Thanks for the feedback, Mike. On Wed, 3 Jan 2018 12:33:32 -0600, Mike Christie wrote: > > Block layer backed logical units are capable of deferring to the block > > layer when determining UNMAP attributes, but this logic currently leaves > > the emulate_tpu (UNMAP) and emulate_tpws (WRITE_SAME with UNMAP=1) flags > > disabled. > > Is there any cases where the user set tpu/tpws to off on purpose to > work around a backing device or initiator side issue? If so, I think the > only concern would be for non-rtslib based apps. If they did the attrib > setting stage after device creation but before the config stage, then > this patch would overwrite those settings. I'm not aware of any such cases, but yes, good point. If this is a concern, then another option would be to change the DA_EMULATE_TPU/TPWS defaults unconditionally (for all backstores), but I that'd lead to other consequences (e.g. on FSes that don't support PUNCH_HOLE). > For rtslib based apps, if the user had set tpu/tpws values to off on > purpose, it looks like the user requested values will still be used > since the attrib setting stage is done after the configure. > > If we do not support non rtslib based apps then the patch is nice for > users and looks ok. FWIW, I frequently use LIO via configfs directly (without rtslib), so would like to ensure continued compatibility. > Reviewed-by: Mike Christie <mchristi@xxxxxxxxxx> Cheers, David -- To unsubscribe from this list: send the line "unsubscribe target-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
