syscall-emul: Move memState into its own file

The Process class is full of implementation details and
structures related to SE Mode. This changeset factors out an
internal class from Process and moves it into a separate file.
The purpose behind doing this is to clean up the code and make
it a bit more modular.

Change-Id: Ic6941a1657751e8d51d5b6b1dcc04f1195884280
Reviewed-on: https://gem5-review.googlesource.com/2263
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Maintainer: Andreas Sandberg <andreas.sandberg@arm.com>

1 files changed, 15 insertions, 25 deletions

diff --git a/src/sim/process.cc b/src/sim/process.cc
index 7cfaf6530..e516e2a05 100644
--- a/src/sim/process.cc
+++ b/src/sim/process.cc
@@ -111,7 +111,6 @@ Process::Process(ProcessParams * params, ObjectFile * obj_file)
       _pid(params->pid), _ppid(params->ppid),
       _pgid(params->pgid), drivers(params->drivers),
       fds(make_shared<FDArray>(params->input, params->output, params->errout)),
-      maxStackSize(params->maxStackSize),
       childClearTID(0)
 {
     if (_pid >= System::maxPID)
@@ -136,7 +135,6 @@ Process::Process(ProcessParams * params, ObjectFile * obj_file)
     _tgid = params->pid;
 
     exitGroup = new bool();
-    memState = new MemState();
     sigchld = new bool();
 
     if (!debugSymbolTable) {
@@ -164,7 +162,6 @@ Process::clone(ThreadContext *otc, ThreadContext *ntc,
         np->pTable = pTable;
         ntc->getMemProxy().setPageTable(np->pTable);
 
-        delete np->memState;
         np->memState = memState;
     } else {
         /**
@@ -323,24 +320,28 @@ Process::replicatePage(Addr vaddr, Addr new_paddr, ThreadContext *old_tc,
 bool
 Process::fixupStackFault(Addr vaddr)
 {
+    Addr stack_min = memState->getStackMin();
+    Addr stack_base = memState->getStackBase();
+    Addr max_stack_size = memState->getMaxStackSize();
+
     // Check if this is already on the stack and there's just no page there
     // yet.
-    if (vaddr >= memState->stackMin && vaddr < memState->stackBase) {
+    if (vaddr >= stack_min && vaddr < stack_base) {
         allocateMem(roundDown(vaddr, PageBytes), PageBytes);
         return true;
     }
 
     // We've accessed the next page of the stack, so extend it to include
     // this address.
-    if (vaddr < memState->stackMin
-        && vaddr >= memState->stackBase - maxStackSize) {
-        while (vaddr < memState->stackMin) {
-            memState->stackMin -= TheISA::PageBytes;
-            if (memState->stackBase - memState->stackMin > maxStackSize)
+    if (vaddr < stack_min && vaddr >= stack_base - max_stack_size) {
+        while (vaddr < stack_min) {
+            stack_min -= TheISA::PageBytes;
+            if (stack_base - stack_min > max_stack_size)
                 fatal("Maximum stack size exceeded\n");
-            allocateMem(memState->stackMin, TheISA::PageBytes);
+            allocateMem(stack_min, TheISA::PageBytes);
             inform("Increasing stack size by one page.");
         };
+        memState->setStackMin(stack_min);
         return true;
     }
     return false;
@@ -349,12 +350,6 @@ Process::fixupStackFault(Addr vaddr)
 void
 Process::serialize(CheckpointOut &cp) const
 {
-    SERIALIZE_SCALAR(memState->brkPoint);
-    SERIALIZE_SCALAR(memState->stackBase);
-    SERIALIZE_SCALAR(memState->stackSize);
-    SERIALIZE_SCALAR(memState->stackMin);
-    SERIALIZE_SCALAR(memState->nextThreadStackBase);
-    SERIALIZE_SCALAR(memState->mmapEnd);
     pTable->serialize(cp);
     /**
      * Checkpoints for file descriptors currently do not work. Need to
@@ -372,12 +367,6 @@ Process::serialize(CheckpointOut &cp) const
 void
 Process::unserialize(CheckpointIn &cp)
 {
-    UNSERIALIZE_SCALAR(memState->brkPoint);
-    UNSERIALIZE_SCALAR(memState->stackBase);
-    UNSERIALIZE_SCALAR(memState->stackSize);
-    UNSERIALIZE_SCALAR(memState->stackMin);
-    UNSERIALIZE_SCALAR(memState->nextThreadStackBase);
-    UNSERIALIZE_SCALAR(memState->mmapEnd);
     pTable->unserialize(cp);
     /**
      * Checkpoints for file descriptors currently do not work. Need to
@@ -446,13 +435,14 @@ Process::updateBias()
 
     // We are allocating the memory area; set the bias to the lowest address
     // in the allocated memory region.
-    Addr *end = &memState->mmapEnd;
-    Addr ld_bias = mmapGrowsDown() ? *end - interp_mapsize : *end;
+    Addr mmap_end = memState->getMmapEnd();
+    Addr ld_bias = mmapGrowsDown() ? mmap_end - interp_mapsize : mmap_end;
 
     // Adjust the process mmap area to give the interpreter room; the real
     // execve system call would just invoke the kernel's internal mmap
     // functions to make these adjustments.
-    *end = mmapGrowsDown() ? ld_bias : *end + interp_mapsize;
+    mmap_end = mmapGrowsDown() ? ld_bias : mmap_end + interp_mapsize;
+    memState->setMmapEnd(mmap_end);
 
     interp->updateBias(ld_bias);
 }