Logo Search packages:      
Sourcecode: kfreebsd-6 version File versions  Download package

vfs_syscalls.c

/*-
 * Copyright (c) 1989, 1993
 *    The Regents of the University of California.  All rights reserved.
 * (c) UNIX System Laboratories, Inc.
 * All or some portions of this file are derived from material licensed
 * to the University of California by American Telephone and Telegraph
 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 *
 * 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.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *    @(#)vfs_syscalls.c      8.13 (Berkeley) 4/15/94
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/kern/vfs_syscalls.c,v 1.392.2.19 2007/05/29 10:09:43 kib Exp $");

#include "opt_compat.h"
#include "opt_mac.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bio.h>
#include <sys/buf.h>
#include <sys/sysent.h>
#include <sys/mac.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/mutex.h>
#include <sys/sysproto.h>
#include <sys/namei.h>
#include <sys/filedesc.h>
#include <sys/kernel.h>
#include <sys/fcntl.h>
#include <sys/file.h>
#include <sys/limits.h>
#include <sys/linker.h>
#include <sys/stat.h>
#include <sys/sx.h>
#include <sys/unistd.h>
#include <sys/vnode.h>
#include <sys/proc.h>
#include <sys/dirent.h>
#include <sys/extattr.h>
#include <sys/jail.h>
#include <sys/syscallsubr.h>
#include <sys/sysctl.h>

#include <machine/stdarg.h>

#include <security/audit/audit.h>

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

static int chroot_refuse_vdir_fds(struct filedesc *fdp);
static int getutimes(const struct timeval *, enum uio_seg, struct timespec *);
static int setfown(struct thread *td, struct vnode *, uid_t, gid_t);
static int setfmode(struct thread *td, struct vnode *, int);
static int setfflags(struct thread *td, struct vnode *, int);
static int setutimes(struct thread *td, struct vnode *,
    const struct timespec *, int, int);
static int vn_access(struct vnode *vp, int user_flags, struct ucred *cred,
    struct thread *td);

static int extattr_list_vp(struct vnode *vp, int attrnamespace, void *data,
    size_t nbytes, struct thread *td);

/*
 * The module initialization routine for POSIX asynchronous I/O will
 * set this to the version of AIO that it implements.  (Zero means
 * that it is not implemented.)  This value is used here by pathconf()
 * and in kern_descrip.c by fpathconf().
 */
int async_io_version;

/*
 * Sync each mounted filesystem.
 */
#ifndef _SYS_SYSPROTO_H_
struct sync_args {
      int     dummy;
};
#endif

#ifdef DEBUG
static int syncprt = 0;
SYSCTL_INT(_debug, OID_AUTO, syncprt, CTLFLAG_RW, &syncprt, 0, "");
#endif

/* ARGSUSED */
int
sync(td, uap)
      struct thread *td;
      struct sync_args *uap;
{
      struct mount *mp, *nmp;
      int asyncflag;

      mtx_lock(&Giant);
      mtx_lock(&mountlist_mtx);
      for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
            if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) {
                  nmp = TAILQ_NEXT(mp, mnt_list);
                  continue;
            }
            if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
                vn_start_write(NULL, &mp, V_NOWAIT) == 0) {
                  MNT_ILOCK(mp);
                  asyncflag = mp->mnt_flag & MNT_ASYNC;
                  mp->mnt_flag &= ~MNT_ASYNC;
                  MNT_IUNLOCK(mp);
                  vfs_msync(mp, MNT_NOWAIT);
                  VFS_SYNC(mp, MNT_NOWAIT, td);
                  MNT_ILOCK(mp);
                  mp->mnt_flag |= asyncflag;
                  MNT_IUNLOCK(mp);
                  vn_finished_write(mp);
            }
            mtx_lock(&mountlist_mtx);
            nmp = TAILQ_NEXT(mp, mnt_list);
            vfs_unbusy(mp, td);
      }
      mtx_unlock(&mountlist_mtx);
#if 0
/*
 * XXX don't call vfs_bufstats() yet because that routine
 * was not imported in the Lite2 merge.
 */
#ifdef DIAGNOSTIC
      if (syncprt)
            vfs_bufstats();
#endif /* DIAGNOSTIC */
#endif
      mtx_unlock(&Giant);
      return (0);
}

/* XXX PRISON: could be per prison flag */
static int prison_quotas;
#if 0
SYSCTL_INT(_kern_prison, OID_AUTO, quotas, CTLFLAG_RW, &prison_quotas, 0, "");
#endif

/*
 * Change filesystem quotas.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct quotactl_args {
      char *path;
      int cmd;
      int uid;
      caddr_t arg;
};
#endif
int
quotactl(td, uap)
      struct thread *td;
      register struct quotactl_args /* {
            char *path;
            int cmd;
            int uid;
            caddr_t arg;
      } */ *uap;
{
      struct mount *mp, *vmp;
      int error;
      struct nameidata nd;

      AUDIT_ARG(cmd, uap->cmd);
      AUDIT_ARG(uid, uap->uid);
      if (jailed(td->td_ucred) && !prison_quotas)
            return (EPERM);
      mtx_lock(&Giant);
      NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, UIO_USERSPACE, uap->path, td);
      if ((error = namei(&nd)) != 0) {
            mtx_unlock(&Giant);
            return (error);
      }
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = vn_start_write(nd.ni_vp, &vmp, V_WAIT | PCATCH);
      mp = nd.ni_vp->v_mount;
      vrele(nd.ni_vp);
      if (error) {
            mtx_unlock(&Giant);
            return (error);
      }
      error = VFS_QUOTACTL(mp, uap->cmd, uap->uid, uap->arg, td);
      vn_finished_write(vmp);
      mtx_unlock(&Giant);
      return (error);
}

/*
 * Get filesystem statistics.
 */
#ifndef _SYS_SYSPROTO_H_
struct statfs_args {
      char *path;
      struct statfs *buf;
};
#endif
int
statfs(td, uap)
      struct thread *td;
      register struct statfs_args /* {
            char *path;
            struct statfs *buf;
      } */ *uap;
{
      struct statfs sf;
      int error;

      error = kern_statfs(td, uap->path, UIO_USERSPACE, &sf);
      if (error == 0)
            error = copyout(&sf, uap->buf, sizeof(sf));
      return (error);
}

int
kern_statfs(struct thread *td, char *path, enum uio_seg pathseg,
    struct statfs *buf)
{
      struct mount *mp;
      struct statfs *sp, sb;
      int error;
      struct nameidata nd;

      mtx_lock(&Giant);
      NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1 | LOCKLEAF, pathseg, path,
          td);
      error = namei(&nd);
      if (error) {
            mtx_unlock(&Giant);
            return (error);
      }
      mp = nd.ni_vp->v_mount;
      vfs_ref(mp);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_vp);
#ifdef MAC
      error = mac_check_mount_stat(td->td_ucred, mp);
      if (error)
            goto out;
#endif
      /*
       * Set these in case the underlying filesystem fails to do so.
       */
      sp = &mp->mnt_stat;
      sp->f_version = STATFS_VERSION;
      sp->f_namemax = NAME_MAX;
      sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
      error = VFS_STATFS(mp, sp, td);
      if (error)
            goto out;
      if (suser(td)) {
            bcopy(sp, &sb, sizeof(sb));
            sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
            prison_enforce_statfs(td->td_ucred, mp, &sb);
            sp = &sb;
      }
      *buf = *sp;
 out:
      vfs_rel(mp);
      mtx_unlock(&Giant);
      return (error);
}

/*
 * Get filesystem statistics.
 */
#ifndef _SYS_SYSPROTO_H_
struct fstatfs_args {
      int fd;
      struct statfs *buf;
};
#endif
int
fstatfs(td, uap)
      struct thread *td;
      register struct fstatfs_args /* {
            int fd;
            struct statfs *buf;
      } */ *uap;
{
      struct statfs sf;
      int error;

      error = kern_fstatfs(td, uap->fd, &sf);
      if (error == 0)
            error = copyout(&sf, uap->buf, sizeof(sf));
      return (error);
}

int
kern_fstatfs(struct thread *td, int fd, struct statfs *buf)
{
      struct file *fp;
      struct mount *mp;
      struct statfs *sp, sb;
      struct vnode *vp;
      int error;

      AUDIT_ARG(fd, fd);
      error = getvnode(td->td_proc->p_fd, fd, &fp);
      if (error)
            return (error);
      mtx_lock(&Giant);
      vp = fp->f_vnode;
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef AUDIT
      AUDIT_ARG(vnode, vp, ARG_VNODE1);
#endif
      mp = vp->v_mount;
      if (mp)
            vfs_ref(mp);
      VOP_UNLOCK(vp, 0, td);
      fdrop(fp, td);
      if (vp->v_iflag & VI_DOOMED) {
            if (mp)
                  vfs_rel(mp);
            mtx_unlock(&Giant);
            return (EBADF);
      }
#ifdef MAC
      error = mac_check_mount_stat(td->td_ucred, mp);
      if (error)
            goto out;
#endif
      /*
       * Set these in case the underlying filesystem fails to do so.
       */
      sp = &mp->mnt_stat;
      sp->f_version = STATFS_VERSION;
      sp->f_namemax = NAME_MAX;
      sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
      error = VFS_STATFS(mp, sp, td);
      if (error)
            goto out;
      if (suser(td)) {
            bcopy(sp, &sb, sizeof(sb));
            sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
            prison_enforce_statfs(td->td_ucred, mp, &sb);
            sp = &sb;
      }
      *buf = *sp;
out:
      vfs_rel(mp);
      mtx_unlock(&Giant);
      return (error);
}

/*
 * Get statistics on all filesystems.
 */
#ifndef _SYS_SYSPROTO_H_
struct getfsstat_args {
      struct statfs *buf;
      long bufsize;
      int flags;
};
#endif
int
getfsstat(td, uap)
      struct thread *td;
      register struct getfsstat_args /* {
            struct statfs *buf;
            long bufsize;
            int flags;
      } */ *uap;
{

      return (kern_getfsstat(td, &uap->buf, uap->bufsize, UIO_USERSPACE,
          uap->flags));
}

/*
 * If (bufsize > 0 && bufseg == UIO_SYSSPACE)
 *    The caller is responsible for freeing memory which will be allocated
 *    in '*buf'.
 */
int
kern_getfsstat(struct thread *td, struct statfs **buf, size_t bufsize,
    enum uio_seg bufseg, int flags)
{
      struct mount *mp, *nmp;
      struct statfs *sfsp, *sp, sb;
      size_t count, maxcount;
      int error;

      maxcount = bufsize / sizeof(struct statfs);
      if (bufsize == 0)
            sfsp = NULL;
      else if (bufseg == UIO_USERSPACE)
            sfsp = *buf;
      else /* if (bufseg == UIO_SYSSPACE) */ {
            count = 0;
            mtx_lock(&mountlist_mtx);
            TAILQ_FOREACH(mp, &mountlist, mnt_list) {
                  count++;
            }
            mtx_unlock(&mountlist_mtx);
            if (maxcount > count)
                  maxcount = count;
            sfsp = *buf = malloc(maxcount * sizeof(struct statfs), M_TEMP,
                M_WAITOK);
      }
      count = 0;
      mtx_lock(&Giant);
      mtx_lock(&mountlist_mtx);
      for (mp = TAILQ_FIRST(&mountlist); mp != NULL; mp = nmp) {
            if (prison_canseemount(td->td_ucred, mp) != 0) {
                  nmp = TAILQ_NEXT(mp, mnt_list);
                  continue;
            }
#ifdef MAC
            if (mac_check_mount_stat(td->td_ucred, mp) != 0) {
                  nmp = TAILQ_NEXT(mp, mnt_list);
                  continue;
            }
#endif
            if (vfs_busy(mp, LK_NOWAIT, &mountlist_mtx, td)) {
                  nmp = TAILQ_NEXT(mp, mnt_list);
                  continue;
            }
            if (sfsp && count < maxcount) {
                  sp = &mp->mnt_stat;
                  /*
                   * Set these in case the underlying filesystem
                   * fails to do so.
                   */
                  sp->f_version = STATFS_VERSION;
                  sp->f_namemax = NAME_MAX;
                  sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
                  /*
                   * If MNT_NOWAIT or MNT_LAZY is specified, do not
                   * refresh the fsstat cache. MNT_NOWAIT or MNT_LAZY
                   * overrides MNT_WAIT.
                   */
                  if (((flags & (MNT_LAZY|MNT_NOWAIT)) == 0 ||
                      (flags & MNT_WAIT)) &&
                      (error = VFS_STATFS(mp, sp, td))) {
                        mtx_lock(&mountlist_mtx);
                        nmp = TAILQ_NEXT(mp, mnt_list);
                        vfs_unbusy(mp, td);
                        continue;
                  }
                  if (suser(td)) {
                        bcopy(sp, &sb, sizeof(sb));
                        sb.f_fsid.val[0] = sb.f_fsid.val[1] = 0;
                        prison_enforce_statfs(td->td_ucred, mp, &sb);
                        sp = &sb;
                  }
                  if (bufseg == UIO_SYSSPACE)
                        bcopy(sp, sfsp, sizeof(*sp));
                  else /* if (bufseg == UIO_USERSPACE) */ {
                        error = copyout(sp, sfsp, sizeof(*sp));
                        if (error) {
                              vfs_unbusy(mp, td);
                              mtx_unlock(&Giant);
                              return (error);
                        }
                  }
                  sfsp++;
            }
            count++;
            mtx_lock(&mountlist_mtx);
            nmp = TAILQ_NEXT(mp, mnt_list);
            vfs_unbusy(mp, td);
      }
      mtx_unlock(&mountlist_mtx);
      mtx_unlock(&Giant);
      if (sfsp && count > maxcount)
            td->td_retval[0] = maxcount;
      else
            td->td_retval[0] = count;
      return (0);
}

#ifdef COMPAT_FREEBSD4
/*
 * Get old format filesystem statistics.
 */
static void cvtstatfs(struct statfs *, struct ostatfs *);

#ifndef _SYS_SYSPROTO_H_
struct freebsd4_statfs_args {
      char *path;
      struct ostatfs *buf;
};
#endif
int
freebsd4_statfs(td, uap)
      struct thread *td;
      struct freebsd4_statfs_args /* {
            char *path;
            struct ostatfs *buf;
      } */ *uap;
{
      struct ostatfs osb;
      struct statfs sf;
      int error;

      error = kern_statfs(td, uap->path, UIO_USERSPACE, &sf);
      if (error)
            return (error);
      cvtstatfs(&sf, &osb);
      return (copyout(&osb, uap->buf, sizeof(osb)));
}

/*
 * Get filesystem statistics.
 */
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_fstatfs_args {
      int fd;
      struct ostatfs *buf;
};
#endif
int
freebsd4_fstatfs(td, uap)
      struct thread *td;
      struct freebsd4_fstatfs_args /* {
            int fd;
            struct ostatfs *buf;
      } */ *uap;
{
      struct ostatfs osb;
      struct statfs sf;
      int error;

      error = kern_fstatfs(td, uap->fd, &sf);
      if (error)
            return (error);
      cvtstatfs(&sf, &osb);
      return (copyout(&osb, uap->buf, sizeof(osb)));
}

/*
 * Get statistics on all filesystems.
 */
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_getfsstat_args {
      struct ostatfs *buf;
      long bufsize;
      int flags;
};
#endif
int
freebsd4_getfsstat(td, uap)
      struct thread *td;
      register struct freebsd4_getfsstat_args /* {
            struct ostatfs *buf;
            long bufsize;
            int flags;
      } */ *uap;
{
      struct statfs *buf, *sp;
      struct ostatfs osb;
      size_t count, size;
      int error;

      count = uap->bufsize / sizeof(struct ostatfs);
      size = count * sizeof(struct statfs);
      error = kern_getfsstat(td, &buf, size, UIO_SYSSPACE, uap->flags);
      if (size > 0) {
            count = td->td_retval[0];
            sp = buf;
            while (count > 0 && error == 0) {
                  cvtstatfs(sp, &osb);
                  error = copyout(&osb, uap->buf, sizeof(osb));
                  sp++;
                  uap->buf++;
                  count--;
            }
            free(buf, M_TEMP);
      }
      return (error);
}

/*
 * Implement fstatfs() for (NFS) file handles.
 */
#ifndef _SYS_SYSPROTO_H_
struct freebsd4_fhstatfs_args {
      struct fhandle *u_fhp;
      struct ostatfs *buf;
};
#endif
int
freebsd4_fhstatfs(td, uap)
      struct thread *td;
      struct freebsd4_fhstatfs_args /* {
            struct fhandle *u_fhp;
            struct ostatfs *buf;
      } */ *uap;
{
      struct ostatfs osb;
      struct statfs sf;
      fhandle_t fh;
      int error;

      error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
      if (error)
            return (error);
      error = kern_fhstatfs(td, fh, &sf);
      if (error)
            return (error);
      cvtstatfs(&sf, &osb);
      return (copyout(&osb, uap->buf, sizeof(osb)));
}

/*
 * Convert a new format statfs structure to an old format statfs structure.
 */
static void
cvtstatfs(nsp, osp)
      struct statfs *nsp;
      struct ostatfs *osp;
{

      bzero(osp, sizeof(*osp));
      osp->f_bsize = MIN(nsp->f_bsize, LONG_MAX);
      osp->f_iosize = MIN(nsp->f_iosize, LONG_MAX);
      osp->f_blocks = MIN(nsp->f_blocks, LONG_MAX);
      osp->f_bfree = MIN(nsp->f_bfree, LONG_MAX);
      osp->f_bavail = MIN(nsp->f_bavail, LONG_MAX);
      osp->f_files = MIN(nsp->f_files, LONG_MAX);
      osp->f_ffree = MIN(nsp->f_ffree, LONG_MAX);
      osp->f_owner = nsp->f_owner;
      osp->f_type = nsp->f_type;
      osp->f_flags = nsp->f_flags;
      osp->f_syncwrites = MIN(nsp->f_syncwrites, LONG_MAX);
      osp->f_asyncwrites = MIN(nsp->f_asyncwrites, LONG_MAX);
      osp->f_syncreads = MIN(nsp->f_syncreads, LONG_MAX);
      osp->f_asyncreads = MIN(nsp->f_asyncreads, LONG_MAX);
      strlcpy(osp->f_fstypename, nsp->f_fstypename,
          MIN(MFSNAMELEN, OMFSNAMELEN));
      strlcpy(osp->f_mntonname, nsp->f_mntonname,
          MIN(MNAMELEN, OMNAMELEN));
      strlcpy(osp->f_mntfromname, nsp->f_mntfromname,
          MIN(MNAMELEN, OMNAMELEN));
      osp->f_fsid = nsp->f_fsid;
}
#endif /* COMPAT_FREEBSD4 */

/*
 * Change current working directory to a given file descriptor.
 */
#ifndef _SYS_SYSPROTO_H_
struct fchdir_args {
      int   fd;
};
#endif
int
fchdir(td, uap)
      struct thread *td;
      struct fchdir_args /* {
            int fd;
      } */ *uap;
{
      register struct filedesc *fdp = td->td_proc->p_fd;
      struct vnode *vp, *tdp, *vpold;
      struct mount *mp;
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, uap->fd);
      if ((error = getvnode(fdp, uap->fd, &fp)) != 0)
            return (error);
      vp = fp->f_vnode;
      vfslocked = VFS_LOCK_GIANT(vp->v_mount);
      VREF(vp);
      fdrop(fp, td);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, vp, ARG_VNODE1);
      if (vp->v_type != VDIR)
            error = ENOTDIR;
#ifdef MAC
      else if ((error = mac_check_vnode_chdir(td->td_ucred, vp)) != 0) {
      }
#endif
      else
            error = VOP_ACCESS(vp, VEXEC, td->td_ucred, td);
      while (!error && (mp = vp->v_mountedhere) != NULL) {
            int tvfslocked;
            if (vfs_busy(mp, 0, 0, td))
                  continue;
            tvfslocked = VFS_LOCK_GIANT(mp);
            error = VFS_ROOT(mp, LK_EXCLUSIVE, &tdp, td);
            vfs_unbusy(mp, td);
            if (error) {
                  VFS_UNLOCK_GIANT(tvfslocked);
                  break;
            }
            vput(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            vp = tdp;
            vfslocked = tvfslocked;
      }
      if (error) {
            vput(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (error);
      }
      VOP_UNLOCK(vp, 0, td);
      VFS_UNLOCK_GIANT(vfslocked);
      FILEDESC_LOCK_FAST(fdp);
      vpold = fdp->fd_cdir;
      fdp->fd_cdir = vp;
      FILEDESC_UNLOCK_FAST(fdp);
      vfslocked = VFS_LOCK_GIANT(vpold->v_mount);
      vrele(vpold);
      VFS_UNLOCK_GIANT(vfslocked);
      return (0);
}

/*
 * Change current working directory (``.'').
 */
#ifndef _SYS_SYSPROTO_H_
struct chdir_args {
      char  *path;
};
#endif
int
chdir(td, uap)
      struct thread *td;
      struct chdir_args /* {
            char *path;
      } */ *uap;
{

      return (kern_chdir(td, uap->path, UIO_USERSPACE));
}

int
kern_chdir(struct thread *td, char *path, enum uio_seg pathseg)
{
      register struct filedesc *fdp = td->td_proc->p_fd;
      int error;
      struct nameidata nd;
      struct vnode *vp;
      int vfslocked;

      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | AUDITVNODE1 | MPSAFE,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      if ((error = change_dir(nd.ni_vp, td)) != 0) {
            vput(nd.ni_vp);
            VFS_UNLOCK_GIANT(vfslocked);
            NDFREE(&nd, NDF_ONLY_PNBUF);
            return (error);
      }
      VOP_UNLOCK(nd.ni_vp, 0, td);
      VFS_UNLOCK_GIANT(vfslocked);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      FILEDESC_LOCK_FAST(fdp);
      vp = fdp->fd_cdir;
      fdp->fd_cdir = nd.ni_vp;
      FILEDESC_UNLOCK_FAST(fdp);
      vfslocked = VFS_LOCK_GIANT(vp->v_mount);
      vrele(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (0);
}

/*
 * Helper function for raised chroot(2) security function:  Refuse if
 * any filedescriptors are open directories.
 */
static int
chroot_refuse_vdir_fds(fdp)
      struct filedesc *fdp;
{
      struct vnode *vp;
      struct file *fp;
      int fd;

      FILEDESC_LOCK_ASSERT(fdp, MA_OWNED);
      for (fd = 0; fd < fdp->fd_nfiles ; fd++) {
            fp = fget_locked(fdp, fd);
            if (fp == NULL)
                  continue;
            if (fp->f_type == DTYPE_VNODE) {
                  vp = fp->f_vnode;
                  if (vp->v_type == VDIR)
                        return (EPERM);
            }
      }
      return (0);
}

/*
 * This sysctl determines if we will allow a process to chroot(2) if it
 * has a directory open:
 *    0: disallowed for all processes.
 *    1: allowed for processes that were not already chroot(2)'ed.
 *    2: allowed for all processes.
 */

static int chroot_allow_open_directories = 1;

SYSCTL_INT(_kern, OID_AUTO, chroot_allow_open_directories, CTLFLAG_RW,
     &chroot_allow_open_directories, 0, "");

/*
 * Change notion of root (``/'') directory.
 */
#ifndef _SYS_SYSPROTO_H_
struct chroot_args {
      char  *path;
};
#endif
int
chroot(td, uap)
      struct thread *td;
      struct chroot_args /* {
            char *path;
      } */ *uap;
{
      int error;
      struct nameidata nd;
      int vfslocked;

      error = suser_cred(td->td_ucred, SUSER_ALLOWJAIL);
      if (error)
            return (error);
      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          UIO_USERSPACE, uap->path, td);
      error = namei(&nd);
      if (error)
            goto error;
      vfslocked = NDHASGIANT(&nd);
      if ((error = change_dir(nd.ni_vp, td)) != 0)
            goto e_vunlock;
#ifdef MAC
      if ((error = mac_check_vnode_chroot(td->td_ucred, nd.ni_vp)))
            goto e_vunlock;
#endif
      VOP_UNLOCK(nd.ni_vp, 0, td);
      error = change_root(nd.ni_vp, td);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      return (error);
e_vunlock:
      vput(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
error:
      NDFREE(&nd, NDF_ONLY_PNBUF);
      return (error);
}

/*
 * Common routine for chroot and chdir.  Callers must provide a locked vnode
 * instance.
 */
int
change_dir(vp, td)
      struct vnode *vp;
      struct thread *td;
{
      int error;

      ASSERT_VOP_LOCKED(vp, "change_dir(): vp not locked");
      if (vp->v_type != VDIR)
            return (ENOTDIR);
#ifdef MAC
      error = mac_check_vnode_chdir(td->td_ucred, vp);
      if (error)
            return (error);
#endif
      error = VOP_ACCESS(vp, VEXEC, td->td_ucred, td);
      return (error);
}

/*
 * Common routine for kern_chroot() and jail_attach().  The caller is
 * responsible for invoking suser() and mac_check_chroot() to authorize this
 * operation.
 */
int
change_root(vp, td)
      struct vnode *vp;
      struct thread *td;
{
      struct filedesc *fdp;
      struct vnode *oldvp;
      int vfslocked;
      int error;

      VFS_ASSERT_GIANT(vp->v_mount);
      fdp = td->td_proc->p_fd;
      FILEDESC_LOCK(fdp);
      if (chroot_allow_open_directories == 0 ||
          (chroot_allow_open_directories == 1 && fdp->fd_rdir != rootvnode)) {
            error = chroot_refuse_vdir_fds(fdp);
            if (error) {
                  FILEDESC_UNLOCK(fdp);
                  return (error);
            }
      }
      oldvp = fdp->fd_rdir;
      fdp->fd_rdir = vp;
      VREF(fdp->fd_rdir);
      if (!fdp->fd_jdir) {
            fdp->fd_jdir = vp;
            VREF(fdp->fd_jdir);
      }
      FILEDESC_UNLOCK(fdp);
      vfslocked = VFS_LOCK_GIANT(oldvp->v_mount);
      vrele(oldvp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (0);
}

/*
 * Check permissions, allocate an open file structure,
 * and call the device open routine if any.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct open_args {
      char  *path;
      int   flags;
      int   mode;
};
#endif
int
open(td, uap)
      struct thread *td;
      register struct open_args /* {
            char *path;
            int flags;
            int mode;
      } */ *uap;
{
      int error;

      error = kern_open(td, uap->path, UIO_USERSPACE, uap->flags, uap->mode);
      if (mtx_owned(&Giant))
            printf("open: %s: %d\n", uap->path, error);
      return (error);
}

int
kern_open(struct thread *td, char *path, enum uio_seg pathseg, int flags,
    int mode)
{
      struct proc *p = td->td_proc;
      struct filedesc *fdp = p->p_fd;
      struct file *fp;
      struct vnode *vp;
      struct vattr vat;
      struct mount *mp;
      int cmode;
      struct file *nfp;
      int type, indx, error;
      struct flock lf;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(fflags, flags);
      AUDIT_ARG(mode, mode);
      if ((flags & O_ACCMODE) == O_ACCMODE)
            return (EINVAL);
      flags = FFLAGS(flags);
      error = falloc(td, &nfp, &indx);
      if (error)
            return (error);
      /* An extra reference on `nfp' has been held for us by falloc(). */
      fp = nfp;
      cmode = ((mode &~ fdp->fd_cmask) & ALLPERMS) &~ S_ISTXT;
      NDINIT(&nd, LOOKUP, FOLLOW | AUDITVNODE1, pathseg, path, td);
      td->td_dupfd = -1;            /* XXX check for fdopen */
      FILEDESC_LOCK(fdp);
      if (fp != fdp->fd_ofiles[indx]) {
            FILEDESC_UNLOCK(fdp);
            fdrop(fp, td);
            td->td_retval[0] = indx;
            return (0);
      }
      fdp->fd_ofileflags[indx] |= UF_OPENING;
      FILEDESC_UNLOCK(fdp);
      error = vn_open(&nd, &flags, cmode, indx);
      FILEDESC_LOCK(fdp);
      fdp->fd_ofileflags[indx] &= ~UF_OPENING;
      FILEDESC_UNLOCK(fdp);
      if (error) {
            /*
             * If the vn_open replaced the method vector, something
             * wonderous happened deep below and we just pass it up
             * pretending we know what we do.
             */
            if (error == ENXIO && fp->f_ops != &badfileops) {
                  fdrop(fp, td);
                  td->td_retval[0] = indx;
                  return (0);
            }

            /*
             * handle special fdopen() case.  bleh.  dupfdopen() is
             * responsible for dropping the old contents of ofiles[indx]
             * if it succeeds.
             */
            if ((error == ENODEV || error == ENXIO) &&
                td->td_dupfd >= 0 &&            /* XXX from fdopen */
                (error =
                  dupfdopen(td, fdp, indx, td->td_dupfd, flags, error)) == 0) {
                  td->td_retval[0] = indx;
                  fdrop(fp, td);
                  return (0);
            }
            /*
             * Clean up the descriptor, but only if another thread hadn't
             * replaced or closed it.
             */
            fdclose(fdp, fp, indx, td);
            fdrop(fp, td);

            if (error == ERESTART)
                  error = EINTR;
            return (error);
      }
      td->td_dupfd = 0;
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vp = nd.ni_vp;

      FILEDESC_LOCK_FAST(fdp);
      FILE_LOCK(fp);
      fp->f_vnode = vp;
      if (fp->f_data == NULL)
            fp->f_data = vp;
      fp->f_flag = flags & FMASK;
      if (fp->f_ops == &badfileops)
            fp->f_ops = &vnops;
      fp->f_seqcount = 1;
      fp->f_type = (vp->v_type == VFIFO ? DTYPE_FIFO : DTYPE_VNODE);
      FILE_UNLOCK(fp);
      FILEDESC_UNLOCK_FAST(fdp);

      VOP_UNLOCK(vp, 0, td);
      if (flags & (O_EXLOCK | O_SHLOCK)) {
            lf.l_whence = SEEK_SET;
            lf.l_start = 0;
            lf.l_len = 0;
            if (flags & O_EXLOCK)
                  lf.l_type = F_WRLCK;
            else
                  lf.l_type = F_RDLCK;
            type = F_FLOCK;
            if ((flags & FNONBLOCK) == 0)
                  type |= F_WAIT;
            if ((error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
                      type)) != 0)
                  goto bad;
            fp->f_flag |= FHASLOCK;
      }
      if (flags & O_TRUNC) {
            if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
                  goto bad;
            VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
            VATTR_NULL(&vat);
            vat.va_size = 0;
            vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
#ifdef MAC
            error = mac_check_vnode_write(td->td_ucred, fp->f_cred, vp);
            if (error == 0)
#endif
                  error = VOP_SETATTR(vp, &vat, td->td_ucred, td);
            VOP_UNLOCK(vp, 0, td);
            vn_finished_write(mp);
            if (error)
                  goto bad;
      }
      VFS_UNLOCK_GIANT(vfslocked);
      /*
       * Release our private reference, leaving the one associated with
       * the descriptor table intact.
       */
      fdrop(fp, td);
      td->td_retval[0] = indx;
      return (0);
bad:
      VFS_UNLOCK_GIANT(vfslocked);
      fdclose(fdp, fp, indx, td);
      fdrop(fp, td);
      return (error);
}

#ifdef COMPAT_43
/*
 * Create a file.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct ocreat_args {
      char  *path;
      int   mode;
};
#endif
int
ocreat(td, uap)
      struct thread *td;
      register struct ocreat_args /* {
            char *path;
            int mode;
      } */ *uap;
{

      return (kern_open(td, uap->path, UIO_USERSPACE,
          O_WRONLY | O_CREAT | O_TRUNC, uap->mode));
}
#endif /* COMPAT_43 */

/*
 * Create a special file.
 */
#ifndef _SYS_SYSPROTO_H_
struct mknod_args {
      char  *path;
      int   mode;
      int   dev;
};
#endif
int
mknod(td, uap)
      struct thread *td;
      register struct mknod_args /* {
            char *path;
            int mode;
            int dev;
      } */ *uap;
{

      return (kern_mknod(td, uap->path, UIO_USERSPACE, uap->mode, uap->dev));
}

int
kern_mknod(struct thread *td, char *path, enum uio_seg pathseg, int mode,
    int dev)
{
      struct vnode *vp;
      struct mount *mp;
      struct vattr vattr;
      int error;
      int whiteout = 0;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(mode, mode);
      AUDIT_ARG(dev, dev);
      switch (mode & S_IFMT) {
      case S_IFCHR:
      case S_IFBLK:
            error = suser(td);
            break;
      default:
            error = suser_cred(td->td_ucred, SUSER_ALLOWJAIL);
            break;
      }
      if (error)
            return (error);
restart:
      bwillwrite();
      NDINIT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      if (vp != NULL) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            if (vp == nd.ni_dvp)
                  vrele(nd.ni_dvp);
            else
                  vput(nd.ni_dvp);
            vrele(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (EEXIST);
      } else {
            VATTR_NULL(&vattr);
            FILEDESC_LOCK_FAST(td->td_proc->p_fd);
            vattr.va_mode = (mode & ALLPERMS) &
                ~td->td_proc->p_fd->fd_cmask;
            FILEDESC_UNLOCK_FAST(td->td_proc->p_fd);
            vattr.va_rdev = dev;
            whiteout = 0;

            switch (mode & S_IFMT) {
            case S_IFMT:      /* used by badsect to flag bad sectors */
                  vattr.va_type = VBAD;
                  break;
            case S_IFCHR:
                  vattr.va_type = VCHR;
                  break;
            case S_IFBLK:
                  vattr.va_type = VBLK;
                  break;
            case S_IFWHT:
                  whiteout = 1;
                  break;
            default:
                  error = EINVAL;
                  break;
            }
      }
      if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            vput(nd.ni_dvp);
            VFS_UNLOCK_GIANT(vfslocked);
            if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
                  return (error);
            goto restart;
      }
#ifdef MAC
      if (error == 0 && !whiteout)
            error = mac_check_vnode_create(td->td_ucred, nd.ni_dvp,
                &nd.ni_cnd, &vattr);
#endif
      if (!error) {
            VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
            if (whiteout)
                  error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, CREATE);
            else {
                  error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp,
                                    &nd.ni_cnd, &vattr);
                  if (error == 0)
                        vput(nd.ni_vp);
            }
      }
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_dvp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Create a named pipe.
 */
#ifndef _SYS_SYSPROTO_H_
struct mkfifo_args {
      char  *path;
      int   mode;
};
#endif
int
mkfifo(td, uap)
      struct thread *td;
      register struct mkfifo_args /* {
            char *path;
            int mode;
      } */ *uap;
{

      return (kern_mkfifo(td, uap->path, UIO_USERSPACE, uap->mode));
}

int
kern_mkfifo(struct thread *td, char *path, enum uio_seg pathseg, int mode)
{
      struct mount *mp;
      struct vattr vattr;
      int error;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(mode, mode);
restart:
      bwillwrite();
      NDINIT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      if (nd.ni_vp != NULL) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            if (nd.ni_vp == nd.ni_dvp)
                  vrele(nd.ni_dvp);
            else
                  vput(nd.ni_dvp);
            vrele(nd.ni_vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (EEXIST);
      }
      if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            vput(nd.ni_dvp);
            VFS_UNLOCK_GIANT(vfslocked);
            if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
                  return (error);
            goto restart;
      }
      VATTR_NULL(&vattr);
      vattr.va_type = VFIFO;
      FILEDESC_LOCK_FAST(td->td_proc->p_fd);
      vattr.va_mode = (mode & ALLPERMS) & ~td->td_proc->p_fd->fd_cmask;
      FILEDESC_UNLOCK_FAST(td->td_proc->p_fd);
#ifdef MAC
      error = mac_check_vnode_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
          &vattr);
      if (error)
            goto out;
#endif
      VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
      error = VOP_MKNOD(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
      if (error == 0)
            vput(nd.ni_vp);
#ifdef MAC
out:
#endif
      vput(nd.ni_dvp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      return (error);
}

/*
 * Make a hard file link.
 */
#ifndef _SYS_SYSPROTO_H_
struct link_args {
      char  *path;
      char  *link;
};
#endif
int
link(td, uap)
      struct thread *td;
      register struct link_args /* {
            char *path;
            char *link;
      } */ *uap;
{
      int error;

      error = kern_link(td, uap->path, uap->link, UIO_USERSPACE);
      return (error);
}

SYSCTL_DECL(_security_bsd);

static int hardlink_check_uid = 0;
SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_uid, CTLFLAG_RW,
    &hardlink_check_uid, 0,
    "Unprivileged processes cannot create hard links to files owned by other "
    "users");
static int hardlink_check_gid = 0;
SYSCTL_INT(_security_bsd, OID_AUTO, hardlink_check_gid, CTLFLAG_RW,
    &hardlink_check_gid, 0,
    "Unprivileged processes cannot create hard links to files owned by other "
    "groups");

static int
can_hardlink(struct vnode *vp, struct thread *td, struct ucred *cred)
{
      struct vattr va;
      int error;

      if (suser_cred(cred, SUSER_ALLOWJAIL) == 0)
            return (0);

      if (!hardlink_check_uid && !hardlink_check_gid)
            return (0);

      error = VOP_GETATTR(vp, &va, cred, td);
      if (error != 0)
            return (error);

      if (hardlink_check_uid) {
            if (cred->cr_uid != va.va_uid)
                  return (EPERM);
      }

      if (hardlink_check_gid) {
            if (!groupmember(va.va_gid, cred))
                  return (EPERM);
      }

      return (0);
}

int
kern_link(struct thread *td, char *path, char *link, enum uio_seg segflg)
{
      struct vnode *vp;
      struct mount *mp;
      struct nameidata nd;
      int vfslocked;
      int lvfslocked;
      int error;

      bwillwrite();
      NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, segflg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vp = nd.ni_vp;
      if (vp->v_type == VDIR) {
            vrele(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (EPERM);         /* POSIX */
      }
      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
            vrele(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (error);
      }
      NDINIT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE2,
          segflg, link, td);
      if ((error = namei(&nd)) == 0) {
            lvfslocked = NDHASGIANT(&nd);
            if (nd.ni_vp != NULL) {
                  if (nd.ni_dvp == nd.ni_vp)
                        vrele(nd.ni_dvp);
                  else
                        vput(nd.ni_dvp);
                  vrele(nd.ni_vp);
                  error = EEXIST;
            } else if ((error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td))
                == 0) {
                  VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
                  VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
                  error = can_hardlink(vp, td, td->td_ucred);
                  if (error == 0)
#ifdef MAC
                        error = mac_check_vnode_link(td->td_ucred,
                            nd.ni_dvp, vp, &nd.ni_cnd);
                  if (error == 0)
#endif
                        error = VOP_LINK(nd.ni_dvp, vp, &nd.ni_cnd);
                  VOP_UNLOCK(vp, 0, td);
                  vput(nd.ni_dvp);
            }
            NDFREE(&nd, NDF_ONLY_PNBUF);
            VFS_UNLOCK_GIANT(lvfslocked);
      }
      vrele(vp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Make a symbolic link.
 */
#ifndef _SYS_SYSPROTO_H_
struct symlink_args {
      char  *path;
      char  *link;
};
#endif
int
symlink(td, uap)
      struct thread *td;
      register struct symlink_args /* {
            char *path;
            char *link;
      } */ *uap;
{

      return (kern_symlink(td, uap->path, uap->link, UIO_USERSPACE));
}

int
kern_symlink(struct thread *td, char *path, char *link, enum uio_seg segflg)
{
      struct mount *mp;
      struct vattr vattr;
      char *syspath;
      int error;
      struct nameidata nd;
      int vfslocked;

      if (segflg == UIO_SYSSPACE) {
            syspath = path;
      } else {
            syspath = uma_zalloc(namei_zone, M_WAITOK);
            if ((error = copyinstr(path, syspath, MAXPATHLEN, NULL)) != 0)
                  goto out;
      }
      AUDIT_ARG(text, syspath);
restart:
      bwillwrite();
      NDINIT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1,
          segflg, link, td);
      if ((error = namei(&nd)) != 0)
            goto out;
      vfslocked = NDHASGIANT(&nd);
      if (nd.ni_vp) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            if (nd.ni_vp == nd.ni_dvp)
                  vrele(nd.ni_dvp);
            else
                  vput(nd.ni_dvp);
            vrele(nd.ni_vp);
            VFS_UNLOCK_GIANT(vfslocked);
            error = EEXIST;
            goto out;
      }
      if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            vput(nd.ni_dvp);
            VFS_UNLOCK_GIANT(vfslocked);
            if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
                  goto out;
            goto restart;
      }
      VATTR_NULL(&vattr);
      FILEDESC_LOCK_FAST(td->td_proc->p_fd);
      vattr.va_mode = ACCESSPERMS &~ td->td_proc->p_fd->fd_cmask;
      FILEDESC_UNLOCK_FAST(td->td_proc->p_fd);
#ifdef MAC
      vattr.va_type = VLNK;
      error = mac_check_vnode_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
          &vattr);
      if (error)
            goto out2;
#endif
      VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
      error = VOP_SYMLINK(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr, syspath);
      if (error == 0)
            vput(nd.ni_vp);
#ifdef MAC
out2:
#endif
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_dvp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
out:
      if (segflg != UIO_SYSSPACE)
            uma_zfree(namei_zone, syspath);
      return (error);
}

/*
 * Delete a whiteout from the filesystem.
 */
int
undelete(td, uap)
      struct thread *td;
      register struct undelete_args /* {
            char *path;
      } */ *uap;
{
      int error;
      struct mount *mp;
      struct nameidata nd;
      int vfslocked;

restart:
      bwillwrite();
      NDINIT(&nd, DELETE, LOCKPARENT | DOWHITEOUT | MPSAFE | AUDITVNODE1,
          UIO_USERSPACE, uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      vfslocked = NDHASGIANT(&nd);

      if (nd.ni_vp != NULLVP || !(nd.ni_cnd.cn_flags & ISWHITEOUT)) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            if (nd.ni_vp == nd.ni_dvp)
                  vrele(nd.ni_dvp);
            else
                  vput(nd.ni_dvp);
            if (nd.ni_vp)
                  vrele(nd.ni_vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (EEXIST);
      }
      if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            vput(nd.ni_dvp);
            VFS_UNLOCK_GIANT(vfslocked);
            if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
                  return (error);
            goto restart;
      }
      VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
      error = VOP_WHITEOUT(nd.ni_dvp, &nd.ni_cnd, DELETE);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_dvp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Delete a name from the filesystem.
 */
#ifndef _SYS_SYSPROTO_H_
struct unlink_args {
      char  *path;
};
#endif
int
unlink(td, uap)
      struct thread *td;
      struct unlink_args /* {
            char *path;
      } */ *uap;
{
      int error;

      error = kern_unlink(td, uap->path, UIO_USERSPACE);
      return (error);
}

int
kern_unlink(struct thread *td, char *path, enum uio_seg pathseg)
{
      struct mount *mp;
      struct vnode *vp;
      int error;
      struct nameidata nd;
      int vfslocked;

restart:
      bwillwrite();
      NDINIT(&nd, DELETE, LOCKPARENT | LOCKLEAF | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error == EINVAL ? EPERM : error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      if (vp->v_type == VDIR)
            error = EPERM;          /* POSIX */
      else {
            /*
             * The root of a mounted filesystem cannot be deleted.
             *
             * XXX: can this only be a VDIR case?
             */
            if (vp->v_vflag & VV_ROOT)
                  error = EBUSY;
      }
      if (error == 0) {
            if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
                  NDFREE(&nd, NDF_ONLY_PNBUF);
                  vput(nd.ni_dvp);
                  if (vp == nd.ni_dvp)
                        vrele(vp);
                  else
                        vput(vp);
                  VFS_UNLOCK_GIANT(vfslocked);
                  if ((error = vn_start_write(NULL, &mp,
                      V_XSLEEP | PCATCH)) != 0)
                        return (error);
                  goto restart;
            }
#ifdef MAC
            error = mac_check_vnode_delete(td->td_ucred, nd.ni_dvp, vp,
                &nd.ni_cnd);
            if (error)
                  goto out;
#endif
            VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
            error = VOP_REMOVE(nd.ni_dvp, vp, &nd.ni_cnd);
#ifdef MAC
out:
#endif
            vn_finished_write(mp);
      }
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_dvp);
      if (vp == nd.ni_dvp)
            vrele(vp);
      else
            vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Reposition read/write file offset.
 */
#ifndef _SYS_SYSPROTO_H_
struct lseek_args {
      int   fd;
      int   pad;
      off_t offset;
      int   whence;
};
#endif
int
lseek(td, uap)
      struct thread *td;
      register struct lseek_args /* {
            int fd;
            int pad;
            off_t offset;
            int whence;
      } */ *uap;
{
      struct ucred *cred = td->td_ucred;
      struct file *fp;
      struct vnode *vp;
      struct vattr vattr;
      off_t offset;
      int error, noneg;
      int vfslocked;

      if ((error = fget(td, uap->fd, &fp)) != 0)
            return (error);
      if (!(fp->f_ops->fo_flags & DFLAG_SEEKABLE)) {
            fdrop(fp, td);
            return (ESPIPE);
      }
      vp = fp->f_vnode;
      vfslocked = VFS_LOCK_GIANT(vp->v_mount);
      noneg = (vp->v_type != VCHR);
      offset = uap->offset;
      switch (uap->whence) {
      case L_INCR:
            if (noneg &&
                (fp->f_offset < 0 ||
                (offset > 0 && fp->f_offset > OFF_MAX - offset))) {
                  error = EOVERFLOW;
                  break;
            }
            offset += fp->f_offset;
            break;
      case L_XTND:
            vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
            error = VOP_GETATTR(vp, &vattr, cred, td);
            VOP_UNLOCK(vp, 0, td);
            if (error)
                  break;
            if (noneg &&
                (vattr.va_size > OFF_MAX ||
                (offset > 0 && vattr.va_size > OFF_MAX - offset))) {
                  error = EOVERFLOW;
                  break;
            }
            offset += vattr.va_size;
            break;
      case L_SET:
            break;
      default:
            error = EINVAL;
      }
      if (error == 0 && noneg && offset < 0)
            error = EINVAL;
      if (error != 0)
            goto drop;
      fp->f_offset = offset;
      *(off_t *)(td->td_retval) = fp->f_offset;
drop:
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

#if defined(COMPAT_43)
/*
 * Reposition read/write file offset.
 */
#ifndef _SYS_SYSPROTO_H_
struct olseek_args {
      int   fd;
      long  offset;
      int   whence;
};
#endif
int
olseek(td, uap)
      struct thread *td;
      register struct olseek_args /* {
            int fd;
            long offset;
            int whence;
      } */ *uap;
{
      struct lseek_args /* {
            int fd;
            int pad;
            off_t offset;
            int whence;
      } */ nuap;
      int error;

      nuap.fd = uap->fd;
      nuap.offset = uap->offset;
      nuap.whence = uap->whence;
      error = lseek(td, &nuap);
      return (error);
}
#endif /* COMPAT_43 */

/*
 * Check access permissions using passed credentials.
 */
static int
vn_access(vp, user_flags, cred, td)
      struct vnode      *vp;
      int         user_flags;
      struct ucred      *cred;
      struct thread     *td;
{
      int error, flags;

      /* Flags == 0 means only check for existence. */
      error = 0;
      if (user_flags) {
            flags = 0;
            if (user_flags & R_OK)
                  flags |= VREAD;
            if (user_flags & W_OK)
                  flags |= VWRITE;
            if (user_flags & X_OK)
                  flags |= VEXEC;
#ifdef MAC
            error = mac_check_vnode_access(cred, vp, flags);
            if (error)
                  return (error);
#endif
            if ((flags & VWRITE) == 0 || (error = vn_writechk(vp)) == 0)
                  error = VOP_ACCESS(vp, flags, cred, td);
      }
      return (error);
}

/*
 * Check access permissions using "real" credentials.
 */
#ifndef _SYS_SYSPROTO_H_
struct access_args {
      char  *path;
      int   flags;
};
#endif
int
access(td, uap)
      struct thread *td;
      register struct access_args /* {
            char *path;
            int flags;
      } */ *uap;
{

      return (kern_access(td, uap->path, UIO_USERSPACE, uap->flags));
}

int
kern_access(struct thread *td, char *path, enum uio_seg pathseg, int flags)
{
      struct ucred *cred, *tmpcred;
      register struct vnode *vp;
      struct nameidata nd;
      int vfslocked;
      int error;

      /*
       * Create and modify a temporary credential instead of one that
       * is potentially shared.  This could also mess up socket
       * buffer accounting which can run in an interrupt context.
       */
      cred = td->td_ucred;
      tmpcred = crdup(cred);
      tmpcred->cr_uid = cred->cr_ruid;
      tmpcred->cr_groups[0] = cred->cr_rgid;
      td->td_ucred = tmpcred;
      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            goto out1;
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;

      error = vn_access(vp, flags, tmpcred, td);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
out1:
      td->td_ucred = cred;
      crfree(tmpcred);
      return (error);
}

/*
 * Check access permissions using "effective" credentials.
 */
#ifndef _SYS_SYSPROTO_H_
struct eaccess_args {
      char  *path;
      int   flags;
};
#endif
int
eaccess(td, uap)
      struct thread *td;
      register struct eaccess_args /* {
            char *path;
            int flags;
      } */ *uap;
{
      struct nameidata nd;
      struct vnode *vp;
      int vfslocked;
      int error;

      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          UIO_USERSPACE, uap->path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vp = nd.ni_vp;
      vfslocked = NDHASGIANT(&nd);
      error = vn_access(vp, uap->flags, td->td_ucred, td);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

#if defined(COMPAT_43)
/*
 * Get file status; this version follows links.
 */
#ifndef _SYS_SYSPROTO_H_
struct ostat_args {
      char  *path;
      struct ostat *ub;
};
#endif
int
ostat(td, uap)
      struct thread *td;
      register struct ostat_args /* {
            char *path;
            struct ostat *ub;
      } */ *uap;
{
      struct stat sb;
      struct ostat osb;
      int error;

      error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
      if (error)
            return (error);
      cvtstat(&sb, &osb);
      error = copyout(&osb, uap->ub, sizeof (osb));
      return (error);
}

/*
 * Get file status; this version does not follow links.
 */
#ifndef _SYS_SYSPROTO_H_
struct olstat_args {
      char  *path;
      struct ostat *ub;
};
#endif
int
olstat(td, uap)
      struct thread *td;
      register struct olstat_args /* {
            char *path;
            struct ostat *ub;
      } */ *uap;
{
      struct stat sb;
      struct ostat osb;
      int error;

      error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
      if (error)
            return (error);
      cvtstat(&sb, &osb);
      error = copyout(&osb, uap->ub, sizeof (osb));
      return (error);
}

/*
 * Convert from an old to a new stat structure.
 */
void
cvtstat(st, ost)
      struct stat *st;
      struct ostat *ost;
{

      ost->st_dev = st->st_dev;
      ost->st_ino = st->st_ino;
      ost->st_mode = st->st_mode;
      ost->st_nlink = st->st_nlink;
      ost->st_uid = st->st_uid;
      ost->st_gid = st->st_gid;
      ost->st_rdev = st->st_rdev;
      if (st->st_size < (quad_t)1 << 32)
            ost->st_size = st->st_size;
      else
            ost->st_size = -2;
      ost->st_atime = st->st_atime;
      ost->st_mtime = st->st_mtime;
      ost->st_ctime = st->st_ctime;
      ost->st_blksize = st->st_blksize;
      ost->st_blocks = st->st_blocks;
      ost->st_flags = st->st_flags;
      ost->st_gen = st->st_gen;
}
#endif /* COMPAT_43 */

/*
 * Get file status; this version follows links.
 */
#ifndef _SYS_SYSPROTO_H_
struct stat_args {
      char  *path;
      struct stat *ub;
};
#endif
int
stat(td, uap)
      struct thread *td;
      register struct stat_args /* {
            char *path;
            struct stat *ub;
      } */ *uap;
{
      struct stat sb;
      int error;

      error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
      if (error == 0)
            error = copyout(&sb, uap->ub, sizeof (sb));
      return (error);
}

int
kern_stat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
{
      struct nameidata nd;
      struct stat sb;
      int error, vfslocked;

      NDINIT(&nd, LOOKUP,
          FOLLOW | LOCKSHARED | LOCKLEAF | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      error = vn_stat(nd.ni_vp, &sb, td->td_ucred, NOCRED, td);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      if (error)
            return (error);
      *sbp = sb;
      return (0);
}

/*
 * Get file status; this version does not follow links.
 */
#ifndef _SYS_SYSPROTO_H_
struct lstat_args {
      char  *path;
      struct stat *ub;
};
#endif
int
lstat(td, uap)
      struct thread *td;
      register struct lstat_args /* {
            char *path;
            struct stat *ub;
      } */ *uap;
{
      struct stat sb;
      int error;

      error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
      if (error == 0)
            error = copyout(&sb, uap->ub, sizeof (sb));
      return (error);
}

int
kern_lstat(struct thread *td, char *path, enum uio_seg pathseg, struct stat *sbp)
{
      struct vnode *vp;
      struct stat sb;
      struct nameidata nd;
      int error, vfslocked;

      NDINIT(&nd, LOOKUP,
          NOFOLLOW | LOCKLEAF | LOCKSHARED | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      if (error)
            return (error);
      *sbp = sb;
      return (0);
}

/*
 * Implementation of the NetBSD [l]stat() functions.
 */
void
cvtnstat(sb, nsb)
      struct stat *sb;
      struct nstat *nsb;
{
      bzero(nsb, sizeof *nsb);
      nsb->st_dev = sb->st_dev;
      nsb->st_ino = sb->st_ino;
      nsb->st_mode = sb->st_mode;
      nsb->st_nlink = sb->st_nlink;
      nsb->st_uid = sb->st_uid;
      nsb->st_gid = sb->st_gid;
      nsb->st_rdev = sb->st_rdev;
      nsb->st_atimespec = sb->st_atimespec;
      nsb->st_mtimespec = sb->st_mtimespec;
      nsb->st_ctimespec = sb->st_ctimespec;
      nsb->st_size = sb->st_size;
      nsb->st_blocks = sb->st_blocks;
      nsb->st_blksize = sb->st_blksize;
      nsb->st_flags = sb->st_flags;
      nsb->st_gen = sb->st_gen;
      nsb->st_birthtimespec = sb->st_birthtimespec;
}

#ifndef _SYS_SYSPROTO_H_
struct nstat_args {
      char  *path;
      struct nstat *ub;
};
#endif
int
nstat(td, uap)
      struct thread *td;
      register struct nstat_args /* {
            char *path;
            struct nstat *ub;
      } */ *uap;
{
      struct stat sb;
      struct nstat nsb;
      int error;

      error = kern_stat(td, uap->path, UIO_USERSPACE, &sb);
      if (error)
            return (error);
      cvtnstat(&sb, &nsb);
      error = copyout(&nsb, uap->ub, sizeof (nsb));
      return (error);
}

/*
 * NetBSD lstat.  Get file status; this version does not follow links.
 */
#ifndef _SYS_SYSPROTO_H_
struct lstat_args {
      char  *path;
      struct stat *ub;
};
#endif
int
nlstat(td, uap)
      struct thread *td;
      register struct nlstat_args /* {
            char *path;
            struct nstat *ub;
      } */ *uap;
{
      struct stat sb;
      struct nstat nsb;
      int error;

      error = kern_lstat(td, uap->path, UIO_USERSPACE, &sb);
      if (error)
            return (error);
      cvtnstat(&sb, &nsb);
      error = copyout(&nsb, uap->ub, sizeof (nsb));
      return (error);
}

/*
 * Get configurable pathname variables.
 */
#ifndef _SYS_SYSPROTO_H_
struct pathconf_args {
      char  *path;
      int   name;
};
#endif
int
pathconf(td, uap)
      struct thread *td;
      register struct pathconf_args /* {
            char *path;
            int name;
      } */ *uap;
{

      return (kern_pathconf(td, uap->path, UIO_USERSPACE, uap->name));
}

int
kern_pathconf(struct thread *td, char *path, enum uio_seg pathseg, int name)
{
      struct nameidata nd;
      int error, vfslocked;

      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      /* If asynchronous I/O is available, it works for all files. */
      if (name == _PC_ASYNC_IO)
            td->td_retval[0] = async_io_version;
      else
            error = VOP_PATHCONF(nd.ni_vp, name, td->td_retval);
      vput(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Return target name of a symbolic link.
 */
#ifndef _SYS_SYSPROTO_H_
struct readlink_args {
      char  *path;
      char  *buf;
      int   count;
};
#endif
int
readlink(td, uap)
      struct thread *td;
      register struct readlink_args /* {
            char *path;
            char *buf;
            int count;
      } */ *uap;
{

      return (kern_readlink(td, uap->path, UIO_USERSPACE, uap->buf,
          UIO_USERSPACE, uap->count));
}

int
kern_readlink(struct thread *td, char *path, enum uio_seg pathseg, char *buf,
    enum uio_seg bufseg, int count)
{
      register struct vnode *vp;
      struct iovec aiov;
      struct uio auio;
      int error;
      struct nameidata nd;
      int vfslocked;

      NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
#ifdef MAC
      error = mac_check_vnode_readlink(td->td_ucred, vp);
      if (error) {
            vput(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (error);
      }
#endif
      if (vp->v_type != VLNK)
            error = EINVAL;
      else {
            aiov.iov_base = buf;
            aiov.iov_len = count;
            auio.uio_iov = &aiov;
            auio.uio_iovcnt = 1;
            auio.uio_offset = 0;
            auio.uio_rw = UIO_READ;
            auio.uio_segflg = bufseg;
            auio.uio_td = td;
            auio.uio_resid = count;
            error = VOP_READLINK(vp, &auio, td->td_ucred);
      }
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      td->td_retval[0] = count - auio.uio_resid;
      return (error);
}

/*
 * Common implementation code for chflags() and fchflags().
 */
static int
setfflags(td, vp, flags)
      struct thread *td;
      struct vnode *vp;
      int flags;
{
      int error;
      struct mount *mp;
      struct vattr vattr;

      /*
       * Prevent non-root users from setting flags on devices.  When
       * a device is reused, users can retain ownership of the device
       * if they are allowed to set flags and programs assume that
       * chown can't fail when done as root.
       */
      if (vp->v_type == VCHR || vp->v_type == VBLK) {
            error = suser_cred(td->td_ucred, SUSER_ALLOWJAIL);
            if (error)
                  return (error);
      }

      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
            return (error);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      VATTR_NULL(&vattr);
      vattr.va_flags = flags;
#ifdef MAC
      error = mac_check_vnode_setflags(td->td_ucred, vp, vattr.va_flags);
      if (error == 0)
#endif
            error = VOP_SETATTR(vp, &vattr, td->td_ucred, td);
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
      return (error);
}

/*
 * Change flags of a file given a path name.
 */
#ifndef _SYS_SYSPROTO_H_
struct chflags_args {
      char  *path;
      int   flags;
};
#endif
int
chflags(td, uap)
      struct thread *td;
      register struct chflags_args /* {
            char *path;
            int flags;
      } */ *uap;
{
      int error;
      struct nameidata nd;
      int vfslocked;

      NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vfslocked = NDHASGIANT(&nd);
      error = setfflags(td, nd.ni_vp, uap->flags);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Same as chflags() but doesn't follow symlinks.
 */
int
lchflags(td, uap)
      struct thread *td;
      register struct lchflags_args /* {
            char *path;
            int flags;
      } */ *uap;
{
      int error;
      struct nameidata nd;
      int vfslocked;

      NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE, UIO_USERSPACE | AUDITVNODE1,
          uap->path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setfflags(td, nd.ni_vp, uap->flags);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Change flags of a file given a file descriptor.
 */
#ifndef _SYS_SYSPROTO_H_
struct fchflags_args {
      int   fd;
      int   flags;
};
#endif
int
fchflags(td, uap)
      struct thread *td;
      register struct fchflags_args /* {
            int fd;
            int flags;
      } */ *uap;
{
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(fflags, uap->flags);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
#ifdef AUDIT
      vn_lock(fp->f_vnode, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, fp->f_vnode, ARG_VNODE1);
      VOP_UNLOCK(fp->f_vnode, 0, td);
#endif
      error = setfflags(td, fp->f_vnode, uap->flags);
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Common implementation code for chmod(), lchmod() and fchmod().
 */
static int
setfmode(td, vp, mode)
      struct thread *td;
      struct vnode *vp;
      int mode;
{
      int error;
      struct mount *mp;
      struct vattr vattr;

      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
            return (error);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      VATTR_NULL(&vattr);
      vattr.va_mode = mode & ALLPERMS;
#ifdef MAC
      error = mac_check_vnode_setmode(td->td_ucred, vp, vattr.va_mode);
      if (error == 0)
#endif
            error = VOP_SETATTR(vp, &vattr, td->td_ucred, td);
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
      return (error);
}

/*
 * Change mode of a file given path name.
 */
#ifndef _SYS_SYSPROTO_H_
struct chmod_args {
      char  *path;
      int   mode;
};
#endif
int
chmod(td, uap)
      struct thread *td;
      register struct chmod_args /* {
            char *path;
            int mode;
      } */ *uap;
{

      return (kern_chmod(td, uap->path, UIO_USERSPACE, uap->mode));
}

int
kern_chmod(struct thread *td, char *path, enum uio_seg pathseg, int mode)
{
      int error;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(mode, mode);
      NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setfmode(td, nd.ni_vp, mode);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Change mode of a file given path name (don't follow links.)
 */
#ifndef _SYS_SYSPROTO_H_
struct lchmod_args {
      char  *path;
      int   mode;
};
#endif
int
lchmod(td, uap)
      struct thread *td;
      register struct lchmod_args /* {
            char *path;
            int mode;
      } */ *uap;
{
      int error;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(mode, (mode_t)uap->mode);
      NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setfmode(td, nd.ni_vp, uap->mode);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Change mode of a file given a file descriptor.
 */
#ifndef _SYS_SYSPROTO_H_
struct fchmod_args {
      int   fd;
      int   mode;
};
#endif
int
fchmod(td, uap)
      struct thread *td;
      register struct fchmod_args /* {
            int fd;
            int mode;
      } */ *uap;
{
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(mode, uap->mode);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
#ifdef AUDIT
      vn_lock(fp->f_vnode, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, fp->f_vnode, ARG_VNODE1);
      VOP_UNLOCK(fp->f_vnode, 0, td);
#endif
      error = setfmode(td, fp->f_vnode, uap->mode);
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Common implementation for chown(), lchown(), and fchown()
 */
static int
setfown(td, vp, uid, gid)
      struct thread *td;
      struct vnode *vp;
      uid_t uid;
      gid_t gid;
{
      int error;
      struct mount *mp;
      struct vattr vattr;

      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
            return (error);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      VATTR_NULL(&vattr);
      vattr.va_uid = uid;
      vattr.va_gid = gid;
#ifdef MAC
      error = mac_check_vnode_setowner(td->td_ucred, vp, vattr.va_uid,
          vattr.va_gid);
      if (error == 0)
#endif
            error = VOP_SETATTR(vp, &vattr, td->td_ucred, td);
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
      return (error);
}

/*
 * Set ownership given a path name.
 */
#ifndef _SYS_SYSPROTO_H_
struct chown_args {
      char  *path;
      int   uid;
      int   gid;
};
#endif
int
chown(td, uap)
      struct thread *td;
      register struct chown_args /* {
            char *path;
            int uid;
            int gid;
      } */ *uap;
{

      return (kern_chown(td, uap->path, UIO_USERSPACE, uap->uid, uap->gid));
}

int
kern_chown(struct thread *td, char *path, enum uio_seg pathseg, int uid,
    int gid)
{
      int error;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(owner, uid, gid);
      NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, pathseg, path,
          td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setfown(td, nd.ni_vp, uid, gid);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Set ownership given a path name, do not cross symlinks.
 */
#ifndef _SYS_SYSPROTO_H_
struct lchown_args {
      char  *path;
      int   uid;
      int   gid;
};
#endif
int
lchown(td, uap)
      struct thread *td;
      register struct lchown_args /* {
            char *path;
            int uid;
            int gid;
      } */ *uap;
{

      return (kern_lchown(td, uap->path, UIO_USERSPACE, uap->uid, uap->gid));
}

int
kern_lchown(struct thread *td, char *path, enum uio_seg pathseg, int uid,
    int gid)
{
      int error;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(owner, uid, gid);
      NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE | AUDITVNODE1, pathseg, path,
          td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setfown(td, nd.ni_vp, uid, gid);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Set ownership given a file descriptor.
 */
#ifndef _SYS_SYSPROTO_H_
struct fchown_args {
      int   fd;
      int   uid;
      int   gid;
};
#endif
int
fchown(td, uap)
      struct thread *td;
      register struct fchown_args /* {
            int fd;
            int uid;
            int gid;
      } */ *uap;
{
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(owner, uap->uid, uap->gid);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
#ifdef AUDIT
      vn_lock(fp->f_vnode, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, fp->f_vnode, ARG_VNODE1);
      VOP_UNLOCK(fp->f_vnode, 0, td);
#endif
      error = setfown(td, fp->f_vnode, uap->uid, uap->gid);
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Common implementation code for utimes(), lutimes(), and futimes().
 */
static int
getutimes(usrtvp, tvpseg, tsp)
      const struct timeval *usrtvp;
      enum uio_seg tvpseg;
      struct timespec *tsp;
{
      struct timeval tv[2];
      const struct timeval *tvp;
      int error;

      if (usrtvp == NULL) {
            microtime(&tv[0]);
            TIMEVAL_TO_TIMESPEC(&tv[0], &tsp[0]);
            tsp[1] = tsp[0];
      } else {
            if (tvpseg == UIO_SYSSPACE) {
                  tvp = usrtvp;
            } else {
                  if ((error = copyin(usrtvp, tv, sizeof(tv))) != 0)
                        return (error);
                  tvp = tv;
            }

            if (tvp[0].tv_usec < 0 || tvp[0].tv_usec >= 1000000 ||
                tvp[1].tv_usec < 0 || tvp[1].tv_usec >= 1000000)
                  return (EINVAL);
            TIMEVAL_TO_TIMESPEC(&tvp[0], &tsp[0]);
            TIMEVAL_TO_TIMESPEC(&tvp[1], &tsp[1]);
      }
      return (0);
}

/*
 * Common implementation code for utimes(), lutimes(), and futimes().
 */
static int
setutimes(td, vp, ts, numtimes, nullflag)
      struct thread *td;
      struct vnode *vp;
      const struct timespec *ts;
      int numtimes;
      int nullflag;
{
      int error, setbirthtime;
      struct mount *mp;
      struct vattr vattr;

      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
            return (error);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      setbirthtime = 0;
      if (numtimes < 3 && VOP_GETATTR(vp, &vattr, td->td_ucred, td) == 0 &&
          timespeccmp(&ts[1], &vattr.va_birthtime, < ))
            setbirthtime = 1;
      VATTR_NULL(&vattr);
      vattr.va_atime = ts[0];
      vattr.va_mtime = ts[1];
      if (setbirthtime)
            vattr.va_birthtime = ts[1];
      if (numtimes > 2)
            vattr.va_birthtime = ts[2];
      if (nullflag)
            vattr.va_vaflags |= VA_UTIMES_NULL;
#ifdef MAC
      error = mac_check_vnode_setutimes(td->td_ucred, vp, vattr.va_atime,
          vattr.va_mtime);
#endif
      if (error == 0)
            error = VOP_SETATTR(vp, &vattr, td->td_ucred, td);
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
      return (error);
}

/*
 * Set the access and modification times of a file.
 */
#ifndef _SYS_SYSPROTO_H_
struct utimes_args {
      char  *path;
      struct      timeval *tptr;
};
#endif
int
utimes(td, uap)
      struct thread *td;
      register struct utimes_args /* {
            char *path;
            struct timeval *tptr;
      } */ *uap;
{

      return (kern_utimes(td, uap->path, UIO_USERSPACE, uap->tptr,
          UIO_USERSPACE));
}

int
kern_utimes(struct thread *td, char *path, enum uio_seg pathseg,
    struct timeval *tptr, enum uio_seg tptrseg)
{
      struct timespec ts[2];
      int error;
      struct nameidata nd;
      int vfslocked;

      if ((error = getutimes(tptr, tptrseg, ts)) != 0)
            return (error);
      NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Set the access and modification times of a file.
 */
#ifndef _SYS_SYSPROTO_H_
struct lutimes_args {
      char  *path;
      struct      timeval *tptr;
};
#endif
int
lutimes(td, uap)
      struct thread *td;
      register struct lutimes_args /* {
            char *path;
            struct timeval *tptr;
      } */ *uap;
{

      return (kern_lutimes(td, uap->path, UIO_USERSPACE, uap->tptr,
          UIO_USERSPACE));
}

int
kern_lutimes(struct thread *td, char *path, enum uio_seg pathseg,
    struct timeval *tptr, enum uio_seg tptrseg)
{
      struct timespec ts[2];
      int error;
      struct nameidata nd;
      int vfslocked;

      if ((error = getutimes(tptr, tptrseg, ts)) != 0)
            return (error);
      NDINIT(&nd, LOOKUP, NOFOLLOW | MPSAFE | AUDITVNODE1, pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      error = setutimes(td, nd.ni_vp, ts, 2, tptr == NULL);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Set the access and modification times of a file.
 */
#ifndef _SYS_SYSPROTO_H_
struct futimes_args {
      int   fd;
      struct      timeval *tptr;
};
#endif
int
futimes(td, uap)
      struct thread *td;
      register struct futimes_args /* {
            int  fd;
            struct timeval *tptr;
      } */ *uap;
{

      return (kern_futimes(td, uap->fd, uap->tptr, UIO_USERSPACE));
}

int
kern_futimes(struct thread *td, int fd, struct timeval *tptr,
    enum uio_seg tptrseg)
{
      struct timespec ts[2];
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, fd);
      if ((error = getutimes(tptr, tptrseg, ts)) != 0)
            return (error);
      if ((error = getvnode(td->td_proc->p_fd, fd, &fp)) != 0)
            return (error);
      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
#ifdef AUDIT
      vn_lock(fp->f_vnode, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, fp->f_vnode, ARG_VNODE1);
      VOP_UNLOCK(fp->f_vnode, 0, td);
#endif
      error = setutimes(td, fp->f_vnode, ts, 2, tptr == NULL);
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Truncate a file given its path name.
 */
#ifndef _SYS_SYSPROTO_H_
struct truncate_args {
      char  *path;
      int   pad;
      off_t length;
};
#endif
int
truncate(td, uap)
      struct thread *td;
      register struct truncate_args /* {
            char *path;
            int pad;
            off_t length;
      } */ *uap;
{

      return (kern_truncate(td, uap->path, UIO_USERSPACE, uap->length));
}

int
kern_truncate(struct thread *td, char *path, enum uio_seg pathseg, off_t length)
{
      struct mount *mp;
      struct vnode *vp;
      struct vattr vattr;
      int error;
      struct nameidata nd;
      int vfslocked;

      if (length < 0)
            return(EINVAL);
      NDINIT(&nd, LOOKUP, FOLLOW | MPSAFE | AUDITVNODE1, pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0) {
            vrele(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (error);
      }
      NDFREE(&nd, NDF_ONLY_PNBUF);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      if (vp->v_type == VDIR)
            error = EISDIR;
#ifdef MAC
      else if ((error = mac_check_vnode_write(td->td_ucred, NOCRED, vp))) {
      }
#endif
      else if ((error = vn_writechk(vp)) == 0 &&
          (error = VOP_ACCESS(vp, VWRITE, td->td_ucred, td)) == 0) {
            VATTR_NULL(&vattr);
            vattr.va_size = length;
            error = VOP_SETATTR(vp, &vattr, td->td_ucred, td);
      }
      vput(vp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Truncate a file given a file descriptor.
 */
#ifndef _SYS_SYSPROTO_H_
struct ftruncate_args {
      int   fd;
      int   pad;
      off_t length;
};
#endif
int
ftruncate(td, uap)
      struct thread *td;
      register struct ftruncate_args /* {
            int fd;
            int pad;
            off_t length;
      } */ *uap;
{
      struct mount *mp;
      struct vattr vattr;
      struct vnode *vp;
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, uap->fd);
      if (uap->length < 0)
            return(EINVAL);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      if ((fp->f_flag & FWRITE) == 0) {
            fdrop(fp, td);
            return (EINVAL);
      }
      vp = fp->f_vnode;
      vfslocked = VFS_LOCK_GIANT(vp->v_mount);
      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
            goto drop;
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, vp, ARG_VNODE1);
      if (vp->v_type == VDIR)
            error = EISDIR;
#ifdef MAC
      else if ((error = mac_check_vnode_write(td->td_ucred, fp->f_cred,
          vp))) {
      }
#endif
      else if ((error = vn_writechk(vp)) == 0) {
            VATTR_NULL(&vattr);
            vattr.va_size = uap->length;
            error = VOP_SETATTR(vp, &vattr, fp->f_cred, td);
      }
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
drop:
      VFS_UNLOCK_GIANT(vfslocked);
      fdrop(fp, td);
      return (error);
}

#if defined(COMPAT_43)
/*
 * Truncate a file given its path name.
 */
#ifndef _SYS_SYSPROTO_H_
struct otruncate_args {
      char  *path;
      long  length;
};
#endif
int
otruncate(td, uap)
      struct thread *td;
      register struct otruncate_args /* {
            char *path;
            long length;
      } */ *uap;
{
      struct truncate_args /* {
            char *path;
            int pad;
            off_t length;
      } */ nuap;

      nuap.path = uap->path;
      nuap.length = uap->length;
      return (truncate(td, &nuap));
}

/*
 * Truncate a file given a file descriptor.
 */
#ifndef _SYS_SYSPROTO_H_
struct oftruncate_args {
      int   fd;
      long  length;
};
#endif
int
oftruncate(td, uap)
      struct thread *td;
      register struct oftruncate_args /* {
            int fd;
            long length;
      } */ *uap;
{
      struct ftruncate_args /* {
            int fd;
            int pad;
            off_t length;
      } */ nuap;

      nuap.fd = uap->fd;
      nuap.length = uap->length;
      return (ftruncate(td, &nuap));
}
#endif /* COMPAT_43 */

/*
 * Sync an open file.
 */
#ifndef _SYS_SYSPROTO_H_
struct fsync_args {
      int   fd;
};
#endif
int
fsync(td, uap)
      struct thread *td;
      struct fsync_args /* {
            int fd;
      } */ *uap;
{
      struct vnode *vp;
      struct mount *mp;
      struct file *fp;
      int vfslocked;
      int error;

      AUDIT_ARG(fd, uap->fd);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      vp = fp->f_vnode;
      vfslocked = VFS_LOCK_GIANT(vp->v_mount);
      if ((error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
            goto drop;
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, vp, ARG_VNODE1);
      if (vp->v_object != NULL) {
            VM_OBJECT_LOCK(vp->v_object);
            vm_object_page_clean(vp->v_object, 0, 0, 0);
            VM_OBJECT_UNLOCK(vp->v_object);
      }
      error = VOP_FSYNC(vp, MNT_WAIT, td);

      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
drop:
      VFS_UNLOCK_GIANT(vfslocked);
      fdrop(fp, td);
      return (error);
}

/*
 * Rename files.  Source and destination must either both be directories,
 * or both not be directories.  If target is a directory, it must be empty.
 */
#ifndef _SYS_SYSPROTO_H_
struct rename_args {
      char  *from;
      char  *to;
};
#endif
int
rename(td, uap)
      struct thread *td;
      register struct rename_args /* {
            char *from;
            char *to;
      } */ *uap;
{

      return (kern_rename(td, uap->from, uap->to, UIO_USERSPACE));
}

int
kern_rename(struct thread *td, char *from, char *to, enum uio_seg pathseg)
{
      struct mount *mp = NULL;
      struct vnode *tvp, *fvp, *tdvp;
      struct nameidata fromnd, tond;
      int tvfslocked;
      int fvfslocked;
      int error;

      bwillwrite();
#ifdef MAC
      NDINIT(&fromnd, DELETE, LOCKPARENT | LOCKLEAF | SAVESTART | MPSAFE |
          AUDITVNODE1, pathseg, from, td);
#else
      NDINIT(&fromnd, DELETE, WANTPARENT | SAVESTART | MPSAFE |
          AUDITVNODE1, pathseg, from, td);
#endif
      if ((error = namei(&fromnd)) != 0)
            return (error);
      fvfslocked = NDHASGIANT(&fromnd);
      tvfslocked = 0;
#ifdef MAC
      error = mac_check_vnode_rename_from(td->td_ucred, fromnd.ni_dvp,
          fromnd.ni_vp, &fromnd.ni_cnd);
      VOP_UNLOCK(fromnd.ni_dvp, 0, td);
      if (fromnd.ni_dvp != fromnd.ni_vp)
            VOP_UNLOCK(fromnd.ni_vp, 0, td);
#endif
      fvp = fromnd.ni_vp;
      if (error == 0)
            error = vn_start_write(fvp, &mp, V_WAIT | PCATCH);
      if (error != 0) {
            NDFREE(&fromnd, NDF_ONLY_PNBUF);
            vrele(fromnd.ni_dvp);
            vrele(fvp);
            goto out1;
      }
      NDINIT(&tond, RENAME, LOCKPARENT | LOCKLEAF | NOCACHE | SAVESTART |
          MPSAFE | AUDITVNODE2, pathseg, to, td);
      if (fromnd.ni_vp->v_type == VDIR)
            tond.ni_cnd.cn_flags |= WILLBEDIR;
      if ((error = namei(&tond)) != 0) {
            /* Translate error code for rename("dir1", "dir2/."). */
            if (error == EISDIR && fvp->v_type == VDIR)
                  error = EINVAL;
            NDFREE(&fromnd, NDF_ONLY_PNBUF);
            vrele(fromnd.ni_dvp);
            vrele(fvp);
            vn_finished_write(mp);
            goto out1;
      }
      tvfslocked = NDHASGIANT(&tond);
      tdvp = tond.ni_dvp;
      tvp = tond.ni_vp;
      if (tvp != NULL) {
            if (fvp->v_type == VDIR && tvp->v_type != VDIR) {
                  error = ENOTDIR;
                  goto out;
            } else if (fvp->v_type != VDIR && tvp->v_type == VDIR) {
                  error = EISDIR;
                  goto out;
            }
      }
      if (fvp == tdvp)
            error = EINVAL;
      /*
       * If the source is the same as the destination (that is, if they
       * are links to the same vnode), then there is nothing to do.
       */
      if (fvp == tvp)
            error = -1;
#ifdef MAC
      else
            error = mac_check_vnode_rename_to(td->td_ucred, tdvp,
                tond.ni_vp, fromnd.ni_dvp == tdvp, &tond.ni_cnd);
#endif
out:
      if (!error) {
            VOP_LEASE(tdvp, td, td->td_ucred, LEASE_WRITE);
            if (fromnd.ni_dvp != tdvp) {
                  VOP_LEASE(fromnd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
            }
            if (tvp) {
                  VOP_LEASE(tvp, td, td->td_ucred, LEASE_WRITE);
            }
            error = VOP_RENAME(fromnd.ni_dvp, fromnd.ni_vp, &fromnd.ni_cnd,
                           tond.ni_dvp, tond.ni_vp, &tond.ni_cnd);
            NDFREE(&fromnd, NDF_ONLY_PNBUF);
            NDFREE(&tond, NDF_ONLY_PNBUF);
      } else {
            NDFREE(&fromnd, NDF_ONLY_PNBUF);
            NDFREE(&tond, NDF_ONLY_PNBUF);
            if (tvp)
                  vput(tvp);
            if (tdvp == tvp)
                  vrele(tdvp);
            else
                  vput(tdvp);
            vrele(fromnd.ni_dvp);
            vrele(fvp);
      }
      vrele(tond.ni_startdir);
      vn_finished_write(mp);
out1:
      if (fromnd.ni_startdir)
            vrele(fromnd.ni_startdir);
      VFS_UNLOCK_GIANT(fvfslocked);
      VFS_UNLOCK_GIANT(tvfslocked);
      if (error == -1)
            return (0);
      return (error);
}

/*
 * Make a directory file.
 */
#ifndef _SYS_SYSPROTO_H_
struct mkdir_args {
      char  *path;
      int   mode;
};
#endif
int
mkdir(td, uap)
      struct thread *td;
      register struct mkdir_args /* {
            char *path;
            int mode;
      } */ *uap;
{

      return (kern_mkdir(td, uap->path, UIO_USERSPACE, uap->mode));
}

int
kern_mkdir(struct thread *td, char *path, enum uio_seg segflg, int mode)
{
      struct mount *mp;
      struct vnode *vp;
      struct vattr vattr;
      int error;
      struct nameidata nd;
      int vfslocked;

      AUDIT_ARG(mode, mode);
restart:
      bwillwrite();
      NDINIT(&nd, CREATE, LOCKPARENT | SAVENAME | MPSAFE | AUDITVNODE1,
          segflg, path, td);
      nd.ni_cnd.cn_flags |= WILLBEDIR;
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      if (vp != NULL) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            /*
             * XXX namei called with LOCKPARENT but not LOCKLEAF has
             * the strange behaviour of leaving the vnode unlocked
             * if the target is the same vnode as the parent.
             */
            if (vp == nd.ni_dvp)
                  vrele(nd.ni_dvp);
            else
                  vput(nd.ni_dvp);
            vrele(vp);
            VFS_UNLOCK_GIANT(vfslocked);
            return (EEXIST);
      }
      if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            vput(nd.ni_dvp);
            VFS_UNLOCK_GIANT(vfslocked);
            if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
                  return (error);
            goto restart;
      }
      VATTR_NULL(&vattr);
      vattr.va_type = VDIR;
      FILEDESC_LOCK_FAST(td->td_proc->p_fd);
      vattr.va_mode = (mode & ACCESSPERMS) &~ td->td_proc->p_fd->fd_cmask;
      FILEDESC_UNLOCK_FAST(td->td_proc->p_fd);
#ifdef MAC
      error = mac_check_vnode_create(td->td_ucred, nd.ni_dvp, &nd.ni_cnd,
          &vattr);
      if (error)
            goto out;
#endif
      VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
      error = VOP_MKDIR(nd.ni_dvp, &nd.ni_vp, &nd.ni_cnd, &vattr);
#ifdef MAC
out:
#endif
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(nd.ni_dvp);
      if (!error)
            vput(nd.ni_vp);
      vn_finished_write(mp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Remove a directory file.
 */
#ifndef _SYS_SYSPROTO_H_
struct rmdir_args {
      char  *path;
};
#endif
int
rmdir(td, uap)
      struct thread *td;
      struct rmdir_args /* {
            char *path;
      } */ *uap;
{

      return (kern_rmdir(td, uap->path, UIO_USERSPACE));
}

int
kern_rmdir(struct thread *td, char *path, enum uio_seg pathseg)
{
      struct mount *mp;
      struct vnode *vp;
      int error;
      struct nameidata nd;
      int vfslocked;

restart:
      bwillwrite();
      NDINIT(&nd, DELETE, LOCKPARENT | LOCKLEAF | MPSAFE | AUDITVNODE1,
          pathseg, path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      if (vp->v_type != VDIR) {
            error = ENOTDIR;
            goto out;
      }
      /*
       * No rmdir "." please.
       */
      if (nd.ni_dvp == vp) {
            error = EINVAL;
            goto out;
      }
      /*
       * The root of a mounted filesystem cannot be deleted.
       */
      if (vp->v_vflag & VV_ROOT) {
            error = EBUSY;
            goto out;
      }
#ifdef MAC
      error = mac_check_vnode_delete(td->td_ucred, nd.ni_dvp, vp,
          &nd.ni_cnd);
      if (error)
            goto out;
#endif
      if (vn_start_write(nd.ni_dvp, &mp, V_NOWAIT) != 0) {
            NDFREE(&nd, NDF_ONLY_PNBUF);
            vput(vp);
            if (nd.ni_dvp == vp)
                  vrele(nd.ni_dvp);
            else
                  vput(nd.ni_dvp);
            VFS_UNLOCK_GIANT(vfslocked);
            if ((error = vn_start_write(NULL, &mp, V_XSLEEP | PCATCH)) != 0)
                  return (error);
            goto restart;
      }
      VOP_LEASE(nd.ni_dvp, td, td->td_ucred, LEASE_WRITE);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      error = VOP_RMDIR(nd.ni_dvp, nd.ni_vp, &nd.ni_cnd);
      vn_finished_write(mp);
out:
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vput(vp);
      if (nd.ni_dvp == vp)
            vrele(nd.ni_dvp);
      else
            vput(nd.ni_dvp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

#ifdef COMPAT_43
/*
 * Read a block of directory entries in a filesystem independent format.
 */
#ifndef _SYS_SYSPROTO_H_
struct ogetdirentries_args {
      int   fd;
      char  *buf;
      u_int count;
      long  *basep;
};
#endif
int
ogetdirentries(td, uap)
      struct thread *td;
      register struct ogetdirentries_args /* {
            int fd;
            char *buf;
            u_int count;
            long *basep;
      } */ *uap;
{
      struct vnode *vp;
      struct file *fp;
      struct uio auio, kuio;
      struct iovec aiov, kiov;
      struct dirent *dp, *edp;
      caddr_t dirbuf;
      int error, eofflag, readcnt;
      long loff;

      /* XXX arbitrary sanity limit on `count'. */
      if (uap->count > 64 * 1024)
            return (EINVAL);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      if ((fp->f_flag & FREAD) == 0) {
            fdrop(fp, td);
            return (EBADF);
      }
      vp = fp->f_vnode;
unionread:
      if (vp->v_type != VDIR) {
            fdrop(fp, td);
            return (EINVAL);
      }
      aiov.iov_base = uap->buf;
      aiov.iov_len = uap->count;
      auio.uio_iov = &aiov;
      auio.uio_iovcnt = 1;
      auio.uio_rw = UIO_READ;
      auio.uio_segflg = UIO_USERSPACE;
      auio.uio_td = td;
      auio.uio_resid = uap->count;
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      loff = auio.uio_offset = fp->f_offset;
#ifdef MAC
      error = mac_check_vnode_readdir(td->td_ucred, vp);
      if (error) {
            VOP_UNLOCK(vp, 0, td);
            fdrop(fp, td);
            return (error);
      }
#endif
#     if (BYTE_ORDER != LITTLE_ENDIAN)
            if (vp->v_mount->mnt_maxsymlinklen <= 0) {
                  error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag,
                      NULL, NULL);
                  fp->f_offset = auio.uio_offset;
            } else
#     endif
      {
            kuio = auio;
            kuio.uio_iov = &kiov;
            kuio.uio_segflg = UIO_SYSSPACE;
            kiov.iov_len = uap->count;
            MALLOC(dirbuf, caddr_t, uap->count, M_TEMP, M_WAITOK);
            kiov.iov_base = dirbuf;
            error = VOP_READDIR(vp, &kuio, fp->f_cred, &eofflag,
                      NULL, NULL);
            fp->f_offset = kuio.uio_offset;
            if (error == 0) {
                  readcnt = uap->count - kuio.uio_resid;
                  edp = (struct dirent *)&dirbuf[readcnt];
                  for (dp = (struct dirent *)dirbuf; dp < edp; ) {
#                       if (BYTE_ORDER == LITTLE_ENDIAN)
                              /*
                               * The expected low byte of
                               * dp->d_namlen is our dp->d_type.
                               * The high MBZ byte of dp->d_namlen
                               * is our dp->d_namlen.
                               */
                              dp->d_type = dp->d_namlen;
                              dp->d_namlen = 0;
#                       else
                              /*
                               * The dp->d_type is the high byte
                               * of the expected dp->d_namlen,
                               * so must be zero'ed.
                               */
                              dp->d_type = 0;
#                       endif
                        if (dp->d_reclen > 0) {
                              dp = (struct dirent *)
                                  ((char *)dp + dp->d_reclen);
                        } else {
                              error = EIO;
                              break;
                        }
                  }
                  if (dp >= edp)
                        error = uiomove(dirbuf, readcnt, &auio);
            }
            FREE(dirbuf, M_TEMP);
      }
      if (error) {
            VOP_UNLOCK(vp, 0, td);
            fdrop(fp, td);
            return (error);
      }
      if (uap->count == auio.uio_resid &&
          (vp->v_vflag & VV_ROOT) &&
          (vp->v_mount->mnt_flag & MNT_UNION)) {
            struct vnode *tvp = vp;
            vp = vp->v_mount->mnt_vnodecovered;
            VREF(vp);
            fp->f_vnode = vp;
            fp->f_data = vp;
            fp->f_offset = 0;
            vput(tvp);
            goto unionread;
      }
      VOP_UNLOCK(vp, 0, td);
      error = copyout(&loff, uap->basep, sizeof(long));
      fdrop(fp, td);
      td->td_retval[0] = uap->count - auio.uio_resid;
      return (error);
}
#endif /* COMPAT_43 */

/*
 * Read a block of directory entries in a filesystem independent format.
 */
#ifndef _SYS_SYSPROTO_H_
struct getdirentries_args {
      int   fd;
      char  *buf;
      u_int count;
      long  *basep;
};
#endif
int
getdirentries(td, uap)
      struct thread *td;
      register struct getdirentries_args /* {
            int fd;
            char *buf;
            u_int count;
            long *basep;
      } */ *uap;
{
      struct vnode *vp;
      struct file *fp;
      struct uio auio;
      struct iovec aiov;
      int vfslocked;
      long loff;
      int error, eofflag;

      AUDIT_ARG(fd, uap->fd);
      if ((error = getvnode(td->td_proc->p_fd, uap->fd, &fp)) != 0)
            return (error);
      if ((fp->f_flag & FREAD) == 0) {
            fdrop(fp, td);
            return (EBADF);
      }
      vp = fp->f_vnode;
unionread:
      vfslocked = VFS_LOCK_GIANT(vp->v_mount);
      if (vp->v_type != VDIR) {
            VFS_UNLOCK_GIANT(vfslocked);
            error = EINVAL;
            goto fail;
      }
      aiov.iov_base = uap->buf;
      aiov.iov_len = uap->count;
      auio.uio_iov = &aiov;
      auio.uio_iovcnt = 1;
      auio.uio_rw = UIO_READ;
      auio.uio_segflg = UIO_USERSPACE;
      auio.uio_td = td;
      auio.uio_resid = uap->count;
      /* vn_lock(vp, LK_SHARED | LK_RETRY, td); */
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
      AUDIT_ARG(vnode, vp, ARG_VNODE1);
      loff = auio.uio_offset = fp->f_offset;
#ifdef MAC
      error = mac_check_vnode_readdir(td->td_ucred, vp);
      if (error == 0)
#endif
            error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag, NULL,
                NULL);
      fp->f_offset = auio.uio_offset;
      if (error) {
            VOP_UNLOCK(vp, 0, td);
            VFS_UNLOCK_GIANT(vfslocked);
            goto fail;
      }
      if (uap->count == auio.uio_resid &&
          (vp->v_vflag & VV_ROOT) &&
          (vp->v_mount->mnt_flag & MNT_UNION)) {
            struct vnode *tvp = vp;
            vp = vp->v_mount->mnt_vnodecovered;
            VREF(vp);
            fp->f_vnode = vp;
            fp->f_data = vp;
            fp->f_offset = 0;
            vput(tvp);
            VFS_UNLOCK_GIANT(vfslocked);
            goto unionread;
      }
      VOP_UNLOCK(vp, 0, td);
      VFS_UNLOCK_GIANT(vfslocked);
      if (uap->basep != NULL) {
            error = copyout(&loff, uap->basep, sizeof(long));
      }
      td->td_retval[0] = uap->count - auio.uio_resid;
fail:
      fdrop(fp, td);
      return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct getdents_args {
      int fd;
      char *buf;
      size_t count;
};
#endif
int
getdents(td, uap)
      struct thread *td;
      register struct getdents_args /* {
            int fd;
            char *buf;
            u_int count;
      } */ *uap;
{
      struct getdirentries_args ap;
      ap.fd = uap->fd;
      ap.buf = uap->buf;
      ap.count = uap->count;
      ap.basep = NULL;
      return (getdirentries(td, &ap));
}

/*
 * Set the mode mask for creation of filesystem nodes.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct umask_args {
      int   newmask;
};
#endif
int
umask(td, uap)
      struct thread *td;
      struct umask_args /* {
            int newmask;
      } */ *uap;
{
      register struct filedesc *fdp;

      FILEDESC_LOCK_FAST(td->td_proc->p_fd);
      fdp = td->td_proc->p_fd;
      td->td_retval[0] = fdp->fd_cmask;
      fdp->fd_cmask = uap->newmask & ALLPERMS;
      FILEDESC_UNLOCK_FAST(td->td_proc->p_fd);
      return (0);
}

/*
 * Void all references to file by ripping underlying filesystem
 * away from vnode.
 */
#ifndef _SYS_SYSPROTO_H_
struct revoke_args {
      char  *path;
};
#endif
int
revoke(td, uap)
      struct thread *td;
      register struct revoke_args /* {
            char *path;
      } */ *uap;
{
      struct vnode *vp;
      struct vattr vattr;
      int error;
      struct nameidata nd;
      int vfslocked;

      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          UIO_USERSPACE, uap->path, td);
      if ((error = namei(&nd)) != 0)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      vp = nd.ni_vp;
      NDFREE(&nd, NDF_ONLY_PNBUF);
      if (vp->v_type != VCHR) {
            error = EINVAL;
            goto out;
      }
#ifdef MAC
      error = mac_check_vnode_revoke(td->td_ucred, vp);
      if (error)
            goto out;
#endif
      error = VOP_GETATTR(vp, &vattr, td->td_ucred, td);
      if (error)
            goto out;
      if (td->td_ucred->cr_uid != vattr.va_uid) {
            error = suser_cred(td->td_ucred, SUSER_ALLOWJAIL);
            if (error)
                  goto out;
      }
      if (vcount(vp) > 1)
            VOP_REVOKE(vp, REVOKEALL);
out:
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * Convert a user file descriptor to a kernel file entry.
 * A reference on the file entry is held upon returning.
 */
int
getvnode(fdp, fd, fpp)
      struct filedesc *fdp;
      int fd;
      struct file **fpp;
{
      int error;
      struct file *fp;

      fp = NULL;
      if (fdp == NULL)
            error = EBADF;
      else {
            FILEDESC_LOCK(fdp);
            if ((u_int)fd >= fdp->fd_nfiles ||
                (fp = fdp->fd_ofiles[fd]) == NULL)
                  error = EBADF;
            else if (fp->f_vnode == NULL) {
                  fp = NULL;
                  error = EINVAL;
            } else {
                  fhold(fp);
                  error = 0;
            }
            FILEDESC_UNLOCK(fdp);
      }
      *fpp = fp;
      return (error);
}

/*
 * Get (NFS) file handle
 */
#ifndef _SYS_SYSPROTO_H_
struct lgetfh_args {
      char  *fname;
      fhandle_t *fhp;
};
#endif
int
lgetfh(td, uap)
      struct thread *td;
      register struct lgetfh_args *uap;
{
      struct nameidata nd;
      fhandle_t fh;
      register struct vnode *vp;
      int vfslocked;
      int error;

      error = suser(td);
      if (error)
            return (error);
      NDINIT(&nd, LOOKUP, NOFOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          UIO_USERSPACE, uap->fname, td);
      error = namei(&nd);
      if (error)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vp = nd.ni_vp;
      bzero(&fh, sizeof(fh));
      fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
      error = VFS_VPTOFH(vp, &fh.fh_fid);
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      if (error)
            return (error);
      error = copyout(&fh, uap->fhp, sizeof (fh));
      return (error);
}

#ifndef _SYS_SYSPROTO_H_
struct getfh_args {
      char  *fname;
      fhandle_t *fhp;
};
#endif
int
getfh(td, uap)
      struct thread *td;
      register struct getfh_args *uap;
{
      struct nameidata nd;
      fhandle_t fh;
      register struct vnode *vp;
      int vfslocked;
      int error;

      error = suser(td);
      if (error)
            return (error);
      NDINIT(&nd, LOOKUP, FOLLOW | LOCKLEAF | MPSAFE | AUDITVNODE1,
          UIO_USERSPACE, uap->fname, td);
      error = namei(&nd);
      if (error)
            return (error);
      vfslocked = NDHASGIANT(&nd);
      NDFREE(&nd, NDF_ONLY_PNBUF);
      vp = nd.ni_vp;
      bzero(&fh, sizeof(fh));
      fh.fh_fsid = vp->v_mount->mnt_stat.f_fsid;
      error = VFS_VPTOFH(vp, &fh.fh_fid);
      vput(vp);
      VFS_UNLOCK_GIANT(vfslocked);
      if (error)
            return (error);
      error = copyout(&fh, uap->fhp, sizeof (fh));
      return (error);
}

/*
 * syscall for the rpc.lockd to use to translate a NFS file handle into
 * an open descriptor.
 *
 * warning: do not remove the suser() call or this becomes one giant
 * security hole.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct fhopen_args {
      const struct fhandle *u_fhp;
      int flags;
};
#endif
int
fhopen(td, uap)
      struct thread *td;
      struct fhopen_args /* {
            const struct fhandle *u_fhp;
            int flags;
      } */ *uap;
{
      struct proc *p = td->td_proc;
      struct mount *mp;
      struct vnode *vp;
      struct fhandle fhp;
      struct vattr vat;
      struct vattr *vap = &vat;
      struct flock lf;
      struct file *fp;
      register struct filedesc *fdp = p->p_fd;
      int fmode, mode, error, type;
      struct file *nfp;
      int indx;

      error = suser(td);
      if (error)
            return (error);
      fmode = FFLAGS(uap->flags);
      /* why not allow a non-read/write open for our lockd? */
      if (((fmode & (FREAD | FWRITE)) == 0) || (fmode & O_CREAT))
            return (EINVAL);
      error = copyin(uap->u_fhp, &fhp, sizeof(fhp));
      if (error)
            return(error);
      /* find the mount point */
      mtx_lock(&Giant);
      mp = vfs_getvfs(&fhp.fh_fsid);
      if (mp == NULL) {
            error = ESTALE;
            goto out_nomp;
      }
      /* now give me my vnode, it gets returned to me locked */
      error = VFS_FHTOVP(mp, &fhp.fh_fid, &vp);
      if (error)
            goto out;
      /*
       * from now on we have to make sure not
       * to forget about the vnode
       * any error that causes an abort must vput(vp)
       * just set error = err and 'goto bad;'.
       */

      /*
       * from vn_open
       */
      if (vp->v_type == VLNK) {
            error = EMLINK;
            goto bad;
      }
      if (vp->v_type == VSOCK) {
            error = EOPNOTSUPP;
            goto bad;
      }
      mode = 0;
      if (fmode & (FWRITE | O_TRUNC)) {
            if (vp->v_type == VDIR) {
                  error = EISDIR;
                  goto bad;
            }
            error = vn_writechk(vp);
            if (error)
                  goto bad;
            mode |= VWRITE;
      }
      if (fmode & FREAD)
            mode |= VREAD;
      if (fmode & O_APPEND)
            mode |= VAPPEND;
#ifdef MAC
      error = mac_check_vnode_open(td->td_ucred, vp, mode);
      if (error)
            goto bad;
#endif
      if (mode) {
            error = VOP_ACCESS(vp, mode, td->td_ucred, td);
            if (error)
                  goto bad;
      }
      if (fmode & O_TRUNC) {
            VOP_UNLOCK(vp, 0, td);                    /* XXX */
            if ((error = vn_start_write(NULL, &mp, V_WAIT | PCATCH)) != 0) {
                  vrele(vp);
                  goto out;
            }
            VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
            vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); /* XXX */
#ifdef MAC
            /*
             * We don't yet have fp->f_cred, so use td->td_ucred, which
             * should be right.
             */
            error = mac_check_vnode_write(td->td_ucred, td->td_ucred, vp);
            if (error == 0) {
#endif
                  VATTR_NULL(vap);
                  vap->va_size = 0;
                  error = VOP_SETATTR(vp, vap, td->td_ucred, td);
#ifdef MAC
            }
#endif
            vn_finished_write(mp);
            if (error)
                  goto bad;
      }
      error = VOP_OPEN(vp, fmode, td->td_ucred, td, -1);
      if (error)
            goto bad;

      if (fmode & FWRITE)
            vp->v_writecount++;

      /*
       * end of vn_open code
       */

      if ((error = falloc(td, &nfp, &indx)) != 0) {
            if (fmode & FWRITE)
                  vp->v_writecount--;
            goto bad;
      }
      /* An extra reference on `nfp' has been held for us by falloc(). */
      fp = nfp;

      nfp->f_vnode = vp;
      nfp->f_data = vp;
      nfp->f_flag = fmode & FMASK;
      nfp->f_ops = &vnops;
      nfp->f_type = DTYPE_VNODE;
      if (fmode & (O_EXLOCK | O_SHLOCK)) {
            lf.l_whence = SEEK_SET;
            lf.l_start = 0;
            lf.l_len = 0;
            if (fmode & O_EXLOCK)
                  lf.l_type = F_WRLCK;
            else
                  lf.l_type = F_RDLCK;
            type = F_FLOCK;
            if ((fmode & FNONBLOCK) == 0)
                  type |= F_WAIT;
            VOP_UNLOCK(vp, 0, td);
            if ((error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf,
                      type)) != 0) {
                  /*
                   * The lock request failed.  Normally close the
                   * descriptor but handle the case where someone might
                   * have dup()d or close()d it when we weren't looking.
                   */
                  fdclose(fdp, fp, indx, td);

                  /*
                   * release our private reference
                   */
                  fdrop(fp, td);
                  goto out;
            }
            vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);
            fp->f_flag |= FHASLOCK;
      }

      VOP_UNLOCK(vp, 0, td);
      fdrop(fp, td);
      vfs_rel(mp);
      mtx_unlock(&Giant);
      td->td_retval[0] = indx;
      return (0);

bad:
      vput(vp);
out:
      vfs_rel(mp);
out_nomp:
      mtx_unlock(&Giant);
      return (error);
}

/*
 * Stat an (NFS) file handle.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct fhstat_args {
      struct fhandle *u_fhp;
      struct stat *sb;
};
#endif
int
fhstat(td, uap)
      struct thread *td;
      register struct fhstat_args /* {
            struct fhandle *u_fhp;
            struct stat *sb;
      } */ *uap;
{
      struct stat sb;
      fhandle_t fh;
      struct mount *mp;
      struct vnode *vp;
      int error;

      error = suser(td);
      if (error)
            return (error);
      error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
      if (error)
            return (error);
      mtx_lock(&Giant);
      if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL) {
            mtx_unlock(&Giant);
            return (ESTALE);
      }
      if ((error = VFS_FHTOVP(mp, &fh.fh_fid, &vp))) {
            vfs_rel(mp);
            mtx_unlock(&Giant);
            return (error);
      }
      error = vn_stat(vp, &sb, td->td_ucred, NOCRED, td);
      vput(vp);
      vfs_rel(mp);
      mtx_unlock(&Giant);
      if (error)
            return (error);
      error = copyout(&sb, uap->sb, sizeof(sb));
      return (error);
}

/*
 * Implement fstatfs() for (NFS) file handles.
 *
 * MP SAFE
 */
#ifndef _SYS_SYSPROTO_H_
struct fhstatfs_args {
      struct fhandle *u_fhp;
      struct statfs *buf;
};
#endif
int
fhstatfs(td, uap)
      struct thread *td;
      struct fhstatfs_args /* {
            struct fhandle *u_fhp;
            struct statfs *buf;
      } */ *uap;
{
      struct statfs sf;
      fhandle_t fh;
      int error;

      error = copyin(uap->u_fhp, &fh, sizeof(fhandle_t));
      if (error)
            return (error);
      error = kern_fhstatfs(td, fh, &sf);
      if (error)
            return (error);
      return (copyout(&sf, uap->buf, sizeof(sf)));
}

int
kern_fhstatfs(struct thread *td, fhandle_t fh, struct statfs *buf)
{
      struct statfs *sp;
      struct mount *mp;
      struct vnode *vp;
      int error;

      error = suser(td);
      if (error)
            return (error);
      mtx_lock(&Giant);
      if ((mp = vfs_getvfs(&fh.fh_fsid)) == NULL) {
            mtx_unlock(&Giant);
            return (ESTALE);
      }
      error = VFS_FHTOVP(mp, &fh.fh_fid, &vp);
      if (error) {
            mtx_unlock(&Giant);
            vfs_rel(mp);
            return (error);
      }
      vput(vp);
      error = prison_canseemount(td->td_ucred, mp);
      if (error) {
            vfs_rel(mp);
            mtx_unlock(&Giant);
            return (error);
      }
#ifdef MAC
      error = mac_check_mount_stat(td->td_ucred, mp);
      if (error) {
            vfs_rel(mp);
            mtx_unlock(&Giant);
            return (error);
      }
#endif
      /*
       * Set these in case the underlying filesystem fails to do so.
       */
      sp = &mp->mnt_stat;
      sp->f_version = STATFS_VERSION;
      sp->f_namemax = NAME_MAX;
      sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
      error = VFS_STATFS(mp, sp, td);
      if (error == 0)
            *buf = *sp;
      vfs_rel(mp);
      mtx_unlock(&Giant);
      return (error);
}

/*
 * Syscall to push extended attribute configuration information into the
 * VFS.  Accepts a path, which it converts to a mountpoint, as well as
 * a command (int cmd), and attribute name and misc data.  For now, the
 * attribute name is left in userspace for consumption by the VFS_op.
 * It will probably be changed to be copied into sysspace by the
 * syscall in the future, once issues with various consumers of the
 * attribute code have raised their hands.
 *
 * Currently this is used only by UFS Extended Attributes.
 */
int
extattrctl(td, uap)
      struct thread *td;
      struct extattrctl_args /* {
            const char *path;
            int cmd;
            const char *filename;
            int attrnamespace;
            const char *attrname;
      } */ *uap;
{
      struct vnode *filename_vp;
      struct nameidata nd;
      struct mount *mp, *mp_writable;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, fnvfslocked, error;

      AUDIT_ARG(cmd, uap->cmd);
      AUDIT_ARG(value, uap->attrnamespace);
      /*
       * uap->attrname is not always defined.  We check again later when we
       * invoke the VFS call so as to pass in NULL there if needed.
       */
      if (uap->attrname != NULL) {
            error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN,
                NULL);
            if (error)
                  return (error);
      }
      AUDIT_ARG(text, attrname);

      vfslocked = fnvfslocked = 0;
      /*
       * uap->filename is not always defined.  If it is, grab a vnode lock,
       * which VFS_EXTATTRCTL() will later release.
       */
      filename_vp = NULL;
      if (uap->filename != NULL) {
            NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | LOCKLEAF |
                AUDITVNODE2, UIO_USERSPACE, uap->filename, td);
            error = namei(&nd);
            if (error)
                  return (error);
            fnvfslocked = NDHASGIANT(&nd);
            filename_vp = nd.ni_vp;
            NDFREE(&nd, NDF_NO_VP_RELE | NDF_NO_VP_UNLOCK);
      }

      /* uap->path is always defined. */
      NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error) {
            if (filename_vp != NULL)
                  vput(filename_vp);
            goto out;
      }
      vfslocked = NDHASGIANT(&nd);
      mp = nd.ni_vp->v_mount;
      error = vn_start_write(nd.ni_vp, &mp_writable, V_WAIT | PCATCH);
      NDFREE(&nd, 0);
      if (error) {
            if (filename_vp != NULL)
                  vput(filename_vp);
            goto out;
      }

      error = VFS_EXTATTRCTL(mp, uap->cmd, filename_vp, uap->attrnamespace,
          uap->attrname != NULL ? attrname : NULL, td);

      vn_finished_write(mp_writable);
      /*
       * VFS_EXTATTRCTL will have unlocked, but not de-ref'd,
       * filename_vp, so vrele it if it is defined.
       */
      if (filename_vp != NULL)
            vrele(filename_vp);
out:
      VFS_UNLOCK_GIANT(fnvfslocked);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*-
 * Set a named extended attribute on a file or directory
 *
 * Arguments: unlocked vnode "vp", attribute namespace "attrnamespace",
 *            kernelspace string pointer "attrname", userspace buffer
 *            pointer "data", buffer length "nbytes", thread "td".
 * Returns: 0 on success, an error number otherwise
 * Locks: none
 * References: vp must be a valid reference for the duration of the call
 */
static int
extattr_set_vp(struct vnode *vp, int attrnamespace, const char *attrname,
    void *data, size_t nbytes, struct thread *td)
{
      struct mount *mp;
      struct uio auio;
      struct iovec aiov;
      ssize_t cnt;
      int error;

      VFS_ASSERT_GIANT(vp->v_mount);
      error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
      if (error)
            return (error);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);

      aiov.iov_base = data;
      aiov.iov_len = nbytes;
      auio.uio_iov = &aiov;
      auio.uio_iovcnt = 1;
      auio.uio_offset = 0;
      if (nbytes > INT_MAX) {
            error = EINVAL;
            goto done;
      }
      auio.uio_resid = nbytes;
      auio.uio_rw = UIO_WRITE;
      auio.uio_segflg = UIO_USERSPACE;
      auio.uio_td = td;
      cnt = nbytes;

#ifdef MAC
      error = mac_check_vnode_setextattr(td->td_ucred, vp, attrnamespace,
          attrname, &auio);
      if (error)
            goto done;
#endif

      error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio,
          td->td_ucred, td);
      cnt -= auio.uio_resid;
      td->td_retval[0] = cnt;

done:
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
      return (error);
}

int
extattr_set_fd(td, uap)
      struct thread *td;
      struct extattr_set_fd_args /* {
            int fd;
            int attrnamespace;
            const char *attrname;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct file *fp;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      error = getvnode(td->td_proc->p_fd, uap->fd, &fp);
      if (error)
            return (error);

      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
      error = extattr_set_vp(fp->f_vnode, uap->attrnamespace,
          attrname, uap->data, uap->nbytes, td);
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);

      return (error);
}

int
extattr_set_file(td, uap)
      struct thread *td;
      struct extattr_set_file_args /* {
            const char *path;
            int attrnamespace;
            const char *attrname;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct nameidata nd;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_set_vp(nd.ni_vp, uap->attrnamespace, attrname,
          uap->data, uap->nbytes, td);

      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

int
extattr_set_link(td, uap)
      struct thread *td;
      struct extattr_set_link_args /* {
            const char *path;
            int attrnamespace;
            const char *attrname;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct nameidata nd;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      NDINIT(&nd, LOOKUP, MPSAFE | NOFOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_set_vp(nd.ni_vp, uap->attrnamespace, attrname,
          uap->data, uap->nbytes, td);

      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*-
 * Get a named extended attribute on a file or directory
 *
 * Arguments: unlocked vnode "vp", attribute namespace "attrnamespace",
 *            kernelspace string pointer "attrname", userspace buffer
 *            pointer "data", buffer length "nbytes", thread "td".
 * Returns: 0 on success, an error number otherwise
 * Locks: none
 * References: vp must be a valid reference for the duration of the call
 */
static int
extattr_get_vp(struct vnode *vp, int attrnamespace, const char *attrname,
    void *data, size_t nbytes, struct thread *td)
{
      struct uio auio, *auiop;
      struct iovec aiov;
      ssize_t cnt;
      size_t size, *sizep;
      int error;

      VFS_ASSERT_GIANT(vp->v_mount);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_READ);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);

      /*
       * Slightly unusual semantics: if the user provides a NULL data
       * pointer, they don't want to receive the data, just the
       * maximum read length.
       */
      auiop = NULL;
      sizep = NULL;
      cnt = 0;
      if (data != NULL) {
            aiov.iov_base = data;
            aiov.iov_len = nbytes;
            auio.uio_iov = &aiov;
            auio.uio_iovcnt = 1;
            auio.uio_offset = 0;
            if (nbytes > INT_MAX) {
                  error = EINVAL;
                  goto done;
            }
            auio.uio_resid = nbytes;
            auio.uio_rw = UIO_READ;
            auio.uio_segflg = UIO_USERSPACE;
            auio.uio_td = td;
            auiop = &auio;
            cnt = nbytes;
      } else
            sizep = &size;

#ifdef MAC
      error = mac_check_vnode_getextattr(td->td_ucred, vp, attrnamespace,
          attrname, &auio);
      if (error)
            goto done;
#endif

      error = VOP_GETEXTATTR(vp, attrnamespace, attrname, auiop, sizep,
          td->td_ucred, td);

      if (auiop != NULL) {
            cnt -= auio.uio_resid;
            td->td_retval[0] = cnt;
      } else
            td->td_retval[0] = size;

done:
      VOP_UNLOCK(vp, 0, td);
      return (error);
}

int
extattr_get_fd(td, uap)
      struct thread *td;
      struct extattr_get_fd_args /* {
            int fd;
            int attrnamespace;
            const char *attrname;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct file *fp;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      error = getvnode(td->td_proc->p_fd, uap->fd, &fp);
      if (error)
            return (error);

      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
      error = extattr_get_vp(fp->f_vnode, uap->attrnamespace,
          attrname, uap->data, uap->nbytes, td);

      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

int
extattr_get_file(td, uap)
      struct thread *td;
      struct extattr_get_file_args /* {
            const char *path;
            int attrnamespace;
            const char *attrname;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct nameidata nd;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_get_vp(nd.ni_vp, uap->attrnamespace, attrname,
          uap->data, uap->nbytes, td);

      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

int
extattr_get_link(td, uap)
      struct thread *td;
      struct extattr_get_link_args /* {
            const char *path;
            int attrnamespace;
            const char *attrname;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct nameidata nd;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      NDINIT(&nd, LOOKUP, MPSAFE | NOFOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_get_vp(nd.ni_vp, uap->attrnamespace, attrname,
          uap->data, uap->nbytes, td);

      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

/*
 * extattr_delete_vp(): Delete a named extended attribute on a file or
 *                      directory
 *
 * Arguments: unlocked vnode "vp", attribute namespace "attrnamespace",
 *            kernelspace string pointer "attrname", proc "p"
 * Returns: 0 on success, an error number otherwise
 * Locks: none
 * References: vp must be a valid reference for the duration of the call
 */
static int
extattr_delete_vp(struct vnode *vp, int attrnamespace, const char *attrname,
    struct thread *td)
{
      struct mount *mp;
      int error;

      VFS_ASSERT_GIANT(vp->v_mount);
      error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
      if (error)
            return (error);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_WRITE);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);

#ifdef MAC
      error = mac_check_vnode_deleteextattr(td->td_ucred, vp, attrnamespace,
          attrname);
      if (error)
            goto done;
#endif

      error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, td->td_ucred,
          td);
      if (error == EOPNOTSUPP)
            error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
                td->td_ucred, td);
#ifdef MAC
done:
#endif
      VOP_UNLOCK(vp, 0, td);
      vn_finished_write(mp);
      return (error);
}

int
extattr_delete_fd(td, uap)
      struct thread *td;
      struct extattr_delete_fd_args /* {
            int fd;
            int attrnamespace;
            const char *attrname;
      } */ *uap;
{
      struct file *fp;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return (error);
      AUDIT_ARG(text, attrname);

      error = getvnode(td->td_proc->p_fd, uap->fd, &fp);
      if (error)
            return (error);

      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
      error = extattr_delete_vp(fp->f_vnode, uap->attrnamespace,
          attrname, td);
      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

int
extattr_delete_file(td, uap)
      struct thread *td;
      struct extattr_delete_file_args /* {
            const char *path;
            int attrnamespace;
            const char *attrname;
      } */ *uap;
{
      struct nameidata nd;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return(error);
      AUDIT_ARG(text, attrname);

      NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return(error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_delete_vp(nd.ni_vp, uap->attrnamespace, attrname, td);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return(error);
}

int
extattr_delete_link(td, uap)
      struct thread *td;
      struct extattr_delete_link_args /* {
            const char *path;
            int attrnamespace;
            const char *attrname;
      } */ *uap;
{
      struct nameidata nd;
      char attrname[EXTATTR_MAXNAMELEN];
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      error = copyinstr(uap->attrname, attrname, EXTATTR_MAXNAMELEN, NULL);
      if (error)
            return(error);
      AUDIT_ARG(text, attrname);

      NDINIT(&nd, LOOKUP, MPSAFE | NOFOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return(error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_delete_vp(nd.ni_vp, uap->attrnamespace, attrname, td);
      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return(error);
}

/*-
 * Retrieve a list of extended attributes on a file or directory.
 *
 * Arguments: unlocked vnode "vp", attribute namespace 'attrnamespace",
 *            userspace buffer pointer "data", buffer length "nbytes",
 *            thread "td".
 * Returns: 0 on success, an error number otherwise
 * Locks: none
 * References: vp must be a valid reference for the duration of the call
 */
static int
extattr_list_vp(struct vnode *vp, int attrnamespace, void *data,
    size_t nbytes, struct thread *td)
{
      struct uio auio, *auiop;
      size_t size, *sizep;
      struct iovec aiov;
      ssize_t cnt;
      int error;

      VFS_ASSERT_GIANT(vp->v_mount);
      VOP_LEASE(vp, td, td->td_ucred, LEASE_READ);
      vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td);

      auiop = NULL;
      sizep = NULL;
      cnt = 0;
      if (data != NULL) {
            aiov.iov_base = data;
            aiov.iov_len = nbytes;
            auio.uio_iov = &aiov;
            auio.uio_iovcnt = 1;
            auio.uio_offset = 0;
            if (nbytes > INT_MAX) {
                  error = EINVAL;
                  goto done;
            }
            auio.uio_resid = nbytes;
            auio.uio_rw = UIO_READ;
            auio.uio_segflg = UIO_USERSPACE;
            auio.uio_td = td;
            auiop = &auio;
            cnt = nbytes;
      } else
            sizep = &size;

#ifdef MAC
      error = mac_check_vnode_listextattr(td->td_ucred, vp, attrnamespace);
      if (error)
            goto done;
#endif

      error = VOP_LISTEXTATTR(vp, attrnamespace, auiop, sizep,
          td->td_ucred, td);

      if (auiop != NULL) {
            cnt -= auio.uio_resid;
            td->td_retval[0] = cnt;
      } else
            td->td_retval[0] = size;

done:
      VOP_UNLOCK(vp, 0, td);
      return (error);
}


int
extattr_list_fd(td, uap)
      struct thread *td;
      struct extattr_list_fd_args /* {
            int fd;
            int attrnamespace;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct file *fp;
      int vfslocked, error;

      AUDIT_ARG(fd, uap->fd);
      AUDIT_ARG(value, uap->attrnamespace);
      error = getvnode(td->td_proc->p_fd, uap->fd, &fp);
      if (error)
            return (error);

      vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
      error = extattr_list_vp(fp->f_vnode, uap->attrnamespace, uap->data,
          uap->nbytes, td);

      fdrop(fp, td);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

int
extattr_list_file(td, uap)
      struct thread*td;
      struct extattr_list_file_args /* {
            const char *path;
            int attrnamespace;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct nameidata nd;
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      NDINIT(&nd, LOOKUP, MPSAFE | FOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_list_vp(nd.ni_vp, uap->attrnamespace, uap->data,
          uap->nbytes, td);

      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

int
extattr_list_link(td, uap)
      struct thread*td;
      struct extattr_list_link_args /* {
            const char *path;
            int attrnamespace;
            void *data;
            size_t nbytes;
      } */ *uap;
{
      struct nameidata nd;
      int vfslocked, error;

      AUDIT_ARG(value, uap->attrnamespace);
      NDINIT(&nd, LOOKUP, MPSAFE | NOFOLLOW | AUDITVNODE1, UIO_USERSPACE,
          uap->path, td);
      error = namei(&nd);
      if (error)
            return (error);
      NDFREE(&nd, NDF_ONLY_PNBUF);

      vfslocked = NDHASGIANT(&nd);
      error = extattr_list_vp(nd.ni_vp, uap->attrnamespace, uap->data,
          uap->nbytes, td);

      vrele(nd.ni_vp);
      VFS_UNLOCK_GIANT(vfslocked);
      return (error);
}

Generated by  Doxygen 1.6.0   Back to index