Abstract: Provided are a method, system, and program for transferring data among a logical layer, physical layer, and storage device. The logical layer allocates a buffer to use to write data to a storage device. The physical layer manages access to the storage device. The logical layer determines an offset into the buffer based on a length of a physical header written by the physical layer and writes data to the buffer from the determined offset. The physical layer writes physical header information, wherein the physical header information does not extend past the offset in the buffer. The physical layer transfers content from the buffer to the storage device.