From 8d6fac0087e538173f34ca7431ed9b58581acf28 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Fri, 2 Mar 2018 22:56:53 +0100 Subject: btrfs: add support for 4-copy replication (raid1c4) Add new block group profile to store 4 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- and 3-copy RAID1. The minimum number of devices is 4, the maximum number of devices/chunks that can be lost/damaged is 3. There is no comparable traditional RAID level, the profile is added for future needs to accompany triple-parity and beyond. Signed-off-by: David Sterba --- fs/btrfs/volumes.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'fs/btrfs/volumes.h') diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index a4e26b84e1b9..46987a2da786 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -547,6 +547,8 @@ static inline enum btrfs_raid_types btrfs_bg_flags_to_raid_index(u64 flags) return BTRFS_RAID_RAID1; else if (flags & BTRFS_BLOCK_GROUP_RAID1C3) return BTRFS_RAID_RAID1C3; + else if (flags & BTRFS_BLOCK_GROUP_RAID1C4) + return BTRFS_RAID_RAID1C4; else if (flags & BTRFS_BLOCK_GROUP_DUP) return BTRFS_RAID_DUP; else if (flags & BTRFS_BLOCK_GROUP_RAID0) -- cgit v1.2.3-59-g8ed1b