diff --git a/inc/winfsp/fsctl.h b/inc/winfsp/fsctl.h
index c3c9d344..714f077c 100644
--- a/inc/winfsp/fsctl.h
+++ b/inc/winfsp/fsctl.h
@@ -24,12 +24,17 @@
 extern "C" {
 #endif
 
+/* static_assert is a C++11 feature, but seems to work with C on MSVC 2015 */
+#if defined(WINFSP_SYS_INTERNAL) || defined(WINFSP_DLL_INTERNAL)
+#define FSP_FSCTL_STATIC_ASSERT(e,m)    static_assert(e,m)
+#else
+#define FSP_FSCTL_STATIC_ASSERT(e,m)
+#endif
+
 #define FSP_FSCTL_DRIVER_NAME           "WinFsp"
 #define FSP_FSCTL_DISK_DEVICE_NAME      "WinFsp.Disk"
 #define FSP_FSCTL_NET_DEVICE_NAME       "WinFsp.Net"
 
-#define FSP_FSCTL_VOLUME_PARAMS_PREFIX  "\\VolumeParams="
-
 // {6F9D25FA-6DEE-4A9D-80F5-E98E14F35E54}
 extern const __declspec(selectany) GUID FspFsctlDeviceClassGuid =
     { 0x6f9d25fa, 0x6dee, 0x4a9d, { 0x80, 0xf5, 0xe9, 0x8e, 0x14, 0xf3, 0x5e, 0x54 } };
@@ -55,9 +60,14 @@ extern const __declspec(selectany) GUID FspFsvrtDeviceClassGuid =
 #define FSP_FSCTL_STOP                  \
     CTL_CODE(FILE_DEVICE_FILE_SYSTEM, 0x800 + 'S', METHOD_BUFFERED, FILE_ANY_ACCESS)
 
+#define FSP_FSCTL_VOLUME_PARAMS_PREFIX  "\\VolumeParams="
+
 #define FSP_FSCTL_VOLUME_NAME_SIZE      (64 * sizeof(WCHAR))
-#define FSP_FSCTL_VOLUME_PREFIX_SIZE    (64 * sizeof(WCHAR))
+#define FSP_FSCTL_VOLUME_PREFIX_SIZE    (192 * sizeof(WCHAR))
+#define FSP_FSCTL_VOLUME_FSNAME_SIZE    (16 * sizeof(WCHAR))
 #define FSP_FSCTL_VOLUME_NAME_SIZEMAX   (FSP_FSCTL_VOLUME_NAME_SIZE + FSP_FSCTL_VOLUME_PREFIX_SIZE)
+FSP_FSCTL_STATIC_ASSERT(FSP_FSCTL_VOLUME_NAME_SIZEMAX <= 260 * sizeof(WCHAR),
+    "Max volume name size is greater than MAX_PATH.");
 
 #define FSP_FSCTL_TRANSACT_PATH_SIZEMAX 2048
 
@@ -135,6 +145,7 @@ typedef struct
     UINT32 ExtendedAttributes:1;        /* unimplemented; set to 0 */
     UINT32 ReadOnlyVolume:1;
     WCHAR Prefix[FSP_FSCTL_VOLUME_PREFIX_SIZE / sizeof(WCHAR)]; /* UNC prefix (\Server\Share) */
+    WCHAR FileSystemName[FSP_FSCTL_VOLUME_FSNAME_SIZE / sizeof(WCHAR)];
 } FSP_FSCTL_VOLUME_PARAMS;
 typedef struct
 {
diff --git a/inc/winfsp/winfsp.h b/inc/winfsp/winfsp.h
index cc677ff6..79da3762 100644
--- a/inc/winfsp/winfsp.h
+++ b/inc/winfsp/winfsp.h
@@ -776,14 +776,8 @@ typedef struct _FSP_FILE_SYSTEM_INTERFACE
      */
     NTSTATUS (*Reserved[41])();
 } FSP_FILE_SYSTEM_INTERFACE;
-#if defined(WINFSP_DLL_INTERNAL)
-/*
- * Static_assert is a C++11 feature, but seems to work with C on MSVC 2015.
- * Use it to verify that FSP_FILE_SYSTEM_INTERFACE has the right size.
- */
-static_assert(sizeof(FSP_FILE_SYSTEM_INTERFACE) == 64 * sizeof(NTSTATUS (*)()),
+FSP_FSCTL_STATIC_ASSERT(sizeof(FSP_FILE_SYSTEM_INTERFACE) == 64 * sizeof(NTSTATUS (*)()),
     "FSP_FILE_SYSTEM_INTERFACE must have 64 entries.");
-#endif
 typedef struct _FSP_FILE_SYSTEM
 {
     UINT16 Version;
diff --git a/src/dll/fsctl.c b/src/dll/fsctl.c
index 2fa10c17..ec54b804 100644
--- a/src/dll/fsctl.c
+++ b/src/dll/fsctl.c
@@ -32,7 +32,7 @@ FSP_API NTSTATUS FspFsctlCreateVolume(PWSTR DevicePath,
     NTSTATUS Result;
     PWSTR DeviceRoot;
     SIZE_T DeviceRootSize, DevicePathSize;
-    WCHAR DevicePathBuf[MAX_PATH], *DevicePathPtr, *DevicePathEnd;
+    WCHAR DevicePathBuf[MAX_PATH + sizeof *VolumeParams], *DevicePathPtr, *DevicePathEnd;
     HANDLE VolumeHandle = INVALID_HANDLE_VALUE;
     DWORD Bytes;
 
@@ -40,7 +40,7 @@ FSP_API NTSTATUS FspFsctlCreateVolume(PWSTR DevicePath,
         VolumeNameBuf[0] = L'\0';
     *PVolumeHandle = INVALID_HANDLE_VALUE;
 
-    /* check lengths; everything (including encoded volume params) must fit within MAX_PATH */
+    /* check lengths; everything (including encoded volume params) must fit within DevicePathBuf */
     DeviceRoot = L'\\' == DevicePath[0] ? GLOBALROOT : GLOBALROOT "\\Device\\";
     DeviceRootSize = lstrlenW(DeviceRoot) * sizeof(WCHAR);
     DevicePathSize = lstrlenW(DevicePath) * sizeof(WCHAR);
diff --git a/tst/memfs/memfs.cpp b/tst/memfs/memfs.cpp
index d79b2a59..d574d822 100644
--- a/tst/memfs/memfs.cpp
+++ b/tst/memfs/memfs.cpp
@@ -1153,6 +1153,7 @@ NTSTATUS MemfsCreate(
     VolumeParams.ReparsePointsAccessCheck = 0;
     if (0 != VolumePrefix)
         wcscpy_s(VolumeParams.Prefix, sizeof VolumeParams.Prefix / sizeof(WCHAR), VolumePrefix);
+    wcscpy_s(VolumeParams.FileSystemName, sizeof VolumeParams.FileSystemName / sizeof(WCHAR), L"MEMFS");
 
     Result = FspFileSystemCreate(DevicePath, &VolumeParams, &MemfsInterface, &Memfs->FileSystem);
     if (!NT_SUCCESS(Result))