4773707495
By separating the session-interface concerns from the mechanics of the dataspace creation, the code becomes simpler to follow, and the RAM session can be more easily merged with the PD session in a subsequent step. Issue #2407
118 lines
3.0 KiB
C++
118 lines
3.0 KiB
C++
/*
|
|
* \brief RAM dataspace factory
|
|
* \author Norman Feske
|
|
* \date 2017-05-11
|
|
*/
|
|
|
|
/*
|
|
* Copyright (C) 2017 Genode Labs GmbH
|
|
*
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
* under the terms of the GNU Affero General Public License version 3.
|
|
*/
|
|
|
|
#ifndef _CORE__INCLUDE__RAM_DATASPACE_FACTORY_H_
|
|
#define _CORE__INCLUDE__RAM_DATASPACE_FACTORY_H_
|
|
|
|
/* Genode includes */
|
|
#include <base/heap.h>
|
|
#include <base/tslab.h>
|
|
|
|
/* base-internal includes */
|
|
#include <base/internal/page_size.h>
|
|
|
|
/* core includes */
|
|
#include <dataspace_component.h>
|
|
|
|
namespace Genode { class Ram_dataspace_factory; }
|
|
|
|
|
|
class Genode::Ram_dataspace_factory : public Ram_allocator,
|
|
public Dataspace_owner
|
|
{
|
|
public:
|
|
|
|
struct Phys_range { addr_t start, end; };
|
|
|
|
static Phys_range any_phys_range() { return { 0UL, ~0UL }; }
|
|
|
|
/*
|
|
* Dimension '_ds_slab' such that slab blocks (including the
|
|
* meta-data overhead of the sliced-heap blocks) are page sized.
|
|
*/
|
|
static constexpr size_t SLAB_BLOCK_SIZE =
|
|
get_page_size() - Sliced_heap::meta_data_size();
|
|
|
|
private:
|
|
|
|
Rpc_entrypoint &_ep;
|
|
|
|
Range_allocator &_phys_alloc;
|
|
Phys_range const _phys_range;
|
|
|
|
|
|
/*
|
|
* Statically allocated initial slab block for '_ds_slab', needed to
|
|
* untangle the hen-and-egg problem of allocating the meta data for
|
|
* core's RAM allocator from itself. I also saves the allocation
|
|
* of one dataspace (along with a dataspace capability) per session.
|
|
*/
|
|
uint8_t _initial_sb[SLAB_BLOCK_SIZE];
|
|
|
|
Tslab<Dataspace_component, SLAB_BLOCK_SIZE> _ds_slab;
|
|
|
|
|
|
/********************************************
|
|
** Platform-implemented support functions **
|
|
********************************************/
|
|
|
|
struct Core_virtual_memory_exhausted : Exception { };
|
|
|
|
/**
|
|
* Export RAM dataspace as shared memory block
|
|
*
|
|
* \throw Core_virtual_memory_exhausted
|
|
*/
|
|
void _export_ram_ds(Dataspace_component *ds);
|
|
|
|
/**
|
|
* Revert export of RAM dataspace
|
|
*/
|
|
void _revoke_ram_ds(Dataspace_component *ds);
|
|
|
|
/**
|
|
* Zero-out content of dataspace
|
|
*/
|
|
void _clear_ds(Dataspace_component *ds);
|
|
|
|
public:
|
|
|
|
Ram_dataspace_factory(Rpc_entrypoint &ep,
|
|
Range_allocator &phys_alloc,
|
|
Phys_range phys_range,
|
|
Region_map &local_rm,
|
|
Sliced_heap &sliced_heap)
|
|
:
|
|
_ep(ep), _phys_alloc(phys_alloc), _phys_range(phys_range),
|
|
_ds_slab(sliced_heap, _initial_sb)
|
|
{ }
|
|
|
|
~Ram_dataspace_factory()
|
|
{
|
|
while (Dataspace_component *ds = _ds_slab.first_object())
|
|
free(static_cap_cast<Ram_dataspace>(
|
|
static_cap_cast<Dataspace>(ds->cap())));
|
|
}
|
|
|
|
|
|
/*****************************
|
|
** Ram_allocator interface **
|
|
*****************************/
|
|
|
|
Ram_dataspace_capability alloc(size_t, Cache_attribute) override;
|
|
void free(Ram_dataspace_capability) override;
|
|
size_t dataspace_size(Ram_dataspace_capability ds) const override;
|
|
};
|
|
|
|
#endif /* _CORE__INCLUDE__RAM_DATASPACE_FACTORY_H_ */
|