Multiple changes regarding channels. Mainly channels are now stream
based and can handle partial reads or writes. Channels now use the
kernel buffers area with the related buffer_cache. Added a fake stdout
stream channel and kernel task to read its contents to the screen in
preparation for handing channels as stdin/stdout to processes.
Renamed and genericized the stack_cache class to manage any address
range area of buffers or memory regions. Removed singleton and created
some globals that map to different address regions (kernel stacks,
kernel buffers).
Tags: vmem virtual memeory
When committing an area of vmem and splitting from a larger block, the
block that is returned was set to the unknown state, and the leading
block was incorrectly set to the desired state.
Also remove extra unused thread ctor.
We were previously allocating kernel stacks as large objects on the
heap. Now keep track of areas of the kernel stack area that are in use,
and allocate them from there. Also required actually implementing
vm_space::commit(). This still needs more work.
Add a system call to assert signals on a given object, only within the
range of user-settable signals. Also made object_wait return
immediately if any of the given signals are already set.
Add the channel object for sending messages between threads. Currently
no good of passing channels to other threads, but global variables in a
single process work. Currently channels are slow and do double copies,
need to refine more.
Tags: ipc
Implement the syscalls necessary for threads to create other threads in
their same process. This involved rearranging a number of syscalls, as
well as implementing object_wait and a basic implementation of a
process' list of handles.
The TCB is always stored at a constant offset within the thread object.
So instead of carrying an extra pointer, just implement thread::from_tcb
to get the thread.
Re-implent the concept of processes as separate from threads, and as a
kobject API object. Also improve scheduler::prune which was doing some
unnecessary iterations.
Look up the global constructor list that the linker outputs, and run
them all. Required creation of the `kutil::no_construct` template for
objects that are constructed before the global constructors are run.
Also split the `memory_initialize` function into two - one for just
those objects that need to happen before the global ctors, and one
after.
Tags: memory c++
Many kernel objects had to keep a hold of refrences to allocators in
order to pass them on down the call chain. Remove those explicit
refrences and use `operator new`, `operator delete`, and define new
`kalloc` and `kfree`.
Also remove `slab_allocator` and replace it with a new mixin for slab
allocation, `slab_allocated`, that overrides `operator new` and
`operator free` for its subclass.
Remove some no longer used related headers, `buddy_allocator.h` and
`address_manager.h`
Tags: memory
