NetBSD/sys/uvm/uvm_unix.c

198 lines
5.1 KiB
C

/* $NetBSD: uvm_unix.c,v 1.43 2009/12/15 06:15:11 matt Exp $ */
/*
* Copyright (c) 1997 Charles D. Cranor and Washington University.
* Copyright (c) 1991, 1993 The Regents of the University of California.
* Copyright (c) 1988 University of Utah.
*
* 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 Charles D. Cranor,
* Washington University, 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 $Hdr: vm_unix.c 1.1 89/11/07$
* @(#)vm_unix.c 8.1 (Berkeley) 6/11/93
* from: Id: uvm_unix.c,v 1.1.2.2 1997/08/25 18:52:30 chuck Exp
*/
/*
* uvm_unix.c: traditional sbrk/grow interface to vm.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: uvm_unix.c,v 1.43 2009/12/15 06:15:11 matt Exp $");
#include "opt_pax.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/mount.h>
#include <sys/syscallargs.h>
#ifdef PAX_MPROTECT
#include <sys/pax.h>
#endif /* PAX_MPROTECT */
#include <uvm/uvm.h>
/*
* sys_obreak: set break
*/
int
sys_obreak(struct lwp *l, const struct sys_obreak_args *uap, register_t *retval)
{
/* {
syscallarg(char *) nsize;
} */
struct proc *p = l->l_proc;
struct vmspace *vm = p->p_vmspace;
vaddr_t new, old;
int error;
mutex_enter(&p->p_auxlock);
old = (vaddr_t)vm->vm_daddr;
new = round_page((vaddr_t)SCARG(uap, nsize));
if (new == 0 ||
((new - old) > p->p_rlimit[RLIMIT_DATA].rlim_cur && new > old)) {
mutex_exit(&p->p_auxlock);
return (ENOMEM);
}
old = round_page(old + ptoa(vm->vm_dsize));
if (new == old) {
mutex_exit(&p->p_auxlock);
return (0);
}
/*
* grow or shrink?
*/
if (new > old) {
vm_prot_t prot = UVM_PROT_READ | UVM_PROT_WRITE;
vm_prot_t maxprot = UVM_PROT_ALL;
#ifdef PAX_MPROTECT
pax_mprotect(l, &prot, &maxprot);
#endif /* PAX_MPROTECT */
error = uvm_map(&vm->vm_map, &old, new - old, NULL,
UVM_UNKNOWN_OFFSET, 0,
UVM_MAPFLAG(prot, maxprot,
UVM_INH_COPY,
UVM_ADV_NORMAL, UVM_FLAG_AMAPPAD|UVM_FLAG_FIXED|
UVM_FLAG_OVERLAY|UVM_FLAG_COPYONW));
if (error) {
#ifdef DEBUG
uprintf("sbrk: grow %#"PRIxVADDR" failed, error = %d\n",
new - old, error);
#endif
mutex_exit(&p->p_auxlock);
return (error);
}
vm->vm_dsize += atop(new - old);
} else {
uvm_deallocate(&vm->vm_map, new, old - new);
vm->vm_dsize -= atop(old - new);
}
mutex_exit(&p->p_auxlock);
return (0);
}
/*
* uvm_grow: enlarge the "stack segment" to include sp.
*/
int
uvm_grow(struct proc *p, vaddr_t sp)
{
struct vmspace *vm = p->p_vmspace;
vsize_t nss;
/*
* For user defined stacks (from sendsig).
*/
#ifdef __MACHINE_STACK_GROWS_UP
if (sp < (vaddr_t)vm->vm_minsaddr)
#else
if (sp < (vaddr_t)vm->vm_maxsaddr)
#endif
return (0);
/*
* For common case of already allocated (from trap).
*/
#ifdef __MACHINE_STACK_GROWS_UP
if (sp < USRSTACK + ctob(vm->vm_ssize))
#else
if (sp >= USRSTACK - ctob(vm->vm_ssize))
#endif
return (1);
/*
* Really need to check vs limit and increment stack size if ok.
*/
#ifdef __MACHINE_STACK_GROWS_UP
nss = btoc(sp - USRSTACK);
#else
nss = btoc(USRSTACK - sp);
#endif
if (nss > btoc(p->p_rlimit[RLIMIT_STACK].rlim_cur))
return (0);
vm->vm_ssize = nss;
return (1);
}
/*
* sys_oadvise: old advice system call
*/
/* ARGSUSED */
int
sys_ovadvise(struct lwp *l, const struct sys_ovadvise_args *uap, register_t *retval)
{
#if 0
/* {
syscallarg(int) anom;
} */
#endif
return (EINVAL);
}