Storage device and storage control method

A storage device, comprising:

• a nonvolatile semiconductor memory having a first region and a second region, and storing an address conversion table that is used to convert logical addresses into physical addresses of the nonvolatile semiconductor memory;
• and
• a controller configured to store user data in a buffer memory in response to a write command associated with a logical address and user data, received from a host, and notify the host of completion of the write command, wherein
• subsequent to notifying the host of completion of the write command, the controller writes the user data stored in the buffer memory into the nonvolatile semiconductor memory at a physical address, and generates an address update request for updating a correspondence relationship between the logical address and the physical address for the user data, and
• the controller generates table read requests for reading portions of the address conversion table from the nonvolatile semiconductor memory in response to one or more address update requests, classifies the table read requests as first requests for reading data from the first region and second read requests for reading data from the second region, pairs one of the first read requests with one of the second read requests to generate a third read request, and outputs the third read request to the nonvolatile semiconductor memory.

A storage control method, comprising:

• generating a plurality of read requests for reading data from a nonvolatile semiconductor memory that includes a first region and a second region;
• classifying the plurality of read requests into first read requests for reading data from the first region and second read requests for reading data from the second region;
• pairing one of the first read requests with one of the second read requests to generate a third read request;
• and
• outputting the third read request to the nonvolatile semiconductor memory, in response to which the nonvolatile semiconductor memory performs a read operation in the first region in parallel with a read operation in the second region.