dll: FspFileSystemLoop()

2025-06-14 15:52:47 -05:00 · 2015-12-30 17:31:24 -08:00
parent db28be473f
commit 422d4ccc79
4 changed files with 45 additions and 62 deletions
--- a/src/dll/loop.c
+++ b/src/dll/loop.c
@ -0,0 +1,154 @@
+/**
+ * @file dll/loop.c
+ *
+ * @copyright 2015 Bill Zissimopoulos
+ */
+
+#include <dll/library.h>
+
+typedef struct _FSP_DISPATCHER_WORK_ITEM
+{
+    FSP_FILE_SYSTEM *FileSystem;
+    __declspec(align(MEMORY_ALLOCATION_ALIGNMENT)) UINT8 RequestBuf[];
+} FSP_DISPATCHER_WORK_ITEM;
+
+FSP_API NTSTATUS FspFileSystemCreate(PWSTR DevicePath,
+    const FSP_FSCTL_VOLUME_PARAMS *VolumeParams,
+    FSP_FILE_SYSTEM_DISPATCHER *Dispatcher,
+    FSP_FILE_SYSTEM **PFileSystem)
+{
+    NTSTATUS Result;
+    FSP_FILE_SYSTEM *FileSystem;
+
+    *PFileSystem = 0;
+
+    FileSystem = MemAlloc(sizeof *FileSystem);
+    if (0 == FileSystem)
+        return STATUS_INSUFFICIENT_RESOURCES;
+    memset(FileSystem, 0, sizeof *FileSystem);
+
+    Result = FspFsctlCreateVolume(DevicePath, VolumeParams,
+        FileSystem->VolumePath, sizeof FileSystem->VolumePath,
+        &FileSystem->VolumeHandle);
+    if (!NT_SUCCESS(Result))
+    {
+        MemFree(FileSystem);
+        return Result;
+    }
+
+    FileSystem->Dispatcher = 0 != Dispatcher ? Dispatcher : FspFileSystemDirectDispatcher;
+
+    *PFileSystem = FileSystem;
+
+    return STATUS_SUCCESS;
+}
+
+FSP_API VOID FspFileSystemDelete(FSP_FILE_SYSTEM *FileSystem)
+{
+    CloseHandle(FileSystem->VolumeHandle);
+    MemFree(FileSystem);
+}
+
+FSP_API NTSTATUS FspFileSystemLoop(FSP_FILE_SYSTEM *FileSystem)
+{
+    NTSTATUS Result;
+    PUINT8 RequestBuf, RequestBufEnd;
+    SIZE_T RequestBufSize;
+    FSP_FSCTL_TRANSACT_REQ *Request, *NextRequest;
+
+    RequestBuf = MemAlloc(FSP_FSCTL_TRANSACT_REQ_BUFFER_SIZEMIN);
+    if (0 == RequestBuf)
+        return STATUS_INSUFFICIENT_RESOURCES;
+
+    for (;;)
+    {
+        RequestBufSize = FSP_FSCTL_TRANSACT_REQ_BUFFER_SIZEMIN;
+        Result = FspFsctlTransact(FileSystem->VolumeHandle, 0, 0, RequestBuf, &RequestBufSize);
+        if (!NT_SUCCESS(Result))
+            goto exit;
+        RequestBufEnd = RequestBuf + RequestBufSize;
+
+        Request = (PVOID)RequestBuf;
+        for (;;)
+        {
+            NextRequest = FspFsctlTransactConsumeRequest(Request, RequestBufEnd);
+            if (0 == NextRequest)
+                break;
+
+            Result = FileSystem->Dispatcher(FileSystem, Request);
+            if (!NT_SUCCESS(Result))
+                goto exit;
+
+            Request = NextRequest;
+        }
+    }
+
+exit:
+    MemFree(RequestBuf);
+
+    return Result;
+}
+
+FSP_API NTSTATUS FspFileSystemDirectDispatcher(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request)
+{
+    if (FspFsctlTransactKindCount <= Request->Kind || 0 == FileSystem->Operations[Request->Kind])
+        return FspSendResponseWithStatus(FileSystem, Request, STATUS_INVALID_DEVICE_REQUEST);
+
+    FileSystem->Operations[Request->Kind](FileSystem, Request);
+    return STATUS_SUCCESS;
+}
+
+static DWORD WINAPI FspFileSystemPoolDispatcherWorker(PVOID Param)
+{
+    FSP_DISPATCHER_WORK_ITEM *WorkItem = Param;
+    FSP_FSCTL_TRANSACT_REQ *Request = (PVOID)WorkItem->RequestBuf;
+
+    WorkItem->FileSystem->Operations[Request->Kind](WorkItem->FileSystem, Request);
+    MemFree(WorkItem);
+
+    return 0;
+}
+
+FSP_API NTSTATUS FspFileSystemPoolDispatcher(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request)
+{
+    if (FspFsctlTransactKindCount <= Request->Kind || 0 == FileSystem->Operations[Request->Kind])
+        return FspSendResponseWithStatus(FileSystem, Request, STATUS_INVALID_DEVICE_REQUEST);
+
+    FSP_DISPATCHER_WORK_ITEM *WorkItem = MemAlloc(sizeof *WorkItem + Request->Size);
+    if (0 == WorkItem)
+        return STATUS_INSUFFICIENT_RESOURCES;
+
+    WorkItem->FileSystem = FileSystem;
+    memcpy(WorkItem->RequestBuf, Request, Request->Size);
+
+    BOOLEAN Success = QueueUserWorkItem(
+        FspFileSystemPoolDispatcherWorker, WorkItem, WT_EXECUTEDEFAULT);
+    if (!Success)
+    {
+        NTSTATUS Result0 = FspNtStatusFromWin32(GetLastError());
+        MemFree(WorkItem);
+        return Result0;
+    }
+
+    return STATUS_SUCCESS;
+}
+
+FSP_API NTSTATUS FspSendResponse(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_RSP *Response)
+{
+    return FspFsctlTransact(FileSystem->VolumeHandle, Response, Response->Size, 0, 0);
+}
+
+FSP_API NTSTATUS FspSendResponseWithStatus(FSP_FILE_SYSTEM *FileSystem,
+    FSP_FSCTL_TRANSACT_REQ *Request, NTSTATUS Result)
+{
+    FSP_FSCTL_TRANSACT_RSP Response;
+    memset(&Response, 0, sizeof Response);
+    Response.Size = sizeof Response;
+    Response.Kind = Request->Kind;
+    Response.Hint = Request->Hint;
+    Response.IoStatus.Status = Result;
+    return FspSendResponse(FileSystem, &Response);
+}