2012-10-09 13:45:33 +02:00
|
|
|
/*
|
|
|
|
* \brief Child creation framework
|
|
|
|
* \author Norman Feske
|
|
|
|
* \date 2006-07-22
|
|
|
|
*/
|
|
|
|
|
|
|
|
/*
|
2013-01-10 21:44:47 +01:00
|
|
|
* Copyright (C) 2006-2013 Genode Labs GmbH
|
2012-10-09 13:45:33 +02:00
|
|
|
*
|
|
|
|
* This file is part of the Genode OS framework, which is distributed
|
|
|
|
* under the terms of the GNU General Public License version 2.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#include <base/child.h>
|
|
|
|
|
|
|
|
using namespace Genode;
|
|
|
|
|
|
|
|
|
|
|
|
/***************
|
|
|
|
** Utilities **
|
|
|
|
***************/
|
|
|
|
|
|
|
|
namespace {
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Guard for transferring quota donation
|
|
|
|
*
|
|
|
|
* This class is used to provide transactional semantics of quota
|
|
|
|
* transfers. Establishing a new session involves several steps, in
|
|
|
|
* particular subsequent quota transfers. If one intermediate step
|
|
|
|
* fails, we need to revert all quota transfers that already took
|
|
|
|
* place. When instantated at a local scope, a 'Transfer' object guards
|
|
|
|
* a quota transfer. If the scope is left without prior an explicit
|
|
|
|
* acknowledgement of the transfer (for example via an exception), the
|
|
|
|
* destructor the 'Transfer' object reverts the transfer in flight.
|
|
|
|
*/
|
|
|
|
class Transfer {
|
|
|
|
|
|
|
|
bool _ack;
|
|
|
|
size_t _quantum;
|
|
|
|
Ram_session_capability _from;
|
|
|
|
Ram_session_capability _to;
|
|
|
|
|
|
|
|
public:
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Constructor
|
|
|
|
*
|
|
|
|
* \param quantim number of bytes to transfer
|
|
|
|
* \param from donator RAM session
|
|
|
|
* \param to receiver RAM session
|
|
|
|
*/
|
|
|
|
Transfer(size_t quantum,
|
|
|
|
Ram_session_capability from,
|
|
|
|
Ram_session_capability to)
|
|
|
|
: _ack(false), _quantum(quantum), _from(from), _to(to)
|
|
|
|
{
|
|
|
|
if (_from.valid() && _to.valid() &&
|
|
|
|
Ram_session_client(_from).transfer_quota(_to, quantum)) {
|
|
|
|
PWRN("not enough quota for a donation of %zd bytes", quantum);
|
|
|
|
throw Parent::Quota_exceeded();
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Destructor
|
|
|
|
*
|
|
|
|
* The destructor will be called when leaving the scope of the
|
|
|
|
* 'session' function. If the scope is left because of an error
|
|
|
|
* (e.g., an exception), the donation will be reverted.
|
|
|
|
*/
|
|
|
|
~Transfer()
|
|
|
|
{
|
|
|
|
if (!_ack && _from.valid() && _to.valid())
|
|
|
|
Ram_session_client(_to).transfer_quota(_from, _quantum);
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Acknowledge quota donation
|
|
|
|
*/
|
|
|
|
void acknowledge() { _ack = true; }
|
|
|
|
};
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
/********************
|
|
|
|
** Child::Session **
|
|
|
|
********************/
|
|
|
|
|
|
|
|
class Child::Session : public Object_pool<Session>::Entry,
|
|
|
|
public List<Session>::Element
|
|
|
|
{
|
|
|
|
private:
|
|
|
|
|
|
|
|
enum { IDENT_LEN = 16 };
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Session capability at the server
|
|
|
|
*/
|
|
|
|
Session_capability _cap;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Service interface that was used to create the session
|
|
|
|
*/
|
|
|
|
Service *_service;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Server implementing the session
|
|
|
|
*
|
|
|
|
* Even though we can normally determine the server of the session via
|
|
|
|
* '_service->server()', this does not apply when destructing a server.
|
|
|
|
* During destruction, we use the 'Server' pointer as opaque key for
|
|
|
|
* revoking active sessions of the server. So we keep a copy
|
|
|
|
* independent of the 'Service' object.
|
|
|
|
*/
|
|
|
|
Server *_server;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Total of quota associated with this session
|
|
|
|
*/
|
|
|
|
size_t _donated_ram_quota;
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Name of session, used for debugging
|
|
|
|
*/
|
|
|
|
char _ident[IDENT_LEN];
|
|
|
|
|
|
|
|
public:
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Constructor
|
|
|
|
*
|
|
|
|
* \param session session capability
|
|
|
|
* \param service service that implements the session
|
|
|
|
* \param ram_quota initial quota donation associated with
|
|
|
|
* the session
|
|
|
|
* \param ident optional session identifier, used for
|
|
|
|
* debugging
|
|
|
|
*/
|
|
|
|
Session(Session_capability session, Service *service,
|
|
|
|
size_t ram_quota, const char *ident = "<noname>")
|
|
|
|
:
|
|
|
|
Object_pool<Session>::Entry(session), _cap(session),
|
|
|
|
_service(service), _server(service->server()),
|
|
|
|
_donated_ram_quota(ram_quota) {
|
|
|
|
strncpy(_ident, ident, sizeof(_ident)); }
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Default constructor creates invalid session
|
|
|
|
*/
|
|
|
|
Session() : _service(0), _donated_ram_quota(0) { }
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Extend amount of ram attached to the session
|
|
|
|
*/
|
|
|
|
void upgrade_ram_quota(size_t ram_quota) {
|
|
|
|
_donated_ram_quota += ram_quota; }
|
|
|
|
|
|
|
|
/**
|
|
|
|
* Accessors
|
|
|
|
*/
|
|
|
|
Session_capability cap() const { return _cap; }
|
|
|
|
size_t donated_ram_quota() const { return _donated_ram_quota; }
|
|
|
|
bool valid() const { return _service != 0; }
|
|
|
|
Service *service() const { return _service; }
|
|
|
|
Server *server() const { return _server; }
|
|
|
|
const char *ident() const { return _ident; }
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
|
|
/***********
|
|
|
|
** Child **
|
|
|
|
***********/
|
|
|
|
|
|
|
|
void Child::_add_session(Child::Session const &s)
|
|
|
|
{
|
|
|
|
Lock::Guard lock_guard(_lock);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Store session information in a new child's meta data structure. The
|
|
|
|
* allocation from 'heap()' may throw a 'Ram_session::Quota_exceeded'
|
|
|
|
* exception.
|
|
|
|
*/
|
|
|
|
Session *session = 0;
|
|
|
|
try {
|
|
|
|
session = new (heap())
|
|
|
|
Session(s.cap(), s.service(),
|
|
|
|
s.donated_ram_quota(), s.ident()); }
|
|
|
|
catch (Allocator::Out_of_memory) {
|
|
|
|
throw Parent::Quota_exceeded(); }
|
|
|
|
|
|
|
|
/* these functions may also throw 'Ram_session::Quota_exceeded' */
|
|
|
|
_session_pool.insert(session);
|
|
|
|
_session_list.insert(session);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Child::_remove_session(Child::Session *s)
|
|
|
|
{
|
|
|
|
/* forget about this session */
|
2012-12-14 10:03:55 +01:00
|
|
|
_session_pool.remove_locked(s);
|
2012-10-09 13:45:33 +02:00
|
|
|
_session_list.remove(s);
|
|
|
|
|
|
|
|
/* return session quota to the ram session of the child */
|
|
|
|
if (_policy->ref_ram_session()->transfer_quota(_ram, s->donated_ram_quota()))
|
|
|
|
PERR("We ran out of our own quota");
|
|
|
|
|
|
|
|
destroy(heap(), s);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
Service *Child::_parent_service()
|
|
|
|
{
|
|
|
|
static Parent_service parent_service("");
|
|
|
|
return &parent_service;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Child::revoke_server(Server const *server)
|
|
|
|
{
|
|
|
|
Lock::Guard lock_guard(_lock);
|
|
|
|
|
|
|
|
while (1) {
|
|
|
|
/* search session belonging to the specified server */
|
|
|
|
Session *s = _session_list.first();
|
|
|
|
for ( ; s && (s->server() != server); s = s->next());
|
|
|
|
|
|
|
|
/* if no matching session exists, we are done */
|
|
|
|
if (!s) return;
|
|
|
|
|
|
|
|
_remove_session(s);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Child::announce(Parent::Service_name const &name, Root_capability root)
|
|
|
|
{
|
|
|
|
if (!name.is_valid_string()) return;
|
|
|
|
|
|
|
|
_policy->announce_service(name.string(), root, heap(), &_server);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
Session_capability Child::session(Parent::Service_name const &name,
|
2013-08-07 23:10:28 +02:00
|
|
|
Parent::Session_args const &args,
|
|
|
|
Affinity const &affinity)
|
2012-10-09 13:45:33 +02:00
|
|
|
{
|
|
|
|
if (!name.is_valid_string() || !args.is_valid_string()) throw Unavailable();
|
|
|
|
|
|
|
|
/* return sessions that we created for the child */
|
|
|
|
if (!strcmp("Env::ram_session", name.string())) return _ram;
|
|
|
|
if (!strcmp("Env::cpu_session", name.string())) return _cpu;
|
|
|
|
if (!strcmp("Env::rm_session", name.string())) return _rm;
|
|
|
|
if (!strcmp("Env::pd_session", name.string())) return _process.pd_session_cap();
|
|
|
|
|
|
|
|
/* filter session arguments according to the child policy */
|
|
|
|
strncpy(_args, args.string(), sizeof(_args));
|
|
|
|
_policy->filter_session_args(name.string(), _args, sizeof(_args));
|
|
|
|
|
|
|
|
/* transfer the quota donation from the child's account to ourself */
|
|
|
|
size_t ram_quota = Arg_string::find_arg(_args, "ram_quota").long_value(0);
|
|
|
|
|
|
|
|
Transfer donation_from_child(ram_quota, _ram, env()->ram_session_cap());
|
|
|
|
|
|
|
|
Service *service = _policy->resolve_session_request(name.string(), _args);
|
|
|
|
|
|
|
|
/* raise an error if no matching service provider could be found */
|
|
|
|
if (!service)
|
|
|
|
throw Service_denied();
|
|
|
|
|
|
|
|
/* transfer session quota from ourself to the service provider */
|
|
|
|
Transfer donation_to_service(ram_quota, env()->ram_session_cap(),
|
|
|
|
service->ram_session_cap());
|
|
|
|
|
|
|
|
/* create session */
|
|
|
|
Session_capability cap;
|
2013-08-07 23:10:28 +02:00
|
|
|
try { cap = service->session(_args, affinity); }
|
2012-10-09 13:45:33 +02:00
|
|
|
catch (Service::Invalid_args) { throw Service_denied(); }
|
|
|
|
catch (Service::Unavailable) { throw Service_denied(); }
|
|
|
|
catch (Service::Quota_exceeded) { throw Quota_exceeded(); }
|
|
|
|
|
|
|
|
/* register session */
|
|
|
|
try { _add_session(Session(cap, service, ram_quota, name.string())); }
|
|
|
|
catch (Ram_session::Quota_exceeded) { throw Quota_exceeded(); }
|
|
|
|
|
|
|
|
/* finish transaction */
|
|
|
|
donation_from_child.acknowledge();
|
|
|
|
donation_to_service.acknowledge();
|
|
|
|
|
|
|
|
return cap;
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Child::upgrade(Session_capability to_session, Parent::Upgrade_args const &args)
|
|
|
|
{
|
|
|
|
Service *targeted_service = 0;
|
|
|
|
|
|
|
|
/* check of upgrade refers to an Env:: resource */
|
|
|
|
if (to_session.local_name() == _ram.local_name())
|
|
|
|
targeted_service = &_ram_service;
|
|
|
|
if (to_session.local_name() == _cpu.local_name())
|
|
|
|
targeted_service = &_cpu_service;
|
|
|
|
if (to_session.local_name() == _rm.local_name())
|
|
|
|
targeted_service = &_rm_service;
|
|
|
|
|
|
|
|
/* check if upgrade refers to server */
|
2012-12-14 10:03:55 +01:00
|
|
|
Object_pool<Session>::Guard session(_session_pool.lookup_and_lock(to_session));
|
2012-10-09 13:45:33 +02:00
|
|
|
if (session)
|
|
|
|
targeted_service = session->service();
|
|
|
|
|
|
|
|
if (!targeted_service) {
|
|
|
|
PWRN("could not lookup service for session upgrade");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (!args.is_valid_string()) {
|
|
|
|
PWRN("no valid session-upgrade arguments");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
size_t const ram_quota =
|
|
|
|
Arg_string::find_arg(args.string(), "ram_quota").ulong_value(0);
|
|
|
|
|
|
|
|
/* transfer quota from client to ourself */
|
|
|
|
Transfer donation_from_child(ram_quota, _ram,
|
|
|
|
env()->ram_session_cap());
|
|
|
|
|
|
|
|
/* transfer session quota from ourself to the service provider */
|
|
|
|
Transfer donation_to_service(ram_quota, env()->ram_session_cap(),
|
|
|
|
targeted_service->ram_session_cap());
|
|
|
|
|
|
|
|
try { targeted_service->upgrade(to_session, args.string()); }
|
|
|
|
catch (Service::Quota_exceeded) { throw Quota_exceeded(); }
|
|
|
|
|
|
|
|
/* remember new amount attached to the session */
|
|
|
|
if (session)
|
|
|
|
session->upgrade_ram_quota(ram_quota);
|
|
|
|
|
|
|
|
/* finish transaction */
|
|
|
|
donation_from_child.acknowledge();
|
|
|
|
donation_to_service.acknowledge();
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Child::close(Session_capability session_cap)
|
|
|
|
{
|
|
|
|
/* refuse to close the child's initial sessions */
|
|
|
|
if (session_cap.local_name() == _ram.local_name()
|
|
|
|
|| session_cap.local_name() == _cpu.local_name()
|
|
|
|
|| session_cap.local_name() == _rm.local_name()
|
|
|
|
|| session_cap.local_name() == _process.pd_session_cap().local_name())
|
|
|
|
return;
|
|
|
|
|
2012-12-14 10:03:55 +01:00
|
|
|
Session *s = _session_pool.lookup_and_lock(session_cap);
|
2012-10-09 13:45:33 +02:00
|
|
|
|
|
|
|
if (!s) {
|
|
|
|
PWRN("no session structure found");
|
|
|
|
return;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* There is a chance that the server is not responding to the 'close' call,
|
|
|
|
* making us block infinitely. However, by using core's cancel-blocking
|
|
|
|
* mechanism, we can cancel the 'close' call by another (watchdog) thread
|
|
|
|
* that invokes 'cancel_blocking' at our thread after a timeout. The
|
|
|
|
* unblocking is reflected at the API level as an 'Blocking_canceled'
|
|
|
|
* exception. We catch this exception to proceed with normal operation
|
|
|
|
* after being unblocked.
|
|
|
|
*/
|
|
|
|
try { s->service()->close(s->cap()); }
|
|
|
|
catch (Blocking_canceled) {
|
|
|
|
PDBG("Got Blocking_canceled exception during %s->close call\n",
|
|
|
|
s->ident()); }
|
|
|
|
|
|
|
|
/*
|
|
|
|
* If the session was provided by a child of us,
|
|
|
|
* 'server()->ram_session_cap()' returns the RAM session of the
|
|
|
|
* corresponding child. Since the session to the server is closed now, we
|
|
|
|
* expect that the server released all donated resources and we can
|
|
|
|
* decrease the servers' quota.
|
|
|
|
*
|
|
|
|
* If this goes wrong, the server is misbehaving.
|
|
|
|
*/
|
|
|
|
if (s->service()->ram_session_cap().valid()) {
|
|
|
|
Ram_session_client server_ram(s->service()->ram_session_cap());
|
|
|
|
if (server_ram.transfer_quota(env()->ram_session_cap(),
|
|
|
|
s->donated_ram_quota())) {
|
|
|
|
PERR("Misbehaving server '%s'!", s->service()->name());
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
Lock::Guard lock_guard(_lock);
|
|
|
|
_remove_session(s);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
|
|
void Child::exit(int exit_value)
|
|
|
|
{
|
|
|
|
/*
|
|
|
|
* This function receives the hint from the child that now, its a good time
|
|
|
|
* to kill it. An inherited child class could use this hint to schedule the
|
|
|
|
* destruction of the child object.
|
|
|
|
*
|
|
|
|
* Note that the child object must not be destructed from by this function
|
|
|
|
* because it is executed by the thread contained in the child object.
|
|
|
|
*/
|
|
|
|
return _policy->exit(exit_value);
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2012-10-10 13:05:54 +02:00
|
|
|
Thread_capability Child::main_thread_cap() const
|
|
|
|
{
|
|
|
|
return _process.main_thread_cap();
|
|
|
|
}
|
|
|
|
|
|
|
|
|
2012-10-09 13:45:33 +02:00
|
|
|
Child::Child(Dataspace_capability elf_ds,
|
|
|
|
Ram_session_capability ram,
|
|
|
|
Cpu_session_capability cpu,
|
|
|
|
Rm_session_capability rm,
|
|
|
|
Rpc_entrypoint *entrypoint,
|
|
|
|
Child_policy *policy,
|
|
|
|
Service &ram_service,
|
|
|
|
Service &cpu_service,
|
|
|
|
Service &rm_service)
|
|
|
|
:
|
|
|
|
_ram(ram), _ram_session_client(ram), _cpu(cpu), _rm(rm),
|
|
|
|
_ram_service(ram_service), _cpu_service(cpu_service),
|
|
|
|
_rm_service(rm_service),
|
|
|
|
_heap(&_ram_session_client, env()->rm_session()),
|
|
|
|
_entrypoint(entrypoint),
|
|
|
|
_parent_cap(_entrypoint->manage(this)),
|
|
|
|
_policy(policy),
|
|
|
|
_server(ram),
|
2012-11-21 15:20:21 +01:00
|
|
|
_process(elf_ds, ram, cpu, rm, _parent_cap, policy->name(), policy->pd_args())
|
2012-10-09 13:45:33 +02:00
|
|
|
{ }
|
|
|
|
|
|
|
|
|
|
|
|
Child::~Child()
|
|
|
|
{
|
|
|
|
_entrypoint->dissolve(this);
|
|
|
|
_policy->unregister_services();
|
|
|
|
|
|
|
|
for (Session *s; (s = _session_pool.first()); )
|
|
|
|
close(s->cap());
|
|
|
|
}
|
|
|
|
|