/*
* Copyright (c) Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <mesosphere.hpp>
namespace ams::kern {
void KClientPort::Initialize(KPort *parent, s32 max_sessions) {
/* Set member variables. */
m_num_sessions = 0;
m_peak_sessions = 0;
m_parent = parent;
m_max_sessions = max_sessions;
}
void KClientPort::OnSessionFinalized() {
KScopedSchedulerLock sl;
if (m_num_sessions.FetchSub(1) == m_max_sessions) {
this->NotifyAvailable();
}
}
void KClientPort::OnServerClosed() {
MESOSPHERE_ASSERT_THIS();
}
bool KClientPort::IsLight() const {
return this->GetParent()->IsLight();
}
bool KClientPort::IsServerClosed() const {
return this->GetParent()->IsServerClosed();
}
void KClientPort::Destroy() {
/* Note with our parent that we're closed. */
m_parent->OnClientClosed();
/* Close our reference to our parent. */
m_parent->Close();
}
bool KClientPort::IsSignaled() const {
MESOSPHERE_ASSERT_THIS();
return m_num_sessions.Load() < m_max_sessions;
}
Result KClientPort::CreateSession(KClientSession **out) {
MESOSPHERE_ASSERT_THIS();
/* Declare the session we're going to allocate. */
KSession *session;
/* Reserve a new session from the resource limit. */
KScopedResourceReservation session_reservation(GetCurrentProcessPointer(), ams::svc::LimitableResource_SessionCountMax);
if (session_reservation.Succeeded()) {
/* Allocate a session normally. */
session = KSession::Create();
} else {
/* We couldn't reserve a session. Check that we support dynamically expanding the resource limit. */
R_UNLESS(GetCurrentProcess().GetResourceLimit() == std::addressof(Kernel::GetSystemResourceLimit()), svc::ResultLimitReached());
R_UNLESS(KTargetSystem::IsDynamicResourceLimitsEnabled(), svc::ResultLimitReached());
/* Try to allocate a session from unused slab memory. */
session = KSession::CreateFromUnusedSlabMemory();
R_UNLESS(session != nullptr, svc::ResultLimitReached());
/* Ensure that if we fail to allocate our session requests, we close the session we created. */
auto session_guard = SCOPE_GUARD { session->Close(); };
{
/* We want to add two KSessionRequests to the heap, to prevent request exhaustion. */
for (size_t i = 0; i < 2; ++i) {
KSessionRequest *request = KSessionRequest::CreateFromUnusedSlabMemory();
R_UNLESS(request != nullptr, svc::ResultLimitReached());
request->Close();
}
}
session_guard.Cancel();
/* We successfully allocated a session, so add the object we allocated to the resource limit. */
Kernel::GetSystemResourceLimit().Add(ams::svc::LimitableResource_SessionCountMax, 1);
}
/* Check that we successfully created a session. */
R_UNLESS(session != nullptr, svc::ResultOutOfResource());
/* Update the session counts. */
auto count_guard = SCOPE_GUARD { session->Close(); };
{
/* Atomically increment the number of sessions. */
s32 new_sessions;
{
const auto max = m_max_sessions;
auto cur_sessions = m_num_sessions.Load();
do {
R_UNLESS(cur_sessions < max, svc::ResultOutOfSessions());
new_sessions = cur_sessions + 1;
} while (!m_num_sessions.CompareExchangeWeak<std::memory_order_relaxed>(cur_sessions, new_sessions));
}
/* Atomically update the peak session tracking. */
{
auto peak = m_peak_sessions.Load();
do {
if (peak >= new_sessions) {
break;
}
} while (!m_peak_sessions.CompareExchangeWeak<std::memory_order_relaxed>(peak, new_sessions));
}
}
count_guard.Cancel();
/* Initialize the session. */
session->Initialize(this, m_parent->GetName());
/* Commit the session reservation. */
session_reservation.Commit();
/* Register the session. */
KSession::Register(session);
auto session_guard = SCOPE_GUARD {
session->GetClientSession().Close();
session->GetServerSession().Close();
};
/* Enqueue the session with our parent. */
R_TRY(m_parent->EnqueueSession(std::addressof(session->GetServerSession())));
/* We succeeded, so set the output. */
session_guard.Cancel();
*out = std::addressof(session->GetClientSession());
return ResultSuccess();
}
Result KClientPort::CreateLightSession(KLightClientSession **out) {
MESOSPHERE_ASSERT_THIS();
/* Declare the session we're going to allocate. */
KLightSession *session;
/* Reserve a new session from the resource limit. */
KScopedResourceReservation session_reservation(GetCurrentProcessPointer(), ams::svc::LimitableResource_SessionCountMax);
if (session_reservation.Succeeded()) {
/* Allocate a session normally. */
session = KLightSession::Create();
} else {
/* We couldn't reserve a session. Check that we support dynamically expanding the resource limit. */
R_UNLESS(GetCurrentProcess().GetResourceLimit() == std::addressof(Kernel::GetSystemResourceLimit()), svc::ResultLimitReached());
R_UNLESS(KTargetSystem::IsDynamicResourceLimitsEnabled(), svc::ResultLimitReached());
/* Try to allocate a session from unused slab memory. */
session = KLightSession::CreateFromUnusedSlabMemory();
R_UNLESS(session != nullptr, svc::ResultLimitReached());
/* We successfully allocated a session, so add the object we allocated to the resource limit. */
Kernel::GetSystemResourceLimit().Add(ams::svc::LimitableResource_SessionCountMax, 1);
}
/* Check that we successfully created a session. */
R_UNLESS(session != nullptr, svc::ResultOutOfResource());
/* Update the session counts. */
auto count_guard = SCOPE_GUARD { session->Close(); };
{
/* Atomically increment the number of sessions. */
s32 new_sessions;
{
const auto max = m_max_sessions;
auto cur_sessions = m_num_sessions.Load();
do {
R_UNLESS(cur_sessions < max, svc::ResultOutOfSessions());
new_sessions = cur_sessions + 1;
} while (!m_num_sessions.CompareExchangeWeak<std::memory_order_relaxed>(cur_sessions, new_sessions));
}
/* Atomically update the peak session tracking. */
{
auto peak = m_peak_sessions.Load();
do {
if (peak >= new_sessions) {
break;
}
} while (!m_peak_sessions.CompareExchangeWeak<std::memory_order_relaxed>(peak, new_sessions));
}
}
count_guard.Cancel();
/* Initialize the session. */
session->Initialize(this, m_parent->GetName());
/* Commit the session reservation. */
session_reservation.Commit();
/* Register the session. */
KLightSession::Register(session);
auto session_guard = SCOPE_GUARD {
session->GetClientSession().Close();
session->GetServerSession().Close();
};
/* Enqueue the session with our parent. */
R_TRY(m_parent->EnqueueSession(std::addressof(session->GetServerSession())));
/* We succeeded, so set the output. */
session_guard.Cancel();
*out = std::addressof(session->GetClientSession());
return ResultSuccess();
}
}
