On Tue 28-05-13 13:19:01, Dmitry Monakhov wrote: > If filesystem was aborted we will return success > due to (sb->s_flags & MS_RDONLY) which is incorrect and > results in data loss. > In order to handle fs abort correctly we have to check > fs state once we discover that it is in MS_RDONLY state > > Test case: http://patchwork.ozlabs.org/patch/244297/ > Changes from V1: > - fix spelling > - fix smp_rmb()/debug order I've taken this patch to my tree with some minor spelling fixes. Honza > > Signed-off-by: Dmitry Monakhov <dmonakhov@xxxxxxxxxx> > --- > fs/ext3/fsync.c | 8 ++++++-- > fs/ext3/super.c | 13 ++++++++++++- > 2 files changed, 18 insertions(+), 3 deletions(-) > > diff --git a/fs/ext3/fsync.c b/fs/ext3/fsync.c > index b31dbd4..5412916 100644 > --- a/fs/ext3/fsync.c > +++ b/fs/ext3/fsync.c > @@ -48,9 +48,13 @@ int ext3_sync_file(struct file *file, loff_t start, loff_t end, int datasync) > > trace_ext3_sync_file_enter(file, datasync); > > - if (inode->i_sb->s_flags & MS_RDONLY) > + if (inode->i_sb->s_flags & MS_RDONLY) { > + /* Make shure that we read updated state */ > + smp_rmb(); > + if (EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS) > + return -EROFS; > return 0; > - > + } > ret = filemap_write_and_wait_range(inode->i_mapping, start, end); > if (ret) > goto out; > diff --git a/fs/ext3/super.c b/fs/ext3/super.c > index c8a4e17..b788bae 100644 > --- a/fs/ext3/super.c > +++ b/fs/ext3/super.c > @@ -174,6 +174,11 @@ static void ext3_handle_error(struct super_block *sb) > if (test_opt (sb, ERRORS_RO)) { > ext3_msg(sb, KERN_CRIT, > "error: remounting filesystem read-only"); > + /* > + * Make shure updated value of ->s_mount_state will be visiable > + * before ->s_flags update. > + */ > + smp_wmb(); > sb->s_flags |= MS_RDONLY; > } > ext3_commit_super(sb, es, 1); > @@ -291,8 +296,14 @@ void ext3_abort(struct super_block *sb, const char *function, > ext3_msg(sb, KERN_CRIT, > "error: remounting filesystem read-only"); > EXT3_SB(sb)->s_mount_state |= EXT3_ERROR_FS; > - sb->s_flags |= MS_RDONLY; > set_opt(EXT3_SB(sb)->s_mount_opt, ABORT); > + /* > + * Make shure updated value of ->s_mount_state will be visiable > + * before ->s_flags update. > + */ > + smp_wmb(); > + sb->s_flags |= MS_RDONLY; > + > if (EXT3_SB(sb)->s_journal) > journal_abort(EXT3_SB(sb)->s_journal, -EIO); > } > -- > 1.7.1 > -- Jan Kara <jack@xxxxxxx> SUSE Labs, CR -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
