sparc64: Define VA hole at run time, rather than at compile time.

Now that we use 4-level page tables, we can provide up to 53-bits of
virtual address space to the user.

Adjust the VA hole based upon the capabilities of the cpu type probed.

Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Bob Picco <bob.picco@oracle.com>

1 files changed, 4 insertions, 11 deletions

diff --git a/arch/sparc/include/asm/page_64.h b/arch/sparc/include/asm/page_64.h
index 09ceb68e72b7..2211a8036bfa 100644
--- a/arch/sparc/include/asm/page_64.h
+++ b/arch/sparc/include/asm/page_64.h
@@ -102,21 +102,14 @@ typedef unsigned long pgprot_t;
 
 typedef pte_t *pgtable_t;
 
-/* These two values define the virtual address space range in which we
- * must forbid 64-bit user processes from making mappings.  It used to
- * represent precisely the virtual address space hole present in most
- * early sparc64 chips including UltraSPARC-I.  But now it also is
- * further constrained by the limits of our page tables, which is
- * 43-bits of virtual address.
- */
-#define SPARC64_VA_HOLE_TOP     _AC(0xfffffc0000000000,UL)
-#define SPARC64_VA_HOLE_BOTTOM  _AC(0x0000040000000000,UL)
+extern unsigned long sparc64_va_hole_top;
+extern unsigned long sparc64_va_hole_bottom;
 
 /* The next two defines specify the actual exclusion region we
  * enforce, wherein we use a 4GB red zone on each side of the VA hole.
  */
-#define VA_EXCLUDE_START (SPARC64_VA_HOLE_BOTTOM - (1UL << 32UL))
-#define VA_EXCLUDE_END   (SPARC64_VA_HOLE_TOP + (1UL << 32UL))
+#define VA_EXCLUDE_START (sparc64_va_hole_bottom - (1UL << 32UL))
+#define VA_EXCLUDE_END   (sparc64_va_hole_top + (1UL << 32UL))
 
 #define TASK_UNMAPPED_BASE      (test_thread_flag(TIF_32BIT) ? \
                                  _AC(0x0000000070000000,UL) : \