#!/bin/sh
sdx=sdb
#load the device with these params
modprobe scsi_debug virtual_gb=32 delay=0 dev_size_mb=32 fake_rw=1

# go set some live params
# $ cd /sys/bus/pseudo/drivers/scsi_debug
# $ echo 1 > fake_rw

# mess with sglist chaining
cd /sys/block/$sdx/queue
echo 4096 > max_segments
cat max_hw_sectors_kb  > max_sectors_kb
echo "max_hw_sectors_kb="$(cat max_hw_sectors_kb) 
echo "max_hw_sectors_kb="$(cat max_sectors_kb) 
echo "max_hw_sectors_kb="$(cat max_segments)