Contexts, surfaces and streams allocate persistent kernel memory as the
direct result of user-space requests. Make sure this memory is
accounted as graphics memory, to avoid DOS vulnerabilities.
Also take the TTM read lock around resource creation to block
switched-out dri clients from allocating resources.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com> Reviewed-by: Jakob Bornecrantz <jakob@vmware.com> Signed-off-by: Dave Airlie <airlied@redhat.com>