TAKE - xfs_dm_send_data_event() breaks some HSMs

[Dean Roehrich <roehrich@xxxxxxx>]

Date:  Thu Aug 22 13:04:46 PDT 2002
Workarea:  clink-eth.americas.sgi.com:/data/clink/a67/roehrich/2.4.x-xfs

The following file(s) were checked into:
  bonnie.engr.sgi.com:/isms/slinx/2.4.x-xfs


Modid:  2.4.x-xfs:slinx:125722a
linux/fs/xfs/xfs_dmapi.c - 1.76
        - We'll use dmstate to keep a counter and use this to coordinate
          activity between xfs_dm_punch_hole and xfs_dm_send_data_event.
          Checking DM_EVENT_ENABLED got us into trouble.  By checking that 
event,
          after you've already sent it, you're dictating behavior to the 
HSM--that it
          must clear the event's bit from the event mask before responding to 
the event.
          The DMAPI spec does not require that HSMs behave this way, and some, 
like
          Veritas's, don't.