On SYS_ALLOC we will add a new FixedWidthAllocator if the old ones
are already full or we don't have one with proper size. This allows
arbitary number of allocations as long as you have enough memory
available :)
Next I will be writing a general allocator for allocations larger
than 4096 bytes which should make SYS_ALLOC syscall complete :)
MMU moved to namespace kernel
Kernel::Memory::Heap moved to just Kernel
MMU::map_{page,range} renamed to identity_map_{page,range}
Add MMU::get_page_flags
We now assign every (userspace) process its own MMU which we load
in scheduler. This allows every process to have separate virtual
address space.
This is very hackish implementations but it works for now
Also only process can now add threads to scheduler. Nobody should
have raw access to scheduler and everything should be through
Process::current() or irqs (reschedules)
We don't store the error message anymore in BAN::Error.
Instead we store a error code that can be mapped into a string.
This allows BAN::Error to only take 4 bytes instead of 128.
We should also make some kernel initialization just panic instead
of returning errors since they are required for succesfull boot
anyway.
Now after each interrupt we will ask the scheduler to reschedule
if the current thread is the idle thread. This allows semaphore
unblocking to be practically instant when there is only one thread
executing.
Now disk reading is back to ~3 MB/s for single threaded process
Reading is now much slower at ~500 kB/s it was around 3 MB/s.
This is probably mostly due semaphore blocking taking atleast
until next reschedule (1 ms itervals). This will be a problem
as long as we are using only single processor.
I could try to use {READ/WRITE}_MULTIPLE commands, but since
most of the disk reads are 2 sectors (inode block size) this
will at most double the speed.
Most efficient speed up would of course be caching disk access
data and inodes overall.
The API is kinda weird since device reads/writes go from
ATADevice -> ATAController -> ATADevice
but this is for now atleast necessary since ATAController has(?)
to keep all devices from using the disks at the same time