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Message-ID: <20160106152212.15218.qmail@stuge.se>
Date: Wed, 6 Jan 2016 16:22:12 +0100
From: Peter Stuge <peter@stuge.se>
To: "Steinar H. Gunderson" <sesse@google.com>
Cc: Christoph Hellwig <hch@infradead.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org,
        stern@rowland.harvard.edu
Subject: Re: [PATCH] Add support for usbfs zerocopy.
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	Christoph Hellwig <hch@infradead.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
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Steinar H. Gunderson wrote:
> > Our interface for zero copy reads/writes is O_DIRECT, and that requires
> > not special memory allocation, just proper alignment.
> 
> But that assumes you are using I/O using read()/write(). There's no way you
> can shoehorn USB isochronous reads into the read() interface, O_DIRECT or not.

How about aio?


//Peter