp->um_devvp, (daddr64_t)((unsigned)fsbtodb(fs, fs->fs_csaddr + i)),
                                size, 0, 0, BLK_META);
                bcopy(space, (char *)buf_dataptr(bp), (u_int)size);
#if REV_ENDIAN_FS
                if (rev_endian) {
                        byte_swap_ints((int *)buf_dataptr(bp), size / sizeof(int));
                }
#endif /* REV_ENDIAN_FS */
                space = (char *)space + size;
                if (waitfor != MNT_WAIT)
                        buf_bawrite(bp);
                else if (error = (int)buf_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);
        devBlockSize = vfs_devblocksize(mp->um_mountp);

        bp = buf_getblk(mp->um_devvp, (daddr64_t)((unsigned)(SBOFF/devBlockSize)), (int)fs->fs_sbsize, 0, 0, BLK_META);
        bcopy((caddr_t)fs, (char *)buf_dataptr(bp), (u_int)fs->fs_sbsize);
        /* Restore compatibility to old file systems.              XXX */
        dfs = (struct fs *)buf_dataptr(bp);                     /* XXX */
        if (fs->fs_postblformat == FS_42POSTBLFMT)              /* XXX */
                dfs->fs_nrpos = -1;                             /* XXX */
#if REV_ENDIAN_FS
        /*  
        *  Swapping bytes here ; so that in case
        *   of inode format < FS_44INODEFMT appropriate
        *   fields get moved 
        */
        if (rev_endian) {
                byte_swap_sbout((struct fs *)buf_dataptr(bp));
        }
#endif /* REV_ENDIAN_FS */
        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 */
#if REV_ENDIAN_FS
        /* Note that dfs is already swapped so swap the filesize
        *  before writing
        */
        if (rev_endian) {
                dfs->fs_maxfilesize = OSSwapInt64(mp->um_savedmaxfilesize);             /* XXX */
        } else {
#endif /* REV_ENDIAN_FS */
                dfs->fs_maxfilesize = mp->um_savedmaxfilesize;  /* XXX */
#if REV_ENDIAN_FS
        }
#endif /* REV_ENDIAN_FS */
        if (waitfor != MNT_WAIT)
                buf_bawrite(bp);
        else if (error = (int)buf_bwrite(bp))
                allerror = error;

        return (allerror);
}