u64 logical_start, u8 *csum, u8 *csum_expected, int mirror_num)
 {
        struct btrfs_root *root = inode->root;
-       struct btrfs_super_block *sb = root->fs_info->super_copy;
-       const u16 csum_size = btrfs_super_csum_size(sb);
+       const u16 csum_size = root->fs_info->csum_size;
 
        /* Output minus objectid, which is more meaningful */
        if (root->root_key.objectid >= BTRFS_LAST_FREE_OBJECTID)
 
                return -1;
        }
 
-       state->csum_size = btrfs_super_csum_size(selected_super);
+       state->csum_size = state->fs_info->csum_size;
 
        for (pass = 0; pass < 3; pass++) {
                int num_copies;
 
 static inline int compressed_bio_size(struct btrfs_fs_info *fs_info,
                                      unsigned long disk_size)
 {
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
 
        return sizeof(struct compressed_bio) +
                (DIV_ROUND_UP(disk_size, fs_info->sectorsize)) * csum_size;
 {
        struct btrfs_fs_info *fs_info = inode->root->fs_info;
        SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
-       const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        struct page *page;
        unsigned long i;
        char *kaddr;
        struct extent_map *em;
        blk_status_t ret = BLK_STS_RESOURCE;
        int faili = 0;
-       const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        u8 *sums;
 
        em_tree = &BTRFS_I(inode)->extent_tree;
 
        crypto_shash_digest(shash, raw_disk_sb + BTRFS_CSUM_SIZE,
                            BTRFS_SUPER_INFO_SIZE - BTRFS_CSUM_SIZE, result);
 
-       if (memcmp(disk_sb->csum, result, btrfs_super_csum_size(disk_sb)))
+       if (memcmp(disk_sb->csum, result, fs_info->csum_size))
                return 1;
 
        return 0;
        u64 start = page_offset(page);
        u64 found_start;
        u8 result[BTRFS_CSUM_SIZE];
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        struct extent_buffer *eb;
        int ret;
 
 
        eb = (struct extent_buffer *)page->private;
        fs_info = eb->fs_info;
-       csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       csum_size = fs_info->csum_size;
 
        /* the pending IO might have been the only thing that kept this buffer
         * in memory.  Make sure we have a ref for all this other checks
 
        repair_bio->bi_private = failed_bio->bi_private;
 
        if (failed_io_bio->csum) {
-               const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+               const u16 csum_size = fs_info->csum_size;
 
                repair_io_bio->csum = repair_io_bio->csum_inline;
                memcpy(repair_io_bio->csum,
 
        struct btrfs_csum_item *item;
        struct extent_buffer *leaf;
        u64 csum_offset = 0;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        int csums_in_item;
 
        file_key.objectid = BTRFS_EXTENT_CSUM_OBJECTID;
        u32 diff;
        int nblocks;
        int count = 0;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
 
        if (!fs_info->csum_root || (BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
                return BLK_STS_OK;
        int ret;
        size_t size;
        u64 csum_end;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
 
        ASSERT(IS_ALIGNED(start, fs_info->sectorsize) &&
               IS_ALIGNED(end + 1, fs_info->sectorsize));
        int i;
        u64 offset;
        unsigned nofs_flag;
-       const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
 
        nofs_flag = memalloc_nofs_save();
        sums = kvzalloc(btrfs_ordered_sum_size(fs_info, bio->bi_iter.bi_size),
                                       u64 bytenr, u64 len)
 {
        struct extent_buffer *leaf;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        u64 csum_end;
        u64 end_byte = bytenr + len;
        u32 blocksize_bits = fs_info->sectorsize_bits;
        u64 csum_end;
        struct extent_buffer *leaf;
        int ret;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        u32 blocksize_bits = fs_info->sectorsize_bits;
 
        ASSERT(root == fs_info->csum_root ||
        int index = 0;
        int found_next;
        int ret;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
 
        path = btrfs_alloc_path();
        if (!path)
 
        SHASH_DESC_ON_STACK(shash, fs_info->csum_shash);
        char *kaddr;
        u32 len = fs_info->sectorsize;
-       u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        u8 *csum_expected;
        u8 csum[BTRFS_CSUM_SIZE];
 
 
                csum_offset = file_offset - dip->logical_offset;
                csum_offset >>= fs_info->sectorsize_bits;
-               csum_offset *= btrfs_super_csum_size(fs_info->super_copy);
+               csum_offset *= fs_info->csum_size;
                btrfs_io_bio(bio)->csum = dip->csums + csum_offset;
        }
 map:
        dip_size = sizeof(*dip);
        if (!write && csum) {
                struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
-               const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+               const u16 csum_size = fs_info->csum_size;
                size_t nblocks;
 
                nblocks = dio_bio->bi_iter.bi_size >> fs_info->sectorsize_bits;
 
        struct btrfs_ordered_inode_tree *tree = &inode->ordered_tree;
        unsigned long num_sectors;
        unsigned long i;
-       const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
        int index = 0;
 
        ordered = btrfs_lookup_ordered_extent(inode, offset);
 
                                         unsigned long bytes)
 {
        int num_sectors = (int)DIV_ROUND_UP(bytes, fs_info->sectorsize);
-       int csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csum_size = fs_info->csum_size;
 
        return sizeof(struct btrfs_ordered_sum) + num_sectors * csum_size;
 }
 
        atomic_set(&sctx->bios_in_flight, 0);
        atomic_set(&sctx->workers_pending, 0);
        atomic_set(&sctx->cancel_req, 0);
-       sctx->csum_size = btrfs_super_csum_size(fs_info->super_copy);
+       sctx->csum_size = fs_info->csum_size;
 
        spin_lock_init(&sctx->list_lock);
        spin_lock_init(&sctx->stat_lock);
 
 {
        struct btrfs_fs_info *fs_info = leaf->fs_info;
        u32 sectorsize = fs_info->sectorsize;
-       u32 csumsize = btrfs_super_csum_size(fs_info->super_copy);
+       const u16 csumsize = fs_info->csum_size;
 
        if (key->objectid != BTRFS_EXTENT_CSUM_OBJECTID) {
                generic_err(leaf, slot,