Boot with virtual == physical to get closer to native Linux.
1) This allows us to get alot closer to booting bzImages.
2) It means we don't have to know page_offset.
3) The Guest needs to modify the boot pagetables to create the
PAGE_OFFSET mapping before jumping to C code.
4) guest_pa() walks the page tables rather than using page_offset.
5) We don't use page_offset to figure out whether to emulate: it was
always kinda quesationable, and won't work for instructions done
before remapping (bzImage unpacking in particular).
6) We still want the kernel address for tlb flushing: have the initial
hypercall give us that, too.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
diff --git a/include/linux/lguest.h b/include/linux/lguest.h
index 0830522..8beb291 100644
--- a/include/linux/lguest.h
+++ b/include/linux/lguest.h
@@ -44,11 +44,14 @@
unsigned long reserve_mem;
/* KHz for the TSC clock. */
u32 tsc_khz;
+ /* Page where the top-level pagetable is */
+ unsigned long pgdir;
/* Fields initialized by the Guest at boot: */
/* Instruction range to suppress interrupts even if enabled */
unsigned long noirq_start, noirq_end;
-
+ /* Address above which page tables are all identical. */
+ unsigned long kernel_address;
/* The vector to try to use for system calls (0x40 or 0x80). */
unsigned int syscall_vec;
};