On Wed, Jan 30, 2019 at 02:49:38PM +0800, zhangyi (F) wrote: > We do not unmap and clear dirty flag when forgetting a buffer without > journal or does not belongs to any transaction, so the invalid dirty > data may still be written to the disk later. It's fine if the > corresponding block is never used before the next mount, and it's also > fine that we invoke clean_bdev_aliases() related functions to unmap > the block device mapping when re-allocating such freed block as data > block. But this logic is somewhat fragile and risky that may lead to > data corruption if we forget to clean bdev aliases. So, It's better to > discard dirty data during forget time. > > We have been already handled all the cases of forgetting journalled > buffer, this patch deal with the remaining two cases. > > - buffer is not journalled yet, > - buffer is journalled but doesn't belongs to any transaction. > > We invoke __bforget() instead of __brelese() when forgetting an > un-journalled buffer in jbd2_journal_forget(). After this patch we can > remove all clean_bdev_aliases() related calls in ext4. > > Suggested-by: Jan Kara <jack@xxxxxxx> > Signed-off-by: zhangyi (F) <yi.zhang@xxxxxxxxxx> > Reviewed-by: Jan Kara <jack@xxxxxxx> Thanks, applied. - Ted
