Philip Chen wrote: > Hi maintainers, > > Can anyone let me know if this patch makes sense? > Any comment/feedback is appreciated. > Thanks in advance! I'm not an expert on virtio but the code looks ok on the surface. I've discussed this with Dan a bit and virtio-pmem is not heavily tested. Based on our discussion [1] I wonder if there is a way we can recreate this with QEMU to incorporate into our testing? Ira [1] https://lore.kernel.org/lkml/CA+cxXhnb2i5O7_BiOfKLth5Zwp5T62d6F6c39vnuT53cUkU_uw@xxxxxxxxxxxxxx/ > > On Wed, Aug 14, 2024 at 5:46 PM Philip Chen <philipchen@xxxxxxxxxxxx> wrote: > > > > Add basic freeze/restore PM callbacks to support hibernation (S4): > > - On freeze, delete vq and quiesce the device to prepare for > > snapshotting. > > - On restore, re-init vq and mark DRIVER_OK. > > > > Signed-off-by: Philip Chen <philipchen@xxxxxxxxxxxx> > > --- > > drivers/nvdimm/virtio_pmem.c | 24 ++++++++++++++++++++++++ > > 1 file changed, 24 insertions(+) > > > > diff --git a/drivers/nvdimm/virtio_pmem.c b/drivers/nvdimm/virtio_pmem.c > > index c9b97aeabf85..2396d19ce549 100644 > > --- a/drivers/nvdimm/virtio_pmem.c > > +++ b/drivers/nvdimm/virtio_pmem.c > > @@ -143,6 +143,28 @@ static void virtio_pmem_remove(struct virtio_device *vdev) > > virtio_reset_device(vdev); > > } > > > > +static int virtio_pmem_freeze(struct virtio_device *vdev) > > +{ > > + vdev->config->del_vqs(vdev); > > + virtio_reset_device(vdev); > > + > > + return 0; > > +} > > + > > +static int virtio_pmem_restore(struct virtio_device *vdev) > > +{ > > + int ret; > > + > > + ret = init_vq(vdev->priv); > > + if (ret) { > > + dev_err(&vdev->dev, "failed to initialize virtio pmem's vq\n"); > > + return ret; > > + } > > + virtio_device_ready(vdev); > > + > > + return 0; > > +} > > + > > static unsigned int features[] = { > > VIRTIO_PMEM_F_SHMEM_REGION, > > }; > > @@ -155,6 +177,8 @@ static struct virtio_driver virtio_pmem_driver = { > > .validate = virtio_pmem_validate, > > .probe = virtio_pmem_probe, > > .remove = virtio_pmem_remove, > > + .freeze = virtio_pmem_freeze, > > + .restore = virtio_pmem_restore, > > }; > > > > module_virtio_driver(virtio_pmem_driver); > > -- > > 2.46.0.76.ge559c4bf1a-goog > >
