block scsi eh until session state has transistioned
int iscsi_block_scsi_eh (
|struct scsi_cmnd * cmd|
scsi cmd passed to scsi eh handler
If the session is down this function will wait for the recovery
timer to fire or for the session to be logged back in. If the
recovery timer fires then FAST_IO_FAIL is returned. The caller
should pass this error value to the scsi eh.