On Tue, Feb 18, 2025 at 10:13:36PM -0800, Darrick J. Wong wrote: > Alternately we could make the log replay program call > fallocate(PUNCH_HOLE) on the block device before trying > fallocate(ZERO_RANGE) because AFAICT punch-hole has always called > blkdev_issue_zeroout with NOFALLBACK. The downside is that fallocate > for block devices came long after BLKDISCARD/BLKZEROOUT so we can't > remove the BLK* ioctl calls without losing some coverage. FALLOC_FL_ZERO_RANGE on block devices has been around since 2016, so I don't think that's a problem. The problem is more that it isn't supported on dm-thin at all.
