[PATCH v3 6/7] vduse: Update the vq_info in ioctl VDUSE_VQ_GET_INFO

[Cindy Lu <lulu@redhat.com>]

Once the reconnect memory pages are mapped to userspace, the userspace
application will update the "reconnected" bit in the
"struct vduse_dev_reconnect_data".
The kernel will then check this bit. If it is not set to
"VDUSE_NOT_RECONNECT", it means that the application has been
reconnected, and the kernel will synchronize the vq information.

Signed-off-by: Cindy Lu <lulu@redhat.com>
---
 drivers/vdpa/vdpa_user/vduse_dev.c | 24 +++++++++++++++++++++++-
 1 file changed, 23 insertions(+), 1 deletion(-)

diff --git a/drivers/vdpa/vdpa_user/vduse_dev.c b/drivers/vdpa/vdpa_user/vduse_dev.c
index f55f415629de..422f1aedebac 100644
--- a/drivers/vdpa/vdpa_user/vduse_dev.c
+++ b/drivers/vdpa/vdpa_user/vduse_dev.c
@@ -1193,6 +1193,9 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
 		struct vduse_vq_info vq_info;
 		struct vduse_virtqueue *vq;
 		u32 index;
+		unsigned long vaddr;
+		struct vduse_vq_state *vq_reconnect;
+		struct vduse_dev_reconnect_data *dev_reconnect;
 
 		ret = -EFAULT;
 		if (copy_from_user(&vq_info, argp, sizeof(vq_info)))
@@ -1209,6 +1212,12 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
 		vq_info.device_addr = vq->device_addr;
 		vq_info.num = vq->num;
 
+		vaddr = dev->vdpa_reconnect_vaddr;
+		dev_reconnect = (struct vduse_dev_reconnect_data *)vaddr;
+
+		vaddr = vq->vdpa_reconnect_vaddr;
+		vq_reconnect = (struct vduse_vq_state *)vaddr;
+
 		if (dev->driver_features & BIT_ULL(VIRTIO_F_RING_PACKED)) {
 			vq_info.packed.last_avail_counter =
 				vq->state.packed.last_avail_counter;
@@ -1218,9 +1227,22 @@ static long vduse_dev_ioctl(struct file *file, unsigned int cmd,
 				vq->state.packed.last_used_counter;
 			vq_info.packed.last_used_idx =
 				vq->state.packed.last_used_idx;
-		} else
+			/*check if the vq is reconnect, if yes then update the info*/
+			if (dev_reconnect->reconnected != VDUSE_NOT_RECONNECT) {
+				vq_info.packed.last_avail_idx =
+					vq_reconnect->packed.last_avail_idx;
+				vq_info.packed.last_avail_counter =
+					vq_reconnect->packed.last_avail_counter;
+			}
+		} else {
 			vq_info.split.avail_index =
 				vq->state.split.avail_index;
+			/*check if the vq is reconnect, if yes then update the info*/
+			if (dev_reconnect->reconnected != VDUSE_NOT_RECONNECT) {
+				vq_info.split.avail_index =
+					vq_reconnect->split.avail_index;
+			}
+		}
 
 		vq_info.ready = vq->ready;
 
-- 
2.34.3