PGMR0SharedPage.cpp revision 5f4259f329a2073f6644399b6922077adca01529
/* $Id$ */
/** @file
* PGM - Page Manager and Monitor, Page Sharing, Ring-0.
*/
/*
* Copyright (C) 2010-2012 Oracle Corporation
*
* This file is part of VirtualBox Open Source Edition (OSE), as
* available from http://www.virtualbox.org. This file is free software;
* you can redistribute it and/or modify it under the terms of the GNU
* General Public License (GPL) as published by the Free Software
* Foundation, in version 2 as it comes in the "COPYING" file of the
* VirtualBox OSE distribution. VirtualBox OSE is distributed in the
* hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
*/
/*******************************************************************************
* Header Files *
*******************************************************************************/
#define LOG_GROUP LOG_GROUP_PGM_SHARED
#include <VBox/vmm/pgm.h>
#include <VBox/vmm/gmm.h>
#include "PGMInternal.h"
#include <VBox/vmm/vm.h>
#include "PGMInline.h"
#include <VBox/log.h>
#include <VBox/err.h>
#include <iprt/assert.h>
#include <iprt/mem.h>
#ifdef VBOX_WITH_PAGE_SHARING
/**
* Check a registered module for shared page changes.
*
* The PGM lock shall be taken prior to calling this method.
*
* @returns The following VBox status codes.
*
* @param pVM The VM handle.
* @param pGVM Pointer to the GVM instance data.
* @param idCpu The ID of the calling virtual CPU.
* @param pModule Global module description
* @param paRegionsGCPtrs Array parallel to pModules->aRegions with the
* addresses of the regions in the calling
* process.
*/
VMMR0DECL(int) PGMR0SharedModuleCheck(PVM pVM, PGVM pGVM, VMCPUID idCpu, PGMMSHAREDMODULE pModule, PCRTGCPTR64 paRegionsGCPtrs)
{
PVMCPU pVCpu = &pVM->aCpus[idCpu];
int rc = VINF_SUCCESS;
bool fFlushTLBs = false;
bool fFlushRemTLBs = false;
GMMSHAREDPAGEDESC PageDesc;
Log(("PGMR0SharedModuleCheck: check %s %s base=%RGv size=%x\n", pModule->szName, pModule->szVersion, pModule->Core.Key, pModule->cbModule));
PGM_LOCK_ASSERT_OWNER(pVM); /* This cannot fail as we grab the lock in pgmR3SharedModuleRegRendezvous before calling into ring-0. */
/*
* Check every region of the shared module.
*/
for (uint32_t idxRegion = 0; idxRegion < pModule->cRegions; idxRegion++)
{
RTGCPTR GCPtrPage = paRegionsGCPtrs[idxRegion] & ~(RTGCPTR)PAGE_OFFSET_MASK;
uint32_t cbLeft = pModule->aRegions[idxRegion].cb; Assert(!(cbLeft & PAGE_OFFSET_MASK));
uint32_t idxPage = 0;
while (cbLeft)
{
/** @todo inefficient to fetch each guest page like this... */
RTGCPHYS GCPhys;
uint64_t fFlags;
rc = PGMGstGetPage(pVCpu, GCPtrPage, &fFlags, &GCPhys);
if ( rc == VINF_SUCCESS
&& !(fFlags & X86_PTE_RW)) /* important as we make assumptions about this below! */
{
PPGMPAGE pPage = pgmPhysGetPage(pVM, GCPhys);
Assert(!pPage || !PGM_PAGE_IS_BALLOONED(pPage));
if ( pPage
&& PGM_PAGE_GET_STATE(pPage) == PGM_PAGE_STATE_ALLOCATED
&& PGM_PAGE_GET_READ_LOCKS(pPage) == 0
&& PGM_PAGE_GET_WRITE_LOCKS(pPage) == 0 )
{
PageDesc.idPage = PGM_PAGE_GET_PAGEID(pPage);
PageDesc.HCPhys = PGM_PAGE_GET_HCPHYS(pPage);
PageDesc.GCPhys = GCPhys;
rc = GMMR0SharedModuleCheckPage(pGVM, pModule, idxRegion, idxPage, &PageDesc);
if (RT_FAILURE(rc))
break;
/*
* Any change for this page?
*/
if (PageDesc.idPage != NIL_GMM_PAGEID)
{
Assert(PGM_PAGE_GET_STATE(pPage) == PGM_PAGE_STATE_ALLOCATED);
Log(("PGMR0SharedModuleCheck: shared page gst virt=%RGv phys=%RGp host %RHp->%RHp\n",
GCPtrPage, PageDesc.GCPhys, PGM_PAGE_GET_HCPHYS(pPage), PageDesc.HCPhys));
if (PageDesc.HCPhys != PGM_PAGE_GET_HCPHYS(pPage))
{
/* Page was replaced by an existing shared version
of it; clear all references first. */
bool fFlush = false;
rc = pgmPoolTrackUpdateGCPhys(pVM, PageDesc.GCPhys, pPage, true /* clear the entries */, &fFlush);
Assert( rc == VINF_SUCCESS
|| ( VMCPU_FF_ISSET(pVCpu, VMCPU_FF_PGM_SYNC_CR3)
&& (pVCpu->pgm.s.fSyncFlags & PGM_SYNC_CLEAR_PGM_POOL)));
if (rc == VINF_SUCCESS)
fFlushTLBs |= fFlush;
fFlushRemTLBs = true;
/* Update the physical address and page id now. */
PGM_PAGE_SET_HCPHYS(pVM, pPage, PageDesc.HCPhys);
PGM_PAGE_SET_PAGEID(pVM, pPage, PageDesc.idPage);
/* Invalidate page map TLB entry for this page too. */
pgmPhysInvalidatePageMapTLBEntry(pVM, PageDesc.GCPhys);
pVM->pgm.s.cReusedSharedPages++;
}
/* else: nothing changed (== this page is now a shared
page), so no need to flush anything. */
pVM->pgm.s.cSharedPages++;
pVM->pgm.s.cPrivatePages--;
PGM_PAGE_SET_STATE(pVM, pPage, PGM_PAGE_STATE_SHARED);
}
}
}
else
{
Assert( rc == VINF_SUCCESS
|| rc == VERR_PAGE_NOT_PRESENT
|| rc == VERR_PAGE_MAP_LEVEL4_NOT_PRESENT
|| rc == VERR_PAGE_DIRECTORY_PTR_NOT_PRESENT
|| rc == VERR_PAGE_TABLE_NOT_PRESENT);
rc = VINF_SUCCESS; /* ignore error */
}
idxPage++;
GCPtrPage += PAGE_SIZE;
cbLeft -= PAGE_SIZE;
}
}
/*
* Do TLB flushing if necessary.
*/
if (fFlushTLBs)
PGM_INVL_ALL_VCPU_TLBS(pVM);
if (fFlushRemTLBs)
for (VMCPUID idCurCpu = 0; idCurCpu < pVM->cCpus; idCurCpu++)
CPUMSetChangedFlags(&pVM->aCpus[idCurCpu], CPUM_CHANGED_GLOBAL_TLB_FLUSH);
return rc;
}
#endif /* VBOX_WITH_PAGE_SHARING */