NetBSD/sys/vm/vm_unix.c

134 lines
3.9 KiB
C

/*
* Copyright (c) 1988 University of Utah.
* Copyright (c) 1991 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. 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: Utah $Hdr: vm_unix.c 1.1 89/11/07$
*
* from: @(#)vm_unix.c 7.2 (Berkeley) 4/20/91
* $Id: vm_unix.c,v 1.2 1993/05/20 03:59:49 cgd Exp $
*/
/*
* Traditional sbrk/grow interface to VM
*/
#include "param.h"
#include "systm.h"
#include "proc.h"
#include "resourcevar.h"
#include "vm.h"
/* ARGSUSED */
obreak(p, uap, retval)
struct proc *p;
struct args {
char *nsiz;
} *uap;
int *retval;
{
register struct vmspace *vm = p->p_vmspace;
vm_offset_t new, old;
int rv;
register int diff;
old = (vm_offset_t)vm->vm_daddr;
new = round_page(uap->nsiz);
if ((int)(new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur)
return(ENOMEM);
old = round_page(old + ctob(vm->vm_dsize));
diff = new - old;
if (diff > 0) {
rv = vm_allocate(&vm->vm_map, &old, diff, FALSE);
if (rv != KERN_SUCCESS) {
uprintf("sbrk: grow failed, return = %d\n", rv);
return(ENOMEM);
}
vm->vm_dsize += btoc(diff);
} else if (diff < 0) {
diff = -diff;
rv = vm_deallocate(&vm->vm_map, new, diff);
if (rv != KERN_SUCCESS) {
uprintf("sbrk: shrink failed, return = %d\n", rv);
return(ENOMEM);
}
vm->vm_dsize -= btoc(diff);
}
return(0);
}
/*
* Enlarge the "stack segment" to include the specified
* stack pointer for the process.
*/
grow(p, sp)
struct proc *p;
unsigned sp;
{
register struct vmspace *vm = p->p_vmspace;
register int si;
/*
* For user defined stacks (from sendsig).
*/
if (sp < (unsigned)vm->vm_maxsaddr)
return (0);
/*
* For common case of already allocated (from trap).
*/
if (sp >= (unsigned)vm->vm_maxsaddr + MAXSSIZ - ctob(vm->vm_ssize))
return (1);
/*
* Really need to check vs limit and increment stack size if ok.
*/
si = clrnd(btoc(vm->vm_maxsaddr + MAXSSIZ - sp) - vm->vm_ssize);
if (vm->vm_ssize + si > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur))
return (0);
vm->vm_ssize += si;
return (1);
}
/* ARGSUSED */
ovadvise(p, uap, retval)
struct proc *p;
struct args {
int anom;
} *uap;
int *retval;
{
return (EINVAL);
}