powerpc/mm: Add support for handling > 512TB address in SLB miss

[linux-2.6-block.git] / arch / powerpc / mm / slb_low.S

diff --git a/arch/powerpc/mm/slb_low.S b/arch/powerpc/mm/slb_low.S
index 2c7c717fd2ea8cbe57b9066652aa0d762ce6d789..a83fbd2a4a245dadeb9840b5480d85cff5fa6e26 100644 (file)
--- a/arch/powerpc/mm/slb_low.S
+++ b/arch/powerpc/mm/slb_low.S
@@ -75,10 +75,15 @@ ALT_MMU_FTR_SECTION_END_IFCLR(MMU_FTR_68_BIT_VA)
  */
 _GLOBAL(slb_allocate)
        /*
-        * check for bad kernel/user address
-        * (ea & ~REGION_MASK) >= PGTABLE_RANGE
+        * Check if the address falls within the range of the first context, or
+        * if we may need to handle multi context. For the first context we
+        * allocate the slb entry via the fast path below. For large address we
+        * branch out to C-code and see if additional contexts have been
+        * allocated.
+        * The test here is:
+        *   (ea & ~REGION_MASK) >= (1ull << MAX_EA_BITS_PER_CONTEXT)
         */
-       rldicr. r9,r3,4,(63 - H_PGTABLE_EADDR_SIZE - 4)
+       rldicr. r9,r3,4,(63 - MAX_EA_BITS_PER_CONTEXT - 4)
        bne-    8f
 
        srdi    r9,r3,60                /* get region */