Changed the way the stores commit their memory: there is no special handling

for temporary memory anymore, it's the store's responsibility to do that
correctly now, and that functionality is reached via the vm_cache using
vm_cache_set_minimal_commitment().
Therefore, the vm_store commit() function now returns a status instead of
the size that could be commited.
Replaced the max_commit mechanism with one that cares about the available
memory, stores can reserve and unreserve such memory. The anonymous_commit()
will now fail in case it could not reserve the needed amount of memory.


git-svn-id: file:///srv/svn/repos/haiku/trunk/current@9777 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/kernel/vm_page.h

@@ -27,6 +27,10 @@ status_t vm_mark_page_inuse(addr_t page);
 status_t vm_mark_page_range_inuse(addr_t startPage, addr_t length);
 status_t vm_page_set_state(vm_page *page, int state);
 
+// get some data about the number of pages in the system
+addr_t vm_page_num_pages(void);
+addr_t vm_page_num_free_pages(void);
+
 vm_page *vm_page_allocate_page(int state);
 vm_page *vm_page_allocate_page_run(int state, addr_t length);
 vm_page *vm_page_allocate_specific_page(addr_t page_num, int state);