btrfs filesystem show displays allocated space, but how can userspace know how much space is used on each device? In #btrfs channel on freenode.net, it was answered that the TREE_SEARCH ioctl can be used to inspect the data structures, and that btrfs-gui does this (thanks @darkling): http://carfax.org.uk/btrfs-gui However, it would be good if third-party applications had means to get this information from btrfs, without reimplementing what btrfs-gui does. For example, partitioning tools would be able to show an accurate number, rather than 0 or an estimate. Please, implement something in btrfs that returns this information. Thanks -- 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
