1 files changed, 15 insertions, 2 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 1eda6ab0ef9d..2c9e6864abd9 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3526,6 +3526,10 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
         set_opt(sb, POSIX_ACL);
 #endif
+        /* don't forget to enable journal_csum when metadata_csum is enabled. */
+        if (ext4_has_metadata_csum(sb))
+                set_opt(sb, JOURNAL_CHECKSUM);
+
         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
                 set_opt(sb, JOURNAL_DATA);
         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
@@ -3943,7 +3947,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         if (EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_MMP) &&
             !(sb->s_flags & MS_RDONLY))
                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
-                        goto failed_mount3;
+                        goto failed_mount3a;
 
         /*
          * The first inode we look at is the journal inode.  Don't try
@@ -3952,7 +3956,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         if (!test_opt(sb, NOLOAD) &&
             EXT4_HAS_COMPAT_FEATURE(sb, EXT4_FEATURE_COMPAT_HAS_JOURNAL)) {
                 if (ext4_load_journal(sb, es, journal_devnum))
-                        goto failed_mount3;
+                        goto failed_mount3a;
         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
               EXT4_HAS_INCOMPAT_FEATURE(sb, EXT4_FEATURE_INCOMPAT_RECOVER)) {
                 ext4_msg(sb, KERN_ERR, "required journal recovery "
@@ -4240,6 +4244,7 @@ failed_mount_wq:
                 jbd2_journal_destroy(sbi->s_journal);
                 sbi->s_journal = NULL;
         }
+failed_mount3a:
         ext4_es_unregister_shrinker(sbi);
 failed_mount3:
         del_timer_sync(&sbi->s_err_report);
@@ -4841,6 +4846,14 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data)
                 goto restore_opts;
         }
 
+        if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
+            test_opt(sb, JOURNAL_CHECKSUM)) {
+                ext4_msg(sb, KERN_ERR, "changing journal_checksum "
+                         "during remount not supported");
+                err = -EINVAL;
+                goto restore_opts;
+        }
+
         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
                         ext4_msg(sb, KERN_ERR, "can't mount with "