From: Christoph Hellwig <hch@infradead.org>
To: Folkert van Heusden <folkert@vanheusden.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: zero-copy read() interface
Date: Thu, 18 Aug 2005 11:06:28 +0100 [thread overview]
Message-ID: <20050818100628.GA5629@infradead.org> (raw)
In-Reply-To: <20050818100151.GF12313@vanheusden.com>
On Thu, Aug 18, 2005 at 12:01:52PM +0200, Folkert van Heusden wrote:
> What about a zero-copy read-interface?
> An ioctl (or something) which enables the kernel to do dma directly to
> the userspace. Of course this should be limited to the root-user or a
> user with special capabilities (rights) since if a drive screws up, data
> from a different sector (or so) might end up in the proces' memory. Of
> course copying a sector from kernel- to userspace can be done pretty
> fast but i.m.h.o. all possible speedimprovements should be made unless
> unclean.
It's called O_DIRECT, and doesn't need root, just some alignment-constraints.
prev parent reply other threads:[~2005-08-18 10:06 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-08-18 10:01 zero-copy read() interface Folkert van Heusden
2005-08-18 10:05 ` Jörn Engel
2005-08-18 10:41 ` Folkert van Heusden
2005-08-18 13:13 ` Jörn Engel
2005-08-18 23:34 ` dean gaudet
2005-08-19 8:33 ` Jörn Engel
2005-08-21 9:01 ` Andrew Morton
2005-08-18 10:06 ` Christoph Hellwig [this message]
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