Virtual File System for Dynamic Immutable Image Composition

The patent divides the file system into multiple independent read-only images (e.g., base system image, application images, configuration images). Each image can be updated independently without affecting others, allowing configuration settings to be preserved while applying software updates. This segmentation resolves the contradiction by enabling selective updates that maintain reliability without requiring complex replacement processes.

The patent introduces a virtual file system as an intermediary layer that dynamically composes multiple read-only images. This virtual layer acts as a mediator between the immutable images and the running system, allowing flexible composition and modification without altering the original images. The intermediary enables updates to be applied while preserving configurations, avoiding the complexity of direct file system replacement.

The patent makes the static immutable images dynamic through a virtual file system that can compose and reconfigure them at runtime. While the individual images remain immutable (maintaining ease of operation), the system becomes adaptable by dynamically selecting and composing different images based on user needs or system state. This resolves the contradiction by adding dynamic composition capability without compromising the simplicity of using immutable images.

The patent creates a universal virtual file system that can handle multiple types of images (base system, applications, configurations) through a single interface. This multi-functional system can compose different combinations of images for different purposes while maintaining the simplicity of immutable image operation. The universal approach enables adaptability without requiring complex device operation changes.

The patent segments the file system tree into separate read-only images, each containing specific software components. This segmentation isolates conflicts between components and allows the virtual file system to compose them in a controlled manner. By dividing the monolithic file system into manageable images, the patent maintains functional versatility while reducing overall system complexity.

The patent uses copies of file system images that remain immutable while creating a virtual composition layer. Instead of modifying the original file system tree to accommodate multiple components, the system creates virtual copies that reference the same immutable images. This approach maintains versatility through multiple component combinations while avoiding the complexity of managing a monolithic file system with all components installed simultaneously.