source: vbox/trunk/src/VBox/VMM/include/PGMInline.h@ 96622

/* $Id: PGMInline.h 96407 2022-08-22 17:43:14Z vboxsync $ */
/** @file
 * PGM - Inlined functions.
 */

/*
 * Copyright (C) 2006-2022 Oracle and/or its affiliates.
 *
 * This file is part of VirtualBox base platform packages, as
 * available from https://www.virtualbox.org.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation, in version 3 of the
 * License.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <https://www.gnu.org/licenses>.
 *
 * SPDX-License-Identifier: GPL-3.0-only
 */

#ifndef VMM_INCLUDED_SRC_include_PGMInline_h
#define VMM_INCLUDED_SRC_include_PGMInline_h
#ifndef RT_WITHOUT_PRAGMA_ONCE
# pragma once
#endif

#include <VBox/cdefs.h>
#include <VBox/types.h>
#include <VBox/err.h>
#include <VBox/vmm/stam.h>
#include <VBox/param.h>
#include <VBox/vmm/vmm.h>
#include <VBox/vmm/mm.h>
#include <VBox/vmm/pdmcritsect.h>
#include <VBox/vmm/pdmapi.h>
#include <VBox/dis.h>
#include <VBox/vmm/dbgf.h>
#include <VBox/log.h>
#include <VBox/vmm/gmm.h>
#include <VBox/vmm/hm.h>
#include <VBox/vmm/nem.h>
#include <iprt/asm.h>
#include <iprt/assert.h>
#include <iprt/avl.h>
#include <iprt/critsect.h>
#include <iprt/sha.h>



/** @addtogroup grp_pgm_int   Internals
 * @internal
 * @{
 */

/**
 * Gets the PGMRAMRANGE structure for a guest page.
 *
 * @returns Pointer to the RAM range on success.
 * @returns NULL on a VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS condition.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 */
DECLINLINE(PPGMRAMRANGE) pgmPhysGetRange(PVMCC pVM, RTGCPHYS GCPhys)
{
    PPGMRAMRANGE pRam = pVM->pgm.s.CTX_SUFF(apRamRangesTlb)[PGM_RAMRANGE_TLB_IDX(GCPhys)];
    if (!pRam || GCPhys - pRam->GCPhys >= pRam->cb)
        return pgmPhysGetRangeSlow(pVM, GCPhys);
    STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,RamRangeTlbHits));
    return pRam;
}


/**
 * Gets the PGMRAMRANGE structure for a guest page, if unassigned get the ram
 * range above it.
 *
 * @returns Pointer to the RAM range on success.
 * @returns NULL if the address is located after the last range.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 */
DECLINLINE(PPGMRAMRANGE) pgmPhysGetRangeAtOrAbove(PVMCC pVM, RTGCPHYS GCPhys)
{
    PPGMRAMRANGE pRam = pVM->pgm.s.CTX_SUFF(apRamRangesTlb)[PGM_RAMRANGE_TLB_IDX(GCPhys)];
    if (   !pRam
        || (GCPhys - pRam->GCPhys) >= pRam->cb)
        return pgmPhysGetRangeAtOrAboveSlow(pVM, GCPhys);
    STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,RamRangeTlbHits));
    return pRam;
}


/**
 * Gets the PGMPAGE structure for a guest page.
 *
 * @returns Pointer to the page on success.
 * @returns NULL on a VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS condition.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 */
DECLINLINE(PPGMPAGE) pgmPhysGetPage(PVMCC pVM, RTGCPHYS GCPhys)
{
    PPGMRAMRANGE pRam = pVM->pgm.s.CTX_SUFF(apRamRangesTlb)[PGM_RAMRANGE_TLB_IDX(GCPhys)];
    RTGCPHYS off;
    if (   pRam
        && (off = GCPhys - pRam->GCPhys) < pRam->cb)
    {
        STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,RamRangeTlbHits));
        return &pRam->aPages[off >> GUEST_PAGE_SHIFT];
    }
    return pgmPhysGetPageSlow(pVM, GCPhys);
}


/**
 * Gets the PGMPAGE structure for a guest page.
 *
 * Old Phys code: Will make sure the page is present.
 *
 * @returns VBox status code.
 * @retval  VINF_SUCCESS and a valid *ppPage on success.
 * @retval  VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS if the address isn't valid.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 * @param   ppPage      Where to store the page pointer on success.
 */
DECLINLINE(int) pgmPhysGetPageEx(PVMCC pVM, RTGCPHYS GCPhys, PPPGMPAGE ppPage)
{
    PPGMRAMRANGE pRam = pVM->pgm.s.CTX_SUFF(apRamRangesTlb)[PGM_RAMRANGE_TLB_IDX(GCPhys)];
    RTGCPHYS off;
    if (   !pRam
        || (off = GCPhys - pRam->GCPhys) >= pRam->cb)
        return pgmPhysGetPageExSlow(pVM, GCPhys, ppPage);
    *ppPage = &pRam->aPages[off >> GUEST_PAGE_SHIFT];
    STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,RamRangeTlbHits));
    return VINF_SUCCESS;
}


/**
 * Gets the PGMPAGE structure for a guest page.
 *
 * Old Phys code: Will make sure the page is present.
 *
 * @returns VBox status code.
 * @retval  VINF_SUCCESS and a valid *ppPage on success.
 * @retval  VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS if the address isn't valid.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 * @param   ppPage      Where to store the page pointer on success.
 * @param   ppRamHint   Where to read and store the ram list hint.
 *                      The caller initializes this to NULL before the call.
 */
DECLINLINE(int) pgmPhysGetPageWithHintEx(PVMCC pVM, RTGCPHYS GCPhys, PPPGMPAGE ppPage, PPGMRAMRANGE *ppRamHint)
{
    RTGCPHYS off;
    PPGMRAMRANGE pRam = *ppRamHint;
    if (    !pRam
        ||  RT_UNLIKELY((off = GCPhys - pRam->GCPhys) >= pRam->cb))
    {
        pRam = pVM->pgm.s.CTX_SUFF(apRamRangesTlb)[PGM_RAMRANGE_TLB_IDX(GCPhys)];
        if (   !pRam
            || (off = GCPhys - pRam->GCPhys) >= pRam->cb)
            return pgmPhysGetPageAndRangeExSlow(pVM, GCPhys, ppPage, ppRamHint);

        STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,RamRangeTlbHits));
        *ppRamHint = pRam;
    }
    *ppPage = &pRam->aPages[off >> GUEST_PAGE_SHIFT];
    return VINF_SUCCESS;
}


/**
 * Gets the PGMPAGE structure for a guest page together with the PGMRAMRANGE.
 *
 * @returns Pointer to the page on success.
 * @returns NULL on a VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS condition.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 * @param   ppPage      Where to store the pointer to the PGMPAGE structure.
 * @param   ppRam       Where to store the pointer to the PGMRAMRANGE structure.
 */
DECLINLINE(int) pgmPhysGetPageAndRangeEx(PVMCC pVM, RTGCPHYS GCPhys, PPPGMPAGE ppPage, PPGMRAMRANGE *ppRam)
{
    PPGMRAMRANGE pRam = pVM->pgm.s.CTX_SUFF(apRamRangesTlb)[PGM_RAMRANGE_TLB_IDX(GCPhys)];
    RTGCPHYS off;
    if (   !pRam
        || (off = GCPhys - pRam->GCPhys) >= pRam->cb)
        return pgmPhysGetPageAndRangeExSlow(pVM, GCPhys, ppPage, ppRam);

    STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,RamRangeTlbHits));
    *ppRam = pRam;
    *ppPage = &pRam->aPages[off >> GUEST_PAGE_SHIFT];
    return VINF_SUCCESS;
}


/**
 * Convert GC Phys to HC Phys.
 *
 * @returns VBox status code.
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The GC physical address.
 * @param   pHCPhys     Where to store the corresponding HC physical address.
 *
 * @deprecated  Doesn't deal with zero, shared or write monitored pages.
 *              Avoid when writing new code!
 */
DECLINLINE(int) pgmRamGCPhys2HCPhys(PVMCC pVM, RTGCPHYS GCPhys, PRTHCPHYS pHCPhys)
{
    PPGMPAGE pPage;
    int rc = pgmPhysGetPageEx(pVM, GCPhys, &pPage);
    if (RT_FAILURE(rc))
        return rc;
    *pHCPhys = PGM_PAGE_GET_HCPHYS(pPage) | (GCPhys & GUEST_PAGE_OFFSET_MASK);
    return VINF_SUCCESS;
}


/**
 * Queries the Physical TLB entry for a physical guest page,
 * attempting to load the TLB entry if necessary.
 *
 * @returns VBox status code.
 * @retval  VINF_SUCCESS on success
 * @retval  VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS if it's not a valid physical address.
 *
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The address of the guest page.
 * @param   ppTlbe      Where to store the pointer to the TLB entry.
 */
DECLINLINE(int) pgmPhysPageQueryTlbe(PVMCC pVM, RTGCPHYS GCPhys, PPPGMPAGEMAPTLBE ppTlbe)
{
    int rc;
    PPGMPAGEMAPTLBE pTlbe = &pVM->pgm.s.CTX_SUFF(PhysTlb).aEntries[PGM_PAGEMAPTLB_IDX(GCPhys)];
    if (pTlbe->GCPhys == (GCPhys & X86_PTE_PAE_PG_MASK))
    {
        STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,PageMapTlbHits));
        rc = VINF_SUCCESS;
    }
    else
        rc = pgmPhysPageLoadIntoTlb(pVM, GCPhys);
    *ppTlbe = pTlbe;
    return rc;
}


/**
 * Queries the Physical TLB entry for a physical guest page,
 * attempting to load the TLB entry if necessary.
 *
 * @returns VBox status code.
 * @retval  VINF_SUCCESS on success
 * @retval  VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS if it's not a valid physical address.
 *
 * @param   pVM         The cross context VM structure.
 * @param   pPage       Pointer to the PGMPAGE structure corresponding to
 *                      GCPhys.
 * @param   GCPhys      The address of the guest page.
 * @param   ppTlbe      Where to store the pointer to the TLB entry.
 */
DECLINLINE(int) pgmPhysPageQueryTlbeWithPage(PVMCC pVM, PPGMPAGE pPage, RTGCPHYS GCPhys, PPPGMPAGEMAPTLBE ppTlbe)
{
    int rc;
    PPGMPAGEMAPTLBE pTlbe = &pVM->pgm.s.CTX_SUFF(PhysTlb).aEntries[PGM_PAGEMAPTLB_IDX(GCPhys)];
    if (pTlbe->GCPhys == (GCPhys & X86_PTE_PAE_PG_MASK))
    {
        STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,PageMapTlbHits));
        rc = VINF_SUCCESS;
        AssertPtr(pTlbe->pv);
#ifdef IN_RING3
        Assert(!pTlbe->pMap || RT_VALID_PTR(pTlbe->pMap->pv));
#endif
    }
    else
        rc = pgmPhysPageLoadIntoTlbWithPage(pVM, pPage, GCPhys);
    *ppTlbe = pTlbe;
    return rc;
}


/**
 * Calculates NEM page protection flags.
 */
DECL_FORCE_INLINE(uint32_t) pgmPhysPageCalcNemProtection(PPGMPAGE pPage, PGMPAGETYPE enmType)
{
    /*
     * Deal with potentially writable pages first.
     */
    if (PGMPAGETYPE_IS_RWX(enmType))
    {
        if (!PGM_PAGE_HAS_ACTIVE_HANDLERS(pPage))
        {
            if (PGM_PAGE_IS_ALLOCATED(pPage))
                return NEM_PAGE_PROT_READ | NEM_PAGE_PROT_EXECUTE | NEM_PAGE_PROT_WRITE;
            return NEM_PAGE_PROT_READ | NEM_PAGE_PROT_EXECUTE;
        }
        if (!PGM_PAGE_HAS_ACTIVE_ALL_HANDLERS(pPage))
            return NEM_PAGE_PROT_READ | NEM_PAGE_PROT_EXECUTE;
    }
    /*
     * Potentially readable & executable pages.
     */
    else if (   PGMPAGETYPE_IS_ROX(enmType)
             && !PGM_PAGE_HAS_ACTIVE_ALL_HANDLERS(pPage))
        return NEM_PAGE_PROT_READ | NEM_PAGE_PROT_EXECUTE;

    /*
     * The rest is needs special access handling.
     */
    return NEM_PAGE_PROT_NONE;
}


/**
 * Enables write monitoring for an allocated page.
 *
 * The caller is responsible for updating the shadow page tables.
 *
 * @param   pVM         The cross context VM structure.
 * @param   pPage       The page to write monitor.
 * @param   GCPhysPage  The address of the page.
 */
DECLINLINE(void) pgmPhysPageWriteMonitor(PVMCC pVM, PPGMPAGE pPage, RTGCPHYS GCPhysPage)
{
    Assert(PGM_PAGE_GET_STATE(pPage) == PGM_PAGE_STATE_ALLOCATED);
    PGM_LOCK_ASSERT_OWNER(pVM);

    PGM_PAGE_SET_STATE(pVM, pPage, PGM_PAGE_STATE_WRITE_MONITORED);
    pVM->pgm.s.cMonitoredPages++;

    /* Large pages must disabled. */
    if (PGM_PAGE_GET_PDE_TYPE(pPage) == PGM_PAGE_PDE_TYPE_PDE)
    {
        PPGMPAGE pFirstPage = pgmPhysGetPage(pVM, GCPhysPage & X86_PDE2M_PAE_PG_MASK);
        AssertFatal(pFirstPage);
        if (PGM_PAGE_GET_PDE_TYPE(pFirstPage) == PGM_PAGE_PDE_TYPE_PDE)
        {
            PGM_PAGE_SET_PDE_TYPE(pVM, pFirstPage, PGM_PAGE_PDE_TYPE_PDE_DISABLED);
            pVM->pgm.s.cLargePagesDisabled++;
        }
        else
            Assert(PGM_PAGE_GET_PDE_TYPE(pFirstPage) == PGM_PAGE_PDE_TYPE_PDE_DISABLED);
    }

#ifdef VBOX_WITH_NATIVE_NEM
    /* Tell NEM. */
    if (VM_IS_NEM_ENABLED(pVM))
    {
        uint8_t      u2State = PGM_PAGE_GET_NEM_STATE(pPage);
        PGMPAGETYPE  enmType = (PGMPAGETYPE)PGM_PAGE_GET_TYPE(pPage);
        PPGMRAMRANGE pRam    = pgmPhysGetRange(pVM, GCPhysPage);
        NEMHCNotifyPhysPageProtChanged(pVM, GCPhysPage, PGM_PAGE_GET_HCPHYS(pPage),
                                       pRam ? PGM_RAMRANGE_CALC_PAGE_R3PTR(pRam, GCPhysPage) : NULL,
                                       pgmPhysPageCalcNemProtection(pPage, enmType), enmType, &u2State);
        PGM_PAGE_SET_NEM_STATE(pPage, u2State);
    }
#endif
}


/**
 * Checks if the no-execute (NX) feature is active (EFER.NXE=1).
 *
 * Only used when the guest is in PAE or long mode.  This is inlined so that we
 * can perform consistency checks in debug builds.
 *
 * @returns true if it is, false if it isn't.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECL_FORCE_INLINE(bool) pgmGstIsNoExecuteActive(PVMCPUCC pVCpu)
{
    Assert(pVCpu->pgm.s.fNoExecuteEnabled == CPUMIsGuestNXEnabled(pVCpu));
    Assert(CPUMIsGuestInPAEMode(pVCpu) || CPUMIsGuestInLongMode(pVCpu));
    return pVCpu->pgm.s.fNoExecuteEnabled;
}


/**
 * Checks if the page size extension (PSE) is currently enabled (CR4.PSE=1).
 *
 * Only used when the guest is in paged 32-bit mode.  This is inlined so that
 * we can perform consistency checks in debug builds.
 *
 * @returns true if it is, false if it isn't.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECL_FORCE_INLINE(bool) pgmGst32BitIsPageSizeExtActive(PVMCPUCC pVCpu)
{
    Assert(pVCpu->pgm.s.fGst32BitPageSizeExtension == CPUMIsGuestPageSizeExtEnabled(pVCpu));
    Assert(!CPUMIsGuestInPAEMode(pVCpu));
    Assert(!CPUMIsGuestInLongMode(pVCpu));
    return pVCpu->pgm.s.fGst32BitPageSizeExtension;
}


/**
 * Calculated the guest physical address of the large (4 MB) page in 32 bits paging mode.
 * Takes PSE-36 into account.
 *
 * @returns guest physical address
 * @param   pVM         The cross context VM structure.
 * @param   Pde         Guest Pde
 */
DECLINLINE(RTGCPHYS) pgmGstGet4MBPhysPage(PVMCC pVM, X86PDE Pde)
{
    RTGCPHYS GCPhys = Pde.u & X86_PDE4M_PG_MASK;
    GCPhys |= (RTGCPHYS)(Pde.u & X86_PDE4M_PG_HIGH_MASK) << X86_PDE4M_PG_HIGH_SHIFT;

    return GCPhys & pVM->pgm.s.GCPhys4MBPSEMask;
}


/**
 * Gets the address the guest page directory (32-bit paging).
 *
 * @returns VBox status code.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   ppPd        Where to return the mapping. This is always set.
 */
DECLINLINE(int) pgmGstGet32bitPDPtrEx(PVMCPUCC pVCpu, PX86PD *ppPd)
{
    *ppPd = pVCpu->pgm.s.CTX_SUFF(pGst32BitPd);
    if (RT_UNLIKELY(!*ppPd))
        return pgmGstLazyMap32BitPD(pVCpu, ppPd);
    return VINF_SUCCESS;
}


/**
 * Gets the address the guest page directory (32-bit paging).
 *
 * @returns Pointer to the page directory entry in question.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PX86PD) pgmGstGet32bitPDPtr(PVMCPUCC pVCpu)
{
    PX86PD pGuestPD = pVCpu->pgm.s.CTX_SUFF(pGst32BitPd);
    if (RT_UNLIKELY(!pGuestPD))
    {
        int rc = pgmGstLazyMap32BitPD(pVCpu, &pGuestPD);
        if (RT_FAILURE(rc))
            return NULL;
    }
    return pGuestPD;
}


/**
 * Gets the guest page directory pointer table.
 *
 * @returns VBox status code.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   ppPdpt      Where to return the mapping.  This is always set.
 */
DECLINLINE(int) pgmGstGetPaePDPTPtrEx(PVMCPUCC pVCpu, PX86PDPT *ppPdpt)
{
    *ppPdpt = pVCpu->pgm.s.CTX_SUFF(pGstPaePdpt);
    if (RT_UNLIKELY(!*ppPdpt))
        return pgmGstLazyMapPaePDPT(pVCpu, ppPdpt);
    return VINF_SUCCESS;
}


/**
 * Gets the guest page directory pointer table.
 *
 * @returns Pointer to the page directory in question.
 * @returns NULL if the page directory is not present or on an invalid page.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PX86PDPT) pgmGstGetPaePDPTPtr(PVMCPUCC pVCpu)
{
    PX86PDPT pGuestPdpt;
    int rc = pgmGstGetPaePDPTPtrEx(pVCpu, &pGuestPdpt);
    AssertMsg(RT_SUCCESS(rc) || rc == VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS, ("%Rrc\n", rc)); NOREF(rc);
    return pGuestPdpt;
}


/**
 * Gets the guest page directory pointer table entry for the specified address.
 *
 * @returns Pointer to the page directory in question.
 * @returns NULL if the page directory is not present or on an invalid page.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(PX86PDPE) pgmGstGetPaePDPEPtr(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    AssertGCPtr32(GCPtr);

    PX86PDPT pGuestPDPT = pVCpu->pgm.s.CTX_SUFF(pGstPaePdpt);
    if (RT_UNLIKELY(!pGuestPDPT))
    {
        int rc = pgmGstLazyMapPaePDPT(pVCpu, &pGuestPDPT);
        if (RT_FAILURE(rc))
            return NULL;
    }
    return &pGuestPDPT->a[(uint32_t)GCPtr >> X86_PDPT_SHIFT];
}


/**
 * Gets the page directory entry for the specified address.
 *
 * @returns The page directory entry in question.
 * @returns A non-present entry if the page directory is not present or on an invalid page.
 * @param   pVCpu       The cross context virtual CPU structure of the calling EMT.
 * @param   GCPtr       The address.
 */
DECLINLINE(X86PDEPAE) pgmGstGetPaePDE(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    AssertGCPtr32(GCPtr);
    PX86PDPT    pGuestPDPT = pgmGstGetPaePDPTPtr(pVCpu);
    if (RT_LIKELY(pGuestPDPT))
    {
        const unsigned iPdpt = (uint32_t)GCPtr >> X86_PDPT_SHIFT;
        if ((pGuestPDPT->a[iPdpt].u & (pVCpu->pgm.s.fGstPaeMbzPdpeMask | X86_PDPE_P)) == X86_PDPE_P)
        {
            const unsigned iPD = (GCPtr >> X86_PD_PAE_SHIFT) & X86_PD_PAE_MASK;
            PX86PDPAE   pGuestPD = pVCpu->pgm.s.CTX_SUFF(apGstPaePDs)[iPdpt];
            if (    !pGuestPD
                ||  (pGuestPDPT->a[iPdpt].u & X86_PDPE_PG_MASK) != pVCpu->pgm.s.aGCPhysGstPaePDs[iPdpt])
                pgmGstLazyMapPaePD(pVCpu, iPdpt, &pGuestPD);
            if (pGuestPD)
                return pGuestPD->a[iPD];
        }
    }

    X86PDEPAE ZeroPde = {0};
    return ZeroPde;
}


/**
 * Gets the page directory pointer table entry for the specified address
 * and returns the index into the page directory
 *
 * @returns Pointer to the page directory in question.
 * @returns NULL if the page directory is not present or on an invalid page.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 * @param   piPD        Receives the index into the returned page directory
 * @param   pPdpe       Receives the page directory pointer entry. Optional.
 */
DECLINLINE(PX86PDPAE) pgmGstGetPaePDPtr(PVMCPUCC pVCpu, RTGCPTR GCPtr, unsigned *piPD, PX86PDPE pPdpe)
{
    AssertGCPtr32(GCPtr);

    /* The PDPE. */
    PX86PDPT pGuestPDPT = pgmGstGetPaePDPTPtr(pVCpu);
    if (pGuestPDPT)
    {
        const unsigned     iPdpt = (uint32_t)GCPtr >> X86_PDPT_SHIFT;
        X86PGPAEUINT const uPdpe = pGuestPDPT->a[iPdpt].u;
        if (pPdpe)
            pPdpe->u = uPdpe;
        if ((uPdpe & (pVCpu->pgm.s.fGstPaeMbzPdpeMask | X86_PDPE_P)) == X86_PDPE_P)
        {

            /* The PDE. */
            PX86PDPAE   pGuestPD = pVCpu->pgm.s.CTX_SUFF(apGstPaePDs)[iPdpt];
            if (    !pGuestPD
                ||  (uPdpe & X86_PDPE_PG_MASK) != pVCpu->pgm.s.aGCPhysGstPaePDs[iPdpt])
                pgmGstLazyMapPaePD(pVCpu, iPdpt, &pGuestPD);
            *piPD = (GCPtr >> X86_PD_PAE_SHIFT) & X86_PD_PAE_MASK;
            return pGuestPD;
        }
    }
    return NULL;
}


/**
 * Gets the page map level-4 pointer for the guest.
 *
 * @returns VBox status code.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   ppPml4      Where to return the mapping.  Always set.
 */
DECLINLINE(int) pgmGstGetLongModePML4PtrEx(PVMCPUCC pVCpu, PX86PML4 *ppPml4)
{
    *ppPml4 = pVCpu->pgm.s.CTX_SUFF(pGstAmd64Pml4);
    if (RT_UNLIKELY(!*ppPml4))
        return pgmGstLazyMapPml4(pVCpu, ppPml4);
    return VINF_SUCCESS;
}


/**
 * Gets the page map level-4 pointer for the guest.
 *
 * @returns Pointer to the PML4 page.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PX86PML4) pgmGstGetLongModePML4Ptr(PVMCPUCC pVCpu)
{
    PX86PML4 pGuestPml4;
    int rc = pgmGstGetLongModePML4PtrEx(pVCpu, &pGuestPml4);
    AssertMsg(RT_SUCCESS(rc) || rc == VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS, ("%Rrc\n", rc)); NOREF(rc);
    return pGuestPml4;
}


/**
 * Gets the pointer to a page map level-4 entry.
 *
 * @returns Pointer to the PML4 entry.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   iPml4       The index.
 * @remarks Only used by AssertCR3.
 */
DECLINLINE(PX86PML4E) pgmGstGetLongModePML4EPtr(PVMCPUCC pVCpu, unsigned int iPml4)
{
    PX86PML4 pGuestPml4 = pVCpu->pgm.s.CTX_SUFF(pGstAmd64Pml4);
    if (pGuestPml4)
    { /* likely */ }
    else
    {
         int rc = pgmGstLazyMapPml4(pVCpu, &pGuestPml4);
         AssertRCReturn(rc, NULL);
    }
    return &pGuestPml4->a[iPml4];
}


/**
 * Gets the page directory entry for the specified address.
 *
 * @returns The page directory entry in question.
 * @returns A non-present entry if the page directory is not present or on an invalid page.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(X86PDEPAE) pgmGstGetLongModePDE(PVMCPUCC pVCpu, RTGCPTR64 GCPtr)
{
    /*
     * Note! To keep things simple, ASSUME invalid physical addresses will
     *       cause X86_TRAP_PF_RSVD.  This isn't a problem until we start
     *       supporting 52-bit wide physical guest addresses.
     */
    PCX86PML4 pGuestPml4 = pgmGstGetLongModePML4Ptr(pVCpu);
    if (RT_LIKELY(pGuestPml4))
    {
        const unsigned     iPml4  = (GCPtr >> X86_PML4_SHIFT) & X86_PML4_MASK;
        X86PGPAEUINT const uPml4e = pGuestPml4->a[iPml4].u;
        if ((uPml4e & (pVCpu->pgm.s.fGstAmd64MbzPml4eMask | X86_PML4E_P)) == X86_PML4E_P)
        {
            PCX86PDPT pPdptTemp;
            int rc = PGM_GCPHYS_2_PTR_BY_VMCPU(pVCpu, uPml4e & X86_PML4E_PG_MASK, &pPdptTemp);
            if (RT_SUCCESS(rc))
            {
                const unsigned     iPdpt  = (GCPtr >> X86_PDPT_SHIFT) & X86_PDPT_MASK_AMD64;
                X86PGPAEUINT const uPdpte = pPdptTemp->a[iPdpt].u;
                if ((uPdpte & (pVCpu->pgm.s.fGstAmd64MbzPdpeMask | X86_PDPE_P)) == X86_PDPE_P)
                {
                    PCX86PDPAE pPD;
                    rc = PGM_GCPHYS_2_PTR_BY_VMCPU(pVCpu, uPdpte & X86_PDPE_PG_MASK, &pPD);
                    if (RT_SUCCESS(rc))
                    {
                        const unsigned iPD = (GCPtr >> X86_PD_PAE_SHIFT) & X86_PD_PAE_MASK;
                        return pPD->a[iPD];
                    }
                }
            }
            AssertMsg(RT_SUCCESS(rc) || rc == VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS, ("%Rrc\n", rc));
        }
    }

    X86PDEPAE ZeroPde = {0};
    return ZeroPde;
}


/**
 * Gets the GUEST page directory pointer for the specified address.
 *
 * @returns The page directory in question.
 * @returns NULL if the page directory is not present or on an invalid page.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 * @param   ppPml4e     Page Map Level-4 Entry (out)
 * @param   pPdpe       Page directory pointer table entry (out)
 * @param   piPD        Receives the index into the returned page directory
 */
DECLINLINE(PX86PDPAE) pgmGstGetLongModePDPtr(PVMCPUCC pVCpu, RTGCPTR64 GCPtr, PX86PML4E *ppPml4e, PX86PDPE pPdpe, unsigned *piPD)
{
    /* The PMLE4. */
    PX86PML4 pGuestPml4 = pgmGstGetLongModePML4Ptr(pVCpu);
    if (pGuestPml4)
    {
        const unsigned     iPml4  = (GCPtr >> X86_PML4_SHIFT) & X86_PML4_MASK;
        *ppPml4e = &pGuestPml4->a[iPml4];
        X86PGPAEUINT const uPml4e = pGuestPml4->a[iPml4].u;
        if ((uPml4e & (pVCpu->pgm.s.fGstAmd64MbzPml4eMask | X86_PML4E_P)) == X86_PML4E_P)
        {
            /* The PDPE. */
            PCX86PDPT pPdptTemp;
            int rc = PGM_GCPHYS_2_PTR_BY_VMCPU(pVCpu, uPml4e & X86_PML4E_PG_MASK, &pPdptTemp);
            if (RT_SUCCESS(rc))
            {
                const unsigned     iPdpt = (GCPtr >> X86_PDPT_SHIFT) & X86_PDPT_MASK_AMD64;
                X86PGPAEUINT const uPdpe = pPdptTemp->a[iPdpt].u;
                pPdpe->u = uPdpe;
                if ((uPdpe & (pVCpu->pgm.s.fGstAmd64MbzPdpeMask | X86_PDPE_P)) == X86_PDPE_P)
                {
                    /* The PDE. */
                    PX86PDPAE pPD;
                    rc = PGM_GCPHYS_2_PTR_BY_VMCPU(pVCpu, uPdpe & X86_PDPE_PG_MASK, &pPD);
                    if (RT_SUCCESS(rc))
                    {
                        *piPD = (GCPtr >> X86_PD_PAE_SHIFT) & X86_PD_PAE_MASK;
                        return pPD;
                    }
                    AssertMsg(rc == VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS, ("%Rrc\n", rc));
                }
            }
            else
                AssertMsg(rc == VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS, ("%Rrc\n", rc));
        }
    }
    return NULL;
}


#ifdef VBOX_WITH_NESTED_HWVIRT_VMX_EPT
/**
 * Gets the pointer to a page map level-4 entry when the guest using EPT paging.
 *
 * @returns Pointer to the PML4 entry.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   iPml4       The index.
 * @remarks Only used by AssertCR3.
 */
DECLINLINE(PEPTPML4E) pgmGstGetEptPML4EPtr(PVMCPUCC pVCpu, unsigned int iPml4)
{
    PEPTPML4 pEptPml4 = pVCpu->pgm.s.CTX_SUFF(pGstEptPml4);
    if (pEptPml4)
    { /* likely */ }
    else
    {
         int const rc = pgmGstLazyMapEptPml4(pVCpu, &pEptPml4);
         AssertRCReturn(rc, NULL);
    }
    return &pEptPml4->a[iPml4];
}


/**
 * Gets the page map level-4 pointer for the guest when the guest is using EPT
 * paging.
 *
 * @returns VBox status code.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   ppEptPml4   Where to return the mapping.  Always set.
 */
DECLINLINE(int) pgmGstGetEptPML4PtrEx(PVMCPUCC pVCpu, PEPTPML4 *ppEptPml4)
{
    *ppEptPml4 = pVCpu->pgm.s.CTX_SUFF(pGstEptPml4);
    if (RT_UNLIKELY(!*ppEptPml4))
        return pgmGstLazyMapEptPml4(pVCpu, ppEptPml4);
    return VINF_SUCCESS;
}


/**
 * Gets the page map level-4 pointer for the guest when the guest is using EPT
 * paging.
 *
 * @returns Pointer to the EPT PML4 page.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PEPTPML4) pgmGstGetEptPML4Ptr(PVMCPUCC pVCpu)
{
    PEPTPML4 pEptPml4;
    int rc = pgmGstGetEptPML4PtrEx(pVCpu, &pEptPml4);
    AssertMsg(RT_SUCCESS(rc) || rc == VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS, ("%Rrc\n", rc)); NOREF(rc);
    return pEptPml4;
}
#endif /* VBOX_WITH_NESTED_HWVIRT_VMX_EPT */


/**
 * Gets the shadow page directory, 32-bit.
 *
 * @returns Pointer to the shadow 32-bit PD.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PX86PD) pgmShwGet32BitPDPtr(PVMCPUCC pVCpu)
{
    return (PX86PD)PGMPOOL_PAGE_2_PTR_V2(pVCpu->CTX_SUFF(pVM), pVCpu, pVCpu->pgm.s.CTX_SUFF(pShwPageCR3));
}


/**
 * Gets the shadow page directory entry for the specified address, 32-bit.
 *
 * @returns Shadow 32-bit PDE.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(X86PDE) pgmShwGet32BitPDE(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    PX86PD pShwPde = pgmShwGet32BitPDPtr(pVCpu);
    if (!pShwPde)
    {
        X86PDE ZeroPde = {0};
        return ZeroPde;
    }
    return pShwPde->a[(uint32_t)GCPtr >> X86_PD_SHIFT];
}


/**
 * Gets the pointer to the shadow page directory entry for the specified
 * address, 32-bit.
 *
 * @returns Pointer to the shadow 32-bit PDE.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(PX86PDE) pgmShwGet32BitPDEPtr(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    PX86PD pPde = pgmShwGet32BitPDPtr(pVCpu);
    AssertReturn(pPde, NULL);
    return &pPde->a[(uint32_t)GCPtr >> X86_PD_SHIFT];
}


/**
 * Gets the shadow page pointer table, PAE.
 *
 * @returns Pointer to the shadow PAE PDPT.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PX86PDPT) pgmShwGetPaePDPTPtr(PVMCPUCC pVCpu)
{
    return (PX86PDPT)PGMPOOL_PAGE_2_PTR_V2(pVCpu->CTX_SUFF(pVM), pVCpu, pVCpu->pgm.s.CTX_SUFF(pShwPageCR3));
}


/**
 * Gets the shadow page directory for the specified address, PAE.
 *
 * @returns Pointer to the shadow PD.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   pPdpt       Pointer to the page directory pointer table.
 * @param   GCPtr       The address.
 */
DECLINLINE(PX86PDPAE) pgmShwGetPaePDPtr(PVMCPUCC pVCpu, PX86PDPT pPdpt, RTGCPTR GCPtr)
{
    const unsigned  iPdpt = (uint32_t)GCPtr >> X86_PDPT_SHIFT;
    if (pPdpt->a[iPdpt].u & X86_PDPE_P)
    {
        /* Fetch the pgm pool shadow descriptor. */
        PVMCC           pVM     = pVCpu->CTX_SUFF(pVM);
        PPGMPOOLPAGE    pShwPde = pgmPoolGetPage(pVM->pgm.s.CTX_SUFF(pPool), pPdpt->a[iPdpt].u & X86_PDPE_PG_MASK);
        AssertReturn(pShwPde, NULL);

        return (PX86PDPAE)PGMPOOL_PAGE_2_PTR_V2(pVM, pVCpu, pShwPde);
    }
    return NULL;
}


/**
 * Gets the shadow page directory for the specified address, PAE.
 *
 * @returns Pointer to the shadow PD.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(PX86PDPAE) pgmShwGetPaePDPtr(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    return pgmShwGetPaePDPtr(pVCpu, pgmShwGetPaePDPTPtr(pVCpu), GCPtr);
}


/**
 * Gets the shadow page directory entry, PAE.
 *
 * @returns PDE.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(X86PDEPAE) pgmShwGetPaePDE(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    const unsigned  iPd     = (GCPtr >> X86_PD_PAE_SHIFT) & X86_PD_PAE_MASK;
    PX86PDPAE       pShwPde = pgmShwGetPaePDPtr(pVCpu, GCPtr);
    if (pShwPde)
        return pShwPde->a[iPd];

    X86PDEPAE ZeroPde = {0};
    return ZeroPde;
}


/**
 * Gets the pointer to the shadow page directory entry for an address, PAE.
 *
 * @returns Pointer to the PDE.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 * @remarks Only used by AssertCR3.
 */
DECLINLINE(PX86PDEPAE) pgmShwGetPaePDEPtr(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    const unsigned iPd     = (GCPtr >> X86_PD_PAE_SHIFT) & X86_PD_PAE_MASK;
    PX86PDPAE      pShwPde = pgmShwGetPaePDPtr(pVCpu, GCPtr);
    AssertReturn(pShwPde, NULL);
    return &pShwPde->a[iPd];
}


/**
 * Gets the shadow page map level-4 pointer.
 *
 * @returns Pointer to the shadow PML4.
 * @param   pVCpu       The cross context virtual CPU structure.
 */
DECLINLINE(PX86PML4) pgmShwGetLongModePML4Ptr(PVMCPUCC pVCpu)
{
    return (PX86PML4)PGMPOOL_PAGE_2_PTR_V2(pVCpu->CTX_SUFF(pVM), pVCpu, pVCpu->pgm.s.CTX_SUFF(pShwPageCR3));
}


/**
 * Gets the shadow page map level-4 entry for the specified address.
 *
 * @returns The entry.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   GCPtr       The address.
 */
DECLINLINE(X86PML4E) pgmShwGetLongModePML4E(PVMCPUCC pVCpu, RTGCPTR GCPtr)
{
    const unsigned  iPml4    = ((RTGCUINTPTR64)GCPtr >> X86_PML4_SHIFT) & X86_PML4_MASK;
    PX86PML4        pShwPml4 = pgmShwGetLongModePML4Ptr(pVCpu);
    if (pShwPml4)
        return pShwPml4->a[iPml4];

    X86PML4E ZeroPml4e = {0};
    return ZeroPml4e;
}


/**
 * Gets the pointer to the specified shadow page map level-4 entry.
 *
 * @returns The entry.
 * @param   pVCpu       The cross context virtual CPU structure.
 * @param   iPml4       The PML4 index.
 */
DECLINLINE(PX86PML4E) pgmShwGetLongModePML4EPtr(PVMCPUCC pVCpu, unsigned int iPml4)
{
    PX86PML4 pShwPml4 = pgmShwGetLongModePML4Ptr(pVCpu);
    if (pShwPml4)
        return &pShwPml4->a[iPml4];
    return NULL;
}


/**
 * Cached physical handler lookup.
 *
 * @returns VBox status code.
 * @retval  VERR_NOT_FOUND if no handler.
 * @param   pVM         The cross context VM structure.
 * @param   GCPhys      The lookup address.
 * @param   ppHandler   Where to return the handler pointer.
 */
DECLINLINE(int) pgmHandlerPhysicalLookup(PVMCC pVM, RTGCPHYS GCPhys, PPGMPHYSHANDLER *ppHandler)
{
    PPGMPHYSHANDLER pHandler = pVM->VMCC_CTX(pgm).s.PhysHandlerAllocator.ptrFromInt(pVM->pgm.s.idxLastPhysHandler);
    if (   pHandler
        && pVM->VMCC_CTX(pgm).s.PhysHandlerAllocator.isPtrRetOkay(pHandler)
        && GCPhys >= pHandler->Key
        && GCPhys <  pHandler->KeyLast
        && pHandler->hType != NIL_PGMPHYSHANDLERTYPE
        && pHandler->hType != 0)

    {
        STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,PhysHandlerLookupHits));
        *ppHandler = pHandler;
        return VINF_SUCCESS;
    }

    STAM_COUNTER_INC(&pVM->pgm.s.Stats.CTX_MID_Z(Stat,PhysHandlerLookupMisses));
    AssertPtrReturn(pVM->VMCC_CTX(pgm).s.pPhysHandlerTree, VERR_PGM_HANDLER_IPE_1);
    int rc = pVM->VMCC_CTX(pgm).s.pPhysHandlerTree->lookup(&pVM->VMCC_CTX(pgm).s.PhysHandlerAllocator, GCPhys, &pHandler);
    if (RT_SUCCESS(rc))
    {
        *ppHandler = pHandler;
        pVM->pgm.s.idxLastPhysHandler = pVM->VMCC_CTX(pgm).s.PhysHandlerAllocator.ptrToInt(pHandler);
        return VINF_SUCCESS;
    }
    *ppHandler = NULL;
    return rc;
}


/**
 * Converts a handle to a pointer.
 *
 * @returns Pointer on success, NULL on failure (asserted).
 * @param   pVM     The cross context VM structure.
 * @param   hType   Physical access handler type handle.
 */
DECLINLINE(PCPGMPHYSHANDLERTYPEINT) pgmHandlerPhysicalTypeHandleToPtr(PVMCC pVM, PGMPHYSHANDLERTYPE hType)
{
#ifdef IN_RING0
    PPGMPHYSHANDLERTYPEINT pType = &pVM->pgmr0.s.aPhysHandlerTypes[hType & PGMPHYSHANDLERTYPE_IDX_MASK];
#elif defined(IN_RING3)
    PPGMPHYSHANDLERTYPEINT pType = &pVM->pgm.s.aPhysHandlerTypes[hType & PGMPHYSHANDLERTYPE_IDX_MASK];
#else
# error "Invalid context"
#endif
    AssertReturn(pType->hType == hType, NULL);
    return pType;
}


/**
 * Converts a handle to a pointer, never returns NULL.
 *
 * @returns Pointer on success, dummy on failure (asserted).
 * @param   pVM     The cross context VM structure.
 * @param   hType   Physical access handler type handle.
 */
DECLINLINE(PCPGMPHYSHANDLERTYPEINT) pgmHandlerPhysicalTypeHandleToPtr2(PVMCC pVM, PGMPHYSHANDLERTYPE hType)
{
#ifdef IN_RING0
    PPGMPHYSHANDLERTYPEINT pType = &pVM->pgmr0.s.aPhysHandlerTypes[hType & PGMPHYSHANDLERTYPE_IDX_MASK];
#elif defined(IN_RING3)
    PPGMPHYSHANDLERTYPEINT pType = &pVM->pgm.s.aPhysHandlerTypes[hType & PGMPHYSHANDLERTYPE_IDX_MASK];
#else
# error "Invalid context"
#endif
    AssertReturn(pType->hType == hType, &g_pgmHandlerPhysicalDummyType);
    return pType;
}


/**
 * Internal worker for finding a 'in-use' shadow page give by it's physical address.
 *
 * @returns Pointer to the shadow page structure.
 * @param   pPool       The pool.
 * @param   idx         The pool page index.
 */
DECLINLINE(PPGMPOOLPAGE) pgmPoolGetPageByIdx(PPGMPOOL pPool, unsigned idx)
{
    AssertFatalMsg(idx >= PGMPOOL_IDX_FIRST && idx < pPool->cCurPages, ("idx=%d\n", idx));
    return &pPool->aPages[idx];
}


/**
 * Clear references to guest physical memory.
 *
 * @param   pPool       The pool.
 * @param   pPoolPage   The pool page.
 * @param   pPhysPage   The physical guest page tracking structure.
 * @param   iPte        Shadow PTE index
 */
DECLINLINE(void) pgmTrackDerefGCPhys(PPGMPOOL pPool, PPGMPOOLPAGE pPoolPage, PPGMPAGE pPhysPage, uint16_t iPte)
{
    /*
     * Just deal with the simple case here.
     */
#ifdef VBOX_STRICT
    PVMCC pVM = pPool->CTX_SUFF(pVM); NOREF(pVM);
#endif
#ifdef LOG_ENABLED
    const unsigned uOrg = PGM_PAGE_GET_TRACKING(pPhysPage);
#endif
    const unsigned cRefs = PGM_PAGE_GET_TD_CREFS(pPhysPage);
    if (cRefs == 1)
    {
        Assert(pPoolPage->idx == PGM_PAGE_GET_TD_IDX(pPhysPage));
        Assert(iPte == PGM_PAGE_GET_PTE_INDEX(pPhysPage));
        /* Invalidate the tracking data. */
        PGM_PAGE_SET_TRACKING(pVM, pPhysPage, 0);
    }
    else
        pgmPoolTrackPhysExtDerefGCPhys(pPool, pPoolPage, pPhysPage, iPte);
    Log2(("pgmTrackDerefGCPhys: %x -> %x pPhysPage=%R[pgmpage]\n", uOrg, PGM_PAGE_GET_TRACKING(pPhysPage), pPhysPage ));
}


/**
 * Moves the page to the head of the age list.
 *
 * This is done when the cached page is used in one way or another.
 *
 * @param   pPool       The pool.
 * @param   pPage       The cached page.
 */
DECLINLINE(void) pgmPoolCacheUsed(PPGMPOOL pPool, PPGMPOOLPAGE pPage)
{
    PGM_LOCK_ASSERT_OWNER(pPool->CTX_SUFF(pVM));

    /*
     * Move to the head of the age list.
     */
    if (pPage->iAgePrev != NIL_PGMPOOL_IDX)
    {
        /* unlink */
        pPool->aPages[pPage->iAgePrev].iAgeNext = pPage->iAgeNext;
        if (pPage->iAgeNext != NIL_PGMPOOL_IDX)
            pPool->aPages[pPage->iAgeNext].iAgePrev = pPage->iAgePrev;
        else
            pPool->iAgeTail = pPage->iAgePrev;

        /* insert at head */
        pPage->iAgePrev = NIL_PGMPOOL_IDX;
        pPage->iAgeNext = pPool->iAgeHead;
        Assert(pPage->iAgeNext != NIL_PGMPOOL_IDX); /* we would've already been head then */
        pPool->iAgeHead = pPage->idx;
        pPool->aPages[pPage->iAgeNext].iAgePrev = pPage->idx;
    }
}


/**
 * Locks a page to prevent flushing (important for cr3 root pages or shadow pae pd pages).
 *
 * @param   pPool       The pool.
 * @param   pPage       PGM pool page
 */
DECLINLINE(void) pgmPoolLockPage(PPGMPOOL pPool, PPGMPOOLPAGE pPage)
{
    PGM_LOCK_ASSERT_OWNER(pPool->CTX_SUFF(pVM)); NOREF(pPool);
    ASMAtomicIncU32(&pPage->cLocked);
}


/**
 * Unlocks a page to allow flushing again
 *
 * @param   pPool       The pool.
 * @param   pPage       PGM pool page
 */
DECLINLINE(void) pgmPoolUnlockPage(PPGMPOOL pPool, PPGMPOOLPAGE pPage)
{
    PGM_LOCK_ASSERT_OWNER(pPool->CTX_SUFF(pVM)); NOREF(pPool);
    Assert(pPage->cLocked);
    ASMAtomicDecU32(&pPage->cLocked);
}


/**
 * Checks if the page is locked (e.g. the active CR3 or one of the four PDs of a PAE PDPT)
 *
 * @returns VBox status code.
 * @param   pPage       PGM pool page
 */
DECLINLINE(bool) pgmPoolIsPageLocked(PPGMPOOLPAGE pPage)
{
    if (pPage->cLocked)
    {
        LogFlow(("pgmPoolIsPageLocked found root page %d\n", pPage->enmKind));
        if (pPage->cModifications)
            pPage->cModifications = 1; /* reset counter (can't use 0, or else it will be reinserted in the modified list) */
        return true;
    }
    return false;
}


/**
 * Check if the specified page is dirty (not write monitored)
 *
 * @return dirty or not
 * @param   pVM             The cross context VM structure.
 * @param   GCPhys          Guest physical address
 */
DECLINLINE(bool) pgmPoolIsDirtyPage(PVMCC pVM, RTGCPHYS GCPhys)
{
    PPGMPOOL pPool = pVM->pgm.s.CTX_SUFF(pPool);
    PGM_LOCK_ASSERT_OWNER(pVM);
    if (!pPool->cDirtyPages)
        return false;
    return pgmPoolIsDirtyPageSlow(pVM, GCPhys);
}


/** @} */

#endif /* !VMM_INCLUDED_SRC_include_PGMInline_h */