This commit ensures that all backing memory allocated for the Guest CPU
is aligned to 256 bytes. This due to how gpu memory works and the heavy
constraints it has in the alignment of physical memory.
The kernel makes sure that the given size to unmap is always the same
size as the entire region managed by the shared memory instance,
otherwise it returns an error code signifying an invalid size.
This is similarly done for transfer memory (which we already check for).
Given we already pass in a reference to the kernel that the shared
memory instance is created under, we can just use that to check the
current process, rather than using the global accessor functions.
This allows removing direct dependency on the system instance entirely.
The Process object kept itself alive indefinitely because its handle_table
contains a SharedMemory object which owns a reference to the same Process object,
creating a circular ownership scenario.
Break that up by storing only a non-owning pointer in the SharedMemory object.
This was only ever public so that code could check whether or not a
handle was valid or not. Instead of exposing the object directly and
allowing external code to potentially mess with the map contents, we
just provide a member function that allows checking whether or not a
handle is valid.
This makes all member variables of the VMManager class private except
for the page table.
Both member functions assume the passed in target process will not be
null. Instead of making this assumption implicit, we can change the
functions to be references and enforce this at the type-system level.
Makes the interface nicer to use in terms of 64-bit code, as it makes it
less likely for one to get truncation warnings (and also makes sense in
the context of the rest of the interface where 64-bit types are used for
sizes and offsets
Makes the public interface consistent in terms of how accesses are done
on a process object. It also makes it slightly nicer to reason about the
logic of the process class, as we don't want to expose everything to
external code.
The locations of these can actually vary depending on the address space
layout, so we shouldn't be using these when determining where to map
memory or be using them as offsets for calculations. This keeps all the
memory ranges flexible and malleable based off of the virtual memory
manager instance state.
As means to pave the way for getting rid of global state within core,
This eliminates kernel global state by removing all globals. Instead
this introduces a KernelCore class which acts as a kernel instance. This
instance lives in the System class, which keeps its lifetime contained
to the lifetime of the System class.
This also forces the kernel types to actually interact with the main
kernel instance itself instead of having transient kernel state placed
all over several translation units, keeping everything together. It also
has a nice consequence of making dependencies much more explicit.
This also makes our initialization a tad bit more correct. Previously we
were creating a kernel process before the actual kernel was initialized,
which doesn't really make much sense.
The KernelCore class itself follows the PImpl idiom, which allows
keeping all the implementation details sealed away from everything else,
which forces the use of the exposed API and allows us to avoid any
unnecessary inclusions within the main kernel header.
This amends cases where crashes can occur that were missed due to the
odd way the previous code was set up (using 3DS memory regions that
don't exist).
This makes the formatting expectations more obvious (e.g. any zero padding specified
is padding that's entirely dedicated to the value being printed, not any pretty-printing
that also gets tacked on).
Applications can request the kernel to allocate a piece of the linear heap for them when creating a shared memory object.
Shared memory areas are now properly mapped into the target processes when calling svcMapMemoryBlock.
Removed the APT Shared Font hack as it is no longer needed.
memory.cpp/h contains definitions related to acessing memory and
configuring the address space
mem_map.cpp/h contains higher-level definitions related to configuring
the address space accoording to the kernel and allocating memory.
