freebsd-nq/sys/vm/vm_unix.c
Alan Cox 3d66f1384e o Remove an incorrect cast from obreak(). This cast would,
for example, break an sbrk(>=4GB) on 64-bit architectures
   even if the resource limit allowed it.
 o Correct an off-by-one error.
 o Correct a spelling error in a comment.
 o Reorder an && expression so that the commonly FALSE expression
   comes first.

Submitted by:	bde (bullets 1 and 2)
2002-06-20 18:38:28 +00:00

149 lines
4.0 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.
* 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 $Hdr: vm_unix.c 1.1 89/11/07$
*
* @(#)vm_unix.c 8.1 (Berkeley) 6/11/93
* $FreeBSD$
*/
/*
* Traditional sbrk/grow interface to VM
*/
#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;
int rv;
int error = 0;
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 > td->td_proc->p_rlimit[RLIMIT_DATA].rlim_cur &&
new > old) {
error = ENOMEM;
goto done;
}
if (new > VM_MAXUSER_ADDRESS) {
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) {
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);
} 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);
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);
}