diff options
Diffstat (limited to 'fs/btrfs/volumes.h')
| -rw-r--r-- | fs/btrfs/volumes.h | 39 |
1 files changed, 30 insertions, 9 deletions
diff --git a/fs/btrfs/volumes.h b/fs/btrfs/volumes.h index 7b82aae89454..12b2af9260e9 100644 --- a/fs/btrfs/volumes.h +++ b/fs/btrfs/volumes.h @@ -17,16 +17,37 @@ extern struct mutex uuid_mutex; #define BTRFS_STRIPE_LEN SZ_64K +/* Used by sanity check for btrfs_raid_types. */ +#define const_ffs(n) (__builtin_ctzll(n) + 1) + +/* + * The conversion from BTRFS_BLOCK_GROUP_* bits to btrfs_raid_type requires + * RAID0 always to be the lowest profile bit. + * Although it's part of on-disk format and should never change, do extra + * compile-time sanity checks. + */ +static_assert(const_ffs(BTRFS_BLOCK_GROUP_RAID0) < + const_ffs(BTRFS_BLOCK_GROUP_PROFILE_MASK & ~BTRFS_BLOCK_GROUP_RAID0)); +static_assert(const_ilog2(BTRFS_BLOCK_GROUP_RAID0) > + ilog2(BTRFS_BLOCK_GROUP_TYPE_MASK)); + +/* ilog2() can handle both constants and variables */ +#define BTRFS_BG_FLAG_TO_INDEX(profile) \ + ilog2((profile) >> (ilog2(BTRFS_BLOCK_GROUP_RAID0) - 1)) + enum btrfs_raid_types { - BTRFS_RAID_RAID10, - BTRFS_RAID_RAID1, - BTRFS_RAID_DUP, - BTRFS_RAID_RAID0, - BTRFS_RAID_SINGLE, - BTRFS_RAID_RAID5, - BTRFS_RAID_RAID6, - BTRFS_RAID_RAID1C3, - BTRFS_RAID_RAID1C4, + /* SINGLE is the special one as it doesn't have on-disk bit. */ + BTRFS_RAID_SINGLE = 0, + + BTRFS_RAID_RAID0 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID0), + BTRFS_RAID_RAID1 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1), + BTRFS_RAID_DUP = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_DUP), + BTRFS_RAID_RAID10 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID10), + BTRFS_RAID_RAID5 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID5), + BTRFS_RAID_RAID6 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID6), + BTRFS_RAID_RAID1C3 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C3), + BTRFS_RAID_RAID1C4 = BTRFS_BG_FLAG_TO_INDEX(BTRFS_BLOCK_GROUP_RAID1C4), + BTRFS_NR_RAID_TYPES }; |