Implement fetching physical QStorageInfo::blockSize() under Windows

This is implemented in two passes, first we try the older and
always available DeviceIoControl() function. This works most of
the time, though it might fail for example for storage devices
attached via USB. In this case, we try to dynamically load the
newer NtQueryVolumeInformationFile kernel function. Since this
is probably more expensive, we do this as fallback.

[ChangeLog][QtCore][QStorageInfo] The QStorageInfo::blockSize()
will now report the physical block size of a storage device under
Windows. Network mapped drives are not supported.

Fixes: QTBUG-93976
Change-Id: I08b5b879e5bf79c025e2e305196ec5c5fce8b20f
Reviewed-by: Edward Welbourne <edward.welbourne@qt.io>
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>

3 files changed, 239 insertions, 1 deletions

diff --git a/src/corelib/io/qntdll_p.h b/src/corelib/io/qntdll_p.h
new file mode 100644
index 0000000000..caf34ddb5f
--- /dev/null
+++ b/src/corelib/io/qntdll_p.h
@@ -0,0 +1,96 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef QNTDLL_P_H
+#define QNTDLL_P_H
+
+//
+//  W A R N I N G
+//  -------------
+//
+// This file is not part of the Qt API.  It exists purely as an
+// implementation detail.  This header file may change from version to
+// version without notice, or even be removed.
+//
+// We mean it.
+//
+
+#include <winternl.h>
+
+QT_BEGIN_NAMESPACE
+
+// keep the following structure as is, taken from
+// https://docs.microsoft.com/en-us/windows-hardware/drivers/ddi/ntddk/ns-ntddk-_file_fs_sector_size_information
+// Unfortunately we can't include the ntddk.h header, so we duplicate the code here.
+typedef struct _FILE_FS_SECTOR_SIZE_INFORMATION {
+    ULONG LogicalBytesPerSector;
+    ULONG PhysicalBytesPerSectorForAtomicity;
+    ULONG PhysicalBytesPerSectorForPerformance;
+    ULONG FileSystemEffectivePhysicalBytesPerSectorForAtomicity;
+    ULONG Flags;
+    ULONG ByteOffsetForSectorAlignment;
+    ULONG ByteOffsetForPartitionAlignment;
+} FILE_FS_SECTOR_SIZE_INFORMATION, *PFILE_FS_SECTOR_SIZE_INFORMATION;
+
+#if !defined(Q_CC_CLANG) && !defined(Q_CC_MINGW)
+// keep the following enumeration as is, taken from
+// https://docs.microsoft.com/en-us/windows-hardware/drivers/ddi/wdm/ne-wdm-_fsinfoclass
+// Unfortunately we can't include the wdm.h header, so we duplicate the code here.
+typedef enum _FSINFOCLASS {
+    FileFsVolumeInformation,
+    FileFsLabelInformation,
+    FileFsSizeInformation,
+    FileFsDeviceInformation,
+    FileFsAttributeInformation,
+    FileFsControlInformation,
+    FileFsFullSizeInformation,
+    FileFsObjectIdInformation,
+    FileFsDriverPathInformation,
+    FileFsVolumeFlagsInformation,
+    FileFsSectorSizeInformation,
+    FileFsDataCopyInformation,
+    FileFsMetadataSizeInformation,
+    FileFsFullSizeInformationEx,
+    FileFsMaximumInformation
+} FS_INFORMATION_CLASS, *PFS_INFORMATION_CLASS;
+#endif
+
+QT_END_NAMESPACE
+
+#endif // QNTDLL_P_H
diff --git a/src/corelib/io/qstorageinfo_p.h b/src/corelib/io/qstorageinfo_p.h
index 421e364311..c0f7595c08 100644
--- a/src/corelib/io/qstorageinfo_p.h
+++ b/src/corelib/io/qstorageinfo_p.h
@@ -74,6 +74,8 @@ protected:
 #if defined(Q_OS_WIN)
     void retrieveVolumeInfo();
     void retrieveDiskFreeSpace();
+    bool queryStorageProperty();
+    void queryFileFsSectorSizeInformation();
 #elif defined(Q_OS_MAC)
     void retrievePosixInfo();
     void retrieveUrlProperties(bool initRootPath = false);
diff --git a/src/corelib/io/qstorageinfo_win.cpp b/src/corelib/io/qstorageinfo_win.cpp
index 5a65b78d63..d594551425 100644
--- a/src/corelib/io/qstorageinfo_win.cpp
+++ b/src/corelib/io/qstorageinfo_win.cpp
@@ -41,11 +41,13 @@
 
 #include <QtCore/qdir.h>
 #include <QtCore/qfileinfo.h>
+#include <QtCore/qmutex.h>
 #include <QtCore/qvarlengtharray.h>
 
 #include "qfilesystementry_p.h"
+#include "private/qsystemlibrary_p.h"
 
-#include <qt_windows.h>
+#include "qntdll_p.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -134,6 +136,9 @@ void QStorageInfoPrivate::doStat()
         return;
     device = getDevice(rootPath);
     retrieveDiskFreeSpace();
+
+    if (!queryStorageProperty())
+        queryFileFsSectorSizeInformation();
 }
 
 void QStorageInfoPrivate::retrieveVolumeInfo()
@@ -204,4 +209,139 @@ QStorageInfo QStorageInfoPrivate::root()
     return QStorageInfo(QDir::fromNativeSeparators(QFile::decodeName(qgetenv("SystemDrive"))));
 }
 
+bool QStorageInfoPrivate::queryStorageProperty()
+{
+    QString path = QDir::toNativeSeparators(uR"(\\.\)" + rootPath);
+    if (path.endsWith(u'\\'))
+        path.chop(1);
+
+    HANDLE handle = CreateFile(reinterpret_cast<const wchar_t *>(path.utf16()),
+                               0, // no access to the drive
+                               FILE_SHARE_READ | FILE_SHARE_WRITE,
+                               nullptr,
+                               OPEN_EXISTING,
+                               0,
+                               nullptr);
+    if (handle == INVALID_HANDLE_VALUE)
+        return false;
+
+    STORAGE_PROPERTY_QUERY spq;
+    memset(&spq, 0, sizeof(spq));
+    spq.PropertyId = StorageAccessAlignmentProperty;
+    spq.QueryType = PropertyStandardQuery;
+
+    STORAGE_ACCESS_ALIGNMENT_DESCRIPTOR saad;
+    memset(&saad, 0, sizeof(saad));
+
+    DWORD bytes = 0;
+    BOOL result = DeviceIoControl(handle,
+                                  IOCTL_STORAGE_QUERY_PROPERTY,
+                                  &spq, sizeof(spq),
+                                  &saad, sizeof(saad),
+                                  &bytes,
+                                  nullptr);
+    CloseHandle(handle);
+    if (result)
+        blockSize = saad.BytesPerPhysicalSector;
+    return result;
+}
+
+struct Helper
+{
+    QBasicMutex mutex;
+    QSystemLibrary ntdll {u"ntdll"_qs};
+};
+Q_GLOBAL_STATIC(Helper, gNtdllHelper)
+
+inline QFunctionPointer resolveSymbol(QSystemLibrary *ntdll, const char *name)
+{
+    QFunctionPointer symbolFunctionPointer = ntdll->resolve(name);
+    if (Q_UNLIKELY(!symbolFunctionPointer))
+        qWarning("Failed to resolve the symbol: %s", name);
+    return symbolFunctionPointer;
+}
+
+#define GENERATE_SYMBOL(symbolName, returnType, ...) \
+using Qt##symbolName = returnType (NTAPI *) (__VA_ARGS__); \
+static Qt##symbolName qt##symbolName = nullptr;
+
+#define RESOLVE_SYMBOL(name) \
+    do { \
+        qt##name = reinterpret_cast<Qt##name>(resolveSymbol(ntdll, #name)); \
+        if (!qt##name) \
+            return false; \
+    } while (false)
+
+GENERATE_SYMBOL(RtlInitUnicodeString, void, PUNICODE_STRING, PCWSTR);
+GENERATE_SYMBOL(NtCreateFile, NTSTATUS, PHANDLE, ACCESS_MASK, POBJECT_ATTRIBUTES,
+    PIO_STATUS_BLOCK, PLARGE_INTEGER, ULONG, ULONG, ULONG, ULONG, PVOID, ULONG);
+GENERATE_SYMBOL(NtQueryVolumeInformationFile, NTSTATUS, HANDLE, PIO_STATUS_BLOCK, PVOID, ULONG,
+    FS_INFORMATION_CLASS);
+
+void QStorageInfoPrivate::queryFileFsSectorSizeInformation()
+{
+    static bool symbolsResolved = [](auto ntdllHelper) {
+        QMutexLocker locker(&ntdllHelper->mutex);
+        auto ntdll = &ntdllHelper->ntdll;
+        if (!ntdll->isLoaded()) {
+            if (!ntdll->load()) {
+                qWarning("Unable to load ntdll.dll.");
+                return false;
+            }
+        }
+
+        RESOLVE_SYMBOL(RtlInitUnicodeString);
+        RESOLVE_SYMBOL(NtCreateFile);
+        RESOLVE_SYMBOL(NtQueryVolumeInformationFile);
+
+        return true;
+    }(gNtdllHelper());
+    if (!symbolsResolved)
+        return;
+
+    FILE_FS_SECTOR_SIZE_INFORMATION ffssi;
+    memset(&ffssi, 0, sizeof(ffssi));
+
+    HANDLE handle = nullptr;
+
+    OBJECT_ATTRIBUTES attrs;
+    memset(&attrs, 0, sizeof(attrs));
+
+    IO_STATUS_BLOCK isb;
+    memset(&isb, 0, sizeof(isb));
+
+    QString path = QDir::toNativeSeparators(uR"(\??\\)" + rootPath);
+    if (!path.endsWith(u'\\'))
+        path.append(u'\\');
+
+    UNICODE_STRING name;
+    qtRtlInitUnicodeString(&name, reinterpret_cast<const wchar_t *>(path.utf16()));
+
+    InitializeObjectAttributes(&attrs, &name, 0, nullptr, nullptr);
+
+    NTSTATUS status = qtNtCreateFile(&handle,
+                                     FILE_READ_ATTRIBUTES,
+                                     &attrs,
+                                     &isb,
+                                     nullptr,
+                                     FILE_ATTRIBUTE_NORMAL,
+                                     FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE,
+                                     FILE_OPEN,
+                                     0,
+                                     nullptr,
+                                     0);
+    if (!NT_SUCCESS(status))
+        return;
+
+    memset(&isb, 0, sizeof(isb));
+    status = qtNtQueryVolumeInformationFile(handle,
+                                            &isb,
+                                            &ffssi,
+                                            sizeof(ffssi),
+                                            FS_INFORMATION_CLASS(10)); // FileFsSectorSizeInformation
+    CloseHandle(handle);
+    if (NT_SUCCESS(status))
+        blockSize = ffssi.PhysicalBytesPerSectorForAtomicity;
+}
+
 QT_END_NAMESPACE