vm_unix.c revision 43638 
1/*
2 * Copyright (c) 1988 University of Utah.
3 * Copyright (c) 1991, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * the Systems Programming Group of the University of Utah Computer
8 * Science Department.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *	This product includes software developed by the University of
21 *	California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
23 *    may be used to endorse or promote products derived from this software
24 *    without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36 * SUCH DAMAGE.
37 *
38 * from: Utah $Hdr: vm_unix.c 1.1 89/11/07$
39 *
40 *	@(#)vm_unix.c	8.1 (Berkeley) 6/11/93
41 * $Id: vm_unix.c,v 1.17 1998/10/13 08:24:44 dg Exp $
42 */
43
44/*
45 * Traditional sbrk/grow interface to VM
46 */
47#include <sys/param.h>
48#include <sys/sysproto.h>
49#include <sys/proc.h>
50#include <sys/resourcevar.h>
51
52#include <vm/vm.h>
53#include <vm/vm_param.h>
54#include <sys/lock.h>
55#include <vm/pmap.h>
56#include <vm/vm_map.h>
57#include <vm/swap_pager.h>
58#include <vm/vm_prot.h>
59
60#ifndef _SYS_SYSPROTO_H_
61struct obreak_args {
62	char *nsize;
63};
64#endif
65
66/* ARGSUSED */
67int
68obreak(p, uap)
69	struct proc *p;
70	struct obreak_args *uap;
71{
72	register struct vmspace *vm = p->p_vmspace;
73	vm_offset_t new, old, base;
74	int rv;
75
76	base = round_page((vm_offset_t) vm->vm_daddr);
77	new = round_page((vm_offset_t)uap->nsize);
78	if (new > base) {
79		if ((new - base) > (unsigned) p->p_rlimit[RLIMIT_DATA].rlim_cur)
80			return ENOMEM;
81		if (new >= VM_MAXUSER_ADDRESS)
82			return (ENOMEM);
83	} else if (new < base) {
84		/*
85		 * This is simply an invalid value.  If someone wants to
86		 * do fancy address space manipulations, mmap and munmap
87		 * can do most of what the user would want.
88		 */
89		return EINVAL;
90	}
91
92	old = base + ctob(vm->vm_dsize);
93
94	if (new > old) {
95		vm_size_t diff;
96		if (swap_pager_full) {
97			return (ENOMEM);
98		}
99		diff = new - old;
100		rv = vm_map_find(&vm->vm_map, NULL, 0, &old, diff, FALSE,
101			VM_PROT_READ|VM_PROT_WRITE, VM_PROT_ALL, 0);
102		if (rv != KERN_SUCCESS) {
103			return (ENOMEM);
104		}
105		vm->vm_dsize += btoc(diff);
106	} else if (new < old) {
107		rv = vm_map_remove(&vm->vm_map, new, old);
108		if (rv != KERN_SUCCESS) {
109			return (ENOMEM);
110		}
111		vm->vm_dsize -= btoc(old - new);
112	}
113	return (0);
114}
115
116#ifndef _SYS_SYSPROTO_H_
117struct ovadvise_args {
118	int anom;
119};
120#endif
121
122/* ARGSUSED */
123int
124ovadvise(p, uap)
125	struct proc *p;
126	struct ovadvise_args *uap;
127{
128
129	return (EINVAL);
130}
131