nilfs2: add norecovery mount option

This adds "norecovery" mount option which disables temporal write
access to read-only mounts or snapshots during mount/recovery.
Without this option, write access will be even performed for those
types of mounts; the temporal write access is needed to mount root
file system read-only after an unclean shutdown.

This option will be helpful when user wants to prevent any write
access to the device.

Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
Cc: Eric Sandeen <sandeen@redhat.com>
This commit is contained in:
Ryusuke Konishi
2009-11-20 03:28:01 +09:00
parent a057d2c011
commit 0234576d04
4 changed files with 39 additions and 3 deletions

View File

@@ -479,6 +479,8 @@ static int nilfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
seq_printf(seq, ",errors=panic");
if (nilfs_test_opt(sbi, STRICT_ORDER))
seq_printf(seq, ",order=strict");
if (nilfs_test_opt(sbi, NORECOVERY))
seq_printf(seq, ",norecovery");
return 0;
}
@@ -547,7 +549,7 @@ static const struct export_operations nilfs_export_ops = {
enum {
Opt_err_cont, Opt_err_panic, Opt_err_ro,
Opt_nobarrier, Opt_snapshot, Opt_order,
Opt_nobarrier, Opt_snapshot, Opt_order, Opt_norecovery,
Opt_err,
};
@@ -558,6 +560,7 @@ static match_table_t tokens = {
{Opt_nobarrier, "nobarrier"},
{Opt_snapshot, "cp=%u"},
{Opt_order, "order=%s"},
{Opt_norecovery, "norecovery"},
{Opt_err, NULL}
};
@@ -608,6 +611,9 @@ static int parse_options(char *options, struct super_block *sb)
sbi->s_snapshot_cno = option;
nilfs_set_opt(sbi, SNAPSHOT);
break;
case Opt_norecovery:
nilfs_set_opt(sbi, NORECOVERY);
break;
default:
printk(KERN_ERR
"NILFS: Unrecognized mount option \"%s\"\n", p);
@@ -863,6 +869,14 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data)
goto restore_opts;
}
if (!nilfs_valid_fs(nilfs)) {
printk(KERN_WARNING "NILFS (device %s): couldn't "
"remount because the filesystem is in an "
"incomplete recovery state.\n", sb->s_id);
err = -EINVAL;
goto restore_opts;
}
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
goto out;
if (*flags & MS_RDONLY) {