Hybrid-hdd policy for what host-r/w data goes into nand

A method of operating a storage device having a magnetic storage device and a non-volatile solid-state device, the method comprising:

• receiving a write command that includes a logical block address and write data associated with the logical block address;
• determining that previously written data are stored in the non-volatile solid-state device that are associated with the logical block address;
• and
• in response to determining that the previously written data stored in the non-volatile solid-state device are associated with the logical block address, storing the write data in the non-volatile solid-state device.

A data storage device comprising:

• a magnetic storage device;
• a non-volatile solid-state device;
• and
• a controller configured to receive data to be written in units of host sectors, the data including a head portion, a middle portion, and tail portion, and to write the head portion of the data into the non-volatile solid-state device, the middle portion of the data into the magnetic storage device, and the tail portion of the data into the non-volatile solid-state device.