vdpa/snet: implement the resume vDPA callback

The callback sends a resume command to the DPU through
the control mechanism.

Signed-off-by: Alvaro Karsz <alvaro.karsz@solid-run.com>
Message-Id: <20230502131048.61134-1-alvaro.karsz@solid-run.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Jason Wang <jasowang@redhat.com>

drivers/vdpa/solidrun/snet_ctrl.c

@@ -16,6 +16,7 @@ enum snet_ctrl_opcodes {
 	SNET_CTRL_OP_DESTROY = 1,
 	SNET_CTRL_OP_READ_VQ_STATE,
 	SNET_CTRL_OP_SUSPEND,
+	SNET_CTRL_OP_RESUME,
 };
 
 #define SNET_CTRL_TIMEOUT	        2000000
@@ -328,3 +329,8 @@ int snet_suspend_dev(struct snet *snet)
 {
 	return snet_send_ctrl_msg(snet, SNET_CTRL_OP_SUSPEND, 0);
 }
+
+int snet_resume_dev(struct snet *snet)
+{
+	return snet_send_ctrl_msg(snet, SNET_CTRL_OP_RESUME, 0);
+}

drivers/vdpa/solidrun/snet_main.c

@@ -509,6 +509,20 @@ static int snet_suspend(struct vdpa_device *vdev)
 	return ret;
 }
 
+static int snet_resume(struct vdpa_device *vdev)
+{
+	struct snet *snet = vdpa_to_snet(vdev);
+	int ret;
+
+	ret = snet_resume_dev(snet);
+	if (ret)
+		SNET_ERR(snet->pdev, "SNET[%u] resume failed, err: %d\n", snet->sid, ret);
+	else
+		SNET_DBG(snet->pdev, "Resume SNET[%u] device\n", snet->sid);
+
+	return ret;
+}
+
 static const struct vdpa_config_ops snet_config_ops = {
 	.set_vq_address         = snet_set_vq_address,
 	.set_vq_num             = snet_set_vq_num,
@@ -536,6 +550,7 @@ static const struct vdpa_config_ops snet_config_ops = {
 	.get_config             = snet_get_config,
 	.set_config             = snet_set_config,
 	.suspend		= snet_suspend,
+	.resume			= snet_resume,
 };
 
 static int psnet_open_pf_bar(struct pci_dev *pdev, struct psnet *psnet)

drivers/vdpa/solidrun/snet_vdpa.h

@@ -204,5 +204,6 @@ void snet_ctrl_clear(struct snet *snet);
 int snet_destroy_dev(struct snet *snet);
 int snet_read_vq_state(struct snet *snet, u16 idx, struct vdpa_vq_state *state);
 int snet_suspend_dev(struct snet *snet);
+int snet_resume_dev(struct snet *snet);
 
 #endif //_SNET_VDPA_H_