MEM: Make port proxies use references rather than pointers

This patch is adding a clearer design intent to all objects that would
not be complete without a port proxy by making the proxies members
rathen than dynamically allocated. In essence, if NULL would not be a
valid value for the proxy, then we avoid using a pointer to make this
clear.

The same approach is used for the methods using these proxies, such as
loadSections, that now use references rather than pointers to better
reflect the fact that NULL would not be an acceptable value (in fact
the code would break and that is how this patch started out).

Overall the concept of "using a reference to express unconditional
composition where a NULL pointer is never valid" could be done on a
much broader scale throughout the code base, but for now it is only
done in the locations affected by the proxies.

11 files changed, 135 insertions, 153 deletions

diff --git a/src/arch/x86/bios/e820.cc b/src/arch/x86/bios/e820.cc
index 7564fcec7..c966916f5 100644
--- a/src/arch/x86/bios/e820.cc
+++ b/src/arch/x86/bios/e820.cc
@@ -39,21 +39,21 @@
 
 #include "arch/x86/bios/e820.hh"
 #include "arch/x86/isa_traits.hh"
-#include "mem/port.hh"
+#include "mem/port_proxy.hh"
 #include "sim/byteswap.hh"
 
 using namespace std;
 using namespace X86ISA;
 
 template<class T>
-void writeVal(T val, Port * port, Addr &addr)
+void writeVal(T val, PortProxy& proxy, Addr &addr)
 {
     T guestVal = htog(val);
-    port->writeBlob(addr, (uint8_t *)&guestVal, sizeof(T));
+    proxy.writeBlob(addr, (uint8_t *)&guestVal, sizeof(T));
     addr += sizeof(T);
 }
 
-void X86ISA::E820Table::writeTo(Port * port, Addr countAddr, Addr addr)
+void X86ISA::E820Table::writeTo(PortProxy& proxy, Addr countAddr, Addr addr)
 {
     uint8_t e820Nr = entries.size();
 
@@ -63,12 +63,12 @@ void X86ISA::E820Table::writeTo(Port * port, Addr countAddr, Addr addr)
 
     uint8_t guestE820Nr = htog(e820Nr);
 
-    port->writeBlob(countAddr, (uint8_t *)&guestE820Nr, sizeof(guestE820Nr));
+    proxy.writeBlob(countAddr, (uint8_t *)&guestE820Nr, sizeof(guestE820Nr));
 
     for (int i = 0; i < e820Nr; i++) {
-        writeVal(entries[i]->addr, port, addr);
-        writeVal(entries[i]->size, port, addr);
-        writeVal(entries[i]->type, port, addr);
+        writeVal(entries[i]->addr, proxy, addr);
+        writeVal(entries[i]->size, proxy, addr);
+        writeVal(entries[i]->type, proxy, addr);
     }
 }
 
diff --git a/src/arch/x86/bios/e820.hh b/src/arch/x86/bios/e820.hh
index cb8d5946c..b61708050 100644
--- a/src/arch/x86/bios/e820.hh
+++ b/src/arch/x86/bios/e820.hh
@@ -47,7 +47,7 @@
 #include "params/X86E820Table.hh"
 #include "sim/sim_object.hh"
 
-class Port;
+class PortProxy;
 
 namespace X86ISA
 {
@@ -75,7 +75,7 @@ namespace X86ISA
         E820Table(Params *p) : SimObject(p), entries(p->entries)
         {}
 
-        void writeTo(Port * port, Addr countAddr, Addr addr);
+        void writeTo(PortProxy& proxy, Addr countAddr, Addr addr);
     };
 };
 
diff --git a/src/arch/x86/bios/intelmp.cc b/src/arch/x86/bios/intelmp.cc
index 4c9c61adb..645c51b36 100644
--- a/src/arch/x86/bios/intelmp.cc
+++ b/src/arch/x86/bios/intelmp.cc
@@ -70,10 +70,10 @@ const char X86ISA::IntelMP::FloatingPointer::signature[] = "_MP_";
 
 template<class T>
 uint8_t
-writeOutField(PortProxy* proxy, Addr addr, T val)
+writeOutField(PortProxy& proxy, Addr addr, T val)
 {
     uint64_t guestVal = X86ISA::htog(val);
-    proxy->writeBlob(addr, (uint8_t *)(&guestVal), sizeof(T));
+    proxy.writeBlob(addr, (uint8_t *)(&guestVal), sizeof(T));
 
     uint8_t checkSum = 0;
     while(guestVal) {
@@ -84,7 +84,7 @@ writeOutField(PortProxy* proxy, Addr addr, T val)
 }
 
 uint8_t
-writeOutString(PortProxy* proxy, Addr addr, string str, int length)
+writeOutString(PortProxy& proxy, Addr addr, string str, int length)
 {
     char cleanedString[length + 1];
     cleanedString[length] = 0;
@@ -97,7 +97,7 @@ writeOutString(PortProxy* proxy, Addr addr, string str, int length)
         memcpy(cleanedString, str.c_str(), str.length());
         memset(cleanedString + str.length(), 0, length - str.length());
     }
-    proxy->writeBlob(addr, (uint8_t *)(&cleanedString), length);
+    proxy.writeBlob(addr, (uint8_t *)(&cleanedString), length);
 
     uint8_t checkSum = 0;
     for (int i = 0; i < length; i++)
@@ -107,7 +107,7 @@ writeOutString(PortProxy* proxy, Addr addr, string str, int length)
 }
 
 Addr
-X86ISA::IntelMP::FloatingPointer::writeOut(PortProxy* proxy, Addr addr)
+X86ISA::IntelMP::FloatingPointer::writeOut(PortProxy& proxy, Addr addr)
 {
     // Make sure that either a config table is present or a default
     // configuration was found but not both.
@@ -120,7 +120,7 @@ X86ISA::IntelMP::FloatingPointer::writeOut(PortProxy* proxy, Addr addr)
 
     uint8_t checkSum = 0;
 
-    proxy->writeBlob(addr, (uint8_t *)signature, 4);
+    proxy.writeBlob(addr, (uint8_t *)signature, 4);
     for (int i = 0; i < 4; i++)
         checkSum += signature[i];
 
@@ -128,20 +128,20 @@ X86ISA::IntelMP::FloatingPointer::writeOut(PortProxy* proxy, Addr addr)
 
     // The length of the structure in paragraphs, aka 16 byte chunks.
     uint8_t length = 1;
-    proxy->writeBlob(addr + 8, &length, 1);
+    proxy.writeBlob(addr + 8, &length, 1);
     checkSum += length;
 
-    proxy->writeBlob(addr + 9, &specRev, 1);
+    proxy.writeBlob(addr + 9, &specRev, 1);
     checkSum += specRev;
 
-    proxy->writeBlob(addr + 11, &defaultConfig, 1);
+    proxy.writeBlob(addr + 11, &defaultConfig, 1);
     checkSum += defaultConfig;
 
     uint32_t features2_5 = imcrPresent ? (1 << 7) : 0;
     checkSum += writeOutField(proxy, addr + 12, features2_5);
 
     checkSum = -checkSum;
-    proxy->writeBlob(addr + 10, &checkSum, 1);
+    proxy.writeBlob(addr + 10, &checkSum, 1);
 
     return 16;
 }
@@ -158,10 +158,10 @@ X86IntelMPFloatingPointerParams::create()
 }
 
 Addr
-X86ISA::IntelMP::BaseConfigEntry::writeOut(PortProxy* proxy,
+X86ISA::IntelMP::BaseConfigEntry::writeOut(PortProxy& proxy,
         Addr addr, uint8_t &checkSum)
 {
-    proxy->writeBlob(addr, &type, 1);
+    proxy.writeBlob(addr, &type, 1);
     checkSum += type;
     return 1;
 }
@@ -171,12 +171,12 @@ X86ISA::IntelMP::BaseConfigEntry::BaseConfigEntry(Params * p, uint8_t _type) :
 {}
 
 Addr
-X86ISA::IntelMP::ExtConfigEntry::writeOut(PortProxy* proxy,
+X86ISA::IntelMP::ExtConfigEntry::writeOut(PortProxy& proxy,
         Addr addr, uint8_t &checkSum)
 {
-    proxy->writeBlob(addr, &type, 1);
+    proxy.writeBlob(addr, &type, 1);
     checkSum += type;
-    proxy->writeBlob(addr + 1, &length, 1);
+    proxy.writeBlob(addr + 1, &length, 1);
     checkSum += length;
     return 1;
 }
@@ -189,17 +189,17 @@ X86ISA::IntelMP::ExtConfigEntry::ExtConfigEntry(Params * p,
 const char X86ISA::IntelMP::ConfigTable::signature[] = "PCMP";
 
 Addr
-X86ISA::IntelMP::ConfigTable::writeOut(PortProxy* proxy, Addr addr)
+X86ISA::IntelMP::ConfigTable::writeOut(PortProxy& proxy, Addr addr)
 {
     uint8_t checkSum = 0;
 
-    proxy->writeBlob(addr, (uint8_t *)signature, 4);
+    proxy.writeBlob(addr, (uint8_t *)signature, 4);
     for (int i = 0; i < 4; i++)
         checkSum += signature[i];
 
     // Base table length goes here but will be calculated later.
 
-    proxy->writeBlob(addr + 6, (uint8_t *)(&specRev), 1);
+    proxy.writeBlob(addr + 6, (uint8_t *)(&specRev), 1);
     checkSum += specRev;
 
     // The checksum goes here but is still being calculated.
@@ -213,7 +213,7 @@ X86ISA::IntelMP::ConfigTable::writeOut(PortProxy* proxy, Addr addr)
     checkSum += writeOutField(proxy, addr + 36, localApic);
 
     uint8_t reserved = 0;
-    proxy->writeBlob(addr + 43, &reserved, 1);
+    proxy.writeBlob(addr + 43, &reserved, 1);
     checkSum += reserved;
 
     vector<BaseConfigEntry *>::iterator baseEnt;
@@ -261,7 +261,7 @@ X86IntelMPConfigTableParams::create()
 
 Addr
 X86ISA::IntelMP::Processor::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     BaseConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 1, localApicID);
@@ -271,8 +271,8 @@ X86ISA::IntelMP::Processor::writeOut(
     checkSum += writeOutField(proxy, addr + 8, featureFlags);
 
     uint32_t reserved = 0;
-    proxy->writeBlob(addr + 12, (uint8_t *)(&reserved), 4);
-    proxy->writeBlob(addr + 16, (uint8_t *)(&reserved), 4);
+    proxy.writeBlob(addr + 12, (uint8_t *)(&reserved), 4);
+    proxy.writeBlob(addr + 16, (uint8_t *)(&reserved), 4);
     return 20;
 }
 
@@ -298,7 +298,7 @@ X86IntelMPProcessorParams::create()
 
 Addr
 X86ISA::IntelMP::Bus::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     BaseConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 1, busID);
@@ -318,7 +318,7 @@ X86IntelMPBusParams::create()
 
 Addr
 X86ISA::IntelMP::IOAPIC::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     BaseConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 1, id);
@@ -343,7 +343,7 @@ X86IntelMPIOAPICParams::create()
 
 Addr
 X86ISA::IntelMP::IntAssignment::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     BaseConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 1, interruptType);
@@ -381,7 +381,7 @@ X86IntelMPLocalIntAssignmentParams::create()
 
 Addr
 X86ISA::IntelMP::AddrSpaceMapping::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     ExtConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 2, busID);
@@ -405,7 +405,7 @@ X86IntelMPAddrSpaceMappingParams::create()
 
 Addr
 X86ISA::IntelMP::BusHierarchy::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     ExtConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 2, busID);
@@ -413,7 +413,7 @@ X86ISA::IntelMP::BusHierarchy::writeOut(
     checkSum += writeOutField(proxy, addr + 4, parentBus);
 
     uint32_t reserved = 0;
-    proxy->writeBlob(addr + 5, (uint8_t *)(&reserved), 3);
+    proxy.writeBlob(addr + 5, (uint8_t *)(&reserved), 3);
 
     return length;
 }
@@ -434,7 +434,7 @@ X86IntelMPBusHierarchyParams::create()
 
 Addr
 X86ISA::IntelMP::CompatAddrSpaceMod::writeOut(
-        PortProxy* proxy, Addr addr, uint8_t &checkSum)
+        PortProxy& proxy, Addr addr, uint8_t &checkSum)
 {
     ExtConfigEntry::writeOut(proxy, addr, checkSum);
     checkSum += writeOutField(proxy, addr + 2, busID);
diff --git a/src/arch/x86/bios/intelmp.hh b/src/arch/x86/bios/intelmp.hh
index 4b730ad4b..909f8ad79 100644
--- a/src/arch/x86/bios/intelmp.hh
+++ b/src/arch/x86/bios/intelmp.hh
@@ -93,7 +93,7 @@ class FloatingPointer : public SimObject
 
   public:
 
-    Addr writeOut(PortProxy* proxy, Addr addr);
+    Addr writeOut(PortProxy& proxy, Addr addr);
 
     Addr getTableAddr()
     {
@@ -117,7 +117,7 @@ class BaseConfigEntry : public SimObject
 
   public:
 
-    virtual Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    virtual Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     BaseConfigEntry(Params * p, uint8_t _type);
 };
@@ -132,7 +132,7 @@ class ExtConfigEntry : public SimObject
 
   public:
 
-    virtual Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    virtual Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     ExtConfigEntry(Params * p, uint8_t _type, uint8_t _length);
 };
@@ -155,7 +155,7 @@ class ConfigTable : public SimObject
     std::vector<ExtConfigEntry *> extEntries;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr);
+    Addr writeOut(PortProxy& proxy, Addr addr);
 
     ConfigTable(Params * p);
 };
@@ -172,7 +172,7 @@ class Processor : public BaseConfigEntry
     uint32_t featureFlags;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     Processor(Params * p);
 };
@@ -186,7 +186,7 @@ class Bus : public BaseConfigEntry
     std::string busType;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     Bus(Params * p);
 };
@@ -202,7 +202,7 @@ class IOAPIC : public BaseConfigEntry
     uint32_t address;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     IOAPIC(Params * p);
 };
@@ -221,7 +221,7 @@ class IntAssignment : public BaseConfigEntry
     uint8_t destApicIntIn;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     IntAssignment(X86IntelMPBaseConfigEntryParams * p,
             Enums::X86IntelMPInterruptType _interruptType,
@@ -269,7 +269,7 @@ class AddrSpaceMapping : public ExtConfigEntry
     uint64_t addrLength;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     AddrSpaceMapping(Params * p);
 };
@@ -284,7 +284,7 @@ class BusHierarchy : public ExtConfigEntry
     uint8_t parentBus;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     BusHierarchy(Params * p);
 };
@@ -299,7 +299,7 @@ class CompatAddrSpaceMod : public ExtConfigEntry
     uint32_t rangeList;
 
   public:
-    Addr writeOut(PortProxy* proxy, Addr addr, uint8_t &checkSum);
+    Addr writeOut(PortProxy& proxy, Addr addr, uint8_t &checkSum);
 
     CompatAddrSpaceMod(Params * p);
 };
diff --git a/src/arch/x86/bios/smbios.cc b/src/arch/x86/bios/smbios.cc
index a85ece1ec..9072664bf 100644
--- a/src/arch/x86/bios/smbios.cc
+++ b/src/arch/x86/bios/smbios.cc
@@ -74,15 +74,15 @@ composeBitVector(T vec)
 }
 
 uint16_t
-X86ISA::SMBios::SMBiosStructure::writeOut(PortProxy* proxy, Addr addr)
+X86ISA::SMBios::SMBiosStructure::writeOut(PortProxy& proxy, Addr addr)
 {
-    proxy->writeBlob(addr, (uint8_t *)(&type), 1);
+    proxy.writeBlob(addr, (uint8_t *)(&type), 1);
 
     uint8_t length = getLength();
-    proxy->writeBlob(addr + 1, (uint8_t *)(&length), 1);
+    proxy.writeBlob(addr + 1, (uint8_t *)(&length), 1);
 
     uint16_t handleGuest = X86ISA::htog(handle);
-    proxy->writeBlob(addr + 2, (uint8_t *)(&handleGuest), 2);
+    proxy.writeBlob(addr + 2, (uint8_t *)(&handleGuest), 2);
 
     return length + getStringLength();
 }
@@ -93,7 +93,7 @@ X86ISA::SMBios::SMBiosStructure::SMBiosStructure(Params * p, uint8_t _type) :
 
 void
 X86ISA::SMBios::SMBiosStructure::writeOutStrings(
-        PortProxy* proxy, Addr addr)
+        PortProxy& proxy, Addr addr)
 {
     std::vector<std::string>::iterator it;
     Addr offset = 0;
@@ -103,16 +103,16 @@ X86ISA::SMBios::SMBiosStructure::writeOutStrings(
     // If there are string fields but none of them are used, that's a
     // special case which is handled by this if.
     if (strings.size() == 0 && stringFields) {
-        proxy->writeBlob(addr + offset, (uint8_t *)(&nullTerminator), 1);
+        proxy.writeBlob(addr + offset, (uint8_t *)(&nullTerminator), 1);
         offset++;
     } else {
         for (it = strings.begin(); it != strings.end(); it++) {
-            proxy->writeBlob(addr + offset,
+            proxy.writeBlob(addr + offset,
                     (uint8_t *)it->c_str(), it->length() + 1);
             offset += it->length() + 1;
         }
     }
-    proxy->writeBlob(addr + offset, (uint8_t *)(&nullTerminator), 1);
+    proxy.writeBlob(addr + offset, (uint8_t *)(&nullTerminator), 1);
 }
 
 int
@@ -172,30 +172,30 @@ X86ISA::SMBios::BiosInformation::BiosInformation(Params * p) :
     }
 
 uint16_t
-X86ISA::SMBios::BiosInformation::writeOut(PortProxy* proxy, Addr addr)
+X86ISA::SMBios::BiosInformation::writeOut(PortProxy& proxy, Addr addr)
 {
     uint8_t size = SMBiosStructure::writeOut(proxy, addr);
 
-    proxy->writeBlob(addr + 0x4, (uint8_t *)(&vendor), 1);
-    proxy->writeBlob(addr + 0x5, (uint8_t *)(&version), 1);
+    proxy.writeBlob(addr + 0x4, (uint8_t *)(&vendor), 1);
+    proxy.writeBlob(addr + 0x5, (uint8_t *)(&version), 1);
 
     uint16_t startingAddrSegmentGuest = X86ISA::htog(startingAddrSegment);
-    proxy->writeBlob(addr + 0x6, (uint8_t *)(&startingAddrSegmentGuest), 2);
+    proxy.writeBlob(addr + 0x6, (uint8_t *)(&startingAddrSegmentGuest), 2);
 
-    proxy->writeBlob(addr + 0x8, (uint8_t *)(&releaseDate), 1);
-    proxy->writeBlob(addr + 0x9, (uint8_t *)(&romSize), 1);
+    proxy.writeBlob(addr + 0x8, (uint8_t *)(&releaseDate), 1);
+    proxy.writeBlob(addr + 0x9, (uint8_t *)(&romSize), 1);
 
     uint64_t characteristicsGuest = X86ISA::htog(characteristics);
-    proxy->writeBlob(addr + 0xA, (uint8_t *)(&characteristicsGuest), 8);
+    proxy.writeBlob(addr + 0xA, (uint8_t *)(&characteristicsGuest), 8);
 
     uint16_t characteristicExtBytesGuest =
         X86ISA::htog(characteristicExtBytes);
-    proxy->writeBlob(addr + 0x12, (uint8_t *)(&characteristicExtBytesGuest), 2);
+    proxy.writeBlob(addr + 0x12, (uint8_t *)(&characteristicExtBytesGuest), 2);
 
-    proxy->writeBlob(addr + 0x14, (uint8_t *)(&majorVer), 1);
-    proxy->writeBlob(addr + 0x15, (uint8_t *)(&minorVer), 1);
-    proxy->writeBlob(addr + 0x16, (uint8_t *)(&embContFirmwareMajor), 1);
-    proxy->writeBlob(addr + 0x17, (uint8_t *)(&embContFirmwareMinor), 1);
+    proxy.writeBlob(addr + 0x14, (uint8_t *)(&majorVer), 1);
+    proxy.writeBlob(addr + 0x15, (uint8_t *)(&minorVer), 1);
+    proxy.writeBlob(addr + 0x16, (uint8_t *)(&embContFirmwareMajor), 1);
+    proxy.writeBlob(addr + 0x17, (uint8_t *)(&embContFirmwareMinor), 1);
 
     writeOutStrings(proxy, addr + getLength());
 
@@ -214,7 +214,7 @@ X86ISA::SMBios::SMBiosTable::SMBiosTable(Params * p) :
 }
 
 void
-X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
+X86ISA::SMBios::SMBiosTable::writeOut(PortProxy& proxy, Addr addr,
         Addr &headerSize, Addr &structSize)
 {
     headerSize = 0x1F;
@@ -224,26 +224,26 @@ X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
      */
     uint8_t mainChecksum = 0;
 
-    proxy->writeBlob(addr, (uint8_t *)smbiosHeader.anchorString, 4);
+    proxy.writeBlob(addr, (uint8_t *)smbiosHeader.anchorString, 4);
     for (int i = 0; i < 4; i++)
         mainChecksum += smbiosHeader.anchorString[i];
 
     // The checksum goes here, but we're figuring it out as we go.
 
-    proxy->writeBlob(addr + 0x5,
+    proxy.writeBlob(addr + 0x5,
             (uint8_t *)(&smbiosHeader.entryPointLength), 1);
     mainChecksum += smbiosHeader.entryPointLength;
-    proxy->writeBlob(addr + 0x6,
+    proxy.writeBlob(addr + 0x6,
             (uint8_t *)(&smbiosHeader.majorVersion), 1);
     mainChecksum += smbiosHeader.majorVersion;
-    proxy->writeBlob(addr + 0x7,
+    proxy.writeBlob(addr + 0x7,
             (uint8_t *)(&smbiosHeader.minorVersion), 1);
     mainChecksum += smbiosHeader.minorVersion;
     // Maximum structure size goes here, but we'll figure it out later.
-    proxy->writeBlob(addr + 0xA,
+    proxy.writeBlob(addr + 0xA,
             (uint8_t *)(&smbiosHeader.entryPointRevision), 1);
     mainChecksum += smbiosHeader.entryPointRevision;
-    proxy->writeBlob(addr + 0xB,
+    proxy.writeBlob(addr + 0xB,
             (uint8_t *)(&smbiosHeader.formattedArea), 5);
     for (int i = 0; i < 5; i++)
         mainChecksum += smbiosHeader.formattedArea[i];
@@ -253,7 +253,7 @@ X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
      */
     uint8_t intChecksum = 0;
 
-    proxy->writeBlob(addr + 0x10,
+    proxy.writeBlob(addr + 0x10,
             (uint8_t *)smbiosHeader.intermediateHeader.anchorString, 5);
     for (int i = 0; i < 5; i++)
         intChecksum += smbiosHeader.intermediateHeader.anchorString[i];
@@ -263,20 +263,20 @@ X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
 
     uint32_t tableAddrGuest =
         X86ISA::htog(smbiosHeader.intermediateHeader.tableAddr);
-    proxy->writeBlob(addr + 0x18, (uint8_t *)(&tableAddrGuest), 4);
+    proxy.writeBlob(addr + 0x18, (uint8_t *)(&tableAddrGuest), 4);
     for (int i = 0; i < 4; i++) {
         intChecksum += tableAddrGuest;
         tableAddrGuest >>= 8;
     }
 
     uint16_t numStructs = X86ISA::gtoh(structures.size());
-    proxy->writeBlob(addr + 0x1C, (uint8_t *)(&numStructs), 2);
+    proxy.writeBlob(addr + 0x1C, (uint8_t *)(&numStructs), 2);
     for (int i = 0; i < 2; i++) {
         intChecksum += numStructs;
         numStructs >>= 8;
     }
 
-    proxy->writeBlob(addr + 0x1E,
+    proxy.writeBlob(addr + 0x1E,
             (uint8_t *)(&smbiosHeader.intermediateHeader.smbiosBCDRevision),
             1);
     intChecksum += smbiosHeader.intermediateHeader.smbiosBCDRevision;
@@ -303,7 +303,7 @@ X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
      */
 
     maxSize = X86ISA::htog(maxSize);
-    proxy->writeBlob(addr + 0x8, (uint8_t *)(&maxSize), 2);
+    proxy.writeBlob(addr + 0x8, (uint8_t *)(&maxSize), 2);
     for (int i = 0; i < 2; i++) {
         mainChecksum += maxSize;
         maxSize >>= 8;
@@ -311,7 +311,7 @@ X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
 
     // Set the checksum
     mainChecksum = -mainChecksum;
-    proxy->writeBlob(addr + 0x4, (uint8_t *)(&mainChecksum), 1);
+    proxy.writeBlob(addr + 0x4, (uint8_t *)(&mainChecksum), 1);
 
     /*
      * Intermediate header
@@ -319,14 +319,14 @@ X86ISA::SMBios::SMBiosTable::writeOut(PortProxy* proxy, Addr addr,
 
     uint16_t tableSize = offset;
     tableSize = X86ISA::htog(tableSize);
-    proxy->writeBlob(addr + 0x16, (uint8_t *)(&tableSize), 2);
+    proxy.writeBlob(addr + 0x16, (uint8_t *)(&tableSize), 2);
     for (int i = 0; i < 2; i++) {
         intChecksum += tableSize;
         tableSize >>= 8;
     }
 
     intChecksum = -intChecksum;
-    proxy->writeBlob(addr + 0x15, (uint8_t *)(&intChecksum), 1);
+    proxy.writeBlob(addr + 0x15, (uint8_t *)(&intChecksum), 1);
 }
 
 X86ISA::SMBios::BiosInformation *
diff --git a/src/arch/x86/bios/smbios.hh b/src/arch/x86/bios/smbios.hh
index 805b03fbb..4b0a61190 100644
--- a/src/arch/x86/bios/smbios.hh
+++ b/src/arch/x86/bios/smbios.hh
@@ -89,7 +89,7 @@ class SMBiosStructure : public SimObject
         return 4;
     }
 
-    virtual uint16_t writeOut(PortProxy* proxy, Addr addr);
+    virtual uint16_t writeOut(PortProxy& proxy, Addr addr);
 
   protected:
     bool stringFields;
@@ -98,7 +98,7 @@ class SMBiosStructure : public SimObject
 
     std::vector<std::string> strings;
 
-    void writeOutStrings(PortProxy* proxy, Addr addr);
+    void writeOutStrings(PortProxy& proxy, Addr addr);
 
     int getStringLength();
 
@@ -145,7 +145,7 @@ class BiosInformation : public SMBiosStructure
     BiosInformation(Params * p);
 
     uint8_t getLength() { return 0x18; }
-    uint16_t writeOut(PortProxy* proxy, Addr addr);
+    uint16_t writeOut(PortProxy& proxy, Addr addr);
 };
 
 class SMBiosTable : public SimObject
@@ -223,7 +223,7 @@ class SMBiosTable : public SimObject
         smbiosHeader.intermediateHeader.tableAddr = addr;
     }
 
-    void writeOut(PortProxy* proxy, Addr addr,
+    void writeOut(PortProxy& proxy, Addr addr,
             Addr &headerSize, Addr &structSize);
 };
 
diff --git a/src/arch/x86/linux/syscalls.cc b/src/arch/x86/linux/syscalls.cc
index c6faf391b..b016a380a 100644
--- a/src/arch/x86/linux/syscalls.cc
+++ b/src/arch/x86/linux/syscalls.cc
@@ -81,7 +81,7 @@ archPrctlFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
     int code = process->getSyscallArg(tc, index);
     uint64_t addr = process->getSyscallArg(tc, index);
     uint64_t fsBase, gsBase;
-    SETranslatingPortProxy* p = tc->getMemProxy();
+    SETranslatingPortProxy &p = tc->getMemProxy();
     switch(code)
     {
       //Each of these valid options should actually check addr.
@@ -91,7 +91,7 @@ archPrctlFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
         return 0;
       case GetFS:
         fsBase = tc->readMiscRegNoEffect(MISCREG_FS_BASE);
-        p->write(addr, fsBase);
+        p.write(addr, fsBase);
         return 0;
       case SetGS:
         tc->setMiscRegNoEffect(MISCREG_GS_BASE, addr);
@@ -99,7 +99,7 @@ archPrctlFunc(SyscallDesc *desc, int callnum, LiveProcess *process,
         return 0;
       case GetGS:
         gsBase = tc->readMiscRegNoEffect(MISCREG_GS_BASE);
-        p->write(addr, gsBase);
+        p.write(addr, gsBase);
         return 0;
       default:
         return -EINVAL;
diff --git a/src/arch/x86/linux/system.cc b/src/arch/x86/linux/system.cc
index a933868d1..f473af40e 100644
--- a/src/arch/x86/linux/system.cc
+++ b/src/arch/x86/linux/system.cc
@@ -67,9 +67,6 @@ LinuxX86System::initState()
     // The location of the real mode data structure.
     const Addr realModeData = 0x90200;
 
-    // A port proxy to write to memory.
-    PortProxy* physProxy = threadContexts[0]->getPhysProxy();
-
     /*
      * Deal with the command line stuff.
      */
@@ -82,15 +79,15 @@ LinuxX86System::initState()
     if (commandLine.length() + 1 > realModeData - commandLineBuff)
         panic("Command line \"%s\" is longer than %d characters.\n",
                 commandLine, realModeData - commandLineBuff - 1);
-    physProxy->writeBlob(commandLineBuff,
-            (uint8_t *)commandLine.c_str(), commandLine.length() + 1);
+    physProxy.writeBlob(commandLineBuff, (uint8_t *)commandLine.c_str(),
+                        commandLine.length() + 1);
 
     // Generate a pointer of the right size and endianness to put into
     // commandLinePointer.
     uint32_t guestCommandLineBuff =
         X86ISA::htog((uint32_t)commandLineBuff);
-    physProxy->writeBlob(commandLinePointer,
-            (uint8_t *)&guestCommandLineBuff, sizeof(guestCommandLineBuff));
+    physProxy.writeBlob(commandLinePointer, (uint8_t *)&guestCommandLineBuff,
+                        sizeof(guestCommandLineBuff));
 
     /*
      * Screen Info.
@@ -127,7 +124,7 @@ LinuxX86System::initState()
     // A pointer to the buffer for E820 entries.
     const Addr e820MapPointer = realModeData + 0x2d0;
 
-    e820Table->writeTo(getSystemPort(), e820MapNrPointer, e820MapPointer);
+    e820Table->writeTo(physProxy, e820MapNrPointer, e820MapPointer);
 
     /*
      * Pass the location of the real mode data structure to the kernel
diff --git a/src/arch/x86/process.cc b/src/arch/x86/process.cc
index 32fc8ca70..088a0661c 100644
--- a/src/arch/x86/process.cc
+++ b/src/arch/x86/process.cc
@@ -172,7 +172,7 @@ X86_64LiveProcess::initState()
         0x0f,0x05,                             // syscall
         0xc3                                   // retq
     };
-    initVirtMem->writeBlob(vsyscallPage.base + vsyscallPage.vtimeOffset,
+    initVirtMem.writeBlob(vsyscallPage.base + vsyscallPage.vtimeOffset,
             vtimeBlob, sizeof(vtimeBlob));
 
     uint8_t vgettimeofdayBlob[] = {
@@ -180,7 +180,7 @@ X86_64LiveProcess::initState()
         0x0f,0x05,                             // syscall
         0xc3                                   // retq
     };
-    initVirtMem->writeBlob(vsyscallPage.base + vsyscallPage.vgettimeofdayOffset,
+    initVirtMem.writeBlob(vsyscallPage.base + vsyscallPage.vgettimeofdayOffset,
             vgettimeofdayBlob, sizeof(vgettimeofdayBlob));
 
     for (int i = 0; i < contextIds.size(); i++) {
@@ -269,7 +269,7 @@ I386LiveProcess::initState()
     assert(_gdtSize % sizeof(zero) == 0);
     for (Addr gdtCurrent = _gdtStart;
             gdtCurrent < _gdtStart + _gdtSize; gdtCurrent += sizeof(zero)) {
-        initVirtMem->write(gdtCurrent, zero);
+        initVirtMem.write(gdtCurrent, zero);
     }
 
     // Set up the vsyscall page for this process.
@@ -281,7 +281,7 @@ I386LiveProcess::initState()
         0x89, 0xe5, // mov %esp, %ebp
         0x0f, 0x34  // sysenter
     };
-    initVirtMem->writeBlob(vsyscallPage.base + vsyscallPage.vsyscallOffset,
+    initVirtMem.writeBlob(vsyscallPage.base + vsyscallPage.vsyscallOffset,
             vsyscallBlob, sizeof(vsyscallBlob));
 
     uint8_t vsysexitBlob[] = {
@@ -290,7 +290,7 @@ I386LiveProcess::initState()
         0x59,       // pop %ecx
         0xc3        // ret
     };
-    initVirtMem->writeBlob(vsyscallPage.base + vsyscallPage.vsysexitOffset,
+    initVirtMem.writeBlob(vsyscallPage.base + vsyscallPage.vsysexitOffset,
             vsysexitBlob, sizeof(vsysexitBlob));
 
     for (int i = 0; i < contextIds.size(); i++) {
@@ -608,11 +608,11 @@ X86LiveProcess::argsInit(int pageSize,
 
     //Write out the sentry void *
     IntType sentry_NULL = 0;
-    initVirtMem->writeBlob(sentry_base,
+    initVirtMem.writeBlob(sentry_base,
             (uint8_t*)&sentry_NULL, sentry_size);
 
     //Write the file name
-    initVirtMem->writeString(file_name_base, filename.c_str());
+    initVirtMem.writeString(file_name_base, filename.c_str());
 
     //Fix up the aux vectors which point to data
     assert(auxv[auxv.size() - 3].a_type == M5_AT_RANDOM);
@@ -625,22 +625,22 @@ X86LiveProcess::argsInit(int pageSize,
     //Copy the aux stuff
     for(int x = 0; x < auxv.size(); x++)
     {
-        initVirtMem->writeBlob(auxv_array_base + x * 2 * intSize,
+        initVirtMem.writeBlob(auxv_array_base + x * 2 * intSize,
                 (uint8_t*)&(auxv[x].a_type), intSize);
-        initVirtMem->writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
+        initVirtMem.writeBlob(auxv_array_base + (x * 2 + 1) * intSize,
                 (uint8_t*)&(auxv[x].a_val), intSize);
     }
     //Write out the terminating zeroed auxilliary vector
     const uint64_t zero = 0;
-    initVirtMem->writeBlob(auxv_array_base + 2 * intSize * auxv.size(),
+    initVirtMem.writeBlob(auxv_array_base + 2 * intSize * auxv.size(),
             (uint8_t*)&zero, 2 * intSize);
 
-    initVirtMem->writeString(aux_data_base, platform.c_str());
+    initVirtMem.writeString(aux_data_base, platform.c_str());
 
     copyStringArray(envp, envp_array_base, env_data_base, initVirtMem);
     copyStringArray(argv, argv_array_base, arg_data_base, initVirtMem);
 
-    initVirtMem->writeBlob(argc_base, (uint8_t*)&guestArgc, intSize);
+    initVirtMem.writeBlob(argc_base, (uint8_t*)&guestArgc, intSize);
 
     ThreadContext *tc = system->getThreadContext(contextIds[0]);
     //Set the stack pointer register
diff --git a/src/arch/x86/stacktrace.cc b/src/arch/x86/stacktrace.cc
index e3d30d5cd..636f74123 100644
--- a/src/arch/x86/stacktrace.cc
+++ b/src/arch/x86/stacktrace.cc
@@ -48,29 +48,27 @@ namespace X86ISA
     {
         Addr addr = 0;
 
-        FSTranslatingPortProxy* vp;
-
-        vp = tc->getVirtProxy();
+        FSTranslatingPortProxy &vp = tc->getVirtProxy();
 
         if (!tc->getSystemPtr()->kernelSymtab->findAddress("thread_info_size", addr))
             panic("thread info not compiled into kernel\n");
-        thread_info_size = vp->readGtoH<int32_t>(addr);
+        thread_info_size = vp.readGtoH<int32_t>(addr);
 
         if (!tc->getSystemPtr()->kernelSymtab->findAddress("task_struct_size", addr))
             panic("thread info not compiled into kernel\n");
-        task_struct_size = vp->readGtoH<int32_t>(addr);
+        task_struct_size = vp.readGtoH<int32_t>(addr);
 
         if (!tc->getSystemPtr()->kernelSymtab->findAddress("thread_info_task", addr))
             panic("thread info not compiled into kernel\n");
-        task_off = vp->readGtoH<int32_t>(addr);
+        task_off = vp.readGtoH<int32_t>(addr);
 
         if (!tc->getSystemPtr()->kernelSymtab->findAddress("task_struct_pid", addr))
             panic("thread info not compiled into kernel\n");
-        pid_off = vp->readGtoH<int32_t>(addr);
+        pid_off = vp.readGtoH<int32_t>(addr);
 
         if (!tc->getSystemPtr()->kernelSymtab->findAddress("task_struct_comm", addr))
             panic("thread info not compiled into kernel\n");
-        name_off = vp->readGtoH<int32_t>(addr);
+        name_off = vp.readGtoH<int32_t>(addr);
     }
 
     Addr
@@ -82,10 +80,8 @@ namespace X86ISA
 
         Addr tsk;
 
-        FSTranslatingPortProxy* vp;
-
-        vp = tc->getVirtProxy();
-        tsk = vp->readGtoH<Addr>(base + task_off);
+        FSTranslatingPortProxy &vp = tc->getVirtProxy();
+        tsk = vp.readGtoH<Addr>(base + task_off);
 
         return tsk;
     }
@@ -99,10 +95,8 @@ namespace X86ISA
 
         uint16_t pd;
 
-        FSTranslatingPortProxy* vp;
-
-        vp = tc->getVirtProxy();
-        pd = vp->readGtoH<uint16_t>(task + pid_off);
+        FSTranslatingPortProxy &vp = tc->getVirtProxy();
+        pd = vp.readGtoH<uint16_t>(task + pid_off);
 
         return pd;
     }
diff --git a/src/arch/x86/system.cc b/src/arch/x86/system.cc
index ca13fd5ce..effe1e994 100644
--- a/src/arch/x86/system.cc
+++ b/src/arch/x86/system.cc
@@ -138,17 +138,14 @@ X86System::initState()
     const int PDPTBits = 9;
     const int PDTBits = 9;
 
-    // Get a port proxy to write the page tables and descriptor tables.
-    PortProxy* physProxy = tc->getPhysProxy();
-
     /*
      * Set up the gdt.
      */
     uint8_t numGDTEntries = 0;
     // Place holder at selector 0
     uint64_t nullDescriptor = 0;
-    physProxy->writeBlob(GDTBase + numGDTEntries * 8,
-            (uint8_t *)(&nullDescriptor), 8);
+    physProxy.writeBlob(GDTBase + numGDTEntries * 8,
+                        (uint8_t *)(&nullDescriptor), 8);
     numGDTEntries++;
 
     //64 bit code segment
@@ -169,8 +166,8 @@ X86System::initState()
     //it's beginning in memory and it's actual data, we'll use an
     //intermediary.
     uint64_t csDescVal = csDesc;
-    physProxy->writeBlob(GDTBase + numGDTEntries * 8,
-            (uint8_t *)(&csDescVal), 8);
+    physProxy.writeBlob(GDTBase + numGDTEntries * 8,
+                        (uint8_t *)(&csDescVal), 8);
 
     numGDTEntries++;
 
@@ -192,8 +189,8 @@ X86System::initState()
     dsDesc.limitHigh = 0xF;
     dsDesc.limitLow = 0xFF;
     uint64_t dsDescVal = dsDesc;
-    physProxy->writeBlob(GDTBase + numGDTEntries * 8,
-            (uint8_t *)(&dsDescVal), 8);
+    physProxy.writeBlob(GDTBase + numGDTEntries * 8,
+                        (uint8_t *)(&dsDescVal), 8);
 
     numGDTEntries++;
 
@@ -220,8 +217,8 @@ X86System::initState()
     tssDesc.limitHigh = 0xF;
     tssDesc.limitLow = 0xFF;
     uint64_t tssDescVal = tssDesc;
-    physProxy->writeBlob(GDTBase + numGDTEntries * 8,
-            (uint8_t *)(&tssDescVal), 8);
+    physProxy.writeBlob(GDTBase + numGDTEntries * 8,
+                        (uint8_t *)(&tssDescVal), 8);
 
     numGDTEntries++;
 
@@ -250,25 +247,25 @@ X86System::initState()
     // read/write, user, not present
     uint64_t pml4e = X86ISA::htog(0x6);
     for (int offset = 0; offset < (1 << PML4Bits) * 8; offset += 8) {
-        physProxy->writeBlob(PageMapLevel4 + offset, (uint8_t *)(&pml4e), 8);
+        physProxy.writeBlob(PageMapLevel4 + offset, (uint8_t *)(&pml4e), 8);
     }
     // Point to the only PDPT
     pml4e = X86ISA::htog(0x7 | PageDirPtrTable);
-    physProxy->writeBlob(PageMapLevel4, (uint8_t *)(&pml4e), 8);
+    physProxy.writeBlob(PageMapLevel4, (uint8_t *)(&pml4e), 8);
 
     // Page Directory Pointer Table
 
     // read/write, user, not present
     uint64_t pdpe = X86ISA::htog(0x6);
     for (int offset = 0; offset < (1 << PDPTBits) * 8; offset += 8) {
-        physProxy->writeBlob(PageDirPtrTable + offset,
-                (uint8_t *)(&pdpe), 8);
+        physProxy.writeBlob(PageDirPtrTable + offset,
+                            (uint8_t *)(&pdpe), 8);
     }
     // Point to the PDTs
     for (int table = 0; table < NumPDTs; table++) {
         pdpe = X86ISA::htog(0x7 | PageDirTable[table]);
-        physProxy->writeBlob(PageDirPtrTable + table * 8,
-                (uint8_t *)(&pdpe), 8);
+        physProxy.writeBlob(PageDirPtrTable + table * 8,
+                            (uint8_t *)(&pdpe), 8);
     }
 
     // Page Directory Tables
@@ -279,8 +276,8 @@ X86System::initState()
         for (int offset = 0; offset < (1 << PDTBits) * 8; offset += 8) {
             // read/write, user, present, 4MB
             uint64_t pdte = X86ISA::htog(0x87 | base);
-            physProxy->writeBlob(PageDirTable[table] + offset,
-                    (uint8_t *)(&pdte), 8);
+            physProxy.writeBlob(PageDirTable[table] + offset,
+                                (uint8_t *)(&pdte), 8);
             base += pageSize;
         }
     }
@@ -342,9 +339,6 @@ void
 X86System::writeOutSMBiosTable(Addr header,
         Addr &headerSize, Addr &structSize, Addr table)
 {
-    // Get a port proxy to write the table and header to memory.
-    PortProxy* physProxy = threadContexts[0]->getPhysProxy();
-
     // If the table location isn't specified, just put it after the header.
     // The header size as of the 2.5 SMBios specification is 0x1F bytes
     if (!table)
@@ -363,9 +357,6 @@ void
 X86System::writeOutMPTable(Addr fp,
         Addr &fpSize, Addr &tableSize, Addr table)
 {
-    // Get a port proxy to write the table and header to memory.
-    PortProxy* physProxy = threadContexts[0]->getPhysProxy();
-
     // If the table location isn't specified and it exists, just put
     // it after the floating pointer. The fp size as of the 1.4 Intel MP
     // specification is 0x10 bytes.