Check for incompatible mount options when using the ext4 file system
driver to mount ext2 or ext3 file systems.
Signed-off-by: "Theodore Ts'o" <tytso@xxxxxxx>
---
fs/ext4/super.c | 47 +++++++++++++++++++++++++++++++++++------------
1 file changed, 35 insertions(+), 12 deletions(-)
diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index bcd5f12..b132df5 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1409,6 +1409,9 @@ static int clear_qf_name(struct super_block *sb, int qtype)
#define MOPT_QFMT MOPT_NOSUPPORT
#endif
#define MOPT_DATAJ 0x0080
+#define MOPT_NO_EXT2 0x0100
+#define MOPT_NO_EXT3 0x0200
+#define MOPT_EXT4_ONLY (MOPT_NO_EXT2 | MOPT_NO_EXT3)
static const struct mount_opts {
int token;
@@ -1421,21 +1424,29 @@ static const struct mount_opts {
{Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
{Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
{Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
- {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_SET},
- {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK, MOPT_CLEAR},
+ {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
+ MOPT_EXT4_ONLY | MOPT_SET},
+ {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
+ MOPT_EXT4_ONLY | MOPT_CLEAR},
{Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
{Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
- {Opt_delalloc, EXT4_MOUNT_DELALLOC, MOPT_SET | MOPT_EXPLICIT},
- {Opt_nodelalloc, EXT4_MOUNT_DELALLOC, MOPT_CLEAR | MOPT_EXPLICIT},
- {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM, MOPT_SET},
+ {Opt_delalloc, EXT4_MOUNT_DELALLOC,
+ MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
+ {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
+ MOPT_EXT4_ONLY | MOPT_CLEAR | MOPT_EXPLICIT},
+ {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
+ MOPT_EXT4_ONLY | MOPT_SET},
{Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
- EXT4_MOUNT_JOURNAL_CHECKSUM), MOPT_SET},
- {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_SET},
+ EXT4_MOUNT_JOURNAL_CHECKSUM),
+ MOPT_EXT4_ONLY | MOPT_SET},
+ {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
{Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
{Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
{Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
- {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_SET},
- {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT, MOPT_CLEAR},
+ {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
+ MOPT_NO_EXT2 | MOPT_SET},
+ {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
+ MOPT_NO_EXT2 | MOPT_CLEAR},
{Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
{Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
{Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
@@ -1451,9 +1462,10 @@ static const struct mount_opts {
{Opt_resgid, 0, MOPT_GTE0},
{Opt_journal_dev, 0, MOPT_GTE0},
{Opt_journal_ioprio, 0, MOPT_GTE0},
- {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_DATAJ},
- {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_DATAJ},
- {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA, MOPT_DATAJ},
+ {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
+ {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
+ {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
+ MOPT_NO_EXT2 | MOPT_DATAJ},
{Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
{Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
#ifdef CONFIG_EXT4_FS_POSIX_ACL
@@ -1531,6 +1543,17 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
return -1;
}
+ if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
+ ext4_msg(sb, KERN_ERR,
+ "Mount option \"%s\" incompatible with ext2", opt);
+ return -1;
+ }
+ if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
+ ext4_msg(sb, KERN_ERR,
+ "Mount option \"%s\" incompatible with ext3", opt);
+ return -1;
+ }
+
if (args->from && match_int(args, &arg))
return -1;
if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
--
1.7.12.rc0.22.gcdd159b
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