/* $NetBSD: uvm_amap.h,v 1.5 1998/02/10 14:12:04 mrg Exp $ */ /* * XXXCDC: "ROUGH DRAFT" QUALITY UVM PRE-RELEASE FILE! * >>>USE AT YOUR OWN RISK, WORK IS NOT FINISHED<<< */ /* * * Copyright (c) 1997 Charles D. Cranor and Washington University. * All rights reserved. * * 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 and * Washington University. * 4. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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: Id: uvm_amap.h,v 1.1.2.7 1998/01/05 18:12:56 chuck Exp */ #ifndef _UVM_UVM_AMAP_H_ #define _UVM_UVM_AMAP_H_ /* * uvm_amap.h */ /* * defines for handling of large sparce amaps. * * currently the kernel likes to allocate large chunks of VM to reserve * them for possible use. for example, it allocates (reserves) a large * chunk of user VM for possible stack growth. most of the time only * a page or two of this VM is actually used. since the stack is anonymous * memory it makes sense for it to live in an amap, but if we allocated * an amap for the entire stack range we could end up wasting a large * amount of malloc'd KVM. * * for example, on the i386 at boot time we allocate two amaps for the stack * of /sbin/init: * 1. a 7680 slot amap at protection 0 (reserve space for stack) * 2. a 512 slot amap at protection 7 (top of stack) * * most of that VM is never mapped or used. * * to avoid allocating amap resources for the whole range we have the * VM system look for maps that are larger than UVM_AMAP_LARGE slots * (note that 1 slot = 1 vm_page). for maps that are large, we attempt * to break them up into UVM_AMAP_CHUNK slot sized amaps. * * so, in the i386 example, the 7680 slot area is never referenced so * nothing gets allocated. the 512 slot area is referenced, and it * gets divided into 16 slot chunks (hopefully with one 16 slot chunk * being enough to handle the whole stack...). */ #define UVM_AMAP_LARGE 256 /* # of slots in "large" amap */ #define UVM_AMAP_CHUNK 16 /* # of slots to chunk large amaps in */ #ifdef DIAGNOSTIC #define AMAP_B2SLOT(S,B) { \ if ((B) % PAGE_SIZE) \ panic("AMAP_B2SLOT: invalid byte count"); \ (S) = (B) / PAGE_SIZE; \ } #else #define AMAP_B2SLOT(S,B) (S) = (B) / PAGE_SIZE #endif #ifdef VM_AMAP_PPREF #define PPREF_NONE ((int *) -1) #endif /* * handle inline options */ #ifdef UVM_AMAP_INLINE #define AMAP_INLINE static __inline #else #define AMAP_INLINE /* nothing */ #endif /* UVM_AMAP_INLINE */ /* * prototypes: the following prototypes define the interface to amaps */ AMAP_INLINE vm_offset_t amap_add __P((struct vm_aref *, vm_offset_t, struct vm_anon *, int)); struct vm_amap *amap_alloc __P((vm_offset_t, vm_offset_t, int)); void amap_copy __P((vm_map_t, vm_map_entry_t, int, boolean_t, vm_offset_t, vm_offset_t)); void amap_cow_now __P((vm_map_t, vm_map_entry_t)); void amap_extend __P((vm_map_entry_t, vm_size_t)); void amap_free __P((struct vm_amap *)); AMAP_INLINE struct vm_anon *amap_lookup __P((struct vm_aref *, vm_offset_t)); AMAP_INLINE void amap_lookups __P((struct vm_aref *, vm_offset_t, struct vm_anon **, int)); #ifdef VM_AMAP_PPREF void amap_pp_adjref __P((struct vm_amap *, int, vm_size_t, int)); void amap_pp_establish __P((struct vm_amap *)); #endif AMAP_INLINE void amap_ref __P((vm_map_entry_t, int)); void amap_share_protect __P((vm_map_entry_t, vm_prot_t)); void amap_splitref __P((struct vm_aref *, struct vm_aref *, vm_offset_t)); AMAP_INLINE void amap_unadd __P((struct vm_amap *, vm_offset_t)); AMAP_INLINE void amap_unref __P((vm_map_entry_t, int)); void amap_wipeout __P((struct vm_amap *)); #ifdef VM_AMAP_PPREF void amap_wiperange __P((struct vm_amap *, int, int)); #endif struct vm_anon *uvm_analloc __P((void)); void uvm_anfree __P((struct vm_anon *)); void uvm_anon_init __P((void)); void uvm_anon_add __P((int)); struct vm_page *uvm_anon_lockloanpg __P((struct vm_anon *)); #endif /* _UVM_UVM_AMAP_H_ */