}
 #endif
 
+static int ext4_init_metadata_csum(struct super_block *sb, struct ext4_super_block *es)
+{
+       struct ext4_sb_info *sbi = EXT4_SB(sb);
+
+       /* Warn if metadata_csum and gdt_csum are both set. */
+       if (ext4_has_feature_metadata_csum(sb) &&
+           ext4_has_feature_gdt_csum(sb))
+               ext4_warning(sb, "metadata_csum and uninit_bg are "
+                            "redundant flags; please run fsck.");
+
+       /* Check for a known checksum algorithm */
+       if (!ext4_verify_csum_type(sb, es)) {
+               ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
+                        "unknown checksum algorithm.");
+               return -EINVAL;
+       }
+       ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
+                               ext4_orphan_file_block_trigger);
+
+       /* Load the checksum driver */
+       sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
+       if (IS_ERR(sbi->s_chksum_driver)) {
+               int ret = PTR_ERR(sbi->s_chksum_driver);
+               ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
+               sbi->s_chksum_driver = NULL;
+               return ret;
+       }
+
+       /* Check superblock checksum */
+       if (!ext4_superblock_csum_verify(sb, es)) {
+               ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
+                        "invalid superblock checksum.  Run e2fsck?");
+               return -EFSBADCRC;
+       }
+
+       /* Precompute checksum seed for all metadata */
+       if (ext4_has_feature_csum_seed(sb))
+               sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
+       else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
+               sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
+                                              sizeof(es->s_uuid));
+       return 0;
+}
+
 static int __ext4_fill_super(struct fs_context *fc, struct super_block *sb)
 {
        struct buffer_head *bh, **group_desc;
 
        sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
 
-       /* Warn if metadata_csum and gdt_csum are both set. */
-       if (ext4_has_feature_metadata_csum(sb) &&
-           ext4_has_feature_gdt_csum(sb))
-               ext4_warning(sb, "metadata_csum and uninit_bg are "
-                            "redundant flags; please run fsck.");
-
-       /* Check for a known checksum algorithm */
-       if (!ext4_verify_csum_type(sb, es)) {
-               ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
-                        "unknown checksum algorithm.");
-               goto failed_mount;
-       }
-       ext4_setup_csum_trigger(sb, EXT4_JTR_ORPHAN_FILE,
-                               ext4_orphan_file_block_trigger);
-
-       /* Load the checksum driver */
-       sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
-       if (IS_ERR(sbi->s_chksum_driver)) {
-               ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
-               ret = PTR_ERR(sbi->s_chksum_driver);
-               sbi->s_chksum_driver = NULL;
-               goto failed_mount;
-       }
-
-       /* Check superblock checksum */
-       if (!ext4_superblock_csum_verify(sb, es)) {
-               ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
-                        "invalid superblock checksum.  Run e2fsck?");
-               ret = -EFSBADCRC;
+       err = ext4_init_metadata_csum(sb, es);
+       if (err)
                goto failed_mount;
-       }
-
-       /* Precompute checksum seed for all metadata */
-       if (ext4_has_feature_csum_seed(sb))
-               sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
-       else if (ext4_has_metadata_csum(sb) || ext4_has_feature_ea_inode(sb))
-               sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
-                                              sizeof(es->s_uuid));
 
        ext4_set_def_opts(sb, es);