The only functional change is the error handling of GSP_GPU::ReadHWRegs function. We previously didn't return error codes (not even for success). The new returns were found by reverse engineering the GSP module.
Kernel/Threads: Add a new thread status that will allow using a Kernel::Event to put a guest thread to sleep inside an HLE handler until said event is signaled
An HLE service function that wants to perform an async operation should put the caller guest thread to sleep using SleepClientThread, passing in a callback to execute when the thread is resumed.
SleepClientThread returns a ThreadContinuationToken that should be stored and used with ContinueClientThread to resume the guest thread when the host async operation completes.
Copy the IPC command buffer to/from the request context before/after the
handler is invoked. This is part of a move away from using global data
for handling IPC requests.
The old "Interface" class had a few problems such as using free
functions (Which didn't allow you to write the service handler as if it
were a regular class.) which weren't very extensible. (Only received one
parameter with a pointer to the Interface object.)
The new ServiceFramework aims to solve these problems by working with
member functions and passing a generic context struct as parameter. This
struct can be extended in the future without having to update all
existing service implementations.
This allows attaching a HLE handle to a ServerPort at any point after it
is created, allowing port/session creation to be generic between HLE and
regular services.
Sessions and Ports are now detached from each other.
HLE services are handled by means of a SessionRequestHandler class, Interface now inherits from this class.
The File and Directory classes are no longer kernel objects, but SessionRequestHandlers instead, bound to a ServerSession when requested.
File::OpenLinkFile now creates a new session pair and binds the File instance to it.
All handles obtained via srv::GetServiceHandle or svcConnectToPort are references to ClientSessions.
Service modules will wait on the counterpart of those ClientSessions (Called ServerSessions) using svcReplyAndReceive or svcWaitSynchronization[1|N], and will be awoken when a SyncRequest is performed.
HLE Interfaces are now ClientPorts which override the HandleSyncRequest virtual member function to perform command handling immediately.
