Hi all, In this sixth part of the twenty-second revision of the online repair patchset, we provide all the repair features that require the entire filesystem to be frozen. Patch 1 gives scrub the ability to freeze the filesystem so that it can do scans and repairs in mostly-exclusive mode. Patch 2 is unnecessary? It provides async io for xfile, which has massive overhead costs but mostly shuts up lockdep. Patch 3 implements reverse mapping btree reconstruction. Patch 4 reimplements quotacheck as an online operation. Patch 5 implements a summary counter repair function. In contrast to its scrub-only counterpart, if we decide to repair the summary counters we need to freeze the filesystem to prevent any concurrent operations while we calculate the correct value for the summary counters. If you're going to start using this mess, you probably ought to just pull from my git trees, which are linked below. This is an extraordinary way to destroy everything. Enjoy! Comments and questions are, as always, welcome. --D kernel git tree: https://git.kernel.org/cgit/linux/kernel/git/djwong/xfs-linux.git/log/?h=repair-hard-problems xfsprogs git tree: https://git.kernel.org/cgit/linux/kernel/git/djwong/xfsprogs-dev.git/log/?h=repair-hard-problems