From 8d6fac0087e538173f34ca7431ed9b58581acf28 Mon Sep 17 00:00:00 2001 From: David Sterba Date: Fri, 2 Mar 2018 22:56:53 +0100 Subject: [PATCH] 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/ctree.h | 4 ++-- fs/btrfs/super.c | 2 ++ fs/btrfs/volumes.c | 12 ++++++++++++ fs/btrfs/volumes.h | 2 ++ include/uapi/linux/btrfs.h | 1 + include/uapi/linux/btrfs_tree.h | 6 +++++- 6 files changed, 24 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index aa1b437fb951..923a8804ae94 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -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 RAID1C3 with 3 copies. + * Current value is derived from RAID1C4 with 4 copies. */ -#define BTRFS_MAX_MIRRORS (3 + 1) +#define BTRFS_MAX_MIRRORS (4 + 1) #define BTRFS_MAX_LEVEL 8 diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index a5aff138e2e0..a98c3c71fc54 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1937,6 +1937,8 @@ static inline int btrfs_calc_avail_data_space(struct btrfs_fs_info *fs_info, num_stripes = 2; else if (type & BTRFS_BLOCK_GROUP_RAID1C3) num_stripes = 3; + else if (type & BTRFS_BLOCK_GROUP_RAID1C4) + num_stripes = 4; else if (type & BTRFS_BLOCK_GROUP_RAID10) num_stripes = 4; diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index d17835fbd52f..9054203ae671 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -70,6 +70,18 @@ const struct btrfs_raid_attr btrfs_raid_array[BTRFS_NR_RAID_TYPES] = { .bg_flag = BTRFS_BLOCK_GROUP_RAID1C3, .mindev_error = BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET, }, + [BTRFS_RAID_RAID1C4] = { + .sub_stripes = 1, + .dev_stripes = 1, + .devs_max = 0, + .devs_min = 4, + .tolerated_failures = 3, + .devs_increment = 4, + .ncopies = 4, + .raid_name = "raid1c4", + .bg_flag = BTRFS_BLOCK_GROUP_RAID1C4, + .mindev_error = BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET, + }, [BTRFS_RAID_DUP] = { .sub_stripes = 1, .dev_stripes = 2, 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) diff --git a/include/uapi/linux/btrfs.h b/include/uapi/linux/btrfs.h index ba22f91a3f5b..a2b761275bba 100644 --- a/include/uapi/linux/btrfs.h +++ b/include/uapi/linux/btrfs.h @@ -833,6 +833,7 @@ enum btrfs_err_code { BTRFS_ERROR_DEV_ONLY_WRITABLE, BTRFS_ERROR_DEV_EXCL_RUN_IN_PROGRESS, BTRFS_ERROR_DEV_RAID1C3_MIN_NOT_MET, + BTRFS_ERROR_DEV_RAID1C4_MIN_NOT_MET, }; #define BTRFS_IOC_SNAP_CREATE _IOW(BTRFS_IOCTL_MAGIC, 1, \ diff --git a/include/uapi/linux/btrfs_tree.h b/include/uapi/linux/btrfs_tree.h index 52b2964b0311..8e322e2c7e78 100644 --- a/include/uapi/linux/btrfs_tree.h +++ b/include/uapi/linux/btrfs_tree.h @@ -842,6 +842,7 @@ struct btrfs_dev_replace_item { #define BTRFS_BLOCK_GROUP_RAID5 (1ULL << 7) #define BTRFS_BLOCK_GROUP_RAID6 (1ULL << 8) #define BTRFS_BLOCK_GROUP_RAID1C3 (1ULL << 9) +#define BTRFS_BLOCK_GROUP_RAID1C4 (1ULL << 10) #define BTRFS_BLOCK_GROUP_RESERVED (BTRFS_AVAIL_ALLOC_BIT_SINGLE | \ BTRFS_SPACE_INFO_GLOBAL_RSV) @@ -854,6 +855,7 @@ enum btrfs_raid_types { BTRFS_RAID_RAID5, BTRFS_RAID_RAID6, BTRFS_RAID_RAID1C3, + BTRFS_RAID_RAID1C4, BTRFS_NR_RAID_TYPES }; @@ -864,6 +866,7 @@ enum btrfs_raid_types { #define BTRFS_BLOCK_GROUP_PROFILE_MASK (BTRFS_BLOCK_GROUP_RAID0 | \ BTRFS_BLOCK_GROUP_RAID1 | \ BTRFS_BLOCK_GROUP_RAID1C3 | \ + BTRFS_BLOCK_GROUP_RAID1C4 | \ BTRFS_BLOCK_GROUP_RAID5 | \ BTRFS_BLOCK_GROUP_RAID6 | \ BTRFS_BLOCK_GROUP_DUP | \ @@ -872,7 +875,8 @@ enum btrfs_raid_types { BTRFS_BLOCK_GROUP_RAID6) #define BTRFS_BLOCK_GROUP_RAID1_MASK (BTRFS_BLOCK_GROUP_RAID1 | \ - BTRFS_BLOCK_GROUP_RAID1C3) + BTRFS_BLOCK_GROUP_RAID1C3 | \ + BTRFS_BLOCK_GROUP_RAID1C4) /* * We need a bit for restriper to be able to tell when chunks of type -- GitLab