K 10
svn:author
V 3
smh
K 8
svn:date
V 27
2013-03-21T09:34:41.641097Z
K 7
svn:log
V 480
Add TRIM support for L2ARC.

This adds TRIM support to cache vdevs. When ARC buffers are removed
from the L2ARC in arc_hdr_destroy(), arc_release() or l2arc_evict(),
the size previously occupied by the buffer gets scheduled for TRIMming.
As always, actual TRIMs are only issued to the L2ARC after
txg_trim_limit.

Reviewed by:	pjd (mentor)
Approved by:	pjd (mentor)
Obtained from:	https://github.com/dechamps/zfs/commit/31aae373994fd112256607edba7de2359da3e9dc
MFC after:	2 weeks

END