genode/repos/base-nova/src/core/include/signal_broker.h

136 lines
3.6 KiB
C++

/*
* \brief NOVA-specific signal-delivery mechanism
* \author Norman Feske
* \date 2016-01-04
*/
/*
* 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 _CORE__INCLUDE__SIGNAL_BROKER_H_
#define _CORE__INCLUDE__SIGNAL_BROKER_H_
/* Genode includes */
#include <base/tslab.h>
/* core-local includes */
#include <signal_source_component.h>
#include <signal_source/capability.h>
namespace Genode { class Signal_broker; }
class Genode::Signal_broker
{
private:
Allocator &_md_alloc;
Rpc_entrypoint &_source_ep;
Object_pool<Signal_context_component> _obj_pool;
Rpc_entrypoint &_context_ep;
Signal_source_component _source;
Signal_source_capability _source_cap;
Tslab<Signal_context_component,
960*sizeof(long)> _contexts_slab { &_md_alloc };
public:
class Invalid_signal_source : public Exception { };
Signal_broker(Allocator &md_alloc,
Rpc_entrypoint &source_ep,
Rpc_entrypoint &context_ep)
:
_md_alloc(md_alloc),
_source_ep(source_ep),
_context_ep(context_ep),
_source(&_context_ep),
_source_cap(_source_ep.manage(&_source))
{ }
~Signal_broker()
{
/* remove source from entrypoint */
_source_ep.dissolve(&_source);
/* free all signal contexts */
while (Signal_context_component *r = _contexts_slab.first_object())
free_context(reinterpret_cap_cast<Signal_context>(r->cap()));
}
Signal_source_capability alloc_signal_source() { return _source_cap; }
void free_signal_source(Signal_source_capability) { }
/*
* \throw Allocator::Out_of_memory
*/
Signal_context_capability
alloc_context(Signal_source_capability, unsigned long imprint)
{
/*
* XXX For now, we ignore the signal-source argument as we
* create only a single receiver for each PD.
*/
Native_capability sm = _source.blocking_semaphore();
if (!sm.valid()) {
PWRN("signal receiver sm is not valid");
for (;;);
return Signal_context_capability();
}
Native_capability si(cap_map()->insert());
Signal_context_capability cap = reinterpret_cap_cast<Signal_context>(si);
uint8_t res = Nova::create_si(cap.local_name(), __core_pd_sel, imprint,
sm.local_name());
if (res != Nova::NOVA_OK) {
PWRN("creating signal failed - error %u", res);
return Signal_context_capability();
}
/* the _contexts_slab may throw Allocator::Out_of_memory */
_obj_pool.insert(new (&_contexts_slab) Signal_context_component(cap));
/* return unique capability for the signal context */
return cap;
}
void free_context(Signal_context_capability context_cap)
{
Signal_context_component *context;
auto lambda = [&] (Signal_context_component *c) {
context = c;
if (context) _obj_pool.remove(context);
};
_obj_pool.apply(context_cap, lambda);
if (!context) {
PWRN("%p - specified signal-context capability has wrong type %lx",
this, context_cap.local_name());
return;
}
destroy(&_contexts_slab, context);
Nova::revoke(Nova::Obj_crd(context_cap.local_name(), 0));
cap_map()->remove(context_cap.local_name(), 0);
}
void submit(Signal_context_capability cap, unsigned cnt)
{
/*
* On NOVA, signals are submitted directly to the kernel, not
* by using core as a proxy.
*/
ASSERT_NEVER_CALLED;
}
};
#endif /* _CORE__INCLUDE__SIGNAL_BROKER_H_ */