From: Paul Brook <paul@codesourcery.com>
To: qemu-devel@nongnu.org
Cc: Anthony Liguori <aliguori@us.ibm.com>,
Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: [Qemu-devel] Re: [PATCH 2/3] virtio network device
Date: Wed, 5 Dec 2007 17:44:02 +0000 [thread overview]
Message-ID: <200712051744.03916.paul@codesourcery.com> (raw)
In-Reply-To: <4756DD7A.8070008@us.ibm.com>
> > Actually according to qemu's standard, one should use
> > cpu_physical_memory_write/ cpu_physical_memory_read functions.
> > This is true also for reading the ring values.
>
> Yes, and unfortunately, cpu_physical_memory_{read,write} are copy
> interfaces. We really don't want that for high speed I/O.
I really don't like doing direct access to guest ram without implementing a
proper API for zero-copy/scatter-gather access. There was a list thread about
this not so long ago.
Paul
next prev parent reply other threads:[~2007-12-05 17:44 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2007-12-04 21:54 [Qemu-devel] [PATCH 2/3] virtio network device Anthony Liguori
2007-12-04 22:12 ` Anthony Liguori
2007-12-04 23:49 ` [Qemu-devel] " Dor Laor
2007-12-05 17:18 ` Anthony Liguori
2007-12-05 17:44 ` Paul Brook [this message]
2007-12-05 20:20 ` Anthony Liguori
2007-12-06 9:27 ` Jamie Lokier
2007-12-08 13:22 ` Paul Brook
2007-12-08 14:09 ` Jamie Lokier
2007-12-08 16:45 ` Paul Brook
2007-12-08 19:52 ` Blue Swirl
2007-12-08 21:55 ` Jamie Lokier
2007-12-08 22:02 ` Anthony Liguori
2007-12-12 1:24 ` Rusty Russell
2007-12-12 1:40 ` Anthony Liguori
2007-12-18 2:31 ` Rusty Russell
2007-12-08 21:59 ` Anthony Liguori
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