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Date:   Mon, 28 Sep 2020 11:22:28 -0400 (EDT)
From:   Mikulas Patocka <mpatocka@redhat.com>
To:     Matthew Wilcox <willy@infradead.org>
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Subject: Re: NVFS XFS metadata (was: [PATCH] pmem: export the symbols
 __copy_user_flushcache and __copy_from_user_flushcache)
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On Thu, 24 Sep 2020, Mikulas Patocka wrote:

> On Tue, 22 Sep 2020, Matthew Wilcox wrote:
> 
> > > There is a small window when renamed inode is neither in source nor in 
> > > target directory. Fsck will reclaim such inode and add it to lost+found - 
> > > just like on EXT2.
> > 
> > ... ouch.  If you have to choose, it'd be better to link it to the second
> > directory then unlink it from the first one.  Then your fsck can detect
> > it has the wrong count and fix up the count (ie link it into both
> > directories rather than neither).
> 
> I admit that this is lame and I'll fix it. Rename is not so 
> performance-critical, so I can add a small journal for this.

Hi

I have implmemented transactions in nvfs and I use them for rename, 
setattr, atomic xattr replacement and for RENAME_EXCHANGE.

You can download the current version here:
git://leontynka.twibright.com/nvfs.git

Mikulas