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Date: Thu, 14 Jun 2001 20:16:34 +0200
From: Andrea Arcangeli <andrea@suse.de>
To: Richard Henderson <rth@redhat.com>
Cc: Linus Torvalds <torvalds@transmeta.com>, Ingo Molnar <mingo@elte.hu>,
        linux-kernel@vger.kernel.org
Subject: Re: unregistered changes to the user<->kernel API
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On Thu, Jun 14, 2001 at 07:47:57PM +0200, Andrea Arcangeli wrote:
> On Thu, Jun 14, 2001 at 10:32:49AM -0700, Richard Henderson wrote:
> > within glibc, and (2) making these accesses slower since they
> > will be considered O_DIRECT after the change.
> 
> and then read/write will return -EINVAL which is life-threatening.
> O_DIRECT like rawio via /dev/raw imposes special buffer size and
> alignment (size multiple of softblocksize of the fs and softblocksize
> alignment, at max I can turn it down to hardblocksize without intensive
> changes and guaranteeing zerocopy [modulo bounce buffers on x86 of
> course]).
> 
> So in short at least glibc would need to be replaced...

in the meantime we solve this issue I released a new o_direct patch and
a 2.4.6pre3aa1 with O_DIRECT set like in the patches I sent to Linus at
the start of the thread. As soon as we take a definitive decision I will
update them. (in the meantime alpha users will at least be allowed again
to use O_SYNC with o_direct support applied ;)

Andrea