[PATCH 3/4] vdpa_sim: support vendor satistics

[Jason Wang <jasowang@redhat.com>]

This patch adds a new config ops callback to allow individual
simulator to implement the vendor stats callback.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 drivers/vdpa/vdpa_sim/vdpa_sim.c | 13 +++++++++++++
 drivers/vdpa/vdpa_sim/vdpa_sim.h |  3 +++
 2 files changed, 16 insertions(+)

diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.c b/drivers/vdpa/vdpa_sim/vdpa_sim.c
index 55aaa023a6e2..02e892f819e7 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.c
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.c
@@ -426,6 +426,18 @@ static int vdpasim_get_vq_state(struct vdpa_device *vdpa, u16 idx,
 	return 0;
 }
 
+static int vdpasim_get_vq_stats(struct vdpa_device *vdpa, u16 idx,
+				struct sk_buff *msg,
+				struct netlink_ext_ack *extack)
+{
+	struct vdpasim *vdpasim = vdpa_to_sim(vdpa);
+
+	if (vdpasim->dev_attr.get_stats)
+		return vdpasim->dev_attr.get_stats(vdpasim, idx,
+						   msg, extack);
+	return -EINVAL;
+}
+
 static u32 vdpasim_get_vq_align(struct vdpa_device *vdpa)
 {
 	return VDPASIM_QUEUE_ALIGN;
@@ -710,6 +722,7 @@ static const struct vdpa_config_ops vdpasim_config_ops = {
 	.set_vq_ready           = vdpasim_set_vq_ready,
 	.get_vq_ready           = vdpasim_get_vq_ready,
 	.set_vq_state           = vdpasim_set_vq_state,
+	.get_vendor_vq_stats    = vdpasim_get_vq_stats,
 	.get_vq_state           = vdpasim_get_vq_state,
 	.get_vq_align           = vdpasim_get_vq_align,
 	.get_vq_group           = vdpasim_get_vq_group,
diff --git a/drivers/vdpa/vdpa_sim/vdpa_sim.h b/drivers/vdpa/vdpa_sim/vdpa_sim.h
index 51c070a543f1..d2a08c0abad7 100644
--- a/drivers/vdpa/vdpa_sim/vdpa_sim.h
+++ b/drivers/vdpa/vdpa_sim/vdpa_sim.h
@@ -48,6 +48,9 @@ struct vdpasim_dev_attr {
 	work_func_t work_fn;
 	void (*get_config)(struct vdpasim *vdpasim, void *config);
 	void (*set_config)(struct vdpasim *vdpasim, const void *config);
+	int (*get_stats)(struct vdpasim *vdpasim, u16 idx,
+			 struct sk_buff *msg,
+			 struct netlink_ext_ack *extack);
 };
 
 /* State of each vdpasim device */
-- 
2.25.1