- Let allocateSelector() specify number of pages to allocate.
- Let findSelector() specify if this is a code or data segment.
- Let findSelector() choose if this is a code or data segment
if the caller doesn't know (DosFlatToSel(), etc).
Now we save off the stack pointer and immediately jmp back to 32-bit. This is
slightly easier to debug (gdb doesn't get confused by addresses, registers or
disassembly), and puts all the 32-bit registers in a 32-bit code segment, to
keep things sane.
Also: doesn't write duplicate instructions to update %ds and %es if they are
the same values in Linux land.
This gets us everything we need (I hope!) to support 16-bit code in LX
binaries and call into 16-bit OS/2 APIs. This is just enough to call
into VioGetMode() (which isn't otherwise implemented yet) as an example.
If this is ever used Winelib-style to provide an OS/2 API to native Linux
binaries, the 16-bit system APIs are 32-bit clean and C callable, as one
might expect them to be. All the tapdancing is to support existing LX
binaries in the loader and bridge between the 32-bit clean APIs and
existing 16-bit code that expects to call 16-bit APIs.
This was a staggering amount of effort, but yay!
Other fixes and improvements probably leaked into this commit, as a
lot of code got touched and a lot of research and debugging took place.
Ryan C. Gordon