Atmosphere/libraries/libmesosphere/source/kern_k_resource_limit.cpp

217 lines
7.7 KiB
C++

/*
* 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 {
namespace {
constexpr s64 DefaultTimeout = ams::svc::Tick(TimeSpan::FromSeconds(10));
}
void KResourceLimit::Initialize() {
m_waiter_count = 0;
std::memset(m_limit_values, 0, sizeof(m_limit_values));
std::memset(m_current_values, 0, sizeof(m_current_values));
std::memset(m_current_hints, 0, sizeof(m_current_hints));
std::memset(m_peak_values, 0, sizeof(m_peak_values));
}
void KResourceLimit::Finalize() {
/* ... */
}
s64 KResourceLimit::GetLimitValue(ams::svc::LimitableResource which) const {
MESOSPHERE_ASSERT_THIS();
s64 value;
{
KScopedLightLock lk(m_lock);
value = m_limit_values[which];
MESOSPHERE_ASSERT(value >= 0);
MESOSPHERE_ASSERT(m_current_values[which] <= m_peak_values[which]);
MESOSPHERE_ASSERT(m_peak_values[which] <= m_limit_values[which]);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
}
return value;
}
s64 KResourceLimit::GetCurrentValue(ams::svc::LimitableResource which) const {
MESOSPHERE_ASSERT_THIS();
s64 value;
{
KScopedLightLock lk(m_lock);
value = m_current_values[which];
MESOSPHERE_ASSERT(value >= 0);
MESOSPHERE_ASSERT(m_current_values[which] <= m_peak_values[which]);
MESOSPHERE_ASSERT(m_peak_values[which] <= m_limit_values[which]);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
}
return value;
}
s64 KResourceLimit::GetPeakValue(ams::svc::LimitableResource which) const {
MESOSPHERE_ASSERT_THIS();
s64 value;
{
KScopedLightLock lk(m_lock);
value = m_peak_values[which];
MESOSPHERE_ASSERT(value >= 0);
MESOSPHERE_ASSERT(m_current_values[which] <= m_peak_values[which]);
MESOSPHERE_ASSERT(m_peak_values[which] <= m_limit_values[which]);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
}
return value;
}
s64 KResourceLimit::GetFreeValue(ams::svc::LimitableResource which) const {
MESOSPHERE_ASSERT_THIS();
s64 value;
{
KScopedLightLock lk(m_lock);
MESOSPHERE_ASSERT(m_current_values[which] >= 0);
MESOSPHERE_ASSERT(m_current_values[which] <= m_peak_values[which]);
MESOSPHERE_ASSERT(m_peak_values[which] <= m_limit_values[which]);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
value = m_limit_values[which] - m_current_values[which];
}
return value;
}
Result KResourceLimit::SetLimitValue(ams::svc::LimitableResource which, s64 value) {
MESOSPHERE_ASSERT_THIS();
KScopedLightLock lk(m_lock);
R_UNLESS(m_current_values[which] <= value, svc::ResultInvalidState());
m_limit_values[which] = value;
m_peak_values[which] = m_current_values[which];
return ResultSuccess();
}
void KResourceLimit::Add(ams::svc::LimitableResource which, s64 value) {
MESOSPHERE_ASSERT_THIS();
MESOSPHERE_ASSERT(KTargetSystem::IsDynamicResourceLimitsEnabled());
KScopedLightLock lk(m_lock);
/* Check that this is a true increase. */
MESOSPHERE_ABORT_UNLESS(value > 0);
/* Check that we can perform an increase. */
MESOSPHERE_ABORT_UNLESS(m_current_values[which] <= m_peak_values[which]);
MESOSPHERE_ABORT_UNLESS(m_peak_values[which] <= m_limit_values[which]);
MESOSPHERE_ABORT_UNLESS(m_current_hints[which] <= m_current_values[which]);
/* Check that the increase doesn't cause an overflow. */
const auto increased_limit = m_limit_values[which] + value;
const auto increased_current = m_current_values[which] + value;
const auto increased_hint = m_current_hints[which] + value;
MESOSPHERE_ABORT_UNLESS(m_limit_values[which] < increased_limit);
MESOSPHERE_ABORT_UNLESS(m_current_values[which] < increased_current);
MESOSPHERE_ABORT_UNLESS(m_current_hints[which] < increased_hint);
/* Add the value. */
m_limit_values[which] = increased_limit;
m_current_values[which] = increased_current;
m_current_hints[which] = increased_hint;
/* Update our peak. */
m_peak_values[which] = std::max(m_peak_values[which], increased_current);
}
bool KResourceLimit::Reserve(ams::svc::LimitableResource which, s64 value) {
return this->Reserve(which, value, KHardwareTimer::GetTick() + DefaultTimeout);
}
bool KResourceLimit::Reserve(ams::svc::LimitableResource which, s64 value, s64 timeout) {
MESOSPHERE_ASSERT_THIS();
MESOSPHERE_ASSERT(value >= 0);
KScopedLightLock lk(m_lock);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
if (m_current_hints[which] >= m_limit_values[which]) {
return false;
}
/* Loop until we reserve or run out of time. */
while (true) {
MESOSPHERE_ASSERT(m_current_values[which] <= m_limit_values[which]);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
/* If we would overflow, don't allow to succeed. */
if (m_current_values[which] + value <= m_current_values[which]) {
break;
}
if (m_current_values[which] + value <= m_limit_values[which]) {
m_current_values[which] += value;
m_current_hints[which] += value;
m_peak_values[which] = std::max(m_peak_values[which], m_current_values[which]);
return true;
}
if (m_current_hints[which] + value <= m_limit_values[which] && (timeout < 0 || KHardwareTimer::GetTick() < timeout)) {
m_waiter_count++;
m_cond_var.Wait(std::addressof(m_lock), timeout, false);
m_waiter_count--;
if (GetCurrentThread().IsTerminationRequested()) {
return false;
}
} else {
break;
}
}
return false;
}
void KResourceLimit::Release(ams::svc::LimitableResource which, s64 value) {
this->Release(which, value, value);
}
void KResourceLimit::Release(ams::svc::LimitableResource which, s64 value, s64 hint) {
MESOSPHERE_ASSERT_THIS();
MESOSPHERE_ASSERT(value >= 0);
MESOSPHERE_ASSERT(hint >= 0);
KScopedLightLock lk(m_lock);
MESOSPHERE_ASSERT(m_current_values[which] <= m_limit_values[which]);
MESOSPHERE_ASSERT(m_current_hints[which] <= m_current_values[which]);
MESOSPHERE_ASSERT(value <= m_current_values[which]);
MESOSPHERE_ASSERT(hint <= m_current_hints[which]);
m_current_values[which] -= value;
m_current_hints[which] -= hint;
if (m_waiter_count != 0) {
m_cond_var.Broadcast();
}
}
}