On Thu, Jan 28, 2016 at 01:50:19PM +0000, Andy Whitcroft wrote: > However this also removed the possibility of a dm target having target > specific ioctls. Currently this is not used by any in-tree targets but > was utilised by the flashcache out-of-tree module. What data is being passed in and out? The method we support is passing it through DM_TARGET_MSG (as text). For examples look at dm-switch.c and dm-stats.c, which handled pretty large quantities of data. Would that work? Alasdair -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel