On Fri, Apr 20, 2018 at 04:21:43PM +0200, David Sterba wrote: > This patchset adds new ioctl similar to TRIM, that provides several > other ways how to clear the unused space. The changelogs are > incomplete, for preview not for inclusion yet. > > It compiles and has been tested lightly, the clearing modes depend on hw > capabilities (secure discard, sector unmapping instead of zeros), so > I've tested only zeroing and discard. > > I personally think the zeroing has a usecase and the other modes were > easy to add. Further extensions can be considered, eg. WRITE_SAME, > overwriting with a randomly generated pattern, or some filesystem canary > patterns that can be used to report unused block read as metadata. > > As this is modelled after the generic FITRIM ioctl, so this could be a > new generic ioctl too. However, last time somebody wanted such ioctl, > there was a pushback. I'll consider making a generic version and send it > for comments to fsdevel eventually. > > git://github.com/kdave/btrfs-devel dev/zero-free > > > David Sterba (6): > btrfs: extend trim callchain to pass the operation type > btrfs: add wrapper to switch clearing operation > btrfs: add zeroing clear operation > btrfs: add new ioctl BTRFS_IOC_CLEAR_FREE > btrfs: add discard secure to clear unused space > btrfs: add more zeroout modes for clearing unused space For the record, this patchset has been shifted to 4.19 or later. -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
