added my responsibility for the `cpm' port

[unix-history] / sys / kern / vfs_syscalls.c

/*
* Copyright (c) 1989 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
*    must display the following acknowledgement:
*      This product includes software developed by the University of
*      California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
*    may be used to endorse or promote products derived from this software
*    without specific prior written permission.
*
* 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.
*
*      from: @(#)vfs_syscalls.c        7.74 (Berkeley) 6/21/91
*      $Id: vfs_syscalls.c,v 1.16 1994/05/26 04:46:47 ache Exp $
*/

#include "param.h"
#include "systm.h"
#include "namei.h"
#include "filedesc.h"
#include "kernel.h"
#include "file.h"
#include "stat.h"
#include "vnode.h"
#include "mount.h"
#include "proc.h"
#include "uio.h"
#include "malloc.h"

static int getvnode(struct filedesc *, int, struct file **);
static int chdirec(struct nameidata *, struct proc *);

/*
* Virtual File System System Calls
*/

/*
* Mount system call.
*/

struct mount_args {
       int     type;
       char    *dir;
       int     flags;
       caddr_t data;
};

/* ARGSUSED */
int
mount(p, uap, retval)
       struct proc *p;
       register struct mount_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       register struct mount *mp;
       int error, flag = 0;
       struct nameidata nd;

       /*
        * Must be super user
        */
       if (error = suser(p->p_ucred, &p->p_acflag))
               return (error);
       /*
        * Get vnode to be covered
        */
       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->dir;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (uap->flags & MNT_UPDATE) {
               if ((vp->v_flag & VROOT) == 0) {
                       vput(vp);
                       return (EINVAL);
               }
               mp = vp->v_mount;
               /*
                * We allow going from read-only to read-write,
                * but not from read-write to read-only.
                */
               if ((mp->mnt_flag & MNT_RDONLY) == 0 &&
                   (uap->flags & MNT_RDONLY) != 0) {
                       vput(vp);
                       return (EOPNOTSUPP);    /* Needs translation */
               }
               flag = mp->mnt_flag;
               mp->mnt_flag |= MNT_UPDATE;
               VOP_UNLOCK(vp);
               goto update;
       }
       vinvalbuf(vp, 1);
       if (vp->v_usecount != 1) {
               vput(vp);
               return (EBUSY);
       }
       if (vp->v_type != VDIR) {
               vput(vp);
               return (ENOTDIR);
       }
       if ((unsigned long)uap->type > MOUNT_MAXTYPE ||
           vfssw[uap->type] == (struct vfsops *)0) {
               vput(vp);
               return (ENODEV);
       }

       /*
        * Allocate and initialize the file system.
        */
       mp = (struct mount *)malloc((u_long)sizeof(struct mount),
               M_MOUNT, M_WAITOK);
       mp->mnt_op = vfssw[uap->type];
       mp->mnt_flag = 0;
       mp->mnt_exroot = 0;
       mp->mnt_mounth = NULLVP;
       if (error = vfs_lock(mp)) {
               free((caddr_t)mp, M_MOUNT);
               vput(vp);
               return (error);
       }
       if (vp->v_mountedhere != (struct mount *)0) {
               vfs_unlock(mp);
               free((caddr_t)mp, M_MOUNT);
               vput(vp);
               return (EBUSY);
       }
       vp->v_mountedhere = mp;
       mp->mnt_vnodecovered = vp;
update:
       /*
        * Set the mount level flags.
        */
       mp->mnt_flag &=
               ~(MNT_RDONLY|MNT_NOSUID|MNT_NOEXEC|MNT_NODEV|MNT_SYNCHRONOUS);
       mp->mnt_flag |= uap->flags &
               (MNT_RDONLY|MNT_NOSUID|MNT_NOEXEC|MNT_NODEV|MNT_SYNCHRONOUS);
       /*
        * Mount the filesystem.
        */
       error = VFS_MOUNT(mp, uap->dir, uap->data, ndp, p);
       if (mp->mnt_flag & MNT_UPDATE) {
               mp->mnt_flag &= ~MNT_UPDATE;
               vrele(vp);
               if (error)
                       mp->mnt_flag = flag;
               return (error);
       }
       /*
        * Put the new filesystem on the mount list after root.
        */
       mp->mnt_next = rootfs->mnt_next;
       mp->mnt_prev = rootfs;
       rootfs->mnt_next = mp;
       mp->mnt_next->mnt_prev = mp;
       cache_purge(vp);
       if (!error) {
               VOP_UNLOCK(vp);
               vfs_unlock(mp);
               error = VFS_START(mp, 0, p);
       } else {
               vfs_remove(mp);
               free((caddr_t)mp, M_MOUNT);
               vput(vp);
       }
       return (error);
}

/*
* Unmount system call.
*
* Note: unmount takes a path to the vnode mounted on as argument,
* not special file (as before).
*/

struct umount_args {
       char    *pathp;
       int     flags;
};

/* ARGSUSED */
int
unmount(p, uap, retval)
       struct proc *p;
       register struct umount_args *uap;
       int *retval;
{
       register struct vnode *vp;
       register struct nameidata *ndp;
       struct mount *mp;
       int error;
       struct nameidata nd;

       /*
        * Must be super user
        */
       if (error = suser(p->p_ucred, &p->p_acflag))
               return (error);

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | LOCKLEAF | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->pathp;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       /*
        * Must be the root of the filesystem
        */
       if ((vp->v_flag & VROOT) == 0) {
               vput(vp);
               return (EINVAL);
       }
       mp = vp->v_mount;
       vput(vp);
       return (dounmount(mp, uap->flags, p));
}

/*
* Do an unmount.
*/
int
dounmount(mp, flags, p)
       register struct mount *mp;
       int flags;
       struct proc *p;
{
       struct vnode *coveredvp;
       int error;

       coveredvp = mp->mnt_vnodecovered;
       if (vfs_busy(mp))
               return (EBUSY);
       mp->mnt_flag |= MNT_UNMOUNT;
       if (error = vfs_lock(mp))
               return (error);

       vnode_pager_umount(mp); /* release cached vnodes */
       cache_purgevfs(mp);     /* remove cache entries for this file sys */
       if ((error = VFS_SYNC(mp, MNT_WAIT)) == 0 || (flags & MNT_FORCE))
               error = VFS_UNMOUNT(mp, flags, p);
       mp->mnt_flag &= ~MNT_UNMOUNT;
       vfs_unbusy(mp);
       if (error) {
               vfs_unlock(mp);
       } else {
               vrele(coveredvp);
               vfs_remove(mp);
               free((caddr_t)mp, M_MOUNT);
       }
       return (error);
}

/*
* Sync system call.
* Sync each mounted filesystem.
*/
/* ARGSUSED */
int
sync(p, uap, retval)
       struct proc *p;
       void *uap;
       int *retval;
{
       register struct mount *mp;
       struct mount *omp;

       if ((mp = rootfs) == NULL)
               return (0);
       do {
               /*
                * The lock check below is to avoid races with mount
                * and unmount.
                */
               if ((mp->mnt_flag & (MNT_MLOCK|MNT_RDONLY|MNT_MPBUSY)) == 0 &&
                   !vfs_busy(mp)) {
                       VFS_SYNC(mp, MNT_NOWAIT);
                       omp = mp;
                       mp = mp->mnt_next;
                       vfs_unbusy(omp);
               } else
                       mp = mp->mnt_next;
       } while (mp != rootfs);
       return (0);
}

/*
* Operate on filesystem quotas.
*/

struct quotactl_args {
       char *path;
       int cmd;
       int uid;
       caddr_t arg;
};

/* ARGSUSED */
int
quotactl(p, uap, retval)
       struct proc *p;
       register struct quotactl_args *uap;
       int *retval;
{
       register struct mount *mp;
       register struct nameidata *ndp;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->path;
       if (error = namei(ndp, p))
               return (error);
       mp = ndp->ni_vp->v_mount;
       vrele(ndp->ni_vp);
       return (VFS_QUOTACTL(mp, uap->cmd, uap->uid, uap->arg, p));
}

/*
* Get filesystem statistics.
*/

struct statfs_args {
       char *path;
       struct statfs *buf;
};

/* ARGSUSED */
int
statfs(p, uap, retval)
       struct proc *p;
       register struct statfs_args *uap;
       int *retval;
{
       register struct mount *mp;
       register struct nameidata *ndp;
       register struct statfs *sp;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->path;
       if (error = namei(ndp, p))
               return (error);
       mp = ndp->ni_vp->v_mount;
       sp = &mp->mnt_stat;
       vrele(ndp->ni_vp);
       if (error = VFS_STATFS(mp, sp, p))
               return (error);
       sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
       return (copyout((caddr_t)sp, (caddr_t)uap->buf, sizeof(*sp)));
}

/*
* Get filesystem statistics.
*/

struct fstatfs_args {
       int fd;
       struct statfs *buf;
};

/* ARGSUSED */
int
fstatfs(p, uap, retval)
       struct proc *p;
       register struct fstatfs_args *uap;
       int *retval;
{
       struct file *fp;
       struct mount *mp;
       register struct statfs *sp;
       int error;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       mp = ((struct vnode *)fp->f_data)->v_mount;
       sp = &mp->mnt_stat;
       if (error = VFS_STATFS(mp, sp, p))
               return (error);
       sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
       return (copyout((caddr_t)sp, (caddr_t)uap->buf, sizeof(*sp)));
}

/*
* Get statistics on all filesystems.
*/

struct getfsstat_args {
       struct statfs *buf;
       long bufsize;
       int flags;
};

int
getfsstat(p, uap, retval)
       struct proc *p;
       register struct getfsstat_args *uap;
       int *retval;
{
       register struct mount *mp;
       register struct statfs *sp;
       caddr_t sfsp;
       long count, maxcount, error;

       maxcount = uap->bufsize / sizeof(struct statfs);
       sfsp = (caddr_t)uap->buf;
       mp = rootfs;
       count = 0;
       do {
               if (sfsp && count < maxcount &&
                   ((mp->mnt_flag & MNT_MLOCK) == 0)) {
                       sp = &mp->mnt_stat;
                       /*
                        * If MNT_NOWAIT is specified, do not refresh the
                        * fsstat cache. MNT_WAIT overrides MNT_NOWAIT.
                        */
                       if (((uap->flags & MNT_NOWAIT) == 0 ||
                           (uap->flags & MNT_WAIT)) &&
                           (error = VFS_STATFS(mp, sp, p))) {
                               mp = mp->mnt_prev;
                               continue;
                       }
                       sp->f_flags = mp->mnt_flag & MNT_VISFLAGMASK;
                       if (error = copyout((caddr_t)sp, sfsp, sizeof(*sp)))
                               return (error);
                       sfsp += sizeof(*sp);
               }
               count++;
               mp = mp->mnt_prev;
       } while (mp != rootfs);
       if (sfsp && count > maxcount)
               *retval = maxcount;
       else
               *retval = count;
       return (0);
}

/*
* Change current working directory to a given file descriptor.
*/

struct fchdir_args {
       int     fd;
};

/* ARGSUSED */
int
fchdir(p, uap, retval)
       struct proc *p;
       struct fchdir_args *uap;
       int *retval;
{
       register struct filedesc *fdp = p->p_fd;
       register struct vnode *vp;
       struct file *fp;
       int error;

       if (error = getvnode(fdp, uap->fd, &fp))
               return (error);
       vp = (struct vnode *)fp->f_data;
       VOP_LOCK(vp);
       if (vp->v_type != VDIR)
               error = ENOTDIR;
       else
               error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p);
       VOP_UNLOCK(vp);
       if (error)
               return (error);
       VREF(vp);
       vrele(fdp->fd_cdir);
       fdp->fd_cdir = vp;
       return (0);
}

/*
* Change current working directory (``.'').
*/

struct chdir_args {
       char    *fname;
};

/* ARGSUSED */
int
chdir(p, uap, retval)
       struct proc *p;
       struct chdir_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct filedesc *fdp = p->p_fd;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = chdirec(ndp, p))
               return (error);
       vrele(fdp->fd_cdir);
       fdp->fd_cdir = ndp->ni_vp;
       return (0);
}

/*
* Change notion of root (``/'') directory.
*/

struct chroot_args {
       char    *fname;
};

/* ARGSUSED */
int
chroot(p, uap, retval)
       struct proc *p;
       struct chroot_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct filedesc *fdp = p->p_fd;
       int error;
       struct nameidata nd;

       if (error = suser(p->p_ucred, &p->p_acflag))
               return (error);
       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = chdirec(ndp, p))
               return (error);
       if (fdp->fd_rdir != NULL)
               vrele(fdp->fd_rdir);
       fdp->fd_rdir = ndp->ni_vp;
       return (0);
}

/*
* Common routine for chroot and chdir.
*/
static int
chdirec(ndp, p)
       struct nameidata *ndp;
       struct proc *p;
{
       struct vnode *vp;
       int error;

       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type != VDIR)
               error = ENOTDIR;
       else
               error = VOP_ACCESS(vp, VEXEC, p->p_ucred, p);
       VOP_UNLOCK(vp);
       if (error)
               vrele(vp);
       return (error);
}

/*
* Open system call.
* Check permissions, allocate an open file structure,
* and call the device open routine if any.
*/

struct open_args {
       char    *fname;
       int     mode;
       int     crtmode;
};

int
open(p, uap, retval)
       struct proc *p;
       register struct open_args *uap;
       int *retval;
{
       struct nameidata *ndp;
       register struct filedesc *fdp = p->p_fd;
       register struct file *fp;
       register struct vnode *vp;
       int fmode, cmode;
       struct file *nfp;
       int type, indx, error;
       struct flock lf;
       struct nameidata nd;
       extern struct fileops vnops;

       if (error = falloc(p, &nfp, &indx))
               return (error);
       fp = nfp;
       fmode = FFLAGS(uap->mode);
       cmode = ((uap->crtmode &~ fdp->fd_cmask) & 07777) &~ S_ISVTX;
       ndp = &nd;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       p->p_dupfd = -indx - 1;                 /* XXX check for fdopen */
       if (error = vn_open(ndp, p, fmode, cmode)) {
               ffree(fp);
               if (error == ENODEV &&          /* XXX from fdopen */
                   ((short) p->p_dupfd) >= 0 &&
                   (error = dupfdopen(fdp, indx, p->p_dupfd, fmode)) == 0) {
                       *retval = indx;
                       return (0);
               }
               if (error == ERESTART)
                       error = EINTR;
               fdp->fd_ofiles[indx] = NULL;
               return (error);
       }
       vp = ndp->ni_vp;
       VOP_UNLOCK(vp);
       fp->f_flag = fmode & FMASK;
       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;
               if (error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type)) {
                       (void) vn_close(vp, fp->f_flag, fp->f_cred, p);
                       ffree(fp);
                       fdp->fd_ofiles[indx] = NULL;
                       return (error);
               }
               fp->f_flag |= FHASLOCK;
       }
       fp->f_type = DTYPE_VNODE;
       fp->f_ops = &vnops;
       fp->f_data = (caddr_t)vp;
       *retval = indx;
       return (0);
}

#ifdef COMPAT_43
/*
* Creat system call.
*/

struct ocreat_args {
       char    *fname;
       int     fmode;
};

int
ocreat(p, uap, retval)
       struct proc *p;
       register struct ocreat_args *uap;
       int *retval;
{
       struct newargs {
               char    *fname;
               int     mode;
               int     crtmode;
       } openuap;

       openuap.fname = uap->fname;
       openuap.crtmode = uap->fmode;
       openuap.mode = O_WRONLY | O_CREAT | O_TRUNC;
       return (open(p, (struct args *)&openuap, retval));
}
#endif /* COMPAT_43 */

/*
* Mknod system call.
*/

struct mknod_args {
       char    *fname;
       int     fmode;
       int     dev;
};

/* ARGSUSED */
int
mknod(p, uap, retval)
       struct proc *p;
       register struct mknod_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       if (error = suser(p->p_ucred, &p->p_acflag))
               return (error);
       ndp = &nd;
       ndp->ni_nameiop = CREATE | LOCKPARENT;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp != NULL) {
               error = EEXIST;
               goto out;
       }
       VATTR_NULL(&vattr);
       switch (uap->fmode & 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;
       default:
               error = EINVAL;
               goto out;
       }
       vattr.va_mode = (uap->fmode & 07777) &~ p->p_fd->fd_cmask;
       vattr.va_rdev = uap->dev;
out:
       if (!error) {
               error = VOP_MKNOD(ndp, &vattr, p->p_ucred, p);
       } else {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               if (vp)
                       vrele(vp);
       }
       return (error);
}

/*
* Mkfifo system call.
*/

struct mkfifo_args {
       char    *fname;
       int     fmode;
};

/* ARGSUSED */
int
mkfifo(p, uap, retval)
       struct proc *p;
       register struct mkfifo_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

#ifndef FIFO
       return (EOPNOTSUPP);
#else
       ndp = &nd;
       ndp->ni_nameiop = CREATE | LOCKPARENT;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       if (ndp->ni_vp != NULL) {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == ndp->ni_vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               vrele(ndp->ni_vp);
               return (EEXIST);
       }
       VATTR_NULL(&vattr);
       vattr.va_type = VFIFO;
       vattr.va_mode = (uap->fmode & 07777) &~ p->p_fd->fd_cmask;
       return (VOP_MKNOD(ndp, &vattr, p->p_ucred, p));
#endif /* FIFO */
}

/*
* Link system call.
*/

struct link_args {
       char    *target;
       char    *linkname;
};

/* ARGSUSED */
int
link(p, uap, retval)
       struct proc *p;
       register struct link_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp, *xp;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->target;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type == VDIR) {
               error = EPERM;
               goto out1;
       }
       ndp->ni_nameiop = CREATE | LOCKPARENT;
       ndp->ni_dirp = (caddr_t)uap->linkname;
       if (error = namei(ndp, p))
               goto out1;
       xp = ndp->ni_vp;
       if (xp != NULL) {
               error = EEXIST;
               goto out;
       }
       xp = ndp->ni_dvp;
       if (vp->v_mount != xp->v_mount)
               error = EXDEV;
out:
       if (!error) {
               error = VOP_LINK(vp, ndp, p);
       } else {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == ndp->ni_vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               if (ndp->ni_vp)
                       vrele(ndp->ni_vp);
       }
out1:
       vrele(vp);
       return (error);
}

/*
* Make a symbolic link.
*/

struct symlink_args {
       char    *target;
       char    *linkname;
};

/* ARGSUSED */
int
symlink(p, uap, retval)
       struct proc *p;
       register struct symlink_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       struct vattr vattr;
       char *target;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->linkname;
       MALLOC(target, char *, MAXPATHLEN, M_NAMEI, M_WAITOK);
       if (error = copyinstr(uap->target, target, MAXPATHLEN, (u_int *)0))
               goto out;
       ndp->ni_nameiop = CREATE | LOCKPARENT;
       if (error = namei(ndp, p))
               goto out;
       if (ndp->ni_vp) {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == ndp->ni_vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               vrele(ndp->ni_vp);
               error = EEXIST;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_mode = 0777 &~ p->p_fd->fd_cmask;
       error = VOP_SYMLINK(ndp, &vattr, target, p);
out:
       FREE(target, M_NAMEI);
       return (error);
}

/*
* Delete a name from the filesystem.
*/

struct unlink_args {
       char    *fname;
};

/* ARGSUSED */
int
unlink(p, uap, retval)
       struct proc *p;
       struct unlink_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = DELETE | LOCKPARENT | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type == VDIR &&
           (error = suser(p->p_ucred, &p->p_acflag)))
               goto out;
       /*
        * The root of a mounted filesystem cannot be deleted.
        */
       if (vp->v_flag & VROOT) {
               error = EBUSY;
               goto out;
       }
       (void) vnode_pager_uncache(vp);
out:
       if (!error) {
               error = VOP_REMOVE(ndp, p);
       } else {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               vput(vp);
       }
       return (error);
}

/*
* Seek system call.
*/

struct lseek_args {
       int     fdes;
       off_t   off;
       int     sbase;
};

int
lseek(p, uap, retval)
       struct proc *p;
       register struct lseek_args *uap;
       off_t *retval;
{
       struct ucred *cred = p->p_ucred;
       register struct filedesc *fdp = p->p_fd;
       register struct file *fp;
       struct vattr vattr;
       int error;

       if ((unsigned)uap->fdes >= fdp->fd_nfiles ||
           (fp = fdp->fd_ofiles[uap->fdes]) == NULL)
               return (EBADF);
       if (fp->f_type != DTYPE_VNODE)
               return (ESPIPE);
       switch (uap->sbase) {

       case L_INCR:
               fp->f_offset += uap->off;
               break;

       case L_XTND:
               if (error = VOP_GETATTR((struct vnode *)fp->f_data,
                   &vattr, cred, p))
                       return (error);
               fp->f_offset = uap->off + vattr.va_size;
               break;

       case L_SET:
               fp->f_offset = uap->off;
               break;

       default:
               return (EINVAL);
       }
       *retval = fp->f_offset;
       return (0);
}

/*
* Check access permissions.
*/

struct saccess_args {
       char    *fname;
       int     fmode;
};

/* ARGSUSED */
int
saccess(p, uap, retval)
       struct proc *p;
       register struct saccess_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct ucred *cred = p->p_ucred;
       register struct vnode *vp;
       int error, mode, svuid, svgid;
       struct nameidata nd;

       ndp = &nd;
       svuid = cred->cr_uid;
       svgid = cred->cr_groups[0];
       cred->cr_uid = p->p_cred->p_ruid;
       cred->cr_groups[0] = p->p_cred->p_rgid;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               goto out1;
       vp = ndp->ni_vp;
       /*
        * fmode == 0 means only check for exist
        */
       if (uap->fmode) {
               mode = 0;
               if (uap->fmode & R_OK)
                       mode |= VREAD;
               if (uap->fmode & W_OK)
                       mode |= VWRITE;
               if (uap->fmode & X_OK)
                       mode |= VEXEC;
               if ((mode & VWRITE) == 0 || (error = vn_writechk(vp)) == 0)
                       error = VOP_ACCESS(vp, mode, cred, p);
       }
       vput(vp);
out1:
       cred->cr_uid = svuid;
       cred->cr_groups[0] = svgid;
       return (error);
}

/*
* Stat system call.
* This version follows links.
*/

struct stat_args {
       char    *fname;
       struct stat *ub;
};

/* ARGSUSED */
int
stat(p, uap, retval)
       struct proc *p;
       register struct stat_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       struct stat sb;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | LOCKLEAF | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       error = vn_stat(ndp->ni_vp, &sb, p);
       vput(ndp->ni_vp);
       if (error)
               return (error);
       error = copyout((caddr_t)&sb, (caddr_t)uap->ub, sizeof (sb));
       return (error);
}

/*
* Lstat system call.
* This version does not follow links.
*/

struct lstat_args {
       char    *fname;
       struct stat *ub;
};

/* ARGSUSED */
int
lstat(p, uap, retval)
       struct proc *p;
       register struct lstat_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       struct stat sb;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | LOCKLEAF | NOFOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       error = vn_stat(ndp->ni_vp, &sb, p);
       vput(ndp->ni_vp);
       if (error)
               return (error);
       error = copyout((caddr_t)&sb, (caddr_t)uap->ub, sizeof (sb));
       return (error);
}

/*
* Return target name of a symbolic link.
*/

struct readlink_args {
       char    *name;
       char    *buf;
       int     count;
};

/* ARGSUSED */
int
readlink(p, uap, retval)
       struct proc *p;
       register struct readlink_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct iovec aiov;
       struct uio auio;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->name;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type != VLNK) {
               error = EINVAL;
               goto out;
       }
       aiov.iov_base = uap->buf;
       aiov.iov_len = uap->count;
       auio.uio_iov = &aiov;
       auio.uio_iovcnt = 1;
       auio.uio_offset = 0;
       auio.uio_rw = UIO_READ;
       auio.uio_segflg = UIO_USERSPACE;
       auio.uio_procp = p;
       auio.uio_resid = uap->count;
       error = VOP_READLINK(vp, &auio, p->p_ucred);
out:
       vput(vp);
       *retval = uap->count - auio.uio_resid;
       return (error);
}

/*
* Change flags of a file given path name.
*/

struct chflags_args {
       char    *fname;
       int     flags;
};

/* ARGSUSED */
int
chflags(p, uap, retval)
       struct proc *p;
       register struct chflags_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_flags = uap->flags;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       vput(vp);
       return (error);
}

/*
* Change flags of a file given a file descriptor.
*/

struct fdchflags_args {
       int     fd;
       int     flags;
};

/* ARGSUSED */
int
fchflags(p, uap, retval)
       struct proc *p;
       register struct fdchflags_args *uap;
       int *retval;
{
       struct vattr vattr;
       struct vnode *vp;
       struct file *fp;
       int error;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       vp = (struct vnode *)fp->f_data;
       VOP_LOCK(vp);
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_flags = uap->flags;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       VOP_UNLOCK(vp);
       return (error);
}

/*
* Change mode of a file given path name.
*/

struct chmod_args {
       char    *fname;
       int     fmode;
};

/* ARGSUSED */
int
chmod(p, uap, retval)
       struct proc *p;
       register struct chmod_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_mode = uap->fmode & 07777;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       vput(vp);
       return (error);
}

/*
* Change mode of a file given a file descriptor.
*/

struct fchmod_args {
       int     fd;
       int     fmode;
};

/* ARGSUSED */
int
fchmod(p, uap, retval)
       struct proc *p;
       register struct fchmod_args *uap;
       int *retval;
{
       struct vattr vattr;
       struct vnode *vp;
       struct file *fp;
       int error;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       vp = (struct vnode *)fp->f_data;
       VOP_LOCK(vp);
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_mode = uap->fmode & 07777;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       VOP_UNLOCK(vp);
       return (error);
}

/*
* Set ownership given a path name.
*/

struct chown_args {
       char    *fname;
       int     uid;
       int     gid;
};

/* ARGSUSED */
int
chown(p, uap, retval)
       struct proc *p;
       register struct chown_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | NOFOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_uid = uap->uid;
       vattr.va_gid = uap->gid;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       vput(vp);
       return (error);
}

/*
* Set ownership given a file descriptor.
*/

struct fchown_args {
       int     fd;
       int     uid;
       int     gid;
};

/* ARGSUSED */
int
fchown(p, uap, retval)
       struct proc *p;
       register struct fchown_args *uap;
       int *retval;
{
       struct vattr vattr;
       struct vnode *vp;
       struct file *fp;
       int error;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       vp = (struct vnode *)fp->f_data;
       VOP_LOCK(vp);
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       VATTR_NULL(&vattr);
       vattr.va_uid = uap->uid;
       vattr.va_gid = uap->gid;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       VOP_UNLOCK(vp);
       return (error);
}

/*
* Set the access and modification times of a file.
*/

struct utimes_args {
       char    *fname;
       struct  timeval *tptr;
};

/* ARGSUSED */
int
utimes(p, uap, retval)
       struct proc *p;
       register struct utimes_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct timeval tv[2];
       struct vattr vattr;
       int error;
       struct nameidata nd;

       VATTR_NULL(&vattr);
       if ((caddr_t)uap->tptr == NULL) {
               microtime(&tv[0]);
               tv[1] = tv[0];
               vattr.va_vaflags |= VA_UTIMES_NULL;
       } else if (error = copyin((caddr_t)uap->tptr, (caddr_t)tv, sizeof (tv)))
               return (error);
       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_mount->mnt_flag & MNT_RDONLY) {
               error = EROFS;
               goto out;
       }
       vattr.va_atime = tv[0];
       vattr.va_mtime = tv[1];
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       vput(vp);
       return (error);
}

/*
* Truncate a file given its path name.
*/

struct truncate_args {
       char    *fname;
       off_t   length;
};

/* ARGSUSED */
int
truncate(p, uap, retval)
       struct proc *p;
       register struct truncate_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type == VDIR) {
               error = EISDIR;
               goto out;
       }
       if ((error = vn_writechk(vp)) ||
           (error = VOP_ACCESS(vp, VWRITE, p->p_ucred, p)))
               goto out;
       VATTR_NULL(&vattr);
       vattr.va_size = uap->length;
       error = VOP_SETATTR(vp, &vattr, p->p_ucred, p);
out:
       vput(vp);
       return (error);
}

/*
* Truncate a file given a file descriptor.
*/

struct ftruncate_args {
       int     fd;
       off_t   length;
};

/* ARGSUSED */
int
ftruncate(p, uap, retval)
       struct proc *p;
       register struct ftruncate_args *uap;
       int *retval;
{
       struct vattr vattr;
       struct vnode *vp;
       struct file *fp;
       int error;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       if ((fp->f_flag & FWRITE) == 0)
               return (EINVAL);
       vp = (struct vnode *)fp->f_data;
       VOP_LOCK(vp);
       if (vp->v_type == VDIR) {
               error = EISDIR;
               goto out;
       }
       if (error = vn_writechk(vp))
               goto out;
       VATTR_NULL(&vattr);
       vattr.va_size = uap->length;
       error = VOP_SETATTR(vp, &vattr, fp->f_cred, p);
out:
       VOP_UNLOCK(vp);
       return (error);
}

/*
* Synch an open file.
*/

struct fsync_args {
       int     fd;
};

/* ARGSUSED */
int
fsync(p, uap, retval)
       struct proc *p;
       struct fsync_args *uap;
       int *retval;
{
       register struct vnode *vp;
       struct file *fp;
       int error;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       vp = (struct vnode *)fp->f_data;
       VOP_LOCK(vp);
       error = VOP_FSYNC(vp, fp->f_flag, fp->f_cred, MNT_WAIT, p);
       VOP_UNLOCK(vp);
       return (error);
}

/*
* Rename system call.
*
* Source and destination must either both be directories, or both
* not be directories.  If target is a directory, it must be empty.
*/

struct rename_args {
       char    *from;
       char    *to;
};

/* ARGSUSED */
int
rename(p, uap, retval)
       struct proc *p;
       register struct rename_args *uap;
       int *retval;
{
       register struct vnode *tvp, *fvp, *tdvp;
       struct nameidata fromnd, tond;
       int error;

       fromnd.ni_nameiop = DELETE | WANTPARENT | SAVESTART;
       fromnd.ni_segflg = UIO_USERSPACE;
       fromnd.ni_dirp = uap->from;
       if (error = namei(&fromnd, p))
               return (error);
       fvp = fromnd.ni_vp;
       tond.ni_nameiop = RENAME | LOCKPARENT | LOCKLEAF | NOCACHE | SAVESTART;
       tond.ni_segflg = UIO_USERSPACE;
       tond.ni_dirp = uap->to;
       if (error = namei(&tond, p)) {
               VOP_ABORTOP(&fromnd);
               vrele(fromnd.ni_dvp);
               vrele(fvp);
               goto out1;
       }
       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->v_mount != tvp->v_mount) {
                       error = EXDEV;
                       goto out;
               }
       }
       if (fvp->v_mount != tdvp->v_mount) {
               error = EXDEV;
               goto out;
       }
       if (fvp == tdvp)
               error = EINVAL;
       /*
        * If source is the same as the destination (that is the
        * same inode number with the same name in the same directory),
        * then there is nothing to do.
        */
       if (fvp == tvp && fromnd.ni_dvp == tdvp &&
           fromnd.ni_namelen == tond.ni_namelen &&
           !bcmp(fromnd.ni_ptr, tond.ni_ptr, fromnd.ni_namelen))
               error = -1;
out:
       if (!error) {
               error = VOP_RENAME(&fromnd, &tond, p);
       } else {
               VOP_ABORTOP(&tond);
               if (tdvp == tvp)
                       vrele(tdvp);
               else
                       vput(tdvp);
               if (tvp)
                       vput(tvp);
               VOP_ABORTOP(&fromnd);
               vrele(fromnd.ni_dvp);
               vrele(fvp);
       }
       vrele(tond.ni_startdir);
       FREE(tond.ni_pnbuf, M_NAMEI);
out1:
       if (fromnd.ni_startdir)
               vrele(fromnd.ni_startdir);
       FREE(fromnd.ni_pnbuf, M_NAMEI);
       if (error == -1)
               return (0);
       return (error);
}

/*
* Mkdir system call.
*/

struct mkdir_args {
       char    *name;
       int     dmode;
};

/* ARGSUSED */
int
mkdir(p, uap, retval)
       struct proc *p;
       register struct mkdir_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = CREATE | LOCKPARENT;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->name;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp != NULL) {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               vrele(vp);
               return (EEXIST);
       }
       VATTR_NULL(&vattr);
       vattr.va_type = VDIR;
       vattr.va_mode = (uap->dmode & 0777) &~ p->p_fd->fd_cmask;
       error = VOP_MKDIR(ndp, &vattr, p);
       if (!error)
               vput(ndp->ni_vp);
       return (error);
}

/*
* Rmdir system call.
*/

struct rmdir_args {
       char    *name;
};

/* ARGSUSED */
int
rmdir(p, uap, retval)
       struct proc *p;
       struct rmdir_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = DELETE | LOCKPARENT | LOCKLEAF;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->name;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type != VDIR) {
               error = ENOTDIR;
               goto out;
       }
       /*
        * No rmdir "." please.
        */
       if (ndp->ni_dvp == vp) {
               error = EINVAL;
               goto out;
       }
       /*
        * The root of a mounted filesystem cannot be deleted.
        */
       if (vp->v_flag & VROOT)
               error = EBUSY;
out:
       if (!error) {
               error = VOP_RMDIR(ndp, p);
       } else {
               VOP_ABORTOP(ndp);
               if (ndp->ni_dvp == vp)
                       vrele(ndp->ni_dvp);
               else
                       vput(ndp->ni_dvp);
               vput(vp);
       }
       return (error);
}

/*
* Read a block of directory entries in a file system independent format.
*/

struct getdirentries_args {
       int     fd;
       char    *buf;
       unsigned count;
       long    *basep;
};

int
getdirentries(p, uap, retval)
       struct proc *p;
       register struct getdirentries_args *uap;
       int *retval;
{
       register struct vnode *vp;
       struct file *fp;
       struct uio auio;
       struct iovec aiov;
       off_t off;
       int error, eofflag;

       if (error = getvnode(p->p_fd, uap->fd, &fp))
               return (error);
       if ((fp->f_flag & FREAD) == 0)
               return (EBADF);
       vp = (struct vnode *)fp->f_data;
       if (vp->v_type != VDIR)
               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_procp = p;
       auio.uio_resid = uap->count;
       VOP_LOCK(vp);
       auio.uio_offset = off = fp->f_offset;
       error = VOP_READDIR(vp, &auio, fp->f_cred, &eofflag);
       fp->f_offset = auio.uio_offset;
       VOP_UNLOCK(vp);
       if (error)
               return (error);
       error = copyout((caddr_t)&off, (caddr_t)uap->basep, sizeof(long));
       *retval = uap->count - auio.uio_resid;
       return (error);
}

/*
* Set the mode mask for creation of filesystem nodes.
*/

struct umask_args {
       int     mask;
};

mode_t
umask(p, uap, retval)
       struct proc *p;
       struct umask_args *uap;
       int *retval;
{
       register struct filedesc *fdp = p->p_fd;

       *retval = fdp->fd_cmask;
       fdp->fd_cmask = uap->mask & 07777;
       return (0);
}

/*
* Void all references to file by ripping underlying filesystem
* away from vnode.
*/

struct revoke_args {
       char    *fname;
};

/* ARGSUSED */
int
revoke(p, uap, retval)
       struct proc *p;
       register struct revoke_args *uap;
       int *retval;
{
       register struct nameidata *ndp;
       register struct vnode *vp;
       struct vattr vattr;
       int error;
       struct nameidata nd;

       ndp = &nd;
       ndp->ni_nameiop = LOOKUP | FOLLOW;
       ndp->ni_segflg = UIO_USERSPACE;
       ndp->ni_dirp = uap->fname;
       if (error = namei(ndp, p))
               return (error);
       vp = ndp->ni_vp;
       if (vp->v_type != VCHR && vp->v_type != VBLK) {
               error = EINVAL;
               goto out;
       }
       if (error = VOP_GETATTR(vp, &vattr, p->p_ucred, p))
               goto out;
       if (p->p_ucred->cr_uid != vattr.va_uid &&
           (error = suser(p->p_ucred, &p->p_acflag)))
               goto out;
       if (vp->v_usecount > 1 || (vp->v_flag & VALIASED))
               vgoneall(vp);
out:
       vrele(vp);
       return (error);
}

/*
* Convert a user file descriptor to a kernel file entry.
*/
static int
getvnode(fdp, fdes, fpp)
       struct filedesc *fdp;
       int fdes;
       struct file **fpp;
{
       struct file *fp;

       if ((unsigned)fdes >= fdp->fd_nfiles ||
           (fp = fdp->fd_ofiles[fdes]) == NULL)
               return (EBADF);
       if (fp->f_type != DTYPE_VNODE)
               return (EINVAL);
       *fpp = fp;
       return (0);
}