sys: add trace functionality

build/VStudio/winfsp_sys.vcxproj

@@ -187,6 +187,7 @@
     <ClCompile Include="..\..\src\sys\shutdown.c" />
     <ClCompile Include="..\..\src\sys\silo.c" />
     <ClCompile Include="..\..\src\sys\statistics.c" />
+    <ClCompile Include="..\..\src\sys\trace.c" />
     <ClCompile Include="..\..\src\sys\util.c" />
     <ClCompile Include="..\..\src\sys\volinfo.c" />
     <ClCompile Include="..\..\src\sys\volume.c" />

build/VStudio/winfsp_sys.vcxproj.filters

@@ -125,6 +125,9 @@
     <ClCompile Include="..\..\src\sys\silo.c">
       <Filter>Source</Filter>
     </ClCompile>
+    <ClCompile Include="..\..\src\sys\trace.c">
+      <Filter>Source</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="..\..\src\sys\driver.h">

src/sys/debug.c

@@ -22,6 +22,10 @@
 #include <sys/driver.h>
 
 #if DBG
+
+#undef STATUS_INSUFFICIENT_RESOURCES
+#define STATUS_INSUFFICIENT_RESOURCES   ((NTSTATUS)0xC000009AL)
+
 #define SYM(x)                          case x: return #x;
 #define SYMBRC(x)                       case x: return "[" #x "]";
 
@@ -330,4 +334,5 @@ VOID FspDebugLogIrp(const char *func, PIRP Irp, NTSTATUS Result)
         NtStatusSym(Result),
         (LONGLONG)Irp->IoStatus.Information);
 }
+
 #endif

src/sys/driver.c

@@ -38,6 +38,8 @@ NTSTATUS DriverEntry(
 {
     FSP_ENTER_DRV();
 
+    FSP_TRACE_INIT();
+
     /* setup the driver object */
     DriverObject->MajorFunction[IRP_MJ_CREATE] = FspCreate;
     DriverObject->MajorFunction[IRP_MJ_CLOSE] = FspClose;
@@ -157,6 +159,8 @@ exit:
             FspSiloFinalize();
         if (InitDoneGRes)
             ExDeleteResourceLite(&FspDeviceGlobalResource);
+
+        FSP_TRACE_FINI();
     }
 
 #pragma prefast(suppress:28175, "We are in DriverEntry: ok to access DriverName")

src/sys/driver.h

@@ -147,6 +147,40 @@ VOID FspDebugLogIrp(const char *func, PIRP Irp, NTSTATUS Result);
 #define DEBUGTEST_EX(C, Percent, Deflt) (Deflt)
 #endif
 
+/* trace */
+#if FSP_TRACE_ENABLED
+VOID FspTraceInitialize(VOID);
+VOID FspTraceFinalize(VOID);
+VOID FspTrace(const char *file, int line, const char *func);
+VOID FspTraceNtStatus(const char *file, int line, const char *func, NTSTATUS Status);
+#define FSP_TRACE_INIT()                \
+    (FspTraceInitialize(), FSP_TRACE())
+#define FSP_TRACE_FINI()                \
+    (FSP_TRACE(), FspTraceFinalize())
+#define FSP_TRACE()                     \
+    FspTrace(                           \
+        __FILE__,                       \
+        __LINE__,                       \
+        __FUNCTION__)
+#define FSP_TRACE_NTSTATUS(Status)      \
+    FspTraceNtStatus(                   \
+        __FILE__,                       \
+        __LINE__,                       \
+        __FUNCTION__,                   \
+        Status)
+#else
+#define FSP_TRACE_INIT()                \
+    ((VOID)0)
+#define FSP_TRACE_FINI()                \
+    ((VOID)0)
+#define FSP_TRACE()                     \
+    ((VOID)0)
+#define FSP_TRACE_NTSTATUS(Result)      \
+    ((VOID)0)
+#endif
+#undef STATUS_INSUFFICIENT_RESOURCES
+#define STATUS_INSUFFICIENT_RESOURCES   (FSP_TRACE_NTSTATUS(0xC000009AL), (NTSTATUS)0xC000009AL)
+
 /* FSP_ENTER/FSP_LEAVE */
 #if DBG
 #define FSP_DEBUGLOG_(fmt, rfmt, ...)   \

src/sys/trace.c

@@ -0,0 +1,142 @@
+/**
+ * @file sys/trace.c
+ *
+ * @copyright 2015-2020 Bill Zissimopoulos
+ */
+/*
+ * This file is part of WinFsp.
+ *
+ * You can redistribute it and/or modify it under the terms of the GNU
+ * General Public License version 3 as published by the Free Software
+ * Foundation.
+ *
+ * Licensees holding a valid commercial license may use this software
+ * in accordance with the commercial license agreement provided in
+ * conjunction with the software.  The terms and conditions of any such
+ * commercial license agreement shall govern, supersede, and render
+ * ineffective any application of the GPLv3 license to this software,
+ * notwithstanding of any reference thereto in the software or
+ * associated repository.
+ */
+
+#include <sys/driver.h>
+
+#if FSP_TRACE_ENABLED
+
+#undef STATUS_INSUFFICIENT_RESOURCES
+#define STATUS_INSUFFICIENT_RESOURCES   ((NTSTATUS)0xC000009AL)
+
+static struct
+{
+    HANDLE Handle;
+    PKEVENT Event;
+} FspLowMemoryCondition, FspLowNonPagedPoolCondition, FspLowPagedPoolCondition;
+
+VOID FspTrace(const char *file, int line, const char *func)
+{
+    for (const char *p = file; '\0' != *p; p++)
+        if ('\\' == *p)
+            file = p + 1;
+
+    ASSERT(DISPATCH_LEVEL >= KeGetCurrentIrql());
+    DbgPrintEx(DPFLTR_DEFAULT_ID, DPFLTR_TRACE_LEVEL,
+        DRIVER_NAME ": %s[%s:%d]\n", func, file, line);
+}
+
+VOID FspTraceNtStatus(const char *file, int line, const char *func, NTSTATUS Status)
+{
+    for (const char *p = file; '\0' != *p; p++)
+        if ('\\' == *p)
+            file = p + 1;
+
+    ASSERT(DISPATCH_LEVEL >= KeGetCurrentIrql());
+    BOOLEAN LowMemoryCondition, LowNonPagedPoolCondition, LowPagedPoolCondition;
+    switch (Status)
+    {
+    case STATUS_INSUFFICIENT_RESOURCES:
+        LowMemoryCondition = 0 != FspLowMemoryCondition.Event &&
+            !!KeReadStateEvent(FspLowMemoryCondition.Event);
+        LowNonPagedPoolCondition = 0 != FspLowNonPagedPoolCondition.Event &&
+            !!KeReadStateEvent(FspLowNonPagedPoolCondition.Event);
+        LowPagedPoolCondition = 0 != FspLowPagedPoolCondition.Event &&
+            !!KeReadStateEvent(FspLowPagedPoolCondition.Event);
+        DbgPrintEx(DPFLTR_DEFAULT_ID, DPFLTR_TRACE_LEVEL,
+            DRIVER_NAME ": %s[%s:%d]: STATUS_INSUFFICIENT_RESOURCE (Memory=%c%c%c)\n",
+            func, file, line,
+            LowMemoryCondition ? 'M' : '-',
+            LowNonPagedPoolCondition ? 'N' : '-',
+            LowPagedPoolCondition ? 'P' : '-');
+        break;
+    default:
+        DbgPrintEx(DPFLTR_DEFAULT_ID, DPFLTR_TRACE_LEVEL,
+            DRIVER_NAME ": %s[%s:%d]: Status=%lx\n",
+            func, file, line,
+            Status);
+        break;
+    }
+}
+
+static PKEVENT FspOpenEvent(PWSTR Name, PHANDLE PHandle)
+{
+    UNICODE_STRING ObjectName;
+    OBJECT_ATTRIBUTES ObjectAttributes;
+    HANDLE Handle;
+    PKEVENT Event;
+    NTSTATUS Result;
+
+    *PHandle = 0;
+
+    RtlInitUnicodeString(&ObjectName, Name);
+    InitializeObjectAttributes(&ObjectAttributes,
+        &ObjectName, OBJ_KERNEL_HANDLE, 0, 0);
+    Result = ZwOpenEvent(&Handle,
+        EVENT_ALL_ACCESS, &ObjectAttributes);
+    if (!NT_SUCCESS(Result))
+        return 0;
+
+    Result = ObReferenceObjectByHandle(Handle,
+        0, *ExEventObjectType, KernelMode, &Event, 0);
+    if (!NT_SUCCESS(Result))
+    {
+        ZwClose(Handle);
+        return 0;
+    }
+
+    *PHandle = Handle;
+
+    return Event;
+}
+
+static VOID FspCloseEvent(PKEVENT Event, HANDLE Handle)
+{
+    if (0 != Event)
+        ObDereferenceObject(Event);
+
+    if (0 != Handle)
+        ZwClose(Handle);
+}
+
+VOID FspTraceInitialize(VOID)
+{
+#define OPEN_EVENT(NAME)                \
+    (Fsp ## NAME.Event = FspOpenEvent(L"\\KernelObjects\\" #NAME, &Fsp ## NAME.Handle))
+
+    OPEN_EVENT(LowMemoryCondition);
+    OPEN_EVENT(LowNonPagedPoolCondition);
+    OPEN_EVENT(LowPagedPoolCondition);
+
+#undef OPEN_EVENT
+}
+
+VOID FspTraceFinalize(VOID)
+{
+#define CLOSE_EVENT(NAME)               \
+    (FspCloseEvent(Fsp ## NAME.Event, Fsp ## NAME.Handle), Fsp ## NAME.Event = 0, Fsp ## NAME.Handle = 0)
+
+    CLOSE_EVENT(LowMemoryCondition);
+    CLOSE_EVENT(LowNonPagedPoolCondition);
+    CLOSE_EVENT(LowPagedPoolCondition);
+
+#undef CLOSE_EVENT
+}
+#endif