freebsd-nq/sys/i386/include/vmparam.h
Alan Cox c5ecbfb410 Avoid the possibility of integer overflow in the calculation of
VM_KMEM_SIZE_MAX.  Specifically, if the user/kernel address space split
was changed such that the kernel address space was greater than or equal
to 2 GB, then overflow would occur.

PR:		161721
MFC after:	3 weeks
2011-12-10 18:42:00 +00:00

205 lines
5.7 KiB
C

/*-
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
* Copyright (c) 1994 John S. Dyson
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* William Jolitz.
*
* 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: @(#)vmparam.h 5.9 (Berkeley) 5/12/91
* $FreeBSD$
*/
#ifndef _MACHINE_VMPARAM_H_
#define _MACHINE_VMPARAM_H_ 1
/*
* Machine dependent constants for 386.
*/
/*
* Virtual memory related constants, all in bytes
*/
#define MAXTSIZ (128UL*1024*1024) /* max text size */
#ifndef DFLDSIZ
#define DFLDSIZ (128UL*1024*1024) /* initial data size limit */
#endif
#ifndef MAXDSIZ
#define MAXDSIZ (512UL*1024*1024) /* max data size */
#endif
#ifndef DFLSSIZ
#define DFLSSIZ (8UL*1024*1024) /* initial stack size limit */
#endif
#ifndef MAXSSIZ
#define MAXSSIZ (64UL*1024*1024) /* max stack size */
#endif
#ifndef SGROWSIZ
#define SGROWSIZ (128UL*1024) /* amount to grow stack */
#endif
/*
* The physical address space is densely populated.
*/
#define VM_PHYSSEG_DENSE
/*
* The number of PHYSSEG entries must be one greater than the number
* of phys_avail entries because the phys_avail entry that spans the
* largest physical address that is accessible by ISA DMA is split
* into two PHYSSEG entries.
*/
#define VM_PHYSSEG_MAX 17
/*
* Create two free page pools. Since the i386 kernel virtual address
* space does not include a mapping onto the machine's entire physical
* memory, VM_FREEPOOL_DIRECT is defined as an alias for the default
* pool, VM_FREEPOOL_DEFAULT.
*/
#define VM_NFREEPOOL 2
#define VM_FREEPOOL_CACHE 1
#define VM_FREEPOOL_DEFAULT 0
#define VM_FREEPOOL_DIRECT 0
/*
* Create two free page lists: VM_FREELIST_DEFAULT is for physical
* pages that are above the largest physical address that is
* accessible by ISA DMA and VM_FREELIST_ISADMA is for physical pages
* that are below that address.
*/
#define VM_NFREELIST 2
#define VM_FREELIST_DEFAULT 0
#define VM_FREELIST_ISADMA 1
/*
* The largest allocation size is 2MB under PAE and 4MB otherwise.
*/
#ifdef PAE
#define VM_NFREEORDER 10
#else
#define VM_NFREEORDER 11
#endif
/*
* Only one memory domain.
*/
#ifndef VM_NDOMAIN
#define VM_NDOMAIN 1
#endif
/*
* Enable superpage reservations: 1 level.
*/
#ifndef VM_NRESERVLEVEL
#define VM_NRESERVLEVEL 1
#endif
/*
* Level 0 reservations consist of 512 pages under PAE and 1024 pages
* otherwise.
*/
#ifndef VM_LEVEL_0_ORDER
#ifdef PAE
#define VM_LEVEL_0_ORDER 9
#else
#define VM_LEVEL_0_ORDER 10
#endif
#endif
/*
* Kernel physical load address.
*/
#ifndef KERNLOAD
#if defined(XEN) && !defined(XEN_PRIVILEGED_GUEST)
#define KERNLOAD 0
#else
#define KERNLOAD (1 << PDRSHIFT)
#endif
#endif /* !defined(KERNLOAD) */
/*
* Virtual addresses of things. Derived from the page directory and
* page table indexes from pmap.h for precision.
* Because of the page that is both a PD and PT, it looks a little
* messy at times, but hey, we'll do anything to save a page :-)
*/
#ifdef XEN
#define VM_MAX_KERNEL_ADDRESS HYPERVISOR_VIRT_START
#else
#define VM_MAX_KERNEL_ADDRESS VADDR(KPTDI+NKPDE-1, NPTEPG-1)
#endif
#define VM_MIN_KERNEL_ADDRESS VADDR(PTDPTDI, PTDPTDI)
#define KERNBASE VADDR(KPTDI, 0)
#define UPT_MAX_ADDRESS VADDR(PTDPTDI, PTDPTDI)
#define UPT_MIN_ADDRESS VADDR(PTDPTDI, 0)
#define VM_MAXUSER_ADDRESS VADDR(PTDPTDI, 0)
#define USRSTACK VM_MAXUSER_ADDRESS
#define VM_MAX_ADDRESS VADDR(PTDPTDI, PTDPTDI)
#define VM_MIN_ADDRESS ((vm_offset_t)0)
/* virtual sizes (bytes) for various kernel submaps */
#ifndef VM_KMEM_SIZE
#define VM_KMEM_SIZE (12 * 1024 * 1024)
#endif
/*
* How many physical pages per KVA page allocated.
* min(max(max(VM_KMEM_SIZE, Physical memory/VM_KMEM_SIZE_SCALE),
* VM_KMEM_SIZE_MIN), VM_KMEM_SIZE_MAX)
* is the total KVA space allocated for kmem_map.
*/
#ifndef VM_KMEM_SIZE_SCALE
#define VM_KMEM_SIZE_SCALE (3)
#endif
/*
* Ceiling on the amount of kmem_map KVA space: 40% of the entire KVA space
* rounded to the nearest multiple of the superpage size.
*/
#ifndef VM_KMEM_SIZE_MAX
#define VM_KMEM_SIZE_MAX (((((VM_MAX_KERNEL_ADDRESS - \
VM_MIN_KERNEL_ADDRESS) >> (PDRSHIFT - 2)) + 5) / 10) << PDRSHIFT)
#endif
/* initial pagein size of beginning of executable file */
#ifndef VM_INITIAL_PAGEIN
#define VM_INITIAL_PAGEIN 16
#endif
#define ZERO_REGION_SIZE (64 * 1024) /* 64KB */
#endif /* _MACHINE_VMPARAM_H_ */