Re: [Qemu-devel] How to modify QEMU source to read the bus for SATA directly?

[Paolo Bonzini <pbonzini@redhat.com>]

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