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Date: Fri, 20 Nov 2009 17:13:17 +0000
From: Jamie Lokier <jamie@shareable.org>
To: Jan Blunck <jblunck@suse.de>
Cc: linux-fsdevel@vger.kernel.org, Christoph Hellwig <hch@infradead.org>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Linux-Kernel Mailinglist <linux-kernel@vger.kernel.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Thomas Gleixner <tglx@linutronix.de>, jkacur@redhat.com,
       Arnd Bergmann <arnd@arndb.de>,
       =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker <fweisbec@gmail.com>,
       Willem Riede <osst@riede.org>,
       "James E.J. Bottomley" <James.Bottomley@suse.de>
Subject: Re: [PATCH 03/15] osst: Update ppos instead of using file->f_pos
Message-ID: <20091120171317.GH20634@shareable.org>
References: <1258735245-25826-1-git-send-email-jblunck@suse.de> <1258735245-25826-4-git-send-email-jblunck@suse.de>
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Jan Blunck wrote:
> osst_read()/osst_write() modify file->f_pos directly instead of the ppos
> given to them. The VFS later updates the file->f_pos and overwrites it
> with the value of ppos.

I notice st.c doesn't use or update file->f_pos (or *ppos), so
userspace probably won't be caring about f_pos from osst.c (they're
both SCSI tape drivers).  And osst.c doesn't use the value, it just
increases it with each transfer.  It doesn't even reset the value to
zero when rewinding the tape, so it's not that meaningful.

So how about just removing those modifications to file->f_pos from osst.c?

-- Jamie