genode/ports/include/vmm/vcpu_dispatcher.h
Norman Feske 1df48b8331 ports: common utilities for building VMMs on NOVA
To ease the creation of custom virtual machine monitors on top of
NOVA, this patch moves generic utilities from vancouver resp. seoul to the
public include location 'ports/include/vmm'. As a nice side effect,
this change simplifies 'vancouver/main.cc'.

Issue #949
2013-11-25 12:12:31 +01:00

119 lines
3.2 KiB
C++

/*
* \brief Utilities for implementing VMMs on Genode/NOVA
* \author Norman Feske
* \date 2013-08-20
*/
/*
* Copyright (C) 2013 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__VMM__VCPU_DISPATCHER_H_
#define _INCLUDE__VMM__VCPU_DISPATCHER_H_
namespace Vmm {
using namespace Genode;
class Vcpu_dispatcher;
}
/**
* Thread that handles virtualization events of a 'Vmm::Vcpu_thread'
*/
class Vmm::Vcpu_dispatcher : public Genode::Thread_base
{
private:
Cap_connection &_cap;
/**
* Portal entry point entered on virtualization events
*
* For each event type used as argument of the 'register_handler'
* function template, the compiler automatically generates a separate
* instance of this function. The sole purpose of this function is to
* call the 'Vcpu' member function corresponding to the event type.
*/
template <unsigned EV, typename DISPATCHER, void (DISPATCHER::*FUNC)()>
static void _portal_entry()
{
/* obtain this pointer of the event handler */
Genode::Thread_base *myself = Genode::Thread_base::myself();
DISPATCHER *vd = static_cast<DISPATCHER *>(myself);
/* call event-specific handler function */
(vd->*FUNC)();
/* continue execution of the guest */
Nova::reply(myself->stack_top());
}
public:
Vcpu_dispatcher(size_t stack_size, Cap_connection &cap)
:
Thread_base("vCPU dispatcher", stack_size),
_cap(cap)
{
using namespace Genode;
/* request creation of a 'local' EC */
_tid.ec_sel = Native_thread::INVALID_INDEX - 1;
Thread_base::start();
}
/**
* Register virtualization event handler
*/
template <unsigned EV, typename DISPATCHER, void (DISPATCHER::*FUNC)()>
bool register_handler(addr_t exc_base, Nova::Mtd mtd)
{
/*
* Let the compiler generate an instance of a portal entry
*/
void (*entry)() = &_portal_entry<EV, DISPATCHER, FUNC>;
/* Create the portal at the desired selector index */
_cap.rcv_window(exc_base + EV);
Native_capability thread_cap(tid().ec_sel);
Native_capability handler =
_cap.alloc(thread_cap, (Nova::mword_t)entry, mtd.value());
return handler.valid() && (exc_base + EV == handler.local_name());
}
/**
* Unused member of the 'Thread_base' interface
*
* Similarly to how 'Rpc_entrypoints' are handled, a 'Vcpu_dispatcher'
* comes with a custom initialization procedure, which does not call
* the thread's normal entry function. Instead, the thread's EC gets
* associated with several portals, each for handling a specific
* virtualization event.
*/
void entry() { }
/**
* Return capability selector of the VCPU's SM and EC
*
* The returned number corresponds to the VCPU's semaphore selector.
* The consecutive number corresponds to the EC. The number returned by
* this function is used by the VMM code as a unique identifier of the
* VCPU. I.e., it gets passed as arguments for 'MessageHostOp'
* operations.
*/
Nova::mword_t sel_sm_ec()
{
return tid().exc_pt_sel + Nova::SM_SEL_EC;
}
};
#endif /* _INCLUDE__VMM__VCPU_DISPATCHER_H_ */