From: Andreas Dilger <adilger@sun.com>
Subject: Re: Do we need dump for ext4?
Date: Thu, 28 Aug 2008 17:14:06 -0600
Message-ID: <20080828231406.GT3392@webber.adilger.int>
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Cc: Ric Wheeler <rwheeler@redhat.com>,
	Eric Sandeen <sandeen@redhat.com>,
	ext4 development <linux-ext4@vger.kernel.org>
To: Theodore Tso <tytso@mit.edu>
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On Aug 28, 2008  18:34 -0400, Theodore Ts'o wrote:
> It's fine, because according to POSIX it's undefined what happens to
> files that are created or deleted after the last opendir() or
> rewindir().  So basically, the b-tree is attached to the opendir, and
> we discard it and re-create it if we ever seek to the beginning of the
> directory.

... presumably only if the directory has been modified in the meantime?
It seems like this is missing from the ext3_dx_readdir() code, and could
be easily achieved by checking inode->i_version vs. filp->f_version or
similar.  It looks like this is checked later on, but by that time we've
already discarded everything.


Cheers, Andreas
--
Andreas Dilger
Sr. Staff Engineer, Lustre Group
Sun Microsystems of Canada, Inc.