Method and system for handling host commands overlapping with deferred unmap address ranges in storage devices

Abstract

A storage device processes deferred unmap operations while maintaining instructions in a write command. A controller in a storage device receives an unmap command and a write command from a host, determines that a logical page in the write command overlaps with a range in the unmap command with deferred unmap operations, and processes the write command. In processing the write command, an L2P translation manager sets a collision bit for the logical page and updates a L2P table. When processing the deferred unmap operations, the controller selects the range and if, based on collision bits in the range the controller determines that there is no overlap between the write command and the range, the controller performs the deferred unmap operations for the range. If the controller determines that there is an overlap, the controller processes the deferred unmap operations to not override the write command.