Alexander Motin 0ac03010f6 Make delete method set via kern.cam.da.X.delete_method persistent.
This allows to set delete method via tunable, before device capabilities
are known.  Also allow ZERO method for devices not reporting LBP, if user
explicitly requests it -- it may be useful if storage supports compression
and WRITE SAME, but does not support UNMAP.

MFC after:	2 weeks
2015-10-11 18:26:06 +00:00
..
2015-09-18 10:44:25 +00:00
2012-05-24 14:07:44 +00:00