text: /*	$OpenBSD: linux_file.c,v 1.9 1997/11/13 06:37:48 deraadt Exp $	*/
  /*	$NetBSD: linux_file.c,v 1.15 1996/05/20 01:59:09 fvdl Exp $	*/
  
  /*
   * Copyright (c) 1995 Frank van der Linden
   * 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 for the NetBSD Project
   *      by Frank van der Linden
   * 4. The name of the author may not be used to endorse or promote products
   *    derived from this software without specific prior written permission
   *
   * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include <sys/param.h>
  #include <sys/systm.h>
  #include <sys/namei.h>
  #include <sys/proc.h>
  #include <sys/file.h>
  #include <sys/stat.h>
  #include <sys/filedesc.h>
  #include <sys/ioctl.h>
  #include <sys/kernel.h>
  #include <sys/mount.h>
  #include <sys/malloc.h>
  #include <sys/vnode.h>
  #include <sys/tty.h>
  #include <sys/conf.h>
  
  #include <sys/syscallargs.h>
  
  #include <compat/linux/linux_types.h>
  #include <compat/linux/linux_signal.h>
  #include <compat/linux/linux_syscallargs.h>
  #include <compat/linux/linux_fcntl.h>
  #include <compat/linux/linux_util.h>
  
  #include <machine/linux_machdep.h>
  
  static int linux_to_bsd_ioflags __P((int));
  static int bsd_to_linux_ioflags __P((int));
  static void bsd_to_linux_flock __P((struct flock *, struct linux_flock *));
  static void linux_to_bsd_flock __P((struct linux_flock *, struct flock *));
  static void bsd_to_linux_stat __P((struct stat *, struct linux_stat *));
  static int linux_stat1 __P((struct proc *, void *, register_t *, int));
  
  /*
   * Some file-related calls are handled here. The usual flag conversion
   * an structure conversion is done, and alternate emul path searching.
   */
  
  /*
   * The next two functions convert between the Linux and NetBSD values
   * of the flags used in open(2) and fcntl(2).
   */
  static int
  linux_to_bsd_ioflags(lflags)
  	int lflags;
  {
  	int res = 0;
  
  	res |= cvtto_bsd_mask(lflags, LINUX_O_WRONLY, O_WRONLY);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_RDONLY, O_RDONLY);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_RDWR, O_RDWR);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_CREAT, O_CREAT);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_EXCL, O_EXCL);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_NOCTTY, O_NOCTTY);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_TRUNC, O_TRUNC);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_NDELAY, O_NDELAY);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_SYNC, O_FSYNC);
  	res |= cvtto_bsd_mask(lflags, LINUX_FASYNC, O_ASYNC);
  	res |= cvtto_bsd_mask(lflags, LINUX_O_APPEND, O_APPEND);
  
  	return res;
  }
  
  static int
  bsd_to_linux_ioflags(bflags)
  	int bflags;
  {
  	int res = 0;
  
  	res |= cvtto_linux_mask(bflags, O_WRONLY, LINUX_O_WRONLY);
  	res |= cvtto_linux_mask(bflags, O_RDONLY, LINUX_O_RDONLY);
  	res |= cvtto_linux_mask(bflags, O_RDWR, LINUX_O_RDWR);
  	res |= cvtto_linux_mask(bflags, O_CREAT, LINUX_O_CREAT);
  	res |= cvtto_linux_mask(bflags, O_EXCL, LINUX_O_EXCL);
  	res |= cvtto_linux_mask(bflags, O_NOCTTY, LINUX_O_NOCTTY);
  	res |= cvtto_linux_mask(bflags, O_TRUNC, LINUX_O_TRUNC);
  	res |= cvtto_linux_mask(bflags, O_NDELAY, LINUX_O_NDELAY);
  	res |= cvtto_linux_mask(bflags, O_FSYNC, LINUX_O_SYNC);
  	res |= cvtto_linux_mask(bflags, O_ASYNC, LINUX_FASYNC);
  	res |= cvtto_linux_mask(bflags, O_APPEND, LINUX_O_APPEND);
  
  	return res;
  }
  
  /*
   * creat(2) is an obsolete function, but it's present as a Linux
   * system call, so let's deal with it.
   *
   * Just call open(2) with the TRUNC, CREAT and WRONLY flags.
   */
  int
  linux_sys_creat(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_creat_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) mode;
  	} */ *uap = v;
  	struct sys_open_args oa;
  	caddr_t sg;
  
  	sg = stackgap_init(p->p_emul);
  	LINUX_CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
  
  	SCARG(&oa, path) = SCARG(uap, path);
  	SCARG(&oa, flags) = O_CREAT | O_TRUNC | O_WRONLY;
  	SCARG(&oa, mode) = SCARG(uap, mode);
  
  	return sys_open(p, &oa, retval);
  }
  
  /*
   * open(2). Take care of the different flag values, and let the
   * NetBSD syscall do the real work. See if this operation
   * gives the current process a controlling terminal.
   * (XXX is this necessary?)
   */
  int
  linux_sys_open(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_open_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) flags;
  		syscallarg(int) mode;
  	} */ *uap = v;
  	int error, fl;
  	struct sys_open_args boa;
  	caddr_t sg;
  
  	sg = stackgap_init(p->p_emul);
  
  	fl = linux_to_bsd_ioflags(SCARG(uap, flags));
  
  	if (fl & O_CREAT)
  		LINUX_CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
  	else
  		LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	SCARG(&boa, path) = SCARG(uap, path);
  	SCARG(&boa, flags) = fl;
  	SCARG(&boa, mode) = SCARG(uap, mode);
  
  	if ((error = sys_open(p, &boa, retval)))
  		return error;
  
  	/*
  	 * this bit from sunos_misc.c (and svr4_fcntl.c).
  	 * If we are a session leader, and we don't have a controlling
  	 * terminal yet, and the O_NOCTTY flag is not set, try to make
  	 * this the controlling terminal.
  	 */ 
          if (!(fl & O_NOCTTY) && SESS_LEADER(p) && !(p->p_flag & P_CONTROLT)) {
                  struct filedesc *fdp = p->p_fd;
                  struct file     *fp = fdp->fd_ofiles[*retval];
  
                  /* ignore any error, just give it a try */
                  if (fp->f_type == DTYPE_VNODE)
                          (fp->f_ops->fo_ioctl) (fp, TIOCSCTTY, (caddr_t) 0, p);
          }
  	return 0;
  }
  
  /*
   * This appears to be part of a Linux attempt to switch to 64 bits file sizes.
   */
  int
  linux_sys_llseek(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_llseek_args /* {
  		syscallarg(int) fd;
  		syscallarg(uint32_t) ohigh;
  		syscallarg(uint32_t) olow;
  		syscallarg(caddr_t) res;
  		syscallarg(int) whence;
  	} */ *uap = v;
  	struct sys_lseek_args bla;
  	int error;
  	off_t off;
  
  	off = SCARG(uap, olow) | (((off_t) SCARG(uap, ohigh)) << 32);
  
  	SCARG(&bla, fd) = SCARG(uap, fd);
  	SCARG(&bla, offset) = off;
  	SCARG(&bla, whence) = SCARG(uap, whence);
  
  	if ((error = sys_lseek(p, &bla, retval)))
  		return error;
  
  	if ((error = copyout(retval, SCARG(uap, res), sizeof (off_t))))
  		return error;
  
  	retval[0] = 0;
  	return 0;
  }
  
  /*
   * The next two functions take care of converting the flock
   * structure back and forth between Linux and NetBSD format.
   * The only difference in the structures is the order of
   * the fields, and the 'whence' value.
   */
  static void
  bsd_to_linux_flock(bfp, lfp)
  	struct flock *bfp;
  	struct linux_flock *lfp;
  {
  
  	lfp->l_start = bfp->l_start;
  	lfp->l_len = bfp->l_len;
  	lfp->l_pid = bfp->l_pid;
  	lfp->l_whence = bfp->l_whence;
  	switch (bfp->l_type) {
  	case F_RDLCK:
  		lfp->l_type = LINUX_F_RDLCK;
  		break;
  	case F_UNLCK:
  		lfp->l_type = LINUX_F_UNLCK;
  		break;
  	case F_WRLCK:
  		lfp->l_type = LINUX_F_WRLCK;
  		break;
  	}
  }
  
  static void
  linux_to_bsd_flock(lfp, bfp)
  	struct linux_flock *lfp;
  	struct flock *bfp;
  {
  
  	bfp->l_start = lfp->l_start;
  	bfp->l_len = lfp->l_len;
  	bfp->l_pid = lfp->l_pid;
  	bfp->l_whence = lfp->l_whence;
  	switch (lfp->l_type) {
  	case LINUX_F_RDLCK:
  		bfp->l_type = F_RDLCK;
  		break;
  	case LINUX_F_UNLCK:
  		bfp->l_type = F_UNLCK;
  		break;
  	case LINUX_F_WRLCK:
  		bfp->l_type = F_WRLCK;
  		break;
  	}
  }
  
  /*
   * Most actions in the fcntl() call are straightforward; simply
   * pass control to the NetBSD system call. A few commands need
   * conversions after the actual system call has done its work,
   * because the flag values and lock structure are different.
   */
  int
  linux_sys_fcntl(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_fcntl_args /* {
  		syscallarg(int) fd;
  		syscallarg(int) cmd;
  		syscallarg(void *) arg;
  	} */ *uap = v;
  	int fd, cmd, error, val;
  	caddr_t arg, sg;
  	struct linux_flock lfl;
  	struct flock *bfp, bfl;
  	struct sys_fcntl_args fca;
  	struct filedesc *fdp;
  	struct file *fp;
  	struct vnode *vp;
  	struct vattr va;
  	long pgid;
  	struct pgrp *pgrp;
  	struct tty *tp, *(*d_tty) __P((dev_t));
  
  	fd = SCARG(uap, fd);
  	cmd = SCARG(uap, cmd);
  	arg = (caddr_t) SCARG(uap, arg);
  
  	switch (cmd) {
  	case LINUX_F_DUPFD:
  		cmd = F_DUPFD;
  		break;
  	case LINUX_F_GETFD:
  		cmd = F_GETFD;
  		break;
  	case LINUX_F_SETFD:
  		cmd = F_SETFD;
  		break;
  	case LINUX_F_GETFL:
  		SCARG(&fca, fd) = fd;
  		SCARG(&fca, cmd) = F_GETFL;
  		SCARG(&fca, arg) = arg;
  		if ((error = sys_fcntl(p, &fca, retval)))
  			return error;
  		retval[0] = bsd_to_linux_ioflags(retval[0]);
  		return 0;
  	case LINUX_F_SETFL:
  		val = linux_to_bsd_ioflags((int)SCARG(uap, arg));
  		SCARG(&fca, fd) = fd;
  		SCARG(&fca, cmd) = F_SETFL;
  		SCARG(&fca, arg) = (caddr_t) val;
  		return sys_fcntl(p, &fca, retval);
  	case LINUX_F_GETLK:
  		sg = stackgap_init(p->p_emul);
  		if ((error = copyin(arg, &lfl, sizeof lfl)))
  			return error;
  		linux_to_bsd_flock(&lfl, &bfl);
  		bfp = (struct flock *) stackgap_alloc(&sg, sizeof *bfp);
  		SCARG(&fca, fd) = fd;
  		SCARG(&fca, cmd) = F_GETLK;
  		SCARG(&fca, arg) = bfp;
  		if ((error = copyout(&bfl, bfp, sizeof bfl)))
  			return error;
  		if ((error = sys_fcntl(p, &fca, retval)))
  			return error;
  		if ((error = copyin(bfp, &bfl, sizeof bfl)))
  			return error;
  		bsd_to_linux_flock(&bfl, &lfl);
  		error = copyout(&lfl, arg, sizeof lfl);
  		return error;
  		break;
  	case LINUX_F_SETLK:
  	case LINUX_F_SETLKW:
  		cmd = (cmd == LINUX_F_SETLK ? F_SETLK : F_SETLKW);
  		if ((error = copyin(arg, &lfl, sizeof lfl)))
  			return error;
  		linux_to_bsd_flock(&lfl, &bfl);
  		sg = stackgap_init(p->p_emul);
  		bfp = (struct flock *) stackgap_alloc(&sg, sizeof *bfp);
  		if ((error = copyout(&bfl, bfp, sizeof bfl)))
  			return error;
  		SCARG(&fca, fd) = fd;
  		SCARG(&fca, cmd) = cmd;
  		SCARG(&fca, arg) = bfp;
  		return sys_fcntl(p, &fca, retval);
  		break;
  	case LINUX_F_SETOWN:
  	case LINUX_F_GETOWN:	
  		/*
  		 * We need to route around the normal fcntl() for these calls,
  		 * since it uses TIOC{G,S}PGRP, which is too restrictive for
  		 * Linux F_{G,S}ETOWN semantics. For sockets, this problem
  		 * does not exist.
  		 */
  		fdp = p->p_fd;
  		if ((u_int)fd >= fdp->fd_nfiles ||
  		    (fp = fdp->fd_ofiles[fd]) == NULL)
  			return EBADF;
  		if (fp->f_type == DTYPE_SOCKET) {
  			cmd = cmd == LINUX_F_SETOWN ? F_SETOWN : F_GETOWN;
  			break;
  		}
  		vp = (struct vnode *)fp->f_data;
  		if (vp->v_type != VCHR)
  			return EINVAL;
  		if ((error = VOP_GETATTR(vp, &va, p->p_ucred, p)))
  			return error;
  		d_tty = cdevsw[major(va.va_rdev)].d_tty;
  		if (!d_tty || (!(tp = (*d_tty)(va.va_rdev))))
  			return EINVAL;
  		if (cmd == LINUX_F_GETOWN) {
  			retval[0] = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID;
  			return 0;
  		}
  		if ((long)arg <= 0) {
  			pgid = -(long)arg;
  		} else {
  			struct proc *p1 = pfind((long)arg);
  			if (p1 == 0)
  				return (ESRCH);
  			pgid = (long)p1->p_pgrp->pg_id;
  		}
  		pgrp = pgfind(pgid);
  		if (pgrp == NULL || pgrp->pg_session != p->p_session)
  			return EPERM;
  		tp->t_pgrp = pgrp;
  		return 0;
  	default:
  		return EOPNOTSUPP;
  	}
  
  	SCARG(&fca, fd) = fd;
  	SCARG(&fca, cmd) = cmd;
  	SCARG(&fca, arg) = arg;
  
  	return sys_fcntl(p, &fca, retval);
  }
  
  /*
   * Convert a NetBSD stat structure to a Linux stat structure.
   * Only the order of the fields and the padding in the structure
   * is different. linux_fakedev is a machine-dependent function
   * which optionally converts device driver major/minor numbers
   * (XXX horrible, but what can you do against code that compares
   * things against constant major device numbers? sigh)
   */
  static void
  bsd_to_linux_stat(bsp, lsp)
  	struct stat *bsp;
  	struct linux_stat *lsp;
  {
  
  	lsp->lst_dev     = bsp->st_dev;
  	lsp->lst_ino     = bsp->st_ino;
  	lsp->lst_mode    = bsp->st_mode;
  	lsp->lst_nlink   = bsp->st_nlink;
  	lsp->lst_uid     = bsp->st_uid;
  	lsp->lst_gid     = bsp->st_gid;
  	lsp->lst_rdev    = linux_fakedev(bsp->st_rdev);
  	lsp->lst_size    = bsp->st_size;
  	lsp->lst_blksize = bsp->st_blksize;
  	lsp->lst_blocks  = bsp->st_blocks;
  	lsp->lst_atime   = bsp->st_atime;
  	lsp->lst_mtime   = bsp->st_mtime;
  	lsp->lst_ctime   = bsp->st_ctime;
  }
  
  /*
   * The stat functions below are plain sailing. stat and lstat are handled
   * by one function to avoid code duplication.
   */
  int
  linux_sys_fstat(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_fstat_args /* {
  		syscallarg(int) fd;
  		syscallarg(linux_stat *) sp;
  	} */ *uap = v;
  	struct sys_fstat_args fsa;
  	struct linux_stat tmplst;
  	struct stat *st,tmpst;
  	caddr_t sg;
  	int error;
  
  	sg = stackgap_init(p->p_emul);
  
  	st = stackgap_alloc(&sg, sizeof (struct stat));
  
  	SCARG(&fsa, fd) = SCARG(uap, fd);
  	SCARG(&fsa, sb) = st;
  
  	if ((error = sys_fstat(p, &fsa, retval)))
  		return error;
  
  	if ((error = copyin(st, &tmpst, sizeof tmpst)))
  		return error;
  
  	bsd_to_linux_stat(&tmpst, &tmplst);
  
  	if ((error = copyout(&tmplst, SCARG(uap, sp), sizeof tmplst)))
  		return error;
  
  	return 0;
  }
  
  static int
  linux_stat1(p, v, retval, dolstat)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  	int dolstat;
  {
  	struct sys_stat_args sa;
  	struct linux_stat tmplst;
  	struct stat *st, tmpst;
  	caddr_t sg;
  	int error;
  	struct linux_sys_stat_args *uap = v;
  
  	sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	st = stackgap_alloc(&sg, sizeof (struct stat));
  	SCARG(&sa, ub) = st;
  	SCARG(&sa, path) = SCARG(uap, path);
  
  	if ((error = (dolstat ? sys_lstat(p, &sa, retval) :
  				sys_stat(p, &sa, retval))))
  		return error;
  
  	if ((error = copyin(st, &tmpst, sizeof tmpst)))
  		return error;
  
  	bsd_to_linux_stat(&tmpst, &tmplst);
  
  	if ((error = copyout(&tmplst, SCARG(uap, sp), sizeof tmplst)))
  		return error;
  
  	return 0;
  }
  
  int
  linux_sys_stat(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_stat_args /* {
  		syscallarg(char *) path;
  		syscallarg(struct linux_stat *) sp;
  	} */ *uap = v;
  
  	return linux_stat1(p, uap, retval, 0);
  }
  
  int
  linux_sys_lstat(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_lstat_args /* {
  		syscallarg(char *) path;
  		syscallarg(struct linux_stat *) sp;
  	} */ *uap = v;
  
  	return linux_stat1(p, uap, retval, 1);
  }
  
  /*
   * The following syscalls are mostly here because of the alternate path check.
   */
  int
  linux_sys_access(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_access_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) flags;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	return sys_access(p, uap, retval);
  }
  
  int
  linux_sys_unlink(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  
  {
  	struct linux_sys_unlink_args /* {
  		syscallarg(char *) path;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	return sys_unlink(p, uap, retval);
  }
  
  int
  linux_sys_chdir(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_chdir_args /* {
  		syscallarg(char *) path;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	return sys_chdir(p, uap, retval);
  }
  
  int
  linux_sys_mknod(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_mknod_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) mode;
  		syscallarg(int) dev;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  	struct sys_mkfifo_args bma;
  
  	LINUX_CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
  
  	/*
  	 * BSD handles FIFOs seperately
  	 */
  	if (SCARG(uap, mode) & S_IFIFO) {
  		SCARG(&bma, path) = SCARG(uap, path);
  		SCARG(&bma, mode) = SCARG(uap, mode);
  		return sys_mkfifo(p, uap, retval);
  	} else
  		return sys_mknod(p, uap, retval);
  }
  
  int
  linux_sys_chmod(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_chmod_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) mode;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	return sys_chmod(p, uap, retval);
  }
  
  int
  linux_sys_chown(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_chown_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) uid;
  		syscallarg(int) gid;
  	} */ *uap = v;
  	struct sys_chown_args bca;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	SCARG(&bca, path) = SCARG(uap, path);
  	SCARG(&bca, uid) = ((linux_uid_t)SCARG(uap, uid) == (linux_uid_t)-1) ?
  		(uid_t)-1 : SCARG(uap, uid);
  	SCARG(&bca, gid) = ((linux_gid_t)SCARG(uap, gid) == (linux_gid_t)-1) ?
  		(gid_t)-1 : SCARG(uap, gid);
  	
  	return sys_chown(p, &bca, retval);
  }
  
  int
  linux_sys_fchown(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_fchown_args /* {
  		syscallarg(int) fd;
  		syscallarg(int) uid;
  		syscallarg(int) gid;
  	} */ *uap = v;
  	struct sys_fchown_args bfa;
  
  	SCARG(&bfa, fd) = SCARG(uap, fd);
  	SCARG(&bfa, uid) = ((linux_uid_t)SCARG(uap, uid) == (linux_uid_t)-1) ?
  		(uid_t)-1 : SCARG(uap, uid);
  	SCARG(&bfa, gid) = ((linux_gid_t)SCARG(uap, gid) == (linux_gid_t)-1) ?
  		(gid_t)-1 : SCARG(uap, gid);
  	
  	return sys_fchown(p, &bfa, retval);
  }
  
  int
  linux_sys_rename(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_rename_args /* {
  		syscallarg(char *) from;
  		syscallarg(char *) to;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, from));
  	LINUX_CHECK_ALT_CREAT(p, &sg, SCARG(uap, to));
  
  	return sys_rename(p, uap, retval);
  }
  
  int
  linux_sys_mkdir(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_mkdir_args /* {
  		syscallarg(char *) path;
  		syscallarg(int) mode;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_CREAT(p, &sg, SCARG(uap, path));
  
  	return sys_mkdir(p, uap, retval);
  }
  
  int
  linux_sys_rmdir(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_rmdir_args /* {
  		syscallarg(char *) path;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	return sys_rmdir(p, uap, retval);
  }
  
  int
  linux_sys_symlink(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_symlink_args /* {
  		syscallarg(char *) path;
  		syscallarg(char *) to;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  	LINUX_CHECK_ALT_CREAT(p, &sg, SCARG(uap, to));
  
  	return sys_symlink(p, uap, retval);
  }
  
  int
  linux_sys_readlink(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_readlink_args /* {
  		syscallarg(char *) name;
  		syscallarg(char *) buf;
  		syscallarg(int) count;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, name));
  
  	return sys_readlink(p, uap, retval);
  }
  
  int
  linux_sys_truncate(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_truncate_args /* {
  		syscallarg(char *) path;
  		syscallarg(long) length;
  	} */ *uap = v;
  	caddr_t sg = stackgap_init(p->p_emul);
  
  	LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
  
  	return compat_43_sys_truncate(p, uap, retval);
  }
  
  /*
   * This is just fsync() for now (just as it is in the Linux kernel)
   */
  int
  linux_sys_fdatasync(p, v, retval)
  	struct proc *p;
  	void *v;
  	register_t *retval;
  {
  	struct linux_sys_fdatasync_args /* {
  		syscallarg(int) fd;
  	} */ *uap = v;
  	return sys_fsync(p, uap, retval);
  }
  