1 files changed, 12 insertions, 1 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index b643009fddfe..3bd2982da36d 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1136,7 +1136,7 @@ enum {
         Opt_inode_readahead_blks, Opt_journal_ioprio,
         Opt_dioread_nolock, Opt_dioread_lock,
         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
-        Opt_max_dir_size_kb,
+        Opt_max_dir_size_kb, Opt_nojournal_checksum,
 };
 
 static const match_table_t tokens = {
@@ -1170,6 +1170,7 @@ static const match_table_t tokens = {
         {Opt_journal_dev, "journal_dev=%u"},
         {Opt_journal_path, "journal_path=%s"},
         {Opt_journal_checksum, "journal_checksum"},
+        {Opt_nojournal_checksum, "nojournal_checksum"},
         {Opt_journal_async_commit, "journal_async_commit"},
         {Opt_abort, "abort"},
         {Opt_data_journal, "data=journal"},
@@ -1351,6 +1352,8 @@ static const struct mount_opts {
          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
          MOPT_EXT4_ONLY | MOPT_CLEAR},
+        {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
+         MOPT_EXT4_ONLY | MOPT_CLEAR},
         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
          MOPT_EXT4_ONLY | MOPT_SET},
         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
@@ -4844,6 +4847,14 @@ 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 "