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>

1 files changed, 3 insertions, 5 deletions

diff --git a/drivers/lguest/lg.h b/drivers/lguest/lg.h
index 7408cebe995..e4845d7f068 100644
--- a/drivers/lguest/lg.h
+++ b/drivers/lguest/lg.h
@@ -63,7 +63,7 @@ struct lguest
         /* This provides the offset to the base of guest-physical
          * memory in the Launcher. */
         void __user *mem_base;
-        u32 page_offset;
+        unsigned long kernel_address;
         u32 cr2;
         int halted;
         int ts;
@@ -165,6 +165,8 @@ void guest_set_pte(struct lguest *lg, unsigned long gpgdir,
 void map_switcher_in_guest(struct lguest *lg, struct lguest_pages *pages);
 int demand_page(struct lguest *info, unsigned long cr2, int errcode);
 void pin_page(struct lguest *lg, unsigned long vaddr);
+unsigned long guest_pa(struct lguest *lg, unsigned long vaddr);
+void page_table_guest_data_init(struct lguest *lg);
 
 /* <arch>/core.c: */
 void lguest_arch_host_init(void);
@@ -229,9 +231,5 @@ do {								\
 } while(0)
 /* (End of aside) :*/
 
-static inline unsigned long guest_pa(struct lguest *lg, unsigned long vaddr)
-{
-        return vaddr - lg->page_offset;
-}
 #endif  /* __ASSEMBLY__ */
 #endif  /* _LGUEST_H */