Re: [PATCH] virtio_mmio: add suspend and resume calls for virtio_mmio devices
From: Jason Wang
Date: Thu Aug 10 2023 - 22:13:08 EST
On Fri, Aug 11, 2023 at 3:45 AM Michael S. Tsirkin <mst@xxxxxxxxxx> wrote:
>
> On Fri, Jul 28, 2023 at 12:31:27PM +0530, Anvesh Jain P wrote:
> > Handle suspend and resume calls for virtio mmio devices from
> > PM core. Expose these notifications to virtio drivers that can quiesce and
> > resume vq operations. Update virtio pm ops to handle freeze& restore and
> > suspend & resume callbacks separately.
> >
> > Signed-off-by: Anvesh Jain P <quic_ajainp@xxxxxxxxxxx>
> > Signed-off-by: Venkata Rao Kakani <quic_vkakani@xxxxxxxxxxx>
>
> okey but what is the motivation? does this addition of 200 LOC
> achieve something new? what is the issue fixed here?
+1
And I think we need an example that can use the new ops.
Thanks
>
>
> > ---
> > drivers/virtio/virtio.c | 112 +++++++++++++++++++++++++++++++++++
> > drivers/virtio/virtio_mmio.c | 50 +++++++++++++++-
> > include/linux/virtio.h | 12 ++++
> > 3 files changed, 173 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
> > index 3893dc29eb26..c6f25a267600 100644
> > --- a/drivers/virtio/virtio.c
> > +++ b/drivers/virtio/virtio.c
> > @@ -551,6 +551,118 @@ int virtio_device_restore(struct virtio_device *dev)
> > return ret;
> > }
> > EXPORT_SYMBOL_GPL(virtio_device_restore);
> > +
> > +int virtio_device_suspend(struct virtio_device *dev)
> > +{
> > + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
> > +
> > + virtio_config_disable(dev);
> > +
> > + dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
> > +
> > + if (drv && drv->suspend)
> > + return drv->suspend(dev);
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(virtio_device_suspend);
> > +
> > +int virtio_device_resume(struct virtio_device *dev)
> > +{
> > + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
> > + int ret;
> > +
> > + if (drv && drv->resume) {
> > + ret = drv->resume(dev);
> > + if (ret)
> > + goto err;
> > +
> > + if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))
> > + virtio_device_ready(dev);
> > +
> > + virtio_config_enable(dev);
> > + }
> > +
> > + return 0;
> > +err:
> > + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(virtio_device_resume);
> > +
> > +int virtio_device_suspend_late(struct virtio_device *dev)
> > +{
> > + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
> > +
> > + virtio_config_disable(dev);
> > +
> > + dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
> > +
> > + if (drv && drv->suspend_late)
> > + return drv->suspend_late(dev);
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(virtio_device_suspend_late);
> > +
> > +int virtio_device_resume_early(struct virtio_device *dev)
> > +{
> > + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
> > + int ret;
> > +
> > + if (drv && drv->resume_early) {
> > + ret = drv->resume_early(dev);
> > + if (ret)
> > + goto err;
> > + if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))
> > + virtio_device_ready(dev);
> > +
> > + virtio_config_enable(dev);
> > + }
> > +
> > + return 0;
> > +err:
> > + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(virtio_device_resume_early);
> > +
> > +int virtio_device_suspend_noirq(struct virtio_device *dev)
> > +{
> > + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
> > +
> > + virtio_config_disable(dev);
> > +
> > + dev->failed = dev->config->get_status(dev) & VIRTIO_CONFIG_S_FAILED;
> > +
> > + if (drv && drv->suspend_noirq)
> > + return drv->suspend_noirq(dev);
> > +
> > + return 0;
> > +}
> > +EXPORT_SYMBOL_GPL(virtio_device_suspend_noirq);
> > +
> > +int virtio_device_resume_noirq(struct virtio_device *dev)
> > +{
> > + struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
> > + int ret;
> > +
> > + if (drv && drv->resume_noirq) {
> > + ret = drv->resume_noirq(dev);
> > + if (ret)
> > + goto err;
> > + if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))
> > + virtio_device_ready(dev);
> > +
> > + virtio_config_enable(dev);
> > + }
> > +
> > + return 0;
> > +err:
> > + virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
> > + return ret;
> > +}
> > +EXPORT_SYMBOL_GPL(virtio_device_resume_noirq);
> > #endif
> >
> > static int virtio_init(void)
> > diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c
> > index a46a4a29e929..9385c7e65da9 100644
> > --- a/drivers/virtio/virtio_mmio.c
> > +++ b/drivers/virtio/virtio_mmio.c
> > @@ -596,9 +596,57 @@ static int virtio_mmio_restore(struct device *dev)
> >
> > return virtio_device_restore(&vm_dev->vdev);
> > }
> > +static int virtio_mmio_suspend(struct device *dev)
> > +{
> > + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev);
> > +
> > + return virtio_device_suspend(&vm_dev->vdev);
> > +}
> > +
> > +static int virtio_mmio_resume(struct device *dev)
> > +{
> > + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev);
> > +
> > + return virtio_device_resume(&vm_dev->vdev);
> > +}
> > +
> > +static int virtio_mmio_suspend_late(struct device *dev)
> > +{
> > + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev);
> > +
> > + return virtio_device_suspend_late(&vm_dev->vdev);
> > +}
> > +
> > +static int virtio_mmio_resume_early(struct device *dev)
> > +{
> > + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev);
> > +
> > + return virtio_device_resume_early(&vm_dev->vdev);
> > +}
> > +
> > +static int virtio_mmio_suspend_noirq(struct device *dev)
> > +{
> > + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev);
> > +
> > + return virtio_device_suspend_noirq(&vm_dev->vdev);
> > +}
> > +
> > +static int virtio_mmio_resume_noirq(struct device *dev)
> > +{
> > + struct virtio_mmio_device *vm_dev = dev_get_drvdata(dev);
> > +
> > + return virtio_device_resume_noirq(&vm_dev->vdev);
> > +}
> >
> > static const struct dev_pm_ops virtio_mmio_pm_ops = {
> > - SET_SYSTEM_SLEEP_PM_OPS(virtio_mmio_freeze, virtio_mmio_restore)
> > + .freeze = virtio_mmio_freeze,
> > + .restore = virtio_mmio_restore,
> > + .suspend = virtio_mmio_suspend,
> > + .resume = virtio_mmio_resume,
> > + .suspend_late = virtio_mmio_suspend_late,
> > + .resume_early = virtio_mmio_resume_early,
> > + .suspend_noirq = virtio_mmio_suspend_noirq,
> > + .resume_noirq = virtio_mmio_resume_noirq,
> > };
> > #endif
> >
> > diff --git a/include/linux/virtio.h b/include/linux/virtio.h
> > index de6041deee37..e88b321408e9 100644
> > --- a/include/linux/virtio.h
> > +++ b/include/linux/virtio.h
> > @@ -145,6 +145,12 @@ void virtio_config_changed(struct virtio_device *dev);
> > #ifdef CONFIG_PM_SLEEP
> > int virtio_device_freeze(struct virtio_device *dev);
> > int virtio_device_restore(struct virtio_device *dev);
> > +int virtio_device_suspend(struct virtio_device *dev);
> > +int virtio_device_resume(struct virtio_device *dev);
> > +int virtio_device_suspend_late(struct virtio_device *dev);
> > +int virtio_device_resume_early(struct virtio_device *dev);
> > +int virtio_device_suspend_noirq(struct virtio_device *dev);
> > +int virtio_device_resume_noirq(struct virtio_device *dev);
> > #endif
> > void virtio_reset_device(struct virtio_device *dev);
> >
> > @@ -187,6 +193,12 @@ struct virtio_driver {
> > #ifdef CONFIG_PM
> > int (*freeze)(struct virtio_device *dev);
> > int (*restore)(struct virtio_device *dev);
> > + int (*suspend)(struct virtio_device *dev);
> > + int (*resume)(struct virtio_device *dev);
> > + int (*suspend_late)(struct virtio_device *dev);
> > + int (*resume_early)(struct virtio_device *dev);
> > + int (*suspend_noirq)(struct virtio_device *dev);
> > + int (*resume_noirq)(struct virtio_device *dev);
> > #endif
> > };
> >
> >
> > base-commit: 3f01e9fed8454dcd89727016c3e5b2fbb8f8e50c
> > --
> > 2.17.1
>