From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mike Snitzer <snitzer@redhat.com>
Subject: Re: [PATCH v2] dm table: simplify discard support
	processing
Date: Mon, 18 Jul 2011 11:10:56 -0400
Message-ID: <20110718151055.GA7744@redhat.com>
References: <20110714143037.GA12049@redhat.com>
	<20110714175647.GA31051@redhat.com>
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Updated patch header to also point out the fix:

Remove 'discards_supported' from the dm_table structure.  The same
information can be easily discovered from the table's target(s) in
dm_table_supports_discards().

This change fixes an issue with per-target 'discards_supported' being
ineffective, at insuring the final DM device advertises discard support,
due to a different target not having 'num_discard_requests' > 0 -- this
resulted in the overall table's 'discards_supported' being set to 0.

Also DMWARN if a target sets 'discards_supported' override but forgets
to set 'num_discard_requests'.