Existe um documento sobre o kernel do Linux sobre "midlayer_implementation"
SCSI midlayer implementation
include/scsi/scsi_device.h drivers/scsi/scsi.c drivers/scsi/scsicam.c drivers/scsi/scsi_error.c drivers/scsi/scsi_devinfo.c drivers/scsi/scsi_ioctl.c drivers/scsi/scsi_lib.c drivers/scsi/scsi_lib_dma.c drivers/scsi/scsi_module.c drivers/scsi/scsi_proc.c drivers/scsi/scsi_netlink.c drivers/scsi/scsi_scan.c drivers/scsi/scsi_sysctl.c drivers/scsi/scsi_sysfs.c drivers/scsi/hosts.c drivers/scsi/constants.c