diff -r e76d5ffa6b36 -r 79783b86b586 src/mem/protocol/RubySlicc_Types.sm
--- a/src/mem/protocol/RubySlicc_Types.sm	Thu Mar 31 12:19:14 2011 -0700
+++ b/src/mem/protocol/RubySlicc_Types.sm	Thu Mar 31 12:19:35 2011 -0700
@@ -134,6 +134,7 @@
   bool cacheAvail(Address);
   Address cacheProbe(Address);
   AbstractCacheEntry allocate(Address, AbstractCacheEntry);
+  void allocateVoid(Address, AbstractCacheEntry);
   void deallocate(Address);
   AbstractCacheEntry lookup(Address);
   bool isTagPresent(Address);
diff -r e76d5ffa6b36 -r 79783b86b586 src/mem/ruby/system/CacheMemory.hh
--- a/src/mem/ruby/system/CacheMemory.hh	Thu Mar 31 12:19:14 2011 -0700
+++ b/src/mem/ruby/system/CacheMemory.hh	Thu Mar 31 12:19:35 2011 -0700
@@ -83,6 +83,7 @@
 
     // find an unused entry and sets the tag appropriate for the address
     AbstractCacheEntry* allocate(const Address& address, AbstractCacheEntry* new_entry);
+    void allocateVoid(const Address& address, AbstractCacheEntry* new_entry);
 
     // Explicitly free up this address
     void deallocate(const Address& address);
diff -r e76d5ffa6b36 -r 79783b86b586 src/mem/ruby/system/CacheMemory.cc
--- a/src/mem/ruby/system/CacheMemory.cc	Thu Mar 31 12:19:14 2011 -0700
+++ b/src/mem/ruby/system/CacheMemory.cc	Thu Mar 31 12:19:35 2011 -0700
@@ -283,6 +283,35 @@
 }
 
 void
+CacheMemory::allocateVoid(const Address& address, AbstractCacheEntry* entry)
+{
+    assert(address == line_address(address));
+    assert(!isTagPresent(address));
+    assert(cacheAvail(address));
+    DPRINTF(RubyCache, "address: %s\n", address);
+
+    // Find the first open slot
+    Index cacheSet = addressToCacheSet(address);
+    std::vector<AbstractCacheEntry*> &set = m_cache[cacheSet];
+    for (int i = 0; i < m_cache_assoc; i++) {
+        if (!set[i] || set[i]->m_Permission == AccessPermission_NotPresent) {
+            set[i] = entry;  // Init entry
+            set[i]->m_Address = address;
+            set[i]->m_Permission = AccessPermission_Invalid;
+            DPRINTF(RubyCache, "Allocate clearing lock for addr: %x\n",
+                    address);
+            set[i]->m_locked = -1;
+            m_tag_index[address] = i;
+
+            m_replacementPolicy_ptr->
+                touch(cacheSet, i, g_eventQueue_ptr->getTime());
+            return;
+        }
+    }
+    panic("Allocate didn't find an available entry");
+}
+
+void
 CacheMemory::deallocate(const Address& address)
 {
     assert(address == line_address(address));