/* $Id: PGMSharedPage.cpp 98103 2023-01-17 14:15:46Z vboxsync $ */ /** @file * PGM - Page Manager and Monitor, Shared page handling */ /* * Copyright (C) 2006-2023 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 . * * SPDX-License-Identifier: GPL-3.0-only */ /********************************************************************************************************************************* * Header Files * *********************************************************************************************************************************/ #define LOG_GROUP LOG_GROUP_PGM_SHARED #define VBOX_WITHOUT_PAGING_BIT_FIELDS /* 64-bit bitfields are just asking for trouble. See @bugref{9841} and others. */ #include #include #include #include "PGMInternal.h" #include #include #include #include #include #include #include #include #include #include #include "PGMInline.h" #ifdef VBOX_WITH_PAGE_SHARING /********************************************************************************************************************************* * Global Variables * *********************************************************************************************************************************/ # ifdef VBOX_STRICT /** Keep a copy of all registered shared modules for the .pgmcheckduppages debugger command. */ static PGMMREGISTERSHAREDMODULEREQ g_apSharedModules[512] = {0}; static unsigned g_cSharedModules = 0; # endif /* VBOX_STRICT */ /** * Registers a new shared module for the VM * * @returns VBox status code. * @param pVM The cross context VM structure. * @param enmGuestOS Guest OS type. * @param pszModuleName Module name. * @param pszVersion Module version. * @param GCBaseAddr Module base address. * @param cbModule Module size. * @param cRegions Number of shared region descriptors. * @param paRegions Shared region(s). * * @todo This should be a GMMR3 call. No need to involve GMM here. */ VMMR3DECL(int) PGMR3SharedModuleRegister(PVM pVM, VBOXOSFAMILY enmGuestOS, char *pszModuleName, char *pszVersion, RTGCPTR GCBaseAddr, uint32_t cbModule, uint32_t cRegions, VMMDEVSHAREDREGIONDESC const *paRegions) { Log(("PGMR3SharedModuleRegister family=%d name=%s version=%s base=%RGv size=%x cRegions=%d\n", enmGuestOS, pszModuleName, pszVersion, GCBaseAddr, cbModule, cRegions)); /* * Sanity check. */ AssertReturn(cRegions <= VMMDEVSHAREDREGIONDESC_MAX, VERR_INVALID_PARAMETER); if (!pVM->pgm.s.fPageFusionAllowed) return VERR_NOT_SUPPORTED; /* * Allocate and initialize a GMM request. */ PGMMREGISTERSHAREDMODULEREQ pReq; pReq = (PGMMREGISTERSHAREDMODULEREQ)RTMemAllocZ(RT_UOFFSETOF_DYN(GMMREGISTERSHAREDMODULEREQ, aRegions[cRegions])); AssertReturn(pReq, VERR_NO_MEMORY); pReq->enmGuestOS = enmGuestOS; pReq->GCBaseAddr = GCBaseAddr; pReq->cbModule = cbModule; pReq->cRegions = cRegions; for (uint32_t i = 0; i < cRegions; i++) pReq->aRegions[i] = paRegions[i]; int rc = RTStrCopy(pReq->szName, sizeof(pReq->szName), pszModuleName); if (RT_SUCCESS(rc)) { rc = RTStrCopy(pReq->szVersion, sizeof(pReq->szVersion), pszVersion); if (RT_SUCCESS(rc)) { /* * Issue the request. In strict builds, do some local tracking. */ pgmR3PhysAssertSharedPageChecksums(pVM); rc = GMMR3RegisterSharedModule(pVM, pReq); if (RT_SUCCESS(rc)) rc = pReq->rc; AssertMsg(rc == VINF_SUCCESS || rc == VINF_GMM_SHARED_MODULE_ALREADY_REGISTERED, ("%Rrc\n", rc)); # ifdef VBOX_STRICT if ( rc == VINF_SUCCESS && g_cSharedModules < RT_ELEMENTS(g_apSharedModules)) { unsigned i; for (i = 0; i < RT_ELEMENTS(g_apSharedModules); i++) if (g_apSharedModules[i] == NULL) { size_t const cbSharedModule = RT_UOFFSETOF_DYN(GMMREGISTERSHAREDMODULEREQ, aRegions[cRegions]); g_apSharedModules[i] = (PGMMREGISTERSHAREDMODULEREQ)RTMemDup(pReq, cbSharedModule); g_cSharedModules++; break; } Assert(i < RT_ELEMENTS(g_apSharedModules)); } # endif /* VBOX_STRICT */ if (RT_SUCCESS(rc)) rc = VINF_SUCCESS; } } RTMemFree(pReq); return rc; } /** * Unregisters a shared module for the VM * * @returns VBox status code. * @param pVM The cross context VM structure. * @param pszModuleName Module name. * @param pszVersion Module version. * @param GCBaseAddr Module base address. * @param cbModule Module size. * * @todo This should be a GMMR3 call. No need to involve GMM here. */ VMMR3DECL(int) PGMR3SharedModuleUnregister(PVM pVM, char *pszModuleName, char *pszVersion, RTGCPTR GCBaseAddr, uint32_t cbModule) { Log(("PGMR3SharedModuleUnregister name=%s version=%s base=%RGv size=%x\n", pszModuleName, pszVersion, GCBaseAddr, cbModule)); AssertMsgReturn(cbModule > 0 && cbModule < _1G, ("%u\n", cbModule), VERR_OUT_OF_RANGE); if (!pVM->pgm.s.fPageFusionAllowed) return VERR_NOT_SUPPORTED; /* * Forward the request to GMM (ring-0). */ PGMMUNREGISTERSHAREDMODULEREQ pReq = (PGMMUNREGISTERSHAREDMODULEREQ)RTMemAlloc(sizeof(*pReq)); AssertReturn(pReq, VERR_NO_MEMORY); pReq->GCBaseAddr = GCBaseAddr; pReq->u32Alignment = 0; pReq->cbModule = cbModule; int rc = RTStrCopy(pReq->szName, sizeof(pReq->szName), pszModuleName); if (RT_SUCCESS(rc)) { rc = RTStrCopy(pReq->szVersion, sizeof(pReq->szVersion), pszVersion); if (RT_SUCCESS(rc)) { pgmR3PhysAssertSharedPageChecksums(pVM); rc = GMMR3UnregisterSharedModule(pVM, pReq); pgmR3PhysAssertSharedPageChecksums(pVM); # ifdef VBOX_STRICT /* * Update our local tracking. */ for (unsigned i = 0; i < g_cSharedModules; i++) { if ( g_apSharedModules[i] && !strcmp(g_apSharedModules[i]->szName, pszModuleName) && !strcmp(g_apSharedModules[i]->szVersion, pszVersion)) { RTMemFree(g_apSharedModules[i]); g_apSharedModules[i] = NULL; g_cSharedModules--; break; } } # endif /* VBOX_STRICT */ } } RTMemFree(pReq); return rc; } /** * Rendezvous callback that will be called once. * * @returns VBox strict status code. * @param pVM The cross context VM structure. * @param pVCpu The cross context virtual CPU structure of the calling EMT. * @param pvUser Pointer to a VMCPUID with the requester's ID. */ static DECLCALLBACK(VBOXSTRICTRC) pgmR3SharedModuleRegRendezvous(PVM pVM, PVMCPU pVCpu, void *pvUser) { VMCPUID idCpu = *(VMCPUID *)pvUser; /* Execute on the VCPU that issued the original request to make sure we're in the right cr3 context. */ if (pVCpu->idCpu != idCpu) { Assert(pVM->cCpus > 1); return VINF_SUCCESS; } /* Flush all pending handy page operations before changing any shared page assignments. */ int rc = PGMR3PhysAllocateHandyPages(pVM); AssertRC(rc); /* * Lock it here as we can't deal with busy locks in this ring-0 path. */ LogFlow(("pgmR3SharedModuleRegRendezvous: start (%d)\n", pVM->pgm.s.cSharedPages)); PGM_LOCK_VOID(pVM); pgmR3PhysAssertSharedPageChecksums(pVM); rc = GMMR3CheckSharedModules(pVM); pgmR3PhysAssertSharedPageChecksums(pVM); PGM_UNLOCK(pVM); AssertLogRelRC(rc); LogFlow(("pgmR3SharedModuleRegRendezvous: done (%d)\n", pVM->pgm.s.cSharedPages)); return rc; } /** * Shared module check helper (called on the way out). * * @param pVM The cross context VM structure. * @param idCpu VCPU id. */ static DECLCALLBACK(void) pgmR3CheckSharedModulesHelper(PVM pVM, VMCPUID idCpu) { /* We must stall other VCPUs as we'd otherwise have to send IPI flush commands for every single change we make. */ STAM_REL_PROFILE_START(&pVM->pgm.s.StatShModCheck, a); int rc = VMMR3EmtRendezvous(pVM, VMMEMTRENDEZVOUS_FLAGS_TYPE_ALL_AT_ONCE, pgmR3SharedModuleRegRendezvous, &idCpu); AssertRCSuccess(rc); STAM_REL_PROFILE_STOP(&pVM->pgm.s.StatShModCheck, a); } /** * Check all registered modules for changes. * * @returns VBox status code. * @param pVM The cross context VM structure. */ VMMR3DECL(int) PGMR3SharedModuleCheckAll(PVM pVM) { if (!pVM->pgm.s.fPageFusionAllowed) return VERR_NOT_SUPPORTED; /* Queue the actual registration as we are under the IOM lock right now. Perform this operation on the way out. */ return VMR3ReqCallNoWait(pVM, VMCPUID_ANY_QUEUE, (PFNRT)pgmR3CheckSharedModulesHelper, 2, pVM, VMMGetCpuId(pVM)); } # ifdef DEBUG /** * Query the state of a page in a shared module * * @returns VBox status code. * @param pVM The cross context VM structure. * @param GCPtrPage Page address. * @param pfShared Shared status (out). * @param pfPageFlags Page flags (out). */ VMMR3DECL(int) PGMR3SharedModuleGetPageState(PVM pVM, RTGCPTR GCPtrPage, bool *pfShared, uint64_t *pfPageFlags) { /* Debug only API for the page fusion testcase. */ PGMPTWALK Walk; PGM_LOCK_VOID(pVM); int rc = PGMGstGetPage(VMMGetCpu(pVM), GCPtrPage, &Walk); switch (rc) { case VINF_SUCCESS: { PPGMPAGE pPage = pgmPhysGetPage(pVM, Walk.GCPhys); if (pPage) { *pfShared = PGM_PAGE_IS_SHARED(pPage); *pfPageFlags = Walk.fEffective; } else rc = VERR_PGM_INVALID_GC_PHYSICAL_ADDRESS; break; } case VERR_PAGE_NOT_PRESENT: case VERR_PAGE_TABLE_NOT_PRESENT: case VERR_PAGE_MAP_LEVEL4_NOT_PRESENT: case VERR_PAGE_DIRECTORY_PTR_NOT_PRESENT: *pfShared = false; *pfPageFlags = 0; rc = VINF_SUCCESS; break; default: break; } PGM_UNLOCK(pVM); return rc; } # endif /* DEBUG */ # ifdef VBOX_STRICT /** * @callback_method_impl{FNDBGCCMD, The '.pgmcheckduppages' command.} */ DECLCALLBACK(int) pgmR3CmdCheckDuplicatePages(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PUVM pUVM, PCDBGCVAR paArgs, unsigned cArgs) { unsigned cBallooned = 0; unsigned cShared = 0; unsigned cZero = 0; unsigned cUnique = 0; unsigned cDuplicate = 0; unsigned cAllocZero = 0; unsigned cPages = 0; NOREF(pCmd); NOREF(paArgs); NOREF(cArgs); PVM pVM = pUVM->pVM; VM_ASSERT_VALID_EXT_RETURN(pVM, VERR_INVALID_VM_HANDLE); PGM_LOCK_VOID(pVM); for (PPGMRAMRANGE pRam = pVM->pgm.s.pRamRangesXR3; pRam; pRam = pRam->pNextR3) { PPGMPAGE pPage = &pRam->aPages[0]; RTGCPHYS GCPhys = pRam->GCPhys; uint32_t cLeft = pRam->cb >> GUEST_PAGE_SHIFT; while (cLeft-- > 0) { if (PGM_PAGE_GET_TYPE(pPage) == PGMPAGETYPE_RAM) { switch (PGM_PAGE_GET_STATE(pPage)) { case PGM_PAGE_STATE_ZERO: cZero++; break; case PGM_PAGE_STATE_BALLOONED: cBallooned++; break; case PGM_PAGE_STATE_SHARED: cShared++; break; case PGM_PAGE_STATE_ALLOCATED: case PGM_PAGE_STATE_WRITE_MONITORED: { /* Check if the page was allocated, but completely zero. */ PGMPAGEMAPLOCK PgMpLck; const void *pvPage; int rc = pgmPhysGCPhys2CCPtrInternalReadOnly(pVM, pPage, GCPhys, &pvPage, &PgMpLck); if ( RT_SUCCESS(rc) && ASMMemIsZero(pvPage, GUEST_PAGE_SIZE)) cAllocZero++; else if (GMMR3IsDuplicatePage(pVM, PGM_PAGE_GET_PAGEID(pPage))) cDuplicate++; else cUnique++; if (RT_SUCCESS(rc)) pgmPhysReleaseInternalPageMappingLock(pVM, &PgMpLck); break; } default: AssertFailed(); break; } } /* next */ pPage++; GCPhys += GUEST_PAGE_SIZE; cPages++; /* Give some feedback for every processed megabyte. */ if ((cPages & 0x7f) == 0) pCmdHlp->pfnPrintf(pCmdHlp, NULL, "."); } } PGM_UNLOCK(pVM); pCmdHlp->pfnPrintf(pCmdHlp, NULL, "\nNumber of zero pages %08x (%d MB)\n", cZero, cZero / 256); pCmdHlp->pfnPrintf(pCmdHlp, NULL, "Number of alloczero pages %08x (%d MB)\n", cAllocZero, cAllocZero / 256); pCmdHlp->pfnPrintf(pCmdHlp, NULL, "Number of ballooned pages %08x (%d MB)\n", cBallooned, cBallooned / 256); pCmdHlp->pfnPrintf(pCmdHlp, NULL, "Number of shared pages %08x (%d MB)\n", cShared, cShared / 256); pCmdHlp->pfnPrintf(pCmdHlp, NULL, "Number of unique pages %08x (%d MB)\n", cUnique, cUnique / 256); pCmdHlp->pfnPrintf(pCmdHlp, NULL, "Number of duplicate pages %08x (%d MB)\n", cDuplicate, cDuplicate / 256); return VINF_SUCCESS; } /** * @callback_method_impl{FNDBGCCMD, The '.pgmsharedmodules' command.} */ DECLCALLBACK(int) pgmR3CmdShowSharedModules(PCDBGCCMD pCmd, PDBGCCMDHLP pCmdHlp, PUVM pUVM, PCDBGCVAR paArgs, unsigned cArgs) { NOREF(pCmd); NOREF(paArgs); NOREF(cArgs); PVM pVM = pUVM->pVM; VM_ASSERT_VALID_EXT_RETURN(pVM, VERR_INVALID_VM_HANDLE); PGM_LOCK_VOID(pVM); for (unsigned i = 0; i < RT_ELEMENTS(g_apSharedModules); i++) { if (g_apSharedModules[i]) { pCmdHlp->pfnPrintf(pCmdHlp, NULL, "Shared module %s (%s):\n", g_apSharedModules[i]->szName, g_apSharedModules[i]->szVersion); for (unsigned j = 0; j < g_apSharedModules[i]->cRegions; j++) pCmdHlp->pfnPrintf(pCmdHlp, NULL, "--- Region %d: base %RGv size %x\n", j, g_apSharedModules[i]->aRegions[j].GCRegionAddr, g_apSharedModules[i]->aRegions[j].cbRegion); } } PGM_UNLOCK(pVM); return VINF_SUCCESS; } # endif /* VBOX_STRICT*/ #endif /* VBOX_WITH_PAGE_SHARING */