ext4: do not allow journal_opts for fs w/o journal

It is appeared that we can pass journal related mount options and such options
be shown in /proc/mounts

Example:
#mkfs.ext4 -F /dev/vdb
#tune2fs -O ^has_journal /dev/vdb
#mount /dev/vdb /mnt/  -ocommit=20,journal_async_commit
#cat /proc/mounts  | grep /mnt
 /dev/vdb /mnt ext4 rw,relatime,journal_checksum,journal_async_commit,commit=20,data=ordered 0 0

But options:"journal_checksum,journal_async_commit,commit=20,data=ordered" has
nothing with reality because there is no journal at all.

This patch disallow following options for journalless configurations:
 - journal_checksum
 - journal_async_commit
 - commit=%ld
 - data={writeback,ordered,journal}

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index b1d04aa..750063f 100644 (file)
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1023,6 +1023,9 @@ struct ext4_inode_info {
 #define EXT4_MOUNT2_HURD_COMPAT                0x00000004 /* Support HURD-castrated
                                                      file systems */
 
+#define EXT4_MOUNT2_EXPLICIT_JOURNAL_CHECKSUM  0x00000008 /* User explicitly
+                                               specified journal checksum */
+
 #define clear_opt(sb, opt)             EXT4_SB(sb)->s_mount_opt &= \
                                                ~EXT4_MOUNT_##opt
 #define set_opt(sb, opt)               EXT4_SB(sb)->s_mount_opt |= \

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index db4be39..04d0f1b 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -1384,10 +1384,10 @@ static const struct mount_opts {
        {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
         MOPT_EXT4_ONLY | MOPT_CLEAR},
        {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
-        MOPT_EXT4_ONLY | MOPT_SET},
+        MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
        {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
                                    EXT4_MOUNT_JOURNAL_CHECKSUM),
-        MOPT_EXT4_ONLY | MOPT_SET},
+        MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
        {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},
@@ -1519,6 +1519,8 @@ static int handle_mount_opt(struct super_block *sb, char *opt, int token,
        if (m->flags & MOPT_EXPLICIT) {
                if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
                        set_opt2(sb, EXPLICIT_DELALLOC);
+               } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
+                       set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
                } else
                        return -1;
        }
@@ -3677,6 +3679,31 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
                       "suppressed and not mounted read-only");
                goto failed_mount_wq;
        } else {
+               /* Nojournal mode, all journal mount options are illegal */
+               if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
+                       ext4_msg(sb, KERN_ERR, "can't mount with "
+                                "journal_checksum, fs mounted w/o journal");
+                       goto failed_mount_wq;
+               }
+               if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
+                       ext4_msg(sb, KERN_ERR, "can't mount with "
+                                "journal_async_commit, fs mounted w/o journal");
+                       goto failed_mount_wq;
+               }
+               if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
+                       ext4_msg(sb, KERN_ERR, "can't mount with "
+                                "commit=%lu, fs mounted w/o journal",
+                                sbi->s_commit_interval / HZ);
+                       goto failed_mount_wq;
+               }
+               if (EXT4_MOUNT_DATA_FLAGS &
+                   (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
+                       ext4_msg(sb, KERN_ERR, "can't mount with "
+                                "data=, fs mounted w/o journal");
+                       goto failed_mount_wq;
+               }
+               sbi->s_def_mount_opt &= EXT4_MOUNT_JOURNAL_CHECKSUM;
+               clear_opt(sb, JOURNAL_CHECKSUM);
                clear_opt(sb, DATA_FLAGS);
                sbi->s_journal = NULL;
                needs_recovery = 0;