Add support for async transfers by using a separate kernel task to poll
a list of active async transfers on a set time interval, and invoke
their user-provided callback function when they are complete. Also add
support for the interrupt class of transfers, building off of this async
functionality.
Until now, our kernel has reimplemented a number of AK classes to
provide automatic internal locking:
- RefPtr
- NonnullRefPtr
- WeakPtr
- Weakable
This patch renames the Kernel classes so that they can coexist with
the original AK classes:
- RefPtr => LockRefPtr
- NonnullRefPtr => NonnullLockRefPtr
- WeakPtr => LockWeakPtr
- Weakable => LockWeakable
The goal here is to eventually get rid of the Lock* classes in favor of
using external locking.
Instead of having two separate implementations of AK::RefCounted, one
for userspace and one for kernelspace, there is now RefCounted and
AtomicRefCounted.
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace!
This was a slightly tedious refactoring that took a long time, so it's
not unlikely that some bugs crept in.
Nevertheless, it does pass basic functionality testing, and it's just
real nice to finally see the same pattern in all contexts. :^)
This commit moves the KResult and KResultOr objects to Kernel/API to
signify that they may now be freely used by userspace code at points
where a syscall-related error result is to be expected. It also exposes
KResult and KResultOr to the global namespace to make it nicer to use
for userspace code.
This removes Pipes dependency on the UHCIController by introducing a
controller base class. This will be used to implement other controllers
such as OHCI.
Additionally, there can be multiple instances of a UHCI controller.
For example, multiple UHCI instances can be required for systems with
EHCI controllers. EHCI relies on using multiple of either UHCI or OHCI
controllers to drive USB 1.x devices.
This means UHCIController can no longer be a singleton. Multiple
instances of it can now be created and passed to the device and then to
the pipe.
To handle finding and creating these instances, USBManagement has been
introduced. It has the same pattern as the other management classes
such as NetworkManagement.
