* Move some of the memory bootstrapping and the DDB startup earlier.
* Always put the IDT and the initial GDT and LDT in a separate page.
* Various minor changes.
* Call gdt_init() earlier on.
* Don't bother to check for TSS and LDT descriptors in verr_gdt().
* Nuke the sti special case for trace and breakpoint traps.
* Move some variable declarations into more appropriate locations.
/*
* void bioscall(int function, struct apmregs *regs):
* call the BIOS interrupt "function" from real mode with
* registers as specified in "regs"
* (for the flags, though, only these flags are passed to the BIOS;
* the remainder come from the flags register at the time of the call:
* (PSL_C|PSL_PF|PSL_AF|PSL_Z|PSL_N|PSL_D|PSL_V)
*
* Fills in *regs with registers as returned by BIOS.
*/
Thanks to Charles Hannum for complaining and inspiring me to hack this
together.
Map kernel stacks only at unique addresses.
Use one TSS per process.
Add sysarch calls for modifying IOPL and the I/O permission bitmap.
Add a compacting GDT entry allocator, for TSS and LDT selectors.
Enable modifying %fs and %gs with PT_SETREGS.
Sanitize various bits of code.
creating segment descriptors. Add the duplicate system call gate used by
BSD/OS 2.0 executables. Prototype setsegment() and setgate(), and fix a bogon
caught by this.
christos