From: jtk@us.ibm.com (John T. Kohl)
To: Josef Sipek <jsipek@fsl.cs.sunysb.edu>, linux-fsdevel@vger.kernel.org
Subject: Re: Wrapper fs Code (wrapfs)
Date: 07 Aug 2006 16:35:23 -0400 [thread overview]
Message-ID: <6coduw708k.fsf@sumu.lexma.ibm.com> (raw)
In-Reply-To: <20060804205715.GA18719@filer.fsl.cs.sunysb.edu>
>>>>> "Josef" == Josef Sipek <jsipek@fsl.cs.sunysb.edu> writes:
Josef> That is an artifact of how the Linux VFS works. When you modify a
Josef> file though wrapfs (or any other stackable file system) the
Josef> wrapfs code gets called. It then calls the lower file system code
Josef> on your behalf. When you modify the lower file directly, ext3
Josef> gets the called, but since Linux has no way for this change to be
Josef> announced up the stack, wrapfs happily uses the old, cached
Josef> data. If you have ideas about how to solve this, please share
Josef> them - right now, there is a lot of work being done to get
Josef> Unionfs (ours) and eCryptfs into the vanilla linux kernel.
While constructed for a vnode system, the ideas in a set of
Ficus-related papers and theses could be helpful here. This is John
Heidemann's PhD thesis on the topic (covers necessary VM designs,
callbacks, etc.):
http://www.isi.edu/people/johnh/PAPERS/Heidemann95e.html
--
John Kohl
Senior Software Engineer - Rational Software - IBM Software Group
Lexington, Massachusetts, USA
jtk@us.ibm.com
<http://www.ibm.com/software/rational/>
next prev parent reply other threads:[~2006-08-07 20:35 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
2006-08-04 6:09 Wrapper fs Code (wrapfs) UZAIR LAKHANI
2006-08-04 20:57 ` Josef Sipek
2006-08-07 4:50 ` UZAIR LAKHANI
2006-08-07 6:59 ` Josef Sipek
2006-08-08 7:57 ` UZAIR LAKHANI
2006-08-08 15:41 ` Josef Sipek
2006-08-09 10:53 ` UZAIR LAKHANI
2006-08-07 20:35 ` John T. Kohl [this message]
2006-08-07 21:24 ` Josef Sipek
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=6coduw708k.fsf@sumu.lexma.ibm.com \
--to=jtk@us.ibm.com \
--cc=jsipek@fsl.cs.sunysb.edu \
--cc=linux-fsdevel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.