From 1b7d619914c8d132dbffb8b6a5bb3a1aab686f9d Mon Sep 17 00:00:00 2001
From: Zach Hilman <zachhilman@gmail.com>
Date: Thu, 30 May 2019 08:52:20 -0400
Subject: [PATCH 1/4] memory: Add class to manage and enforce memory freezing
---
src/core/CMakeLists.txt | 2 +
src/core/core.cpp | 2 +
src/core/memory/freezer.cpp | 186 ++++++++++++++++++++++++++++++++++++
src/core/memory/freezer.h | 58 +++++++++++
4 files changed, 248 insertions(+)
create mode 100644 src/core/memory/freezer.cpp
create mode 100644 src/core/memory/freezer.h
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 4204ace2b..c17528134 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -454,6 +454,8 @@ add_library(core STATIC
loader/nsp.h
loader/xci.cpp
loader/xci.h
+ memory/freezer.cpp
+ memory/freezer.h
memory.cpp
memory.h
memory_setup.h
diff --git a/src/core/core.cpp b/src/core/core.cpp
index ff0721079..94ebe0995 100644
--- a/src/core/core.cpp
+++ b/src/core/core.cpp
@@ -28,6 +28,7 @@
#include "core/hle/service/service.h"
#include "core/hle/service/sm/sm.h"
#include "core/loader/loader.h"
+#include "core/memory/freezer.h"
#include "core/perf_stats.h"
#include "core/settings.h"
#include "core/telemetry_session.h"
@@ -243,6 +244,7 @@ struct System::Impl {
bool is_powered_on = false;
std::unique_ptr<FileSys::CheatEngine> cheat_engine;
+ std::unique_ptr<Memory::Freezer> memory_freezer;
/// Frontend applets
Service::AM::Applets::AppletManager applet_manager;
diff --git a/src/core/memory/freezer.cpp b/src/core/memory/freezer.cpp
new file mode 100644
index 000000000..1d0ccf328
--- /dev/null
+++ b/src/core/memory/freezer.cpp
@@ -0,0 +1,186 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/assert.h"
+#include "core/core.h"
+#include "core/core_timing_util.h"
+#include "core/memory.h"
+#include "core/memory/freezer.h"
+
+namespace Memory {
+
+constexpr s64 MEMORY_FREEZER_TICKS = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 60);
+
+namespace {
+
+u64 MemoryReadWidth(u8 width, VAddr addr) {
+ switch (width) {
+ case 1:
+ return Read8(addr);
+ case 2:
+ return Read16(addr);
+ case 4:
+ return Read32(addr);
+ case 8:
+ return Read64(addr);
+ default:
+ UNREACHABLE();
+ return 0;
+ }
+}
+
+void MemoryWriteWidth(u8 width, VAddr addr, u64 value) {
+ switch (width) {
+ case 1:
+ Write8(addr, static_cast<u8>(value));
+ break;
+ case 2:
+ Write16(addr, static_cast<u16>(value));
+ break;
+ case 4:
+ Write32(addr, static_cast<u32>(value));
+ break;
+ case 8:
+ Write64(addr, value);
+ break;
+ default:
+ UNREACHABLE();
+ }
+}
+
+} // Anonymous namespace
+
+Freezer::Freezer(Core::Timing::CoreTiming& core_timing) : core_timing(core_timing) {
+ event = core_timing.RegisterEvent(
+ "MemoryFreezer::FrameCallback",
+ [this](u64 userdata, s64 cycles_late) { FrameCallback(userdata, cycles_late); });
+ core_timing.ScheduleEvent(MEMORY_FREEZER_TICKS, event);
+}
+
+Freezer::~Freezer() {
+ core_timing.UnscheduleEvent(event, 0);
+}
+
+void Freezer::SetActive(bool active) {
+ if (!this->active.exchange(active)) {
+ FillEntryReads();
+ core_timing.ScheduleEvent(MEMORY_FREEZER_TICKS, event);
+ LOG_DEBUG(Common_Memory, "Memory freezer activated!");
+ } else {
+ LOG_DEBUG(Common_Memory, "Memory freezer deactivated!");
+ }
+}
+
+bool Freezer::IsActive() const {
+ return active.load();
+}
+
+void Freezer::Clear() {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ LOG_DEBUG(Common_Memory, "Clearing all frozen memory values.");
+
+ entries.clear();
+}
+
+u64 Freezer::Freeze(VAddr address, u8 width) {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ const auto current_value = MemoryReadWidth(width, address);
+ entries.push_back({address, width, current_value});
+
+ LOG_DEBUG(Common_Memory,
+ "Freezing memory for address={:016X}, width={:02X}, current_value={:016X}", address,
+ width, current_value);
+
+ return current_value;
+}
+
+void Freezer::Unfreeze(VAddr address) {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ LOG_DEBUG(Common_Memory, "Unfreezing memory for address={:016X}", address);
+
+ entries.erase(
+ std::remove_if(entries.begin(), entries.end(),
+ [&address](const Entry& entry) { return entry.address == address; }),
+ entries.end());
+}
+
+bool Freezer::IsFrozen(VAddr address) {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ return std::find_if(entries.begin(), entries.end(), [&address](const Entry& entry) {
+ return entry.address == address;
+ }) != entries.end();
+}
+
+void Freezer::SetFrozenValue(VAddr address, u64 value) {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ const auto iter = std::find_if(entries.begin(), entries.end(), [&address](const Entry& entry) {
+ return entry.address == address;
+ });
+
+ if (iter == entries.end()) {
+ LOG_ERROR(Common_Memory,
+ "Tried to set freeze value for address={:016X} that is not frozen!", address);
+ return;
+ }
+
+ LOG_DEBUG(Common_Memory,
+ "Manually overridden freeze value for address={:016X}, width={:02X} to value={:016X}",
+ iter->address, iter->width, value);
+ iter->value = value;
+}
+
+std::optional<Freezer::Entry> Freezer::GetEntry(VAddr address) {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ const auto iter = std::find_if(entries.begin(), entries.end(), [&address](const Entry& entry) {
+ return entry.address == address;
+ });
+
+ if (iter == entries.end()) {
+ return std::nullopt;
+ }
+
+ return *iter;
+}
+
+std::vector<Freezer::Entry> Freezer::GetEntries() {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ return entries;
+}
+
+void Freezer::FrameCallback(u64 userdata, s64 cycles_late) {
+ if (!active.load()) {
+ LOG_DEBUG(Common_Memory, "Memory freezer has been deactivated, ending callback events.");
+ return;
+ }
+
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ for (const auto& entry : entries) {
+ LOG_DEBUG(Common_Memory,
+ "Enforcing memory freeze at address={:016X}, value={:016X}, width={:02X}",
+ entry.address, entry.value, entry.width);
+ MemoryWriteWidth(entry.width, entry.address, entry.value);
+ }
+
+ core_timing.ScheduleEvent(MEMORY_FREEZER_TICKS - cycles_late, event);
+}
+
+void Freezer::FillEntryReads() {
+ std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+
+ LOG_DEBUG(Common_Memory, "Updating memory freeze entries to current values.");
+
+ for (auto& entry : entries) {
+ entry.value = MemoryReadWidth(entry.width, entry.address);
+ }
+}
+
+} // namespace Memory
diff --git a/src/core/memory/freezer.h b/src/core/memory/freezer.h
new file mode 100644
index 000000000..3e271793e
--- /dev/null
+++ b/src/core/memory/freezer.h
@@ -0,0 +1,58 @@
+// Copyright 2019 yuzu Emulator Project
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <optional>
+#include <vector>
+#include "common/common_types.h"
+#include "core/core_timing.h"
+
+namespace Core {
+class System;
+} // namespace Core
+
+namespace Memory {
+
+// A class that will effectively freeze memory values.
+class Freezer {
+public:
+ struct Entry {
+ VAddr address;
+ u8 width;
+ u64 value;
+ };
+
+ Freezer(Core::Timing::CoreTiming& core_timing);
+ ~Freezer();
+
+ void SetActive(bool active);
+ bool IsActive() const;
+
+ void Clear();
+
+ u64 Freeze(VAddr address, u8 width);
+ void Unfreeze(VAddr address);
+
+ bool IsFrozen(VAddr address);
+ void SetFrozenValue(VAddr address, u64 value);
+
+ std::optional<Entry> GetEntry(VAddr address);
+
+ std::vector<Entry> GetEntries();
+
+private:
+ void FrameCallback(u64 userdata, s64 cycles_late);
+ void FillEntryReads();
+
+ std::atomic_bool active{false};
+
+ std::recursive_mutex entries_mutex;
+ std::vector<Entry> entries;
+
+ Core::Timing::EventType* event;
+ Core::Timing::CoreTiming& core_timing;
+};
+
+} // namespace Memory
From c9983ad9a71c9462319d27c3791e13fae9d73e46 Mon Sep 17 00:00:00 2001
From: Zach Hilman <zachhilman@gmail.com>
Date: Thu, 30 May 2019 16:57:23 -0400
Subject: [PATCH 2/4] freezer: Add documentation for methods
---
src/core/memory/freezer.cpp | 40 +++++++++++++++++++------------------
src/core/memory/freezer.h | 39 ++++++++++++++++++++++++++----------
2 files changed, 49 insertions(+), 30 deletions(-)
diff --git a/src/core/memory/freezer.cpp b/src/core/memory/freezer.cpp
index 1d0ccf328..6b20e8388 100644
--- a/src/core/memory/freezer.cpp
+++ b/src/core/memory/freezer.cpp
@@ -3,18 +3,20 @@
// Refer to the license.txt file included.
#include "common/assert.h"
+#include "common/logging/log.h"
#include "core/core.h"
+#include "core/core_timing.h"
#include "core/core_timing_util.h"
#include "core/memory.h"
#include "core/memory/freezer.h"
namespace Memory {
-constexpr s64 MEMORY_FREEZER_TICKS = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 60);
-
namespace {
-u64 MemoryReadWidth(u8 width, VAddr addr) {
+constexpr s64 MEMORY_FREEZER_TICKS = static_cast<s64>(Core::Timing::BASE_CLOCK_RATE / 60);
+
+u64 MemoryReadWidth(u32 width, VAddr addr) {
switch (width) {
case 1:
return Read8(addr);
@@ -30,7 +32,7 @@ u64 MemoryReadWidth(u8 width, VAddr addr) {
}
}
-void MemoryWriteWidth(u8 width, VAddr addr, u64 value) {
+void MemoryWriteWidth(u32 width, VAddr addr, u64 value) {
switch (width) {
case 1:
Write8(addr, static_cast<u8>(value));
@@ -73,19 +75,19 @@ void Freezer::SetActive(bool active) {
}
bool Freezer::IsActive() const {
- return active.load();
+ return active.load(std::memory_order_relaxed);
}
void Freezer::Clear() {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+ std::lock_guard lock{entries_mutex};
LOG_DEBUG(Common_Memory, "Clearing all frozen memory values.");
entries.clear();
}
-u64 Freezer::Freeze(VAddr address, u8 width) {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+u64 Freezer::Freeze(VAddr address, u32 width) {
+ std::lock_guard lock{entries_mutex};
const auto current_value = MemoryReadWidth(width, address);
entries.push_back({address, width, current_value});
@@ -98,7 +100,7 @@ u64 Freezer::Freeze(VAddr address, u8 width) {
}
void Freezer::Unfreeze(VAddr address) {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+ std::lock_guard lock{entries_mutex};
LOG_DEBUG(Common_Memory, "Unfreezing memory for address={:016X}", address);
@@ -108,8 +110,8 @@ void Freezer::Unfreeze(VAddr address) {
entries.end());
}
-bool Freezer::IsFrozen(VAddr address) {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+bool Freezer::IsFrozen(VAddr address) const {
+ std::lock_guard lock{entries_mutex};
return std::find_if(entries.begin(), entries.end(), [&address](const Entry& entry) {
return entry.address == address;
@@ -117,7 +119,7 @@ bool Freezer::IsFrozen(VAddr address) {
}
void Freezer::SetFrozenValue(VAddr address, u64 value) {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+ std::lock_guard lock{entries_mutex};
const auto iter = std::find_if(entries.begin(), entries.end(), [&address](const Entry& entry) {
return entry.address == address;
@@ -135,8 +137,8 @@ void Freezer::SetFrozenValue(VAddr address, u64 value) {
iter->value = value;
}
-std::optional<Freezer::Entry> Freezer::GetEntry(VAddr address) {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+std::optional<Freezer::Entry> Freezer::GetEntry(VAddr address) const {
+ std::lock_guard lock{entries_mutex};
const auto iter = std::find_if(entries.begin(), entries.end(), [&address](const Entry& entry) {
return entry.address == address;
@@ -149,19 +151,19 @@ std::optional<Freezer::Entry> Freezer::GetEntry(VAddr address) {
return *iter;
}
-std::vector<Freezer::Entry> Freezer::GetEntries() {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+std::vector<Freezer::Entry> Freezer::GetEntries() const {
+ std::lock_guard lock{entries_mutex};
return entries;
}
void Freezer::FrameCallback(u64 userdata, s64 cycles_late) {
- if (!active.load()) {
+ if (!IsActive()) {
LOG_DEBUG(Common_Memory, "Memory freezer has been deactivated, ending callback events.");
return;
}
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+ std::lock_guard lock{entries_mutex};
for (const auto& entry : entries) {
LOG_DEBUG(Common_Memory,
@@ -174,7 +176,7 @@ void Freezer::FrameCallback(u64 userdata, s64 cycles_late) {
}
void Freezer::FillEntryReads() {
- std::lock_guard<std::recursive_mutex> lock(entries_mutex);
+ std::lock_guard lock{entries_mutex};
LOG_DEBUG(Common_Memory, "Updating memory freeze entries to current values.");
diff --git a/src/core/memory/freezer.h b/src/core/memory/freezer.h
index 3e271793e..b0c610039 100644
--- a/src/core/memory/freezer.h
+++ b/src/core/memory/freezer.h
@@ -4,14 +4,16 @@
#pragma once
+#include <atomic>
+#include <mutex>
#include <optional>
#include <vector>
#include "common/common_types.h"
-#include "core/core_timing.h"
-namespace Core {
-class System;
-} // namespace Core
+namespace Core::Timing {
+class CoreTiming;
+struct EventType;
+} // namespace Core::Timing
namespace Memory {
@@ -20,27 +22,42 @@ class Freezer {
public:
struct Entry {
VAddr address;
- u8 width;
+ u32 width;
u64 value;
};
- Freezer(Core::Timing::CoreTiming& core_timing);
+ explicit Freezer(Core::Timing::CoreTiming& core_timing);
~Freezer();
+ // Enables or disables the entire memory freezer.
void SetActive(bool active);
+
+ // Returns whether or not the freezer is active.
bool IsActive() const;
+ // Removes all entries from the freezer.
void Clear();
- u64 Freeze(VAddr address, u8 width);
+ // Freezes a value to its current memory address. The value the memory is kept at will be the
+ // value that is read during this function. Width can be 1, 2, 4, or 8 (in bytes).
+ u64 Freeze(VAddr address, u32 width);
+
+ // Unfreezes the memory value at address. If the address isn't frozen, this is a no-op.
void Unfreeze(VAddr address);
- bool IsFrozen(VAddr address);
+ // Returns whether or not the address is frozen.
+ bool IsFrozen(VAddr address) const;
+
+ // Sets the value that address should be frozen to. This doesn't change the width set by using
+ // Freeze(). If the value isn't frozen, this will not freeze it and is thus a no-op.
void SetFrozenValue(VAddr address, u64 value);
- std::optional<Entry> GetEntry(VAddr address);
+ // Returns the entry corresponding to the address if the address is frozen, otherwise
+ // std::nullopt.
+ std::optional<Entry> GetEntry(VAddr address) const;
- std::vector<Entry> GetEntries();
+ // Returns all the entries in the freezer, an empty vector means nothing is frozen.
+ std::vector<Entry> GetEntries() const;
private:
void FrameCallback(u64 userdata, s64 cycles_late);
@@ -48,7 +65,7 @@ private:
std::atomic_bool active{false};
- std::recursive_mutex entries_mutex;
+ mutable std::mutex entries_mutex;
std::vector<Entry> entries;
Core::Timing::EventType* event;
From ed82fa3a91fc84f7f906b898d8f71e15fb42c16e Mon Sep 17 00:00:00 2001
From: Zach Hilman <zachhilman@gmail.com>
Date: Fri, 7 Jun 2019 11:11:11 -0400
Subject: [PATCH 3/4] core: Move Freezer class to tools namespace
---
src/core/CMakeLists.txt | 4 ++--
src/core/core.cpp | 4 ++--
src/core/{memory => tools}/freezer.cpp | 22 +++++++++++-----------
src/core/{memory => tools}/freezer.h | 4 ++--
4 files changed, 17 insertions(+), 17 deletions(-)
rename src/core/{memory => tools}/freezer.cpp (91%)
rename src/core/{memory => tools}/freezer.h (98%)
diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index c17528134..59b64407a 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -454,8 +454,6 @@ add_library(core STATIC
loader/nsp.h
loader/xci.cpp
loader/xci.h
- memory/freezer.cpp
- memory/freezer.h
memory.cpp
memory.h
memory_setup.h
@@ -465,6 +463,8 @@ add_library(core STATIC
settings.h
telemetry_session.cpp
telemetry_session.h
+ tools/freezer.cpp
+ tools/freezer.h
)
create_target_directory_groups(core)
diff --git a/src/core/core.cpp b/src/core/core.cpp
index 94ebe0995..48d953442 100644
--- a/src/core/core.cpp
+++ b/src/core/core.cpp
@@ -28,10 +28,10 @@
#include "core/hle/service/service.h"
#include "core/hle/service/sm/sm.h"
#include "core/loader/loader.h"
-#include "core/memory/freezer.h"
#include "core/perf_stats.h"
#include "core/settings.h"
#include "core/telemetry_session.h"
+#include "core/tools/freezer.h"
#include "file_sys/cheat_engine.h"
#include "video_core/debug_utils/debug_utils.h"
#include "video_core/renderer_base.h"
@@ -244,7 +244,7 @@ struct System::Impl {
bool is_powered_on = false;
std::unique_ptr<FileSys::CheatEngine> cheat_engine;
- std::unique_ptr<Memory::Freezer> memory_freezer;
+ std::unique_ptr<Tools::Freezer> memory_freezer;
/// Frontend applets
Service::AM::Applets::AppletManager applet_manager;
diff --git a/src/core/memory/freezer.cpp b/src/core/tools/freezer.cpp
similarity index 91%
rename from src/core/memory/freezer.cpp
rename to src/core/tools/freezer.cpp
index 6b20e8388..17f050068 100644
--- a/src/core/memory/freezer.cpp
+++ b/src/core/tools/freezer.cpp
@@ -8,9 +8,9 @@
#include "core/core_timing.h"
#include "core/core_timing_util.h"
#include "core/memory.h"
-#include "core/memory/freezer.h"
+#include "core/tools/freezer.h"
-namespace Memory {
+namespace Tools {
namespace {
@@ -19,13 +19,13 @@ constexpr s64 MEMORY_FREEZER_TICKS = static_cast<s64>(Core::Timing::BASE_CLOCK_R
u64 MemoryReadWidth(u32 width, VAddr addr) {
switch (width) {
case 1:
- return Read8(addr);
+ return Memory::Read8(addr);
case 2:
- return Read16(addr);
+ return Memory::Read16(addr);
case 4:
- return Read32(addr);
+ return Memory::Read32(addr);
case 8:
- return Read64(addr);
+ return Memory::Read64(addr);
default:
UNREACHABLE();
return 0;
@@ -35,16 +35,16 @@ u64 MemoryReadWidth(u32 width, VAddr addr) {
void MemoryWriteWidth(u32 width, VAddr addr, u64 value) {
switch (width) {
case 1:
- Write8(addr, static_cast<u8>(value));
+ Memory::Write8(addr, static_cast<u8>(value));
break;
case 2:
- Write16(addr, static_cast<u16>(value));
+ Memory::Write16(addr, static_cast<u16>(value));
break;
case 4:
- Write32(addr, static_cast<u32>(value));
+ Memory::Write32(addr, static_cast<u32>(value));
break;
case 8:
- Write64(addr, value);
+ Memory::Write64(addr, value);
break;
default:
UNREACHABLE();
@@ -185,4 +185,4 @@ void Freezer::FillEntryReads() {
}
}
-} // namespace Memory
+} // namespace Tools
diff --git a/src/core/memory/freezer.h b/src/core/tools/freezer.h
similarity index 98%
rename from src/core/memory/freezer.h
rename to src/core/tools/freezer.h
index b0c610039..5edd049c1 100644
--- a/src/core/memory/freezer.h
+++ b/src/core/tools/freezer.h
@@ -15,7 +15,7 @@ class CoreTiming;
struct EventType;
} // namespace Core::Timing
-namespace Memory {
+namespace Tools {
// A class that will effectively freeze memory values.
class Freezer {
@@ -72,4 +72,4 @@ private:
Core::Timing::CoreTiming& core_timing;
};
-} // namespace Memory
+} // namespace Tools
From 4111971cbdae3a4700156a802f8e0c9309a9cf1e Mon Sep 17 00:00:00 2001
From: Zach Hilman <zachhilman@gmail.com>
Date: Mon, 10 Jun 2019 14:11:06 -0400
Subject: [PATCH 4/4] freezer: Update documentation
---
src/core/tools/freezer.h | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
diff --git a/src/core/tools/freezer.h b/src/core/tools/freezer.h
index 5edd049c1..b58de5472 100644
--- a/src/core/tools/freezer.h
+++ b/src/core/tools/freezer.h
@@ -17,7 +17,14 @@ struct EventType;
namespace Tools {
-// A class that will effectively freeze memory values.
+/**
+ * This class allows the user to prevent an application from writing new values to certain memory
+ * locations. This has a variety of uses when attempting to reverse a game.
+ *
+ * One example could be a cheat to prevent Mario from taking damage in SMO. One could freeze the
+ * memory address that the game uses to store Mario's health so when he takes damage (and the game
+ * tries to write the new health value to memory), the value won't change.
+ */
class Freezer {
public:
struct Entry {