sel4: add signal support

Fixes #1716
Issue #2044

repos/base-sel4/lib/mk/core.mk

@@ -59,7 +59,6 @@ vpath io_mem_session_component.cc $(GEN_CORE_DIR)
 vpath io_mem_session_support.cc   $(GEN_CORE_DIR)
 vpath io_port_session_component.cc $(GEN_CORE_DIR)/spec/x86
 vpath platform_services.cc        $(GEN_CORE_DIR)/spec/x86
-vpath signal_source_component.cc  $(GEN_CORE_DIR)
 vpath trace_session_component.cc  $(GEN_CORE_DIR)
 vpath dataspace_component.cc      $(GEN_CORE_DIR)
 vpath core_mem_alloc.cc           $(GEN_CORE_DIR)
@@ -67,4 +66,3 @@ vpath core_rpc_cap_alloc.cc       $(GEN_CORE_DIR)
 vpath dump_alloc.cc               $(GEN_CORE_DIR)
 vpath pager_ep.cc                 $(GEN_CORE_DIR)
 vpath %.cc                        $(REP_DIR)/src/core
-

repos/base-sel4/src/core/capability_space.cc

@@ -192,3 +192,16 @@ Native_capability Capability_space::import(Ipc_cap_data ipc_cap_data)
 
 	return Native_capability(data);
 }
+
+
+Native_capability
+Capability_space::create_notification_cap(Cap_sel &notify_cap)
+{
+	Pd_session const *pd_session = nullptr;
+
+	Native_capability::Data &data =
+		local_capability_space().create_capability(notify_cap, pd_session,
+		                                           Rpc_obj_key());
+
+	return Native_capability(data);
+}

repos/base-sel4/src/core/include/kernel_object.h

@@ -48,6 +48,13 @@ namespace Genode {
 	};
 
 
+	struct Notification_kobj
+	{
+		enum { SEL4_TYPE = seL4_NotificationObject, SIZE_LOG2 = 4 };
+		static char const *name() { return "notification"; }
+	};
+
+
 	struct Cnode_kobj
 	{
 		enum { SEL4_TYPE = seL4_CapTableObject, SIZE_LOG2 = 4 };

repos/base-sel4/src/core/signal_source_component.cc

@@ -0,0 +1,94 @@
+/*
+ * \brief  Implementation of the SIGNAL interface
+ * \author Alexander Boettcher
+ * \date   2016-07-09
+ */
+
+/*
+ * Copyright (C) 2016 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+/* Genode includes */
+#include <base/log.h>
+
+/* core includes */
+#include <platform.h>
+#include <signal_source_component.h>
+
+/* base-internal include */
+#include <core_capability_space.h>
+
+
+using namespace Genode;
+
+
+/*****************************
+ ** Signal-source component **
+ *****************************/
+
+void Signal_source_component::release(Signal_context_component *context)
+{
+	if (context && context->enqueued())
+		_signal_queue.remove(context);
+}
+
+
+void Signal_source_component::submit(Signal_context_component *context,
+                                     unsigned long             cnt)
+{
+	/*
+	 * If the client does not block in 'wait_for_signal', the
+	 * signal will be delivered as result of the next
+	 * 'wait_for_signal' call.
+	 */
+	context->increment_signal_cnt(cnt);
+
+	if (context->enqueued())
+		return;
+
+	_signal_queue.enqueue(context);
+
+	seL4_Signal(Capability_space::ipc_cap_data(_notify).sel.value());
+}
+
+
+Signal_source::Signal Signal_source_component::wait_for_signal()
+{
+	if (_signal_queue.empty())
+		return Signal(0, 0);  /* just a dummy */
+
+	/* dequeue and return pending signal */
+	Signal_context_component *context = _signal_queue.dequeue();
+	Signal result(context->imprint(), context->cnt());
+	context->reset_signal_cnt();
+	return result;
+}
+
+
+Signal_source_component::Signal_source_component(Rpc_entrypoint *ep)
+:
+	_entrypoint(ep), _finalizer(*this),
+	_finalizer_cap(_entrypoint->manage(&_finalizer))
+{
+	Platform &platform = *platform_specific();
+	Range_allocator &phys_alloc = *platform.ram_alloc();
+
+	/* allocate notification object within core's CNode */
+	Cap_sel ny_sel = platform.core_sel_alloc().alloc();
+	create<Notification_kobj>(phys_alloc, platform.core_cnode().sel(), ny_sel);
+
+	_notify = Capability_space::create_notification_cap(ny_sel);
+}
+
+
+Signal_source_component::~Signal_source_component()
+{
+	_finalizer_cap.call<Finalizer::Rpc_exit>();
+	_entrypoint->dissolve(&_finalizer);
+}
+
+
+void Signal_source_component::Finalizer_component::exit() { }

repos/base-sel4/src/include/signal_source/client.h

@@ -0,0 +1,79 @@
+/*
+ * \brief  seL4-specific signal-source client interface
+ * \author Alexander Boettcher
+ * \date   2016-07-09
+ */
+
+/*
+ * Copyright (C) 2016 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INCLUDE__SIGNAL_SOURCE__CLIENT_H_
+#define _INCLUDE__SIGNAL_SOURCE__CLIENT_H_
+
+#include <base/rpc_client.h>
+#include <signal_source/sel4_signal_source.h>
+
+#include <base/internal/capability_space_sel4.h>
+
+#include <base/log.h>
+namespace Genode {
+	class Signal_source_client;
+}
+
+class Genode::Signal_source_client : public Rpc_client<SeL4_signal_source>
+{
+	private:
+
+		Native_capability _notify;
+
+		/**
+		 * Request notification object from signal-source server
+		 */
+		void _init_notify()
+		{
+			_notify = call<Rpc_request_notify_obj>();
+		}
+
+	public:
+
+		/**
+		 * Constructor
+		 */
+		Signal_source_client(Capability<Signal_source> cap)
+		: Rpc_client<SeL4_signal_source>(static_cap_cast<SeL4_signal_source>(cap))
+		{ _init_notify(); }
+
+
+		/*****************************
+		 ** Signal source interface **
+		 *****************************/
+
+		Signal wait_for_signal() override
+		{
+			unsigned const dst_sel = Capability_space::ipc_cap_data(_notify).sel.value();
+
+			Signal signal;
+			do {
+				/*
+				 * Ask ever for a new signal. The seL4 asynchronous mechanism
+				 * squashes multiple notifications into one, so that we may
+				 * miss to ask for a pending signal.
+				 */
+				signal = call<Rpc_wait_for_signal>();
+
+				if (!signal.imprint()) {
+					/* block on notification until signal context was submitted */
+					seL4_CPtr src = dst_sel;
+					seL4_Wait(src, nullptr);
+				}
+			} while (!signal.imprint());
+
+			return signal;
+		}
+};
+
+#endif /* _INCLUDE__SIGNAL_SOURCE__CLIENT_H_ */

repos/base-sel4/src/include/signal_source/rpc_object.h

@@ -0,0 +1,37 @@
+/*
+ * \brief  Signal-source server interface
+ * \author Alexander Boettcher
+ * \date   2016-07-09
+ */
+
+/*
+ * Copyright (C) 2016 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INCLUDE__SIGNAL_SOURCE__RPC_OBJECT_H_
+#define _INCLUDE__SIGNAL_SOURCE__RPC_OBJECT_H_
+
+#include <base/rpc_server.h>
+#include <signal_source/sel4_signal_source.h>
+
+namespace Genode { struct Signal_source_rpc_object; }
+
+
+struct Genode::Signal_source_rpc_object : Rpc_object<SeL4_signal_source,
+                                                     Signal_source_rpc_object>
+{
+	protected:
+
+		Native_capability _notify;
+
+	public:
+
+		Signal_source_rpc_object() {}
+
+		Native_capability _request_notify() { return _notify; }
+};
+
+#endif /* _INCLUDE__SIGNAL_SOURCE__RPC_OBJECT_H_ */

repos/base-sel4/src/include/signal_source/sel4_signal_source.h

@@ -0,0 +1,29 @@
+/*
+ * \brief  seL4-specific signal source RPC interface
+ * \author Alexander Boettcher
+ * \date   2016-07-09
+ */
+
+/*
+ * Copyright (C) 2016 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _INCLUDE__SIGNAL_SOURCE__SEL4_SIGNAL_SOURCE_H_
+#define _INCLUDE__SIGNAL_SOURCE__SEL4_SIGNAL_SOURCE_H_
+
+#include <signal_source/signal_source.h>
+#include <base/rpc_server.h>
+
+namespace Genode { struct SeL4_signal_source; }
+
+
+struct Genode::SeL4_signal_source : Signal_source
+{
+	GENODE_RPC(Rpc_request_notify_obj, Native_capability, _request_notify);
+	GENODE_RPC_INTERFACE_INHERIT(Signal_source, Rpc_request_notify_obj);
+};
+
+#endif /* _INCLUDE__SIGNAL_SOURCE__SEL4_SIGNAL_SOURCE_H_ */

repos/base/src/core/include/core_capability_space.h

@@ -17,7 +17,7 @@
 /* base-internal includes */
 #include <base/internal/rpc_obj_key.h>
 
-namespace Genode { class Pd_session; }
+namespace Genode { class Cap_sel; class Pd_session; }
 
 
 namespace Genode { namespace Capability_space {
@@ -28,6 +28,8 @@ namespace Genode { namespace Capability_space {
 	Native_capability create_rpc_obj_cap(Native_capability ep_cap,
 	                                     Pd_session const *,
 	                                     Rpc_obj_key);
+
+	Native_capability create_notification_cap(Genode::Cap_sel &notify_cap);
 } }
 
 #endif /* _CORE__INCLUDE__CORE_CAPABILITY_SPACE_H_ */