According to one embodiment, a controller writes first write data transferred from a first buffer and code data for second write data different from the first write data, the code data being transferred from a second buffer, in parallel to a plurality of physical pages corresponding to a first logical page. The controller writes code data for the first write data to a physical page corresponding to a second logical page, the second logical page being next to the first logical page, at a time of write to the nonvolatile memory following the write of the first write data and the code data for the second write data.