From 671c0c12ab7adf593df0bf6d6c5f449a6c1ca2ea Mon Sep 17 00:00:00 2001
From: Bill Zissimopoulos <billziss@navimatics.com>
Date: Thu, 15 Dec 2016 16:15:22 -0800
Subject: [PATCH] sys: FSCTL_QUERY_PERSISTENT_VOLUME_STATE

---
 src/sys/fsctl.c              | 36 ++++++++++++++++++++++++++++++++++++
 tst/winfsp-tests/info-test.c | 24 ++++++++++++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/src/sys/fsctl.c b/src/sys/fsctl.c
index f1a7f5d0..86303ea1 100644
--- a/src/sys/fsctl.c
+++ b/src/sys/fsctl.c
@@ -29,6 +29,8 @@ static NTSTATUS FspFsvolFileSystemControlOplock(
     PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
 static IO_COMPLETION_ROUTINE FspFsvolFileSystemControlOplockCompletion;
 static WORKER_THREAD_ROUTINE FspFsvolFileSystemControlOplockCompletionWork;
+static NTSTATUS FspFsvolFileSystemControlQueryPersistentVolumeState(
+    PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
 static NTSTATUS FspFsvolFileSystemControl(
     PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp);
 FSP_IOCMPL_DISPATCH FspFsvolFileSystemControlComplete;
@@ -42,6 +44,7 @@ FSP_DRIVER_DISPATCH FspFileSystemControl;
 #pragma alloc_text(PAGE, FspFsvolFileSystemControlOplock)
 // !#pragma alloc_text(PAGE, FspFsvolFileSystemControlOplockCompletion)
 #pragma alloc_text(PAGE, FspFsvolFileSystemControlOplockCompletionWork)
+#pragma alloc_text(PAGE, FspFsvolFileSystemControlQueryPersistentVolumeState)
 #pragma alloc_text(PAGE, FspFsvolFileSystemControl)
 #pragma alloc_text(PAGE, FspFsvolFileSystemControlComplete)
 #pragma alloc_text(PAGE, FspFsvolFileSystemControlRequestFini)
@@ -473,6 +476,36 @@ static VOID FspFsvolFileSystemControlOplockCompletionWork(PVOID Context)
     FspFree(CompletionContext);
 }
 
+static NTSTATUS FspFsvolFileSystemControlQueryPersistentVolumeState(
+    PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
+{
+    PAGED_CODE();
+
+    PVOID Buffer = Irp->AssociatedIrp.SystemBuffer;
+    ULONG InputBufferLength = IrpSp->Parameters.FileSystemControl.InputBufferLength;
+    ULONG OutputBufferLength = IrpSp->Parameters.FileSystemControl.OutputBufferLength;
+    PFILE_FS_PERSISTENT_VOLUME_INFORMATION Info;
+
+    if (0 == Buffer)
+        return STATUS_INVALID_PARAMETER;
+
+    if (sizeof(FILE_FS_PERSISTENT_VOLUME_INFORMATION) > InputBufferLength ||
+        sizeof(FILE_FS_PERSISTENT_VOLUME_INFORMATION) > OutputBufferLength)
+        return STATUS_BUFFER_TOO_SMALL;
+
+    Info = Buffer;
+    if (1 != Info->Version ||
+        !FlagOn(Info->FlagMask, PERSISTENT_VOLUME_STATE_SHORT_NAME_CREATION_DISABLED))
+        return STATUS_INVALID_PARAMETER;
+
+    RtlZeroMemory(Info, sizeof(FILE_FS_PERSISTENT_VOLUME_INFORMATION));
+    Info->VolumeFlags = PERSISTENT_VOLUME_STATE_SHORT_NAME_CREATION_DISABLED;
+
+    Irp->IoStatus.Information = sizeof(FILE_FS_PERSISTENT_VOLUME_INFORMATION);
+
+    return STATUS_SUCCESS;
+}
+
 static NTSTATUS FspFsvolFileSystemControl(
     PDEVICE_OBJECT FsvolDeviceObject, PIRP Irp, PIO_STACK_LOCATION IrpSp)
 {
@@ -506,6 +539,9 @@ static NTSTATUS FspFsvolFileSystemControl(
         case FSCTL_REQUEST_OPLOCK:
             Result = FspFsvolFileSystemControlOplock(FsvolDeviceObject, Irp, IrpSp);
             break;
+        case FSCTL_QUERY_PERSISTENT_VOLUME_STATE:
+            Result = FspFsvolFileSystemControlQueryPersistentVolumeState(FsvolDeviceObject, Irp, IrpSp);
+            break;
         }
         break;
     }
diff --git a/tst/winfsp-tests/info-test.c b/tst/winfsp-tests/info-test.c
index dc25ac78..3ee03bd0 100644
--- a/tst/winfsp-tests/info-test.c
+++ b/tst/winfsp-tests/info-test.c
@@ -1039,6 +1039,8 @@ void getvolinfo_dotest(ULONG Flags, PWSTR Prefix, ULONG FileInfoTimeout)
     ULARGE_INTEGER TotalBytes;
     ULARGE_INTEGER FreeBytes;
     HANDLE Handle;
+    FILE_FS_PERSISTENT_VOLUME_INFORMATION PersistentVolumeInfo, PersistentVolumeInfoOut;
+    DWORD BytesTransferred;
 
     StringCbPrintfW(FilePath, sizeof FilePath, L"%s%s\\",
         Prefix ? L"" : L"\\\\?\\GLOBALROOT", Prefix ? Prefix : memfs_volumename(memfs));
@@ -1078,6 +1080,28 @@ void getvolinfo_dotest(ULONG Flags, PWSTR Prefix, ULONG FileInfoTimeout)
     ASSERT(FILE_TYPE_DISK == FileType);
     CloseHandle(Handle);
 
+    StringCbPrintfW(FilePath, sizeof FilePath, L"%s%s%s",
+        -1 == Flags ? L"\\\\.\\" : L"",
+        Prefix ? L"" : L"\\\\?\\GLOBALROOT", Prefix ? Prefix : memfs_volumename(memfs));
+
+    Handle = CreateFileW(FilePath,
+        FILE_READ_DATA, FILE_SHARE_READ | FILE_SHARE_WRITE, 0, OPEN_EXISTING,
+        FILE_FLAG_BACKUP_SEMANTICS, 0);
+    ASSERT(INVALID_HANDLE_VALUE != Handle);
+    memset(&PersistentVolumeInfo, 0, sizeof PersistentVolumeInfo);
+    PersistentVolumeInfo.FlagMask = PERSISTENT_VOLUME_STATE_SHORT_NAME_CREATION_DISABLED;
+    PersistentVolumeInfo.Version = 1;
+    Success = DeviceIoControl(Handle, FSCTL_QUERY_PERSISTENT_VOLUME_STATE,
+        &PersistentVolumeInfo, sizeof PersistentVolumeInfo,
+        &PersistentVolumeInfoOut, sizeof PersistentVolumeInfoOut,
+        &BytesTransferred,
+        0);
+    ASSERT(Success);
+    ASSERT(sizeof PersistentVolumeInfoOut == BytesTransferred);
+    if (-1 != Flags)
+        ASSERT(PERSISTENT_VOLUME_STATE_SHORT_NAME_CREATION_DISABLED == PersistentVolumeInfoOut.VolumeFlags);
+    CloseHandle(Handle);
+
     memfs_stop(memfs);
 }