xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

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

Browse Source 
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>
This commit is contained in:
David Sterba
2018-03-02 22:56:53 +01:00
parent fac07d2b09
commit 47e6f7423b
6 changed files with 30 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
fs/btrfs/ctree.h
View File

@@ -57,9 +57,9 @@ struct btrfs_ref;
* filesystem data as well that can be used to read data in order to repair
* read errors on other disks.
*
* Current value is derived from RAID1 with 2 copies.
* Current value is derived from RAID1C3 with 3 copies.
*/
#define BTRFS_MAX_MIRRORS (2 + 1)
#define BTRFS_MAX_MIRRORS (3 + 1)
#define BTRFS_MAX_LEVEL 8