Minor fix

diff --git a/palacios/src/devices/lnx_virtio_nic.c b/palacios/src/devices/lnx_virtio_nic.c
index f68d3df..0f76641 100644 (file)
--- a/palacios/src/devices/lnx_virtio_nic.c
+++ b/palacios/src/devices/lnx_virtio_nic.c
@@ -280,16 +280,31 @@ static int send_pkt_to_guest(struct virtio_net_state * virtio, uchar_t * buf, ui
        //copy header to the header descriptor
        memcpy((void *)hdr_addr, &hdr, sizeof(struct virtio_net_hdr));
 
+       //Zheng 01/02/2010: zero payload
+       if (offset >= data_len) {
+           hdr_desc->flags &= ~VIRTIO_NEXT_FLAG;
+       }
+
        //copy data to the next descriptors
-       for (buf_idx = 0; offset < data_len; buf_idx = q->desc[hdr_idx].next) {
+       //Zheng 01/02/2010: put data into the next descriptor, rather than 0! 
+       for (buf_idx = hdr_desc->next; offset < data_len; buf_idx = q->desc[hdr_idx].next) {
+       //      for (buf_idx = 0; offset < data_len; buf_idx = q->desc[hdr_idx].next) {
            struct vring_desc * buf_desc = &(q->desc[buf_idx]);
            uint32_t len = 0;
 
-           buf_desc->flags = VIRTIO_NEXT_FLAG;
+           //Zheng 01/02/2010: commented this - we need to check 
+           //       if there still is some data left
+           //buf_desc->flags = VIRTIO_NEXT_FLAG;
         
            len = copy_data_to_desc(virtio, buf_desc, buf + offset, data_len - offset);
            
            offset += len;
+
+           //Zheng 01/02/2010: check if there still is some data left 
+           if (offset < data_len) {
+               buf_desc->flags = VIRTIO_NEXT_FLAG;             
+           }
+
            buf_desc->length = len;  // TODO: do we need this?
        }