Initial check in. Very preliminary and not really part of the kernel right now...

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@329 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/kernel/vm2/cacheManager.C

@@ -0,0 +1,54 @@
+#include <cacheManager.h>
+
+cacheManager::cacheManager(void) : area (NULL)
+{
+}
+
+void *cacheManager::findBlock(vnode *target,bool readOnly)
+	{
+	if (!cacheMembers.rock)
+		return NULL;
+	for (struct cacheMember *cur=((cacheMember *)cacheMembers.rock);cur;cur=((cacheMember *)cur->next))
+		{
+		if ((target==cur->vn) && (readOnly || (cur->vp->getProtection()>=writable)))
+			return (cur->vp->getStartAddress());
+		}
+	return NULL;
+	}
+
+void *cacheManager::createBlock(vnode *target,bool readOnly)
+{
+	bool foundSpot=false;
+	vpage *prev=NULL,*cur=NULL;
+	unsigned long begin=CACHE_BEGIN;
+	if (vpages.rock)
+		for (cur=((vpage *)(vpages.rock));!foundSpot && cur;cur=(vpage *)(cur->next))
+			if (cur->getStartAddress()!=(void *)begin)
+				foundSpot=true;
+			else // no joy
+				{
+				begin+=PAGE_SIZE;
+				prev=cur;
+				}
+	// Create a vnode here
+	vpage *newPage = new vpage(begin,*target,NULL,((readOnly)?readable:writable),NO_LOCK);
+	vpages.add(newPage); 
+	cacheMembers.add(newPage);
+	// return address from this vnode
+	return (void *)begin;
+
+}
+
+void *cacheManager::readBlock(vnode *target)
+{
+	void *destination=findBlock(target,true);
+	if (destination) return destination;
+	return createBlock(target,true);
+}
+
+void *cacheManager::writeBlock(vnode *target)
+{
+	void *destination=findBlock(target,false);
+	if (destination) return destination;
+	return createBlock(target,false);
+}