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emacs/mps/code/vmw3.c
Richard Brooksby 4009b8a559 Abolishing eventgen.pl. event structures are now expanded by the preprocessor.
Abolishing event formats.  Each event now has its own structure.
Event parameters are now written directly into the event buffer, rather than being copied twice.

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 Change: 179010
 ServerID: perforce.ravenbrook.com
2012-08-21 22:48:11 +01:00

312 lines
8.5 KiB
C

/* vmw3.c: VIRTUAL MEMORY MAPPING FOR WIN32
*
* $Id$
* Copyright (c) 2001 Ravenbrook Limited. See end of file for license.
*
* .design: See <design/vm/>.
*
* .purpose: This is the implementation of the virtual memory mapping
* interface (vm.h) for Win32s.
*
* The documentation for Win32 used is the "Win32 Programmer's Reference"
* provided with Microsoft Visual C++ 2.0.
*
* VirtualAlloc is used to reserve address space and to "commit" (map)
* address ranges onto storage. VirtualFree is used to release and
* "decommit" (unmap) pages. These functions are documented in the
* Win32 SDK help, under System Services/Memory Management.
*
* .assume.free.success: We assume that VirtualFree will never return
* an error; this is because we always pass in legal parameters
* (hopefully).
*
* .assume.not-last: We assume that VirtualAlloc will never return
* a block of memory that occupies the last page in memory, so
* that limit is representable and bigger than base.
*
* .assume.lpvoid-addr: We assume that the windows type LPVOID and
* the MM type Addr are assignment-compatible.
*
* .assume.sysalign: We assume that the page size on the system
* is a power of two.
*
* Notes
* 1. GetSystemInfo returns a thing called szAllocationGranularity
* the purpose of which is unclear but which might affect the
* reservation of address space. Experimentally, it does not.
* Microsoft's documentation is extremely unclear on this point.
* richard 1995-02-15
*/
#include "mpm.h"
#ifndef MPS_OS_W3
#error "vmw3.c is Win32 specific, but MPS_OS_W3 is not set"
#endif
#ifdef VM_RM
#error "vmw3.c compiled with VM_RM set"
#endif
#include "mpswin.h"
SRCID(vmw3, "$Id$");
/* VMStruct -- virtual memory structure */
#define VMSig ((Sig)0x519B3999) /* SIGnature VM */
typedef struct VMStruct {
Sig sig; /* <design/sig/> */
Align align; /* page size */
Addr base, limit; /* boundaries of reserved space */
Size reserved; /* total reserved address space */
Size mapped; /* total mapped memory */
} VMStruct;
/* VMAlign -- return the page size */
Align VMAlign(VM vm)
{
AVERT(VM, vm);
return vm->align;
}
/* VMCheck -- check a VM structure */
Bool VMCheck(VM vm)
{
CHECKS(VM, vm);
CHECKL(vm->base != 0);
CHECKL(vm->limit != 0);
CHECKL(vm->base < vm->limit);
CHECKL(vm->mapped <= vm->reserved);
CHECKL(AddrIsAligned(vm->base, vm->align));
CHECKL(AddrIsAligned(vm->limit, vm->align));
return TRUE;
}
/* VMCreate -- reserve some virtual address space, and create a VM structure */
Res VMCreate(VM *vmReturn, Size size)
{
LPVOID vbase;
SYSTEM_INFO si;
Align align;
VM vm;
Res res;
BOOL b;
AVER(vmReturn != NULL);
AVER(CHECKTYPE(LPVOID, Addr)); /* .assume.lpvoid-addr */
AVER(CHECKTYPE(SIZE_T, Size));
GetSystemInfo(&si);
align = (Align)si.dwPageSize;
AVER((DWORD)align == si.dwPageSize); /* check it didn't truncate */
AVER(SizeIsP2(align)); /* see .assume.sysalign */
size = SizeAlignUp(size, align);
if ((size == 0) || (size > (Size)(SIZE_T)-1))
return ResRESOURCE;
/* Allocate the vm descriptor. This is likely to be wasteful. */
vbase = VirtualAlloc(NULL, SizeAlignUp(sizeof(VMStruct), align),
MEM_COMMIT, PAGE_READWRITE);
if (vbase == NULL)
return ResMEMORY;
vm = (VM)vbase;
/* Allocate the address space. */
vbase = VirtualAlloc(NULL, size, MEM_RESERVE, PAGE_NOACCESS);
if (vbase == NULL) {
res = ResRESOURCE;
goto failReserve;
}
AVER(AddrIsAligned(vbase, align));
vm->align = align;
vm->base = (Addr)vbase;
vm->limit = AddrAdd(vbase, size);
vm->reserved = size;
vm->mapped = 0;
AVER(vm->base < vm->limit); /* .assume.not-last */
vm->sig = VMSig;
AVERT(VM, vm);
EVENT3(VMCreate, vm, vm->base, vm->limit);
*vmReturn = vm;
return ResOK;
failReserve:
b = VirtualFree((LPVOID)vm, (SIZE_T)0, MEM_RELEASE);
AVER(b != 0);
return res;
}
/* VMDestroy -- destroy the VM structure */
void VMDestroy(VM vm)
{
BOOL b;
AVERT(VM, vm);
AVER(vm->mapped == 0);
/* This appears to be pretty pointless, since the vm descriptor page
* is about to vanish completely. However, the VirtualFree might
* fail and it would be nice to have a dead sig there. */
vm->sig = SigInvalid;
b = VirtualFree((LPVOID)vm->base, (SIZE_T)0, MEM_RELEASE);
AVER(b != 0);
b = VirtualFree((LPVOID)vm, (SIZE_T)0, MEM_RELEASE);
AVER(b != 0);
EVENT1(VMDestroy, vm);
}
/* VMBase -- return the base address of the memory reserved */
Addr VMBase(VM vm)
{
AVERT(VM, vm);
return vm->base;
}
/* VMLimit -- return the limit address of the memory reserved */
Addr VMLimit(VM vm)
{
AVERT(VM, vm);
return vm->limit;
}
/* VMReserved -- return the amount of address space reserved */
Size VMReserved(VM vm)
{
AVERT(VM, vm);
return vm->reserved;
}
/* VMMapped -- return the amount of memory actually mapped */
Size VMMapped(VM vm)
{
AVERT(VM, vm);
return vm->mapped;
}
/* VMMap -- map the given range of memory */
Res VMMap(VM vm, Addr base, Addr limit)
{
LPVOID b;
Align align;
AVERT(VM, vm);
align = vm->align;
AVER(AddrIsAligned(base, align));
AVER(AddrIsAligned(limit, align));
AVER(vm->base <= base);
AVER(base < limit);
AVER(limit <= vm->limit);
/* .improve.query-map: We could check that the pages we are about to
* map are unmapped using VirtualQuery. */
b = VirtualAlloc((LPVOID)base, (SIZE_T)AddrOffset(base, limit),
MEM_COMMIT, PAGE_EXECUTE_READWRITE);
if (b == NULL)
return ResMEMORY;
AVER((Addr)b == base); /* base should've been aligned */
vm->mapped += AddrOffset(base, limit);
EVENT3(VMMap, vm, base, limit);
return ResOK;
}
/* VMUnmap -- unmap the given range of memory */
void VMUnmap(VM vm, Addr base, Addr limit)
{
Align align;
BOOL b;
AVERT(VM, vm);
align = vm->align;
AVER(AddrIsAligned(base, align));
AVER(AddrIsAligned(limit, align));
AVER(vm->base <= base);
AVER(base < limit);
AVER(limit <= vm->limit);
/* .improve.query-unmap: Could check that the pages we are about */
/* to unmap are mapped, using VirtualQuery. */
b = VirtualFree((LPVOID)base, (SIZE_T)AddrOffset(base, limit), MEM_DECOMMIT);
AVER(b != 0); /* .assume.free.success */
vm->mapped -= AddrOffset(base, limit);
EVENT3(VMUnmap, vm, base, limit);
}
/* C. COPYRIGHT AND LICENSE
*
* Copyright (C) 2001-2002 Ravenbrook Limited <http://www.ravenbrook.com/>.
* All rights reserved. This is an open source license. Contact
* Ravenbrook for commercial licensing options.
*
* 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. Redistributions in any form must be accompanied by information on how
* to obtain complete source code for this software and any accompanying
* software that uses this software. The source code must either be
* included in the distribution or be available for no more than the cost
* of distribution plus a nominal fee, and must be freely redistributable
* under reasonable conditions. For an executable file, complete source
* code means the source code for all modules it contains. It does not
* include source code for modules or files that typically accompany the
* major components of the operating system on which the executable file
* runs.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
* PURPOSE, OR NON-INFRINGEMENT, ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT HOLDERS AND 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.
*/