mem: adding a multi-level page table class

This patch defines a multi-level page table class that stores the page table in
system memory, consistent with ISA specifications. In this way, cpu models that
use the actual hardware to execute (e.g. KvmCPU), are able to traverse the page
table.

1 files changed, 15 insertions, 19 deletions

diff --git a/src/mem/page_table.cc b/src/mem/page_table.cc
index cb7ddfe4b..8770abf98 100644
--- a/src/mem/page_table.cc
+++ b/src/mem/page_table.cc
@@ -1,4 +1,5 @@
 /*
+ * Copyright (c) 2014 Advanced Micro Devices, Inc.
  * Copyright (c) 2003 The Regents of The University of Michigan
  * All rights reserved.
  *
@@ -32,7 +33,7 @@
 
 /**
  * @file
- * Definitions of page table.
+ * Definitions of functional page table.
  */
 #include <fstream>
 #include <map>
@@ -50,22 +51,17 @@
 using namespace std;
 using namespace TheISA;
 
-PageTable::PageTable(const std::string &__name, uint64_t _pid, Addr _pageSize)
-    : pageSize(_pageSize), offsetMask(mask(floorLog2(_pageSize))),
-      pid(_pid), _name(__name)
+FuncPageTable::FuncPageTable(const std::string &__name, uint64_t _pid, Addr _pageSize)
+        : PageTableBase(__name, _pid, _pageSize)
 {
-    assert(isPowerOf2(pageSize));
-    pTableCache[0].valid = false;
-    pTableCache[1].valid = false;
-    pTableCache[2].valid = false;
 }
 
-PageTable::~PageTable()
+FuncPageTable::~FuncPageTable()
 {
 }
 
 void
-PageTable::map(Addr vaddr, Addr paddr, int64_t size, bool clobber)
+FuncPageTable::map(Addr vaddr, Addr paddr, int64_t size, bool clobber)
 {
     // starting address must be page aligned
     assert(pageOffset(vaddr) == 0);
@@ -75,7 +71,7 @@ PageTable::map(Addr vaddr, Addr paddr, int64_t size, bool clobber)
     for (; size > 0; size -= pageSize, vaddr += pageSize, paddr += pageSize) {
         if (!clobber && (pTable.find(vaddr) != pTable.end())) {
             // already mapped
-            fatal("PageTable::allocate: address 0x%x already mapped", vaddr);
+            fatal("FuncPageTable::allocate: address 0x%x already mapped", vaddr);
         }
 
         pTable[vaddr] = TheISA::TlbEntry(pid, vaddr, paddr);
@@ -85,7 +81,7 @@ PageTable::map(Addr vaddr, Addr paddr, int64_t size, bool clobber)
 }
 
 void
-PageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
+FuncPageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
 {
     assert(pageOffset(vaddr) == 0);
     assert(pageOffset(new_vaddr) == 0);
@@ -105,7 +101,7 @@ PageTable::remap(Addr vaddr, int64_t size, Addr new_vaddr)
 }
 
 void
-PageTable::unmap(Addr vaddr, int64_t size)
+FuncPageTable::unmap(Addr vaddr, int64_t size)
 {
     assert(pageOffset(vaddr) == 0);
 
@@ -120,7 +116,7 @@ PageTable::unmap(Addr vaddr, int64_t size)
 }
 
 bool
-PageTable::isUnmapped(Addr vaddr, int64_t size)
+FuncPageTable::isUnmapped(Addr vaddr, int64_t size)
 {
     // starting address must be page aligned
     assert(pageOffset(vaddr) == 0);
@@ -135,7 +131,7 @@ PageTable::isUnmapped(Addr vaddr, int64_t size)
 }
 
 bool
-PageTable::lookup(Addr vaddr, TheISA::TlbEntry &entry)
+FuncPageTable::lookup(Addr vaddr, TheISA::TlbEntry &entry)
 {
     Addr page_addr = pageAlign(vaddr);
 
@@ -164,7 +160,7 @@ PageTable::lookup(Addr vaddr, TheISA::TlbEntry &entry)
 }
 
 bool
-PageTable::translate(Addr vaddr, Addr &paddr)
+PageTableBase::translate(Addr vaddr, Addr &paddr)
 {
     TheISA::TlbEntry entry;
     if (!lookup(vaddr, entry)) {
@@ -177,7 +173,7 @@ PageTable::translate(Addr vaddr, Addr &paddr)
 }
 
 Fault
-PageTable::translate(RequestPtr req)
+PageTableBase::translate(RequestPtr req)
 {
     Addr paddr;
     assert(pageAlign(req->getVaddr() + req->getSize() - 1)
@@ -194,7 +190,7 @@ PageTable::translate(RequestPtr req)
 }
 
 void
-PageTable::serialize(std::ostream &os)
+FuncPageTable::serialize(std::ostream &os)
 {
     paramOut(os, "ptable.size", pTable.size());
 
@@ -215,7 +211,7 @@ PageTable::serialize(std::ostream &os)
 }
 
 void
-PageTable::unserialize(Checkpoint *cp, const std::string &section)
+FuncPageTable::unserialize(Checkpoint *cp, const std::string &section)
 {
     int i = 0, count;
     paramIn(cp, section, "ptable.size", count);