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    SubjectRe: virtio scsi host draft specification, v3
    > If requests are placed on arbitrary queues you'll inevitably run on
    > locking issues to ensure strict request ordering.
    > I would add here:
    >
    > If a device uses more than one queue it is the responsibility of the
    > device to ensure strict request ordering.

    Applied with s/device/guest/g.

    > Please do not rely in bus/target/lun here. These are leftovers from
    > parallel SCSI and do not have any meaning on modern SCSI
    > implementation (eg FC or SAS). Rephrase that to
    >
    > The lun field is the Logical Unit Number as defined in SAM.

    Ok.

    > > The status byte is written by the device to be the SCSI status
    > > code.
    >
    > ?? I doubt that exists. Make that:
    >
    > The status byte is written by the device to be the status code as
    > defined in SAM.

    Ok.

    > > The response byte is written by the device to be one of the
    > > following:
    > >
    > > - VIRTIO_SCSI_S_OK when the request was completed and the
    > > status byte
    > > is filled with a SCSI status code (not necessarily "GOOD").
    > >
    > > - VIRTIO_SCSI_S_UNDERRUN if the content of the CDB requires
    > > transferring
    > > more data than is available in the data buffers.
    > >
    > > - VIRTIO_SCSI_S_ABORTED if the request was cancelled due to a
    > > reset
    > > or another task management function.
    > >
    > > - VIRTIO_SCSI_S_FAILURE for other host or guest error. In
    > > particular,
    > > if neither dataout nor datain is empty, and the
    > > VIRTIO_SCSI_F_INOUT
    > > feature has not been negotiated, the request will be
    > > immediately
    > > returned with a response equal to VIRTIO_SCSI_S_FAILURE.
    > >
    > And, of course:
    >
    > VIRTIO_SCSI_S_DISCONNECT if the request could not be processed due
    > to a communication failure (eg device was removed or could not be
    > reached).

    Ok.

    > This specification implies a strict one-to-one mapping between host
    > and target. IE there is no way of specifying more than one target
    > per host.

    Actually no, the intention is to use hierarchical LUNs to support
    more than one target per host.

    Paolo


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