freebsd-src/sys/vm/vm_unix.c
2005-01-07 02:29:27 +00:00

177 lines
4.7 KiB
C

/*-
* 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.
* 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
*/
/*
* Traditional sbrk/grow interface to VM
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/proc.h>
#include <sys/resourcevar.h>
#include <sys/sysproto.h>
#include <sys/systm.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#ifndef _SYS_SYSPROTO_H_
struct obreak_args {
char *nsize;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
obreak(td, uap)
struct thread *td;
struct obreak_args *uap;
{
struct vmspace *vm = td->td_proc->p_vmspace;
vm_offset_t new, old, base;
rlim_t datalim, vmemlim;
int rv;
int error = 0;
boolean_t do_map_wirefuture;
PROC_LOCK(td->td_proc);
datalim = lim_cur(td->td_proc, RLIMIT_DATA);
vmemlim = lim_cur(td->td_proc, RLIMIT_VMEM);
PROC_UNLOCK(td->td_proc);
do_map_wirefuture = FALSE;
new = round_page((vm_offset_t)uap->nsize);
vm_map_lock(&vm->vm_map);
base = round_page((vm_offset_t) vm->vm_daddr);
old = base + ctob(vm->vm_dsize);
if (new > base) {
/*
* Check the resource limit, but allow a process to reduce
* its usage, even if it remains over the limit.
*/
if (new - base > datalim && new > old) {
error = ENOMEM;
goto done;
}
if (new > vm_map_max(&vm->vm_map)) {
error = ENOMEM;
goto done;
}
} else if (new < base) {
/*
* This is simply an invalid value. If someone wants to
* do fancy address space manipulations, mmap and munmap
* can do most of what the user would want.
*/
error = EINVAL;
goto done;
}
if (new > old) {
if (vm->vm_map.size + (new - old) > vmemlim) {
error = ENOMEM;
goto done;
}
rv = vm_map_insert(&vm->vm_map, NULL, 0, old, new,
VM_PROT_ALL, VM_PROT_ALL, 0);
if (rv != KERN_SUCCESS) {
error = ENOMEM;
goto done;
}
vm->vm_dsize += btoc(new - old);
/*
* Handle the MAP_WIREFUTURE case for legacy applications,
* by marking the newly mapped range of pages as wired.
* We are not required to perform a corresponding
* vm_map_unwire() before vm_map_delete() below, as
* it will forcibly unwire the pages in the range.
*
* XXX If the pages cannot be wired, no error is returned.
*/
if ((vm->vm_map.flags & MAP_WIREFUTURE) == MAP_WIREFUTURE) {
if (bootverbose)
printf("obreak: MAP_WIREFUTURE set\n");
do_map_wirefuture = TRUE;
}
} else if (new < old) {
rv = vm_map_delete(&vm->vm_map, new, old);
if (rv != KERN_SUCCESS) {
error = ENOMEM;
goto done;
}
vm->vm_dsize -= btoc(old - new);
}
done:
vm_map_unlock(&vm->vm_map);
if (do_map_wirefuture)
(void) vm_map_wire(&vm->vm_map, old, new,
VM_MAP_WIRE_USER|VM_MAP_WIRE_NOHOLES);
return (error);
}
#ifndef _SYS_SYSPROTO_H_
struct ovadvise_args {
int anom;
};
#endif
/*
* MPSAFE
*/
/* ARGSUSED */
int
ovadvise(td, uap)
struct thread *td;
struct ovadvise_args *uap;
{
/* START_GIANT_OPTIONAL */
/* END_GIANT_OPTIONAL */
return (EINVAL);
}