* grub-core/disk/scsi.c (grub_scsi_read16): New function. (grub_scsi_write16): Likewise. (grub_scsi_read): Use read16 when necessary. (grub_scsi_write): Likewise. * include/grub/scsicmd.h (grub_scsi_read16): New struct. (grub_scsi_write16): Likewise. (grub_scsi_cmd_t): Add READ16 and WRITE16.