ext4: create nojournal_checksum mount option
Create a mount option to disable journal checksumming (because the
metadata_csum feature turns it on by default now), and fix remount not
to allow changing the journal checksumming option, since changing the
mount options has no effect on the journal.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index b643009..3bd2982 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1136,7 +1136,7 @@
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 @@
{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 @@
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 @@
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 "