static void device_destroy(struct vm_store *store)
	Frees the space associated with this store

static off_t device_commit(struct vm_store *store, off_t size)
	Sets this store's commited size to size.

static int device_has_page(struct vm_store *store, off_t offset)
	Returns 0

static ssize_t device_read(struct vm_store *store, off_t offset, iovecs *vecs)
	Returns unimplemented.

static ssize_t device_write(struct vm_store *store, off_t offset, iovecs *vecs)
	Returns 0

static int device_fault(struct vm_store *store, struct vm_address_space *aspace, off_t offset)
	Should be called when a page is not mapped in. Locks the translation map, Finds the region in the cache that contains this page and maps it in. Unlocks the cache.

vm_store *vm_store_create_device(addr base_addr)   
	Allocates memory for the vm_store structure, plus the data_store_device structure. Sets cache to null, and data to the device_store_data. Sets the device_store_data's base address to the base address passed in.