CACHE_DONT_LOCK_KERNEL_SPACE. If the former is given, the slab memory manager
does not wait when reserving memory or pages. The latter prevents area
operations. The new flags add a bit of flexibility. E.g. when allocating page
mapping objects for userland areas CACHE_DONT_WAIT_FOR_MEMORY is sufficient,
i.e. the allocation will succeed as long as pages are available.
git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@35246 a95241bf-73f2-0310-859d-f6bbb57e9c96