Re: [PATCH v2 3/4] vhost-vdpa: uAPI to stop the device

On Wed, May 25, 2022 at 4:51 AM Jason Wang [off-list ref] wrote:

On Wed, May 25, 2022 at 1:06 AM Eugenio Pérez [off-list ref] wrote:

quoted

The ioctl adds support for stop the device from userspace.

Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
---
 drivers/vhost/vdpa.c       | 18 ++++++++++++++++++
 include/uapi/linux/vhost.h |  3 +++
 2 files changed, 21 insertions(+)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 32713db5831d..a5d33bad92f9 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c

@@ -478,6 +478,21 @@ static long vhost_vdpa_get_vqs_count(struct vhost_vdpa *v, u32 __user *argp)
        return 0;
 }

+static long vhost_vdpa_stop(struct vhost_vdpa *v, u32 __user *argp)
+{
+       struct vdpa_device *vdpa = v->vdpa;
+       const struct vdpa_config_ops *ops = vdpa->config;
+       int stop;
+
+       if (!ops->stop)
+               return -EOPNOTSUPP;
+
+       if (copy_from_user(&stop, argp, sizeof(stop)))
+               return -EFAULT;
+
+       return ops->stop(vdpa, stop);
+}
+
 static long vhost_vdpa_vring_ioctl(struct vhost_vdpa *v, unsigned int cmd,
                                   void __user *argp)
 {

@@ -650,6 +665,9 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep,
        case VHOST_VDPA_GET_VQS_COUNT:
                r = vhost_vdpa_get_vqs_count(v, argp);
                break;
+       case VHOST_STOP:
+               r = vhost_vdpa_stop(v, argp);
+               break;
        default:
                r = vhost_dev_ioctl(&v->vdev, cmd, argp);
                if (r == -ENOIOCTLCMD)

diff --git a/include/uapi/linux/vhost.h b/include/uapi/linux/vhost.h
index cab645d4a645..e7526968ab0c 100644
--- a/include/uapi/linux/vhost.h
+++ b/include/uapi/linux/vhost.h

@@ -171,4 +171,7 @@
 #define VHOST_VDPA_SET_GROUP_ASID      _IOW(VHOST_VIRTIO, 0x7C, \
                                             struct vhost_vring_state)

+/* Stop or resume a device so it does not process virtqueue requests anymore */
+#define VHOST_STOP                     _IOW(VHOST_VIRTIO, 0x7D, int)
+

Unless we know it's a vhost general uAPI, let's use VHOST_VDPA_STOP here.

Ok I'll rename.

Thanks!

Thanks

quoted

 #endif
--
2.27.0