nilfs2: reject incompatible filesystem
This forces nilfs to check compatibility of feature flags so as to
reject a filesystem with unknown features when it mounts or remounts
the filesystem.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c
index f2efc8c..da67b56 100644
--- a/fs/nilfs2/the_nilfs.c
+++ b/fs/nilfs2/the_nilfs.c
@@ -385,11 +385,23 @@
goto skip_recovery;
if (s_flags & MS_RDONLY) {
+ __u64 features;
+
if (nilfs_test_opt(sbi, NORECOVERY)) {
printk(KERN_INFO "NILFS: norecovery option specified. "
"skipping roll-forward recovery\n");
goto skip_recovery;
}
+ features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) &
+ ~NILFS_FEATURE_COMPAT_RO_SUPP;
+ if (features) {
+ printk(KERN_ERR "NILFS: couldn't proceed with "
+ "recovery because of unsupported optional "
+ "features (%llx)\n",
+ (unsigned long long)features);
+ err = -EROFS;
+ goto failed_unload;
+ }
if (really_read_only) {
printk(KERN_ERR "NILFS: write access "
"unavailable, cannot proceed.\n");
@@ -644,6 +656,10 @@
if (err)
goto out;
+ err = nilfs_check_feature_compatibility(sb, sbp);
+ if (err)
+ goto out;
+
blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size);
if (sb->s_blocksize != blocksize &&
!sb_set_blocksize(sb, blocksize)) {
@@ -669,6 +685,10 @@
if (err)
goto failed_sbh;
+ err = nilfs_check_feature_compatibility(sb, sbp);
+ if (err)
+ goto failed_sbh;
+
blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size);
if (sb->s_blocksize != blocksize) {
int hw_blocksize = bdev_logical_block_size(sb->s_bdev);
