HEAERS

src/common/host_memory.cpp

@@ -219,6 +219,11 @@ public:
         }
     }
 
+    bool ClearBackingRegion(size_t physical_offset, size_t length) {
+        // TODO: This does not seem to be possible on Windows.
+        return false;
+    }
+
     void EnableDirectMappedAddress() {
         // TODO
         UNREACHABLE();
@@ -612,6 +617,24 @@ public:
         ASSERT_MSG(ret == 0, "mprotect failed: {}", strerror(errno));
     }
 
+    bool ClearBackingRegion(size_t physical_offset, size_t length) {
+#ifdef __linux__
+        // Only incur syscall cost IF memset would be slower (theshold = 16MiB)
+        // TODO(lizzie): Smarter way to dynamically get this threshold (broadwell != raptor lake) for example
+        if (length >= 2097152UL * 8) {
+            // Set MADV_REMOVE on backing map to destroy it instantly.
+            // This also deletes the area from the backing file.
+            int ret = madvise(backing_base + physical_offset, length, MADV_REMOVE);
+            ASSERT_MSG(ret == 0, "madvise failed: {}", strerror(errno));
+            return true;
+        } else {
+            return false;
+        }
+#else
+        return false;
+#endif
+    }
+
     void EnableDirectMappedAddress() {
         virtual_base = nullptr;
     }
@@ -739,7 +762,9 @@ void HostMemory::Protect(size_t virtual_offset, size_t length, MemoryPermission
 }
 
 void HostMemory::ClearBackingRegion(size_t physical_offset, size_t length, u32 fill_value) {
-    std::memset(backing_base + physical_offset, fill_value, length);
+    if (!impl || fill_value != 0 || !impl->ClearBackingRegion(physical_offset, length)) {
+        std::memset(backing_base + physical_offset, fill_value, length);
+    }
 }
 
 void HostMemory::EnableDirectMappedAddress() {

src/core/hle/service/hle_ipc.cpp

@@ -1,8 +1,12 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
 #include <algorithm>
 #include <array>
+#include <cstring>
 #include <sstream>
 
 #include <boost/range/algorithm_ext/erase.hpp>
@@ -187,7 +191,7 @@ void HLERequestContext::ParseCommandBuffer(u32_le* src_cmdbuf, bool incoming) {
         buffer_w_descriptors.push_back(rp.PopRaw<IPC::BufferDescriptorABW>());
     }
 
-    const auto buffer_c_offset = rp.GetCurrentOffset() + command_header->data_size;
+    buffer_c_offset = rp.GetCurrentOffset() + command_header->data_size;
 
     if (!command_header->IsTipc()) {
         // Padding to align to 16 bytes
@@ -294,7 +298,15 @@ Result HLERequestContext::WriteToOutgoingCommandBuffer() {
     }
 
     // Write the domain objects to the command buffer, these go after the raw untranslated data.
-    // TODO(Subv): This completely ignores C buffers.
+
+    if (buffer_c_offset != 0 && !buffer_c_descriptors.empty()) {
+        constexpr u32 WORDS_PER_DESCRIPTOR = sizeof(IPC::BufferDescriptorC) / sizeof(u32);
+        u32 descriptor_offset = buffer_c_offset;
+        for (const auto& descriptor : buffer_c_descriptors) {
+            std::memcpy(&cmd_buf[descriptor_offset], &descriptor, sizeof(descriptor));
+            descriptor_offset += WORDS_PER_DESCRIPTOR;
+        }
+    }
 
     if (GetManager()->IsDomain()) {
         current_offset = domain_offset - static_cast<u32>(outgoing_domain_objects.size());
@@ -393,10 +405,14 @@ std::size_t HLERequestContext::WriteBuffer(const void* buffer, std::size_t size,
     const bool is_buffer_b{BufferDescriptorB().size() > buffer_index &&
                            BufferDescriptorB()[buffer_index].Size()};
     const std::size_t buffer_size{GetWriteBufferSize(buffer_index)};
+    if (buffer_size == 0) {
+        LOG_WARNING(Core, "WriteBuffer target index {} has zero capacity", buffer_index);
+        return 0;
+    }
     if (size > buffer_size) {
-        LOG_CRITICAL(Core, "size ({:016X}) is greater than buffer_size ({:016X})", size,
-                     buffer_size);
-        size = buffer_size; // TODO(bunnei): This needs to be HW tested
+        LOG_WARNING(Core, "size ({:016X}) is greater than buffer_size ({:016X}); clamping",
+                    size, buffer_size);
+        size = buffer_size;
     }
 
     if (is_buffer_b) {
@@ -418,15 +434,25 @@ std::size_t HLERequestContext::WriteBuffer(const void* buffer, std::size_t size,
 
 std::size_t HLERequestContext::WriteBufferB(const void* buffer, std::size_t size,
                                             std::size_t buffer_index) const {
-    if (buffer_index >= BufferDescriptorB().size() || size == 0) {
+    if (buffer_index >= BufferDescriptorB().size()) {
+        LOG_WARNING(Core, "WriteBufferB invalid buffer index {}", buffer_index);
+        return 0;
+    }
+
+    if (size == 0) {
+        LOG_WARNING(Core, "skip empty buffer write (B)");
         return 0;
     }
 
     const auto buffer_size{BufferDescriptorB()[buffer_index].Size()};
+    if (buffer_size == 0) {
+        LOG_WARNING(Core, "WriteBufferB target index {} has zero capacity", buffer_index);
+        return 0;
+    }
     if (size > buffer_size) {
-        LOG_CRITICAL(Core, "size ({:016X}) is greater than buffer_size ({:016X})", size,
-                     buffer_size);
-        size = buffer_size; // TODO(bunnei): This needs to be HW tested
+        LOG_WARNING(Core, "size ({:016X}) is greater than buffer_size ({:016X}); clamping",
+                    size, buffer_size);
+        size = buffer_size;
     }
 
     memory.WriteBlock(BufferDescriptorB()[buffer_index].Address(), buffer, size);
@@ -435,15 +461,25 @@ std::size_t HLERequestContext::WriteBufferB(const void* buffer, std::size_t size
 
 std::size_t HLERequestContext::WriteBufferC(const void* buffer, std::size_t size,
                                             std::size_t buffer_index) const {
-    if (buffer_index >= BufferDescriptorC().size() || size == 0) {
+    if (buffer_index >= BufferDescriptorC().size()) {
+        LOG_WARNING(Core, "WriteBufferC invalid buffer index {}", buffer_index);
+        return 0;
+    }
+
+    if (size == 0) {
+        LOG_WARNING(Core, "skip empty buffer write (C)");
         return 0;
     }
 
     const auto buffer_size{BufferDescriptorC()[buffer_index].Size()};
+    if (buffer_size == 0) {
+        LOG_WARNING(Core, "WriteBufferC target index {} has zero capacity", buffer_index);
+        return 0;
+    }
     if (size > buffer_size) {
-        LOG_CRITICAL(Core, "size ({:016X}) is greater than buffer_size ({:016X})", size,
-                     buffer_size);
-        size = buffer_size; // TODO(bunnei): This needs to be HW tested
+        LOG_WARNING(Core, "size ({:016X}) is greater than buffer_size ({:016X}); clamping",
+                    size, buffer_size);
+        size = buffer_size;
     }
 
     memory.WriteBlock(BufferDescriptorC()[buffer_index].Address(), buffer, size);
@@ -473,12 +509,20 @@ std::size_t HLERequestContext::GetWriteBufferSize(std::size_t buffer_index) cons
         ASSERT_OR_EXECUTE_MSG(
             BufferDescriptorB().size() > buffer_index, { return 0; },
             "BufferDescriptorB invalid buffer_index {}", buffer_index);
-        return BufferDescriptorB()[buffer_index].Size();
+        const auto size = BufferDescriptorB()[buffer_index].Size();
+        if (size == 0) {
+            LOG_WARNING(Core, "BufferDescriptorB index {} has zero size", buffer_index);
+        }
+        return size;
     } else {
         ASSERT_OR_EXECUTE_MSG(
             BufferDescriptorC().size() > buffer_index, { return 0; },
             "BufferDescriptorC invalid buffer_index {}", buffer_index);
-        return BufferDescriptorC()[buffer_index].Size();
+        const auto size = BufferDescriptorC()[buffer_index].Size();
+        if (size == 0) {
+            LOG_WARNING(Core, "BufferDescriptorC index {} has zero size", buffer_index);
+        }
+        return size;
     }
     return 0;
 }

src/core/hle/service/hle_ipc.h

@@ -1,3 +1,6 @@
+// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-License-Identifier: GPL-3.0-or-later
+
 // SPDX-FileCopyrightText: Copyright 2018 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
@@ -422,6 +425,7 @@ private:
     u32 data_payload_offset{};
     u32 handles_offset{};
     u32 domain_offset{};
+    u32 buffer_c_offset{};
 
     std::weak_ptr<SessionRequestManager> manager{};
     bool is_deferred{false};