xnu-6153.141.1.tar.gz

[apple/xnu.git] / bsd / miscfs / nullfs / null_vfsops.c

diff --git a/bsd/miscfs/nullfs/null_vfsops.c b/bsd/miscfs/nullfs/null_vfsops.c
index e81c6405959b0d57a340f7c12003c8a78a68e343..8305be1c60a0a16ad1c06e976887134c7a1d618f 100644 (file)
--- a/bsd/miscfs/nullfs/null_vfsops.c
+++ b/bsd/miscfs/nullfs/null_vfsops.c
@@ -1,20 +1,15 @@
 /*
 /*

- * Copyright (c) 2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2019 Apple Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@

  *
  *

- * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
- * 

  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in

- * compliance with the License. The rights granted to you under the License
- * may not be used to create, or enable the creation or redistribution of,
- * unlawful or unlicensed copies of an Apple operating system, or to
- * circumvent, violate, or enable the circumvention or violation of, any
- * terms of an Apple operating system software license agreement.
- * 
- * Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this file.
- * 
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ *

  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,


@@ -22,13 +17,13 @@
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  * Please see the License for the specific language governing rights and
  * limitations under the License.

- * 
- * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
+ *
+ * @APPLE_LICENSE_HEADER_END@

  */
  */

-/* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */
-/*
- * Copyright (c) 1992, 1993
- *     The Regents of the University of California.  All rights reserved.
+
+/*-
+ * Portions Copyright (c) 1992, 1993, 1995
+ *  The Regents of the University of California.  All rights reserved.

  *
  * This code is derived from software donated to Berkeley by
  * Jan-Simon Pendry.
  *
  * This code is derived from software donated to Berkeley by
  * Jan-Simon Pendry.


@@ -41,10 +36,6 @@
  * 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.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.

- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *     This product includes software developed by the University of
- *     California, Berkeley and its contributors.

  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  * 4. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.


@@ -61,322 +52,517 @@
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  *

- *     @(#)null_vfsops.c       8.7 (Berkeley) 5/14/95
+ *  @(#)null_vfsops.c   8.2 (Berkeley) 1/21/94

  *
  *

- * @(#)lofs_vfsops.c   1.2 (Berkeley) 6/18/92
- */
-
-/*
- * Null Layer
- * (See null_vnops.c for a description of what this does.)
+ * @(#)lofs_vfsops.c    1.2 (Berkeley) 6/18/92
+ * $FreeBSD$

  */
 
 #include <sys/param.h>
 #include <sys/systm.h>
  */
 
 #include <sys/param.h>
 #include <sys/systm.h>

+#include <sys/fcntl.h>
+#include <sys/kernel.h>
+#include <sys/lock.h>
+#include <sys/malloc.h>
+#include <sys/mount.h>
+#include <sys/namei.h>

 #include <sys/proc.h>
 #include <sys/proc.h>

-#include <sys/kauth.h>
-#include <sys/time.h>
-#include <sys/types.h>

 #include <sys/vnode.h>
 #include <sys/vnode.h>

-#include <sys/mount_internal.h>
-#include <sys/namei.h>
-#include <sys/malloc.h>
-#include <miscfs/nullfs/null.h>
+#include <sys/vnode_internal.h>
+#include <security/mac_internal.h>
+
+#include <sys/param.h>
+
+#include <IOKit/IOBSD.h>
+
+#include "nullfs.h"
+
+#define NULLFS_ENTITLEMENT "com.apple.private.nullfs_allow"
+
+#define SIZEOF_MEMBER(type, member) (sizeof(((type *)0)->member))
+#define MAX_MNT_FROM_LENGTH (SIZEOF_MEMBER(struct vfsstatfs, f_mntfromname))
+
+static int
+nullfs_vfs_getlowerattr(mount_t mp, struct vfs_attr * vfap, vfs_context_t ctx)
+{
+       memset(vfap, 0, sizeof(*vfap));
+       VFSATTR_INIT(vfap);
+       VFSATTR_WANTED(vfap, f_bsize);
+       VFSATTR_WANTED(vfap, f_iosize);
+       VFSATTR_WANTED(vfap, f_blocks);
+       VFSATTR_WANTED(vfap, f_bfree);
+       VFSATTR_WANTED(vfap, f_bavail);
+       VFSATTR_WANTED(vfap, f_bused);
+       VFSATTR_WANTED(vfap, f_files);
+       VFSATTR_WANTED(vfap, f_ffree);
+       VFSATTR_WANTED(vfap, f_capabilities);
+
+       return vfs_getattr(mp, vfap, ctx);
+}

 
 /*
  * Mount null layer
  */
 static int
 
 /*
  * Mount null layer
  */
 static int

-nullfs_mount(mp, devvp, data, context)
-       struct mount *mp;
-       vnode_t devvp;
-       user_addr_t data;
-       vfs_context_t context;
+nullfs_mount(struct mount * mp, __unused vnode_t devvp, user_addr_t user_data, vfs_context_t ctx)

 {
 {

-       int error = 0;
-       struct user_null_args args;
-       struct vnode *lowerrootvp, *vp;
-       struct vnode *nullm_rootvp;
-       struct null_mount *xmp;
-       u_int size;
-
-#ifdef NULLFS_DIAGNOSTIC
-       printf("nullfs_mount(mp = %x)\n", mp);
-#endif
+       int error                 = 0;
+       struct vnode *lowerrootvp = NULL, *vp = NULL;
+       struct vfsstatfs * sp   = NULL;
+       struct null_mount * xmp = NULL;
+       char data[MAXPATHLEN];
+       size_t count;
+       struct vfs_attr vfa;
+       /* set defaults (arbitrary since this file system is readonly) */
+       uint32_t bsize  = BLKDEV_IOSIZE;
+       size_t iosize   = BLKDEV_IOSIZE;
+       uint64_t blocks = 4711 * 4711;
+       uint64_t bfree  = 0;
+       uint64_t bavail = 0;
+       uint64_t bused  = 4711;
+       uint64_t files  = 4711;
+       uint64_t ffree  = 0;
+
+       kauth_cred_t cred = vfs_context_ucred(ctx);
+
+       NULLFSDEBUG("nullfs_mount(mp = %p) %llx\n", (void *)mp, vfs_flags(mp));
+
+       if (vfs_flags(mp) & MNT_ROOTFS) {
+               return EOPNOTSUPP;
+       }

 
        /*
         * Update is a no-op
         */
 
        /*
         * Update is a no-op
         */

-       if (mp->mnt_flag & MNT_UPDATE) {
-               return (ENOTSUP);
-               /* return VFS_MOUNT(MOUNTTONULLMOUNT(mp)->nullm_vfs, devvp, data,  p);*/
+       if (vfs_isupdate(mp)) {
+               return ENOTSUP;
+       }
+
+       /* check entitlement */
+       if (!IOTaskHasEntitlement(current_task(), NULLFS_ENTITLEMENT)) {
+               return EPERM;

        }
 
        /*
         * Get argument
         */
        }
 
        /*
         * Get argument
         */

-       if (vfs_context_is64bit(context)) {
-               error = copyin(data, (caddr_t)&args, sizeof (args));
+       error = copyinstr(user_data, data, MAXPATHLEN - 1, &count);
+       if (error) {
+               NULLFSDEBUG("nullfs: error copying data form user %d\n", error);
+               goto error;

        }
        }

-       else {
-               struct null_args temp;
-               error = copyin(data, (caddr_t)&temp, sizeof (temp));
-               args.target = CAST_USER_ADDR_T(temp.target);
+
+       /* This could happen if the system is configured for 32 bit inodes instead of
+        * 64 bit */
+       if (count > MAX_MNT_FROM_LENGTH) {
+               error = EINVAL;
+               NULLFSDEBUG("nullfs: path to translocate too large for this system %d vs %d\n", count, MAX_MNT_FROM_LENGTH);
+               goto error;

        }
        }

-       if (error)
-               return (error);

 
 

-       /*
-        * Find lower node
-        */
-       NDINIT(ndp, LOOKUP, FOLLOW|WANTPARENT|LOCKLEAF,
-               UIO_USERSPACE, args.target, context);
-       if (error = namei(ndp))
-               return (error);
-       nameidone(ndp);
-       /*
-        * Sanity check on lower vnode
-        */
-       lowerrootvp = ndp->ni_vp;
+       error = vnode_lookup(data, 0, &lowerrootvp, ctx);
+       if (error) {
+               NULLFSDEBUG("lookup %s -> %d\n", data, error);
+               goto error;
+       }
+
+       /* lowervrootvp has an iocount after vnode_lookup, drop that for a usecount.
+        *  Keep this to signal what we want to keep around the thing we are mirroring.
+        *  Drop it in unmount.*/
+       error = vnode_ref(lowerrootvp);
+       vnode_put(lowerrootvp);
+       if (error) {
+               // If vnode_ref failed, then null it out so it can't be used anymore in cleanup.
+               lowerrootvp = NULL;
+               goto error;
+       }

 
 

-       vnode_put(ndp->ni_dvp);
-       ndp->ni_dvp = NULL;
+       NULLFSDEBUG("mount %s\n", data);

 
 

-       xmp = (struct null_mount *) _MALLOC(sizeof(struct null_mount),
-                               M_UFSMNT, M_WAITOK);    /* XXX */
+       MALLOC(xmp, struct null_mount *, sizeof(*xmp), M_TEMP, M_WAITOK | M_ZERO);
+       if (xmp == NULL) {
+               error = ENOMEM;
+               goto error;
+       }

 
        /*
         * Save reference to underlying FS
         */
 
        /*
         * Save reference to underlying FS
         */

-       xmp->nullm_vfs = lowerrootvp->v_mount;
+       xmp->nullm_lowerrootvp  = lowerrootvp;
+       xmp->nullm_lowerrootvid = vnode_vid(lowerrootvp);

 
 

-       /*
-        * Save reference.  Each mount also holds
-        * a reference on the root vnode.
-        */
-       error = null_node_create(mp, lowerrootvp, &vp);
-       /*
-        * Make sure the node alias worked
-        */
+       error = null_getnewvnode(mp, NULL, NULL, &vp, NULL, 1);

        if (error) {
        if (error) {

-               vnode_put(lowerrootvp);
-               FREE(xmp, M_UFSMNT);    /* XXX */
-               return (error);
+               goto error;

        }
 
        }
 

-       /*
-        * Keep a held reference to the root vnode.
-        * It is vnode_put'd in nullfs_unmount.
-        */
-       nullm_rootvp = vp;
-       nullm_rootvp->v_flag |= VROOT;
-       xmp->nullm_rootvp = nullm_rootvp;
-       if (NULLVPTOLOWERVP(nullm_rootvp)->v_mount->mnt_flag & MNT_LOCAL)
-               mp->mnt_flag |= MNT_LOCAL;
-       mp->mnt_data = (qaddr_t) xmp;
+       /* vp has an iocount on it from vnode_create. drop that for a usecount. This
+        * is our root vnode so we drop the ref in unmount
+        *
+        * Assuming for now that because we created this vnode and we aren't finished mounting we can get a ref*/
+       vnode_ref(vp);
+       vnode_put(vp);
+
+       error = nullfs_init_lck(&xmp->nullm_lock);
+       if (error) {
+               goto error;
+       }
+
+       xmp->nullm_rootvp = vp;
+
+       /* read the flags the user set, but then ignore some of them, we will only
+        *  allow them if they are set on the lower file system */
+       uint64_t flags      = vfs_flags(mp) & (~(MNT_IGNORE_OWNERSHIP | MNT_LOCAL));
+       uint64_t lowerflags = vfs_flags(vnode_mount(lowerrootvp)) & (MNT_LOCAL | MNT_QUARANTINE | MNT_IGNORE_OWNERSHIP | MNT_NOEXEC);
+
+       if (lowerflags) {
+               flags |= lowerflags;
+       }
+
+       /* force these flags */
+       flags |= (MNT_DONTBROWSE | MNT_MULTILABEL | MNT_NOSUID | MNT_RDONLY);
+       vfs_setflags(mp, flags);
+
+       vfs_setfsprivate(mp, xmp);

        vfs_getnewfsid(mp);
        vfs_getnewfsid(mp);

+       vfs_setlocklocal(mp);
+
+       /* fill in the stat block */
+       sp = vfs_statfs(mp);
+       strlcpy(sp->f_mntfromname, data, MAX_MNT_FROM_LENGTH);
+
+       sp->f_flags = flags;
+
+       xmp->nullm_flags = NULLM_CASEINSENSITIVE; /* default to case insensitive */
+
+       error = nullfs_vfs_getlowerattr(vnode_mount(lowerrootvp), &vfa, ctx);
+       if (error == 0) {
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_bsize)) {
+                       bsize = vfa.f_bsize;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_iosize)) {
+                       iosize = vfa.f_iosize;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_blocks)) {
+                       blocks = vfa.f_blocks;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_bfree)) {
+                       bfree = vfa.f_bfree;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_bavail)) {
+                       bavail = vfa.f_bavail;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_bused)) {
+                       bused = vfa.f_bused;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_files)) {
+                       files = vfa.f_files;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_ffree)) {
+                       ffree = vfa.f_ffree;
+               }
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_capabilities)) {
+                       if ((vfa.f_capabilities.capabilities[VOL_CAPABILITIES_FORMAT] & (VOL_CAP_FMT_CASE_SENSITIVE)) &&
+                           (vfa.f_capabilities.valid[VOL_CAPABILITIES_FORMAT] & (VOL_CAP_FMT_CASE_SENSITIVE))) {
+                               xmp->nullm_flags &= ~NULLM_CASEINSENSITIVE;
+                       }
+               }
+       } else {
+               goto error;
+       }

 
 

-       (void) copyinstr(args.target, mp->mnt_vfsstat.f_mntfromname, MAXPATHLEN - 1, 
-           &size);
-       bzero(mp->mnt_vfsstat.f_mntfromname + size, MNAMELEN - size);
-#ifdef NULLFS_DIAGNOSTIC
-       printf("nullfs_mount: lower %s, alias at %s\n",
-               mp->mnt_vfsstat.f_mntfromname, mp->mnt_vfsstat.f_mntonname);
-#endif
-       return (0);
-}
+       sp->f_bsize  = bsize;
+       sp->f_iosize = iosize;
+       sp->f_blocks = blocks;
+       sp->f_bfree  = bfree;
+       sp->f_bavail = bavail;
+       sp->f_bused  = bused;
+       sp->f_files  = files;
+       sp->f_ffree  = ffree;

 
 

-/*
- * VFS start.  Nothing needed here - the start routine
- * on the underlying filesystem will have been called
- * when that filesystem was mounted.
- */
-static int
-nullfs_start(mp, flags, context)
-       struct mount *mp;
-       int flags;
-       vfs_context_t context;
-{
-       return (0);
-       /* return VFS_START(MOUNTTONULLMOUNT(mp)->nullm_vfs, flags, context); */
+       /* Associate the mac label information from the mirrored filesystem with the
+        * mirror */
+       MAC_PERFORM(mount_label_associate, cred, vnode_mount(lowerrootvp), vfs_mntlabel(mp));
+
+       NULLFSDEBUG("nullfs_mount: lower %s, alias at %s\n", sp->f_mntfromname, sp->f_mntonname);
+       return 0;
+
+error:
+       if (xmp) {
+               FREE(xmp, M_TEMP);
+       }
+       if (lowerrootvp) {
+               vnode_getwithref(lowerrootvp);
+               vnode_rele(lowerrootvp);
+               vnode_put(lowerrootvp);
+       }
+       if (vp) {
+               /* we made the root vnode but the mount is failed, so clean it up */
+               vnode_getwithref(vp);
+               vnode_rele(vp);
+               /* give vp back */
+               vnode_recycle(vp);
+               vnode_put(vp);
+       }
+       return error;

 }
 
 /*
  * Free reference to null layer
  */
 static int
 }
 
 /*
  * Free reference to null layer
  */
 static int

-nullfs_unmount(mp, mntflags, context)
-       struct mount *mp;
-       int mntflags;
-       vfs_context_t context;
+nullfs_unmount(struct mount * mp, int mntflags, __unused vfs_context_t ctx)

 {
 {

-       struct vnode *nullm_rootvp = MOUNTTONULLMOUNT(mp)->nullm_rootvp;
-       int error;
-       int flags = 0;
-       int force = 0;
+       struct null_mount * mntdata;
+       struct vnode * vp;
+       int error, flags;

 
 

-#ifdef NULLFS_DIAGNOSTIC
-       printf("nullfs_unmount(mp = %x)\n", mp);
-#endif
+       NULLFSDEBUG("nullfs_unmount: mp = %p\n", (void *)mp);
+
+       /* check entitlement or superuser*/
+       if (!IOTaskHasEntitlement(current_task(), NULLFS_ENTITLEMENT) &&
+           vfs_context_suser(ctx) != 0) {
+               return EPERM;
+       }

 
        if (mntflags & MNT_FORCE) {
 
        if (mntflags & MNT_FORCE) {

-               flags |= FORCECLOSE;
-               force = 1;
+               flags = FORCECLOSE;
+       } else {
+               flags = 0;

        }
 
        }
 

-       if ( (nullm_rootvp->v_usecount > 1) && !force )
-               return (EBUSY);
-       if ( (error = vflush(mp, nullm_rootvp, flags)) && !force )
-               return (error);
+       mntdata = MOUNTTONULLMOUNT(mp);
+       vp      = mntdata->nullm_rootvp;
+
+       // release our reference on the root before flushing.
+       // it will get pulled out of the mount structure by reclaim
+       vnode_getalways(vp);
+
+       error = vflush(mp, vp, flags);
+       if (error) {
+               vnode_put(vp);
+               return error;
+       }
+
+       if (vnode_isinuse(vp, 1) && flags == 0) {
+               vnode_put(vp);
+               return EBUSY;
+       }
+
+       vnode_rele(vp); // Drop reference taken by nullfs_mount
+       vnode_put(vp); // Drop ref taken above
+
+       //Force close to get rid of the last vnode
+       (void)vflush(mp, NULL, FORCECLOSE);
+
+       /* no more vnodes, so tear down the mountpoint */
+
+       lck_mtx_lock(&mntdata->nullm_lock);
+
+       vfs_setfsprivate(mp, NULL);
+
+       vnode_getalways(mntdata->nullm_lowerrootvp);
+       vnode_rele(mntdata->nullm_lowerrootvp);
+       vnode_put(mntdata->nullm_lowerrootvp);
+
+       lck_mtx_unlock(&mntdata->nullm_lock);
+
+       nullfs_destroy_lck(&mntdata->nullm_lock);
+
+       FREE(mntdata, M_TEMP);
+
+       uint64_t vflags = vfs_flags(mp);
+       vfs_setflags(mp, vflags & ~MNT_LOCAL);

 
 

-#ifdef NULLFS_DIAGNOSTIC
-       vprint("alias root of lower", nullm_rootvp);
-#endif  
-       /*
-        * Release reference on underlying root vnode
-        */
-       vnode_put(nullm_rootvp);
-       /*
-        * And blow it away for future re-use
-        */
-       vnode_reclaim(nullm_rootvp);
-       /*
-        * Finally, throw away the null_mount structure
-        */
-       FREE(mp->mnt_data, M_UFSMNT);   /* XXX */
-       mp->mnt_data = 0;

        return 0;
 }
 
 static int
        return 0;
 }
 
 static int

-nullfs_root(mp, vpp, context)
-       struct mount *mp;
-       struct vnode **vpp;
-       vfs_context_t context;
+nullfs_root(struct mount * mp, struct vnode ** vpp, __unused vfs_context_t ctx)

 {
 {

-       struct proc *p = curproc;       /* XXX */
-       struct vnode *vp;
+       struct vnode * vp;
+       int error;

 
 

-#ifdef NULLFS_DIAGNOSTIC
-       printf("nullfs_root(mp = %x, vp = %x->%x)\n", mp,
-                       MOUNTTONULLMOUNT(mp)->nullm_rootvp,
-                       NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp)
-                       );
-#endif
+       NULLFSDEBUG("nullfs_root(mp = %p, vp = %p)\n", (void *)mp, (void *)MOUNTTONULLMOUNT(mp)->nullm_rootvp);

 
        /*
         * Return locked reference to root.
         */
        vp = MOUNTTONULLMOUNT(mp)->nullm_rootvp;
 
        /*
         * Return locked reference to root.
         */
        vp = MOUNTTONULLMOUNT(mp)->nullm_rootvp;

-       vnode_get(vp);
+
+       error = vnode_get(vp);
+       if (error) {
+               return error;
+       }
+

        *vpp = vp;
        return 0;
 }
 
 static int
        *vpp = vp;
        return 0;
 }
 
 static int

-nullfs_quotactl(mp, cmd, uid, datap, context)
-       struct mount *mp;
-       int cmd;
-       uid_t uid;
-       caddr_t datap;
-       vfs_context_t context;
+nullfs_vfs_getattr(struct mount * mp, struct vfs_attr * vfap, vfs_context_t ctx)

 {
 {

-       return VFS_QUOTACTL(MOUNTTONULLMOUNT(mp)->nullm_vfs, cmd, uid, datap, context);
-}
+       struct vnode * coveredvp = NULL;
+       struct vfs_attr vfa;
+       struct null_mount * null_mp = MOUNTTONULLMOUNT(mp);
+       vol_capabilities_attr_t capabilities;
+       struct vfsstatfs * sp = vfs_statfs(mp);

 
 

-static int
-nullfs_statfs(mp, sbp, context)
-       struct mount *mp;
-       struct vfsstatfs *sbp;
-       vfs_context_t context;
-{
-       int error;
-       struct vfsstatfs mstat;
-
-#ifdef NULLFS_DIAGNOSTIC
-       printf("nullfs_statfs(mp = %x, vp = %x->%x)\n", mp,
-                       MOUNTTONULLMOUNT(mp)->nullm_rootvp,
-                       NULLVPTOLOWERVP(MOUNTTONULLMOUNT(mp)->nullm_rootvp)
-                       );
-#endif
-
-       bzero(&mstat, sizeof(mstat));
-
-       error = VFS_STATFS(MOUNTTONULLMOUNT(mp)->nullm_vfs, &mstat, context);
-       if (error)
-               return (error);
-
-       /* now copy across the "interesting" information and fake the rest */
-       //sbp->f_type = mstat.f_type;
-       sbp->f_flags = mstat.f_flags;
-       sbp->f_bsize = mstat.f_bsize;
-       sbp->f_iosize = mstat.f_iosize;
-       sbp->f_blocks = mstat.f_blocks;
-       sbp->f_bfree = mstat.f_bfree;
-       sbp->f_bavail = mstat.f_bavail;
-       sbp->f_files = mstat.f_files;
-       sbp->f_ffree = mstat.f_ffree;
-       return (0);
+       struct timespec tzero = {.tv_sec = 0, .tv_nsec = 0};
+
+       NULLFSDEBUG("%s\n", __FUNCTION__);
+
+       /* Set default capabilities in case the lower file system is gone */
+       memset(&capabilities, 0, sizeof(capabilities));
+       capabilities.capabilities[VOL_CAPABILITIES_FORMAT] = VOL_CAP_FMT_FAST_STATFS | VOL_CAP_FMT_HIDDEN_FILES;
+       capabilities.valid[VOL_CAPABILITIES_FORMAT]        = VOL_CAP_FMT_FAST_STATFS | VOL_CAP_FMT_HIDDEN_FILES;
+
+       if (nullfs_vfs_getlowerattr(vnode_mount(null_mp->nullm_lowerrootvp), &vfa, ctx) == 0) {
+               if (VFSATTR_IS_SUPPORTED(&vfa, f_capabilities)) {
+                       memcpy(&capabilities, &vfa.f_capabilities, sizeof(capabilities));
+                       /* don't support vget */
+                       capabilities.capabilities[VOL_CAPABILITIES_FORMAT] &= ~(VOL_CAP_FMT_PERSISTENTOBJECTIDS | VOL_CAP_FMT_PATH_FROM_ID);
+
+                       capabilities.capabilities[VOL_CAPABILITIES_FORMAT] |= VOL_CAP_FMT_HIDDEN_FILES; /* Always support UF_HIDDEN */
+
+                       capabilities.valid[VOL_CAPABILITIES_FORMAT] &= ~(VOL_CAP_FMT_PERSISTENTOBJECTIDS | VOL_CAP_FMT_PATH_FROM_ID);
+
+                       capabilities.valid[VOL_CAPABILITIES_FORMAT] |= VOL_CAP_FMT_HIDDEN_FILES; /* Always support UF_HIDDEN */
+
+                       /* dont' support interfaces that only make sense on a writable file system
+                        * or one with specific vnops implemented */
+                       capabilities.capabilities[VOL_CAPABILITIES_INTERFACES] = 0;
+
+                       capabilities.valid[VOL_CAPABILITIES_INTERFACES] &=
+                           ~(VOL_CAP_INT_SEARCHFS | VOL_CAP_INT_ATTRLIST | VOL_CAP_INT_READDIRATTR | VOL_CAP_INT_EXCHANGEDATA |
+                           VOL_CAP_INT_COPYFILE | VOL_CAP_INT_ALLOCATE | VOL_CAP_INT_VOL_RENAME | VOL_CAP_INT_ADVLOCK | VOL_CAP_INT_FLOCK);
+               }
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_create_time)) {
+               VFSATTR_RETURN(vfap, f_create_time, tzero);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_modify_time)) {
+               VFSATTR_RETURN(vfap, f_modify_time, tzero);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_access_time)) {
+               VFSATTR_RETURN(vfap, f_access_time, tzero);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_bsize)) {
+               VFSATTR_RETURN(vfap, f_bsize, sp->f_bsize);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_iosize)) {
+               VFSATTR_RETURN(vfap, f_iosize, sp->f_iosize);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_owner)) {
+               VFSATTR_RETURN(vfap, f_owner, 0);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_blocks)) {
+               VFSATTR_RETURN(vfap, f_blocks, sp->f_blocks);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_bfree)) {
+               VFSATTR_RETURN(vfap, f_bfree, sp->f_bfree);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_bavail)) {
+               VFSATTR_RETURN(vfap, f_bavail, sp->f_bavail);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_bused)) {
+               VFSATTR_RETURN(vfap, f_bused, sp->f_bused);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_files)) {
+               VFSATTR_RETURN(vfap, f_files, sp->f_files);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_ffree)) {
+               VFSATTR_RETURN(vfap, f_ffree, sp->f_ffree);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_fssubtype)) {
+               VFSATTR_RETURN(vfap, f_fssubtype, 0);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_capabilities)) {
+               memcpy(&vfap->f_capabilities, &capabilities, sizeof(vol_capabilities_attr_t));
+
+               VFSATTR_SET_SUPPORTED(vfap, f_capabilities);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_attributes)) {
+               vol_attributes_attr_t * volattr = &vfap->f_attributes;
+
+               volattr->validattr.commonattr = 0;
+               volattr->validattr.volattr    = ATTR_VOL_NAME | ATTR_VOL_CAPABILITIES | ATTR_VOL_ATTRIBUTES;
+               volattr->validattr.dirattr    = 0;
+               volattr->validattr.fileattr   = 0;
+               volattr->validattr.forkattr   = 0;
+
+               volattr->nativeattr.commonattr = 0;
+               volattr->nativeattr.volattr    = ATTR_VOL_NAME | ATTR_VOL_CAPABILITIES | ATTR_VOL_ATTRIBUTES;
+               volattr->nativeattr.dirattr    = 0;
+               volattr->nativeattr.fileattr   = 0;
+               volattr->nativeattr.forkattr   = 0;
+
+               VFSATTR_SET_SUPPORTED(vfap, f_attributes);
+       }
+
+       if (VFSATTR_IS_ACTIVE(vfap, f_vol_name)) {
+               /* The name of the volume is the same as the directory we mounted on */
+               coveredvp = vfs_vnodecovered(mp);
+               if (coveredvp) {
+                       const char * name = vnode_getname_printable(coveredvp);
+                       strlcpy(vfap->f_vol_name, name, MAXPATHLEN);
+                       vnode_putname_printable(name);
+
+                       VFSATTR_SET_SUPPORTED(vfap, f_vol_name);
+                       vnode_put(coveredvp);
+               }
+       }
+
+       return 0;

 }
 
 static int
 }
 
 static int

-nullfs_sync(__unused struct mount *mp, __unused int waitfor,
-       __unused kauth_cred_t cred, __unused vfs_context_t context)
+nullfs_sync(__unused struct mount * mp, __unused int waitfor, __unused vfs_context_t ctx)

 {
        /*
         * XXX - Assumes no data cached at null layer.
         */
 {
        /*
         * XXX - Assumes no data cached at null layer.
         */

-       return (0);
-}
-
-static int
-nullfs_vget(mp, ino, vpp, context)
-       struct mount *mp;
-       ino64_t ino;
-       struct vnode **vpp;
-       vfs_context_t context;
-{
-       
-       return VFS_VGET(MOUNTTONULLMOUNT(mp)->nullm_vfs, ino, vpp, context);
+       return 0;

 }
 
 }
 

-static int
-nullfs_fhtovp(mp, fhlen, fhp, vpp, context)
-       struct mount *mp;
-       int fhlen;
-       unsigned char *fhp;
-       struct vnode **vpp;
-       vfs_context_t context;
-{

 
 

-       return VFS_FHTOVP(MOUNTTONULLMOUNT(mp)->nullm_vfs, fhlen, fhp, vpp, context);
-}

 
 static int
 
 static int

-nullfs_vptofh(vp, fhlenp, fhp, context)
-       struct vnode *vp;
-       int *fhlenp;
-       unsigned char *fhp;
-       vfs_context_t context;
+nullfs_vfs_start(__unused struct mount * mp, __unused int flags, __unused vfs_context_t ctx)

 {
 {

-       return VFS_VPTOFH(NULLVPTOLOWERVP(vp), fhlenp, fhp, context);
+       NULLFSDEBUG("%s\n", __FUNCTION__);
+       return 0;

 }
 
 }
 

-int nullfs_init (struct vfsconf *);
-
-#define nullfs_sysctl (int (*) (int *, u_int, user_addr_t, size_t *, user_addr_t, size_t, proc_t))eopnotsupp
-
-struct vfsops null_vfsops = {
-       nullfs_mount,
-       nullfs_start,
-       nullfs_unmount,
-       nullfs_root,
-       nullfs_quotactl,
-       nullfs_statfs,
-       nullfs_sync,
-       nullfs_vget,
-       nullfs_fhtovp,
-       nullfs_vptofh,
-       nullfs_init,
-       nullfs_sysctl
+extern const struct vnodeopv_desc nullfs_vnodeop_opv_desc;
+
+const struct vnodeopv_desc * nullfs_vnodeopv_descs[] = {
+       &nullfs_vnodeop_opv_desc,
+};
+
+struct vfsops nullfs_vfsops = {
+       .vfs_mount              = nullfs_mount,
+       .vfs_unmount            = nullfs_unmount,
+       .vfs_start              = nullfs_vfs_start,
+       .vfs_root               = nullfs_root,
+       .vfs_getattr            = nullfs_vfs_getattr,
+       .vfs_sync               = nullfs_sync,
+       .vfs_init               = nullfs_init,
+       .vfs_sysctl             = NULL,
+       .vfs_setattr            = NULL,

 };
 };