From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42208) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yik4r-0000nS-UN for qemu-devel@nongnu.org; Thu, 16 Apr 2015 09:43:34 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Yik4p-0002PY-9V for qemu-devel@nongnu.org; Thu, 16 Apr 2015 09:43:33 -0400 Received: from mail-wg0-x231.google.com ([2a00:1450:400c:c00::231]:35792) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Yik4p-0002PN-2L for qemu-devel@nongnu.org; Thu, 16 Apr 2015 09:43:31 -0400 Received: by wgyo15 with SMTP id o15so81420598wgy.2 for ; Thu, 16 Apr 2015 06:43:30 -0700 (PDT) Sender: Paolo Bonzini Message-ID: <552FBC7E.8050806@redhat.com> Date: Thu, 16 Apr 2015 15:43:26 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Subject: Re: [Qemu-devel] How to modify QEMU source to read the bus for SATA directly? List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Teoh , qemu-devel@nongnu.org On 16/04/2015 15:25, Peter Teoh wrote: > > Now my question is: Is it possible to modify the QEMU source code, or > pass in the correct parameters in the command line, so as provide direct > I/O access from the QEMU guest all the way to the underlying host's AHCI > sata bus (based on my AMD's hardware configuration as above)? You can use PCI passthrough and let the guest use the whole SATA bus, if you have another way to access other disks on the same bus (e.g. boot from a USB stick or access the filesystems on NFS). Or you can use SCSI passthrough and pass the /dev/sdX device to the guest, e.g. -device virtio-scsi-pci -drive if=none,file=/dev/sdb,id=sdb,cache=none,format=raw -device scsi-block,drive=sdb The guest then will talk to the host's ATA->SCSI translation layer, and will be able to send raw ATA commands via the ATA PASSTHROUGH command. Paolo