We now have DevFileSystem which is derived from RamFileSystem. All
devices are RamInodes. We don't have separate DeviceManager anymore.
To iterate over devices, you can loop througn every inode in devfs.
DiskCache now consists of PageCaches which are caches of contiguous
sectors. This allows the disk cache to be ordered and faster traversal.
We seem to have a problem somewhere during reading. The stack gets
corrupted.
We now load ELF files to VirtualRanges instead of using kmalloc.
We have only a fixed 1 MiB kmalloc for big allocations and this
allows loading files even when they don't fit in there.
This caused me to rewrite the whole ELF loading process since the
loaded ELF is not in memory mapped by every process.
Virtual ranges allow you to zero out the memory and to copy into
them from arbitary byte buffers.
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.
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
We used to block on all process access. This meant that shell
reading the keyboard input would block all VFS access making disk
accesses practically impossible. We now block only when it is
necessary :)
This is a big commit that was kinda hard to split to smaller ones.
Essentially we now look at all the mass storage devices from PCI
and initialize (P)ATA devices. This doesn't provide any more functionality
but better abstractions and everything doesn't have to be on its old
default port that might be different for modern computers.
Bananymous