Add large MTU support into Virtio NIC

[palacios.git] / palacios / src / palacios / vmm_vnet_core.c

diff --git a/palacios/src/palacios/vmm_vnet_core.c b/palacios/src/palacios/vmm_vnet_core.c
index 4b54d71..92f8467 100644 (file)
--- a/palacios/src/palacios/vmm_vnet_core.c
+++ b/palacios/src/palacios/vmm_vnet_core.c
@@ -84,10 +84,11 @@ struct route_list {
 struct queue_entry{
     uint8_t use;
     struct v3_vnet_pkt pkt;
-    uint8_t data[ETHERNET_PACKET_LEN];
+    uint8_t * data;
+    uint32_t size_alloc;
 };
 
-#define VNET_QUEUE_SIZE 10240
+#define VNET_QUEUE_SIZE 1024
 struct vnet_queue {
        struct queue_entry buf[VNET_QUEUE_SIZE];
        int head, tail;
@@ -520,6 +521,7 @@ static int vnet_pkt_enqueue(struct v3_vnet_pkt * pkt){
     unsigned long flags;
     struct queue_entry * entry;
     struct vnet_queue * q = &(vnet_state.pkt_q);
+    uint16_t num_pages;
 
     flags = v3_lock_irqsave(q->lock);
 
@@ -538,6 +540,20 @@ static int vnet_pkt_enqueue(struct v3_vnet_pkt * pkt){
     /* this is ugly, but should happen very unlikely */
     while(entry->use);
 
+    if(entry->size_alloc < pkt->size){
+       if(entry->data != NULL){
+           V3_FreePages(V3_PAddr(entry->data), (entry->size_alloc / PAGE_SIZE));
+           entry->data = NULL;
+       }
+
+       num_pages = 1 + (pkt->size / PAGE_SIZE);
+       entry->data = V3_VAddr(V3_AllocPages(num_pages));
+       if(entry->data == NULL){
+           return -1;
+       }
+       entry->size_alloc = PAGE_SIZE * num_pages;
+    }
+
     entry->pkt.data = entry->data;
     memcpy(&(entry->pkt), pkt, sizeof(struct v3_vnet_pkt));
     memcpy(entry->data, pkt->data, pkt->size);
@@ -719,6 +735,8 @@ static int vnet_tx_flush(void *args){
            /* this is ugly, but should happen very unlikely */
            while(!entry->use);
            vnet_tx_one_pkt(&(entry->pkt), NULL);
+
+           /* asynchronizely release allocated memory for buffer entry here */     
            entry->use = 0;
 
            V3_Net_Print(2, "vnet_tx_flush: pkt (size %d)\n", entry->pkt.size);