Initial Android implementation for A/B boot
Provide a GBL interface for the Android reference implementation of
A/B slotted boot semantics.
Note: The reference implementation permits but does not require up to
four slots. This makes it difficult to reconstruct a default
metadata structure without scanning the partition table to
determine the actual number of slots.
The current implementation defaults to assuming 4 slots.
Note: This change does NOT fully support Android A/B semantics.
In particular this change does not handle booting to recovery.
Those changes will be made subsequently and will require some
additional modifications for scatter/gather disk access.
Tests: unit tests all pass
Change-Id: I1c6f2e39c5afbd618d08e243b21727705ef6e9c7
4 files changed
