/*      $OpenBSD: ffs_vfsops.c,v 1.201 2025/09/20 13:53:36 mpi Exp $    */
/*      $NetBSD: ffs_vfsops.c,v 1.19 1996/02/09 22:22:26 christos Exp $ */

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

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/proc.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/socket.h>
#include <sys/mount.h>
#include <sys/buf.h>
#include <sys/mbuf.h>
#include <sys/fcntl.h>
#include <sys/ioctl.h>
#include <sys/errno.h>
#include <sys/malloc.h>
#include <sys/sysctl.h>
#include <sys/pool.h>
#include <sys/dkio.h>
#include <sys/disk.h>
#include <sys/specdev.h>

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

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

#include <uvm/uvm_extern.h>

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

void ffs1_compat_read(struct fs *, struct ufsmount *, daddr_t);
void ffs1_compat_write(struct fs *, struct ufsmount *);

const struct vfsops ffs_vfsops = {
        .vfs_mount      = ffs_mount,
        .vfs_start      = ufs_start,
        .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_vptofh     = ffs_vptofh,
        .vfs_init       = ffs_init,
#ifndef SMALL_KERNEL
        .vfs_sysctl     = ffs_sysctl,
#endif /* SMALL_KERNEL */
        .vfs_checkexp   = ufs_check_export,
};

struct inode_vtbl ffs_vtbl = {
        .iv_truncate    = ffs_truncate,
        .iv_update      = ffs_update,
        .iv_inode_alloc = ffs_inode_alloc,
        .iv_inode_free  = ffs_inode_free,
        .iv_buf_alloc   = ffs_balloc,
        .iv_bufatoff    = ffs_bufatoff
};

int
ffs_checkrange(struct mount *mp, uint32_t ino)
{
        struct buf *bp;
        struct cg *cgp;
        struct fs *fs;
        struct ufsmount *ump;
        int cg, error;

        fs = VFSTOUFS(mp)->um_fs;
        if (ino < ROOTINO || ino >= fs->fs_ncg * fs->fs_ipg)
                return ESTALE;

        /*
         * Need to check if inode is initialized because ffsv2 does
         * lazy initialization and we can get here from nfs_fhtovp
         */
        if (fs->fs_magic != FS_UFS2_MAGIC)
                return 0;

        cg = ino_to_cg(fs, ino);
        ump = VFSTOUFS(mp);

        error = bread(ump->um_devvp, fsbtodb(fs, cgtod(fs, cg)),
            (int)fs->fs_cgsize, &bp);
        if (error)
                return error;

        cgp = (struct cg *)bp->b_data;
        if (!cg_chkmagic(cgp)) {
                brelse(bp);
                return ESTALE;
        }

        brelse(bp);

        if (cg * fs->fs_ipg + cgp->cg_initediblk < ino)
                return ESTALE;

        return 0;
}

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

struct pool ffs_ino_pool;
struct pool ffs_dinode1_pool;
#ifdef FFS2
struct pool ffs_dinode2_pool;
#endif

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

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

        if ((error = vfs_rootmountalloc("ffs", "root_device", &mp)) != 0) {
                vrele(swapdev_vp);
                vrele(rootvp);
                return (error);
        }

        if ((error = ffs_mountfs(rootvp, mp, p)) != 0) {
                vfs_unbusy(mp);
                vfs_mount_free(mp);
                vrele(swapdev_vp);
                vrele(rootvp);
                return (error);
        }

        TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        strlcpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, sizeof(fs->fs_fsmnt));
        (void)ffs_statfs(mp, &mp->mnt_stat, p);
        vfs_unbusy(mp);
        inittodr(fs->fs_time);

        return (0);
}

/*
 * VFS Operations.
 *
 * mount system call
 */
int
ffs_mount(struct mount *mp, const char *path, void *data,
    struct nameidata *ndp, struct proc *p)
{
        struct vnode *devvp;
        struct ufs_args *args = data;
        struct ufsmount *ump = NULL;
        struct fs *fs;
        char fname[MNAMELEN];
        char fspec[MNAMELEN];
        int error = 0, flags;
        int ronly;

        /*
         * If updating, check whether changing from read-only to
         * read/write; if there is no device name, that's all we do.
         */
        if (mp->mnt_flag & MNT_UPDATE) {
                ump = VFSTOUFS(mp);
                fs = ump->um_fs;
                devvp = ump->um_devvp;
                error = 0;
                ronly = fs->fs_ronly;

                if (ronly == 0 && (mp->mnt_flag & MNT_RDONLY)) {
                        /* Flush any dirty data */
                        VFS_SYNC(mp, MNT_WAIT, 0, p->p_ucred, p);

                        /*
                         * Get rid of files open for writing.
                         */
                        flags = WRITECLOSE;
                        if (args == NULL)
                                flags |= IGNORECLEAN;
                        if (mp->mnt_flag & MNT_FORCE)
                                flags |= FORCECLOSE;
                        error = ffs_flushfiles(mp, flags, p);
                        mp->mnt_flag |= MNT_RDONLY;
                        ronly = 1;
                }

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

                if (ronly && (mp->mnt_flag & MNT_WANTRDWR)) {
                        if (fs->fs_clean == 0) {
                                if (mp->mnt_flag & MNT_FORCE) {
                                        printf(
"WARNING: %s was not properly unmounted\n",
                                            fs->fs_fsmnt);
                                } else {
                                        printf(
"WARNING: R/W mount of %s denied.  Filesystem is not clean - run fsck\n",
                                            fs->fs_fsmnt);
                                        error = EROFS;
                                        goto error_1;
                                }
                        }

                        fs->fs_contigdirs = malloc((u_long)fs->fs_ncg,
                             M_UFSMNT, M_WAITOK|M_ZERO);

                        ronly = 0;
                }
                if (args == NULL)
                        goto success;
                if (args->fspec == NULL) {
                        /*
                         * Process export requests.
                         */
                        error = vfs_export(mp, &ump->um_export, 
                            &args->export_info);
                        if (error)
                                goto error_1;
                        else
                                goto success;
                }
        }

        /*
         * Not an update, or updating the name: look up the name
         * and verify that it refers to a sensible block device.
         */
        error = copyinstr(args->fspec, fspec, sizeof(fspec), NULL);
        if (error)
                goto error_1;

        if (disk_map(fspec, fname, MNAMELEN, DM_OPENBLCK) == -1)
                memcpy(fname, fspec, sizeof(fname));

        NDINIT(ndp, LOOKUP, FOLLOW, UIO_SYSSPACE, fname, p);
        if ((error = namei(ndp)) != 0)
                goto error_1;

        devvp = ndp->ni_vp;

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

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

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

                if (devvp != ump->um_devvp) {
                        if (devvp->v_rdev == ump->um_devvp->v_rdev) {
                                vrele(devvp);
                        } else {
                                error = EINVAL; /* needs translation */
                        }
                } else
                        vrele(devvp);
                /*
                 * Update device name only on success
                 */
                if (!error) {
                        /*
                         * Save "mounted from" info for mount point (NULL pad)
                         */
                        memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN);
                        strlcpy(mp->mnt_stat.f_mntfromname, fname, MNAMELEN);
                        memset(mp->mnt_stat.f_mntfromspec, 0, MNAMELEN);
                        strlcpy(mp->mnt_stat.f_mntfromspec, fspec, MNAMELEN);
                }
        } else {
                /*
                 * Since this is a new mount, we want the names for
                 * the device and the mount point copied in.  If an
                 * error occurs,  the mountpoint is discarded by the
                 * upper level code.
                 */
                memset(mp->mnt_stat.f_mntonname, 0, MNAMELEN);
                strlcpy(mp->mnt_stat.f_mntonname, path, MNAMELEN);
                memset(mp->mnt_stat.f_mntfromname, 0, MNAMELEN);
                strlcpy(mp->mnt_stat.f_mntfromname, fname, MNAMELEN);
                memset(mp->mnt_stat.f_mntfromspec, 0, MNAMELEN);
                strlcpy(mp->mnt_stat.f_mntfromspec, fspec, MNAMELEN);

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

        if (error)
                goto error_2;

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

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

                        /*
                         * Updating mount to readonly. Try a cache flush.
                         * Ignore error because the ioctl may not be supported.
                         */
                        VOP_IOCTL(ump->um_devvp, DIOCCACHESYNC, &force,
                            FWRITE, FSCRED, p);
               }
#endif
        }
        return (0);

error_2:        /* error with devvp held */
        vrele (devvp);

error_1:        /* no state to back out */
        return (error);
}

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

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

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

        /*
         * Step 5: invalidate all cached file data.
         */
        if (vget(vp, LK_EXCLUSIVE))
                return (0);

        if (vinvalbuf(vp, 0, fra->cred, fra->p, 0, INFSLP))
                panic("ffs_reload: dirty2");

        /*
         * Step 6: re-read inode data for all active vnodes.
         */
        ip = VTOI(vp);

        error = bread(fra->devvp, 
            fsbtodb(fra->fs, ino_to_fsba(fra->fs, ip->i_number)),
            (int)fra->fs->fs_bsize, &bp);
        if (error) {
                brelse(bp);
                vput(vp);
                return (error);
        }

        if (fra->fs->fs_magic == FS_UFS1_MAGIC)
                *ip->i_din1 = *((struct ufs1_dinode *)bp->b_data +
                    ino_to_fsbo(fra->fs, ip->i_number));
#ifdef FFS2
        else
                *ip->i_din2 = *((struct ufs2_dinode *)bp->b_data +
                    ino_to_fsbo(fra->fs, ip->i_number));
#endif /* FFS2 */
        ip->i_effnlink = DIP(ip, nlink);
        brelse(bp);
        vput(vp);
        return (0);
}

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

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

        /*
         * Step 2: re-read superblock from disk.
         */
        fs = VFSTOUFS(mountp)->um_fs;

        error = bread(devvp, fs->fs_sblockloc / DEV_BSIZE, SBSIZE, &bp);
        if (error) {
                brelse(bp);
                return (error);
        }

        newfs = (struct fs *)bp->b_data;
        if (ffs_validate(newfs) == 0) {
                brelse(bp);
                return (EINVAL);
        }

        /*
         * Copy pointer fields back into superblock before copying in   XXX
         * new superblock. These should really be in the ufsmount.      XXX
         * Note that important parameters (eg fs_ncg) are unchanged.
         */
        newfs->fs_csp = fs->fs_csp;
        newfs->fs_maxcluster = fs->fs_maxcluster;
        newfs->fs_ronly = fs->fs_ronly;
        memcpy(fs, newfs, fs->fs_sbsize);
        if (fs->fs_sbsize < SBSIZE)
                bp->b_flags |= B_INVAL;
        brelse(bp);
        VFSTOUFS(mountp)->um_maxsymlinklen = fs->fs_maxsymlinklen;
        ffs1_compat_read(fs, VFSTOUFS(mountp), fs->fs_sblockloc);
        ffs_oldfscompat(fs);
        (void)ffs_statfs(mountp, &mountp->mnt_stat, p);
        /*
         * Step 3: re-read summary information from disk.
         */
        blks = howmany(fs->fs_cssize, fs->fs_fsize);
        space = (caddr_t)fs->fs_csp;
        for (i = 0; i < blks; i += fs->fs_frag) {
                size = fs->fs_bsize;
                if (i + fs->fs_frag > blks)
                        size = (blks - i) * fs->fs_fsize;
                error = bread(devvp, fsbtodb(fs, fs->fs_csaddr + i), size, &bp);
                if (error) {
                        brelse(bp);
                        return (error);
                }
                memcpy(space, bp->b_data, size);
                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;
        }

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

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

        return (error);
}

/*
 * Checks if a super block is sane enough to be mounted.
 */
int
ffs_validate(struct fs *fsp)
{
#ifdef FFS2
        if (fsp->fs_magic != FS_UFS2_MAGIC && fsp->fs_magic != FS_UFS1_MAGIC)
                return (0); /* Invalid magic */
#else
        if (fsp->fs_magic != FS_UFS1_MAGIC)
                return (0); /* Invalid magic */
#endif /* FFS2 */

        if ((u_int)fsp->fs_bsize > MAXBSIZE)
                return (0); /* Invalid block size */

        if ((u_int)fsp->fs_bsize < sizeof(struct fs))
                return (0); /* Invalid block size */

        if ((u_int)fsp->fs_sbsize > SBSIZE)
                return (0); /* Invalid super block size */

        if ((u_int)fsp->fs_frag > MAXFRAG || fragtbl[fsp->fs_frag] == NULL)
                return (0); /* Invalid number of fragments */

        if (fsp->fs_inodefmt == FS_42INODEFMT)
                return (0); /* Obsolete format, support broken in 2014 */
        if (fsp->fs_maxsymlinklen <= 0)
                return (0); /* Invalid max size of short symlink */

        return (1); /* Super block is okay */
}

/*
 * Possible locations for the super-block.
 */
const int sbtry[] = SBLOCKSEARCH;

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

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

        ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
        error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p);
        if (error)
                return (error);

        bp = NULL;
        ump = NULL;

        /*
         * Try reading the super-block in each of its possible locations.
         */
        for (i = 0; sbtry[i] != -1; i++) {
                if (bp != NULL) {
                        bp->b_flags |= B_NOCACHE;
                        brelse(bp);
                        bp = NULL;
                }

                error = bread(devvp, sbtry[i] / DEV_BSIZE, SBSIZE, &bp);
                if (error)
                        goto out;

                fs = (struct fs *) bp->b_data;
                sbloc = sbtry[i];

                /*
                 * Do not look for an FFS1 file system at SBLOCK_UFS2. Doing so
                 * will find the wrong super-block for file systems with 64k
                 * block size.
                 */
                if (fs->fs_magic == FS_UFS1_MAGIC && sbloc == SBLOCK_UFS2)
                        continue;

                if (ffs_validate(fs))
                        break; /* Super block validated */
        }

        if (sbtry[i] == -1) {
                error = EINVAL;
                goto out;
        }

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

        if (fs->fs_postblformat == FS_42POSTBLFMT && !ronly) {
#ifndef SMALL_KERNEL
                printf("ffs_mountfs(): obsolete rotational table format, "
                    "please use fsck_ffs(8) -c 1\n");
#endif
                error = EROFS;
                goto out;
        }

        ump = malloc(sizeof *ump, M_UFSMNT, M_WAITOK|M_ZERO);
        ump->um_fs = malloc((u_long)fs->fs_sbsize, M_UFSMNT,
            M_WAITOK);

        if (fs->fs_magic == FS_UFS1_MAGIC)
                ump->um_fstype = UM_UFS1;
#ifdef FFS2
        else
                ump->um_fstype = UM_UFS2;
#endif

        memcpy(ump->um_fs, bp->b_data, fs->fs_sbsize);
        if (fs->fs_sbsize < SBSIZE)
                bp->b_flags |= B_INVAL;
        brelse(bp);
        bp = NULL;
        fs = ump->um_fs;

        ffs1_compat_read(fs, ump, sbloc);

        if (fs->fs_clean == 0)
                fs->fs_flags |= FS_UNCLEAN;
        fs->fs_ronly = ronly;
        size = fs->fs_cssize;
        blks = howmany(size, fs->fs_fsize);
        if (fs->fs_contigsumsize > 0)
                size += fs->fs_ncg * sizeof(int32_t);
        space = malloc((u_long)size, M_UFSMNT, M_WAITOK);
        fs->fs_csp = (struct csum *)space;
        for (i = 0; i < blks; i += fs->fs_frag) {
                size = fs->fs_bsize;
                if (i + fs->fs_frag > blks)
                        size = (blks - i) * fs->fs_fsize;
                error = bread(devvp, fsbtodb(fs, fs->fs_csaddr + i), size, &bp);
                if (error) {
                        free(fs->fs_csp, M_UFSMNT, 0);
                        goto out;
                }
                memcpy(space, bp->b_data, size);
                space += size;
                brelse(bp);
                bp = NULL;
        }
        if (fs->fs_contigsumsize > 0) {
                fs->fs_maxcluster = lp = (int32_t *)space;
                for (i = 0; i < fs->fs_ncg; i++)
                        *lp++ = fs->fs_contigsumsize;
        }
        mp->mnt_data = ump;
        mp->mnt_stat.f_fsid.val[0] = (long)dev;
        /* Use on-disk fsid if it exists, else fake it */
        if (fs->fs_id[0] != 0 && fs->fs_id[1] != 0)
                mp->mnt_stat.f_fsid.val[1] = fs->fs_id[1];
        else
                mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
        mp->mnt_stat.f_namemax = MAXNAMLEN;
        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;
        ump->um_maxsymlinklen = fs->fs_maxsymlinklen;
        for (i = 0; i < MAXQUOTAS; i++)
                ump->um_quotas[i] = NULL;

        devvp->v_specmountpoint = mp;
        ffs_oldfscompat(fs);

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

        /*
         * Set FS local "last mounted on" information (NULL pad)
         */
        memset(fs->fs_fsmnt, 0, sizeof(fs->fs_fsmnt));
        strlcpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, sizeof(fs->fs_fsmnt));

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

        /*
         * XXX
         * Limit max file size.  Even though ffs can handle files up to 16TB,
         * we do limit the max file to 2^31 pages to prevent overflow of
         * a 32-bit unsigned int.  The buffer cache has its own checks but
         * a little added paranoia never hurts.
         */
        ump->um_savedmaxfilesize = fs->fs_maxfilesize;          /* XXX */
        maxfilesize = FS_KERNMAXFILESIZE(PAGE_SIZE, fs);
        if (fs->fs_maxfilesize > maxfilesize)                   /* XXX */
                fs->fs_maxfilesize = maxfilesize;               /* XXX */
        if (ronly == 0) {
                fs->fs_fmod = 1;
                fs->fs_clean = 0;
                error = ffs_sbupdate(ump, MNT_WAIT);
                if (error == EROFS)
                        goto out;
        }
        return (0);
out:
        if (devvp->v_specinfo)
                devvp->v_specmountpoint = NULL;
        if (bp)
                brelse(bp);

        vn_lock(devvp, LK_EXCLUSIVE|LK_RETRY);
        (void)VOP_CLOSE(devvp, ronly ? FREAD : FREAD|FWRITE, cred, p);
        VOP_UNLOCK(devvp);

        if (ump) {
                free(ump->um_fs, M_UFSMNT, ump->um_fs->fs_sbsize);
                free(ump, M_UFSMNT, sizeof(*ump));
                mp->mnt_data = NULL;
        }
        return (error);
}

/*
 * Sanity checks for old file systems.
 */
int
ffs_oldfscompat(struct fs *fs)
{
        int i;

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

/*
 * Auxiliary function for reading FFS1 super blocks.
 */
void
ffs1_compat_read(struct fs *fs, struct ufsmount *ump, daddr_t sbloc)
{
        if (fs->fs_magic == FS_UFS2_MAGIC)
                return; /* UFS2 */
#if 0
        if (fs->fs_ffs1_flags & FS_FLAGS_UPDATED)
                return; /* Already updated */
#endif
        fs->fs_flags = fs->fs_ffs1_flags;
        fs->fs_sblockloc = sbloc;
        fs->fs_maxbsize = fs->fs_bsize;
        fs->fs_time = fs->fs_ffs1_time;
        fs->fs_size = fs->fs_ffs1_size;
        fs->fs_dsize = fs->fs_ffs1_dsize;
        fs->fs_csaddr = fs->fs_ffs1_csaddr;
        fs->fs_cstotal.cs_ndir = fs->fs_ffs1_cstotal.cs_ndir;
        fs->fs_cstotal.cs_nbfree = fs->fs_ffs1_cstotal.cs_nbfree;
        fs->fs_cstotal.cs_nifree = fs->fs_ffs1_cstotal.cs_nifree;
        fs->fs_cstotal.cs_nffree = fs->fs_ffs1_cstotal.cs_nffree;
        fs->fs_ffs1_flags |= FS_FLAGS_UPDATED;
}

/*
 * Auxiliary function for writing FFS1 super blocks.
 */
void
ffs1_compat_write(struct fs *fs, struct ufsmount *ump)
{
        if (fs->fs_magic != FS_UFS1_MAGIC)
                return; /* UFS2 */

        fs->fs_ffs1_time = fs->fs_time;
        fs->fs_ffs1_cstotal.cs_ndir = fs->fs_cstotal.cs_ndir;
        fs->fs_ffs1_cstotal.cs_nbfree = fs->fs_cstotal.cs_nbfree;
        fs->fs_ffs1_cstotal.cs_nifree = fs->fs_cstotal.cs_nifree;
        fs->fs_ffs1_cstotal.cs_nffree = fs->fs_cstotal.cs_nffree;
}

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

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

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

        if (fs->fs_ronly == 0) {
                fs->fs_clean = (fs->fs_flags & FS_UNCLEAN) ? 0 : 1;
                error = ffs_sbupdate(ump, MNT_WAIT);
                /* ignore write errors if mounted RW on read-only device */
                if (error && error != EROFS) {
                        fs->fs_clean = 0;
                        return (error);
                }
                free(fs->fs_contigdirs, M_UFSMNT, fs->fs_ncg);
        }
        ump->um_devvp->v_specmountpoint = NULL;

        vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
        vinvalbuf(ump->um_devvp, V_SAVE, NOCRED, p, 0, INFSLP);
        (void)VOP_CLOSE(ump->um_devvp, fs->fs_ronly ? FREAD : FREAD|FWRITE,
            NOCRED, p);
        vput(ump->um_devvp);
        free(fs->fs_csp, M_UFSMNT, 0);
        free(fs, M_UFSMNT, fs->fs_sbsize);
        free(ump, M_UFSMNT, sizeof(*ump));
        mp->mnt_data = NULL;
        mp->mnt_flag &= ~MNT_LOCAL;
        return (0);
}

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

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

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

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

        ump = VFSTOUFS(mp);
        fs = ump->um_fs;

#ifdef FFS2
        if (fs->fs_magic != FS_MAGIC && fs->fs_magic != FS_UFS2_MAGIC)
                panic("ffs_statfs");
#else
        if (fs->fs_magic != FS_MAGIC)
                panic("ffs_statfs");
#endif /* FFS2 */

        sbp->f_bsize = fs->fs_fsize;
        sbp->f_iosize = fs->fs_bsize;
        sbp->f_blocks = fs->fs_dsize;
        sbp->f_bfree = fs->fs_cstotal.cs_nbfree * fs->fs_frag +
            fs->fs_cstotal.cs_nffree;
        sbp->f_bavail = sbp->f_bfree -
            ((int64_t)fs->fs_dsize * fs->fs_minfree / 100);
        sbp->f_files = fs->fs_ncg * fs->fs_ipg - ROOTINO;
        sbp->f_ffree = fs->fs_cstotal.cs_nifree;
        sbp->f_favail = sbp->f_ffree;
        copy_statfs_info(sbp, mp);

        return (0);
}

struct ffs_sync_args {
        int allerror;
        struct proc *p;
        int waitfor;
        int nlink0;
        int inflight;
        struct ucred *cred;
};

int
ffs_sync_vnode(struct vnode *vp, void *arg)
{
        struct ffs_sync_args *fsa = arg;
        struct inode *ip;
        int error, nlink0 = 0;
        int s, skip = 0;

        if (vp->v_type == VNON)
                return (0);

        ip = VTOI(vp);

        /*
         * If unmounting or converting rw to ro, then stop deferring
         * timestamp writes.
         */
        if (fsa->waitfor == MNT_WAIT && (ip->i_flag & IN_LAZYMOD)) {
                ip->i_flag |= IN_MODIFIED;
                UFS_UPDATE(ip, 1);
        }

        if (ip->i_effnlink == 0)
                nlink0 = 1;

        s = splbio();
        if ((ip->i_flag &
            (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
            LIST_EMPTY(&vp->v_dirtyblkhd)) {
                skip = 1;
        }
        splx(s);

        if (skip)
                goto end;

        if (vget(vp, LK_EXCLUSIVE | LK_NOWAIT)) {
                fsa->inflight = MIN(fsa->inflight+1, 65536);
                goto end;
        }

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

end:
        fsa->nlink0 = MIN(fsa->nlink0 + nlink0, 65536);
        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.
 *
 * Should always be called with the mount point locked.
 */
int
ffs_sync(struct mount *mp, int waitfor, int stall, struct ucred *cred, struct proc *p)
{
        struct ufsmount *ump = VFSTOUFS(mp);
        struct fs *fs;
        int error, allerror = 0, clean, fmod;
        struct ffs_sync_args fsa;

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

        /*
         * Write back each (modified) inode.
         */
        fsa.allerror = 0;
        fsa.p = p;
        fsa.cred = cred;
        fsa.waitfor = waitfor;
        fsa.nlink0 = 0;
        fsa.inflight = 0;

        /*
         * Don't traverse the vnode list if we want to skip all of them.
         */
        if (waitfor != MNT_LAZY) {
                vfs_mount_foreach_vnode(mp, ffs_sync_vnode, &fsa);
                allerror = fsa.allerror;
        }

        /*
         * Force stale file system control information to be flushed.
         */
        if (waitfor != MNT_LAZY) {
                vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
                if ((error = VOP_FSYNC(ump->um_devvp, cred, waitfor, p)) != 0)
                        allerror = error;
                VOP_UNLOCK(ump->um_devvp);
        }
        qsync(mp);
        /*
         * Write back modified superblock.
         */
        clean = fs->fs_clean;
        fmod = fs->fs_fmod;
        if (stall && fs->fs_ronly == 0) {
                fs->fs_fmod = 1;
                if (allerror == 0 && fsa.nlink0 == 0 && fsa.inflight == 0) {
                        fs->fs_clean = (fs->fs_flags & FS_UNCLEAN) ? 0 : 1;
#if 0
                        printf("%s force clean (dangling %d inflight %d)\n",
                            mp->mnt_stat.f_mntonname, fsa.nlink0, fsa.inflight);
#endif
                } else {
                        fs->fs_clean = 0;
#if 0
                        printf("%s force dirty (dangling %d inflight %d)\n",
                            mp->mnt_stat.f_mntonname, fsa.nlink0, fsa.inflight);
#endif
                }
        }
        if (fs->fs_fmod != 0 && (error = ffs_sbupdate(ump, waitfor)) != 0)
                allerror = error;
        fs->fs_clean = clean;
        fs->fs_fmod = fmod;

        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(struct mount *mp, ino_t ino, struct vnode **vpp)
{
        struct fs *fs;
        struct inode *ip;
        struct ufs1_dinode *dp1;
#ifdef FFS2
        struct ufs2_dinode *dp2;
#endif
        struct ufsmount *ump;
        struct buf *bp;
        struct vnode *vp;
        dev_t dev;
        int error;

        if (ino > (ufsino_t)-1)
                panic("ffs_vget: alien ino_t %llu", (unsigned long long)ino);

        ump = VFSTOUFS(mp);
        dev = ump->um_dev;
retry:
        if ((*vpp = ufs_ihashget(dev, ino)) != NULL)
                return (0);

        /* Allocate a new vnode/inode. */
        if ((error = getnewvnode(VT_UFS, mp, &ffs_vops, &vp)) != 0) {
                *vpp = NULL;
                return (error);
        }

#ifdef VFSLCKDEBUG
        vp->v_flag |= VLOCKSWORK;
#endif
        ip = pool_get(&ffs_ino_pool, PR_WAITOK|PR_ZERO);
        rrw_init_flags(&ip->i_lock, "inode", RWL_DUPOK | RWL_IS_VNODE);
        ip->i_ump = ump;
        vref(ip->i_devvp);
        vp->v_data = ip;
        ip->i_vnode = vp;
        ip->i_fs = fs = ump->um_fs;
        ip->i_dev = dev;
        ip->i_number = ino;
        ip->i_vtbl = &ffs_vtbl;

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

                if (error == EEXIST)
                        goto retry;

                return (error);
        }


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

#ifdef FFS2
        if (ip->i_ump->um_fstype == UM_UFS2) {
                ip->i_din2 = pool_get(&ffs_dinode2_pool, PR_WAITOK);
                dp2 = (struct ufs2_dinode *) bp->b_data + ino_to_fsbo(fs, ino);
                *ip->i_din2 = *dp2;
        } else
#endif
        {
                ip->i_din1 = pool_get(&ffs_dinode1_pool, PR_WAITOK);
                dp1 = (struct ufs1_dinode *) bp->b_data + ino_to_fsbo(fs, ino);
                *ip->i_din1 = *dp1;
        }

        brelse(bp);

        ip->i_effnlink = DIP(ip, nlink);

        /*
         * Initialize the vnode from the inode, check for aliases.
         * Note that the underlying vnode may have changed.
         */
        if ((error = ffs_vinit(mp, &vp)) != 0) {
                vput(vp);
                *vpp = NULL;
                return (error);
        }

        /*
         * Set up a generation number for this inode if it does not
         * already have one. This should only happen on old filesystems.
         */
        if (DIP(ip, gen) == 0) {
                while (DIP(ip, gen) == 0)
                        DIP_ASSIGN(ip, gen, arc4random());
                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_magic == FS_UFS1_MAGIC && fs->fs_inodefmt < FS_44INODEFMT) {
                ip->i_ffs1_uid = ip->i_din1->di_ouid;
                ip->i_ffs1_gid = ip->i_din1->di_ogid;
        }

        *vpp = vp;

        return (0);
}

/*
 * File handle to vnode
 *
 * Have to be really careful about stale file handles.
 */
int
ffs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp)
{
        struct ufid *ufhp;
        int error;

        ufhp = (struct ufid *)fhp;
        if (ufhp->ufid_len != sizeof(*ufhp))
                return EINVAL;

        if ((error = ffs_checkrange(mp, ufhp->ufid_ino)) != 0)
                return error;

        return (ufs_fhtovp(mp, ufhp, vpp));
}

/*
 * Vnode pointer to File handle
 */
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 = DIP(ip, gen);

        return (0);
}

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

        /*
         * First write back the summary information.
         */
        blks = howmany(fs->fs_cssize, fs->fs_fsize);
        space = (caddr_t)fs->fs_csp;
        for (i = 0; i < blks; i += fs->fs_frag) {
                size = fs->fs_bsize;
                if (i + fs->fs_frag > blks)
                        size = (blks - i) * fs->fs_fsize;
                bp = getblk(mp->um_devvp, fsbtodb(fs, fs->fs_csaddr + i),
                    size, 0, INFSLP);
                memcpy(bp->b_data, space, size);
                space += size;
                if (waitfor != MNT_WAIT)
                        bawrite(bp);
                else if ((error = bwrite(bp)))
                        allerror = error;
        }

        /*
         * Now write back the superblock itself. If any errors occurred
         * up to this point, then fail so that the superblock avoids
         * being written out as clean.
         */
        if (allerror) {
                return (allerror);
        }

        bp = getblk(mp->um_devvp,
            fs->fs_sblockloc >> (fs->fs_fshift - fs->fs_fsbtodb),
            (int)fs->fs_sbsize, 0, INFSLP);
        fs->fs_fmod = 0;
#ifndef BOOT_KERNEL
        fs->fs_time = gettime();
#endif
        memcpy(bp->b_data, fs, fs->fs_sbsize);
        /* Restore compatibility to old file systems.              XXX */
        dfs = (struct fs *)bp->b_data;                          /* XXX */
        if (fs->fs_postblformat == FS_42POSTBLFMT)              /* XXX */
                dfs->fs_nrpos = -1;                             /* XXX */
        if (fs->fs_inodefmt < FS_44INODEFMT) {                  /* XXX */
                int32_t *lp, tmp;                               /* XXX */
                                                                /* XXX */
                lp = (int32_t *)&dfs->fs_qbmask;                /* XXX */
                tmp = lp[4];                                    /* XXX */
                for (i = 4; i > 0; i--)                         /* XXX */
                        lp[i] = lp[i-1];                        /* XXX */
                lp[0] = tmp;                                    /* XXX */
        }                                                       /* XXX */
        dfs->fs_maxfilesize = mp->um_savedmaxfilesize;          /* XXX */

        ffs1_compat_write(dfs, mp);

        if (waitfor != MNT_WAIT)
                bawrite(bp);
        else if ((error = bwrite(bp)))
                allerror = error;

        return (allerror);
}

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

        if (done)
                return (0);

        done = 1;

        pool_init(&ffs_ino_pool, sizeof(struct inode), 0, IPL_NONE,
            PR_WAITOK, "ffsino", NULL);
        pool_init(&ffs_dinode1_pool, sizeof(struct ufs1_dinode), 0, IPL_NONE,
            PR_WAITOK, "dino1pl", NULL);
#ifdef FFS2
        pool_init(&ffs_dinode2_pool, sizeof(struct ufs2_dinode), 0, IPL_NONE,
            PR_WAITOK, "dino2pl", NULL);
#endif

        return (ufs_init(vfsp));
}

#ifndef SMALL_KERNEL
const struct sysctl_bounded_args ffs_vars[] = {
#ifdef UFS_DIRHASH
        { FFS_DIRHASH_DIRSIZE, &ufs_mindirhashsize, 0, INT_MAX },
        { FFS_DIRHASH_MAXMEM, &ufs_dirhashmaxmem, 0, INT_MAX },
        { FFS_DIRHASH_MEM, &ufs_dirhashmem, SYSCTL_INT_READONLY },
#endif
};

/*
 * fast filesystem related variables.
 */
int
ffs_sysctl(int *name, u_int namelen, void *oldp, size_t *oldlenp, void *newp,
    size_t newlen, struct proc *p)
{
        return sysctl_bounded_arr(ffs_vars, nitems(ffs_vars), name,
            namelen, oldp, oldlenp, newp, newlen);
}
#endif /* SMALL_KERNEL */