Hello all, We do btrfs subvolume snapshots over time for backups. I would like to traverse the files in the subvolumes and find the total unique chunk count to calculate total space for a set of subvolumes. This sounds kind of like the beginning of what a deduplicator would do, but I just want to count the blocks, so no submission for deduplication. I started looking at bedup and other deduplicator code, but the answer to this question wasn't obvious (to me, anyway). Questions: Is there an ioctl (or some other way) to get the block device offset for a file (or file offset) so I can count the unique occurances? What API documentation should I review? Can you point me at the ioctl(s) that would handle this? Thank you for your help! -- Eric Wheeler -- 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
