tcm_qla2xxx jam_host attribute
  ------------------------------
  There is now a new module endpoint atribute called jam_host
  attribute: jam_host: boolean=0/1
  This attribute and accompanying code is only included if the
  Kconfig parameter TCM_QLA2XXX_DEBUG is set to Y
  By default this jammer code and functionality is disabled
  
  Use this attribute to control the discarding of SCSI commands to a
  selected host.
  This may be useful for testing error handling and simulating slow drain
  and other fabric issues.
  
  Setting a boolean of 1 for the jam_host attribute for a particular host
   will discard the commands for that host.
  Reset back to 0 to stop the jamming.
  
  Enable host 4 to be jammed
  echo 1 > /sys/kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host
  
  Disable jamming on host 4
  echo 0 > /sys/kernel/config/target/qla2xxx/21:00:00:24:ff:27:8f:ae/tpgt_1/attrib/jam_host