* VMArea: Made memory_type private and added setter and getter methods.

* Don't set the VMArea's memory type in arch_vm_set_memory_type(), but let the
  callers do that.
* vm_set_area_memory_type(): Does nothing, if the memory type doesn't change.



git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@36573 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/vm/VMArea.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2009, Ingo Weinhold, [email protected].
+ * Copyright 2009-2010, Ingo Weinhold, [email protected].
  * Copyright 2002-2009, Axel Dörfler, [email protected].
  * Distributed under the terms of the MIT License.
  *
@@ -10,6 +10,8 @@
 #define _KERNEL_VM_VM_AREA_H
 
 
+#include <vm_defs.h>
+
 #include <lock.h>
 #include <util/DoublyLinkedList.h>
 #include <util/SinglyLinkedList.h>
@@ -91,8 +93,11 @@ struct VMArea {
 	area_id					id;
 	uint32					protection;
 	uint16					wiring;
-	uint16					memory_type;
 
+private:
+	uint16					memory_type;	// >> shifted by MEMORY_TYPE_SHIFT
+
+public:
 	VMCache*				cache;
 	vint32					no_cache_change;
 	off_t					cache_offset;
@@ -108,6 +113,9 @@ struct VMArea {
 			addr_t				Base() const	{ return fBase; }
 			size_t				Size() const	{ return fSize; }
 
+	inline	uint32				MemoryType() const;
+	inline	void				SetMemoryType(uint32 memoryType);
+
 			bool				ContainsAddress(addr_t address) const
 									{ return address >= fBase
 										&& address <= fBase + (fSize - 1); }
@@ -204,4 +212,18 @@ private:
 };
 
 
+uint32
+VMArea::MemoryType() const
+{
+	return (uint32)memory_type << MEMORY_TYPE_SHIFT;
+}
+
+
+void
+VMArea::SetMemoryType(uint32 memoryType)
+{
+	memory_type = memoryType >> MEMORY_TYPE_SHIFT;
+}
+
+
 #endif	// _KERNEL_VM_VM_AREA_H

src/system/kernel/arch/x86/arch_vm.cpp

@@ -678,7 +678,7 @@ arch_vm_supports_protection(uint32 protection)
 void
 arch_vm_unset_memory_type(struct VMArea *area)
 {
-	if (area->memory_type == 0)
+	if (area->MemoryType() == 0)
 		return;
 
 	remove_memory_type_range(area->id);
@@ -686,9 +686,7 @@ arch_vm_unset_memory_type(struct VMArea *area)
 
 
 status_t
-arch_vm_set_memory_type(struct VMArea *area, addr_t physicalBase,
+arch_vm_set_memory_type(struct VMArea *area, addr_t physicalBase, uint32 type)
-	uint32 type)
 {
-	area->memory_type = type >> MEMORY_TYPE_SHIFT;
 	return add_memory_type_range(area->id, physicalBase, area->Size(), type);
 }

src/system/kernel/vm/vm.cpp

@@ -1444,6 +1444,8 @@ vm_map_physical_memory(team_id team, const char* name, void** _address,
 		if (memoryType == 0)
 			memoryType = B_MTR_UC;
 
+		area->SetMemoryType(memoryType);
+
 		status = arch_vm_set_memory_type(area, physicalAddress, memoryType);
 		if (status != B_OK)
 			delete_area(locker.AddressSpace(), area, false);
@@ -3038,7 +3040,7 @@ dump_area_struct(VMArea* area, bool mappings)
 	kprintf("size:\t\t0x%lx\n", area->Size());
 	kprintf("protection:\t0x%lx\n", area->protection);
 	kprintf("wiring:\t\t0x%x\n", area->wiring);
-	kprintf("memory_type:\t0x%x\n", area->memory_type);
+	kprintf("memory_type:\t%#" B_PRIx32 "\n", area->MemoryType());
 	kprintf("cache:\t\t%p\n", area->cache);
 	kprintf("cache_type:\t%s\n", cache_type_to_string(area->cache_type));
 	kprintf("cache_offset:\t0x%Lx\n", area->cache_offset);
@@ -4457,7 +4459,19 @@ vm_set_area_memory_type(area_id id, addr_t physicalBase, uint32 type)
 	if (status != B_OK)
 		return status;
 
-	return arch_vm_set_memory_type(area, physicalBase, type);
+	// nothing to do, if the type doesn't change
+	uint32 oldType = area->MemoryType();
+	if (type == oldType)
+		return B_OK;
+
+	// set the physical memory type
+	status_t error = arch_vm_set_memory_type(area, physicalBase, type);
+	if (error != B_OK)
+		return error;
+
+	area->SetMemoryType(type);
+	return B_OK;
+
 }