Re: [PATCH v6 1/5] vhost-user-common: send get_inflight_fd once

[Li Feng <fengli@smartx.com>]

On Fri, Sep 29, 2023 at 8:55 AM Raphael Norwitz
<raphael.norwitz@nutanix.com> wrote:
>
>
>
> > On Sep 22, 2023, at 7:46 AM, Li Feng <fengli@smartx.com> wrote:
> >
> > Currently the get_inflight_fd will be sent every time the device is started, and
> > the backend will allocate shared memory to save the inflight state. If the
> > backend finds that it receives the second get_inflight_fd, it will release the
> > previous shared memory, which breaks inflight working logic.
> >
> > This patch is a preparation for the following patches.
>
> This looks identical to the v3 patch I reviewed? If I’ve missed something can you please point it out?
Yes, nothing changed in this patch.

>
>
> > Signed-off-by: Li Feng <fengli@smartx.com>
> > ---
> > hw/scsi/vhost-scsi-common.c | 37 ++++++++++++++++++-------------------
> > 1 file changed, 18 insertions(+), 19 deletions(-)
> >
> > diff --git a/hw/scsi/vhost-scsi-common.c b/hw/scsi/vhost-scsi-common.c
> > index a06f01af26..a61cd0e907 100644
> > --- a/hw/scsi/vhost-scsi-common.c
> > +++ b/hw/scsi/vhost-scsi-common.c
> > @@ -52,20 +52,28 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> >
> >     vsc->dev.acked_features = vdev->guest_features;
> >
> > -    assert(vsc->inflight == NULL);
> > -    vsc->inflight = g_new0(struct vhost_inflight, 1);
> > -    ret = vhost_dev_get_inflight(&vsc->dev,
> > -                                 vs->conf.virtqueue_size,
> > -                                 vsc->inflight);
> > +    ret = vhost_dev_prepare_inflight(&vsc->dev, vdev);
> >     if (ret < 0) {
> > -        error_report("Error get inflight: %d", -ret);
> > +        error_report("Error setting inflight format: %d", -ret);
> >         goto err_guest_notifiers;
> >     }
> >
> > -    ret = vhost_dev_set_inflight(&vsc->dev, vsc->inflight);
> > -    if (ret < 0) {
> > -        error_report("Error set inflight: %d", -ret);
> > -        goto err_guest_notifiers;
> > +    if (vsc->inflight) {
> > +        if (!vsc->inflight->addr) {
> > +            ret = vhost_dev_get_inflight(&vsc->dev,
> > +                                        vs->conf.virtqueue_size,
> > +                                        vsc->inflight);
> > +            if (ret < 0) {
> > +                error_report("Error getting inflight: %d", -ret);
> > +                goto err_guest_notifiers;
> > +            }
> > +        }
> > +
> > +        ret = vhost_dev_set_inflight(&vsc->dev, vsc->inflight);
> > +        if (ret < 0) {
> > +            error_report("Error setting inflight: %d", -ret);
> > +            goto err_guest_notifiers;
> > +        }
> >     }
> >
> >     ret = vhost_dev_start(&vsc->dev, vdev, true);
> > @@ -85,9 +93,6 @@ int vhost_scsi_common_start(VHostSCSICommon *vsc)
> >     return ret;
> >
> > err_guest_notifiers:
> > -    g_free(vsc->inflight);
> > -    vsc->inflight = NULL;
> > -
> >     k->set_guest_notifiers(qbus->parent, vsc->dev.nvqs, false);
> > err_host_notifiers:
> >     vhost_dev_disable_notifiers(&vsc->dev, vdev);
> > @@ -111,12 +116,6 @@ void vhost_scsi_common_stop(VHostSCSICommon *vsc)
> >     }
> >     assert(ret >= 0);
> >
> > -    if (vsc->inflight) {
> > -        vhost_dev_free_inflight(vsc->inflight);
> > -        g_free(vsc->inflight);
> > -        vsc->inflight = NULL;
> > -    }
> > -
> >     vhost_dev_disable_notifiers(&vsc->dev, vdev);
> > }
> >
> > --
> > 2.41.0
> >
>