genode/repos/os/include/nic/root.h
2019-02-19 11:12:11 +01:00

76 lines
2.1 KiB
C++

/**
* \brief Simple single client NIC Root
* \author Sebastian Sumpf
* \date 2015-06-23
*/
/*
* Copyright (C) 2015-2017 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__NIC__ROOT_H_
#define _INCLUDE__NIC__ROOT_H_
#include <nic/component.h>
#include <root/component.h>
namespace Nic {
using namespace Genode;
template <class SESSION_COMPONENT> class Root;
};
template <class SESSION_COMPONENT>
class Nic::Root : public Genode::Root_component<SESSION_COMPONENT,
Genode::Single_client>
{
private:
Env &_env;
Allocator &_md_alloc;
protected:
SESSION_COMPONENT *_create_session(const char *args) override
{
using namespace Genode;
size_t ram_quota = Arg_string::find_arg(args, "ram_quota" ).ulong_value(0);
size_t tx_buf_size = Arg_string::find_arg(args, "tx_buf_size").ulong_value(0);
size_t rx_buf_size = Arg_string::find_arg(args, "rx_buf_size").ulong_value(0);
/* deplete ram quota by the memory needed for the session structure */
size_t session_size = max(4096UL, (unsigned long)sizeof(SESSION_COMPONENT));
if (ram_quota < session_size)
throw Genode::Insufficient_ram_quota();
/*
* Check if donated ram quota suffices for both communication
* buffers and check for overflow
*/
if (tx_buf_size + rx_buf_size < tx_buf_size ||
tx_buf_size + rx_buf_size > ram_quota - session_size) {
Genode::error("insufficient 'ram_quota', got ", ram_quota, ", "
"need ", tx_buf_size + rx_buf_size + session_size);
throw Genode::Insufficient_ram_quota();
}
return new (Root::md_alloc())
SESSION_COMPONENT(tx_buf_size, rx_buf_size,
_md_alloc, _env);
}
public:
Root(Genode::Env &env, Genode::Allocator &md_alloc)
: Genode::Root_component<SESSION_COMPONENT, Genode::Single_client>(&env.ep().rpc_ep(), &md_alloc),
_env(env), _md_alloc(md_alloc)
{ }
};
#endif /* _INCLUDE__NIC__ROOT_H_ */