diff options
| author | David Sterba <dsterba@suse.com> | 2018-03-02 22:56:53 +0100 |
|---|---|---|
| committer | David Sterba <dsterba@suse.com> | 2019-11-18 17:51:49 +0100 |
| commit | 47e6f7423b9196ad6832d26cae52b7015f81ee7f (patch) | |
| tree | 3f06408a77645e1546ed90445cf6584c515ca44d /fs/btrfs/volumes.c | |
| parent | fac07d2b091542f7169978e4c1413747d8d0e965 (diff) | |
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>
Diffstat (limited to 'fs/btrfs/volumes.c')
| -rw-r--r-- | fs/btrfs/volumes.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index e6c458d99722..d17835fbd52f 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -58,6 +58,18 @@ const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { .bg_flag = BTRFS_BLOCK_GROUP_RAID1, .mindev_error = BTRFS_ERROR_DEV_RAID1_MIN_NOT_MET, }, + [BTRFS_RAID_RAID1C3] = { + .sub_stripes = 1, + .dev_stripes = 1, + .devs_max = 0, + .devs_min = 3, + .tolerated_failures = 2, + .devs_increment = 3, + .ncopies = 3, + .raid_name = "raid1c3", + .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3, + .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET, + }, [BTRFS_RAID_DUP] = { .sub_stripes = 1, .dev_stripes = 2, @@ -4839,8 +4851,11 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans, sort(devices_info, ndevs, sizeof(struct btrfs_device_info), btrfs_cmp_device_info, NULL); - /* round down to number of usable stripes */ - ndevs = round_down(ndevs, devs_increment); + /* + * Round down to number of usable stripes, devs_increment can be any + * number so we can't use round_down() + */ + ndevs -= ndevs % devs_increment; if (ndevs < devs_min) { ret = -ENOSPC; |