diff options
Diffstat (limited to 'fs/nilfs2/super.c')
| -rw-r--r-- | fs/nilfs2/super.c | 39 |
1 files changed, 39 insertions, 0 deletions
diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 164457316df..26078b3407c 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -790,6 +790,30 @@ int nilfs_store_magic_and_option(struct super_block *sb, return !parse_options(data, sb, 0) ? -EINVAL : 0 ; } +int nilfs_check_feature_compatibility(struct super_block *sb, + struct nilfs_super_block *sbp) +{ + __u64 features; + + features = le64_to_cpu(sbp->s_feature_incompat) & + ~NILFS_FEATURE_INCOMPAT_SUPP; + if (features) { + printk(KERN_ERR "NILFS: couldn't mount because of unsupported " + "optional features (%llx)\n", + (unsigned long long)features); + return -EINVAL; + } + features = le64_to_cpu(sbp->s_feature_compat_ro) & + ~NILFS_FEATURE_COMPAT_RO_SUPP; + if (!(sb->s_flags & MS_RDONLY) && features) { + printk(KERN_ERR "NILFS: couldn't mount RDWR because of " + "unsupported optional features (%llx)\n", + (unsigned long long)features); + return -EINVAL; + } + return 0; +} + /** * nilfs_fill_super() - initialize a super block instance * @sb: super_block @@ -984,11 +1008,26 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data) nilfs_cleanup_super(sbi); up_write(&nilfs->ns_sem); } else { + __u64 features; + /* * Mounting a RDONLY partition read-write, so reread and * store the current valid flag. (It may have been changed * by fsck since we originally mounted the partition.) */ + down_read(&nilfs->ns_sem); + features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & + ~NILFS_FEATURE_COMPAT_RO_SUPP; + up_read(&nilfs->ns_sem); + if (features) { + printk(KERN_WARNING "NILFS (device %s): couldn't " + "remount RDWR because of unsupported optional " + "features (%llx)\n", + sb->s_id, (unsigned long long)features); + err = -EROFS; + goto restore_opts; + } + sb->s_flags &= ~MS_RDONLY; err = nilfs_attach_segment_constructor(sbi); |