Move server API concept to base framework

This commit introduces the new `Component` interface in the form of the
headers base/component.h and base/entrypoint.h. The os/server.h API
has become merely a compatibilty wrapper and will eventually be removed.
The same holds true for os/signal_rpc_dispatcher.h. The mechanism has
moved to base/signal.h and is now called 'Signal_handler'.

This patch has been tested on base-linux, base-okl4, base-hw, base-nova,
and base-sel4.

Since the patch shuffles headers around, please do a 'make clean' in the
build directory.

Note that this patch changes the default behavior of components. Each
component opens a CAP and SIGNAL session during startup in order to
create the component's 'Entrypoint'. So we have to make sure to adjust
the session routing policies correspondingly. I did this for the
printf.run script but other run scripts may be affected as well.

Issue genodelabs#1832

repos/base-fiasco/lib/mk/base-common.mk

@@ -22,6 +22,7 @@ SRC_CC += server/server.cc server/common.cc
 SRC_CC += thread/thread.cc thread/thread_bootstrap.cc thread/trace.cc
 SRC_CC += thread/myself.cc
 SRC_CC += thread/context_allocator.cc
+SRC_CC += entrypoint/entrypoint.cc
 
 INC_DIR +=  $(REP_DIR)/src/base/lock
 INC_DIR += $(BASE_DIR)/src/base/thread

repos/base-foc/lib/mk/base-common.mk

@@ -22,6 +22,7 @@ SRC_CC += server/server.cc server/common.cc
 SRC_CC += thread/thread.cc thread/thread_bootstrap.cc thread/trace.cc
 SRC_CC += thread/myself.cc
 SRC_CC += thread/context_allocator.cc
+SRC_CC += entrypoint/entrypoint.cc
 
 INC_DIR +=  $(REP_DIR)/src/base/lock
 INC_DIR += $(BASE_DIR)/src/base/lock

repos/base-hw/lib/mk/base-common.inc

@@ -29,6 +29,7 @@ SRC_CC += thread/bootstrap.cc
 SRC_CC += thread/trace.cc
 SRC_CC += thread/context_allocator.cc
 SRC_CC += kernel/interface.cc
+SRC_CC += entrypoint/entrypoint.cc
 
 # add include paths
 INC_DIR +=  $(REP_DIR)/src/base/lock

repos/base-hw/src/base/env.cc

@@ -16,6 +16,7 @@
 #include <base/env.h>
 #include <base/native_env.h>
 
+
 void Genode::upgrade_pd_session_quota(Genode::size_t quota)
 {
 	char buf[128];

repos/base-hw/src/base/signal/signal.cc

@@ -21,12 +21,24 @@
 
 using namespace Genode;
 
+
+namespace Genode {
+
+	/*
+	 * On base-hw, no signal thread is needed.
+	 */
+	void init_signal_thread() __attribute__((weak));
+	void init_signal_thread() { }
+}
+
+
 /********************
  ** Signal context **
  ********************/
 
 void Signal_context::submit(unsigned) { PERR("not implemented"); }
 
+
 /************************
  ** Signal transmitter **
  ************************/
@@ -48,10 +60,9 @@ Signal_receiver::Signal_receiver()
 {
 	/* create a kernel object that corresponds to the receiver */
 	bool session_upgraded = 0;
-	Signal_connection * const s = signal_connection();
 	while (1) {
 		try {
-			_cap = s->alloc_receiver();
+			_cap = env()->signal_session()->alloc_receiver();
 			return;
 		} catch (Signal_session::Out_of_metadata)
 		{
@@ -62,7 +73,7 @@ Signal_receiver::Signal_receiver()
 				return;
 			}
 			PINF("upgrading quota donation for SIGNAL session");
-			env()->parent()->upgrade(s->cap(), "ram_quota=8K");
+			env()->parent()->upgrade(env()->signal_session_cap(), "ram_quota=8K");
 			session_upgraded = 1;
 		}
 	}
@@ -72,7 +83,7 @@ Signal_receiver::Signal_receiver()
 void Signal_receiver::_platform_destructor()
 {
 	/* release server resources of receiver */
-	signal_connection()->free_receiver(_cap);
+	env()->signal_session()->free_receiver(_cap);
 }
 
 
@@ -93,10 +104,9 @@ Signal_context_capability Signal_receiver::manage(Signal_context * const c)
 
 	/* create a context kernel-object at the receiver kernel-object */
 	bool session_upgraded = 0;
-	Signal_connection * const s = signal_connection();
 	while (1) {
 		try {
-			c->_cap = s->alloc_context(_cap, (unsigned long)c);
+			c->_cap = env()->signal_session()->alloc_context(_cap, (unsigned long)c);
 			c->_receiver = this;
 			_contexts.insert(&c->_receiver_le);
 			return c->_cap;
@@ -108,7 +118,7 @@ Signal_context_capability Signal_receiver::manage(Signal_context * const c)
 				return Signal_context_capability();
 			}
 			PINF("upgrading quota donation for signal session");
-			env()->parent()->upgrade(s->cap(), "ram_quota=8K");
+			env()->parent()->upgrade(env()->signal_session_cap(), "ram_quota=8K");
 			session_upgraded = 1;
 		}
 	}

repos/base-hw/src/base/thread/start.cc

@@ -20,7 +20,7 @@
 
 using namespace Genode;
 
-namespace Genode { Rm_session * env_context_area_rm_session(); }
+namespace Genode { extern Rm_session * const env_context_area_rm_session; }
 
 namespace Hw {
 	extern Ram_dataspace_capability _main_thread_utcb_ds;
@@ -47,7 +47,7 @@ void Thread_base::_init_platform_thread(size_t weight, Type type)
 	size_t const utcb_size = sizeof(Native_utcb);
 	addr_t const context_area = Native_config::context_area_virtual_base();
 	addr_t const utcb_new = (addr_t)&_context->utcb - context_area;
-	Rm_session * const rm = env_context_area_rm_session();
+	Rm_session * const rm = env_context_area_rm_session;
 	if (type == REINITIALIZED_MAIN) { rm->detach(utcb_new); }
 
 	/* remap initial main-thread UTCB according to context-area spec */
@@ -74,7 +74,7 @@ void Thread_base::_deinit_platform_thread()
 	addr_t utcb = Context_allocator::addr_to_base(_context) +
 	              Native_config::context_virtual_size() - size -
 	              Native_config::context_area_virtual_base();
-	env_context_area_rm_session()->detach(utcb);
+	env_context_area_rm_session->detach(utcb);
 
 	if (_pager_cap.valid()) {
 		env()->rm_session()->remove_client(_pager_cap);
@@ -98,7 +98,7 @@ void Thread_base::start()
 		addr_t dst = Context_allocator::addr_to_base(_context) +
 		             Native_config::context_virtual_size() - size -
 		             Native_config::context_area_virtual_base();
-		env_context_area_rm_session()->attach_at(ds, dst, size);
+		env_context_area_rm_session->attach_at(ds, dst, size);
 	} catch (...) {
 		PERR("failed to attach userland thread-context");
 		sleep_forever();

repos/base-hw/src/core/include/signal_root.h

@@ -28,7 +28,7 @@ namespace Genode
 	/**
 	 * Provide EP to signal root before it initialises root component
 	 */
-	class Signal_handler
+	class Signal_handler_ep
 	{
 		enum { STACK_SIZE = 4096 };
 
@@ -39,7 +39,7 @@ namespace Genode
 			/**
 			 * Constructor
 			 */
-			Signal_handler(Cap_session * const c)
+			Signal_handler_ep(Cap_session * const c)
 			: _entrypoint(c, STACK_SIZE, "signal") { }
 
 			/***************
@@ -52,7 +52,7 @@ namespace Genode
 	/**
 	 * Provides signal service by managing appropriate sessions to the clients
 	 */
-	class Signal_root : private Signal_handler,
+	class Signal_root : private Signal_handler_ep,
 	                    public  Root_component<Signal_session_component>
 	{
 		public:
@@ -64,7 +64,7 @@ namespace Genode
 			 * \param c   CAP session to be used by the root entrypoint
 			 */
 			Signal_root(Allocator * const md, Cap_session * const c) :
-				Signal_handler(c),
+				Signal_handler_ep(c),
 				Root_component<Signal_session_component>(entrypoint(), md)
 			{ }
 
@@ -79,7 +79,7 @@ namespace Genode
 				size_t ram_quota =
 					Arg_string::find_arg(args, "ram_quota").ulong_value(0);
 				return new (md_alloc())
-					Signal_session_component(md_alloc(), ram_quota);
+					Signal_session_component(nullptr, nullptr, md_alloc(), ram_quota);
 			}
 
 			void _upgrade_session(Signal_session_component *s,

repos/base-hw/src/core/include/signal_session_component.h

@@ -96,8 +96,8 @@ class Genode::Signal_session_component : public Rpc_object<Signal_session>
 		 * \param allocator  RAM allocator for meta data
 		 * \param quota      amount of RAM quota donated to this session
 		 */
-		Signal_session_component(Allocator * const allocator,
-		                         size_t const quota);
+		Signal_session_component(Rpc_entrypoint *, Rpc_entrypoint *,
+		                         Allocator *allocator, size_t const quota);
 
 		~Signal_session_component();
 

repos/base-hw/src/core/signal_session_component.cc

@@ -110,7 +110,9 @@ void Signal_session_component::free_context(Signal_context_capability cap)
 }
 
 
-Signal_session_component::Signal_session_component(Allocator * const allocator,
+Signal_session_component::Signal_session_component(Rpc_entrypoint *,
+                                                   Rpc_entrypoint *,
+                                                   Allocator * const allocator,
                                                    size_t const quota)
 : _allocator(allocator, quota), _receivers_slab(&_allocator),
   _contexts_slab(&_allocator) { }

repos/base-linux/lib/mk/base-common.mk

@@ -21,6 +21,7 @@ SRC_CC += signal/signal.cc signal/common.cc signal/platform.cc
 SRC_CC += server/server.cc server/common.cc
 SRC_CC += thread/trace.cc thread/thread_env.cc thread/context_allocator.cc
 SRC_CC += irq/platform.cc
+SRC_CC += entrypoint/entrypoint.cc
 
 INC_DIR +=  $(REP_DIR)/src/base/lock $(BASE_DIR)/src/base/lock
 INC_DIR +=  $(REP_DIR)/src/base/ipc

repos/base-linux/src/base/env/platform_env.cc

@@ -75,8 +75,7 @@ Platform_env::Local_parent::session(Service_name const &service_name,
 		if (size != ~0UL)
 			size = align_addr(size, get_page_size_log2());
 
-		Rm_session_mmap *rm = new (env()->heap())
-		                      Rm_session_mmap(true, size);
+		Rm_session_mmap *rm = new (_alloc) Rm_session_mmap(true, size);
 
 		return Local_capability<Session>::local_cap(rm);
 	}
@@ -105,8 +104,10 @@ void Platform_env::Local_parent::close(Session_capability session)
 
 
 Platform_env::Local_parent::Local_parent(Parent_capability parent_cap,
-                                         Emergency_ram_reserve &reserve)
-: Expanding_parent_client(parent_cap, reserve)
+                                         Emergency_ram_reserve &reserve,
+                                         Allocator &alloc)
+:
+	Expanding_parent_client(parent_cap, reserve), _alloc(alloc)
 { }
 
 
@@ -149,7 +150,7 @@ static Parent_capability obtain_parent_cap()
 
 Platform_env::Local_parent &Platform_env::_parent()
 {
-	static Local_parent local_parent(obtain_parent_cap(), *this);
+	static Local_parent local_parent(obtain_parent_cap(), *this, _heap);
 	return local_parent;
 }
 
@@ -159,9 +160,22 @@ Platform_env::Platform_env()
 	Platform_env_base(static_cap_cast<Ram_session>(_parent().session("Env::ram_session", "")),
 	                  static_cap_cast<Cpu_session>(_parent().session("Env::cpu_session", "")),
 	                  static_cap_cast<Pd_session> (_parent().session("Env::pd_session",  ""))),
+
+	_cap_session_cap(static_cap_cast<Cap_session>
+		(_parent().session(Cap_session::service_name(), "ram_quota=4K"))),
+
+	_signal_session_cap(static_cap_cast<Signal_session>
+		(_parent().session(Signal_session::service_name(), "ram_quota=16K"))),
+
 	_heap(Platform_env_base::ram_session(), Platform_env_base::rm_session()),
+
+	_context_area(*parent(), *rm_session()),
+
 	_emergency_ram_ds(ram_session()->alloc(_emergency_ram_size()))
 {
+	env_context_area_ram_session = ram_session();
+	env_context_area_rm_session  = &_context_area;
+
 	/* register TID and PID of the main thread at core */
 	cpu_session()->thread_id(parent()->main_thread_cap(),
 	                         lx_getpid(), lx_gettid());

repos/base-linux/src/base/env/platform_env.h

@@ -26,6 +26,8 @@
 #include <base/local_capability.h>
 #include <base/heap.h>
 #include <linux_cpu_session/client.h>
+#include <cap_session/connection.h>
+#include <signal_session/connection.h>
 
 /* local includes (from 'base/src/base/env/') */
 #include <platform_env_common.h>
@@ -314,10 +316,6 @@ namespace Genode {
 
 		private:
 
-			/*******************************
-			 ** Platform-specific members **
-			 *******************************/
-
 			Ram_session_capability       _ram_session_cap;
 			Expanding_ram_session_client _ram_session_client;
 			Cpu_session_capability       _cpu_session_cap;
@@ -347,19 +345,19 @@ namespace Genode {
 			 ** Env interface **
 			 *******************/
 
-			Ram_session            *ram_session()     { return &_ram_session_client; }
-			Ram_session_capability  ram_session_cap() { return  _ram_session_cap; }
-			Rm_session             *rm_session()      { return &_rm_session_mmap; }
-			Linux_cpu_session      *cpu_session()     { return &_cpu_session_client; }
-			Cpu_session_capability  cpu_session_cap() { return  _cpu_session_cap; }
-			Pd_session             *pd_session()      { return &_pd_session_client; }
+			Ram_session            *ram_session()     override { return &_ram_session_client; }
+			Ram_session_capability  ram_session_cap() override { return  _ram_session_cap; }
+			Rm_session             *rm_session()      override { return &_rm_session_mmap; }
+			Linux_cpu_session      *cpu_session()     override { return &_cpu_session_client; }
+			Cpu_session_capability  cpu_session_cap() override { return  _cpu_session_cap; }
+			Pd_session             *pd_session()      override { return &_pd_session_client; }
 
 			/*
 			 * Support functions for implementing fork on Noux.
 			 *
 			 * Not supported on Linux.
 			 */
-			void reinit(Native_capability::Dst, long) { };
+			void reinit(Native_capability::Dst, long) override { };
 			void reinit_main_thread(Rm_session_capability &) { };
 	};
 
@@ -385,6 +383,10 @@ namespace Genode {
 			 */
 			class Local_parent : public Expanding_parent_client
 			{
+				private:
+
+					Allocator &_alloc;
+
 				public:
 
 					/**********************
@@ -404,16 +406,30 @@ namespace Genode {
 					 *                    services
 					 */
 					Local_parent(Parent_capability parent_cap,
-					             Emergency_ram_reserve &);
+					             Emergency_ram_reserve &,
+					             Allocator &);
 			};
 
 			/**
 			 * Return instance of parent interface
 			 */
 			Local_parent &_parent();
 
+			Cap_session_capability _cap_session_cap;
+			Cap_session_client     _cap_session { _cap_session_cap };
+
+			Signal_session_capability _signal_session_cap;
+			Signal_session_client     _signal_session { _signal_session_cap };
+
 			Heap _heap;
 
+			/*
+			 * The '_heap' must be initialized before the '_context_area'
+			 * because the 'Local_parent' performs a dynamic memory allocation
+			 * due to the creation of the context area's sub-RM session.
+			 */
+			Attached_context_area _context_area;
+
 			/*
 			 * Emergency RAM reserve
 			 *
@@ -451,8 +467,15 @@ namespace Genode {
 			 ** Env interface **
 			 *******************/
 
-			Parent *parent() { return &_parent(); }
-			Heap   *heap()   { return &_heap; }
+			Parent         *parent()         override { return &_parent(); }
+			Heap           *heap()           override { return &_heap; }
+			Cap_session    *cap_session()    override { return &_cap_session; }
+			Signal_session *signal_session() override { return &_signal_session; }
+
+			Signal_session_capability signal_session_cap() override
+			{
+				return _signal_session_cap;
+			}
 	};
 }