xref: /src/sys/compat/common/vm_43.c

/*	$NetBSD: vm_43.c,v 1.21 2019/01/27 02:08:39 pgoyette Exp $	*/

/*
 * Copyright (c) 1988 University of Utah.
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * the Systems Programming Group of the University of Utah Computer
 * Science Department.
 *
 * 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. 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: Utah $Hdr: vm_mmap.c 1.6 91/10/21$
 *
 *	@(#)vm_mmap.c	8.5 (Berkeley) 5/19/94
 */

/*
 * Mapped file (mmap) interface to VM
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: vm_43.c,v 1.21 2019/01/27 02:08:39 pgoyette Exp $");

#if defined(_KERNEL_OPT)
#include "opt_compat_netbsd.h"
#endif

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/filedesc.h>
#include <sys/resourcevar.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <sys/file.h>
#include <sys/mman.h>

#include <sys/syscall.h>
#include <sys/syscallvar.h>
#include <sys/syscallargs.h>

#include <miscfs/specfs/specdev.h>

#include <compat/common/compat_mod.h>

static struct syscall_package vm_43_syscalls[] = {
	{ SYS_compat_43_ogetpagesize, 0,
	    (sy_call_t *)compat_43_sys_getpagesize },
	{ SYS_compat_43_ommap, 0, (sy_call_t *)compat_43_sys_mmap },
	{ 0, 0, NULL }
};

/* ARGSUSED */
int
compat_43_sys_getpagesize(struct lwp *l, const void *v, register_t *retval)
{

	*retval = PAGE_SIZE;
	return (0);
}

int
compat_43_sys_mmap(struct lwp *l, const struct compat_43_sys_mmap_args *uap, register_t *retval)
{
	/* {
		syscallarg(void *) addr;
		syscallarg(size_t) len;
		syscallarg(int) prot;
		syscallarg(int) flags;
		syscallarg(int) fd;
		syscallarg(long) pos;
	} */
	struct sys_mmap_args /* {
		syscallarg(void *) addr;
		syscallarg(size_t) len;
		syscallarg(int) prot;
		syscallarg(int) flags;
		syscallarg(int) fd;
		syscallarg(long) pad;
		syscallarg(off_t) pos;
	} */ nargs;
	static const char cvtbsdprot[8] = {
		0,
		PROT_EXEC,
		PROT_WRITE,
		PROT_EXEC|PROT_WRITE,
		PROT_READ,
		PROT_EXEC|PROT_READ,
		PROT_WRITE|PROT_READ,
		PROT_EXEC|PROT_WRITE|PROT_READ,
	};
#define	OMAP_ANON	0x0002
#define	OMAP_COPY	0x0020
#define	OMAP_SHARED	0x0010
#define	OMAP_FIXED	0x0100
#define	OMAP_INHERIT	0x0800

	SCARG(&nargs, addr) = SCARG(uap, addr);
	SCARG(&nargs, len) = SCARG(uap, len);
	/* Note: index using prot is sign-safe due to mask */
	SCARG(&nargs, prot) = cvtbsdprot[SCARG(uap, prot)&0x7];
	SCARG(&nargs, flags) = 0;
	if (SCARG(uap, flags) & OMAP_ANON)
		SCARG(&nargs, flags) |= MAP_ANON;
	if (SCARG(uap, flags) & OMAP_SHARED)
		SCARG(&nargs, flags) |= MAP_SHARED;
	else
		SCARG(&nargs, flags) |= MAP_PRIVATE;
	if (SCARG(uap, flags) & OMAP_COPY) {
		SCARG(&nargs, flags) |= MAP_PRIVATE;
#if defined(COMPAT_10) && defined(__i386__)
		/*
		 * Ancient kernel on x86 did not obey PROT_EXEC on i386 at least
		 * and ld.so did not turn it on. We take care of this on amd64
		 * in compat32.
		 */
		SCARG(&nargs, prot) |= PROT_EXEC;
#endif
	}
	if (SCARG(uap, flags) & OMAP_FIXED)
		SCARG(&nargs, flags) |= MAP_FIXED;
	if (SCARG(uap, flags) & OMAP_INHERIT)
		SCARG(&nargs, flags) |= MAP_INHERIT;
	SCARG(&nargs, fd) = SCARG(uap, fd);
	SCARG(&nargs, pos) = SCARG(uap, pos);
	return (sys_mmap(l, &nargs, retval));
}

int
vm_43_init(void)
{

	return syscall_establish(NULL, vm_43_syscalls);
}

int
vm_43_fini(void)
{

	return syscall_disestablish(NULL, vm_43_syscalls);
}