Re: [PATCH] xfs: unset MS_ACTIVE if mount fails

[Christoph Hellwig <hch@infradead.org>]

On Mon, Oct 17, 2016 at 10:38:49PM -0700, Darrick J. Wong wrote:
> In a way, yes.  We don't need to keep it on the LRU necessarily, we
> just need it not to think "Oh, this inode has i_nlink == 0 so we can
> truncate all the blocks and free the inode" prior to the end of bmap
> intent processing.
> 
> > I'd really prefer if we could just do it in our own ->drop_inode call
> > then instead of messing with MS_ACTIVE.
> 
> The difficulty here is that without MS_ACTIVE, the vfs will always
> evict the inode when i_count == 0.  I suppose bmap intent processing
> could bump up i_count and stash the inode somewhere to prevent the
> i_count from hitting zero until after we're done recovering the log...
> ...but otherwise I'm sorta stumped about how to do that.

Let me try to understand the issue here.

We get a final iput for an inode that recover once i_count hits zero.
We then want to hit the "if (!drop && (sb->s_flags & MS_ACTIVE)) {"
conditional there to add it to the lru, or at least not truncate it.
I guess for now we'll need MS_ACTIVE early here, yes.

So reluctantly:

Reviewed-by: Christoph Hellwig <hch@lst.de>