sim, kvm: make KvmVM a System parameter

A KVM VM is typically a child of the System object already, but for
solving future issues with configuration graph resolution, the most
logical way to keep track of this object is for it to be an actual
parameter of the System object.

Change-Id: I965ded22203ff8667db9ca02de0042ff1c772220
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>

3 files changed, 30 insertions, 0 deletions

diff --git a/src/sim/System.py b/src/sim/System.py
index 34b1fd127..e3e42d862 100644
--- a/src/sim/System.py
+++ b/src/sim/System.py
@@ -29,6 +29,7 @@
 #          Rick Strong
 
 from m5.SimObject import SimObject
+from m5.defines import buildEnv
 from m5.params import *
 from m5.proxy import *
 
@@ -106,3 +107,6 @@ class System(MemObject):
     # Dynamic voltage and frequency handler for the system, disabled by default
     # Provide list of domains that need to be controlled by the handler
     dvfs_handler = DVFSHandler()
+
+    if buildEnv['USE_KVM']:
+        kvm_vm = Param.KvmVM(NULL, 'KVM VM (i.e., shared memory domain)')
diff --git a/src/sim/system.cc b/src/sim/system.cc
index 09be232a7..9315882b7 100644
--- a/src/sim/system.cc
+++ b/src/sim/system.cc
@@ -53,6 +53,10 @@
 #include "base/loader/symtab.hh"
 #include "base/str.hh"
 #include "base/trace.hh"
+#include "config/use_kvm.hh"
+#if USE_KVM
+#include "cpu/kvm/vm.hh"
+#endif
 #include "cpu/thread_context.hh"
 #include "debug/Loader.hh"
 #include "debug/WorkItems.hh"
@@ -90,6 +94,11 @@ System::System(Params *p)
       kernel(nullptr),
       loadAddrMask(p->load_addr_mask),
       loadAddrOffset(p->load_offset),
+#if USE_KVM
+      kvmVM(p->kvm_vm),
+#else
+      kvmVM(nullptr),
+#endif
       physmem(name() + ".physmem", p->memories, p->mmap_using_noreserve),
       memoryMode(p->mem_mode),
       _cacheLineSize(p->cache_line_size),
@@ -104,6 +113,12 @@ System::System(Params *p)
     // add self to global system list
     systemList.push_back(this);
 
+#if USE_KVM
+    if (kvmVM) {
+        kvmVM->setSystem(this);
+    }
+#endif
+
     if (FullSystem) {
         kernelSymtab = new SymbolTable;
         if (!debugSymbolTable)
diff --git a/src/sim/system.hh b/src/sim/system.hh
index 1bbd37d9d..c3667fe09 100644
--- a/src/sim/system.hh
+++ b/src/sim/system.hh
@@ -72,6 +72,7 @@
 
 class BaseRemoteGDB;
 class GDBListener;
+class KvmVM;
 class ObjectFile;
 class ThreadContext;
 
@@ -249,6 +250,14 @@ class System : public MemObject
     Addr loadAddrOffset;
 
   public:
+    /**
+     * Get a pointer to the Kernel Virtual Machine (KVM) SimObject,
+     * if present.
+     */
+    KvmVM* getKvmVM() {
+        return kvmVM;
+    }
+
     /** Get a pointer to access the physical memory of the system */
     PhysicalMemory& getPhysMem() { return physmem; }
 
@@ -289,6 +298,8 @@ class System : public MemObject
 
   protected:
 
+    KvmVM *const kvmVM;
+
     PhysicalMemory physmem;
 
     Enums::MemoryMode memoryMode;