RE: [Xen-devel] Userspace PIO access under xen

To:	"Michael S. Tsirkin" <mst@xxxxxxxxxxxxxx>
Subject:	RE: [Xen-devel] Userspace PIO access under xen
From:	"Ian Pratt" <m+Ian.Pratt@xxxxxxxxxxxx>
Date:	Mon, 25 Jul 2005 13:22:52 +0100
Cc:	Dror Goldenberg <gdror@xxxxxxxxxxxxxx>, xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date:	Mon, 25 Jul 2005 12:21:25 +0000
Envelope-to:	www-data@xxxxxxxxxxxxxxxxxxx
List-help:	<mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id:	Xen developer discussion <xen-devel.lists.xensource.com>
List-post:	<mailto:xen-devel@lists.xensource.com>
List-subscribe:	<http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe:	<http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
Sender:	xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
Thread-index:	AcWREbVqVOhnTgyfRoClwSOd61/5OgAAXQjQ
Thread-topic:	[Xen-devel] Userspace PIO access under xen

 

> You can also use /proc/bus/pci/ for this, the difference is 
> that you have to give full bus address to /proc/bus/pci/ , 
> while /sys/bus/pci/devices/ needs an offset within the resource.
> 
> > Change pci_mmap_page_range in arch/xen/arch/pci/i386.c to use 
> > io_remap_pfn_range
> 
> I've written a small kernel module to map PIO to userspace 
> using remap_page_range, and that doesnt seem to work, either.

You have to use io_remap_pfn_range for mapping IO space. Using
remap_pfn_range is technically a bug in the i386 code.

I believe the pfn_range functions are preferred over page_range
functions anyhow.

Ian

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel

WARNING - OLD ARCHIVES

xen-devel

RE: [Xen-devel] Userspace PIO access under xen