diff --git a/src/add-ons/kernel/busses/scsi/ahci/Jamfile b/src/add-ons/kernel/busses/scsi/ahci/Jamfile
index 81a608b61e..5efa4eeb50 100644
--- a/src/add-ons/kernel/busses/scsi/ahci/Jamfile
+++ b/src/add-ons/kernel/busses/scsi/ahci/Jamfile
@@ -2,5 +2,6 @@ SubDir HAIKU_TOP src add-ons kernel busses scsi ahci ;
 
 KernelAddon ahci :
 	ahci.c
+	ahci_controller.cpp
 	ahci_sim.cpp
 	;
diff --git a/src/add-ons/kernel/busses/scsi/ahci/ahci_controller.cpp b/src/add-ons/kernel/busses/scsi/ahci/ahci_controller.cpp
new file mode 100644
index 0000000000..fec9f6293a
--- /dev/null
+++ b/src/add-ons/kernel/busses/scsi/ahci/ahci_controller.cpp
@@ -0,0 +1,73 @@
+/*
+ * Copyright 2007, Marcus Overhagen. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+#include "ahci_controller.h"
+
+#include <KernelExport.h>
+
+#define TRACE(a...) dprintf("\33[34mahci:\33[30m " a)
+#define FLOW(a...)	dprintf("ahci: " a)
+
+
+AHCIController::AHCIController(device_node_handle node, pci_device_module_info *pci, scsi_for_sim_interface * scsi)
+ :	fNode(node)
+ ,	fPCI(pci)
+ ,	fSCSI(scsi)
+ ,	fDevicePresentMask(0)
+{
+
+	fDevicePresentMask = (1 << 7) | (1 << 19);
+}
+
+
+AHCIController::~AHCIController()
+{
+}
+
+
+void
+AHCIController::ExecuteRequest(scsi_ccb *request)
+{
+	if (request->target_lun || !IsDevicePresent(request->target_id)) {
+		request->subsys_status = SCSI_DEV_NOT_THERE;
+		fSCSI->finished(request, 1);
+		return;
+	}
+
+	TRACE("AHCIController::ExecuteRequest opcode %u, length %u\n", request->cdb[0], request->cdb_length);
+
+	request->subsys_status = SCSI_REQ_CMP;
+	fSCSI->finished(request, 1);
+}
+
+
+uchar
+AHCIController::AbortRequest(scsi_ccb *request)
+{
+	if (request->target_lun || !IsDevicePresent(request->target_id))
+		return SCSI_DEV_NOT_THERE;
+
+	return SCSI_REQ_CMP;
+}
+
+
+uchar
+AHCIController::TerminateRequest(scsi_ccb *request)
+{
+	if (request->target_lun || !IsDevicePresent(request->target_id))
+		return SCSI_DEV_NOT_THERE;
+
+	return SCSI_REQ_CMP;
+}
+
+
+uchar
+AHCIController::ResetDevice(uchar targetID, uchar targetLUN)
+{
+	if (targetLUN || !IsDevicePresent(targetID))
+		return SCSI_DEV_NOT_THERE;
+
+	return SCSI_REQ_CMP;
+}
+
diff --git a/src/add-ons/kernel/busses/scsi/ahci/ahci_controller.h b/src/add-ons/kernel/busses/scsi/ahci/ahci_controller.h
new file mode 100644
index 0000000000..4403b197af
--- /dev/null
+++ b/src/add-ons/kernel/busses/scsi/ahci/ahci_controller.h
@@ -0,0 +1,43 @@
+/*
+ * Copyright 2007, Marcus Overhagen. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ */
+#ifndef _AHCI_CONTROLLER_H
+#define _AHCI_CONTROLLER_H
+
+
+#include "ahci_defs.h"
+
+class AHCIController
+{
+public:
+				AHCIController(device_node_handle node, pci_device_module_info *pci, scsi_for_sim_interface * scsi);
+				~AHCIController();
+	
+
+	void		ExecuteRequest(scsi_ccb *request);
+	uchar		AbortRequest(scsi_ccb *request);
+	uchar		TerminateRequest(scsi_ccb *request);
+	uchar		ResetDevice(uchar targetID, uchar targetLUN);
+
+
+private:
+	bool		IsDevicePresent(uint device);
+
+
+private:
+	device_node_handle 			fNode;
+	pci_device_module_info *	fPCI;
+	scsi_for_sim_interface *	fSCSI;
+	uint32						fDevicePresentMask;
+};
+
+
+inline bool
+AHCIController::IsDevicePresent(uint device)
+{
+	return fDevicePresentMask & (1 << device);
+}
+
+
+#endif
diff --git a/src/add-ons/kernel/busses/scsi/ahci/ahci_sim.cpp b/src/add-ons/kernel/busses/scsi/ahci/ahci_sim.cpp
index d707a41b54..790741acce 100644
--- a/src/add-ons/kernel/busses/scsi/ahci/ahci_sim.cpp
+++ b/src/add-ons/kernel/busses/scsi/ahci/ahci_sim.cpp
@@ -3,10 +3,11 @@
  * Distributed under the terms of the MIT License.
  */
 
-#include "ahci_defs.h"
+#include "ahci_controller.h"
 
 #include <KernelExport.h>
 #include <string.h>
+#include <new>
 
 #define TRACE(a...) dprintf("\33[34mahci:\33[30m " a)
 #define FLOW(a...)	dprintf("ahci: " a)
@@ -25,11 +26,7 @@ ahci_scsi_io(scsi_sim_cookie cookie, scsi_ccb *request)
 {
 	TRACE("ahci_scsi_io, cookie %p, path_id %u, target_id %u, target_lun %u\n", 
 		cookie, request->path_id, request->target_id, request->target_lun);
-
-	TRACE("ahci_scsi_io, opcode %u, length %u\n", request->cdb[0], request->cdb_length);
-
-	request->subsys_status = SCSI_REQ_CMP;
-	gSCSI->finished(request, 1);
+	static_cast<AHCIController *>(cookie)->ExecuteRequest(request);
 }
 
 
@@ -38,8 +35,7 @@ static uchar
 ahci_abort_io(scsi_sim_cookie cookie, scsi_ccb *request)
 {
 	TRACE("ahci_abort_io, cookie %p\n", cookie);
-
-	return SCSI_REQ_CMP;
+	return static_cast<AHCIController *>(cookie)->AbortRequest(request);
 }
 
 
@@ -47,8 +43,7 @@ static uchar
 ahci_reset_device(scsi_sim_cookie cookie, uchar targetID, uchar targetLUN)
 {
 	TRACE("ahci_reset_device, cookie %p\n", cookie);
-
-	return SCSI_REQ_CMP;
+	return static_cast<AHCIController *>(cookie)->ResetDevice(targetID, targetLUN);
 }
 
 
@@ -57,8 +52,7 @@ static uchar
 ahci_terminate_io(scsi_sim_cookie cookie, scsi_ccb *request)
 {
 	TRACE("ahci_terminate_io, cookie %p\n", cookie);
-
-	return SCSI_REQ_CMP;
+	return static_cast<AHCIController *>(cookie)->TerminateRequest(request);
 }
 
 
@@ -131,7 +125,10 @@ static status_t
 ahci_sim_init_bus(device_node_handle node, void *user_cookie, void **_cookie)
 {
 	TRACE("ahci_sim_init_bus, user_cookie %p\n", user_cookie);
-	*_cookie = (void *)0x1234;
+//	*_cookie = (void *)0x1234;
+	*_cookie = new(std::nothrow) AHCIController(node, gPCI, gSCSI);
+	if (!*_cookie)
+		return B_NO_MEMORY;
 	TRACE("cookie = %p\n", *_cookie);
 	return B_OK;
 }
@@ -141,6 +138,7 @@ static status_t
 ahci_sim_uninit_bus(void *cookie)
 {
 	TRACE("ahci_sim_uninit_bus, cookie %p\n", cookie);
+	delete static_cast<AHCIController *>(cookie);
 	return B_OK;
 }