From: Eugenio Perez Martin <eperezma@redhat.com>
To: Jason Wang <jasowang@redhat.com>
Cc: netdev <netdev@vger.kernel.org>,
linux-kernel <linux-kernel@vger.kernel.org>,
virtualization <virtualization@lists.linux-foundation.org>,
kvm <kvm@vger.kernel.org>, "Michael S. Tsirkin" <mst@redhat.com>,
Parav Pandit <parav@nvidia.com>,
Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
Cindy Lu <lulu@redhat.com>, "Kamde, Tanuj" <tanuj.kamde@amd.com>,
Si-Wei Liu <si-wei.liu@oracle.com>,
"Uminski, Piotr" <Piotr.Uminski@intel.com>,
habetsm.xilinx@gmail.com, "Dawar, Gautam" <gautam.dawar@amd.com>,
Pablo Cascon Katchadourian <pabloc@xilinx.com>,
Zhu Lingshan <lingshan.zhu@intel.com>,
Laurent Vivier <lvivier@redhat.com>,
Longpeng <longpeng2@huawei.com>,
Dinan Gunawardena <dinang@xilinx.com>,
Martin Petrus Hubertus Habets <martinh@xilinx.com>,
Martin Porter <martinpo@xilinx.com>, Eli Cohen <elic@nvidia.com>,
ecree.xilinx@gmail.com,
Wu Zongyong <wuzongyong@linux.alibaba.com>,
Stefano Garzarella <sgarzare@redhat.com>,
Dan Carpenter <dan.carpenter@oracle.com>,
Harpreet Singh Anand <hanand@xilinx.com>,
Xie Yongji <xieyongji@bytedance.com>,
Zhang Min <zhang.min9@zte.com.cn>
Subject: Re: [PATCH v6 2/4] vhost-vdpa: introduce SUSPEND backend feature bit
Date: Fri, 8 Jul 2022 13:44:57 +0200 [thread overview]
Message-ID: <CAJaqyWdciXkbtpBmGugDsr+0Nh3X50r2Fa5i9Yk2NyQaXBLKtg@mail.gmail.com> (raw)
In-Reply-To: <CACGkMEtNC=4KeigQXr4NuaiuVGkxK2ruQTk6-Fbr3B1MqHieTA@mail.gmail.com>
On Wed, Jun 29, 2022 at 6:12 AM Jason Wang <jasowang@redhat.com> wrote:
>
> On Fri, Jun 24, 2022 at 12:08 AM Eugenio Pérez <eperezma@redhat.com> wrote:
> >
> > Userland knows if it can suspend the device or not by checking this feature
> > bit.
> >
> > It's only offered if the vdpa driver backend implements the suspend()
> > operation callback, and to offer it or userland to ack it if the backend
> > does not offer that callback is an error.
> >
> > Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
> > ---
> > drivers/vhost/vdpa.c | 16 +++++++++++++++-
> > include/uapi/linux/vhost_types.h | 2 ++
> > 2 files changed, 17 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
> > index 23dcbfdfa13b..3d636e192061 100644
> > --- a/drivers/vhost/vdpa.c
> > +++ b/drivers/vhost/vdpa.c
> > @@ -347,6 +347,14 @@ static long vhost_vdpa_set_config(struct vhost_vdpa *v,
> > return 0;
> > }
> >
> > +static bool vhost_vdpa_can_suspend(const struct vhost_vdpa *v)
> > +{
> > + struct vdpa_device *vdpa = v->vdpa;
> > + const struct vdpa_config_ops *ops = vdpa->config;
> > +
> > + return ops->suspend;
> > +}
> > +
> > static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep)
> > {
> > struct vdpa_device *vdpa = v->vdpa;
> > @@ -577,7 +585,11 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
> > if (cmd == VHOST_SET_BACKEND_FEATURES) {
> > if (copy_from_user(&features, featurep, sizeof(features)))
> > return -EFAULT;
> > - if (features & ~VHOST_VDPA_BACKEND_FEATURES)
> > + if (features & ~(VHOST_VDPA_BACKEND_FEATURES |
> > + BIT_ULL(VHOST_BACKEND_F_SUSPEND)))
> > + return -EOPNOTSUPP;
> > + if ((features & BIT_ULL(VHOST_BACKEND_F_SUSPEND)) &&
> > + !vhost_vdpa_can_suspend(v))
>
> Do we need to advertise this to the management?
>
Not sure if I follow, the feature bit is not exposed if the backend
cannot suspend.
Thanks!
> Thanks
>
> > return -EOPNOTSUPP;
> > vhost_set_backend_features(&v->vdev, features);
> > return 0;
> > @@ -628,6 +640,8 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
> > break;
> > case VHOST_GET_BACKEND_FEATURES:
> > features = VHOST_VDPA_BACKEND_FEATURES;
> > + if (vhost_vdpa_can_suspend(v))
> > + features |= BIT_ULL(VHOST_BACKEND_F_SUSPEND);
> > if (copy_to_user(featurep, &features, sizeof(features)))
> > r = -EFAULT;
> > break;
> > diff --git a/include/uapi/linux/vhost_types.h b/include/uapi/linux/vhost_types.h
> > index 634cee485abb..1bdd6e363f4c 100644
> > --- a/include/uapi/linux/vhost_types.h
> > +++ b/include/uapi/linux/vhost_types.h
> > @@ -161,5 +161,7 @@ struct vhost_vdpa_iova_range {
> > * message
> > */
> > #define VHOST_BACKEND_F_IOTLB_ASID 0x3
> > +/* Device can be suspended */
> > +#define VHOST_BACKEND_F_SUSPEND 0x4
> >
> > #endif
> > --
> > 2.31.1
> >
>
next prev parent reply other threads:[~2022-07-08 11:45 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-06-23 16:07 [PATCH v6 0/4] Implement vdpasim suspend operation Eugenio Pérez
2022-06-23 16:07 ` [PATCH v6 1/4] vdpa: Add " Eugenio Pérez
2022-06-28 13:39 ` Stefano Garzarella
2022-07-08 11:28 ` Eugenio Perez Martin
2022-06-29 4:10 ` Jason Wang
2022-07-08 11:30 ` Eugenio Perez Martin
2022-07-12 8:04 ` Jason Wang
2022-06-23 16:07 ` [PATCH v6 2/4] vhost-vdpa: introduce SUSPEND backend feature bit Eugenio Pérez
2022-06-28 13:43 ` Stefano Garzarella
2022-07-08 11:38 ` Eugenio Perez Martin
2022-07-08 13:51 ` Stefano Garzarella
2022-06-29 4:12 ` Jason Wang
2022-07-08 11:44 ` Eugenio Perez Martin [this message]
2022-06-23 16:07 ` [PATCH v6 3/4] vhost-vdpa: uAPI to suspend the device Eugenio Pérez
2022-06-28 13:44 ` Stefano Garzarella
2022-07-08 11:47 ` Eugenio Perez Martin
2022-06-29 4:15 ` Jason Wang
2022-07-08 11:53 ` Eugenio Perez Martin
2022-07-12 8:08 ` Jason Wang
2022-06-23 16:07 ` [PATCH v6 4/4] vdpa_sim: Implement suspend vdpa op Eugenio Pérez
2022-06-29 4:18 ` Jason Wang
2022-07-08 12:20 ` Eugenio Perez Martin
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=CAJaqyWdciXkbtpBmGugDsr+0Nh3X50r2Fa5i9Yk2NyQaXBLKtg@mail.gmail.com \
--to=eperezma@redhat.com \
--cc=Piotr.Uminski@intel.com \
--cc=christophe.jaillet@wanadoo.fr \
--cc=dan.carpenter@oracle.com \
--cc=dinang@xilinx.com \
--cc=ecree.xilinx@gmail.com \
--cc=elic@nvidia.com \
--cc=gautam.dawar@amd.com \
--cc=habetsm.xilinx@gmail.com \
--cc=hanand@xilinx.com \
--cc=jasowang@redhat.com \
--cc=kvm@vger.kernel.org \
--cc=lingshan.zhu@intel.com \
--cc=linux-kernel@vger.kernel.org \
--cc=longpeng2@huawei.com \
--cc=lulu@redhat.com \
--cc=lvivier@redhat.com \
--cc=martinh@xilinx.com \
--cc=martinpo@xilinx.com \
--cc=mst@redhat.com \
--cc=netdev@vger.kernel.org \
--cc=pabloc@xilinx.com \
--cc=parav@nvidia.com \
--cc=sgarzare@redhat.com \
--cc=si-wei.liu@oracle.com \
--cc=tanuj.kamde@amd.com \
--cc=virtualization@lists.linux-foundation.org \
--cc=wuzongyong@linux.alibaba.com \
--cc=xieyongji@bytedance.com \
--cc=zhang.min9@zte.com.cn \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).