genode/repos/base/include/ram_session/ram_session.h

118 lines
3.0 KiB
C++

/*
* \brief RAM session interface
* \author Norman Feske
* \date 2006-05-11
*/
/*
* Copyright (C) 2006-2017 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 _INCLUDE__RAM_SESSION__RAM_SESSION_H_
#define _INCLUDE__RAM_SESSION__RAM_SESSION_H_
#include <base/stdint.h>
#include <base/ram_allocator.h>
#include <dataspace/capability.h>
#include <ram_session/capability.h>
#include <session/session.h>
namespace Genode {
struct Ram_session_client;
struct Ram_session;
}
/**
* RAM session interface
*/
struct Genode::Ram_session : Session, Ram_allocator
{
static const char *service_name() { return "RAM"; }
enum { CAP_QUOTA = 8 };
typedef Ram_session_client Client;
/*********************
** Exception types **
*********************/
class Invalid_session : public Exception { };
class Undefined_ref_account : public Exception { };
/**
* Destructor
*/
virtual ~Ram_session() { }
/**
* Define reference account for the RAM session
*
* \param ram_session reference account
*
* \throw Invalid_session
*
* Each RAM session requires another RAM session as reference
* account to transfer quota to and from. The reference account can
* be defined only once.
*/
virtual void ref_account(Ram_session_capability ram_session) = 0;
/**
* Transfer quota to another RAM session
*
* \param ram_session receiver of quota donation
* \param amount amount of quota to donate
*
* \throw Out_of_ram
* \throw Invalid_session
* \throw Undefined_ref_account
*
* Quota can only be transfered if the specified RAM session is
* either the reference account for this session or vice versa.
*/
virtual void transfer_quota(Ram_session_capability ram_session, Ram_quota amount) = 0;
/**
* Return current quota limit
*/
virtual Ram_quota ram_quota() const = 0;
/**
* Return used quota
*/
virtual Ram_quota used_ram() const = 0;
/**
* Return amount of available quota
*/
Ram_quota avail_ram() const { return { ram_quota().value - used_ram().value }; }
/*********************
** RPC declaration **
*********************/
GENODE_RPC_THROW(Rpc_alloc, Ram_dataspace_capability, alloc,
GENODE_TYPE_LIST(Quota_exceeded, Out_of_metadata, Undefined_ref_account),
size_t, Cache_attribute);
GENODE_RPC(Rpc_free, void, free, Ram_dataspace_capability);
GENODE_RPC(Rpc_ref_account, void, ref_account, Capability<Ram_session>);
GENODE_RPC_THROW(Rpc_transfer_ram_quota, void, transfer_quota,
GENODE_TYPE_LIST(Out_of_ram, Invalid_session, Undefined_ref_account),
Capability<Ram_session>, Ram_quota);
GENODE_RPC(Rpc_ram_quota, Ram_quota, ram_quota);
GENODE_RPC(Rpc_used_ram, Ram_quota, used_ram);
GENODE_RPC_INTERFACE(Rpc_alloc, Rpc_free, Rpc_ref_account,
Rpc_transfer_ram_quota, Rpc_ram_quota, Rpc_used_ram);
};
#endif /* _INCLUDE__RAM_SESSION__RAM_SESSION_H_ */