Commit graph

8 commits

Author SHA1 Message Date
Andreas Kling
98f76f0153 Flush the TLB after modifying page tables.
This is a very inefficient naive implementation, but it gets us going.
Mapping tasks in and out of a shared address space now totally works.
2018-10-23 11:03:56 +02:00
Andreas Kling
fe237ee215 Lots of hacking:
- Turn Keyboard into a CharacterDevice (85,1) at /dev/keyboard.
- Implement MM::unmapRegionsForTask() and MM::unmapRegion()
- Save SS correctly on interrupt.
- Add a simple Spawn syscall for launching another process.
- Move a bunch of IO syscall debug output behind DEBUG_IO.
- Have ASSERT do a "cli" immediately when failing.
  This makes the output look proper every time.
- Implement a bunch of syscalls in LibC.
- Add a simple shell ("sh"). All it can do now is read a line
  of text from /dev/keyboard and then try launching the specified
  executable by calling spawn().

There are definitely bugs in here, but we're moving on forward.
2018-10-23 10:12:50 +02:00
Andreas Kling
b824f15619 Launching an arbitrary ELF executable from disk works! :^)
This is so cool! It's a bit messy now with two Task constructors,
but eventually they should fold into a single constructor somehow.
2018-10-22 15:43:02 +02:00
Andreas Kling
79ffdb7205 A lot of hacking:
- More work on funneling console output through Console.
- init() now breaks off into a separate task ASAP.
- ..this leaves the "colonel" task as a simple hlt idle loop.
- Mask all IRQs on startup (except IRQ2 for slave passthru)
- Fix underallocation bug in Task::allocateRegion().
- Remember how many times each Task has been scheduled.

The panel and scheduling banner are disabled until I get things
working nicely in the (brave) new Console world.
2018-10-22 11:15:16 +02:00
Andreas Kling
d5ec18027e Protect the first 4 KB of memory.
This makes null pointers crashy, tremendously useful :^)
2018-10-21 21:59:11 +02:00
Andreas Kling
3649638259 Add Regions concept to Task. 2018-10-18 14:55:20 +02:00
Andreas Kling
f67d695254 More paging stuff.
The test userspace process now runs at linear address 0x300000 which is
mapped to a dynamically allocated page from the MemoryManager. Cool!
2018-10-18 13:05:00 +02:00
Andreas Kling
77299cf54d Add basic paging. Only identity maps the bottom 4MB as a start. 2018-10-17 23:13:55 +02:00