root/sys/ufs/ffs/ffs_vfsops.c
/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * 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.
 */

#include <sys/cdefs.h>
#include "opt_quota.h"
#include "opt_ufs.h"
#include "opt_ffs.h"
#include "opt_ddb.h"

#include <sys/param.h>
#include <sys/gsb_crc32.h>
#include <sys/systm.h>
#include <sys/namei.h>
#include <sys/priv.h>
#include <sys/proc.h>
#include <sys/taskqueue.h>
#include <sys/kernel.h>
#include <sys/ktr.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/ioccom.h>
#include <sys/malloc.h>
#include <sys/mutex.h>
#include <sys/rwlock.h>
#include <sys/sysctl.h>
#include <sys/vmmeter.h>

#include <security/mac/mac_framework.h>

#include <ufs/ufs/dir.h>
#include <ufs/ufs/extattr.h>
#include <ufs/ufs/gjournal.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>

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

#include <geom/geom.h>
#include <geom/geom_vfs.h>

#include <ddb/ddb.h>

static uma_zone_t uma_inode, uma_ufs1, uma_ufs2;
VFS_SMR_DECLARE;

static int      ffs_mountfs(struct vnode *, struct mount *, struct thread *);
static void     ffs_ifree(struct ufsmount *ump, struct inode *ip);
static int      ffs_sync_lazy(struct mount *mp);
static int      ffs_use_bread(void *devfd, off_t loc, void **bufp, int size);
static int      ffs_use_bwrite(void *devfd, off_t loc, void *buf, int size);

static vfs_init_t ffs_init;
static vfs_uninit_t ffs_uninit;
static vfs_extattrctl_t ffs_extattrctl;
static vfs_cmount_t ffs_cmount;
static vfs_unmount_t ffs_unmount;
static vfs_mount_t ffs_mount;
static vfs_statfs_t ffs_statfs;
static vfs_fhtovp_t ffs_fhtovp;
static vfs_sync_t ffs_sync;

static struct vfsops ufs_vfsops = {
        .vfs_extattrctl =       ffs_extattrctl,
        .vfs_fhtovp =           ffs_fhtovp,
        .vfs_init =             ffs_init,
        .vfs_mount =            ffs_mount,
        .vfs_cmount =           ffs_cmount,
        .vfs_quotactl =         ufs_quotactl,
        .vfs_root =             vfs_cache_root,
        .vfs_cachedroot =       ufs_root,
        .vfs_statfs =           ffs_statfs,
        .vfs_sync =             ffs_sync,
        .vfs_uninit =           ffs_uninit,
        .vfs_unmount =          ffs_unmount,
        .vfs_vget =             ffs_vget,
        .vfs_susp_clean =       process_deferred_inactive,
};

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

static b_strategy_t ffs_geom_strategy;
static b_write_t ffs_bufwrite;

static struct buf_ops ffs_ops = {
        .bop_name =     "FFS",
        .bop_write =    ffs_bufwrite,
        .bop_strategy = ffs_geom_strategy,
        .bop_sync =     bufsync,
#ifdef NO_FFS_SNAPSHOT
        .bop_bdflush =  bufbdflush,
#else
        .bop_bdflush =  ffs_bdflush,
#endif
};

/*
 * Note that userquota and groupquota options are not currently used
 * by UFS/FFS code and generally mount(8) does not pass those options
 * from userland, but they can be passed by loader(8) via
 * vfs.root.mountfrom.options.
 */
static const char *ffs_opts[] = { "acls", "async", "noatime", "noclusterr",
    "noclusterw", "noexec", "export", "force", "from", "groupquota",
    "multilabel", "nfsv4acls", "snapshot", "nosuid", "suiddir",
    "nosymfollow", "sync", "union", "userquota", "untrusted", NULL };

static int ffs_enxio_enable = 1;
SYSCTL_DECL(_vfs_ffs);
SYSCTL_INT(_vfs_ffs, OID_AUTO, enxio_enable, CTLFLAG_RWTUN,
    &ffs_enxio_enable, 0,
    "enable mapping of other disk I/O errors to ENXIO");

/*
 * Return buffer with the contents of block "offset" from the beginning of
 * directory "ip".  If "res" is non-zero, fill it in with a pointer to the
 * remaining space in the directory.
 */
static int
ffs_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp)
{
        struct inode *ip;
        struct fs *fs;
        struct buf *bp;
        ufs_lbn_t lbn;
        int bsize, error;

        ip = VTOI(vp);
        fs = ITOFS(ip);
        lbn = lblkno(fs, offset);
        bsize = blksize(fs, ip, lbn);

        *bpp = NULL;
        error = bread(vp, lbn, bsize, NOCRED, &bp);
        if (error) {
                return (error);
        }
        if (res)
                *res = (char *)bp->b_data + blkoff(fs, offset);
        *bpp = bp;
        return (0);
}

/*
 * Load up the contents of an inode and copy the appropriate pieces
 * to the incore copy.
 */
static int
ffs_load_inode(struct buf *bp, struct inode *ip, struct fs *fs, ino_t ino)
{
        struct ufs1_dinode *dip1;
        struct ufs2_dinode *dip2;
        time_t now;
        int error;

        now = time_second > fs->fs_time ? time_second : fs->fs_time;
        if (I_IS_UFS1(ip)) {
                dip1 = ip->i_din1;
                *dip1 =
                    *((struct ufs1_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
                ip->i_mode = dip1->di_mode;
                ip->i_nlink = dip1->di_nlink;
                ip->i_effnlink = dip1->di_nlink;
                ip->i_size = dip1->di_size;
                ip->i_flags = dip1->di_flags;
                ip->i_gen = dip1->di_gen;
                ip->i_uid = dip1->di_uid;
                ip->i_gid = dip1->di_gid;
                if (ffs_oldfscompat_inode_read(fs, ip->i_dp, now) &&
                    fs->fs_ronly == 0)
                        UFS_INODE_SET_FLAG(ip, IN_MODIFIED);
                return (0);
        }
        dip2 = ((struct ufs2_dinode *)bp->b_data + ino_to_fsbo(fs, ino));
        if ((error = ffs_verify_dinode_ckhash(fs, dip2)) != 0 &&
            !ffs_fsfail_cleanup(ITOUMP(ip), error)) {
                printf("%s: inode %jd: check-hash failed\n", fs->fs_fsmnt,
                    (intmax_t)ino);
                return (error);
        }
        *ip->i_din2 = *dip2;
        dip2 = ip->i_din2;
        ip->i_mode = dip2->di_mode;
        ip->i_nlink = dip2->di_nlink;
        ip->i_effnlink = dip2->di_nlink;
        ip->i_size = dip2->di_size;
        ip->i_flags = dip2->di_flags;
        ip->i_gen = dip2->di_gen;
        ip->i_uid = dip2->di_uid;
        ip->i_gid = dip2->di_gid;
        if (ffs_oldfscompat_inode_read(fs, ip->i_dp, now) && fs->fs_ronly == 0)
                UFS_INODE_SET_FLAG(ip, IN_MODIFIED);
        return (0);
}

/*
 * Verify that a filesystem block number is a valid data block.
 * This routine is only called on untrusted filesystems.
 */
static int
ffs_check_blkno(struct mount *mp, ino_t inum, ufs2_daddr_t daddr, int blksize)
{
        struct fs *fs;
        struct ufsmount *ump;
        ufs2_daddr_t end_daddr;
        int cg, havemtx;

        KASSERT((mp->mnt_flag & MNT_UNTRUSTED) != 0,
            ("ffs_check_blkno called on a trusted file system"));
        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        cg = dtog(fs, daddr);
        end_daddr = daddr + numfrags(fs, blksize);
        /*
         * Verify that the block number is a valid data block. Also check
         * that it does not point to an inode block or a superblock. Accept
         * blocks that are unalloacted (0) or part of snapshot metadata
         * (BLK_NOCOPY or BLK_SNAP).
         *
         * Thus, the block must be in a valid range for the filesystem and
         * either in the space before a backup superblock (except the first
         * cylinder group where that space is used by the bootstrap code) or
         * after the inode blocks and before the end of the cylinder group.
         */
        if ((uint64_t)daddr <= BLK_SNAP ||
            ((uint64_t)end_daddr <= fs->fs_size &&
            ((cg > 0 && end_daddr <= cgsblock(fs, cg)) ||
            (daddr >= cgdmin(fs, cg) &&
            end_daddr <= cgbase(fs, cg) + fs->fs_fpg))))
                return (0);
        if ((havemtx = mtx_owned(UFS_MTX(ump))) == 0)
                UFS_LOCK(ump);
        if (ppsratecheck(&ump->um_last_integritymsg,
            &ump->um_secs_integritymsg, 1)) {
                UFS_UNLOCK(ump);
                uprintf("\n%s: inode %jd, out-of-range indirect block "
                    "number %jd\n", mp->mnt_stat.f_mntonname, inum, daddr);
                if (havemtx)
                        UFS_LOCK(ump);
        } else if (!havemtx)
                UFS_UNLOCK(ump);
        return (EINTEGRITY);
}

/*
 * On first ENXIO error, initiate an asynchronous forcible unmount.
 * Used to unmount filesystems whose underlying media has gone away.
 *
 * Return true if a cleanup is in progress.
 */
int
ffs_fsfail_cleanup(struct ufsmount *ump, int error)
{
        int retval;

        UFS_LOCK(ump);
        retval = ffs_fsfail_cleanup_locked(ump, error);
        UFS_UNLOCK(ump);
        return (retval);
}

int
ffs_fsfail_cleanup_locked(struct ufsmount *ump, int error)
{
        mtx_assert(UFS_MTX(ump), MA_OWNED);
        if (error == ENXIO && (ump->um_flags & UM_FSFAIL_CLEANUP) == 0) {
                ump->um_flags |= UM_FSFAIL_CLEANUP;
                if (ump->um_mountp == rootvnode->v_mount)
                        panic("UFS: root fs would be forcibly unmounted");

                /*
                 * Queue an async forced unmount.
                 */
                vfs_ref(ump->um_mountp);
                dounmount(ump->um_mountp,
                    MNT_FORCE | MNT_RECURSE | MNT_DEFERRED, curthread);
                printf("UFS: forcibly unmounting %s from %s\n",
                    ump->um_mountp->mnt_stat.f_mntfromname,
                    ump->um_mountp->mnt_stat.f_mntonname);
        }
        return ((ump->um_flags & UM_FSFAIL_CLEANUP) != 0);
}

/*
 * Wrapper used during ENXIO cleanup to allocate empty buffers when
 * the kernel is unable to read the real one. They are needed so that
 * the soft updates code can use them to unwind its dependencies.
 */
int
ffs_breadz(struct ufsmount *ump, struct vnode *vp, daddr_t lblkno,
    daddr_t dblkno, int size, daddr_t *rablkno, int *rabsize, int cnt,
    struct ucred *cred, int flags, void (*ckhashfunc)(struct buf *),
    struct buf **bpp)
{
        int error;

        flags |= GB_CVTENXIO;
        error = breadn_flags(vp, lblkno, dblkno, size, rablkno, rabsize, cnt,
            cred, flags, ckhashfunc, bpp);
        if (error != 0 && ffs_fsfail_cleanup(ump, error)) {
                error = getblkx(vp, lblkno, dblkno, size, 0, 0, flags, bpp);
                KASSERT(error == 0, ("getblkx failed"));
                vfs_bio_bzero_buf(*bpp, 0, size);
        }
        return (error);
}

static int
ffs_mount(struct mount *mp)
{
        struct vnode *devvp, *odevvp;
        struct thread *td;
        struct ufsmount *ump = NULL;
        struct fs *fs;
        int error, flags;
        int error1 __diagused;
        uint64_t mntorflags, saved_mnt_flag;
        accmode_t accmode;
        struct nameidata ndp;
        char *fspec;
        bool mounted_softdep;

        td = curthread;
        if (vfs_filteropt(mp->mnt_optnew, ffs_opts))
                return (EINVAL);
        if (uma_inode == NULL) {
                uma_inode = uma_zcreate("FFS inode",
                    sizeof(struct inode), NULL, NULL, NULL, NULL,
                    UMA_ALIGN_PTR, 0);
                uma_ufs1 = uma_zcreate("FFS1 dinode",
                    sizeof(struct ufs1_dinode), NULL, NULL, NULL, NULL,
                    UMA_ALIGN_PTR, 0);
                uma_ufs2 = uma_zcreate("FFS2 dinode",
                    sizeof(struct ufs2_dinode), NULL, NULL, NULL, NULL,
                    UMA_ALIGN_PTR, 0);
                VFS_SMR_ZONE_SET(uma_inode);
        }

        vfs_deleteopt(mp->mnt_optnew, "groupquota");
        vfs_deleteopt(mp->mnt_optnew, "userquota");

        fspec = vfs_getopts(mp->mnt_optnew, "from", &error);
        if (error)
                return (error);

        mntorflags = 0;
        if (vfs_getopt(mp->mnt_optnew, "untrusted", NULL, NULL) == 0)
                mntorflags |= MNT_UNTRUSTED;

        if (vfs_getopt(mp->mnt_optnew, "acls", NULL, NULL) == 0)
                mntorflags |= MNT_ACLS;

        if (vfs_getopt(mp->mnt_optnew, "snapshot", NULL, NULL) == 0) {
                mntorflags |= MNT_SNAPSHOT;
                /*
                 * Once we have set the MNT_SNAPSHOT flag, do not
                 * persist "snapshot" in the options list.
                 */
                vfs_deleteopt(mp->mnt_optnew, "snapshot");
                vfs_deleteopt(mp->mnt_opt, "snapshot");
        }

        if (vfs_getopt(mp->mnt_optnew, "nfsv4acls", NULL, NULL) == 0) {
                if (mntorflags & MNT_ACLS) {
                        vfs_mount_error(mp,
                            "\"acls\" and \"nfsv4acls\" options "
                            "are mutually exclusive");
                        return (EINVAL);
                }
                mntorflags |= MNT_NFS4ACLS;
        }

        MNT_ILOCK(mp);
        mp->mnt_kern_flag &= ~MNTK_FPLOOKUP;
        mp->mnt_flag |= mntorflags;
        MNT_IUNLOCK(mp);

        /*
         * If this is a snapshot request, take the snapshot.
         */
        if (mp->mnt_flag & MNT_SNAPSHOT) {
                if ((mp->mnt_flag & MNT_UPDATE) == 0)
                        return (EINVAL);
                return (ffs_snapshot(mp, fspec));
        }

        /*
         * Must not call namei() while owning busy ref.
         */
        if (mp->mnt_flag & MNT_UPDATE)
                vfs_unbusy(mp);

        /*
         * Not an update, or updating the name: look up the name
         * and verify that it refers to a sensible disk device.
         */
        NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, fspec);
        error = namei(&ndp);
        if ((mp->mnt_flag & MNT_UPDATE) != 0) {
                /*
                 * Unmount does not start if MNT_UPDATE is set.  Mount
                 * update busies mp before setting MNT_UPDATE.  We
                 * must be able to retain our busy ref successfully,
                 * without sleep.
                 */
                error1 = vfs_busy(mp, MBF_NOWAIT);
                MPASS(error1 == 0);
        }
        if (error != 0)
                return (error);
        NDFREE_PNBUF(&ndp);
        if (!vn_isdisk_error(ndp.ni_vp, &error)) {
                vput(ndp.ni_vp);
                return (error);
        }

        /*
         * If mount by non-root, then verify that user has necessary
         * permissions on the device.
         */
        accmode = VREAD;
        if ((mp->mnt_flag & MNT_RDONLY) == 0)
                accmode |= VWRITE;
        error = VOP_ACCESS(ndp.ni_vp, accmode, td->td_ucred, td);
        if (error)
                error = priv_check(td, PRIV_VFS_MOUNT_PERM);
        if (error) {
                vput(ndp.ni_vp);
                return (error);
        }

        /*
         * New mount
         *
         * We need the name for the mount point (also used for
         * "last mounted on") copied in. If an error occurs,
         * the mount point is discarded by the upper level code.
         * Note that vfs_mount_alloc() populates f_mntonname for us.
         */
        if ((mp->mnt_flag & MNT_UPDATE) == 0) {
                if ((error = ffs_mountfs(ndp.ni_vp, mp, td)) != 0) {
                        vrele(ndp.ni_vp);
                        return (error);
                }
        } else {
                /*
                 * When updating, check whether changing from read-only to
                 * read/write; if there is no device name, that's all we do.
                 */
                ump = VFSTOUFS(mp);
                fs = ump->um_fs;
                odevvp = ump->um_odevvp;
                devvp = ump->um_devvp;

                /*
                 * If it's not the same vnode, or at least the same device
                 * then it's not correct.
                 */
                if (ndp.ni_vp->v_rdev != ump->um_odevvp->v_rdev)
                        error = EINVAL; /* needs translation */
                vput(ndp.ni_vp);
                if (error)
                        return (error);
                if (fs->fs_ronly == 0 &&
                    vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
                        /*
                         * Flush any dirty data and suspend filesystem.
                         */
                        if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0)
                                return (error);
                        error = vfs_write_suspend_umnt(mp);
                        if (error != 0)
                                return (error);

                        fs->fs_ronly = 1;
                        if (MOUNTEDSOFTDEP(mp)) {
                                MNT_ILOCK(mp);
                                mp->mnt_flag &= ~MNT_SOFTDEP;
                                MNT_IUNLOCK(mp);
                                mounted_softdep = true;
                        } else
                                mounted_softdep = false;

                        /*
                         * Check for and optionally get rid of files open
                         * for writing.
                         */
                        flags = WRITECLOSE;
                        if (mp->mnt_flag & MNT_FORCE)
                                flags |= FORCECLOSE;
                        if (mounted_softdep) {
                                error = softdep_flushfiles(mp, flags, td);
                        } else {
                                error = ffs_flushfiles(mp, flags, td);
                        }
                        if (error) {
                                fs->fs_ronly = 0;
                                if (mounted_softdep) {
                                        MNT_ILOCK(mp);
                                        mp->mnt_flag |= MNT_SOFTDEP;
                                        MNT_IUNLOCK(mp);
                                }
                                vfs_write_resume(mp, 0);
                                return (error);
                        }

                        if (fs->fs_pendingblocks != 0 ||
                            fs->fs_pendinginodes != 0) {
                                printf("WARNING: %s Update error: blocks %jd "
                                    "files %d\n", fs->fs_fsmnt, 
                                    (intmax_t)fs->fs_pendingblocks,
                                    fs->fs_pendinginodes);
                                fs->fs_pendingblocks = 0;
                                fs->fs_pendinginodes = 0;
                        }
                        if ((fs->fs_flags & (FS_UNCLEAN | FS_NEEDSFSCK)) == 0)
                                fs->fs_clean = 1;
                        if ((error = ffs_sbupdate(ump, MNT_WAIT, 0)) != 0) {
                                fs->fs_ronly = 0;
                                fs->fs_clean = 0;
                                if (mounted_softdep) {
                                        MNT_ILOCK(mp);
                                        mp->mnt_flag |= MNT_SOFTDEP;
                                        MNT_IUNLOCK(mp);
                                }
                                vfs_write_resume(mp, 0);
                                return (error);
                        }
                        if (mounted_softdep)
                                softdep_unmount(mp);
                        g_topology_lock();
                        /*
                         * Drop our write and exclusive access.
                         */
                        g_access(ump->um_cp, 0, -1, -1);
                        g_topology_unlock();
                        MNT_ILOCK(mp);
                        mp->mnt_flag |= MNT_RDONLY;
                        MNT_IUNLOCK(mp);
                        /*
                         * Allow the writers to note that filesystem
                         * is ro now.
                         */
                        vfs_write_resume(mp, 0);
                }
                if ((mp->mnt_flag & MNT_RELOAD) &&
                    (error = ffs_reload(mp, 0)) != 0) {
                        return (error);
                } else {
                        /* ffs_reload replaces the superblock structure */
                        fs = ump->um_fs;
                }
                if (fs->fs_ronly &&
                    !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
                        /*
                         * If upgrade to read-write by non-root, then verify
                         * that user has necessary permissions on the device.
                         */
                        vn_lock(odevvp, LK_EXCLUSIVE | LK_RETRY);
                        error = VOP_ACCESS(odevvp, VREAD | VWRITE,
                            td->td_ucred, td);
                        if (error)
                                error = priv_check(td, PRIV_VFS_MOUNT_PERM);
                        VOP_UNLOCK(odevvp);
                        if (error) {
                                return (error);
                        }
                        /*
                         * Refuse upgrade of NetBSD WAPBL filesystem to
                         * read-write; see validate_sblock() for details.
                         */
                        if (fs->fs_magic == FS_UFS2_MAGIC &&
                            fs->fs_metaspace > fs->fs_fpg / 2) {
                                vfs_mount_error(mp,
                                    "WAPBL filesystem must be mounted read-only");
                                return (EROFS);
                        }
                        fs->fs_flags &= ~FS_UNCLEAN;
                        if (fs->fs_clean == 0) {
                                fs->fs_flags |= FS_UNCLEAN;
                                if ((mp->mnt_flag & MNT_FORCE) ||
                                    ((fs->fs_flags &
                                     (FS_SUJ | FS_NEEDSFSCK)) == 0 &&
                                     (fs->fs_flags & FS_DOSOFTDEP))) {
                                        printf("WARNING: %s was not properly "
                                           "dismounted\n",
                                           mp->mnt_stat.f_mntonname);
                                } else {
                                        vfs_mount_error(mp,
                                           "R/W mount of %s denied. %s.%s",
                                           mp->mnt_stat.f_mntonname,
                                           "Filesystem is not clean - run fsck",
                                           (fs->fs_flags & FS_SUJ) == 0 ? "" :
                                           " Forced mount will invalidate"
                                           " journal contents");
                                        return (EPERM);
                                }
                        }
                        g_topology_lock();
                        /*
                         * Request exclusive write access.
                         */
                        error = g_access(ump->um_cp, 0, 1, 1);
                        g_topology_unlock();
                        if (error)
                                return (error);
                        if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0)
                                return (error);
                        error = vfs_write_suspend_umnt(mp);
                        if (error != 0)
                                return (error);
                        fs->fs_ronly = 0;
                        MNT_ILOCK(mp);
                        saved_mnt_flag = MNT_RDONLY;
                        if (MOUNTEDSOFTDEP(mp) && (mp->mnt_flag &
                            MNT_ASYNC) != 0)
                                saved_mnt_flag |= MNT_ASYNC;
                        mp->mnt_flag &= ~saved_mnt_flag;
                        MNT_IUNLOCK(mp);
                        fs->fs_mtime = time_second;
                        /* check to see if we need to start softdep */
                        if ((fs->fs_flags & FS_DOSOFTDEP) &&
                            (error = softdep_mount(devvp, mp, fs, td->td_ucred))){
                                fs->fs_ronly = 1;
                                MNT_ILOCK(mp);
                                mp->mnt_flag |= saved_mnt_flag;
                                MNT_IUNLOCK(mp);
                                vfs_write_resume(mp, 0);
                                return (error);
                        }
                        fs->fs_clean = 0;
                        if ((error = ffs_sbupdate(ump, MNT_WAIT, 0)) != 0) {
                                fs->fs_ronly = 1;
                                if ((fs->fs_flags & FS_DOSOFTDEP) != 0)
                                        softdep_unmount(mp);
                                MNT_ILOCK(mp);
                                mp->mnt_flag |= saved_mnt_flag;
                                MNT_IUNLOCK(mp);
                                vfs_write_resume(mp, 0);
                                return (error);
                        }
                        if (fs->fs_snapinum[0] != 0)
                                ffs_snapshot_mount(mp);
                        vfs_write_resume(mp, 0);
                }
                /*
                 * Soft updates is incompatible with "async",
                 * so if we are doing softupdates stop the user
                 * from setting the async flag in an update.
                 * Softdep_mount() clears it in an initial mount
                 * or ro->rw remount.
                 */
                if (MOUNTEDSOFTDEP(mp)) {
                        /* XXX: Reset too late ? */
                        MNT_ILOCK(mp);
                        mp->mnt_flag &= ~MNT_ASYNC;
                        MNT_IUNLOCK(mp);
                }
                /*
                 * Keep MNT_ACLS flag if it is stored in superblock.
                 */
                if ((fs->fs_flags & FS_ACLS) != 0) {
                        /* XXX: Set too late ? */
                        MNT_ILOCK(mp);
                        mp->mnt_flag |= MNT_ACLS;
                        MNT_IUNLOCK(mp);
                }

                if ((fs->fs_flags & FS_NFS4ACLS) != 0) {
                        /* XXX: Set too late ? */
                        MNT_ILOCK(mp);
                        mp->mnt_flag |= MNT_NFS4ACLS;
                        MNT_IUNLOCK(mp);
                }

        }

        MNT_ILOCK(mp);
        /*
         * This is racy versus lookup, see ufs_fplookup_vexec for details.
         */
        if ((mp->mnt_kern_flag & MNTK_FPLOOKUP) != 0)
                panic("MNTK_FPLOOKUP set on mount %p when it should not be", mp);
        if ((mp->mnt_flag & (MNT_ACLS | MNT_NFS4ACLS | MNT_UNION)) == 0)
                mp->mnt_kern_flag |= MNTK_FPLOOKUP;
        MNT_IUNLOCK(mp);

        vfs_mountedfrom(mp, fspec);
        return (0);
}

/*
 * Compatibility with old mount system call.
 */

static int
ffs_cmount(struct mntarg *ma, void *data, uint64_t flags)
{
        struct ufs_args args;
        int error;

        if (data == NULL)
                return (EINVAL);
        error = copyin(data, &args, sizeof args);
        if (error)
                return (error);

        ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
        ma = mount_arg(ma, "export", &args.export, sizeof(args.export));
        error = kernel_mount(ma, flags);

        return (error);
}

/*
 * Reload all incore data for a filesystem (used after running fsck on
 * the root filesystem and finding things to fix). If the 'force' flag
 * is 0, 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) If requested, clear MNTK_SUSPEND2 and MNTK_SUSPENDED flags
 *         to allow secondary writers.
 *      4) invalidate all cached file data.
 *      5) re-read inode data for all active vnodes.
 */
int
ffs_reload(struct mount *mp, int flags)
{
        struct vnode *vp, *mvp, *devvp;
        struct inode *ip;
        struct buf *bp;
        struct fs *fs, *newfs;
        struct ufsmount *ump;
        int error;

        ump = VFSTOUFS(mp);

        MNT_ILOCK(mp);
        if ((mp->mnt_flag & MNT_RDONLY) == 0 && (flags & FFSR_FORCE) == 0) {
                MNT_IUNLOCK(mp);
                return (EINVAL);
        }
        MNT_IUNLOCK(mp);

        /*
         * Step 1: invalidate all cached meta-data.
         */
        devvp = VFSTOUFS(mp)->um_devvp;
        vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
        if (vinvalbuf(devvp, 0, 0, 0) != 0)
                panic("ffs_reload: dirty1");
        VOP_UNLOCK(devvp);

        /*
         * Step 2: re-read superblock from disk.
         */
        if ((error = ffs_sbget(devvp, &newfs, UFS_STDSB, 0, M_UFSMNT,
            ffs_use_bread)) != 0)
                return (error);
        /*
         * Replace our superblock with the new superblock. Preserve
         * our read-only status.
         */
        fs = VFSTOUFS(mp)->um_fs;
        newfs->fs_ronly = fs->fs_ronly;
        free(fs->fs_csp, M_UFSMNT);
        free(fs->fs_si, M_UFSMNT);
        free(fs, M_UFSMNT);
        fs = VFSTOUFS(mp)->um_fs = newfs;
        ump->um_bsize = fs->fs_bsize;
        ump->um_maxsymlinklen = fs->fs_maxsymlinklen;
        UFS_LOCK(ump);
        if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
                printf("WARNING: %s: reload pending error: blocks %jd "
                    "files %d\n", mp->mnt_stat.f_mntonname,
                    (intmax_t)fs->fs_pendingblocks, fs->fs_pendinginodes);
                fs->fs_pendingblocks = 0;
                fs->fs_pendinginodes = 0;
        }
        UFS_UNLOCK(ump);
        /*
         * Step 3: If requested, clear MNTK_SUSPEND2 and MNTK_SUSPENDED flags
         * to allow secondary writers.
         */
        if ((flags & FFSR_UNSUSPEND) != 0) {
                MNT_ILOCK(mp);
                mp->mnt_kern_flag &= ~(MNTK_SUSPENDED | MNTK_SUSPEND2);
                wakeup(&mp->mnt_flag);
                MNT_IUNLOCK(mp);
        }

loop:
        MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
                /*
                 * Skip syncer vnode.
                 */
                if (vp->v_type == VNON) {
                        VI_UNLOCK(vp);
                        continue;
                }
                /*
                 * Step 4: invalidate all cached file data.
                 */
                if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK)) {
                        MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
                        goto loop;
                }
                if (vinvalbuf(vp, 0, 0, 0))
                        panic("ffs_reload: dirty2");
                /*
                 * Step 5: re-read inode data for all active vnodes.
                 */
                ip = VTOI(vp);
                error =
                    bread(devvp, fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
                    (int)fs->fs_bsize, NOCRED, &bp);
                if (error) {
                        vput(vp);
                        MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
                        return (error);
                }
                if ((error = ffs_load_inode(bp, ip, fs, ip->i_number)) != 0) {
                        brelse(bp);
                        vput(vp);
                        MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
                        return (error);
                }
                ip->i_effnlink = ip->i_nlink;
                brelse(bp);
                vput(vp);
        }
        return (0);
}

/*
 * Common code for mount and mountroot
 */
static int
ffs_mountfs(struct vnode *odevvp, struct mount *mp, struct thread *td)
{
        struct ufsmount *ump;
        struct fs *fs;
        struct cdev *dev;
        int error, i, len, ronly;
        struct ucred *cred;
        struct g_consumer *cp;
        struct mount *nmp;
        struct vnode *devvp;
        int candelete, canspeedup;

        fs = NULL;
        ump = NULL;
        cred = td ? td->td_ucred : NOCRED;
        ronly = (mp->mnt_flag & MNT_RDONLY) != 0;

        devvp = mntfs_allocvp(mp, odevvp);
        KASSERT(devvp->v_type == VCHR, ("reclaimed devvp"));
        dev = devvp->v_rdev;
        KASSERT(dev->si_snapdata == NULL, ("non-NULL snapshot data"));
        if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0,
            (uintptr_t)mp) == 0) {
                mntfs_freevp(devvp);
                return (EBUSY);
        }
        g_topology_lock();
        error = g_vfs_open(devvp, &cp, "ffs", ronly ? 0 : 1);
        g_topology_unlock();
        if (error != 0) {
                atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0);
                mntfs_freevp(devvp);
                return (error);
        }
        dev_ref(dev);
        devvp->v_bufobj.bo_ops = &ffs_ops;
        BO_LOCK(&odevvp->v_bufobj);
        odevvp->v_bufobj.bo_flag |= BO_NOBUFS;
        BO_UNLOCK(&odevvp->v_bufobj);
        VOP_UNLOCK(devvp);
        if (dev->si_iosize_max != 0)
                mp->mnt_iosize_max = dev->si_iosize_max;
        if (mp->mnt_iosize_max > maxphys)
                mp->mnt_iosize_max = maxphys;
        if ((SBLOCKSIZE % cp->provider->sectorsize) != 0) {
                error = EINVAL;
                vfs_mount_error(mp,
                    "Invalid sectorsize %d for superblock size %d",
                    cp->provider->sectorsize, SBLOCKSIZE);
                goto out;
        }
        /* fetch the superblock and summary information */
        if ((mp->mnt_flag & (MNT_ROOTFS | MNT_FORCE)) != 0)
                error = ffs_sbsearch(devvp, &fs, 0, M_UFSMNT, ffs_use_bread);
        else
                error = ffs_sbget(devvp, &fs, UFS_STDSB, 0, M_UFSMNT,
                    ffs_use_bread);
        if (error != 0)
                goto out;
        /*
         * Per NetBSD's wapbl(4), systems without WAPBL support should mount it
         * read-only; see validate_sblock() for details.
         */
        if (fs->fs_magic == FS_UFS2_MAGIC &&
            fs->fs_metaspace > fs->fs_fpg / 2) {
                if ((mp->mnt_flag & MNT_RDONLY) == 0) {
                        vfs_mount_error(mp,
                            "WAPBL filesystem must be mounted read-only");
                        error = EROFS;
                        goto out;
                }
                printf("WARNING: %s: WAPBL filesystem mounted read-only"
                    "(fs_metaspace %jd, fs_fpg/2 %jd)\n",
                    mp->mnt_stat.f_mntonname, (intmax_t)fs->fs_metaspace,
                    (intmax_t)fs->fs_fpg / 2);
        }
        fs->fs_flags &= ~FS_UNCLEAN;
        if (fs->fs_clean == 0) {
                fs->fs_flags |= FS_UNCLEAN;
                if (ronly || (mp->mnt_flag & MNT_FORCE) ||
                    ((fs->fs_flags & (FS_SUJ | FS_NEEDSFSCK)) == 0 &&
                     (fs->fs_flags & FS_DOSOFTDEP))) {
                        printf("WARNING: %s was not properly dismounted\n",
                            mp->mnt_stat.f_mntonname);
                } else {
                        vfs_mount_error(mp, "R/W mount on %s denied. "
                            "Filesystem is not clean - run fsck.%s",
                            mp->mnt_stat.f_mntonname,
                            (fs->fs_flags & FS_SUJ) == 0 ? "" :
                            " Forced mount will invalidate journal contents");
                        error = EPERM;
                        goto out;
                }
                if ((fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) &&
                    (mp->mnt_flag & MNT_FORCE)) {
                        printf("WARNING: %s: lost blocks %jd files %d\n",
                            mp->mnt_stat.f_mntonname,
                            (intmax_t)fs->fs_pendingblocks,
                            fs->fs_pendinginodes);
                        fs->fs_pendingblocks = 0;
                        fs->fs_pendinginodes = 0;
                }
        }
        if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
                printf("WARNING: %s: mount pending error: blocks %jd "
                    "files %d\n", mp->mnt_stat.f_mntonname,
                    (intmax_t)fs->fs_pendingblocks, fs->fs_pendinginodes);
                fs->fs_pendingblocks = 0;
                fs->fs_pendinginodes = 0;
        }
        if ((fs->fs_flags & FS_GJOURNAL) != 0) {
#ifdef UFS_GJOURNAL
                /*
                 * Get journal provider name.
                 */
                len = 1024;
                mp->mnt_gjprovider = malloc((uint64_t)len, M_UFSMNT, M_WAITOK);
                if (g_io_getattr("GJOURNAL::provider", cp, &len,
                    mp->mnt_gjprovider) == 0) {
                        mp->mnt_gjprovider = realloc(mp->mnt_gjprovider, len,
                            M_UFSMNT, M_WAITOK);
                        MNT_ILOCK(mp);
                        mp->mnt_flag |= MNT_GJOURNAL;
                        MNT_IUNLOCK(mp);
                } else {
                        if ((mp->mnt_flag & MNT_RDONLY) == 0)
                                printf("WARNING: %s: GJOURNAL flag on fs "
                                    "but no gjournal provider below\n",
                                    mp->mnt_stat.f_mntonname);
                        free(mp->mnt_gjprovider, M_UFSMNT);
                        mp->mnt_gjprovider = NULL;
                }
#else
                printf("WARNING: %s: GJOURNAL flag on fs but no "
                    "UFS_GJOURNAL support\n", mp->mnt_stat.f_mntonname);
#endif
        } else {
                mp->mnt_gjprovider = NULL;
        }
        ump = malloc(sizeof *ump, M_UFSMNT, M_WAITOK | M_ZERO);
        ump->um_cp = cp;
        ump->um_bo = &devvp->v_bufobj;
        ump->um_fs = fs;
        if (fs->fs_magic == FS_UFS1_MAGIC) {
                ump->um_fstype = UFS1;
                ump->um_balloc = ffs_balloc_ufs1;
        } else {
                ump->um_fstype = UFS2;
                ump->um_balloc = ffs_balloc_ufs2;
        }
        ump->um_blkatoff = ffs_blkatoff;
        ump->um_truncate = ffs_truncate;
        ump->um_update = ffs_update;
        ump->um_valloc = ffs_valloc;
        ump->um_vfree = ffs_vfree;
        ump->um_ifree = ffs_ifree;
        ump->um_rdonly = ffs_rdonly;
        ump->um_snapgone = ffs_snapgone;
        if ((mp->mnt_flag & MNT_UNTRUSTED) != 0)
                ump->um_check_blkno = ffs_check_blkno;
        else
                ump->um_check_blkno = NULL;
        mtx_init(UFS_MTX(ump), "FFS", "FFS Lock", MTX_DEF);
        fs->fs_ronly = ronly;
        fs->fs_active = NULL;
        mp->mnt_data = ump;
        mp->mnt_stat.f_fsid.val[0] = fs->fs_id[0];
        mp->mnt_stat.f_fsid.val[1] = fs->fs_id[1];
        nmp = NULL;
        if (fs->fs_id[0] == 0 || fs->fs_id[1] == 0 ||
            (nmp = vfs_getvfs(&mp->mnt_stat.f_fsid))) {
                if (nmp)
                        vfs_rel(nmp);
                vfs_getnewfsid(mp);
        }
        ump->um_bsize = fs->fs_bsize;
        ump->um_maxsymlinklen = fs->fs_maxsymlinklen;
        MNT_ILOCK(mp);
        mp->mnt_flag |= MNT_LOCAL;
        MNT_IUNLOCK(mp);
        if ((fs->fs_flags & FS_MULTILABEL) != 0) {
#ifdef MAC
                MNT_ILOCK(mp);
                mp->mnt_flag |= MNT_MULTILABEL;
                MNT_IUNLOCK(mp);
#else
                printf("WARNING: %s: multilabel flag on fs but "
                    "no MAC support\n", mp->mnt_stat.f_mntonname);
#endif
        }
        if ((fs->fs_flags & FS_ACLS) != 0) {
#ifdef UFS_ACL
                MNT_ILOCK(mp);

                if (mp->mnt_flag & MNT_NFS4ACLS)
                        printf("WARNING: %s: ACLs flag on fs conflicts with "
                            "\"nfsv4acls\" mount option; option ignored\n",
                            mp->mnt_stat.f_mntonname);
                mp->mnt_flag &= ~MNT_NFS4ACLS;
                mp->mnt_flag |= MNT_ACLS;

                MNT_IUNLOCK(mp);
#else
                printf("WARNING: %s: ACLs flag on fs but no ACLs support\n",
                    mp->mnt_stat.f_mntonname);
#endif
        }
        if ((fs->fs_flags & FS_NFS4ACLS) != 0) {
#ifdef UFS_ACL
                MNT_ILOCK(mp);

                if (mp->mnt_flag & MNT_ACLS)
                        printf("WARNING: %s: NFSv4 ACLs flag on fs conflicts "
                            "with \"acls\" mount option; option ignored\n",
                            mp->mnt_stat.f_mntonname);
                mp->mnt_flag &= ~MNT_ACLS;
                mp->mnt_flag |= MNT_NFS4ACLS;

                MNT_IUNLOCK(mp);
#else
                printf("WARNING: %s: NFSv4 ACLs flag on fs but no "
                    "ACLs support\n", mp->mnt_stat.f_mntonname);
#endif
        }
        if ((fs->fs_flags & FS_TRIM) != 0) {
                len = sizeof(int);
                if (g_io_getattr("GEOM::candelete", cp, &len,
                    &candelete) == 0) {
                        if (candelete)
                                ump->um_flags |= UM_CANDELETE;
                        else
                                printf("WARNING: %s: TRIM flag on fs but disk "
                                    "does not support TRIM\n",
                                    mp->mnt_stat.f_mntonname);
                } else {
                        printf("WARNING: %s: TRIM flag on fs but disk does "
                            "not confirm that it supports TRIM\n",
                            mp->mnt_stat.f_mntonname);
                }
                if (((ump->um_flags) & UM_CANDELETE) != 0) {
                        ump->um_trim_tq = taskqueue_create("trim", M_WAITOK,
                            taskqueue_thread_enqueue, &ump->um_trim_tq);
                        taskqueue_start_threads(&ump->um_trim_tq, 1, PVFS,
                            "%s trim", mp->mnt_stat.f_mntonname);
                        ump->um_trimhash = hashinit(MAXTRIMIO, M_TRIM,
                            &ump->um_trimlisthashsize);
                }
        }

        len = sizeof(int);
        if (g_io_getattr("GEOM::canspeedup", cp, &len, &canspeedup) == 0) {
                if (canspeedup)
                        ump->um_flags |= UM_CANSPEEDUP;
        }

        ump->um_mountp = mp;
        ump->um_dev = dev;
        ump->um_devvp = devvp;
        ump->um_odevvp = odevvp;
        ump->um_nindir = fs->fs_nindir;
        ump->um_bptrtodb = fs->fs_fsbtodb;
        ump->um_seqinc = fs->fs_frag;
        for (i = 0; i < MAXQUOTAS; i++)
                ump->um_quotas[i] = NULL;
#ifdef UFS_EXTATTR
        ufs_extattr_uepm_init(&ump->um_extattr);
#endif
        /*
         * Set FS local "last mounted on" information (NULL pad)
         */
        bzero(fs->fs_fsmnt, MAXMNTLEN);
        strlcpy(fs->fs_fsmnt, mp->mnt_stat.f_mntonname, MAXMNTLEN);
        mp->mnt_stat.f_iosize = fs->fs_bsize;

        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;
        }

        if (ronly == 0) {
                fs->fs_mtime = time_second;
                if ((fs->fs_flags & FS_DOSOFTDEP) &&
                    (error = softdep_mount(devvp, mp, fs, cred)) != 0) {
                        ffs_flushfiles(mp, FORCECLOSE, td);
                        goto out;
                }
                if (fs->fs_snapinum[0] != 0)
                        ffs_snapshot_mount(mp);
                fs->fs_fmod = 1;
                fs->fs_clean = 0;
                (void) ffs_sbupdate(ump, MNT_WAIT, 0);
        }
        /*
         * Initialize filesystem state information in mount struct.
         */
        MNT_ILOCK(mp);
        mp->mnt_kern_flag |= MNTK_LOOKUP_SHARED | MNTK_EXTENDED_SHARED |
            MNTK_NO_IOPF | MNTK_UNMAPPED_BUFS | MNTK_USES_BCACHE;
        MNT_IUNLOCK(mp);
#ifdef UFS_EXTATTR
#ifdef UFS_EXTATTR_AUTOSTART
        /*
         *
         * Auto-starting does the following:
         *      - check for /.attribute in the fs, and extattr_start if so
         *      - for each file in .attribute, enable that file with
         *        an attribute of the same name.
         * Not clear how to report errors -- probably eat them.
         * This would all happen while the filesystem was busy/not
         * available, so would effectively be "atomic".
         */
        (void) ufs_extattr_autostart(mp, td);
#endif /* !UFS_EXTATTR_AUTOSTART */
#endif /* !UFS_EXTATTR */
        return (0);
out:
        if (fs != NULL) {
                free(fs->fs_csp, M_UFSMNT);
                free(fs->fs_si, M_UFSMNT);
                free(fs, M_UFSMNT);
        }
        if (cp != NULL) {
                g_topology_lock();
                g_vfs_close(cp);
                g_topology_unlock();
        }
        if (ump != NULL) {
                mtx_destroy(UFS_MTX(ump));
                if (mp->mnt_gjprovider != NULL) {
                        free(mp->mnt_gjprovider, M_UFSMNT);
                        mp->mnt_gjprovider = NULL;
                }
                MPASS(ump->um_softdep == NULL);
                free(ump, M_UFSMNT);
                mp->mnt_data = NULL;
        }
        BO_LOCK(&odevvp->v_bufobj);
        odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS;
        BO_UNLOCK(&odevvp->v_bufobj);
        atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0);
        vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
        mntfs_freevp(devvp);
        dev_rel(dev);
        return (error);
}

/*
 * A read function for use by filesystem-layer routines.
 */
static int
ffs_use_bread(void *devfd, off_t loc, void **bufp, int size)
{
        struct buf *bp;
        int error;

        KASSERT(*bufp == NULL, ("ffs_use_bread: non-NULL *bufp %p\n", *bufp));
        *bufp = malloc(size, M_UFSMNT, M_WAITOK);
        if ((error = bread((struct vnode *)devfd, btodb(loc), size, NOCRED,
            &bp)) != 0)
                return (error);
        bcopy(bp->b_data, *bufp, size);
        bp->b_flags |= B_INVAL | B_NOCACHE;
        brelse(bp);
        return (0);
}

/*
 * unmount system call
 */
static int
ffs_unmount(struct mount *mp, int mntflags)
{
        struct thread *td;
        struct ufsmount *ump = VFSTOUFS(mp);
        struct fs *fs;
        int error, flags, susp;
#ifdef UFS_EXTATTR
        int e_restart;
#endif

        flags = 0;
        td = curthread;
        fs = ump->um_fs;
        if (mntflags & MNT_FORCE)
                flags |= FORCECLOSE;
        susp = fs->fs_ronly == 0;
#ifdef UFS_EXTATTR
        if ((error = ufs_extattr_stop(mp, td))) {
                if (error != EOPNOTSUPP)
                        printf("WARNING: unmount %s: ufs_extattr_stop "
                            "returned errno %d\n", mp->mnt_stat.f_mntonname,
                            error);
                e_restart = 0;
        } else {
                ufs_extattr_uepm_destroy(&ump->um_extattr);
                e_restart = 1;
        }
#endif
        if (susp) {
                error = vfs_write_suspend_umnt(mp);
                if (error != 0)
                        goto fail1;
        }
        if (MOUNTEDSOFTDEP(mp))
                error = softdep_flushfiles(mp, flags, td);
        else
                error = ffs_flushfiles(mp, flags, td);
        if (error != 0 && !ffs_fsfail_cleanup(ump, error))
                goto fail;

        UFS_LOCK(ump);
        if (fs->fs_pendingblocks != 0 || fs->fs_pendinginodes != 0) {
                printf("WARNING: unmount %s: pending error: blocks %jd "
                    "files %d\n", fs->fs_fsmnt, (intmax_t)fs->fs_pendingblocks,
                    fs->fs_pendinginodes);
                fs->fs_pendingblocks = 0;
                fs->fs_pendinginodes = 0;
        }
        UFS_UNLOCK(ump);
        if (MOUNTEDSOFTDEP(mp))
                softdep_unmount(mp);
        MPASS(ump->um_softdep == NULL);
        if (fs->fs_ronly == 0) {
                fs->fs_clean = fs->fs_flags & (FS_UNCLEAN|FS_NEEDSFSCK) ? 0 : 1;
                error = ffs_sbupdate(ump, MNT_WAIT, 0);
                if (ffs_fsfail_cleanup(ump, error))
                        error = 0;
                if (error != 0 && !ffs_fsfail_cleanup(ump, error)) {
                        fs->fs_clean = 0;
                        goto fail;
                }
        }
        if (susp)
                vfs_write_resume(mp, VR_START_WRITE);
        if (ump->um_trim_tq != NULL) {
                MPASS(ump->um_trim_inflight == 0);
                taskqueue_free(ump->um_trim_tq);
                free (ump->um_trimhash, M_TRIM);
        }
        vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
        g_topology_lock();
        g_vfs_close(ump->um_cp);
        g_topology_unlock();
        BO_LOCK(&ump->um_odevvp->v_bufobj);
        ump->um_odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS;
        BO_UNLOCK(&ump->um_odevvp->v_bufobj);
        atomic_store_rel_ptr((uintptr_t *)&ump->um_dev->si_mountpt, 0);
        mntfs_freevp(ump->um_devvp);
        vrele(ump->um_odevvp);
        dev_rel(ump->um_dev);
        mtx_destroy(UFS_MTX(ump));
        if (mp->mnt_gjprovider != NULL) {
                free(mp->mnt_gjprovider, M_UFSMNT);
                mp->mnt_gjprovider = NULL;
        }
        free(fs->fs_csp, M_UFSMNT);
        free(fs->fs_si, M_UFSMNT);
        free(fs, M_UFSMNT);
        free(ump, M_UFSMNT);
        mp->mnt_data = NULL;
        if (td->td_su == mp) {
                td->td_su = NULL;
                vfs_rel(mp);
        }
        return (error);

fail:
        if (susp)
                vfs_write_resume(mp, VR_START_WRITE);
fail1:
#ifdef UFS_EXTATTR
        if (e_restart) {
                ufs_extattr_uepm_init(&ump->um_extattr);
#ifdef UFS_EXTATTR_AUTOSTART
                (void) ufs_extattr_autostart(mp, td);
#endif
        }
#endif

        return (error);
}

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

        ump = VFSTOUFS(mp);
        qerror = 0;
#ifdef QUOTA
        if (mp->mnt_flag & MNT_QUOTA) {
                int i;
                error = vflush(mp, 0, SKIPSYSTEM|flags, td);
                if (error)
                        return (error);
                for (i = 0; i < MAXQUOTAS; i++) {
                        error = quotaoff(td, mp, i);
                        if (error != 0) {
                                if ((flags & EARLYFLUSH) == 0)
                                        return (error);
                                else
                                        qerror = error;
                        }
                }

                /*
                 * Here we fall through to vflush again to ensure that
                 * we have gotten rid of all the system vnodes, unless
                 * quotas must not be closed.
                 */
        }
#endif
        /* devvp is not locked there */
        if (ump->um_devvp->v_vflag & VV_COPYONWRITE) {
                if ((error = vflush(mp, 0, SKIPSYSTEM | flags, td)) != 0)
                        return (error);
                ffs_snapshot_unmount(mp);
                flags |= FORCECLOSE;
                /*
                 * Here we fall through to vflush again to ensure
                 * that we have gotten rid of all the system vnodes.
                 */
        }

        /*
         * Do not close system files if quotas were not closed, to be
         * able to sync the remaining dquots.  The freeblks softupdate
         * workitems might hold a reference on a dquot, preventing
         * quotaoff() from completing.  Next round of
         * softdep_flushworklist() iteration should process the
         * blockers, allowing the next run of quotaoff() to finally
         * flush held dquots.
         *
         * Otherwise, flush all the files.
         */
        if (qerror == 0 && (error = vflush(mp, 0, flags, td)) != 0)
                return (error);

        /*
         * If this is a forcible unmount and there were any files that
         * were unlinked but still open, then vflush() will have
         * truncated and freed those files, which might have started
         * some trim work.  Wait here for any trims to complete
         * and process the blkfrees which follow the trims.
         * This may create more dirty devvp buffers and softdep deps.
         */
        if (ump->um_trim_tq != NULL) {
                while (ump->um_trim_inflight != 0)
                        pause("ufsutr", hz);
                taskqueue_drain_all(ump->um_trim_tq);
        }

        /*
         * Flush filesystem metadata.
         */
        vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
        error = VOP_FSYNC(ump->um_devvp, MNT_WAIT, td);
        VOP_UNLOCK(ump->um_devvp);
        return (error);
}

/*
 * Get filesystem statistics.
 */
static int
ffs_statfs(struct mount *mp, struct statfs *sbp)
{
        struct ufsmount *ump;
        struct fs *fs;

        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        if (fs->fs_magic != FS_UFS1_MAGIC && fs->fs_magic != FS_UFS2_MAGIC)
                panic("ffs_statfs");
        sbp->f_version = STATFS_VERSION;
        sbp->f_bsize = fs->fs_fsize;
        sbp->f_iosize = fs->fs_bsize;
        sbp->f_blocks = fs->fs_dsize;
        UFS_LOCK(ump);
        sbp->f_bfree = fs->fs_cstotal.cs_nbfree * fs->fs_frag +
            fs->fs_cstotal.cs_nffree + dbtofsb(fs, fs->fs_pendingblocks);
        sbp->f_bavail = freespace(fs, fs->fs_minfree) +
            dbtofsb(fs, fs->fs_pendingblocks);
        sbp->f_files =  fs->fs_ncg * fs->fs_ipg - UFS_ROOTINO;
        sbp->f_ffree = fs->fs_cstotal.cs_nifree + fs->fs_pendinginodes;
        UFS_UNLOCK(ump);
        sbp->f_namemax = UFS_MAXNAMLEN;
        return (0);
}

static bool
sync_doupdate(struct inode *ip)
{

        return ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED |
            IN_UPDATE)) != 0);
}

static int
ffs_sync_lazy_filter(struct vnode *vp, void *arg __unused)
{
        struct inode *ip;

        /*
         * Flags are safe to access because ->v_data invalidation
         * is held off by listmtx.
         */
        if (vp->v_type == VNON)
                return (false);
        ip = VTOI(vp);
        if (!sync_doupdate(ip) && (vp->v_iflag & VI_OWEINACT) == 0)
                return (false);
        return (true);
}

/*
 * For a lazy sync, we only care about access times, quotas and the
 * superblock.  Other filesystem changes are already converted to
 * cylinder group blocks or inode blocks updates and are written to
 * disk by syncer.
 */
static int
ffs_sync_lazy(struct mount *mp)
{
        struct vnode *mvp, *vp;
        struct inode *ip;
        int allerror, error;

        allerror = 0;
        if ((mp->mnt_flag & MNT_NOATIME) != 0) {
#ifdef QUOTA
                qsync(mp);
#endif
                goto sbupdate;
        }
        MNT_VNODE_FOREACH_LAZY(vp, mp, mvp, ffs_sync_lazy_filter, NULL) {
                if (vp->v_type == VNON) {
                        VI_UNLOCK(vp);
                        continue;
                }
                ip = VTOI(vp);

                /*
                 * The IN_ACCESS flag is converted to IN_MODIFIED by
                 * ufs_close() and ufs_getattr() by the calls to
                 * ufs_itimes_locked(), without subsequent UFS_UPDATE().
                 * Test also all the other timestamp flags too, to pick up
                 * any other cases that could be missed.
                 */
                if (!sync_doupdate(ip) && (vp->v_iflag & VI_OWEINACT) == 0) {
                        VI_UNLOCK(vp);
                        continue;
                }
                if ((error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK)) != 0)
                        continue;
#ifdef QUOTA
                qsyncvp(vp);
#endif
                if (sync_doupdate(ip))
                        error = ffs_update(vp, 0);
                if (error != 0)
                        allerror = error;
                vput(vp);
        }
sbupdate:
        if (VFSTOUFS(mp)->um_fs->fs_fmod != 0 &&
            (error = ffs_sbupdate(VFSTOUFS(mp), MNT_LAZY, 0)) != 0)
                allerror = error;
        return (allerror);
}

/*
 * 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 busy using
 * vfs_busy().
 */
static int
ffs_sync(struct mount *mp, int waitfor)
{
        struct vnode *mvp, *vp, *devvp;
        struct thread *td;
        struct inode *ip;
        struct ufsmount *ump = VFSTOUFS(mp);
        struct fs *fs;
        int error, count, lockreq, allerror = 0;
        int suspend;
        int suspended;
        int secondary_writes;
        int secondary_accwrites;
        int softdep_deps;
        int softdep_accdeps;
        struct bufobj *bo;

        suspend = 0;
        suspended = 0;
        td = curthread;
        fs = ump->um_fs;
        if (fs->fs_fmod != 0 && fs->fs_ronly != 0)
                panic("%s: ffs_sync: modification on read-only filesystem",
                    fs->fs_fsmnt);
        if (waitfor == MNT_LAZY) {
                if (!rebooting)
                        return (ffs_sync_lazy(mp));
                waitfor = MNT_NOWAIT;
        }

        /*
         * Write back each (modified) inode.
         */
        lockreq = LK_EXCLUSIVE | LK_NOWAIT;
        if (waitfor == MNT_SUSPEND) {
                suspend = 1;
                waitfor = MNT_WAIT;
        }
        if (waitfor == MNT_WAIT)
                lockreq = LK_EXCLUSIVE;
        lockreq |= LK_INTERLOCK;
loop:
        /* Grab snapshot of secondary write counts */
        MNT_ILOCK(mp);
        secondary_writes = mp->mnt_secondary_writes;
        secondary_accwrites = mp->mnt_secondary_accwrites;
        MNT_IUNLOCK(mp);

        /* Grab snapshot of softdep dependency counts */
        softdep_get_depcounts(mp, &softdep_deps, &softdep_accdeps);

        MNT_VNODE_FOREACH_ALL(vp, mp, mvp) {
                /*
                 * Depend on the vnode interlock to keep things stable enough
                 * for a quick test.  Since there might be hundreds of
                 * thousands of vnodes, we cannot afford even a subroutine
                 * call unless there's a good chance that we have work to do.
                 */
                if (vp->v_type == VNON) {
                        VI_UNLOCK(vp);
                        continue;
                }
                ip = VTOI(vp);
                if ((ip->i_flag &
                    (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE)) == 0 &&
                    vp->v_bufobj.bo_dirty.bv_cnt == 0) {
                        VI_UNLOCK(vp);
                        continue;
                }
                if ((error = vget(vp, lockreq)) != 0) {
                        if (error == ENOENT) {
                                MNT_VNODE_FOREACH_ALL_ABORT(mp, mvp);
                                goto loop;
                        }
                        continue;
                }
#ifdef QUOTA
                qsyncvp(vp);
#endif
                for (;;) {
                        error = ffs_syncvnode(vp, waitfor, 0);
                        if (error == ERELOOKUP)
                                continue;
                        if (error != 0)
                                allerror = error;
                        break;
                }
                vput(vp);
        }
        /*
         * Force stale filesystem control information to be flushed.
         */
        if (waitfor == MNT_WAIT || rebooting) {
                if ((error = softdep_flushworklist(ump->um_mountp, &count, td)))
                        allerror = error;
                if (ffs_fsfail_cleanup(ump, allerror))
                        allerror = 0;
                /* Flushed work items may create new vnodes to clean */
                if (allerror == 0 && count)
                        goto loop;
        }

        devvp = ump->um_devvp;
        bo = &devvp->v_bufobj;
        BO_LOCK(bo);
        if (bo->bo_numoutput > 0 || bo->bo_dirty.bv_cnt > 0) {
                BO_UNLOCK(bo);
                vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
                error = VOP_FSYNC(devvp, waitfor, td);
                VOP_UNLOCK(devvp);
                if (MOUNTEDSOFTDEP(mp) && (error == 0 || error == EAGAIN))
                        error = ffs_sbupdate(ump, waitfor, 0);
                if (error != 0)
                        allerror = error;
                if (ffs_fsfail_cleanup(ump, allerror))
                        allerror = 0;
                if (allerror == 0 && waitfor == MNT_WAIT)
                        goto loop;
        } else if (suspend != 0) {
                if (softdep_check_suspend(mp,
                                          devvp,
                                          softdep_deps,
                                          softdep_accdeps,
                                          secondary_writes,
                                          secondary_accwrites) != 0) {
                        MNT_IUNLOCK(mp);
                        goto loop;      /* More work needed */
                }
                mtx_assert(MNT_MTX(mp), MA_OWNED);
                mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED;
                MNT_IUNLOCK(mp);
                suspended = 1;
        } else
                BO_UNLOCK(bo);
        /*
         * Write back modified superblock.
         */
        if (fs->fs_fmod != 0 &&
            (error = ffs_sbupdate(ump, waitfor, suspended)) != 0)
                allerror = error;
        if (ffs_fsfail_cleanup(ump, allerror))
                allerror = 0;
        return (allerror);
}

int
ffs_vget(struct mount *mp, ino_t ino, int flags, struct vnode **vpp)
{
        return (ffs_vgetf(mp, ino, flags, vpp, 0));
}

int
ffs_vgetf(struct mount *mp,
        ino_t ino,
        int flags,
        struct vnode **vpp,
        int ffs_flags)
{
        struct fs *fs;
        struct inode *ip;
        struct ufsmount *ump;
        struct buf *bp;
        struct vnode *vp;
        daddr_t dbn;
        int error;

        MPASS((ffs_flags & (FFSV_REPLACE | FFSV_REPLACE_DOOMED)) == 0 ||
            (flags & LK_EXCLUSIVE) != 0);

        error = vfs_hash_get(mp, ino, flags, curthread, vpp, NULL, NULL);
        if (error != 0)
                return (error);
        if (*vpp != NULL) {
                if ((ffs_flags & FFSV_REPLACE) == 0 ||
                    ((ffs_flags & FFSV_REPLACE_DOOMED) == 0 ||
                    !VN_IS_DOOMED(*vpp)))
                        return (0);
                vgone(*vpp);
                vput(*vpp);
        }

        /*
         * We must promote to an exclusive lock for vnode creation.  This
         * can happen if lookup is passed LOCKSHARED.
         */
        if ((flags & LK_TYPE_MASK) == LK_SHARED) {
                flags &= ~LK_TYPE_MASK;
                flags |= LK_EXCLUSIVE;
        }

        /*
         * We do not lock vnode creation as it is believed to be too
         * expensive for such rare case as simultaneous creation of vnode
         * for same ino by different processes. We just allow them to race
         * and check later to decide who wins. Let the race begin!
         */

        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        ip = uma_zalloc_smr(uma_inode, M_WAITOK | M_ZERO);

        /* Allocate a new vnode/inode. */
        error = getnewvnode("ufs", mp, fs->fs_magic == FS_UFS1_MAGIC ?
            &ffs_vnodeops1 : &ffs_vnodeops2, &vp);
        if (error) {
                *vpp = NULL;
                uma_zfree_smr(uma_inode, ip);
                return (error);
        }
        /*
         * FFS supports recursive locking.
         */
        lockmgr(vp->v_vnlock, LK_EXCLUSIVE | LK_NOWITNESS, NULL);
        VN_LOCK_AREC(vp);
        vp->v_data = ip;
        vp->v_bufobj.bo_bsize = fs->fs_bsize;
        ip->i_vnode = vp;
        ip->i_ump = ump;
        ip->i_number = ino;
        ip->i_ea_refs = 0;
        ip->i_nextclustercg = -1;
        ip->i_flag = fs->fs_magic == FS_UFS1_MAGIC ? 0 : IN_UFS2;
        ip->i_mode = 0; /* ensure error cases below throw away vnode */
        cluster_init_vn(&ip->i_clusterw);
#ifdef DIAGNOSTIC
        ufs_init_trackers(ip);
#endif
#ifdef QUOTA
        {
                int i;
                for (i = 0; i < MAXQUOTAS; i++)
                        ip->i_dquot[i] = NODQUOT;
        }
#endif

        if (ffs_flags & FFSV_FORCEINSMQ)
                vp->v_vflag |= VV_FORCEINSMQ;
        error = insmntque(vp, mp);
        if (error != 0) {
                uma_zfree_smr(uma_inode, ip);
                *vpp = NULL;
                return (error);
        }
        vp->v_vflag &= ~VV_FORCEINSMQ;
        error = vfs_hash_insert(vp, ino, flags, curthread, vpp, NULL, NULL);
        if (error != 0)
                return (error);
        if (*vpp != NULL) {
                /*
                 * Calls from ffs_valloc() (i.e. FFSV_REPLACE set)
                 * operate on empty inode, which must not be found by
                 * other threads until fully filled.  Vnode for empty
                 * inode must be not re-inserted on the hash by other
                 * thread, after removal by us at the beginning.
                 */
                MPASS((ffs_flags & FFSV_REPLACE) == 0);
                return (0);
        }
        if (I_IS_UFS1(ip))
                ip->i_din1 = uma_zalloc(uma_ufs1, M_WAITOK);
        else
                ip->i_din2 = uma_zalloc(uma_ufs2, M_WAITOK);

        if ((ffs_flags & FFSV_NEWINODE) != 0) {
                /* New inode, just zero out its contents. */
                if (I_IS_UFS1(ip))
                        memset(ip->i_din1, 0, sizeof(struct ufs1_dinode));
                else
                        memset(ip->i_din2, 0, sizeof(struct ufs2_dinode));
        } else {
                /* Read the disk contents for the inode, copy into the inode. */
                dbn = fsbtodb(fs, ino_to_fsba(fs, ino));
                error = ffs_breadz(ump, ump->um_devvp, dbn, dbn,
                    (int)fs->fs_bsize, NULL, NULL, 0, NOCRED, 0, NULL, &bp);
                if (error != 0) {
                        /*
                         * 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().
                         */
                        vgone(vp);
                        vput(vp);
                        *vpp = NULL;
                        return (error);
                }
                if ((error = ffs_load_inode(bp, ip, fs, ino)) != 0) {
                        bqrelse(bp);
                        vgone(vp);
                        vput(vp);
                        *vpp = NULL;
                        return (error);
                }
                bqrelse(bp);
        }
        if (DOINGSOFTDEP(vp) && (!fs->fs_ronly ||
            (ffs_flags & FFSV_FORCEINODEDEP) != 0))
                softdep_load_inodeblock(ip);
        else
                ip->i_effnlink = ip->i_nlink;

        /*
         * Initialize the vnode from the inode, check for aliases.
         * Note that the underlying vnode may have changed.
         */
        error = ufs_vinit(mp, I_IS_UFS1(ip) ? &ffs_fifoops1 : &ffs_fifoops2,
            &vp);
        if (error) {
                vgone(vp);
                vput(vp);
                *vpp = NULL;
                return (error);
        }

        /*
         * Finish inode initialization.
         */
        if (vp->v_type != VFIFO) {
                /* FFS supports shared locking for all files except fifos. */
                VN_LOCK_ASHARE(vp);
        }

        /*
         * 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) {
                while (ip->i_gen == 0)
                        ip->i_gen = arc4random();
                if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
                        UFS_INODE_SET_FLAG(ip, IN_MODIFIED);
                        DIP_SET(ip, i_gen, ip->i_gen);
                }
        }
#ifdef MAC
        if ((mp->mnt_flag & MNT_MULTILABEL) && ip->i_mode) {
                /*
                 * If this vnode is already allocated, and we're running
                 * multi-label, attempt to perform a label association
                 * from the extended attributes on the inode.
                 */
                error = mac_vnode_associate_extattr(mp, vp);
                if (error) {
                        /* ufs_inactive will release ip->i_devvp ref. */
                        vgone(vp);
                        vput(vp);
                        *vpp = NULL;
                        return (error);
                }
        }
#endif

        vn_set_state(vp, VSTATE_CONSTRUCTED);
        *vpp = vp;
        return (0);
}

/*
 * File handle to vnode
 *
 * Have to be really careful about stale file handles:
 * - check that the inode number is valid
 * - for UFS2 check that the inode number is initialized
 * - call ffs_vget() to get the locked inode
 * - check for an unallocated inode (i_mode == 0)
 * - check that the given client host has export rights and return
 *   those rights via. exflagsp and credanonp
 */
static int
ffs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
{
        struct ufid *ufhp;

        ufhp = (struct ufid *)fhp;
        return (ffs_inotovp(mp, ufhp->ufid_ino, ufhp->ufid_gen, flags,
            vpp, 0));
}

/*
 * Return a vnode from a mounted filesystem for inode with specified
 * generation number. Return ESTALE if the inode with given generation
 * number no longer exists on that filesystem.
 */
int
ffs_inotovp(struct mount *mp,
        ino_t ino,
        uint64_t gen,
        int lflags,
        struct vnode **vpp,
        int ffs_flags)
{
        struct ufsmount *ump;
        struct vnode *nvp;
        struct inode *ip;
        struct fs *fs;
        struct cg *cgp;
        struct buf *bp;
        uint64_t cg;

        ump = VFSTOUFS(mp);
        fs = ump->um_fs;
        *vpp = NULL;

        if (ino < UFS_ROOTINO || ino >= fs->fs_ncg * fs->fs_ipg)
                return (ESTALE);

        /*
         * Need to check if inode is initialized because UFS2 does lazy
         * initialization and nfs_fhtovp can offer arbitrary inode numbers.
         */
        if (fs->fs_magic == FS_UFS2_MAGIC) {
                cg = ino_to_cg(fs, ino);
                if (ffs_getcg(fs, ump->um_devvp, cg, 0, &bp, &cgp) != 0)
                        return (ESTALE);
                if (ino >= cg * fs->fs_ipg + cgp->cg_initediblk) {
                        brelse(bp);
                        return (ESTALE);
                }
                brelse(bp);
        }

        if (ffs_vgetf(mp, ino, lflags, &nvp, ffs_flags) != 0)
                return (ESTALE);

        ip = VTOI(nvp);
        if (ip->i_mode == 0 || ip->i_gen != gen) {
                if (ip->i_mode == 0)
                        vgone(nvp);
                vput(nvp);
                return (ESTALE);
        }

        vnode_create_vobject(nvp, DIP(ip, i_size), curthread);
        *vpp = nvp;
        return (0);
}

/*
 * Initialize the filesystem.
 */
static int
ffs_init(struct vfsconf *vfsp)
{

        ffs_susp_initialize();
        softdep_initialize();
        return (ufs_init(vfsp));
}

/*
 * Undo the work of ffs_init().
 */
static int
ffs_uninit(struct vfsconf *vfsp)
{
        int ret;

        ret = ufs_uninit(vfsp);
        softdep_uninitialize();
        ffs_susp_uninitialize();
        taskqueue_drain_all(taskqueue_thread);
        return (ret);
}

/*
 * Structure used to pass information from ffs_sbupdate to its
 * helper routine ffs_use_bwrite.
 */
struct devfd {
        struct ufsmount *ump;
        struct buf      *sbbp;
        int              waitfor;
        int              suspended;
        int              error;
};

/*
 * Write a superblock and associated information back to disk.
 */
int
ffs_sbupdate(struct ufsmount *ump, int waitfor, int suspended)
{
        struct fs *fs;
        struct buf *sbbp;
        struct devfd devfd;

        fs = ump->um_fs;
        if (fs->fs_ronly == 1 &&
            (ump->um_mountp->mnt_flag & (MNT_RDONLY | MNT_UPDATE)) !=
            (MNT_RDONLY | MNT_UPDATE))
                panic("ffs_sbupdate: write read-only filesystem");
        /*
         * We use the superblock's buf to serialize calls to ffs_sbupdate().
         * Copy superblock to this buffer and have it written out.
         */
        sbbp = getblk(ump->um_devvp, btodb(fs->fs_sblockloc),
            (int)fs->fs_sbsize, 0, 0, 0);
        UFS_LOCK(ump);
        fs->fs_fmod = 0;
        bcopy((caddr_t)fs, sbbp->b_data, (uint64_t)fs->fs_sbsize);
        UFS_UNLOCK(ump);
        fs = (struct fs *)sbbp->b_data;
        /*
         * Initialize info needed for write function.
         */
        devfd.ump = ump;
        devfd.sbbp = sbbp;
        devfd.waitfor = waitfor;
        devfd.suspended = suspended;
        devfd.error = 0;
        return (ffs_sbput(&devfd, fs, fs->fs_sblockloc, ffs_use_bwrite));
}

/*
 * Write function for use by filesystem-layer routines.
 */
static int
ffs_use_bwrite(void *devfd, off_t loc, void *buf, int size)
{
        struct devfd *devfdp;
        struct ufsmount *ump;
        struct buf *bp;
        struct fs *fs;
        int error;

        devfdp = devfd;
        ump = devfdp->ump;
        bp = devfdp->sbbp;
        fs = (struct fs *)bp->b_data;
        /*
         * Writing the superblock summary information.
         */
        if (loc != fs->fs_sblockloc) {
                bp = getblk(ump->um_devvp, btodb(loc), size, 0, 0, 0);
                bcopy(buf, bp->b_data, (uint64_t)size);
                if (devfdp->suspended)
                        bp->b_flags |= B_VALIDSUSPWRT;
                if (devfdp->waitfor != MNT_WAIT)
                        bawrite(bp);
                else if ((error = bwrite(bp)) != 0)
                        devfdp->error = error;
                return (0);
        }
        /*
         * Writing the superblock itself. We need to do special checks for it.
         * A negative error code is returned to indicate that a copy of the
         * superblock has been made and that the copy is discarded when the
         * I/O is done. So the caller should not attempt to restore the
         * fs_si field after the write is done. The caller will convert the
         * error code back to its usual positive value when returning it.
         */
        if (ffs_fsfail_cleanup(ump, devfdp->error))
                devfdp->error = 0;
        if (devfdp->error != 0) {
                brelse(bp);
                return (-devfdp->error - 1);
        }
        if (MOUNTEDSOFTDEP(ump->um_mountp))
                softdep_setup_sbupdate(ump, fs, bp);
        if (devfdp->suspended)
                bp->b_flags |= B_VALIDSUSPWRT;
        if (devfdp->waitfor != MNT_WAIT)
                bawrite(bp);
        else if ((error = bwrite(bp)) != 0)
                devfdp->error = error;
        return (-devfdp->error - 1);
}

static int
ffs_extattrctl(struct mount *mp, int cmd, struct vnode *filename_vp,
        int attrnamespace, const char *attrname)
{

#ifdef UFS_EXTATTR
        return (ufs_extattrctl(mp, cmd, filename_vp, attrnamespace,
            attrname));
#else
        return (vfs_stdextattrctl(mp, cmd, filename_vp, attrnamespace,
            attrname));
#endif
}

static void
ffs_ifree(struct ufsmount *ump, struct inode *ip)
{

        if (ump->um_fstype == UFS1 && ip->i_din1 != NULL)
                uma_zfree(uma_ufs1, ip->i_din1);
        else if (ip->i_din2 != NULL)
                uma_zfree(uma_ufs2, ip->i_din2);
        uma_zfree_smr(uma_inode, ip);
}

static int dobkgrdwrite = 1;
SYSCTL_INT(_debug, OID_AUTO, dobkgrdwrite, CTLFLAG_RW, &dobkgrdwrite, 0,
    "Do background writes (honoring the BV_BKGRDWRITE flag)?");

/*
 * Complete a background write started from bwrite.
 */
static void
ffs_backgroundwritedone(struct buf *bp)
{
        struct bufobj *bufobj;
        struct buf *origbp;

#ifdef SOFTUPDATES
        if (!LIST_EMPTY(&bp->b_dep) && (bp->b_ioflags & BIO_ERROR) != 0)
                softdep_handle_error(bp);
#endif

        /*
         * Find the original buffer that we are writing.
         */
        bufobj = bp->b_bufobj;
        BO_LOCK(bufobj);
        if ((origbp = gbincore(bp->b_bufobj, bp->b_lblkno)) == NULL)
                panic("backgroundwritedone: lost buffer");

        /*
         * We should mark the cylinder group buffer origbp as
         * dirty, to not lose the failed write.
         */
        if ((bp->b_ioflags & BIO_ERROR) != 0)
                origbp->b_vflags |= BV_BKGRDERR;
        BO_UNLOCK(bufobj);
        /*
         * Process dependencies then return any unfinished ones.
         */
        if (!LIST_EMPTY(&bp->b_dep) && (bp->b_ioflags & BIO_ERROR) == 0)
                buf_complete(bp);
#ifdef SOFTUPDATES
        if (!LIST_EMPTY(&bp->b_dep))
                softdep_move_dependencies(bp, origbp);
#endif
        /*
         * This buffer is marked B_NOCACHE so when it is released
         * by biodone it will be tossed.  Clear B_IOSTARTED in case of error.
         */
        bp->b_flags |= B_NOCACHE;
        bp->b_flags &= ~(B_CACHE | B_IOSTARTED);
        pbrelvp(bp);

        /*
         * Prevent brelse() from trying to keep and re-dirtying bp on
         * errors. It causes b_bufobj dereference in
         * bdirty()/reassignbuf(), and b_bufobj was cleared in
         * pbrelvp() above.
         */
        if ((bp->b_ioflags & BIO_ERROR) != 0)
                bp->b_flags |= B_INVAL;
        bufdone(bp);
        BO_LOCK(bufobj);
        /*
         * Clear the BV_BKGRDINPROG flag in the original buffer
         * and awaken it if it is waiting for the write to complete.
         * If BV_BKGRDINPROG is not set in the original buffer it must
         * have been released and re-instantiated - which is not legal.
         */
        KASSERT((origbp->b_vflags & BV_BKGRDINPROG),
            ("backgroundwritedone: lost buffer2"));
        origbp->b_vflags &= ~BV_BKGRDINPROG;
        if (origbp->b_vflags & BV_BKGRDWAIT) {
                origbp->b_vflags &= ~BV_BKGRDWAIT;
                wakeup(&origbp->b_xflags);
        }
        BO_UNLOCK(bufobj);
}

/*
 * Write, release buffer on completion.  (Done by iodone
 * if async).  Do not bother writing anything if the buffer
 * is invalid.
 *
 * Note that we set B_CACHE here, indicating that buffer is
 * fully valid and thus cacheable.  This is true even of NFS
 * now so we set it generally.  This could be set either here
 * or in biodone() since the I/O is synchronous.  We put it
 * here.
 */
static int
ffs_bufwrite(struct buf *bp)
{
        struct buf *newbp;
        struct cg *cgp;

        CTR3(KTR_BUF, "bufwrite(%p) vp %p flags %X", bp, bp->b_vp, bp->b_flags);
        if (bp->b_flags & B_INVAL) {
                brelse(bp);
                return (0);
        }

        if (!BUF_ISLOCKED(bp))
                panic("bufwrite: buffer is not busy???");
        /*
         * If a background write is already in progress, delay
         * writing this block if it is asynchronous. Otherwise
         * wait for the background write to complete.
         */
        BO_LOCK(bp->b_bufobj);
        if (bp->b_vflags & BV_BKGRDINPROG) {
                if (bp->b_flags & B_ASYNC) {
                        BO_UNLOCK(bp->b_bufobj);
                        bdwrite(bp);
                        return (0);
                }
                bp->b_vflags |= BV_BKGRDWAIT;
                msleep(&bp->b_xflags, BO_LOCKPTR(bp->b_bufobj), PRIBIO,
                    "bwrbg", 0);
                if (bp->b_vflags & BV_BKGRDINPROG)
                        panic("bufwrite: still writing");
        }
        bp->b_vflags &= ~BV_BKGRDERR;
        BO_UNLOCK(bp->b_bufobj);

        /*
         * If this buffer is marked for background writing and we
         * do not have to wait for it, make a copy and write the
         * copy so as to leave this buffer ready for further use.
         *
         * This optimization eats a lot of memory.  If we have a page
         * or buffer shortfall we can't do it.
         */
        if (dobkgrdwrite && (bp->b_xflags & BX_BKGRDWRITE) &&
            (bp->b_flags & B_ASYNC) &&
            !vm_page_count_severe() &&
            !buf_dirty_count_severe()) {
                KASSERT(bp->b_iodone == NULL,
                    ("bufwrite: needs chained iodone (%p)", bp->b_iodone));

                /* get a new block */
                newbp = geteblk(bp->b_bufsize, GB_NOWAIT_BD);
                if (newbp == NULL)
                        goto normal_write;

                KASSERT(buf_mapped(bp), ("Unmapped cg"));
                memcpy(newbp->b_data, bp->b_data, bp->b_bufsize);
                BO_LOCK(bp->b_bufobj);
                bp->b_vflags |= BV_BKGRDINPROG;
                BO_UNLOCK(bp->b_bufobj);
                newbp->b_xflags |=
                    (bp->b_xflags & BX_FSPRIV) | BX_BKGRDMARKER;
                newbp->b_lblkno = bp->b_lblkno;
                newbp->b_blkno = bp->b_blkno;
                newbp->b_offset = bp->b_offset;
                newbp->b_iodone = ffs_backgroundwritedone;
                newbp->b_flags |= B_ASYNC;
                newbp->b_flags &= ~B_INVAL;
                pbgetvp(bp->b_vp, newbp);

#ifdef SOFTUPDATES
                /*
                 * Move over the dependencies.  If there are rollbacks,
                 * leave the parent buffer dirtied as it will need to
                 * be written again.
                 */
                if (LIST_EMPTY(&bp->b_dep) ||
                    softdep_move_dependencies(bp, newbp) == 0)
                        bundirty(bp);
#else
                bundirty(bp);
#endif

                /*
                 * Initiate write on the copy, release the original.  The
                 * BKGRDINPROG flag prevents it from going away until 
                 * the background write completes. We have to recalculate
                 * its check hash in case the buffer gets freed and then
                 * reconstituted from the buffer cache during a later read.
                 */
                if ((bp->b_xflags & BX_CYLGRP) != 0) {
                        cgp = (struct cg *)bp->b_data;
                        cgp->cg_ckhash = 0;
                        cgp->cg_ckhash =
                            calculate_crc32c(~0L, bp->b_data, bp->b_bcount);
                }
                bqrelse(bp);
                bp = newbp;
        } else
                /* Mark the buffer clean */
                bundirty(bp);

        /* Let the normal bufwrite do the rest for us */
normal_write:
        /*
         * If we are writing a cylinder group, update its time.
         */
        if ((bp->b_xflags & BX_CYLGRP) != 0) {
                cgp = (struct cg *)bp->b_data;
                cgp->cg_old_time = cgp->cg_time = time_second;
        }
        return (bufwrite(bp));
}

static void
ffs_geom_strategy(struct bufobj *bo, struct buf *bp)
{
        struct vnode *vp;
        struct buf *tbp;
        int error, nocopy;

        /*
         * This is the bufobj strategy for the private VCHR vnodes
         * used by FFS to access the underlying storage device.
         * We override the default bufobj strategy and thus bypass
         * VOP_STRATEGY() for these vnodes.
         */
        vp = bo2vnode(bo);
        KASSERT(bp->b_vp == NULL || bp->b_vp->v_type != VCHR ||
            bp->b_vp->v_rdev == NULL ||
            bp->b_vp->v_rdev->si_mountpt == NULL ||
            VFSTOUFS(bp->b_vp->v_rdev->si_mountpt) == NULL ||
            vp == VFSTOUFS(bp->b_vp->v_rdev->si_mountpt)->um_devvp,
            ("ffs_geom_strategy() with wrong vp"));
        if (bp->b_iocmd == BIO_WRITE) {
                if ((bp->b_flags & B_VALIDSUSPWRT) == 0 &&
                    bp->b_vp != NULL && bp->b_vp->v_mount != NULL &&
                    (bp->b_vp->v_mount->mnt_kern_flag & MNTK_SUSPENDED) != 0)
                        panic("ffs_geom_strategy: bad I/O");
                nocopy = bp->b_flags & B_NOCOPY;
                bp->b_flags &= ~(B_VALIDSUSPWRT | B_NOCOPY);
                if ((vp->v_vflag & VV_COPYONWRITE) && nocopy == 0 &&
                    vp->v_rdev->si_snapdata != NULL) {
                        if ((bp->b_flags & B_CLUSTER) != 0) {
                                runningbufwakeup(bp);
                                TAILQ_FOREACH(tbp, &bp->b_cluster.cluster_head,
                                              b_cluster.cluster_entry) {
                                        error = ffs_copyonwrite(vp, tbp);
                                        if (error != 0 &&
                                            error != EOPNOTSUPP) {
                                                bp->b_error = error;
                                                bp->b_ioflags |= BIO_ERROR;
                                                bp->b_flags &= ~B_BARRIER;
                                                bufdone(bp);
                                                return;
                                        }
                                }
                                (void)runningbufclaim(bp, bp->b_bufsize);
                        } else {
                                error = ffs_copyonwrite(vp, bp);
                                if (error != 0 && error != EOPNOTSUPP) {
                                        bp->b_error = error;
                                        bp->b_ioflags |= BIO_ERROR;
                                        bp->b_flags &= ~B_BARRIER;
                                        bufdone(bp);
                                        return;
                                }
                        }
                }
#ifdef SOFTUPDATES
                if ((bp->b_flags & B_CLUSTER) != 0) {
                        TAILQ_FOREACH(tbp, &bp->b_cluster.cluster_head,
                                      b_cluster.cluster_entry) {
                                if (!LIST_EMPTY(&tbp->b_dep))
                                        buf_start(tbp);
                        }
                } else {
                        if (!LIST_EMPTY(&bp->b_dep))
                                buf_start(bp);
                }

#endif
                /*
                 * Check for metadata that needs check-hashes and update them.
                 */
                switch (bp->b_xflags & BX_FSPRIV) {
                case BX_CYLGRP:
                        ((struct cg *)bp->b_data)->cg_ckhash = 0;
                        ((struct cg *)bp->b_data)->cg_ckhash =
                            calculate_crc32c(~0L, bp->b_data, bp->b_bcount);
                        break;

                case BX_SUPERBLOCK:
                case BX_INODE:
                case BX_INDIR:
                case BX_DIR:
                        printf("Check-hash write is unimplemented!!!\n");
                        break;

                case 0:
                        break;

                default:
                        printf("multiple buffer types 0x%b\n",
                            (bp->b_xflags & BX_FSPRIV), PRINT_UFS_BUF_XFLAGS);
                        break;
                }
        }
        if (bp->b_iocmd != BIO_READ && ffs_enxio_enable)
                bp->b_xflags |= BX_CVTENXIO;
        g_vfs_strategy(bo, bp);
}

int
ffs_own_mount(const struct mount *mp)
{

        if (mp->mnt_op == &ufs_vfsops)
                return (1);
        return (0);
}

#ifdef  DDB
#ifdef SOFTUPDATES

/* defined in ffs_softdep.c */
extern void db_print_ffs(struct ufsmount *ump);

DB_SHOW_COMMAND(ffs, db_show_ffs)
{
        struct mount *mp;
        struct ufsmount *ump;

        if (have_addr) {
                ump = VFSTOUFS((struct mount *)addr);
                db_print_ffs(ump);
                return;
        }

        TAILQ_FOREACH(mp, &mountlist, mnt_list) {
                if (!strcmp(mp->mnt_stat.f_fstypename, ufs_vfsconf.vfc_name))
                        db_print_ffs(VFSTOUFS(mp));
        }
}

#endif  /* SOFTUPDATES */
#endif  /* DDB */