On Mon, 2017-03-27 at 10:03 -0400, Mike Snitzer wrote: > As for the blkdev_issue_zeroout() resorting to manually zeroing the > range, if the discard fails or dzd not supported, that certainly > requires DM thinp to implement manual zeroing of the head and tail of > the range if partial blocks are being zeroed. So I welcome any advances > there. It is probably something that is best left to Joe or myself to > tackle. But I'll gladly accept patches ;) Some time ago I posted a patch series for the block layer that zeroes start and tail for nonaligned discard requests if dzd has been set. See also "[PATCH v3 0/5] Make blkdev_issue_discard() submit aligned discard requests" (https://www.spinics.net/lists/linux-block/msg02360.html). Bart.
