[Zion] Separate Memory "Views" to a separate MemoryObject.

zion/loader/init_loader.cpp

@@ -132,8 +132,8 @@ void WriteInitProgram(glcr::RefPtr<Port> port, glcr::String name, uint64_t id) {
 
 glcr::ErrorCode WritePciVmmo(glcr::RefPtr<Port> port, uint64_t id) {
   ASSIGN_OR_RETURN(PcieConfiguration config, GetPciExtendedConfiguration());
-  auto vmmo = glcr::MakeRefCounted<FixedMemoryObject>(config.base,
+  auto vmmo =
-                                                      config.offset, false);
+      glcr::MakeRefCounted<ViewMemoryObject>(config.base, config.offset);
 
   port->WriteKernel(id, MakeRefCounted<Capability>(vmmo));
 

zion/object/memory_object.cpp

@@ -72,18 +72,15 @@ uint64_t VariableMemoryObject::PageNumberToPhysAddr(uint64_t page_num) {
 }
 
 FixedMemoryObject::~FixedMemoryObject() {
-  if (should_free_) {
   phys_mem::FreePages(physical_addr_, num_pages());
-  }
 }
 
-glcr::ErrorOr<glcr::RefPtr<MemoryObject>> FixedMemoryObject::Duplicate(
+glcr::ErrorOr<glcr::RefPtr<MemoryObject>> ViewMemoryObject::Duplicate(
     uint64_t offset, uint64_t length) {
   if (offset + length > size()) {
     return glcr::INVALID_ARGUMENT;
   }
 
   return glcr::StaticCastRefPtr<MemoryObject>(
-      glcr::MakeRefCounted<FixedMemoryObject>(physical_addr_ + offset, length,
+      glcr::MakeRefCounted<ViewMemoryObject>(physical_addr_ + offset, length));
-                                              false));
 }

zion/object/memory_object.h

@@ -68,12 +68,37 @@ class VariableMemoryObject : public MemoryObject {
 class FixedMemoryObject : public MemoryObject {
  public:
   // FIXME: Validate that this is 4k aligned.
-  // Create a new class object for should free.
+  FixedMemoryObject(uint64_t physical_addr, uint64_t size)
-  FixedMemoryObject(uint64_t physical_addr, uint64_t size, bool should_free)
+      : size_(size), physical_addr_(physical_addr) {}
-      : size_(size), physical_addr_(physical_addr), should_free_(should_free) {}
 
   ~FixedMemoryObject() override;
 
+  virtual uint64_t size() override { return size_; }
+  virtual glcr::ErrorOr<glcr::RefPtr<MemoryObject>> Duplicate(
+      uint64_t offset, uint64_t length) override {
+    return glcr::UNIMPLEMENTED;
+  }
+
+ protected:
+  uint64_t PageNumberToPhysAddr(uint64_t page_num) override {
+    return physical_addr_ + (kPageSize * page_num);
+  }
+
+ private:
+  uint64_t size_;
+  uint64_t physical_addr_;
+};
+
+// Like a FixedMemoryObject except it doesn't release
+// it's pages when it is done. Should be used for things
+// like HBAs and the PCI config space.
+class ViewMemoryObject : public MemoryObject {
+ public:
+  ViewMemoryObject(uint64_t physical_addr, uint64_t size)
+      : size_(size), physical_addr_(physical_addr) {}
+
+  ~ViewMemoryObject(){};
+
   virtual uint64_t size() override { return size_; }
   virtual glcr::ErrorOr<glcr::RefPtr<MemoryObject>> Duplicate(
       uint64_t offset, uint64_t length) override;
@@ -86,5 +111,4 @@ class FixedMemoryObject : public MemoryObject {
  private:
   uint64_t size_;
   uint64_t physical_addr_;
-  bool should_free_;
 };

zion/syscall/memory_object.cpp

@@ -14,8 +14,7 @@ z_err_t MemoryObjectCreate(ZMemoryObjectCreateReq* req) {
 z_err_t MemoryObjectCreatePhysical(ZMemoryObjectCreatePhysicalReq* req) {
   auto& curr_proc = gScheduler->CurrentProcess();
   uint64_t paddr = req->paddr;
-  auto vmmo_ref =
+  auto vmmo_ref = glcr::MakeRefCounted<ViewMemoryObject>(paddr, req->size);
-      glcr::MakeRefCounted<FixedMemoryObject>(paddr, req->size, false);
   *req->vmmo_cap =
       curr_proc.AddNewCapability(StaticCastRefPtr<MemoryObject>(vmmo_ref));
   return glcr::OK;
@@ -25,8 +24,7 @@ z_err_t MemoryObjectCreateContiguous(ZMemoryObjectCreateContiguousReq* req) {
   auto& curr_proc = gScheduler->CurrentProcess();
   uint64_t num_pages = ((req->size - 1) / 0x1000) + 1;
   uint64_t paddr = phys_mem::AllocateContinuous(num_pages);
-  auto vmmo_ref =
+  auto vmmo_ref = glcr::MakeRefCounted<FixedMemoryObject>(paddr, req->size);
-      glcr::MakeRefCounted<FixedMemoryObject>(paddr, req->size, true);
   *req->vmmo_cap =
       curr_proc.AddNewCapability(StaticCastRefPtr<MemoryObject>(vmmo_ref));
   *req->paddr = paddr;