--- /dev/null
+From: Jeff Layton <jlayton-eUNUBHrolfbYtjvyW6yDsg@public.gmane.org>
+Subject: Re: [RFC][PATCH 06/10] cifs: define inode-level cache object and
+ register them
+Date: Fri, 25 Jun 2010 12:53:06 -0400
+Lines: 36
+Message-ID: <20100625125306.7f9b1966@tlielax.poochiereds.net>
+References: <4C24A606.5040001@suse.de>
+ <1277220214-3597-1-git-send-email-sjayaraman@suse.de>
+ <yes>
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+ <22697.1277470549@redhat.com>
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+Cc: Suresh Jayaraman <sjayaraman-l3A5Bk7waGM@public.gmane.org>,
+ Steve French <smfrench-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, linux-cifs-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
+ linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
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+To: David Howells <dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
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+
+On Fri, 25 Jun 2010 13:55:49 +0100
+David Howells <dhowells-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> wrote:
+
+> Suresh Jayaraman <sjayaraman-l3A5Bk7waGM@public.gmane.org> wrote:
+>
+> > I think the creation time is currently being ignored as we won't be able
+> > to accomodate in POSIX stat struct.
+>
+> The FS-Cache interface doesn't use the POSIX stat struct, but it could be
+> really useful to save it and use it for cache coherency inside the kernel.
+>
+> Out of interest, what does Samba do when it comes to generating a creation time
+> for UNIX where one does not exist?
+>
+
+(cc'ing samba-technical since we're talking about the create time)
+
+Looks like it mostly uses the ctime. IMO, the mtime would be a better
+choice since it changes less frequently, but I don't guess that it
+matters very much.
+
+I have a few patches that make the cifs_iget code do more stringent
+checks. One of those makes it use the create time like an i_generation
+field to guard against matching inodes that have the same number but
+that have undergone a delete/create cycle. They need a bit more testing
+but I'm planning to post them in time for 2.6.36.
+
+Because of how samba generates this number, it could be somewhat
+problematic to do this. What may save us though is that Linux<->Samba
+mostly uses unix extensions unless someone has specifically disabled
+them on either end. The unix extension calls don't generally send any
+sort of create time field, so we can't rely on it in those codepaths
+anyway.
+
+--
+Jeff Layton <jlayton-eUNUBHrolfbYtjvyW6yDsg@public.gmane.org>
+
+
projects / notmuch / blobdiff