discard on snapshot-origin target

discard on snapshot-origin target

[Marek Marczykowski-Górecki]

[-- Attachment #1.1: Type: text/plain, Size: 790 bytes --]

Hi,

Is it possible to enable DISCARD support for snapshot-origin target?
Currently it returns EOPNOTSUPP even if underlying device does support
it. I know there are some cases when it isn't desirable (for example
mkfs.ext4 discards the entire device, which would trigger copyout to the
snapshot), but I can live with that. 

Or, if possible, better to prevent that copyout if discarded block(s)
were zeroed already. Which would handle the case of mkfs.ext4 on empty,
zeroed device.

I see that it may undesired in some cases, so maybe some configurable
option? Like module parameter or so?

-- 
Best Regards,
Marek Marczykowski-Górecki
Invisible Things Lab
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?

[-- Attachment #1.2: signature.asc --]
[-- Type: application/pgp-signature, Size: 473 bytes --]

[-- Attachment #2: Type: text/plain, Size: 0 bytes --]