This is preparatory work for RAID1C3, making use of the raid_attr table that replaces the hand crafted if-else-if sequences and bit mask checks. Pluging a new bg profile is easy on top of that, though there are still some possible cleanups left.
There's one user-visible change, patch 2/15, where the balance filters allow conversion to the RAID56 profiles with the minimum number of devices. This is for consistency with mkfs/mount. So this will work: $ mkfs.btrfs -d raid1 -m raid1 /dev/sda /dev/sdb $ mount dev/sda /mnt $ btrfs balance start -dconvert=raid5 -mconvert=raid5 /mnt David Sterba (15): btrfs: fix minimum number of chunk errors for DUP btrfs: raid56: allow the exact minimum number of devices for balance convert btrfs: remove mapping tree structures indirection btrfs: use raid_attr table in get_profile_num_devs btrfs: use raid_attr in btrfs_chunk_max_errors btrfs: use raid_attr table in calc_stripe_length for nparity btrfs: use raid_attr to get allowed profiles for balance conversion btrfs: use raid_attr table to find profiles for integrity lowering btrfs: use raid_attr table for btrfs_bg_type_to_factor btrfs: factor out helper for counting data stripes btrfs: use u8 for raid_array members btrfs: factor out devs_max setting in __btrfs_alloc_chunk btrfs: refactor helper for bg flags to name conversion btrfs: constify map parameter for nr_parity_stripes and nr_data_stripes btrfs: read number of data stripes from map only once fs/btrfs/ctree.h | 6 +- fs/btrfs/dev-replace.c | 2 +- fs/btrfs/disk-io.c | 6 +- fs/btrfs/extent-tree.c | 28 ++--- fs/btrfs/free-space-cache.c | 2 +- fs/btrfs/raid56.h | 4 +- fs/btrfs/scrub.c | 16 +-- fs/btrfs/volumes.c | 202 ++++++++++++++++-------------------- fs/btrfs/volumes.h | 24 ++--- 9 files changed, 125 insertions(+), 165 deletions(-) -- 2.21.0