Your question stumped me. I dont know of any view within oracle to show the sql loader process status. SQL Loader command line parameter log=xxx.log will create a log file and you can view that log to see the progress.
You can probably query the v$SQL view to see the SQL Stmts that SQL Loader is executing and the number of times it has executed them. (unless you are using the DIRECT=Y parameter, which does not insert data with SQL stmts)
Also, this query will show you disk I/O by session. It could
easily be modified to show only the session that you are interested in once you know the SID from v$SESSION.
select s.username "Oracle User", s.sid "Session",
i.block_gets "Block Gets", i.consistent_gets "Consistent Gets",
i.physical_reads "Physical Reads", i.block_changes "Block Changes",
i.consistent_changes "Consistent Changes",
s.machine "Computer", s.program "Program", s.logon_time "Logon Time"
from sys.v_$sess_io i, sys.v_$session s
where i.sid = s.sid
and s.username is not null
ORDER BY 3 desc