/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 1988, 2010, Oracle and/or its affiliates. All rights reserved.
 * Copyright 2016 Joyent, Inc.
 * Copyright 2016 Toomas Soome <tsoome@me.com>
 * Copyright (c) 2016 by Delphix. All rights reserved.
 * Copyright 2017 RackTop Systems.
 * Copyright 2018 Nexenta Systems, Inc.
 */

/*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
/*        All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*
 * This file contains those functions from fs/vfs.c that can be
 * used with relatively little change.  Functions that differ
 * significantly from that are in other files.
 */

#include <sys/types.h>
#include <sys/t_lock.h>
#include <sys/param.h>
#include <sys/errno.h>
#include <sys/user.h>
#include <sys/fstyp.h>
#include <sys/kmem.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/mount.h>
#include <sys/vfs.h>
#include <sys/vfs_opreg.h>
#include <sys/fem.h>
#include <sys/mntent.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
#include <sys/statfs.h>
#include <sys/cred.h>
#include <sys/vnode.h>
#include <sys/rwstlock.h>
#include <sys/dnlc.h>
#include <sys/file.h>
#include <sys/time.h>
#include <sys/atomic.h>
#include <sys/cmn_err.h>
#include <sys/buf.h>
#include <sys/debug.h>
#include <sys/vnode.h>
#include <sys/ddi.h>
#include <sys/pathname.h>
#include <sys/poll.h>
#include <sys/sunddi.h>
#include <sys/sysmacros.h>
#include <sys/zone.h>
#include <sys/policy.h>
#include <sys/attr.h>
#include <fs/fs_subr.h>

#include <libfksmbfs.h>

static void vfs_clearmntopt_nolock(mntopts_t *, const char *, int);
static void vfs_setmntopt_nolock(mntopts_t *, const char *,
    const char *, int, int);
static int  vfs_optionisset_nolock(const mntopts_t *, const char *, char **);
// static void vfs_freemnttab(struct vfs *);
static void vfs_freeopt(mntopt_t *);
static void vfs_swapopttbl_nolock(mntopts_t *, mntopts_t *);
static void vfs_swapopttbl(mntopts_t *, mntopts_t *);
static void vfs_copyopttbl_extend(const mntopts_t *, mntopts_t *, int);
// static void vfs_createopttbl_extend(mntopts_t *, const char *,
//    const mntopts_t *);
// static char **vfs_copycancelopt_extend(char **const, int);
static void vfs_freecancelopt(char **);

/*
 * VFS global data.
 */
vnode_t *rootdir;               /* pointer to root inode vnode. */
struct vfs *rootvfs = NULL;     /* pointer to root vfs; head of VFS list. */
static krwlock_t vfslist;
struct vfs      *zone_vfslist;  /* list of FS's mounted in zone */

/* from os/vfs_conf.c */
const int nfstype = 5;
struct vfssw vfssw[10] = {
        { "BADVFS" },                           /* 0:invalid */
        { "" },                                 /* reserved for loadable fs */
        { "" },
        { "" },
        { "" },
};

/*
 * Table for generic options recognized in the VFS layer and acted
 * on at this level before parsing file system specific options.
 * The nosuid option is stronger than any of the devices and setuid
 * options, so those are canceled when nosuid is seen.
 *
 * All options which are added here need to be added to the
 * list of standard options in usr/src/cmd/fs.d/fslib.c as well.
 */
/*
 * VFS Mount options table
 */
static char *ro_cancel[] = { MNTOPT_RW, NULL };
static char *rw_cancel[] = { MNTOPT_RO, NULL };
static char *suid_cancel[] = { MNTOPT_NOSUID, NULL };
static char *nosuid_cancel[] = { MNTOPT_SUID, MNTOPT_DEVICES, MNTOPT_NODEVICES,
    MNTOPT_NOSETUID, MNTOPT_SETUID, NULL };
static char *devices_cancel[] = { MNTOPT_NODEVICES, NULL };
static char *nodevices_cancel[] = { MNTOPT_DEVICES, NULL };
static char *setuid_cancel[] = { MNTOPT_NOSETUID, NULL };
static char *nosetuid_cancel[] = { MNTOPT_SETUID, NULL };
static char *nbmand_cancel[] = { MNTOPT_NONBMAND, NULL };
static char *nonbmand_cancel[] = { MNTOPT_NBMAND, NULL };
static char *exec_cancel[] = { MNTOPT_NOEXEC, NULL };
static char *noexec_cancel[] = { MNTOPT_EXEC, NULL };

static const mntopt_t mntopts[] = {
/*
 *      option name             cancel options          default arg     flags
 */
        { MNTOPT_REMOUNT,       NULL,                   NULL,
                MO_NODISPLAY, (void *)0 },
        { MNTOPT_RO,            ro_cancel,              NULL,           0,
                (void *)0 },
        { MNTOPT_RW,            rw_cancel,              NULL,           0,
                (void *)0 },
        { MNTOPT_SUID,          suid_cancel,            NULL,           0,
                (void *)0 },
        { MNTOPT_NOSUID,        nosuid_cancel,          NULL,           0,
                (void *)0 },
        { MNTOPT_DEVICES,       devices_cancel,         NULL,           0,
                (void *)0 },
        { MNTOPT_NODEVICES,     nodevices_cancel,       NULL,           0,
                (void *)0 },
        { MNTOPT_SETUID,        setuid_cancel,          NULL,           0,
                (void *)0 },
        { MNTOPT_NOSETUID,      nosetuid_cancel,        NULL,           0,
                (void *)0 },
        { MNTOPT_NBMAND,        nbmand_cancel,          NULL,           0,
                (void *)0 },
        { MNTOPT_NONBMAND,      nonbmand_cancel,        NULL,           0,
                (void *)0 },
        { MNTOPT_EXEC,          exec_cancel,            NULL,           0,
                (void *)0 },
        { MNTOPT_NOEXEC,        noexec_cancel,          NULL,           0,
                (void *)0 },
};

const mntopts_t vfs_mntopts = {
        sizeof (mntopts) / sizeof (mntopt_t),
        (mntopt_t *)&mntopts[0]
};

/*
 * File system operation dispatch functions.
 */

int
fsop_mount(vfs_t *vfsp, vnode_t *mvp, struct mounta *uap, cred_t *cr)
{
        return (*(vfsp)->vfs_op->vfs_mount)(vfsp, mvp, uap, cr);
}

int
fsop_unmount(vfs_t *vfsp, int flag, cred_t *cr)
{
        return (*(vfsp)->vfs_op->vfs_unmount)(vfsp, flag, cr);
}

int
fsop_root(vfs_t *vfsp, vnode_t **vpp)
{
        return ((*(vfsp)->vfs_op->vfs_root)(vfsp, vpp));
}

int
fsop_statfs(vfs_t *vfsp, statvfs64_t *sp)
{
        return (*(vfsp)->vfs_op->vfs_statvfs)(vfsp, sp);
}

int
fsop_sync(vfs_t *vfsp, short flag, cred_t *cr)
{
        return (*(vfsp)->vfs_op->vfs_sync)(vfsp, flag, cr);
}

int
fsop_vget(vfs_t *vfsp, vnode_t **vpp, fid_t *fidp)
{
        return (*(vfsp)->vfs_op->vfs_vget)(vfsp, vpp, fidp);
}

int
fsop_mountroot(vfs_t *vfsp, enum whymountroot reason)
{
        return (*(vfsp)->vfs_op->vfs_mountroot)(vfsp, reason);
}

void
fsop_freefs(vfs_t *vfsp)
{
        (*(vfsp)->vfs_op->vfs_freevfs)(vfsp);
}

int
fsop_vnstate(vfs_t *vfsp, vnode_t *vp, vntrans_t nstate)
{
        return ((*(vfsp)->vfs_op->vfs_vnstate)(vfsp, vp, nstate));
}

int
fsop_sync_by_kind(int fstype, short flag, cred_t *cr)
{
        ASSERT((fstype >= 0) && (fstype < nfstype));

        if (ALLOCATED_VFSSW(&vfssw[fstype]) && VFS_INSTALLED(&vfssw[fstype]))
                return (*vfssw[fstype].vsw_vfsops.vfs_sync) (NULL, flag, cr);
        else
                return (ENOTSUP);
}

/*
 * File system initialization.  vfs_setfsops() must be called from a file
 * system's init routine.
 */

static int
fs_copyfsops(const fs_operation_def_t *template, vfsops_t *actual,
    int *unused_ops)
{
        static const fs_operation_trans_def_t vfs_ops_table[] = {
                VFSNAME_MOUNT, offsetof(vfsops_t, vfs_mount),
                        fs_nosys, fs_nosys,

                VFSNAME_UNMOUNT, offsetof(vfsops_t, vfs_unmount),
                        fs_nosys, fs_nosys,

                VFSNAME_ROOT, offsetof(vfsops_t, vfs_root),
                        fs_nosys, fs_nosys,

                VFSNAME_STATVFS, offsetof(vfsops_t, vfs_statvfs),
                        fs_nosys, fs_nosys,

                VFSNAME_SYNC, offsetof(vfsops_t, vfs_sync),
                        (fs_generic_func_p) fs_sync,
                        (fs_generic_func_p) fs_sync,    /* No errors allowed */

                VFSNAME_VGET, offsetof(vfsops_t, vfs_vget),
                        fs_nosys, fs_nosys,

                VFSNAME_MOUNTROOT, offsetof(vfsops_t, vfs_mountroot),
                        fs_nosys, fs_nosys,

                VFSNAME_FREEVFS, offsetof(vfsops_t, vfs_freevfs),
                        (fs_generic_func_p)(uintptr_t)fs_freevfs,
                        (fs_generic_func_p)(uintptr_t)
                        fs_freevfs,     /* Shouldn't fail */

                VFSNAME_VNSTATE, offsetof(vfsops_t, vfs_vnstate),
                        (fs_generic_func_p)fs_nosys,
                        (fs_generic_func_p)fs_nosys,

                NULL, 0, NULL, NULL
        };

        return (fs_build_vector(actual, unused_ops, vfs_ops_table, template));
}

/* zfs_boot_init() */

int
vfs_setfsops(int fstype, const fs_operation_def_t *template, vfsops_t **actual)
{
        int error;
        int unused_ops;

        /*
         * Verify that fstype refers to a valid fs.  Note that
         * 0 is valid since it's used to set "stray" ops.
         */
        if ((fstype < 0) || (fstype >= nfstype))
                return (EINVAL);

        if (!ALLOCATED_VFSSW(&vfssw[fstype]))
                return (EINVAL);

        /* Set up the operations vector. */

        error = fs_copyfsops(template, &vfssw[fstype].vsw_vfsops, &unused_ops);

        if (error != 0)
                return (error);

        vfssw[fstype].vsw_flag |= VSW_INSTALLED;

        if (actual != NULL)
                *actual = &vfssw[fstype].vsw_vfsops;

#if DEBUG
        if (unused_ops != 0)
                cmn_err(CE_WARN, "vfs_setfsops: %s: %d operations supplied "
                    "but not used", vfssw[fstype].vsw_name, unused_ops);
#endif

        return (0);
}

int
vfs_makefsops(const fs_operation_def_t *template, vfsops_t **actual)
{
        int error;
        int unused_ops;

        *actual = (vfsops_t *)kmem_alloc(sizeof (vfsops_t), KM_SLEEP);

        error = fs_copyfsops(template, *actual, &unused_ops);
        if (error != 0) {
                kmem_free(*actual, sizeof (vfsops_t));
                *actual = NULL;
                return (error);
        }

        return (0);
}

/*
 * Free a vfsops structure created as a result of vfs_makefsops().
 * NOTE: For a vfsops structure initialized by vfs_setfsops(), use
 * vfs_freevfsops_by_type().
 */
void
vfs_freevfsops(vfsops_t *vfsops)
{
        kmem_free(vfsops, sizeof (vfsops_t));
}

/*
 * Since the vfsops structure is part of the vfssw table and wasn't
 * really allocated, we're not really freeing anything.  We keep
 * the name for consistency with vfs_freevfsops().  We do, however,
 * need to take care of a little bookkeeping.
 * NOTE: For a vfsops structure created by vfs_setfsops(), use
 * vfs_freevfsops_by_type().
 */
int
vfs_freevfsops_by_type(int fstype)
{

        /* Verify that fstype refers to a loaded fs (and not fsid 0). */
        if ((fstype <= 0) || (fstype >= nfstype))
                return (EINVAL);

        WLOCK_VFSSW();
        if ((vfssw[fstype].vsw_flag & VSW_INSTALLED) == 0) {
                WUNLOCK_VFSSW();
                return (EINVAL);
        }

        vfssw[fstype].vsw_flag &= ~VSW_INSTALLED;
        WUNLOCK_VFSSW();

        return (0);
}

/* Support routines used to reference vfs_op */

/* Set the operations vector for a vfs */
void
vfs_setops(vfs_t *vfsp, vfsops_t *vfsops)
{

        ASSERT(vfsp != NULL);
        ASSERT(vfsops != NULL);

        vfsp->vfs_op = vfsops;
}

/* Retrieve the operations vector for a vfs */
vfsops_t *
vfs_getops(vfs_t *vfsp)
{

        ASSERT(vfsp != NULL);

        return (vfsp->vfs_op);
}

/*
 * Returns non-zero (1) if the vfsops matches that of the vfs.
 * Returns zero (0) if not.
 */
int
vfs_matchops(vfs_t *vfsp, vfsops_t *vfsops)
{
        return (vfs_getops(vfsp) == vfsops);
}

/*
 * Returns non-zero (1) if the file system has installed a non-default,
 * non-error vfs_sync routine.  Returns zero (0) otherwise.
 */
int
vfs_can_sync(vfs_t *vfsp)
{
        /* vfs_sync() routine is not the default/error function */
        return (vfs_getops(vfsp)->vfs_sync != fs_sync);
}

/*
 * Initialize a vfs structure.
 */
void
vfs_init(vfs_t *vfsp, vfsops_t *op, void *data)
{
        /* Always do full init, like vfs_alloc() */
        bzero(vfsp, sizeof (vfs_t));
        vfsp->vfs_count = 0;
        vfsp->vfs_next = vfsp;
        vfsp->vfs_prev = vfsp;
        vfsp->vfs_zone_next = vfsp;
        vfsp->vfs_zone_prev = vfsp;
        vfsp->vfs_lofi_id = 0;
        sema_init(&vfsp->vfs_reflock, 1, NULL, SEMA_DEFAULT, NULL);
        vfsimpl_setup(vfsp);
        vfsp->vfs_data = (data);
        vfs_setops((vfsp), (op));
}

/*
 * Allocate and initialize the vfs implementation private data
 * structure, vfs_impl_t.
 */
void
vfsimpl_setup(vfs_t *vfsp)
{
        int i;

        if (vfsp->vfs_implp != NULL) {
                return;
        }

        vfsp->vfs_implp = kmem_alloc(sizeof (vfs_impl_t), KM_SLEEP);
        /* Note that these are #define'd in vfs.h */
        vfsp->vfs_vskap = NULL;
        vfsp->vfs_fstypevsp = NULL;

        /* Set size of counted array, then zero the array */
        vfsp->vfs_featureset[0] = VFS_FEATURE_MAXSZ - 1;
        for (i = 1; i <  VFS_FEATURE_MAXSZ; i++) {
                vfsp->vfs_featureset[i] = 0;
        }
}

/*
 * Release the vfs_impl_t structure, if it exists. Some unbundled
 * filesystems may not use the newer version of vfs and thus
 * would not contain this implementation private data structure.
 */
void
vfsimpl_teardown(vfs_t *vfsp)
{
        vfs_impl_t      *vip = vfsp->vfs_implp;

        if (vip == NULL)
                return;

        kmem_free(vfsp->vfs_implp, sizeof (vfs_impl_t));
        vfsp->vfs_implp = NULL;
}

/*
 * VFS system calls: mount, umount, syssync, statfs, fstatfs, statvfs,
 * fstatvfs, and sysfs moved to common/syscall.
 */

// vfs_sync, sync

/*
 * External routines.
 */

krwlock_t vfssw_lock;   /* lock accesses to vfssw */

/*
 * Lock for accessing the vfs linked list.  Initialized in vfs_mountroot(),
 * but otherwise should be accessed only via vfs_list_lock() and
 * vfs_list_unlock().  Also used to protect the timestamp for mods to the list.
 */
static krwlock_t vfslist;

// vfs_mountdevices(void)
// vfs_mountdev1(void)
// vfs_mountfs()
// vfs_mountroot()
// lofi_add, lofi_remove


/*
 * Mount the FS for the test jig.  Based on domount()
 */
int
fake_domount(char *fsname, struct mounta *uap, struct vfs **vfspp)
{
        vnode_t         *vp;
        struct cred     *credp;
        struct vfssw    *vswp;
        vfsops_t        *vfsops;
        struct vfs      *vfsp = NULL;
        mntopts_t       mnt_mntopts;
        int             error = 0;
        int             copyout_error = 0;
        char            *opts = uap->optptr;
        char            *inargs = opts;
        int             optlen = uap->optlen;

        credp = CRED();

        /*
         * Test jig specific: mount on rootdir
         */
        if (rootvfs != NULL)
                return (EBUSY);
        vp = rootdir;

        /*
         * The v_flag value for the mount point vp is permanently set
         * to VVFSLOCK so that no one bypasses the vn_vfs*locks routine
         * for mount point locking.
         */
        mutex_enter(&vp->v_lock);
        vp->v_flag |= VVFSLOCK;
        mutex_exit(&vp->v_lock);

        mnt_mntopts.mo_count = 0;

        /*
         * Find the ops vector to use to invoke the file system-specific mount
         * method.  If the fsname argument is non-NULL, use it directly.
         */
        if ((vswp = vfs_getvfssw(fsname)) == NULL) {
                return (EINVAL);
        }
        if (!VFS_INSTALLED(vswp))
                return (EINVAL);

        // secpolicy_fs_allowed_mount(fsname)

        vfsops = &vswp->vsw_vfsops;

        vfs_copyopttbl(&vswp->vsw_optproto, &mnt_mntopts);

        /*
         * Fetch mount options and parse them for generic vfs options
         */
        if (uap->flags & MS_OPTIONSTR) {
                /*
                 * Limit the buffer size
                 */
                if (optlen < 0 || optlen > MAX_MNTOPT_STR) {
                        error = EINVAL;
                        goto errout;
                }
                if ((uap->flags & MS_SYSSPACE) == 0) {
                        inargs = kmem_alloc(MAX_MNTOPT_STR, KM_SLEEP);
                        inargs[0] = '\0';
                        if (optlen) {
                                error = copyinstr(opts, inargs, (size_t)optlen,
                                    NULL);
                                if (error) {
                                        goto errout;
                                }
                        }
                }
                vfs_parsemntopts(&mnt_mntopts, inargs, 0);
        }
        /*
         * Flag bits override the options string.
         */
        if (uap->flags & MS_REMOUNT)
                vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_REMOUNT, NULL, 0, 0);
        if (uap->flags & MS_RDONLY)
                vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_RO, NULL, 0, 0);
        if (uap->flags & MS_NOSUID)
                vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL, 0, 0);

        /*
         * Check if this is a remount; must be set in the option string and
         * the file system must support a remount option.
         */
        if (vfs_optionisset_nolock(&mnt_mntopts,
            MNTOPT_REMOUNT, NULL)) {
                /* disallow here */
                error = ENOTSUP;
                goto errout;
        }

        /*
         * uap->flags and vfs_optionisset() should agree.
         */
        if (vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_RO, NULL)) {
                uap->flags |= MS_RDONLY;
        }
        if (vfs_optionisset_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL)) {
                uap->flags |= MS_NOSUID;
        }
        // nbmand ...

        /*
         * If we are splicing the fs into the namespace,
         * perform mount point checks...
         * (always splice=0 here)
         */

        if ((uap->flags & (MS_DATA | MS_OPTIONSTR)) == 0) {
                uap->dataptr = NULL;
                uap->datalen = 0;
        }

        /*
         * If this is a remount, ... (never here)
         */
        vfsp = vfs_alloc(KM_SLEEP);
        VFS_INIT(vfsp, vfsops, NULL);

        VFS_HOLD(vfsp);

        // lofi_add(fsname, vfsp, &mnt_mntopts, uap)

        /*
         * PRIV_SYS_MOUNT doesn't mean you can become root.
         */
        uap->flags |= MS_NOSUID;
        vfs_setmntopt_nolock(&mnt_mntopts, MNTOPT_NOSUID, NULL, 0, 0);

        /*
         * The vfs_reflock...
         */

        /*
         * Lock the vfs...
         */
        if ((error = vfs_lock(vfsp)) != 0) {
                vfs_free(vfsp);
                vfsp = NULL;
                goto errout;
        }

        /*
         * Add device to mount in progress table...
         */
        /*
         * Invalidate cached entry for the mount point.
         */

        /*
         * If have an option string but the filesystem doesn't supply a
         * prototype options table, create a table...
         */

        /*
         * Serialize with zone state transitions...
         */

        // mount_in_progress(zone);

        /*
         * Instantiate (or reinstantiate) the file system...
         */
        vfs_swapopttbl(&mnt_mntopts, &vfsp->vfs_mntopts);

        vfs_setresource(vfsp, uap->spec, 0);
        vfs_setmntpoint(vfsp, uap->dir, 0);

        /*
         * going to mount on this vnode, so notify.
         */
        // vnevent_mountedover(vp, NULL);
        error = VFS_MOUNT(vfsp, vp, uap, credp);

        if (uap->flags & MS_RDONLY)
                vfs_setmntopt(vfsp, MNTOPT_RO, NULL, 0);
        if (uap->flags & MS_NOSUID)
                vfs_setmntopt(vfsp, MNTOPT_NOSUID, NULL, 0);
        if (uap->flags & MS_GLOBAL)
                vfs_setmntopt(vfsp, MNTOPT_GLOBAL, NULL, 0);

        if (error) {
                // lofi_remove(vfsp);

                // (remount == 0)
                vfs_unlock(vfsp);
                // vfs_freemnttab(vfsp);
                vfs_free(vfsp);
                vfsp = NULL;
        } else {
                /*
                 * Set the mount time to now
                 */
                // vfsp->vfs_mtime = ddi_get_time();
                // if (remount) ...
                // else if (splice) vfs_add(vp, vfsp, flags)
                // else VFS_HOLD(vfsp);

                /*
                 * Test jig specific:
                 * Do sort of like vfs_add for vp=rootdir
                 * Already have hold on vp.
                 */
                vfsp->vfs_vnodecovered = vp;
                vfsp->vfs_flag |= (VFS_NOSETUID|VFS_NODEVICES);
                VFS_HOLD(vfsp);
                rootvfs = vfsp;

                /*
                 * Set flags for global options encountered
                 */
                if (vfs_optionisset(vfsp, MNTOPT_RO, NULL))
                        vfsp->vfs_flag |= VFS_RDONLY;
                else
                        vfsp->vfs_flag &= ~VFS_RDONLY;
                if (vfs_optionisset(vfsp, MNTOPT_NOSUID, NULL)) {
                        vfsp->vfs_flag |= (VFS_NOSETUID|VFS_NODEVICES);
                } else {
                        if (vfs_optionisset(vfsp, MNTOPT_NODEVICES, NULL))
                                vfsp->vfs_flag |= VFS_NODEVICES;
                        else
                                vfsp->vfs_flag &= ~VFS_NODEVICES;
                        if (vfs_optionisset(vfsp, MNTOPT_NOSETUID, NULL))
                                vfsp->vfs_flag |= VFS_NOSETUID;
                        else
                                vfsp->vfs_flag &= ~VFS_NOSETUID;
                }
                if (vfs_optionisset(vfsp, MNTOPT_NBMAND, NULL))
                        vfsp->vfs_flag |= VFS_NBMAND;
                else
                        vfsp->vfs_flag &= ~VFS_NBMAND;

                if (vfs_optionisset(vfsp, MNTOPT_XATTR, NULL))
                        vfsp->vfs_flag |= VFS_XATTR;
                else
                        vfsp->vfs_flag &= ~VFS_XATTR;

                if (vfs_optionisset(vfsp, MNTOPT_NOEXEC, NULL))
                        vfsp->vfs_flag |= VFS_NOEXEC;
                else
                        vfsp->vfs_flag &= ~VFS_NOEXEC;

                /*
                 * Now construct the output option string of options
                 * we recognized.
                 */
                if (uap->flags & MS_OPTIONSTR) {
                        vfs_list_read_lock();
                        copyout_error = vfs_buildoptionstr(
                            &vfsp->vfs_mntopts, inargs, optlen);
                        vfs_list_unlock();
                        if (copyout_error == 0 &&
                            (uap->flags & MS_SYSSPACE) == 0) {
                                copyout_error = copyout(inargs, opts, optlen);
                        }
                }

                /*
                 * If this isn't a remount, set up the vopstats...
                 */
                if (vswp->vsw_flag & VSW_XID)
                        vfsp->vfs_flag |= VFS_XID;

                vfs_unlock(vfsp);

                /*
                 * Test jig specicific:
                 * Replace rootdir with the mounted root.
                 */
                error = VFS_ROOT(vfsp, &rootdir);
                if (error != 0) {
                        panic("fake_domount, get root %d\n", error);
                }
        }
        // mount_completed(zone);
        // zone_rele(zone);

        // if (splice)
        //      vn_vfsunlock(vp);

        if ((error == 0) && (copyout_error == 0)) {
                /* get_vskstat_anchor() */
                /* Return vfsp to caller. */
                *vfspp = vfsp;
        }
errout:
        vfs_freeopttbl(&mnt_mntopts);
        /* resource, mountpt not allocated */
        /* no addmip, delmip */
        ASSERT(vswp != NULL);
        vfs_unrefvfssw(vswp);
        if (inargs != opts)
                kmem_free(inargs, MAX_MNTOPT_STR);
        if (copyout_error) {
                if (vfsp != NULL) {
                        // lofi_remove(vfsp);
                        VFS_RELE(vfsp);
                }
                error = copyout_error;
        }
        return (error);
}


static void
vfs_setpath(
    struct vfs *vfsp,           /* vfs being updated */
    refstr_t **refp,            /* Ref-count string to contain the new path */
    const char *newpath,        /* Path to add to refp (above) */
    uint32_t flag)              /* flag */
{
        // size_t len;
        refstr_t *ref;
        // char *sp;
        int have_list_lock = 0;

        ASSERT(!VFS_ON_LIST(vfsp) || vfs_lock_held(vfsp));

        /*
         * New path must be less than MAXPATHLEN because mntfs
         * will only display up to MAXPATHLEN bytes. This is currently
         * safe, because domount() uses pn_get(), and other callers
         * similarly cap the size to fewer than MAXPATHLEN bytes.
         */

        ASSERT(strlen(newpath) < MAXPATHLEN);

        /* mntfs requires consistency while vfs list lock is held */

        if (VFS_ON_LIST(vfsp)) {
                have_list_lock = 1;
                vfs_list_lock();
        }

        if (*refp != NULL)
                refstr_rele(*refp);

        /*
         * If we are in a non-global zone... (do something else)
         */
        ref = refstr_alloc(newpath);
        *refp = ref;

        if (have_list_lock) {
                vfs_mnttab_modtimeupd();
                vfs_list_unlock();
        }
}

/*
 * Record a mounted resource name in a vfs structure.
 * If vfsp is already mounted, caller must hold the vfs lock.
 */
void
vfs_setresource(struct vfs *vfsp, const char *resource, uint32_t flag)
{
        if (resource == NULL || resource[0] == '\0')
                resource = VFS_NORESOURCE;
        vfs_setpath(vfsp, &vfsp->vfs_resource, resource, flag);
}

/*
 * Record a mount point name in a vfs structure.
 * If vfsp is already mounted, caller must hold the vfs lock.
 */
void
vfs_setmntpoint(struct vfs *vfsp, const char *mntpt, uint32_t flag)
{
        if (mntpt == NULL || mntpt[0] == '\0')
                mntpt = VFS_NOMNTPT;
        vfs_setpath(vfsp, &vfsp->vfs_mntpt, mntpt, flag);
}

/* Returns the vfs_resource. Caller must call refstr_rele() when finished. */

refstr_t *
vfs_getresource(const struct vfs *vfsp)
{
        refstr_t *resource;

        vfs_list_read_lock();
        resource = vfsp->vfs_resource;
        refstr_hold(resource);
        vfs_list_unlock();

        return (resource);
}

/* Returns the vfs_mntpt. Caller must call refstr_rele() when finished. */

refstr_t *
vfs_getmntpoint(const struct vfs *vfsp)
{
        refstr_t *mntpt;

        vfs_list_read_lock();
        mntpt = vfsp->vfs_mntpt;
        refstr_hold(mntpt);
        vfs_list_unlock();

        return (mntpt);
}

// vfs_createopttbl_extend
// vfs_createopttbl

/*
 * Swap two mount options tables
 */
static void
vfs_swapopttbl_nolock(mntopts_t *optbl1, mntopts_t *optbl2)
{
        uint_t tmpcnt;
        mntopt_t *tmplist;

        tmpcnt = optbl2->mo_count;
        tmplist = optbl2->mo_list;
        optbl2->mo_count = optbl1->mo_count;
        optbl2->mo_list = optbl1->mo_list;
        optbl1->mo_count = tmpcnt;
        optbl1->mo_list = tmplist;
}

static void
vfs_swapopttbl(mntopts_t *optbl1, mntopts_t *optbl2)
{
        vfs_list_lock();
        vfs_swapopttbl_nolock(optbl1, optbl2);
        vfs_mnttab_modtimeupd();
        vfs_list_unlock();
}

static char **
vfs_copycancelopt_extend(char **const moc, int extend)
{
        int i = 0;
        int j;
        char **result;

        if (moc != NULL) {
                for (; moc[i] != NULL; i++)
                        /* count number of options to cancel */;
        }

        if (i + extend == 0)
                return (NULL);

        result = kmem_alloc((i + extend + 1) * sizeof (char *), KM_SLEEP);

        for (j = 0; j < i; j++) {
                result[j] = kmem_alloc(strlen(moc[j]) + 1, KM_SLEEP);
                (void) strcpy(result[j], moc[j]);
        }
        for (; j <= i + extend; j++)
                result[j] = NULL;

        return (result);
}

static void
vfs_copyopt(const mntopt_t *s, mntopt_t *d)
{
        char *sp, *dp;

        d->mo_flags = s->mo_flags;
        d->mo_data = s->mo_data;
        sp = s->mo_name;
        if (sp != NULL) {
                dp = kmem_alloc(strlen(sp) + 1, KM_SLEEP);
                (void) strcpy(dp, sp);
                d->mo_name = dp;
        } else {
                d->mo_name = NULL; /* should never happen */
        }

        d->mo_cancel = vfs_copycancelopt_extend(s->mo_cancel, 0);

        sp = s->mo_arg;
        if (sp != NULL) {
                dp = kmem_alloc(strlen(sp) + 1, KM_SLEEP);
                (void) strcpy(dp, sp);
                d->mo_arg = dp;
        } else {
                d->mo_arg = NULL;
        }
}

// vfs_copyopttbl_extend
// vfs_copyopttbl

/*
 * Copy a mount options table, possibly allocating some spare
 * slots at the end.  It is permissible to copy_extend the NULL table.
 */
static void
vfs_copyopttbl_extend(const mntopts_t *smo, mntopts_t *dmo, int extra)
{
        uint_t i, count;
        mntopt_t *motbl;

        /*
         * Clear out any existing stuff in the options table being initialized
         */
        vfs_freeopttbl(dmo);
        count = (smo == NULL) ? 0 : smo->mo_count;
        if ((count + extra) == 0)       /* nothing to do */
                return;
        dmo->mo_count = count + extra;
        motbl = kmem_zalloc((count + extra) * sizeof (mntopt_t), KM_SLEEP);
        dmo->mo_list = motbl;
        for (i = 0; i < count; i++) {
                vfs_copyopt(&smo->mo_list[i], &motbl[i]);
        }
        for (i = count; i < count + extra; i++) {
                motbl[i].mo_flags = MO_EMPTY;
        }
}

/*
 * Copy a mount options table.
 *
 * This function is *not* for general use by filesystems.
 *
 * Note: caller is responsible for locking the vfs list, if needed,
 *       to protect smo and dmo.
 */
void
vfs_copyopttbl(const mntopts_t *smo, mntopts_t *dmo)
{
        vfs_copyopttbl_extend(smo, dmo, 0);
}

static char **
vfs_mergecancelopts(const mntopt_t *mop1, const mntopt_t *mop2)
{
        int c1 = 0;
        int c2 = 0;
        char **result;
        char **sp1, **sp2, **dp;

        /*
         * First we count both lists of cancel options.
         * If either is NULL or has no elements, we return a copy of
         * the other.
         */
        if (mop1->mo_cancel != NULL) {
                for (; mop1->mo_cancel[c1] != NULL; c1++)
                        /* count cancel options in mop1 */;
        }

        if (c1 == 0)
                return (vfs_copycancelopt_extend(mop2->mo_cancel, 0));

        if (mop2->mo_cancel != NULL) {
                for (; mop2->mo_cancel[c2] != NULL; c2++)
                        /* count cancel options in mop2 */;
        }

        result = vfs_copycancelopt_extend(mop1->mo_cancel, c2);

        if (c2 == 0)
                return (result);

        /*
         * When we get here, we've got two sets of cancel options;
         * we need to merge the two sets.  We know that the result
         * array has "c1+c2+1" entries and in the end we might shrink
         * it.
         * Result now has a copy of the c1 entries from mop1; we'll
         * now lookup all the entries of mop2 in mop1 and copy it if
         * it is unique.
         * This operation is O(n^2) but it's only called once per
         * filesystem per duplicate option.  This is a situation
         * which doesn't arise with the filesystems in ON and
         * n is generally 1.
         */

        dp = &result[c1];
        for (sp2 = mop2->mo_cancel; *sp2 != NULL; sp2++) {
                for (sp1 = mop1->mo_cancel; *sp1 != NULL; sp1++) {
                        if (strcmp(*sp1, *sp2) == 0)
                                break;
                }
                if (*sp1 == NULL) {
                        /*
                         * Option *sp2 not found in mop1, so copy it.
                         * The calls to vfs_copycancelopt_extend()
                         * guarantee that there's enough room.
                         */
                        *dp = kmem_alloc(strlen(*sp2) + 1, KM_SLEEP);
                        (void) strcpy(*dp++, *sp2);
                }
        }
        if (dp != &result[c1+c2]) {
                size_t bytes = (dp - result + 1) * sizeof (char *);
                char **nres = kmem_alloc(bytes, KM_SLEEP);

                bcopy(result, nres, bytes);
                kmem_free(result, (c1 + c2 + 1) * sizeof (char *));
                result = nres;
        }
        return (result);
}

/*
 * Merge two mount option tables (outer and inner) into one.  This is very
 * similar to "merging" global variables and automatic variables in C.
 *
 * This isn't (and doesn't have to be) fast.
 *
 * This function is *not* for general use by filesystems.
 *
 * Note: caller is responsible for locking the vfs list, if needed,
 *       to protect omo, imo & dmo.
 */
void
vfs_mergeopttbl(const mntopts_t *omo, const mntopts_t *imo, mntopts_t *dmo)
{
        uint_t i, count;
        mntopt_t *mop, *motbl;
        uint_t freeidx;

        /*
         * First determine how much space we need to allocate.
         */
        count = omo->mo_count;
        for (i = 0; i < imo->mo_count; i++) {
                if (imo->mo_list[i].mo_flags & MO_EMPTY)
                        continue;
                if (vfs_hasopt(omo, imo->mo_list[i].mo_name) == NULL)
                        count++;
        }
        ASSERT(count >= omo->mo_count &&
            count <= omo->mo_count + imo->mo_count);
        motbl = kmem_alloc(count * sizeof (mntopt_t), KM_SLEEP);
        for (i = 0; i < omo->mo_count; i++)
                vfs_copyopt(&omo->mo_list[i], &motbl[i]);
        freeidx = omo->mo_count;
        for (i = 0; i < imo->mo_count; i++) {
                if (imo->mo_list[i].mo_flags & MO_EMPTY)
                        continue;
                if ((mop = vfs_hasopt(omo, imo->mo_list[i].mo_name)) != NULL) {
                        char **newcanp;
                        uint_t index = mop - omo->mo_list;

                        newcanp = vfs_mergecancelopts(mop, &motbl[index]);

                        vfs_freeopt(&motbl[index]);
                        vfs_copyopt(&imo->mo_list[i], &motbl[index]);

                        vfs_freecancelopt(motbl[index].mo_cancel);
                        motbl[index].mo_cancel = newcanp;
                } else {
                        /*
                         * If it's a new option, just copy it over to the first
                         * free location.
                         */
                        vfs_copyopt(&imo->mo_list[i], &motbl[freeidx++]);
                }
        }
        dmo->mo_count = count;
        dmo->mo_list = motbl;
}

/*
 * Functions to set and clear mount options in a mount options table.
 */

/*
 * Clear a mount option, if it exists.
 *
 * The update_mnttab arg indicates whether mops is part of a vfs that is on
 * the vfs list.
 */
static void
vfs_clearmntopt_nolock(mntopts_t *mops, const char *opt, int update_mnttab)
{
        struct mntopt *mop;
        uint_t i, count;

        ASSERT(!update_mnttab || RW_WRITE_HELD(&vfslist));

        count = mops->mo_count;
        for (i = 0; i < count; i++) {
                mop = &mops->mo_list[i];

                if (mop->mo_flags & MO_EMPTY)
                        continue;
                if (strcmp(opt, mop->mo_name))
                        continue;
                mop->mo_flags &= ~MO_SET;
                if (mop->mo_arg != NULL) {
                        kmem_free(mop->mo_arg, strlen(mop->mo_arg) + 1);
                }
                mop->mo_arg = NULL;
                if (update_mnttab)
                        vfs_mnttab_modtimeupd();
                break;
        }
}

void
vfs_clearmntopt(struct vfs *vfsp, const char *opt)
{
        int gotlock = 0;

        if (VFS_ON_LIST(vfsp)) {
                gotlock = 1;
                vfs_list_lock();
        }
        vfs_clearmntopt_nolock(&vfsp->vfs_mntopts, opt, gotlock);
        if (gotlock)
                vfs_list_unlock();
}


/*
 * Set a mount option on...
 */
static void
vfs_setmntopt_nolock(mntopts_t *mops, const char *opt,
    const char *arg, int flags, int update_mnttab)
{
        mntopt_t *mop;
        uint_t i, count;
        char *sp;

        ASSERT(!update_mnttab || RW_WRITE_HELD(&vfslist));

        if (flags & VFS_CREATEOPT) {
                if (vfs_hasopt(mops, opt) != NULL) {
                        flags &= ~VFS_CREATEOPT;
                }
        }
        count = mops->mo_count;
        for (i = 0; i < count; i++) {
                mop = &mops->mo_list[i];

                if (mop->mo_flags & MO_EMPTY) {
                        if ((flags & VFS_CREATEOPT) == 0)
                                continue;
                        sp = kmem_alloc(strlen(opt) + 1, KM_SLEEP);
                        (void) strcpy(sp, opt);
                        mop->mo_name = sp;
                        if (arg != NULL)
                                mop->mo_flags = MO_HASVALUE;
                        else
                                mop->mo_flags = 0;
                } else if (strcmp(opt, mop->mo_name)) {
                        continue;
                }
                if ((mop->mo_flags & MO_IGNORE) && (flags & VFS_NOFORCEOPT))
                        break;
                if (arg != NULL && (mop->mo_flags & MO_HASVALUE) != 0) {
                        sp = kmem_alloc(strlen(arg) + 1, KM_SLEEP);
                        (void) strcpy(sp, arg);
                } else {
                        sp = NULL;
                }
                if (mop->mo_arg != NULL)
                        kmem_free(mop->mo_arg, strlen(mop->mo_arg) + 1);
                mop->mo_arg = sp;
                if (flags & VFS_DISPLAY)
                        mop->mo_flags &= ~MO_NODISPLAY;
                if (flags & VFS_NODISPLAY)
                        mop->mo_flags |= MO_NODISPLAY;
                mop->mo_flags |= MO_SET;
                if (mop->mo_cancel != NULL) {
                        char **cp;

                        for (cp = mop->mo_cancel; *cp != NULL; cp++)
                                vfs_clearmntopt_nolock(mops, *cp, 0);
                }
                if (update_mnttab)
                        vfs_mnttab_modtimeupd();
                break;
        }
}

void
vfs_setmntopt(struct vfs *vfsp, const char *opt, const char *arg, int flags)
{
        int gotlock = 0;

        if (VFS_ON_LIST(vfsp)) {
                gotlock = 1;
                vfs_list_lock();
        }
        vfs_setmntopt_nolock(&vfsp->vfs_mntopts, opt, arg, flags, gotlock);
        if (gotlock)
                vfs_list_unlock();
}

// vfs_addtag
// vfs_settag
// vfs_clrtag

/*
 * Function to parse an option string and fill in a mount options table.
 * Unknown options are silently ignored.  The input option string is modified
 * by replacing separators with nulls.  If the create flag is set, options
 * not found in the table are just added on the fly.  The table must have
 * an option slot marked MO_EMPTY to add an option on the fly.
 *
 * This function is *not* for general use by filesystems.
 *
 * Note: caller is responsible for locking the vfs list, if needed,
 *       to protect mops..
 */
void
vfs_parsemntopts(mntopts_t *mops, char *osp, int create)
{
        char *s = osp, *p, *nextop, *valp, *cp, *ep = NULL;
        int setflg = VFS_NOFORCEOPT;

        if (osp == NULL)
                return;
        while (*s != '\0') {
                p = strchr(s, ',');     /* find next option */
                if (p == NULL) {
                        cp = NULL;
                        p = s + strlen(s);
                } else {
                        cp = p;         /* save location of comma */
                        *p++ = '\0';    /* mark end and point to next option */
                }
                nextop = p;
                p = strchr(s, '=');     /* look for value */
                if (p == NULL) {
                        valp = NULL;    /* no value supplied */
                        ep = NULL;
                } else {
                        ep = p;         /* save location of equals */
                        *p++ = '\0';    /* end option and point to value */
                        valp = p;
                }
                /*
                 * set option into options table
                 */
                if (create)
                        setflg |= VFS_CREATEOPT;
                vfs_setmntopt_nolock(mops, s, valp, setflg, 0);
                if (cp != NULL)
                        *cp = ',';      /* restore the comma */
                if (valp != NULL)
                        *ep = '=';      /* restore the equals */
                s = nextop;
        }
}

/*
 * Function to inquire if an option exists in a mount options table.
 * Returns a pointer to the option if it exists, else NULL.
 */
struct mntopt *
vfs_hasopt(const mntopts_t *mops, const char *opt)
{
        struct mntopt *mop;
        uint_t i, count;

        count = mops->mo_count;
        for (i = 0; i < count; i++) {
                mop = &mops->mo_list[i];

                if (mop->mo_flags & MO_EMPTY)
                        continue;
                if (strcmp(opt, mop->mo_name) == 0)
                        return (mop);
        }
        return (NULL);
}

/*
 * Function to inquire if an option is set in a mount options table.
 * Returns non-zero if set and fills in the arg pointer with a pointer to
 * the argument string or NULL if there is no argument string.
 */
static int
vfs_optionisset_nolock(const mntopts_t *mops, const char *opt, char **argp)
{
        struct mntopt *mop;
        uint_t i, count;

        count = mops->mo_count;
        for (i = 0; i < count; i++) {
                mop = &mops->mo_list[i];

                if (mop->mo_flags & MO_EMPTY)
                        continue;
                if (strcmp(opt, mop->mo_name))
                        continue;
                if ((mop->mo_flags & MO_SET) == 0)
                        return (0);
                if (argp != NULL && (mop->mo_flags & MO_HASVALUE) != 0)
                        *argp = mop->mo_arg;
                return (1);
        }
        return (0);
}


int
vfs_optionisset(const struct vfs *vfsp, const char *opt, char **argp)
{
        int ret;

        vfs_list_read_lock();
        ret = vfs_optionisset_nolock(&vfsp->vfs_mntopts, opt, argp);
        vfs_list_unlock();
        return (ret);
}


/*
 * Construct a comma separated string of the options set in the given
 * mount table, return the string in the given buffer.  Return non-zero if
 * the buffer would overflow.
 *
 * This function is *not* for general use by filesystems.
 *
 * Note: caller is responsible for locking the vfs list, if needed,
 *       to protect mp.
 */
int
vfs_buildoptionstr(const mntopts_t *mp, char *buf, int len)
{
        char *cp;
        uint_t i;

        buf[0] = '\0';
        cp = buf;
        for (i = 0; i < mp->mo_count; i++) {
                struct mntopt *mop;

                mop = &mp->mo_list[i];
                if (mop->mo_flags & MO_SET) {
                        int optlen, comma = 0;

                        if (buf[0] != '\0')
                                comma = 1;
                        optlen = strlen(mop->mo_name);
                        if (strlen(buf) + comma + optlen + 1 > len)
                                goto err;
                        if (comma)
                                *cp++ = ',';
                        (void) strcpy(cp, mop->mo_name);
                        cp += optlen;
                        /*
                         * Append option value if there is one
                         */
                        if (mop->mo_arg != NULL) {
                                int arglen;

                                arglen = strlen(mop->mo_arg);
                                if (strlen(buf) + arglen + 2 > len)
                                        goto err;
                                *cp++ = '=';
                                (void) strcpy(cp, mop->mo_arg);
                                cp += arglen;
                        }
                }
        }
        return (0);
err:
        return (EOVERFLOW);
}

static void
vfs_freecancelopt(char **moc)
{
        if (moc != NULL) {
                int ccnt = 0;
                char **cp;

                for (cp = moc; *cp != NULL; cp++) {
                        kmem_free(*cp, strlen(*cp) + 1);
                        ccnt++;
                }
                kmem_free(moc, (ccnt + 1) * sizeof (char *));
        }
}

static void
vfs_freeopt(mntopt_t *mop)
{
        if (mop->mo_name != NULL)
                kmem_free(mop->mo_name, strlen(mop->mo_name) + 1);

        vfs_freecancelopt(mop->mo_cancel);

        if (mop->mo_arg != NULL)
                kmem_free(mop->mo_arg, strlen(mop->mo_arg) + 1);
}

/*
 * Free a mount options table
 *
 * This function is *not* for general use by filesystems.
 *
 * Note: caller is responsible for locking the vfs list, if needed,
 *       to protect mp.
 */
void
vfs_freeopttbl(mntopts_t *mp)
{
        uint_t i, count;

        count = mp->mo_count;
        for (i = 0; i < count; i++) {
                vfs_freeopt(&mp->mo_list[i]);
        }
        if (count) {
                kmem_free(mp->mo_list, sizeof (mntopt_t) * count);
                mp->mo_count = 0;
                mp->mo_list = NULL;
        }
}

// vfs_mntdummyread
// vfs_mntdummywrite
// vfs_mntdummygetattr
// vfs_mnttabvp_setup
// vfs_mnttab_rwop
// vfs_mnttab_writeop
// vfs_mnttab_readop
// vfs_freemnttab
// vfs_mnttab_modtime
// vfs_mnttab_poll
// vfs_mono_time

/*
 * Update the mnttab modification time...
 */
void
vfs_mnttab_modtimeupd()
{
}

/*
 * Unlike the real dounmount, we don't have
 * vn_vfswlock_held(coveredvp)
 */
int
fake_dounmount(struct vfs *vfsp, int flag)
{
        cred_t *cr = CRED();
        vnode_t *coveredvp;
        int error;

        /*
         * Get covered vnode. This will be NULL if the vfs is not linked
         * into the file system name space (i.e., domount() with MNT_NOSPICE).
         */
        coveredvp = vfsp->vfs_vnodecovered;

        /* For forcible umount, skip VFS_SYNC() since it may hang */
        if ((flag & MS_FORCE) == 0)
                (void) VFS_SYNC(vfsp, 0, cr);

        /*
         * Test-jig specific:
         * Need to release rootdir before unmount or VFS_UNMOUNT
         * may fail due to that node being active.
         */
        if (rootdir != NULL) {
                ASSERT(rootdir != coveredvp);
                VN_RELE(rootdir);
                rootdir = NULL;
        }

        /*
         * Lock the vfs to maintain fs status quo during unmount.  This
         * has to be done after the sync because ufs_update tries to acquire
         * the vfs_reflock.
         */
        vfs_lock_wait(vfsp);

        if ((error = VFS_UNMOUNT(vfsp, flag, cr)) != 0) {
                int err2;
                vfs_unlock(vfsp);
                /* Get rootdir back */
                err2 = VFS_ROOT(vfsp, &rootdir);
                if (err2 != 0) {
                        panic("fake_dounmount, get root %d\n", err2);
                }
        } else {
                /*
                 * Real dounmount does vfs_remove.
                 *
                 * Test-jig specific:
                 * Restore the covered rootdir,
                 * release the rootvfs hold and clear.
                 */
                if (coveredvp != NULL) {
                        // vfs_list_remove(vfsp);
                        vfsp->vfs_vnodecovered = NULL;
                        rootdir = coveredvp;
                }
                if (rootvfs == vfsp) {
                        VFS_RELE(vfsp);
                        rootvfs = NULL;
                }

                /*
                 * Release the (final) reference to vfs
                 */
                vfs_unlock(vfsp);
                VFS_RELE(vfsp);
        }
        return (error);
}

// vfs_unmountall(void)
// vfs_addmip
// vfs_delmip
// vfs_add
// vfs_remove

static krwlock_t vpvfsentry_ve_lock;

/*
 * Lock a filesystem to prevent access to it while mounting,
 * unmounting and syncing.  Return EBUSY immediately if lock
 * can't be acquired.
 */
int
vfs_lock(vfs_t *vfsp)
{

        if (rw_tryenter(&vpvfsentry_ve_lock, RW_WRITER))
                return (0);

        return (EBUSY);
}

int
vfs_rlock(vfs_t *vfsp)
{

        if (rw_tryenter(&vpvfsentry_ve_lock, RW_READER))
                return (0);

        return (EBUSY);
}

void
vfs_lock_wait(vfs_t *vfsp)
{

        rw_enter(&vpvfsentry_ve_lock, RW_WRITER);
}

void
vfs_rlock_wait(vfs_t *vfsp)
{
        rw_enter(&vpvfsentry_ve_lock, RW_READER);
}

/*
 * Unlock a locked filesystem.
 */
void
vfs_unlock(vfs_t *vfsp)
{

        rw_exit(&vpvfsentry_ve_lock);
}

/*
 * Utility routine that allows a filesystem to construct its
 * fsid in "the usual way" - by munging some underlying dev_t and
 * the filesystem type number into the 64-bit fsid. ...
 */
void
vfs_make_fsid(fsid_t *fsi, dev_t dev, int val)
{
        if (!cmpldev((dev32_t *)&fsi->val[0], dev))
                panic("device number too big for fsid!");
        fsi->val[1] = val;
}

int
vfs_lock_held(vfs_t *vfsp)
{
        int held;

        held = rw_write_held(&vpvfsentry_ve_lock);

        return (held);
}

// vfs_lock_owner

/*
 * vfs list locking.
 */

void
vfs_list_lock()
{
        rw_enter(&vfslist, RW_WRITER);
}

void
vfs_list_read_lock()
{
        rw_enter(&vfslist, RW_READER);
}

void
vfs_list_unlock()
{
        rw_exit(&vfslist);
}

/*
 * Low level worker routines for adding entries to and removing entries from
 * the vfs list.
 */

// vfs_hash_add
// vfs_hash_remove
// vfs_list_add
// vfs_list_remove
// getvfs
// vfs_devmounting

/*
 * Search the vfs list for a specified device.  Returns 1, if entry is found
 * or 0 if no suitable entry is found.
 */

int
vfs_devismounted(dev_t dev)
{
        return (0);
}

// vfs_dev2vfsp
// vfs_mntpoint2vfsp

/*
 * Search the vfs list for a specified vfsops.
 * if vfs entry is found then return 1, else 0.
 */
int
vfs_opsinuse(vfsops_t *ops)
{
        return (0);
}

/*
 * Allocate an entry in vfssw for a file system type
 */
struct vfssw *
allocate_vfssw(const char *type)
{
        struct vfssw *vswp;

        if (type[0] == '\0' || strlen(type) + 1 > _ST_FSTYPSZ) {
                /*
                 * The vfssw table uses the empty string to identify an
                 * available entry; we cannot add any type which has
                 * a leading NUL. The string length is limited to
                 * the size of the st_fstype array in struct stat.
                 */
                return (NULL);
        }

        ASSERT(VFSSW_WRITE_LOCKED());
        for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++)
                if (!ALLOCATED_VFSSW(vswp)) {
                        vswp->vsw_name = kmem_alloc(strlen(type) + 1, KM_SLEEP);
                        (void) strcpy(vswp->vsw_name, type);
                        ASSERT(vswp->vsw_count == 0);
                        vswp->vsw_count = 1;
                        mutex_init(&vswp->vsw_lock, NULL, MUTEX_DEFAULT, NULL);
                        return (vswp);
                }
        return (NULL);
}

// vfs_to_modname
// vfs_getvfssw

/*
 * Find a vfssw entry given a file system type name.
 */
struct vfssw *
vfs_getvfssw(const char *type)
{
        struct vfssw *vswp;

        if (type == NULL || *type == '\0')
                return (NULL);

        for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
                if (strcmp(type, vswp->vsw_name) == 0) {
                        return (vswp);
                }
        }

        return (NULL);

}

/*
 * Find a vfssw entry given a file system type name.
 */
struct vfssw *
vfs_getvfsswbyname(const char *type)
{
        struct vfssw *vswp;

        ASSERT(VFSSW_LOCKED());
        if (type == NULL || *type == '\0')
                return (NULL);

        for (vswp = &vfssw[1]; vswp < &vfssw[nfstype]; vswp++) {
                if (strcmp(type, vswp->vsw_name) == 0) {
                        vfs_refvfssw(vswp);
                        return (vswp);
                }
        }

        return (NULL);
}

// vfs_getvfsswbyvfsops

/*
 * Reference a vfssw entry.
 */
void
vfs_refvfssw(struct vfssw *vswp)
{

        mutex_enter(&vswp->vsw_lock);
        vswp->vsw_count++;
        mutex_exit(&vswp->vsw_lock);
}

/*
 * Unreference a vfssw entry.
 */
void
vfs_unrefvfssw(struct vfssw *vswp)
{

        mutex_enter(&vswp->vsw_lock);
        vswp->vsw_count--;
        mutex_exit(&vswp->vsw_lock);
}

// vfs_syncall

/*
 * Map VFS flags to statvfs flags.  These shouldn't really be separate
 * flags at all.
 */
uint_t
vf_to_stf(uint_t vf)
{
        uint_t stf = 0;

        if (vf & VFS_RDONLY)
                stf |= ST_RDONLY;
        if (vf & VFS_NOSETUID)
                stf |= ST_NOSUID;
        if (vf & VFS_NOTRUNC)
                stf |= ST_NOTRUNC;

        return (stf);
}

// vfsstray_sync
// vfsstray
// vfs_EIO
// vfs_EIO_sync
// EIO_vfs
// EIO_vfsops

#pragma init(vfsinit)

/*
 * Called from startup() to initialize all loaded vfs's
 */
void
vfsinit(void)
{
        vn_create_cache();

        /* Temporary, until we mount root */
        rootdir = vn_alloc(KM_SLEEP);
        rootdir->v_type = VDIR;
}

vfs_t *
vfs_alloc(int kmflag)
{
        vfs_t *vfsp;

        vfsp = kmem_alloc(sizeof (struct vfs), kmflag);

        /*
         * Do the simplest initialization here.
         * Everything else gets done in vfs_init()
         */
        bzero(vfsp, sizeof (vfs_t));
        return (vfsp);
}

void
vfs_free(vfs_t *vfsp)
{
        /*
         * One would be tempted to assert that "vfsp->vfs_count == 0".
         * Don't.  See fs/vfs.c
         */

        /* If FEM was in use, make sure everything gets cleaned up */

        if (vfsp->vfs_implp)
                vfsimpl_teardown(vfsp);
        sema_destroy(&vfsp->vfs_reflock);
        kmem_free(vfsp, sizeof (struct vfs));
}

/*
 * Increments the vfs reference count by one atomically.
 */
void
vfs_hold(vfs_t *vfsp)
{
        atomic_inc_32(&vfsp->vfs_count);
        ASSERT(vfsp->vfs_count != 0);
}

/*
 * Decrements the vfs reference count by one atomically. When
 * vfs reference count becomes zero, it calls the file system
 * specific vfs_freevfs() to free up the resources.
 */
void
vfs_rele(vfs_t *vfsp)
{
        ASSERT(vfsp->vfs_count != 0);
        if (atomic_dec_32_nv(&vfsp->vfs_count) == 0) {
                VFS_FREEVFS(vfsp);
                // lofi_remove(vfsp);
                // zone_rele_ref...
                // vfs_freemnttab(vfsp);
                vfs_free(vfsp);
        }
}

/*
 * Generic operations vector support.
 */

int
fs_build_vector(void *vector, int *unused_ops,
    const fs_operation_trans_def_t *translation,
    const fs_operation_def_t *operations)
{
        int i, num_trans, num_ops, used;

        /*
         * Count the number of translations and the number of supplied
         * operations.
         */

        {
                const fs_operation_trans_def_t *p;

                for (num_trans = 0, p = translation;
                    p->name != NULL;
                    num_trans++, p++)
                        ;
        }

        {
                const fs_operation_def_t *p;

                for (num_ops = 0, p = operations;
                    p->name != NULL;
                    num_ops++, p++)
                        ;
        }

        /* Walk through each operation known to our caller.  There will be */
        /* one entry in the supplied "translation table" for each. */

        used = 0;

        for (i = 0; i < num_trans; i++) {
                int j, found;
                char *curname;
                fs_generic_func_p result;
                fs_generic_func_p *location;

                curname = translation[i].name;

                /* Look for a matching operation in the list supplied by the */
                /* file system. */

                found = 0;

                for (j = 0; j < num_ops; j++) {
                        if (strcmp(operations[j].name, curname) == 0) {
                                used++;
                                found = 1;
                                break;
                        }
                }

                /*
                 * If the file system is using a "placeholder" for default
                 * or error functions, grab the appropriate function out of
                 * the translation table.  If the file system didn't supply
                 * this operation at all, use the default function.
                 */

                if (found) {
                        result = operations[j].func.fs_generic;
                        if (result == fs_default) {
                                result = translation[i].defaultFunc;
                        } else if (result == fs_error) {
                                result = translation[i].errorFunc;
                        } else if (result == NULL) {
                                /* Null values are PROHIBITED */
                                return (EINVAL);
                        }
                } else {
                        result = translation[i].defaultFunc;
                }

                /* Now store the function into the operations vector. */

                /* LINTED E_BAD_PTR_CAST_ALIGN */
                location = (fs_generic_func_p *)
                    (((char *)vector) + translation[i].offset);

                *location = result;
        }

        *unused_ops = num_ops - used;

        return (0);
}

/* Placeholder functions, should never be called. */

int
fs_error(void)
{
        cmn_err(CE_PANIC, "fs_error called");
        return (0);
}

int
fs_default(void)
{
        cmn_err(CE_PANIC, "fs_default called");
        return (0);
}

// rootconf
// getfsname
// getrootfs

/*
 * VFS feature routines
 */

#define VFTINDEX(feature)       (((feature) >> 32) & 0xFFFFFFFF)
#define VFTBITS(feature)        ((feature) & 0xFFFFFFFFLL)

/* Register a feature in the vfs */
void
vfs_set_feature(vfs_t *vfsp, vfs_feature_t feature)
{
        /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
        if (vfsp->vfs_implp == NULL)
                return;

        vfsp->vfs_featureset[VFTINDEX(feature)] |= VFTBITS(feature);
}

void
vfs_clear_feature(vfs_t *vfsp, vfs_feature_t feature)
{
        /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
        if (vfsp->vfs_implp == NULL)
                return;
        vfsp->vfs_featureset[VFTINDEX(feature)] &= VFTBITS(~feature);
}

/*
 * Query a vfs for a feature.
 * Returns 1 if feature is present, 0 if not
 */
int
vfs_has_feature(vfs_t *vfsp, vfs_feature_t feature)
{
        int     ret = 0;

        /* Note that vfs_featureset[] is found in *vfsp->vfs_implp */
        if (vfsp->vfs_implp == NULL)
                return (ret);

        if (vfsp->vfs_featureset[VFTINDEX(feature)] & VFTBITS(feature))
                ret = 1;

        return (ret);
}

// vfs_propagate_features
// vfs_get_lofi