tree 3f06408a77645e1546ed90445cf6584c515ca44d
parent fac07d2b091542f7169978e4c1413747d8d0e965
author David Sterba <dsterba@suse.com> 1520027813 +0100
committer David Sterba <dsterba@suse.com> 1574095909 +0100

btrfs: add support for 3-copy replication (raid1c3)

Add new block group profile to store 3 copies in a simliar way that
current RAID1 does. The profile attributes and constraints are defined
in the raid table and used by the same code that already handles the
2-copy RAID1.

The minimum number of devices is 3, the maximum number of devices/chunks
that can be lost/damaged is 2. Like RAID6 but with 33% space
utilization.

Signed-off-by: David Sterba <dsterba@suse.com>