--- a/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.hpp	Wed Apr 22 17:05:00 2015 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/concurrentMark.hpp	Mon Apr 27 10:04:26 2015 +0200
@@ -139,6 +139,11 @@
   static size_t compute_size(size_t heap_size);
   // Returns the amount of bytes on the heap between two marks in the bitmap.
   static size_t mark_distance();
+  // Returns how many bytes (or bits) of the heap a single byte (or bit) of the
+  // mark bitmap corresponds to. This is the same as the mark distance above.
+  static size_t heap_map_factor() {
+    return mark_distance();
+  }
 
   CMBitMap() : CMBitMapRO(LogMinObjAlignment), _listener() { _listener.set_bitmap(this); }
 

--- a/hotspot/src/share/vm/gc_implementation/g1/g1BlockOffsetTable.hpp	Wed Apr 22 17:05:00 2015 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1BlockOffsetTable.hpp	Mon Apr 27 10:04:26 2015 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2001, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -179,6 +179,11 @@
     return ReservedSpace::allocation_align_size_up(number_of_slots);
   }
 
+  // Returns how many bytes of the heap a single byte of the BOT corresponds to.
+  static size_t heap_map_factor() {
+    return N_bytes;
+  }
+
   enum SomePublicConstants {
     LogN = 9,
     LogN_words = LogN - LogHeapWordSize,

--- a/hotspot/src/share/vm/gc_implementation/g1/g1CardCounts.cpp	Wed Apr 22 17:05:00 2015 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CardCounts.cpp	Mon Apr 27 10:04:26 2015 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013, 2014, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -39,6 +39,17 @@
   _counts->clear_range(mr);
 }
 
+size_t G1CardCounts::compute_size(size_t mem_region_size_in_words) {
+  // We keep card counts for every card, so the size of the card counts table must
+  // be the same as the card table.
+  return G1SATBCardTableLoggingModRefBS::compute_size(mem_region_size_in_words);
+}
+
+size_t G1CardCounts::heap_map_factor() {
+  // See G1CardCounts::compute_size() why we reuse the card table value.
+  return G1SATBCardTableLoggingModRefBS::heap_map_factor();
+}
+
 void G1CardCounts::clear_range(size_t from_card_num, size_t to_card_num) {
   if (has_count_table()) {
     assert(from_card_num < to_card_num,

--- a/hotspot/src/share/vm/gc_implementation/g1/g1CardCounts.hpp	Wed Apr 22 17:05:00 2015 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CardCounts.hpp	Mon Apr 27 10:04:26 2015 +0200
@@ -101,6 +101,14 @@
  public:
   G1CardCounts(G1CollectedHeap* g1h);
 
+  // Return the number of slots needed for a card counts table
+  // that covers mem_region_words words.
+  static size_t compute_size(size_t mem_region_size_in_words);
+
+  // Returns how many bytes of the heap a single byte of the card counts table
+  // corresponds to.
+  static size_t heap_map_factor();
+
   void initialize(G1RegionToSpaceMapper* mapper);
 
   // Increments the refinement count for the given card.

--- a/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Wed Apr 22 17:05:00 2015 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1CollectedHeap.cpp	Mon Apr 27 10:04:26 2015 +0200
@@ -1890,24 +1890,24 @@
   G1RegionToSpaceMapper* bot_storage =
     create_aux_memory_mapper("Block offset table",
                              G1BlockOffsetSharedArray::compute_size(g1_rs.size() / HeapWordSize),
-                             G1BlockOffsetSharedArray::N_bytes);
+                             G1BlockOffsetSharedArray::heap_map_factor());
 
   ReservedSpace cardtable_rs(G1SATBCardTableLoggingModRefBS::compute_size(g1_rs.size() / HeapWordSize));
   G1RegionToSpaceMapper* cardtable_storage =
     create_aux_memory_mapper("Card table",
                              G1SATBCardTableLoggingModRefBS::compute_size(g1_rs.size() / HeapWordSize),
-                             G1BlockOffsetSharedArray::N_bytes);
+                             G1SATBCardTableLoggingModRefBS::heap_map_factor());
 
   G1RegionToSpaceMapper* card_counts_storage =
     create_aux_memory_mapper("Card counts table",
-                             G1BlockOffsetSharedArray::compute_size(g1_rs.size() / HeapWordSize),
-                             G1BlockOffsetSharedArray::N_bytes);
+                             G1CardCounts::compute_size(g1_rs.size() / HeapWordSize),
+                             G1CardCounts::heap_map_factor());
 
   size_t bitmap_size = CMBitMap::compute_size(g1_rs.size());
   G1RegionToSpaceMapper* prev_bitmap_storage =
-    create_aux_memory_mapper("Prev Bitmap", bitmap_size, CMBitMap::mark_distance());
+    create_aux_memory_mapper("Prev Bitmap", bitmap_size, CMBitMap::heap_map_factor());
   G1RegionToSpaceMapper* next_bitmap_storage =
-    create_aux_memory_mapper("Next Bitmap", bitmap_size, CMBitMap::mark_distance());
+    create_aux_memory_mapper("Next Bitmap", bitmap_size, CMBitMap::heap_map_factor());
 
   _hrm.initialize(heap_storage, prev_bitmap_storage, next_bitmap_storage, bot_storage, cardtable_storage, card_counts_storage);
   g1_barrier_set()->initialize(cardtable_storage);

--- a/hotspot/src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.hpp	Wed Apr 22 17:05:00 2015 +0200
+++ b/hotspot/src/share/vm/gc_implementation/g1/g1SATBCardTableModRefBS.hpp	Mon Apr 27 10:04:26 2015 +0200
@@ -153,6 +153,11 @@
     return ReservedSpace::allocation_align_size_up(number_of_slots);
   }
 
+  // Returns how many bytes of the heap a single byte of the Card Table corresponds to.
+  static size_t heap_map_factor() {
+    return CardTableModRefBS::card_size;
+  }
+
   G1SATBCardTableLoggingModRefBS(MemRegion whole_heap);
 
   virtual void initialize() { }