blob: 1b885e24ee17952a6bef341732c434c348e8d59c [file] [log] [blame]
/*
* QEMU Guest Agent win32 VSS Provider implementations
*
* Copyright Hitachi Data Systems Corp. 2013
*
* Authors:
* Tomoki Sekiyama <tomoki.sekiyama@hds.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#include "qemu/osdep.h"
#include "vss-common.h"
#ifdef HAVE_VSS_SDK
#include <vscoordint.h>
#else
#include <vsadmin.h>
#endif
#include <vsprov.h>
#define VSS_TIMEOUT_MSEC (60*1000)
static long g_nComObjsInUse;
HINSTANCE g_hinstDll;
/* VSS common GUID's */
const CLSID CLSID_VSSCoordinator = { 0xE579AB5F, 0x1CC4, 0x44b4,
{0xBE, 0xD9, 0xDE, 0x09, 0x91, 0xFF, 0x06, 0x23} };
const IID IID_IVssAdmin = { 0x77ED5996, 0x2F63, 0x11d3,
{0x8A, 0x39, 0x00, 0xC0, 0x4F, 0x72, 0xD8, 0xE3} };
const IID IID_IVssHardwareSnapshotProvider = { 0x9593A157, 0x44E9, 0x4344,
{0xBB, 0xEB, 0x44, 0xFB, 0xF9, 0xB0, 0x6B, 0x10} };
const IID IID_IVssSoftwareSnapshotProvider = { 0x609e123e, 0x2c5a, 0x44d3,
{0x8f, 0x01, 0x0b, 0x1d, 0x9a, 0x47, 0xd1, 0xff} };
const IID IID_IVssProviderCreateSnapshotSet = { 0x5F894E5B, 0x1E39, 0x4778,
{0x8E, 0x23, 0x9A, 0xBA, 0xD9, 0xF0, 0xE0, 0x8C} };
const IID IID_IVssProviderNotifications = { 0xE561901F, 0x03A5, 0x4afe,
{0x86, 0xD0, 0x72, 0xBA, 0xEE, 0xCE, 0x70, 0x04} };
const IID IID_IVssEnumObject = { 0xAE1C7110, 0x2F60, 0x11d3,
{0x8A, 0x39, 0x00, 0xC0, 0x4F, 0x72, 0xD8, 0xE3} };
void LockModule(BOOL lock)
{
if (lock) {
InterlockedIncrement(&g_nComObjsInUse);
} else {
InterlockedDecrement(&g_nComObjsInUse);
}
}
/* Empty enumerator for VssObject */
class CQGAVSSEnumObject : public IVssEnumObject
{
public:
STDMETHODIMP QueryInterface(REFIID riid, void **ppObj);
STDMETHODIMP_(ULONG) AddRef();
STDMETHODIMP_(ULONG) Release();
/* IVssEnumObject Methods */
STDMETHODIMP Next(
ULONG celt, VSS_OBJECT_PROP *rgelt, ULONG *pceltFetched);
STDMETHODIMP Skip(ULONG celt);
STDMETHODIMP Reset(void);
STDMETHODIMP Clone(IVssEnumObject **ppenum);
/* CQGAVSSEnumObject Methods */
CQGAVSSEnumObject();
~CQGAVSSEnumObject();
private:
long m_nRefCount;
};
CQGAVSSEnumObject::CQGAVSSEnumObject()
{
m_nRefCount = 0;
LockModule(TRUE);
}
CQGAVSSEnumObject::~CQGAVSSEnumObject()
{
LockModule(FALSE);
}
STDMETHODIMP CQGAVSSEnumObject::QueryInterface(REFIID riid, void **ppObj)
{
if (riid == IID_IUnknown || riid == IID_IVssEnumObject) {
*ppObj = static_cast<void*>(static_cast<IVssEnumObject*>(this));
AddRef();
return S_OK;
}
*ppObj = NULL;
return E_NOINTERFACE;
}
STDMETHODIMP_(ULONG) CQGAVSSEnumObject::AddRef()
{
return InterlockedIncrement(&m_nRefCount);
}
STDMETHODIMP_(ULONG) CQGAVSSEnumObject::Release()
{
long nRefCount = InterlockedDecrement(&m_nRefCount);
if (m_nRefCount == 0) {
delete this;
}
return nRefCount;
}
STDMETHODIMP CQGAVSSEnumObject::Next(
ULONG celt, VSS_OBJECT_PROP *rgelt, ULONG *pceltFetched)
{
*pceltFetched = 0;
return S_FALSE;
}
STDMETHODIMP CQGAVSSEnumObject::Skip(ULONG celt)
{
return S_FALSE;
}
STDMETHODIMP CQGAVSSEnumObject::Reset(void)
{
return S_OK;
}
STDMETHODIMP CQGAVSSEnumObject::Clone(IVssEnumObject **ppenum)
{
return E_NOTIMPL;
}
/* QGAVssProvider */
class CQGAVssProvider :
public IVssSoftwareSnapshotProvider,
public IVssProviderCreateSnapshotSet,
public IVssProviderNotifications
{
public:
STDMETHODIMP QueryInterface(REFIID riid, void **ppObj);
STDMETHODIMP_(ULONG) AddRef();
STDMETHODIMP_(ULONG) Release();
/* IVssSoftwareSnapshotProvider Methods */
STDMETHODIMP SetContext(LONG lContext);
STDMETHODIMP GetSnapshotProperties(
VSS_ID SnapshotId, VSS_SNAPSHOT_PROP *pProp);
STDMETHODIMP Query(
VSS_ID QueriedObjectId, VSS_OBJECT_TYPE eQueriedObjectType,
VSS_OBJECT_TYPE eReturnedObjectsType, IVssEnumObject **ppEnum);
STDMETHODIMP DeleteSnapshots(
VSS_ID SourceObjectId, VSS_OBJECT_TYPE eSourceObjectType,
BOOL bForceDelete, LONG *plDeletedSnapshots,
VSS_ID *pNondeletedSnapshotID);
STDMETHODIMP BeginPrepareSnapshot(
VSS_ID SnapshotSetId, VSS_ID SnapshotId,
VSS_PWSZ pwszVolumeName, LONG lNewContext);
STDMETHODIMP IsVolumeSupported(
VSS_PWSZ pwszVolumeName, BOOL *pbSupportedByThisProvider);
STDMETHODIMP IsVolumeSnapshotted(
VSS_PWSZ pwszVolumeName, BOOL *pbSnapshotsPresent,
LONG *plSnapshotCompatibility);
STDMETHODIMP SetSnapshotProperty(
VSS_ID SnapshotId, VSS_SNAPSHOT_PROPERTY_ID eSnapshotPropertyId,
VARIANT vProperty);
STDMETHODIMP RevertToSnapshot(VSS_ID SnapshotId);
STDMETHODIMP QueryRevertStatus(VSS_PWSZ pwszVolume, IVssAsync **ppAsync);
/* IVssProviderCreateSnapshotSet Methods */
STDMETHODIMP EndPrepareSnapshots(VSS_ID SnapshotSetId);
STDMETHODIMP PreCommitSnapshots(VSS_ID SnapshotSetId);
STDMETHODIMP CommitSnapshots(VSS_ID SnapshotSetId);
STDMETHODIMP PostCommitSnapshots(
VSS_ID SnapshotSetId, LONG lSnapshotsCount);
STDMETHODIMP PreFinalCommitSnapshots(VSS_ID SnapshotSetId);
STDMETHODIMP PostFinalCommitSnapshots(VSS_ID SnapshotSetId);
STDMETHODIMP AbortSnapshots(VSS_ID SnapshotSetId);
/* IVssProviderNotifications Methods */
STDMETHODIMP OnLoad(IUnknown *pCallback);
STDMETHODIMP OnUnload(BOOL bForceUnload);
/* CQGAVssProvider Methods */
CQGAVssProvider();
~CQGAVssProvider();
private:
long m_nRefCount;
};
CQGAVssProvider::CQGAVssProvider()
{
m_nRefCount = 0;
LockModule(TRUE);
}
CQGAVssProvider::~CQGAVssProvider()
{
LockModule(FALSE);
}
STDMETHODIMP CQGAVssProvider::QueryInterface(REFIID riid, void **ppObj)
{
if (riid == IID_IUnknown) {
*ppObj = static_cast<void*>(this);
AddRef();
return S_OK;
}
if (riid == IID_IVssSoftwareSnapshotProvider) {
*ppObj = static_cast<void*>(
static_cast<IVssSoftwareSnapshotProvider*>(this));
AddRef();
return S_OK;
}
if (riid == IID_IVssProviderCreateSnapshotSet) {
*ppObj = static_cast<void*>(
static_cast<IVssProviderCreateSnapshotSet*>(this));
AddRef();
return S_OK;
}
if (riid == IID_IVssProviderNotifications) {
*ppObj = static_cast<void*>(
static_cast<IVssProviderNotifications*>(this));
AddRef();
return S_OK;
}
*ppObj = NULL;
return E_NOINTERFACE;
}
STDMETHODIMP_(ULONG) CQGAVssProvider::AddRef()
{
return InterlockedIncrement(&m_nRefCount);
}
STDMETHODIMP_(ULONG) CQGAVssProvider::Release()
{
long nRefCount = InterlockedDecrement(&m_nRefCount);
if (m_nRefCount == 0) {
delete this;
}
return nRefCount;
}
/*
* IVssSoftwareSnapshotProvider methods
*/
STDMETHODIMP CQGAVssProvider::SetContext(LONG lContext)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::GetSnapshotProperties(
VSS_ID SnapshotId, VSS_SNAPSHOT_PROP *pProp)
{
return VSS_E_OBJECT_NOT_FOUND;
}
STDMETHODIMP CQGAVssProvider::Query(
VSS_ID QueriedObjectId, VSS_OBJECT_TYPE eQueriedObjectType,
VSS_OBJECT_TYPE eReturnedObjectsType, IVssEnumObject **ppEnum)
{
try {
*ppEnum = new CQGAVSSEnumObject;
} catch (...) {
return E_OUTOFMEMORY;
}
(*ppEnum)->AddRef();
return S_OK;
}
STDMETHODIMP CQGAVssProvider::DeleteSnapshots(
VSS_ID SourceObjectId, VSS_OBJECT_TYPE eSourceObjectType,
BOOL bForceDelete, LONG *plDeletedSnapshots, VSS_ID *pNondeletedSnapshotID)
{
*plDeletedSnapshots = 0;
*pNondeletedSnapshotID = SourceObjectId;
return S_OK;
}
STDMETHODIMP CQGAVssProvider::BeginPrepareSnapshot(
VSS_ID SnapshotSetId, VSS_ID SnapshotId,
VSS_PWSZ pwszVolumeName, LONG lNewContext)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::IsVolumeSupported(
VSS_PWSZ pwszVolumeName, BOOL *pbSupportedByThisProvider)
{
HANDLE hEventFrozen;
/* Check if a requester is qemu-ga by whether an event is created */
hEventFrozen = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_FROZEN);
if (!hEventFrozen) {
*pbSupportedByThisProvider = FALSE;
return S_OK;
}
CloseHandle(hEventFrozen);
*pbSupportedByThisProvider = TRUE;
return S_OK;
}
STDMETHODIMP CQGAVssProvider::IsVolumeSnapshotted(VSS_PWSZ pwszVolumeName,
BOOL *pbSnapshotsPresent, LONG *plSnapshotCompatibility)
{
*pbSnapshotsPresent = FALSE;
*plSnapshotCompatibility = 0;
return S_OK;
}
STDMETHODIMP CQGAVssProvider::SetSnapshotProperty(VSS_ID SnapshotId,
VSS_SNAPSHOT_PROPERTY_ID eSnapshotPropertyId, VARIANT vProperty)
{
return E_NOTIMPL;
}
STDMETHODIMP CQGAVssProvider::RevertToSnapshot(VSS_ID SnapshotId)
{
return E_NOTIMPL;
}
STDMETHODIMP CQGAVssProvider::QueryRevertStatus(
VSS_PWSZ pwszVolume, IVssAsync **ppAsync)
{
return E_NOTIMPL;
}
/*
* IVssProviderCreateSnapshotSet methods
*/
STDMETHODIMP CQGAVssProvider::EndPrepareSnapshots(VSS_ID SnapshotSetId)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::PreCommitSnapshots(VSS_ID SnapshotSetId)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::CommitSnapshots(VSS_ID SnapshotSetId)
{
HRESULT hr = S_OK;
HANDLE hEventFrozen, hEventThaw, hEventTimeout;
hEventFrozen = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_FROZEN);
if (!hEventFrozen) {
return E_FAIL;
}
hEventThaw = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_THAW);
if (!hEventThaw) {
CloseHandle(hEventFrozen);
return E_FAIL;
}
hEventTimeout = OpenEvent(EVENT_ALL_ACCESS, FALSE, EVENT_NAME_TIMEOUT);
if (!hEventTimeout) {
CloseHandle(hEventFrozen);
CloseHandle(hEventThaw);
return E_FAIL;
}
/* Send event to qemu-ga to notify filesystem is frozen */
SetEvent(hEventFrozen);
/* Wait until the snapshot is taken by the host. */
if (WaitForSingleObject(hEventThaw, VSS_TIMEOUT_MSEC) != WAIT_OBJECT_0) {
/* Send event to qemu-ga to notify the provider is timed out */
SetEvent(hEventTimeout);
}
CloseHandle(hEventThaw);
CloseHandle(hEventFrozen);
CloseHandle(hEventTimeout);
return hr;
}
STDMETHODIMP CQGAVssProvider::PostCommitSnapshots(
VSS_ID SnapshotSetId, LONG lSnapshotsCount)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::PreFinalCommitSnapshots(VSS_ID SnapshotSetId)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::PostFinalCommitSnapshots(VSS_ID SnapshotSetId)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::AbortSnapshots(VSS_ID SnapshotSetId)
{
return S_OK;
}
/*
* IVssProviderNotifications methods
*/
STDMETHODIMP CQGAVssProvider::OnLoad(IUnknown *pCallback)
{
return S_OK;
}
STDMETHODIMP CQGAVssProvider::OnUnload(BOOL bForceUnload)
{
return S_OK;
}
/*
* CQGAVssProviderFactory class
*/
class CQGAVssProviderFactory : public IClassFactory
{
public:
STDMETHODIMP QueryInterface(REFIID riid, void **ppv);
STDMETHODIMP_(ULONG) AddRef();
STDMETHODIMP_(ULONG) Release();
STDMETHODIMP CreateInstance(
IUnknown *pUnknownOuter, REFIID iid, void **ppv);
STDMETHODIMP LockServer(BOOL lock) { return E_NOTIMPL; }
CQGAVssProviderFactory();
~CQGAVssProviderFactory();
private:
long m_nRefCount;
};
CQGAVssProviderFactory::CQGAVssProviderFactory()
{
m_nRefCount = 0;
LockModule(TRUE);
}
CQGAVssProviderFactory::~CQGAVssProviderFactory()
{
LockModule(FALSE);
}
STDMETHODIMP CQGAVssProviderFactory::QueryInterface(REFIID riid, void **ppv)
{
if (riid == IID_IUnknown || riid == IID_IClassFactory) {
*ppv = static_cast<void*>(this);
AddRef();
return S_OK;
}
*ppv = NULL;
return E_NOINTERFACE;
}
STDMETHODIMP_(ULONG) CQGAVssProviderFactory::AddRef()
{
return InterlockedIncrement(&m_nRefCount);
}
STDMETHODIMP_(ULONG) CQGAVssProviderFactory::Release()
{
long nRefCount = InterlockedDecrement(&m_nRefCount);
if (m_nRefCount == 0) {
delete this;
}
return nRefCount;
}
STDMETHODIMP CQGAVssProviderFactory::CreateInstance(
IUnknown *pUnknownOuter, REFIID iid, void **ppv)
{
CQGAVssProvider *pObj;
if (pUnknownOuter) {
return CLASS_E_NOAGGREGATION;
}
try {
pObj = new CQGAVssProvider;
} catch (...) {
return E_OUTOFMEMORY;
}
HRESULT hr = pObj->QueryInterface(iid, ppv);
if (FAILED(hr)) {
delete pObj;
}
return hr;
}
/*
* DLL functions
*/
STDAPI DllGetClassObject(REFCLSID rclsid, REFIID riid, LPVOID *ppv)
{
CQGAVssProviderFactory *factory;
try {
factory = new CQGAVssProviderFactory;
} catch (...) {
return E_OUTOFMEMORY;
}
factory->AddRef();
HRESULT hr = factory->QueryInterface(riid, ppv);
factory->Release();
return hr;
}
STDAPI DllCanUnloadNow()
{
return g_nComObjsInUse == 0 ? S_OK : S_FALSE;
}
EXTERN_C
BOOL WINAPI DllMain(HINSTANCE hinstDll, DWORD dwReason, LPVOID lpReserved)
{
if (dwReason == DLL_PROCESS_ATTACH) {
g_hinstDll = hinstDll;
DisableThreadLibraryCalls(hinstDll);
}
return TRUE;
}