Re: [Qemu-devel] [PATCH] virtio-scsi: actually honor sense_size from configuration space

[Paolo Bonzini]

Il 07/03/2014 08:40, Fam Zheng ha scritto:
> On Thu, 03/06 11:27, Paolo Bonzini wrote:
> > We were always truncating the sense size to 96 bytes.
> >
> > Signed-off-by: Paolo Bonzini <address@hidden>
> > ---
> >  hw/scsi/virtio-scsi.c | 4 +++-
> >  1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/scsi/virtio-scsi.c b/hw/scsi/virtio-scsi.c
> > index 6610b3a..b0d7517 100644
> > --- a/hw/scsi/virtio-scsi.c
> > +++ b/hw/scsi/virtio-scsi.c
> > @@ -304,6 +304,8 @@ static void virtio_scsi_command_complete(SCSIRequest *r, 
> > uint32_t status,
> >                                           size_t resid)
> >  {
> >      VirtIOSCSIReq *req = r->hba_private;
> > +    VirtIOSCSI *s = req->dev;
> > +    VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
> >      uint32_t sense_len;
> >
> >      if (r->io_canceled) {
> > @@ -317,7 +319,7 @@ static void virtio_scsi_command_complete(SCSIRequest *r, 
> > uint32_t status,
> >      } else {
> >          req->resp.cmd->resid = 0;
> >          sense_len = scsi_req_get_sense(r, req->resp.cmd->sense,
> > -                                       VIRTIO_SCSI_SENSE_SIZE);
> > +                                       vs->sense_size);
> >          req->resp.cmd->sense_len = tswap32(sense_len);
> >      }
> >      virtio_scsi_complete_req(req);
>
>
> Do we need to increase VIRTIO_SCSI_SENSE_SIZE as well?
>
>     $ git grep -n VIRTIO_SCSI_SENSE_SIZE
>     hw/scsi/virtio-scsi.c:463:    vs->sense_size = VIRTIO_SCSI_SENSE_SIZE;
>     hw/scsi/virtio-scsi.c:609:    s->sense_size = VIRTIO_SCSI_SENSE_SIZE;
>     include/hw/virtio/virtio-scsi.h:40:#define VIRTIO_SCSI_SENSE_SIZE  96

No, that's the default value and it's defined by the spec to be 96.

The OS can change it if they want.

Paolo