[PATCH v2 3/4] vdpa: add get_backend_features vdpa operation
From: Eugenio Pérez <eperezma@redhat.com>
Date: 2023-06-09 09:29:40
Also in:
lkml
Subsystem:
the rest, virtio core, virtio host (vhost) · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
This operation allow vdpa parent to expose its own backend feature bits. Next patches introduce a feature not compatible with all parent drivers: the ability to enable vq after driver_ok. Each parent must declare if it allows it or not. Signed-off-by: Eugenio Pérez <eperezma@redhat.com> Acked-by: Shannon Nelson <redacted> --- drivers/vhost/vdpa.c | 12 ++++++++++++ include/linux/vdpa.h | 4 ++++ 2 files changed, 16 insertions(+)
diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index a3204406b73d..e1abf29fed5b 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c@@ -403,6 +403,17 @@ static long vhost_vdpa_get_features(struct vhost_vdpa *v, u64 __user *featurep) return 0; } +static u64 vhost_vdpa_get_backend_features(const struct vhost_vdpa *v) +{ + struct vdpa_device *vdpa = v->vdpa; + const struct vdpa_config_ops *ops = vdpa->config; + + if (!ops->get_backend_features) + return 0; + else + return ops->get_backend_features(vdpa); +} + static long vhost_vdpa_set_features(struct vhost_vdpa *v, u64 __user *featurep) { struct vdpa_device *vdpa = v->vdpa;
@@ -742,6 +753,7 @@ static long vhost_vdpa_unlocked_ioctl(struct file *filep, features |= BIT_ULL(VHOST_BACKEND_F_SUSPEND); if (vhost_vdpa_can_resume(v)) features |= BIT_ULL(VHOST_BACKEND_F_RESUME); + features |= vhost_vdpa_get_backend_features(v); if (copy_to_user(featurep, &features, sizeof(features))) r = -EFAULT; break;
diff --git a/include/linux/vdpa.h b/include/linux/vdpa.h
index db1b0eaef4eb..0e652026b776 100644
--- a/include/linux/vdpa.h
+++ b/include/linux/vdpa.h@@ -208,6 +208,9 @@ struct vdpa_map_file { * @vdev: vdpa device * Returns the virtio features support by the * device + * @get_backend_features: Get parent-specific backend features (optional) + * Returns the vdpa features supported by the + * device. * @set_driver_features: Set virtio features supported by the driver * @vdev: vdpa device * @features: feature support by the driver
@@ -358,6 +361,7 @@ struct vdpa_config_ops { u32 (*get_vq_align)(struct vdpa_device *vdev); u32 (*get_vq_group)(struct vdpa_device *vdev, u16 idx); u64 (*get_device_features)(struct vdpa_device *vdev); + u64 (*get_backend_features)(const struct vdpa_device *vdev); int (*set_driver_features)(struct vdpa_device *vdev, u64 features); u64 (*get_driver_features)(struct vdpa_device *vdev); void (*set_config_cb)(struct vdpa_device *vdev,
--
2.31.1