From aef92bcf23c0dea150e7864a4ef81984325fd6a5 Mon Sep 17 00:00:00 2001
From: Liryna <liryna.stark@gmail.com>
Date: Sun, 18 Feb 2024 08:08:07 -0500
Subject: [PATCH] Kernel/Library - Fix ALLOW_IPC_BATCHING flag unset in kernel

---
 dokan/dokan.c                 | 10 ++++++++--
 samples/dokan_mirror/mirror.c |  4 ++++
 samples/mirror_test.ps1       |  5 +++++
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/dokan/dokan.c b/dokan/dokan.c
index f2363d48..65140911 100644
--- a/dokan/dokan.c
+++ b/dokan/dokan.c
@@ -809,7 +809,10 @@ int DOKANAPI DokanCreateFileSystem(_In_ PDOKAN_OPTIONS DokanOptions,
     DokanOptions->Options |= DOKAN_OPTION_ALLOW_IPC_BATCHING;
     mainPullThreadCount = DOKAN_MAIN_PULL_THREAD_COUNT_MAX;
   }
-  DbgPrintW(L"Dokan: Using %d main pull threads\n", mainPullThreadCount);
+  BOOLEAN allowIpcBatching =
+      (BOOLEAN)(DokanOptions->Options & DOKAN_OPTION_ALLOW_IPC_BATCHING);
+  DbgPrintW(L"Dokan: Using %d main pull threads with ipc batching: %d\n",
+            mainPullThreadCount, allowIpcBatching);
   for (DWORD x = 0; x < mainPullThreadCount; ++x) {
     PDOKAN_IO_EVENT ioEvent = PopIoEventBuffer();
     if (!ioEvent) {
@@ -818,7 +821,7 @@ int DOKANAPI DokanCreateFileSystem(_In_ PDOKAN_OPTIONS DokanOptions,
       return DOKAN_MOUNT_ERROR;
     }
     ioEvent->DokanInstance = dokanInstance;
-    QueueIoEvent(ioEvent, DokanOptions->Options & DOKAN_OPTION_ALLOW_IPC_BATCHING
+    QueueIoEvent(ioEvent, allowIpcBatching
                               ? DispatchBatchIoCallback
                               : DispatchDedicatedIoCallback);
   }
@@ -1109,6 +1112,9 @@ int DokanStart(_In_ PDOKAN_INSTANCE DokanInstance) {
   if (DokanInstance->DokanOptions->Options & DOKAN_OPTION_DISPATCH_DRIVER_LOGS) {
     eventStart.Flags |= DOKAN_EVENT_DISPATCH_DRIVER_LOGS;
   }
+  if (DokanInstance->DokanOptions->Options & DOKAN_OPTION_ALLOW_IPC_BATCHING) {
+    eventStart.Flags |= DOKAN_EVENT_ALLOW_IPC_BATCHING;
+  }
   if (driverLetter && mountManager &&
       !CheckDriveLetterAvailability(DokanInstance->MountPoint[0])) {
     eventStart.Flags |= DOKAN_EVENT_DRIVE_LETTER_IN_USE;
diff --git a/samples/dokan_mirror/mirror.c b/samples/dokan_mirror/mirror.c
index 5e196801..5090b082 100644
--- a/samples/dokan_mirror/mirror.c
+++ b/samples/dokan_mirror/mirror.c
@@ -1508,6 +1508,7 @@ void ShowUsage() {
           "  /r RootDirectory (ex. /r c:\\test)\t\t Directory source to mirror.\n"
           "  /l MountPoint (ex. /l m)\t\t\t Mount point. Can be M:\\ (drive letter) or empty NTFS folder C:\\mount\\dokan .\n"
           "  /t Single thread\t\t\t\t Only use a single thread to process events.\n\t\t\t\t\t\t This is highly not recommended as can easily create a bottleneck.\n"
+          "  /g IPC Batching\t\t\t\t Pull batches of events from the driver instead of a single one and execute them parallelly.\n\t\t\t\t\t\t Only recommended for slow (remote) mirrored device.\n"
           "  /d (enable debug output)\t\t\t Enable debug output to an attached debugger.\n"
           "  /s (use stderr for output)\t\t\t Enable debug output to stderr.\n"
           "  /m (use removable drive)\t\t\t Show device as removable media.\n"
@@ -1607,6 +1608,9 @@ int __cdecl wmain(ULONG argc, PWCHAR argv[]) {
     case L'e':
       dokanOptions.Options |= DOKAN_OPTION_DISPATCH_DRIVER_LOGS;
       break;
+    case L'g':
+      dokanOptions.Options |= DOKAN_OPTION_ALLOW_IPC_BATCHING;
+      break;
     case L'b':
       // Only work when mirroring a folder with setCaseSensitiveInfo option enabled on win10
       dokanOptions.Options |= DOKAN_OPTION_CASE_SENSITIVE;
diff --git a/samples/mirror_test.ps1 b/samples/mirror_test.ps1
index ea13b09a..963fdced 100644
--- a/samples/mirror_test.ps1
+++ b/samples/mirror_test.ps1
@@ -39,6 +39,11 @@ $Configs = @(
 		"Destination" = "$($DokanDriverLetter):";
 		"Name" = "driveRemovable";
 	},
+	@{
+		"MirrorArguments" = "/l $DokanDriverLetter /g";
+		"Destination" = "$($DokanDriverLetter):";
+		"Name" = "ipcBatching";
+	},
 	@{
 		"MirrorArguments" = "/l $DokanDriverLetter /o";
 		"Destination" = "$($DokanDriverLetter):";