[PATCH 5/5] hisi_acc_vfio_pci: bugfix live migration function without VF device driver

[Longfang Liu <liulongfang@huawei.com>]

If the driver of the VF device is not loaded in the Guest OS,
then perform device data migration. The migrated data address will
be NULL.
The live migration recovery operation on the destination side will
access a null address value, which will cause access errors.

Therefore, live migration of VMs without added VF device drivers
does not require device data migration.
In addition, when the queue address data obtained by the destination
is empty, device queue recovery processing will not be performed.

Signed-off-by: Longfang Liu <liulongfang@huawei.com>
---
 drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
index 8d9e07ebf4fd..9a5f7e9bc695 100644
--- a/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
+++ b/drivers/vfio/pci/hisilicon/hisi_acc_vfio_pci.c
@@ -436,6 +436,7 @@ static int vf_qm_get_match_data(struct hisi_acc_vf_core_device *hisi_acc_vdev,
 				struct acc_vf_data *vf_data)
 {
 	struct hisi_qm *pf_qm = hisi_acc_vdev->pf_qm;
+	struct hisi_qm *vf_qm = &hisi_acc_vdev->vf_qm;
 	struct device *dev = &pf_qm->pdev->dev;
 	int vf_id = hisi_acc_vdev->vf_id;
 	int ret;
@@ -460,6 +461,13 @@ static int vf_qm_get_match_data(struct hisi_acc_vf_core_device *hisi_acc_vdev,
 		return ret;
 	}
 
+	/* Get VF driver insmod state */
+	ret = qm_read_regs(vf_qm, QM_VF_STATE, &vf_data->vf_qm_state, 1);
+	if (ret) {
+		dev_err(dev, "failed to read QM_VF_STATE!\n");
+		return ret;
+	}
+
 	return 0;
 }
 
@@ -499,6 +507,12 @@ static int vf_qm_load_data(struct hisi_acc_vf_core_device *hisi_acc_vdev,
 	qm->qp_base = vf_data->qp_base;
 	qm->qp_num = vf_data->qp_num;
 
+	if (!vf_data->eqe_dma || !vf_data->aeqe_dma ||
+	    !vf_data->sqc_dma || !vf_data->cqc_dma) {
+		dev_err(dev, "resume dma addr is NULL!\n");
+		return -EINVAL;
+	}
+
 	ret = qm_set_regs(qm, vf_data);
 	if (ret) {
 		dev_err(dev, "set VF regs failed\n");
@@ -721,6 +735,9 @@ static int hisi_acc_vf_load_state(struct hisi_acc_vf_core_device *hisi_acc_vdev)
 	struct hisi_acc_vf_migration_file *migf = hisi_acc_vdev->resuming_migf;
 	int ret;
 
+	if (hisi_acc_vdev->vf_qm_state != QM_READY)
+		return 0;
+
 	/* Recover data to VF */
 	ret = vf_qm_load_data(hisi_acc_vdev, migf);
 	if (ret) {
@@ -1524,6 +1541,7 @@ static int hisi_acc_vfio_pci_migrn_init_dev(struct vfio_device *core_vdev)
 	hisi_acc_vdev->vf_id = pci_iov_vf_id(pdev) + 1;
 	hisi_acc_vdev->pf_qm = pf_qm;
 	hisi_acc_vdev->vf_dev = pdev;
+	hisi_acc_vdev->vf_qm_state = QM_NOT_READY;
 	mutex_init(&hisi_acc_vdev->state_mutex);
 	mutex_init(&hisi_acc_vdev->open_mutex);
 
-- 
2.24.0