Merge pull request #9078 from liamwhite/session-request

kernel: Session request cleanup

src/core/CMakeLists.txt

@@ -243,6 +243,8 @@ add_library(core STATIC
     hle/kernel/k_server_session.h
     hle/kernel/k_session.cpp
     hle/kernel/k_session.h
+    hle/kernel/k_session_request.cpp
+    hle/kernel/k_session_request.h
     hle/kernel/k_shared_memory.cpp
     hle/kernel/k_shared_memory.h
     hle/kernel/k_shared_memory_info.h

src/core/hle/ipc_helpers.h

@@ -86,13 +86,13 @@ public:
         u32 num_domain_objects{};
         const bool always_move_handles{
             (static_cast<u32>(flags) & static_cast<u32>(Flags::AlwaysMoveHandles)) != 0};
-        if (!ctx.Session()->IsDomain() || always_move_handles) {
+        if (!ctx.Session()->GetSessionRequestManager()->IsDomain() || always_move_handles) {
             num_handles_to_move = num_objects_to_move;
         } else {
             num_domain_objects = num_objects_to_move;
         }
 
-        if (ctx.Session()->IsDomain()) {
+        if (ctx.Session()->GetSessionRequestManager()->IsDomain()) {
             raw_data_size +=
                 static_cast<u32>(sizeof(DomainMessageHeader) / sizeof(u32) + num_domain_objects);
             ctx.write_size += num_domain_objects;
@@ -125,7 +125,8 @@ public:
         if (!ctx.IsTipc()) {
             AlignWithPadding();
 
-            if (ctx.Session()->IsDomain() && ctx.HasDomainMessageHeader()) {
+            if (ctx.Session()->GetSessionRequestManager()->IsDomain() &&
+                ctx.HasDomainMessageHeader()) {
                 IPC::DomainMessageHeader domain_header{};
                 domain_header.num_objects = num_domain_objects;
                 PushRaw(domain_header);
@@ -145,7 +146,7 @@ public:
 
     template <class T>
     void PushIpcInterface(std::shared_ptr<T> iface) {
-        if (context->Session()->IsDomain()) {
+        if (context->Session()->GetSessionRequestManager()->IsDomain()) {
             context->AddDomainObject(std::move(iface));
         } else {
             kernel.CurrentProcess()->GetResourceLimit()->Reserve(
@@ -386,7 +387,7 @@ public:
 
     template <class T>
     std::weak_ptr<T> PopIpcInterface() {
-        ASSERT(context->Session()->IsDomain());
+        ASSERT(context->Session()->GetSessionRequestManager()->IsDomain());
         ASSERT(context->GetDomainMessageHeader().input_object_count > 0);
         return context->GetDomainHandler<T>(Pop<u32>() - 1);
     }

src/core/hle/kernel/hle_ipc.cpp

@@ -19,6 +19,7 @@
 #include "core/hle/kernel/k_server_session.h"
 #include "core/hle/kernel/k_thread.h"
 #include "core/hle/kernel/kernel.h"
+#include "core/hle/kernel/service_thread.h"
 #include "core/memory.h"
 
 namespace Kernel {
@@ -56,16 +57,103 @@ bool SessionRequestManager::HasSessionRequestHandler(const HLERequestContext& co
     }
 }
 
+Result SessionRequestManager::CompleteSyncRequest(KServerSession* server_session,
+                                                  HLERequestContext& context) {
+    Result result = ResultSuccess;
+
+    // If the session has been converted to a domain, handle the domain request
+    if (this->HasSessionRequestHandler(context)) {
+        if (IsDomain() && context.HasDomainMessageHeader()) {
+            result = HandleDomainSyncRequest(server_session, context);
+            // If there is no domain header, the regular session handler is used
+        } else if (this->HasSessionHandler()) {
+            // If this manager has an associated HLE handler, forward the request to it.
+            result = this->SessionHandler().HandleSyncRequest(*server_session, context);
+        }
+    } else {
+        ASSERT_MSG(false, "Session handler is invalid, stubbing response!");
+        IPC::ResponseBuilder rb(context, 2);
+        rb.Push(ResultSuccess);
+    }
+
+    if (convert_to_domain) {
+        ASSERT_MSG(!IsDomain(), "ServerSession is already a domain instance.");
+        this->ConvertToDomain();
+        convert_to_domain = false;
+    }
+
+    return result;
+}
+
+Result SessionRequestManager::HandleDomainSyncRequest(KServerSession* server_session,
+                                                      HLERequestContext& context) {
+    if (!context.HasDomainMessageHeader()) {
+        return ResultSuccess;
+    }
+
+    // Set domain handlers in HLE context, used for domain objects (IPC interfaces) as inputs
+    context.SetSessionRequestManager(server_session->GetSessionRequestManager());
+
+    // If there is a DomainMessageHeader, then this is CommandType "Request"
+    const auto& domain_message_header = context.GetDomainMessageHeader();
+    const u32 object_id{domain_message_header.object_id};
+    switch (domain_message_header.command) {
+    case IPC::DomainMessageHeader::CommandType::SendMessage:
+        if (object_id > this->DomainHandlerCount()) {
+            LOG_CRITICAL(IPC,
+                         "object_id {} is too big! This probably means a recent service call "
+                         "needed to return a new interface!",
+                         object_id);
+            ASSERT(false);
+            return ResultSuccess; // Ignore error if asserts are off
+        }
+        if (auto strong_ptr = this->DomainHandler(object_id - 1).lock()) {
+            return strong_ptr->HandleSyncRequest(*server_session, context);
+        } else {
+            ASSERT(false);
+            return ResultSuccess;
+        }
+
+    case IPC::DomainMessageHeader::CommandType::CloseVirtualHandle: {
+        LOG_DEBUG(IPC, "CloseVirtualHandle, object_id=0x{:08X}", object_id);
+
+        this->CloseDomainHandler(object_id - 1);
+
+        IPC::ResponseBuilder rb{context, 2};
+        rb.Push(ResultSuccess);
+        return ResultSuccess;
+    }
+    }
+
+    LOG_CRITICAL(IPC, "Unknown domain command={}", domain_message_header.command.Value());
+    ASSERT(false);
+    return ResultSuccess;
+}
+
+Result SessionRequestManager::QueueSyncRequest(KSession* parent,
+                                               std::shared_ptr<HLERequestContext>&& context) {
+    // Ensure we have a session request handler
+    if (this->HasSessionRequestHandler(*context)) {
+        if (auto strong_ptr = this->GetServiceThread().lock()) {
+            strong_ptr->QueueSyncRequest(*parent, std::move(context));
+        } else {
+            ASSERT_MSG(false, "strong_ptr is nullptr!");
+        }
+    } else {
+        ASSERT_MSG(false, "handler is invalid!");
+    }
+
+    return ResultSuccess;
+}
+
 void SessionRequestHandler::ClientConnected(KServerSession* session) {
-    session->ClientConnected(shared_from_this());
+    session->GetSessionRequestManager()->SetSessionHandler(shared_from_this());
 
     // Ensure our server session is tracked globally.
     kernel.RegisterServerObject(session);
 }
 
-void SessionRequestHandler::ClientDisconnected(KServerSession* session) {
-    session->ClientDisconnected();
-}
+void SessionRequestHandler::ClientDisconnected(KServerSession* session) {}
 
 HLERequestContext::HLERequestContext(KernelCore& kernel_, Core::Memory::Memory& memory_,
                                      KServerSession* server_session_, KThread* thread_)
@@ -126,7 +214,7 @@ void HLERequestContext::ParseCommandBuffer(const KHandleTable& handle_table, u32
         // Padding to align to 16 bytes
         rp.AlignWithPadding();
 
-        if (Session()->IsDomain() &&
+        if (Session()->GetSessionRequestManager()->IsDomain() &&
             ((command_header->type == IPC::CommandType::Request ||
               command_header->type == IPC::CommandType::RequestWithContext) ||
              !incoming)) {
@@ -135,7 +223,7 @@ void HLERequestContext::ParseCommandBuffer(const KHandleTable& handle_table, u32
             if (incoming || domain_message_header) {
                 domain_message_header = rp.PopRaw<IPC::DomainMessageHeader>();
             } else {
-                if (Session()->IsDomain()) {
+                if (Session()->GetSessionRequestManager()->IsDomain()) {
                     LOG_WARNING(IPC, "Domain request has no DomainMessageHeader!");
                 }
             }
@@ -228,12 +316,12 @@ Result HLERequestContext::WriteToOutgoingCommandBuffer(KThread& requesting_threa
     // Write the domain objects to the command buffer, these go after the raw untranslated data.
     // TODO(Subv): This completely ignores C buffers.
 
-    if (Session()->IsDomain()) {
+    if (server_session->GetSessionRequestManager()->IsDomain()) {
         current_offset = domain_offset - static_cast<u32>(outgoing_domain_objects.size());
-        for (const auto& object : outgoing_domain_objects) {
-            server_session->AppendDomainHandler(object);
-            cmd_buf[current_offset++] =
-                static_cast<u32_le>(server_session->NumDomainRequestHandlers());
+        for (auto& object : outgoing_domain_objects) {
+            server_session->GetSessionRequestManager()->AppendDomainHandler(std::move(object));
+            cmd_buf[current_offset++] = static_cast<u32_le>(
+                server_session->GetSessionRequestManager()->DomainHandlerCount());
         }
     }
 

src/core/hle/kernel/hle_ipc.h

@@ -121,6 +121,10 @@ public:
         is_domain = true;
     }
 
+    void ConvertToDomainOnRequestEnd() {
+        convert_to_domain = true;
+    }
+
     std::size_t DomainHandlerCount() const {
         return domain_handlers.size();
     }
@@ -164,7 +168,12 @@ public:
 
     bool HasSessionRequestHandler(const HLERequestContext& context) const;
 
+    Result HandleDomainSyncRequest(KServerSession* server_session, HLERequestContext& context);
+    Result CompleteSyncRequest(KServerSession* server_session, HLERequestContext& context);
+    Result QueueSyncRequest(KSession* parent, std::shared_ptr<HLERequestContext>&& context);
+
 private:
+    bool convert_to_domain{};
     bool is_domain{};
     SessionRequestHandlerPtr session_handler;
     std::vector<SessionRequestHandlerPtr> domain_handlers;

src/core/hle/kernel/init/init_slab_setup.cpp

@@ -18,6 +18,7 @@
 #include "core/hle/kernel/k_process.h"
 #include "core/hle/kernel/k_resource_limit.h"
 #include "core/hle/kernel/k_session.h"
+#include "core/hle/kernel/k_session_request.h"
 #include "core/hle/kernel/k_shared_memory.h"
 #include "core/hle/kernel/k_shared_memory_info.h"
 #include "core/hle/kernel/k_system_control.h"
@@ -34,6 +35,7 @@ namespace Kernel::Init {
     HANDLER(KThread, (SLAB_COUNT(KThread)), ##__VA_ARGS__)                                         \
     HANDLER(KEvent, (SLAB_COUNT(KEvent)), ##__VA_ARGS__)                                           \
     HANDLER(KPort, (SLAB_COUNT(KPort)), ##__VA_ARGS__)                                             \
+    HANDLER(KSessionRequest, (SLAB_COUNT(KSession) * 2), ##__VA_ARGS__)                            \
     HANDLER(KSharedMemory, (SLAB_COUNT(KSharedMemory)), ##__VA_ARGS__)                             \
     HANDLER(KSharedMemoryInfo, (SLAB_COUNT(KSharedMemory) * 8), ##__VA_ARGS__)                     \
     HANDLER(KTransferMemory, (SLAB_COUNT(KTransferMemory)), ##__VA_ARGS__)                         \

src/core/hle/kernel/k_client_session.cpp

@@ -1,6 +1,7 @@
 // SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
 // SPDX-License-Identifier: GPL-2.0-or-later
 
+#include "common/scope_exit.h"
 #include "core/hle/kernel/hle_ipc.h"
 #include "core/hle/kernel/k_client_session.h"
 #include "core/hle/kernel/k_server_session.h"
@@ -10,6 +11,8 @@
 
 namespace Kernel {
 
+static constexpr u32 MessageBufferSize = 0x100;
+
 KClientSession::KClientSession(KernelCore& kernel_)
     : KAutoObjectWithSlabHeapAndContainer{kernel_} {}
 KClientSession::~KClientSession() = default;
@@ -22,8 +25,16 @@ void KClientSession::Destroy() {
 void KClientSession::OnServerClosed() {}
 
 Result KClientSession::SendSyncRequest() {
-    // Signal the server session that new data is available
-    return parent->GetServerSession().OnRequest();
+    // Create a session request.
+    KSessionRequest* request = KSessionRequest::Create(kernel);
+    R_UNLESS(request != nullptr, ResultOutOfResource);
+    SCOPE_EXIT({ request->Close(); });
+
+    // Initialize the request.
+    request->Initialize(nullptr, GetCurrentThread(kernel).GetTLSAddress(), MessageBufferSize);
+
+    // Send the request.
+    return parent->GetServerSession().OnRequest(request);
 }
 
 } // namespace Kernel

src/core/hle/kernel/k_linked_list.h

@@ -16,6 +16,7 @@ class KLinkedListNode : public boost::intrusive::list_base_hook<>,
                         public KSlabAllocated<KLinkedListNode> {
 
 public:
+    explicit KLinkedListNode(KernelCore&) {}
     KLinkedListNode() = default;
 
     void Initialize(void* it) {

src/core/hle/kernel/k_page_buffer.h

@@ -13,6 +13,7 @@ namespace Kernel {
 
 class KPageBuffer final : public KSlabAllocated<KPageBuffer> {
 public:
+    explicit KPageBuffer(KernelCore&) {}
     KPageBuffer() = default;
 
     static KPageBuffer* FromPhysicalAddress(Core::System& system, PAddr phys_addr);

src/core/hle/kernel/k_server_session.cpp

@@ -22,15 +22,12 @@
 #include "core/hle/kernel/k_thread.h"
 #include "core/hle/kernel/k_thread_queue.h"
 #include "core/hle/kernel/kernel.h"
-#include "core/hle/kernel/service_thread.h"
 #include "core/memory.h"
 
 namespace Kernel {
 
 using ThreadQueueImplForKServerSessionRequest = KThreadQueue;
 
-static constexpr u32 MessageBufferSize = 0x100;
-
 KServerSession::KServerSession(KernelCore& kernel_)
     : KSynchronizationObject{kernel_}, m_lock{kernel_} {}
 
@@ -73,59 +70,7 @@ bool KServerSession::IsSignaled() const {
     }
 
     // Otherwise, we're signaled if we have a request and aren't handling one.
-    return !m_thread_request_list.empty() && m_current_thread_request == nullptr;
-}
-
-void KServerSession::AppendDomainHandler(SessionRequestHandlerPtr handler) {
-    manager->AppendDomainHandler(std::move(handler));
-}
-
-std::size_t KServerSession::NumDomainRequestHandlers() const {
-    return manager->DomainHandlerCount();
-}
-
-Result KServerSession::HandleDomainSyncRequest(Kernel::HLERequestContext& context) {
-    if (!context.HasDomainMessageHeader()) {
-        return ResultSuccess;
-    }
-
-    // Set domain handlers in HLE context, used for domain objects (IPC interfaces) as inputs
-    context.SetSessionRequestManager(manager);
-
-    // If there is a DomainMessageHeader, then this is CommandType "Request"
-    const auto& domain_message_header = context.GetDomainMessageHeader();
-    const u32 object_id{domain_message_header.object_id};
-    switch (domain_message_header.command) {
-    case IPC::DomainMessageHeader::CommandType::SendMessage:
-        if (object_id > manager->DomainHandlerCount()) {
-            LOG_CRITICAL(IPC,
-                         "object_id {} is too big! This probably means a recent service call "
-                         "to {} needed to return a new interface!",
-                         object_id, name);
-            ASSERT(false);
-            return ResultSuccess; // Ignore error if asserts are off
-        }
-        if (auto strong_ptr = manager->DomainHandler(object_id - 1).lock()) {
-            return strong_ptr->HandleSyncRequest(*this, context);
-        } else {
-            ASSERT(false);
-            return ResultSuccess;
-        }
-
-    case IPC::DomainMessageHeader::CommandType::CloseVirtualHandle: {
-        LOG_DEBUG(IPC, "CloseVirtualHandle, object_id=0x{:08X}", object_id);
-
-        manager->CloseDomainHandler(object_id - 1);
-
-        IPC::ResponseBuilder rb{context, 2};
-        rb.Push(ResultSuccess);
-        return ResultSuccess;
-    }
-    }
-
-    LOG_CRITICAL(IPC, "Unknown domain command={}", domain_message_header.command.Value());
-    ASSERT(false);
-    return ResultSuccess;
+    return !m_request_list.empty() && m_current_request == nullptr;
 }
 
 Result KServerSession::QueueSyncRequest(KThread* thread, Core::Memory::Memory& memory) {
@@ -134,43 +79,11 @@ Result KServerSession::QueueSyncRequest(KThread* thread, Core::Memory::Memory& m
 
     context->PopulateFromIncomingCommandBuffer(kernel.CurrentProcess()->GetHandleTable(), cmd_buf);
 
-    // Ensure we have a session request handler
-    if (manager->HasSessionRequestHandler(*context)) {
-        if (auto strong_ptr = manager->GetServiceThread().lock()) {
-            strong_ptr->QueueSyncRequest(*parent, std::move(context));
-        } else {
-            ASSERT_MSG(false, "strong_ptr is nullptr!");
-        }
-    } else {
-        ASSERT_MSG(false, "handler is invalid!");
-    }
-
-    return ResultSuccess;
+    return manager->QueueSyncRequest(parent, std::move(context));
 }
 
 Result KServerSession::CompleteSyncRequest(HLERequestContext& context) {
-    Result result = ResultSuccess;
-
-    // If the session has been converted to a domain, handle the domain request
-    if (manager->HasSessionRequestHandler(context)) {
-        if (IsDomain() && context.HasDomainMessageHeader()) {
-            result = HandleDomainSyncRequest(context);
-            // If there is no domain header, the regular session handler is used
-        } else if (manager->HasSessionHandler()) {
-            // If this ServerSession has an associated HLE handler, forward the request to it.
-            result = manager->SessionHandler().HandleSyncRequest(*this, context);
-        }
-    } else {
-        ASSERT_MSG(false, "Session handler is invalid, stubbing response!");
-        IPC::ResponseBuilder rb(context, 2);
-        rb.Push(ResultSuccess);
-    }
-
-    if (convert_to_domain) {
-        ASSERT_MSG(!IsDomain(), "ServerSession is already a domain instance.");
-        manager->ConvertToDomain();
-        convert_to_domain = false;
-    }
+    Result result = manager->CompleteSyncRequest(this, context);
 
     // The calling thread is waiting for this request to complete, so wake it up.
     context.GetThread().EndWait(result);
@@ -178,7 +91,7 @@ Result KServerSession::CompleteSyncRequest(HLERequestContext& context) {
     return result;
 }
 
-Result KServerSession::OnRequest() {
+Result KServerSession::OnRequest(KSessionRequest* request) {
     // Create the wait queue.
     ThreadQueueImplForKServerSessionRequest wait_queue{kernel};
 
@@ -198,14 +111,13 @@ Result KServerSession::OnRequest() {
             this->QueueSyncRequest(GetCurrentThreadPointer(kernel), memory);
         } else {
             // Non-HLE request.
-            auto* thread{GetCurrentThreadPointer(kernel)};
 
             // Get whether we're empty.
-            const bool was_empty = m_thread_request_list.empty();
+            const bool was_empty = m_request_list.empty();
 
-            // Add the thread to the list.
-            thread->Open();
-            m_thread_request_list.push_back(thread);
+            // Add the request to the list.
+            request->Open();
+            m_request_list.push_back(*request);
 
             // If we were empty, signal.
             if (was_empty) {
@@ -213,6 +125,9 @@ Result KServerSession::OnRequest() {
             }
         }
 
+        // If we have a request event, this is asynchronous, and we don't need to wait.
+        R_SUCCEED_IF(request->GetEvent() != nullptr);
+
         // This is a synchronous request, so we should wait for our request to complete.
         GetCurrentThread(kernel).SetWaitReasonForDebugging(ThreadWaitReasonForDebugging::IPC);
         GetCurrentThread(kernel).BeginWait(&wait_queue);
@@ -223,32 +138,32 @@ Result KServerSession::OnRequest() {
 
 Result KServerSession::SendReply() {
     // Lock the session.
-    KScopedLightLock lk(m_lock);
+    KScopedLightLock lk{m_lock};
 
     // Get the request.
-    KThread* client_thread;
+    KSessionRequest* request;
     {
         KScopedSchedulerLock sl{kernel};
 
         // Get the current request.
-        client_thread = m_current_thread_request;
-        R_UNLESS(client_thread != nullptr, ResultInvalidState);
+        request = m_current_request;
+        R_UNLESS(request != nullptr, ResultInvalidState);
 
         // Clear the current request, since we're processing it.
-        m_current_thread_request = nullptr;
-        if (!m_thread_request_list.empty()) {
+        m_current_request = nullptr;
+        if (!m_request_list.empty()) {
             this->NotifyAvailable();
         }
     }
 
     // Close reference to the request once we're done processing it.
-    SCOPE_EXIT({ client_thread->Close(); });
+    SCOPE_EXIT({ request->Close(); });
 
     // Extract relevant information from the request.
-    // const uintptr_t client_message  = request->GetAddress();
-    // const size_t client_buffer_size = request->GetSize();
-    // KThread *client_thread          = request->GetThread();
-    // KEvent *event                   = request->GetEvent();
+    const uintptr_t client_message = request->GetAddress();
+    const size_t client_buffer_size = request->GetSize();
+    KThread* client_thread = request->GetThread();
+    KEvent* event = request->GetEvent();
 
     // Check whether we're closed.
     const bool closed = (client_thread == nullptr || parent->IsClientClosed());
@@ -261,8 +176,8 @@ Result KServerSession::SendReply() {
         UNIMPLEMENTED_IF(server_thread->GetOwnerProcess() != client_thread->GetOwnerProcess());
 
         auto* src_msg_buffer = memory.GetPointer(server_thread->GetTLSAddress());
-        auto* dst_msg_buffer = memory.GetPointer(client_thread->GetTLSAddress());
-        std::memcpy(dst_msg_buffer, src_msg_buffer, MessageBufferSize);
+        auto* dst_msg_buffer = memory.GetPointer(client_message);
+        std::memcpy(dst_msg_buffer, src_msg_buffer, client_buffer_size);
     } else {
         result = ResultSessionClosed;
     }
@@ -278,11 +193,30 @@ Result KServerSession::SendReply() {
 
     // If there's a client thread, update it.
     if (client_thread != nullptr) {
-        // End the client thread's wait.
-        KScopedSchedulerLock sl{kernel};
+        if (event != nullptr) {
+            // // Get the client process/page table.
+            // KProcess *client_process             = client_thread->GetOwnerProcess();
+            // KPageTable *client_page_table        = &client_process->PageTable();
+
+            // // If we need to, reply with an async error.
+            // if (R_FAILED(client_result)) {
+            //     ReplyAsyncError(client_process, client_message, client_buffer_size,
+            //     client_result);
+            // }
+
+            // // Unlock the client buffer.
+            // // NOTE: Nintendo does not check the result of this.
+            // client_page_table->UnlockForIpcUserBuffer(client_message, client_buffer_size);
+
+            // Signal the event.
+            event->Signal();
+        } else {
+            // End the client thread's wait.
+            KScopedSchedulerLock sl{kernel};
 
-        if (!client_thread->IsTerminationRequested()) {
-            client_thread->EndWait(client_result);
+            if (!client_thread->IsTerminationRequested()) {
+                client_thread->EndWait(client_result);
+            }
         }
     }
 
@@ -291,10 +225,10 @@ Result KServerSession::SendReply() {
 
 Result KServerSession::ReceiveRequest() {
     // Lock the session.
-    KScopedLightLock lk(m_lock);
+    KScopedLightLock lk{m_lock};
 
     // Get the request and client thread.
-    // KSessionRequest *request;
+    KSessionRequest* request;
     KThread* client_thread;
 
     {
@@ -304,35 +238,41 @@ Result KServerSession::ReceiveRequest() {
         R_UNLESS(!parent->IsClientClosed(), ResultSessionClosed);
 
         // Ensure we aren't already servicing a request.
-        R_UNLESS(m_current_thread_request == nullptr, ResultNotFound);
+        R_UNLESS(m_current_request == nullptr, ResultNotFound);
 
         // Ensure we have a request to service.
-        R_UNLESS(!m_thread_request_list.empty(), ResultNotFound);
+        R_UNLESS(!m_request_list.empty(), ResultNotFound);
 
         // Pop the first request from the list.
-        client_thread = m_thread_request_list.front();
-        m_thread_request_list.pop_front();
+        request = &m_request_list.front();
+        m_request_list.pop_front();
 
         // Get the thread for the request.
+        client_thread = request->GetThread();
         R_UNLESS(client_thread != nullptr, ResultSessionClosed);
 
         // Open the client thread.
         client_thread->Open();
     }
 
-    // SCOPE_EXIT({ client_thread->Close(); });
+    SCOPE_EXIT({ client_thread->Close(); });
 
     // Set the request as our current.
-    m_current_thread_request = client_thread;
+    m_current_request = request;
+
+    // Get the client address.
+    uintptr_t client_message = request->GetAddress();
+    size_t client_buffer_size = request->GetSize();
+    // bool recv_list_broken = false;
 
     // Receive the message.
     Core::Memory::Memory& memory{kernel.System().Memory()};
     KThread* server_thread{GetCurrentThreadPointer(kernel)};
     UNIMPLEMENTED_IF(server_thread->GetOwnerProcess() != client_thread->GetOwnerProcess());
 
-    auto* src_msg_buffer = memory.GetPointer(client_thread->GetTLSAddress());
+    auto* src_msg_buffer = memory.GetPointer(client_message);
     auto* dst_msg_buffer = memory.GetPointer(server_thread->GetTLSAddress());
-    std::memcpy(dst_msg_buffer, src_msg_buffer, MessageBufferSize);
+    std::memcpy(dst_msg_buffer, src_msg_buffer, client_buffer_size);
 
     // We succeeded.
     return ResultSuccess;
@@ -344,35 +284,34 @@ void KServerSession::CleanupRequests() {
     // Clean up any pending requests.
     while (true) {
         // Get the next request.
-        // KSessionRequest *request = nullptr;
-        KThread* client_thread = nullptr;
+        KSessionRequest* request = nullptr;
         {
             KScopedSchedulerLock sl{kernel};
 
-            if (m_current_thread_request) {
+            if (m_current_request) {
                 // Choose the current request if we have one.
-                client_thread = m_current_thread_request;
-                m_current_thread_request = nullptr;
-            } else if (!m_thread_request_list.empty()) {
+                request = m_current_request;
+                m_current_request = nullptr;
+            } else if (!m_request_list.empty()) {
                 // Pop the request from the front of the list.
-                client_thread = m_thread_request_list.front();
-                m_thread_request_list.pop_front();
+                request = &m_request_list.front();
+                m_request_list.pop_front();
             }
         }
 
         // If there's no request, we're done.
-        if (client_thread == nullptr) {
+        if (request == nullptr) {
             break;
         }
 
         // Close a reference to the request once it's cleaned up.
-        SCOPE_EXIT({ client_thread->Close(); });
+        SCOPE_EXIT({ request->Close(); });
 
         // Extract relevant information from the request.
         // const uintptr_t client_message  = request->GetAddress();
         // const size_t client_buffer_size = request->GetSize();
-        // KThread *client_thread          = request->GetThread();
-        // KEvent *event                   = request->GetEvent();
+        KThread* client_thread = request->GetThread();
+        KEvent* event = request->GetEvent();
 
         // KProcess *server_process             = request->GetServerProcess();
         // KProcess *client_process             = (client_thread != nullptr) ?
@@ -385,11 +324,24 @@ void KServerSession::CleanupRequests() {
 
         // If there's a client thread, update it.
         if (client_thread != nullptr) {
-            // End the client thread's wait.
-            KScopedSchedulerLock sl{kernel};
-
-            if (!client_thread->IsTerminationRequested()) {
-                client_thread->EndWait(ResultSessionClosed);
+            if (event != nullptr) {
+                // // We need to reply async.
+                // ReplyAsyncError(client_process, client_message, client_buffer_size,
+                //                 (R_SUCCEEDED(result) ? ResultSessionClosed : result));
+
+                // // Unlock the client buffer.
+                // NOTE: Nintendo does not check the result of this.
+                // client_page_table->UnlockForIpcUserBuffer(client_message, client_buffer_size);
+
+                // Signal the event.
+                event->Signal();
+            } else {
+                // End the client thread's wait.
+                KScopedSchedulerLock sl{kernel};
+
+                if (!client_thread->IsTerminationRequested()) {
+                    client_thread->EndWait(ResultSessionClosed);
+                }
             }
         }
     }

src/core/hle/kernel/k_server_session.h

@@ -12,6 +12,7 @@
 
 #include "core/hle/kernel/hle_ipc.h"
 #include "core/hle/kernel/k_light_lock.h"
+#include "core/hle/kernel/k_session_request.h"
 #include "core/hle/kernel/k_synchronization_object.h"
 #include "core/hle/result.h"
 
@@ -57,44 +58,15 @@ public:
     }
 
     bool IsSignaled() const override;
-
     void OnClientClosed();
 
-    void ClientConnected(SessionRequestHandlerPtr handler) {
-        if (manager) {
-            manager->SetSessionHandler(std::move(handler));
-        }
-    }
-
-    void ClientDisconnected() {
-        manager = nullptr;
-    }
-
-    /// Adds a new domain request handler to the collection of request handlers within
-    /// this ServerSession instance.
-    void AppendDomainHandler(SessionRequestHandlerPtr handler);
-
-    /// Retrieves the total number of domain request handlers that have been
-    /// appended to this ServerSession instance.
-    std::size_t NumDomainRequestHandlers() const;
-
-    /// Returns true if the session has been converted to a domain, otherwise False
-    bool IsDomain() const {
-        return manager && manager->IsDomain();
-    }
-
-    /// Converts the session to a domain at the end of the current command
-    void ConvertToDomain() {
-        convert_to_domain = true;
-    }
-
     /// Gets the session request manager, which forwards requests to the underlying service
     std::shared_ptr<SessionRequestManager>& GetSessionRequestManager() {
         return manager;
     }
 
     /// TODO: flesh these out to match the real kernel
-    Result OnRequest();
+    Result OnRequest(KSessionRequest* request);
     Result SendReply();
     Result ReceiveRequest();
 
@@ -108,10 +80,6 @@ private:
     /// Completes a sync request from the emulated application.
     Result CompleteSyncRequest(HLERequestContext& context);
 
-    /// Handles a SyncRequest to a domain, forwarding the request to the proper object or closing an
-    /// object handle.
-    Result HandleDomainSyncRequest(Kernel::HLERequestContext& context);
-
     /// This session's HLE request handlers; if nullptr, this is not an HLE server
     std::shared_ptr<SessionRequestManager> manager;
 
@@ -122,9 +90,8 @@ private:
     KSession* parent{};
 
     /// List of threads which are pending a reply.
-    /// FIXME: KSessionRequest
-    std::list<KThread*> m_thread_request_list;
-    KThread* m_current_thread_request{};
+    boost::intrusive::list<KSessionRequest> m_request_list;
+    KSessionRequest* m_current_request;
 
     KLightLock m_lock;
 };

src/core/hle/kernel/k_session_request.cpp

@@ -0,0 +1,61 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#include "core/hle/kernel/k_page_buffer.h"
+#include "core/hle/kernel/k_session_request.h"
+
+namespace Kernel {
+
+Result KSessionRequest::SessionMappings::PushMap(VAddr client, VAddr server, size_t size,
+                                                 KMemoryState state, size_t index) {
+    // At most 15 buffers of each type (4-bit descriptor counts).
+    ASSERT(index < ((1ul << 4) - 1) * 3);
+
+    // Get the mapping.
+    Mapping* mapping;
+    if (index < NumStaticMappings) {
+        mapping = &m_static_mappings[index];
+    } else {
+        // Allocate a page for the extra mappings.
+        if (m_mappings == nullptr) {
+            KPageBuffer* page_buffer = KPageBuffer::Allocate(kernel);
+            R_UNLESS(page_buffer != nullptr, ResultOutOfMemory);
+
+            m_mappings = reinterpret_cast<Mapping*>(page_buffer);
+        }
+
+        mapping = &m_mappings[index - NumStaticMappings];
+    }
+
+    // Set the mapping.
+    mapping->Set(client, server, size, state);
+
+    return ResultSuccess;
+}
+
+Result KSessionRequest::SessionMappings::PushSend(VAddr client, VAddr server, size_t size,
+                                                  KMemoryState state) {
+    ASSERT(m_num_recv == 0);
+    ASSERT(m_num_exch == 0);
+    return this->PushMap(client, server, size, state, m_num_send++);
+}
+
+Result KSessionRequest::SessionMappings::PushReceive(VAddr client, VAddr server, size_t size,
+                                                     KMemoryState state) {
+    ASSERT(m_num_exch == 0);
+    return this->PushMap(client, server, size, state, m_num_send + m_num_recv++);
+}
+
+Result KSessionRequest::SessionMappings::PushExchange(VAddr client, VAddr server, size_t size,
+                                                      KMemoryState state) {
+    return this->PushMap(client, server, size, state, m_num_send + m_num_recv + m_num_exch++);
+}
+
+void KSessionRequest::SessionMappings::Finalize() {
+    if (m_mappings) {
+        KPageBuffer::Free(kernel, reinterpret_cast<KPageBuffer*>(m_mappings));
+        m_mappings = nullptr;
+    }
+}
+
+} // namespace Kernel

src/core/hle/kernel/k_session_request.h

@@ -0,0 +1,307 @@
+// SPDX-FileCopyrightText: Copyright 2022 yuzu Emulator Project
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+#pragma once
+
+#include "core/hle/kernel/k_auto_object.h"
+#include "core/hle/kernel/k_event.h"
+#include "core/hle/kernel/k_memory_block.h"
+#include "core/hle/kernel/k_process.h"
+#include "core/hle/kernel/k_thread.h"
+#include "core/hle/kernel/slab_helpers.h"
+
+namespace Kernel {
+
+class KSessionRequest final : public KSlabAllocated<KSessionRequest>,
+                              public KAutoObject,
+                              public boost::intrusive::list_base_hook<> {
+    KERNEL_AUTOOBJECT_TRAITS(KSessionRequest, KAutoObject);
+
+public:
+    class SessionMappings {
+    private:
+        static constexpr size_t NumStaticMappings = 8;
+
+        class Mapping {
+        public:
+            constexpr void Set(VAddr c, VAddr s, size_t sz, KMemoryState st) {
+                m_client_address = c;
+                m_server_address = s;
+                m_size = sz;
+                m_state = st;
+            }
+
+            constexpr VAddr GetClientAddress() const {
+                return m_client_address;
+            }
+            constexpr VAddr GetServerAddress() const {
+                return m_server_address;
+            }
+            constexpr size_t GetSize() const {
+                return m_size;
+            }
+            constexpr KMemoryState GetMemoryState() const {
+                return m_state;
+            }
+
+        private:
+            VAddr m_client_address;
+            VAddr m_server_address;
+            size_t m_size;
+            KMemoryState m_state;
+        };
+
+    public:
+        explicit SessionMappings(KernelCore& kernel_)
+            : kernel(kernel_), m_mappings(nullptr), m_num_send(), m_num_recv(), m_num_exch() {}
+
+        void Initialize() {}
+        void Finalize();
+
+        size_t GetSendCount() const {
+            return m_num_send;
+        }
+        size_t GetReceiveCount() const {
+            return m_num_recv;
+        }
+        size_t GetExchangeCount() const {
+            return m_num_exch;
+        }
+
+        Result PushSend(VAddr client, VAddr server, size_t size, KMemoryState state);
+        Result PushReceive(VAddr client, VAddr server, size_t size, KMemoryState state);
+        Result PushExchange(VAddr client, VAddr server, size_t size, KMemoryState state);
+
+        VAddr GetSendClientAddress(size_t i) const {
+            return GetSendMapping(i).GetClientAddress();
+        }
+        VAddr GetSendServerAddress(size_t i) const {
+            return GetSendMapping(i).GetServerAddress();
+        }
+        size_t GetSendSize(size_t i) const {
+            return GetSendMapping(i).GetSize();
+        }
+        KMemoryState GetSendMemoryState(size_t i) const {
+            return GetSendMapping(i).GetMemoryState();
+        }
+
+        VAddr GetReceiveClientAddress(size_t i) const {
+            return GetReceiveMapping(i).GetClientAddress();
+        }
+        VAddr GetReceiveServerAddress(size_t i) const {
+            return GetReceiveMapping(i).GetServerAddress();
+        }
+        size_t GetReceiveSize(size_t i) const {
+            return GetReceiveMapping(i).GetSize();
+        }
+        KMemoryState GetReceiveMemoryState(size_t i) const {
+            return GetReceiveMapping(i).GetMemoryState();
+        }
+
+        VAddr GetExchangeClientAddress(size_t i) const {
+            return GetExchangeMapping(i).GetClientAddress();
+        }
+        VAddr GetExchangeServerAddress(size_t i) const {
+            return GetExchangeMapping(i).GetServerAddress();
+        }
+        size_t GetExchangeSize(size_t i) const {
+            return GetExchangeMapping(i).GetSize();
+        }
+        KMemoryState GetExchangeMemoryState(size_t i) const {
+            return GetExchangeMapping(i).GetMemoryState();
+        }
+
+    private:
+        Result PushMap(VAddr client, VAddr server, size_t size, KMemoryState state, size_t index);
+
+        const Mapping& GetSendMapping(size_t i) const {
+            ASSERT(i < m_num_send);
+
+            const size_t index = i;
+            if (index < NumStaticMappings) {
+                return m_static_mappings[index];
+            } else {
+                return m_mappings[index - NumStaticMappings];
+            }
+        }
+
+        const Mapping& GetReceiveMapping(size_t i) const {
+            ASSERT(i < m_num_recv);
+
+            const size_t index = m_num_send + i;
+            if (index < NumStaticMappings) {
+                return m_static_mappings[index];
+            } else {
+                return m_mappings[index - NumStaticMappings];
+            }
+        }
+
+        const Mapping& GetExchangeMapping(size_t i) const {
+            ASSERT(i < m_num_exch);
+
+            const size_t index = m_num_send + m_num_recv + i;
+            if (index < NumStaticMappings) {
+                return m_static_mappings[index];
+            } else {
+                return m_mappings[index - NumStaticMappings];
+            }
+        }
+
+    private:
+        KernelCore& kernel;
+        Mapping m_static_mappings[NumStaticMappings];
+        Mapping* m_mappings;
+        u8 m_num_send;
+        u8 m_num_recv;
+        u8 m_num_exch;
+    };
+
+public:
+    explicit KSessionRequest(KernelCore& kernel_)
+        : KAutoObject(kernel_), m_mappings(kernel_), m_thread(nullptr), m_server(nullptr),
+          m_event(nullptr) {}
+
+    static KSessionRequest* Create(KernelCore& kernel) {
+        KSessionRequest* req = KSessionRequest::Allocate(kernel);
+        if (req != nullptr) [[likely]] {
+            KAutoObject::Create(req);
+        }
+        return req;
+    }
+
+    void Destroy() override {
+        this->Finalize();
+        KSessionRequest::Free(kernel, this);
+    }
+
+    void Initialize(KEvent* event, uintptr_t address, size_t size) {
+        m_mappings.Initialize();
+
+        m_thread = GetCurrentThreadPointer(kernel);
+        m_event = event;
+        m_address = address;
+        m_size = size;
+
+        m_thread->Open();
+        if (m_event != nullptr) {
+            m_event->Open();
+        }
+    }
+
+    static void PostDestroy(uintptr_t arg) {}
+
+    KThread* GetThread() const {
+        return m_thread;
+    }
+    KEvent* GetEvent() const {
+        return m_event;
+    }
+    uintptr_t GetAddress() const {
+        return m_address;
+    }
+    size_t GetSize() const {
+        return m_size;
+    }
+    KProcess* GetServerProcess() const {
+        return m_server;
+    }
+
+    void SetServerProcess(KProcess* process) {
+        m_server = process;
+        m_server->Open();
+    }
+
+    void ClearThread() {
+        m_thread = nullptr;
+    }
+    void ClearEvent() {
+        m_event = nullptr;
+    }
+
+    size_t GetSendCount() const {
+        return m_mappings.GetSendCount();
+    }
+    size_t GetReceiveCount() const {
+        return m_mappings.GetReceiveCount();
+    }
+    size_t GetExchangeCount() const {
+        return m_mappings.GetExchangeCount();
+    }
+
+    Result PushSend(VAddr client, VAddr server, size_t size, KMemoryState state) {
+        return m_mappings.PushSend(client, server, size, state);
+    }
+
+    Result PushReceive(VAddr client, VAddr server, size_t size, KMemoryState state) {
+        return m_mappings.PushReceive(client, server, size, state);
+    }
+
+    Result PushExchange(VAddr client, VAddr server, size_t size, KMemoryState state) {
+        return m_mappings.PushExchange(client, server, size, state);
+    }
+
+    VAddr GetSendClientAddress(size_t i) const {
+        return m_mappings.GetSendClientAddress(i);
+    }
+    VAddr GetSendServerAddress(size_t i) const {
+        return m_mappings.GetSendServerAddress(i);
+    }
+    size_t GetSendSize(size_t i) const {
+        return m_mappings.GetSendSize(i);
+    }
+    KMemoryState GetSendMemoryState(size_t i) const {
+        return m_mappings.GetSendMemoryState(i);
+    }
+
+    VAddr GetReceiveClientAddress(size_t i) const {
+        return m_mappings.GetReceiveClientAddress(i);
+    }
+    VAddr GetReceiveServerAddress(size_t i) const {
+        return m_mappings.GetReceiveServerAddress(i);
+    }
+    size_t GetReceiveSize(size_t i) const {
+        return m_mappings.GetReceiveSize(i);
+    }
+    KMemoryState GetReceiveMemoryState(size_t i) const {
+        return m_mappings.GetReceiveMemoryState(i);
+    }
+
+    VAddr GetExchangeClientAddress(size_t i) const {
+        return m_mappings.GetExchangeClientAddress(i);
+    }
+    VAddr GetExchangeServerAddress(size_t i) const {
+        return m_mappings.GetExchangeServerAddress(i);
+    }
+    size_t GetExchangeSize(size_t i) const {
+        return m_mappings.GetExchangeSize(i);
+    }
+    KMemoryState GetExchangeMemoryState(size_t i) const {
+        return m_mappings.GetExchangeMemoryState(i);
+    }
+
+private:
+    // NOTE: This is public and virtual in Nintendo's kernel.
+    void Finalize() {
+        m_mappings.Finalize();
+
+        if (m_thread) {
+            m_thread->Close();
+        }
+        if (m_event) {
+            m_event->Close();
+        }
+        if (m_server) {
+            m_server->Close();
+        }
+    }
+
+private:
+    SessionMappings m_mappings;
+    KThread* m_thread;
+    KProcess* m_server;
+    KEvent* m_event;
+    uintptr_t m_address;
+    size_t m_size;
+};
+
+} // namespace Kernel

src/core/hle/kernel/k_shared_memory_info.h

@@ -15,7 +15,8 @@ class KSharedMemoryInfo final : public KSlabAllocated<KSharedMemoryInfo>,
                                 public boost::intrusive::list_base_hook<> {
 
 public:
-    explicit KSharedMemoryInfo() = default;
+    explicit KSharedMemoryInfo(KernelCore&) {}
+    KSharedMemoryInfo() = default;
 
     constexpr void Initialize(KSharedMemory* shmem) {
         shared_memory = shmem;

src/core/hle/kernel/k_thread_local_page.h

@@ -26,7 +26,7 @@ public:
     static_assert(RegionsPerPage > 0);
 
 public:
-    constexpr explicit KThreadLocalPage(VAddr addr = {}) : m_virt_addr(addr) {
+    constexpr explicit KThreadLocalPage(KernelCore&, VAddr addr = {}) : m_virt_addr(addr) {
         m_is_region_free.fill(true);
     }
 

src/core/hle/kernel/kernel.h

@@ -47,6 +47,7 @@ class KResourceLimit;
 class KScheduler;
 class KServerSession;
 class KSession;
+class KSessionRequest;
 class KSharedMemory;
 class KSharedMemoryInfo;
 class KThread;
@@ -360,6 +361,8 @@ public:
             return slab_heap_container->page_buffer;
         } else if constexpr (std::is_same_v<T, KThreadLocalPage>) {
             return slab_heap_container->thread_local_page;
+        } else if constexpr (std::is_same_v<T, KSessionRequest>) {
+            return slab_heap_container->session_request;
         }
     }
 
@@ -422,6 +425,7 @@ private:
         KSlabHeap<KCodeMemory> code_memory;
         KSlabHeap<KPageBuffer> page_buffer;
         KSlabHeap<KThreadLocalPage> thread_local_page;
+        KSlabHeap<KSessionRequest> session_request;
     };
 
     std::unique_ptr<SlabHeapContainer> slab_heap_container;

src/core/hle/kernel/slab_helpers.h

@@ -24,7 +24,7 @@ public:
     }
 
     static Derived* Allocate(KernelCore& kernel) {
-        return kernel.SlabHeap<Derived>().Allocate();
+        return kernel.SlabHeap<Derived>().Allocate(kernel);
     }
 
     static void Free(KernelCore& kernel, Derived* obj) {

src/core/hle/service/sm/sm_controller.cpp

@@ -15,9 +15,10 @@
 namespace Service::SM {
 
 void Controller::ConvertCurrentObjectToDomain(Kernel::HLERequestContext& ctx) {
-    ASSERT_MSG(!ctx.Session()->IsDomain(), "Session is already a domain");
+    ASSERT_MSG(!ctx.Session()->GetSessionRequestManager()->IsDomain(),
+               "Session is already a domain");
     LOG_DEBUG(Service, "called, server_session={}", ctx.Session()->GetId());
-    ctx.Session()->ConvertToDomain();
+    ctx.Session()->GetSessionRequestManager()->ConvertToDomainOnRequestEnd();
 
     IPC::ResponseBuilder rb{ctx, 3};
     rb.Push(ResultSuccess);