Palacios Public Git Repository

To checkout Palacios execute

  git clone http://v3vee.org/palacios/palacios.web/palacios.git
This will give you the master branch. You probably want the devel branch or one of the release branches. To switch to the devel branch, simply execute
  cd palacios
  git checkout --track -b devel origin/devel
The other branches are similar.


format fixes
[palacios.git] / palacios / src / palacios / vmm_vnet.c
index d2602c5..d7455ac 100644 (file)
@@ -47,7 +47,7 @@ struct vnet_dev {
     uint8_t mac_addr[6];
     struct v3_vm_info * vm;
     
-    int (*input)(struct v3_vm_info * vm, struct v3_vnet_pkt * pkt,  void * private_data);
+    int (*input)(struct v3_vm_info * vm, struct v3_vnet_pkt * pkt, void * private_data);
     void * private_data;
     
     int dev_id;
@@ -55,6 +55,30 @@ struct vnet_dev {
 } __attribute__((packed));
 
 
+#define BRIDGE_BUF_SIZE 512
+struct bridge_pkts_buf {
+    int start, end;
+    int num; 
+    v3_lock_t lock;
+    struct v3_vnet_pkt pkts[BRIDGE_BUF_SIZE];
+    uint8_t datas[ETHERNET_PACKET_LEN * BRIDGE_BUF_SIZE];
+};
+
+struct vnet_brg_dev {
+    struct v3_vm_info * vm;
+    
+    int (*input)(struct v3_vm_info * vm, struct v3_vnet_pkt pkt[], uint16_t pkt_num, void * private_data);
+    void (*xcall_input)(void * data);
+    int (*polling_pkt)(struct v3_vm_info * vm,  void * private_data);
+
+    int disabled;
+       
+    uint16_t max_delayed_pkts;
+    long max_latency; //in cycles
+    void * private_data;
+} __attribute__((packed));
+
+
 
 
 
@@ -69,8 +93,6 @@ struct vnet_route_info {
 };
 
 
-
-
 struct route_list {
     uint8_t hash_buf[VNET_HASH_SIZE];
 
@@ -83,27 +105,73 @@ struct route_list {
 static struct {
     struct list_head routes;
     struct list_head devs;
-
+    
     int num_routes;
     int num_devs;
 
+    struct vnet_brg_dev * bridge;
+
     v3_lock_t lock;
 
-    struct gen_queue * inpkt_q;
     struct hashtable * route_cache;
 
+    struct bridge_pkts_buf in_buf;  //incoming packets buffer
 } vnet_state;
 
 
 
 
 #ifdef CONFIG_DEBUG_VNET
-static inline void mac_to_string(char mac[6], char * buf) {
-    snprintf(buf, 20, "%02x:%02x:%02x:%02x:%02x:%02x", 
+static inline void mac_to_string(uint8_t mac[6], char * buf) {
+    snprintf(buf, 100, "%d:%d:%d:%d:%d:%d", 
             mac[0], mac[1], mac[2],
             mac[3], mac[4], mac[5]);
 }
 
+static void print_route(struct vnet_route_info * route){
+    char str[50];
+
+    memset(str, 0, 50);
+
+    mac_to_string(route->route_def.src_mac, str);
+    PrintDebug("Src Mac (%s),  src_qual (%d)\n", 
+                       str, route->route_def.src_mac_qual);
+
+    mac_to_string(route->route_def.dst_mac, str);
+    PrintDebug("Dst Mac (%s),  dst_qual (%d)\n", 
+                       str, route->route_def.dst_mac_qual);
+
+    PrintDebug("Src dev id (%d), src type (%d)", 
+                       route->route_def.src_id, 
+                       route->route_def.src_type);
+
+    PrintDebug("Dst dev id (%d), dst type (%d)\n", 
+                       route->route_def.dst_id, 
+                       route->route_def.dst_type);
+
+    if (route->route_def.dst_type == LINK_INTERFACE) {
+       PrintDebug("dst_dev (%p), dst_dev_id (%d), dst_dev_input (%p), dst_dev_data (%p)\n",
+                  route->dst_dev,
+                  route->dst_dev->dev_id,
+                  route->dst_dev->input,
+                  route->dst_dev->private_data);
+    }
+}
+
+static void dump_routes() {
+       struct vnet_route_info * route = NULL;
+       int i = 0;
+
+       PrintDebug("\n========Dump routes starts ============\n");
+
+       list_for_each_entry(route, &(vnet_state.routes), node) {
+               PrintDebug("\nroute %d:\n", i++);
+               print_route(route);
+       }
+
+       PrintDebug("\n========Dump routes end ============\n");
+}
+
 #endif
 
 
@@ -112,17 +180,16 @@ static inline void mac_to_string(char mac[6], char * buf) {
  * This means we can generate the hash from an offset into the pkt struct
  */
 static inline uint_t hash_fn(addr_t hdr_ptr) {    
-    uint8_t * hdr_buf = (uint8_t *)&(hdr_ptr);
-    
+    uint8_t * hdr_buf = (uint8_t *)hdr_ptr;
+
     return v3_hash_buffer(hdr_buf, VNET_HASH_SIZE);
 }
 
-static inline int hash_eq(addr_t key1, addr_t key2) {
+static inline int hash_eq(addr_t key1, addr_t key2) {  
     return (memcmp((uint8_t *)key1, (uint8_t *)key2, VNET_HASH_SIZE) == 0);
 }
 
-
-static int add_route_to_cache(struct v3_vnet_pkt * pkt, struct route_list * routes) {
+static int add_route_to_cache(const struct v3_vnet_pkt * pkt, struct route_list * routes) {
     memcpy(routes->hash_buf, pkt->hash_buf, VNET_HASH_SIZE);    
 
     if (v3_htable_insert(vnet_state.route_cache, (addr_t)routes->hash_buf, (addr_t)routes) == 0) {
@@ -141,53 +208,74 @@ static int clear_hash_cache() {
     return 0;
 }
 
-static int look_into_cache(struct v3_vnet_pkt * pkt, struct route_list ** routes) {
+static int look_into_cache(const struct v3_vnet_pkt * pkt, struct route_list ** routes) {
     
-    *routes = (struct route_list *)v3_htable_search(vnet_state.route_cache, (addr_t)pkt);
+    *routes = (struct route_list *)v3_htable_search(vnet_state.route_cache, (addr_t)(pkt->hash_buf));
    
     return 0;
 }
 
 
-struct vnet_dev * find_dev_by_id(int idx) {
+static struct vnet_dev * find_dev_by_id(int idx) {
     struct vnet_dev * dev = NULL; 
     
     list_for_each_entry(dev, &(vnet_state.devs), node) {
        int dev_id = dev->dev_id;
 
-       if (dev_id == idx)
+       if (dev_id == idx) {
            return dev;
+       }
     }
 
     return NULL;
 }
 
-static struct vnet_dev * find_dev_by_mac(char * name) {
+static struct vnet_dev * find_dev_by_mac(char mac[6]) {
     struct vnet_dev * dev = NULL; 
     
     list_for_each_entry(dev, &(vnet_state.devs), node) {
-       if (!memcmp(dev->mac_addr, name, 6))
+       if (memcmp(dev->mac_addr, mac, 6) == 0) {
            return dev;
+       }
     }
 
     return NULL;
 }
 
+int get_device_id_by_mac(char mac[6]) {
+    struct vnet_dev * dev = find_dev_by_mac(mac);
+    
+    if (dev == NULL) {
+       return -1;
+    }
+    
+    return dev->dev_id;
+}
+
 
 int v3_vnet_add_route(struct v3_vnet_route route) {
     struct vnet_route_info * new_route = NULL;
-    unsigned long flags; 
+    uint32_t flags = 0; 
 
     new_route = (struct vnet_route_info *)V3_Malloc(sizeof(struct vnet_route_info));
     memset(new_route, 0, sizeof(struct vnet_route_info));
 
-    PrintDebug("Vnet: vnet_add_route_entry\n");        
+    PrintDebug("Vnet: vnet_add_route_entry: dst_id: %d, dst_type: %d\n",
+                       route.dst_id, route.dst_type);  
     
-    new_route->route_def = route;
+    memcpy(new_route->route_def.src_mac, route.src_mac, 6);
+    memcpy(new_route->route_def.dst_mac, route.dst_mac, 6);
+    new_route->route_def.src_mac_qual = route.src_mac_qual;
+    new_route->route_def.dst_mac_qual = route.dst_mac_qual;
+    new_route->route_def.dst_id = route.dst_id;
+    new_route->route_def.dst_type = route.dst_type;
+    new_route->route_def.src_id = route.src_id;
+    new_route->route_def.src_type = route.src_type;
 
-    /* TODO: Find devices */
     if (new_route->route_def.dst_type == LINK_INTERFACE) {
        new_route->dst_dev = find_dev_by_id(new_route->route_def.dst_id);
+       PrintDebug("Vnet: Add route, get device: dev_id %d, input : %p, private_data %p\n",
+                       new_route->dst_dev->dev_id, new_route->dst_dev->input, new_route->dst_dev->private_data);
     }
 
     if (new_route->route_def.src_type == LINK_INTERFACE) {
@@ -195,10 +283,16 @@ int v3_vnet_add_route(struct v3_vnet_route route) {
     }
 
     flags = v3_lock_irqsave(vnet_state.lock);
+
     list_add(&(new_route->node), &(vnet_state.routes));
+    clear_hash_cache();
+
     v3_unlock_irqrestore(vnet_state.lock, flags);
    
-    clear_hash_cache();
+
+#ifdef CONFIG_DEBUG_VNET
+    dump_routes();
+#endif
 
     return 0;
 }
@@ -207,7 +301,7 @@ int v3_vnet_add_route(struct v3_vnet_route route) {
 
 // At the end allocate a route_list
 // This list will be inserted into the cache so we don't need to free it
-static struct route_list * match_route(struct v3_vnet_pkt * pkt) {
+static struct route_list * match_route(const struct v3_vnet_pkt * pkt) {
     struct vnet_route_info * route = NULL; 
     struct route_list * matches = NULL;
     int num_matches = 0;
@@ -219,8 +313,8 @@ static struct route_list * match_route(struct v3_vnet_pkt * pkt) {
 
 #ifdef CONFIG_DEBUG_VNET
     {
-       char dst_str[18];
-       char src_str[18];
+       char dst_str[100];
+       char src_str[100];
 
        mac_to_string(hdr->src_mac, src_str);  
        mac_to_string(hdr->dst_mac, dst_str);
@@ -304,7 +398,7 @@ static struct route_list * match_route(struct v3_vnet_pkt * pkt) {
        }
        
        // Default route
-       if ( (memcmp(route_def->src_mac, hdr->src_mac, 6) == 0) &
+       if ( (memcmp(route_def->src_mac, hdr->src_mac, 6) == 0) &&
             (route_def->dst_mac_qual == MAC_NONE)) {
            UPDATE_MATCHES(4);
        }
@@ -316,14 +410,14 @@ static struct route_list * match_route(struct v3_vnet_pkt * pkt) {
        return NULL;
     }
 
-    matches = V3_Malloc(sizeof(struct route_list) + 
-                       (sizeof(struct vnet_route_info *) * num_matches));
+    matches = (struct route_list *)V3_Malloc(sizeof(struct route_list) + 
+                               (sizeof(struct vnet_route_info *) * num_matches));
 
     matches->num_routes = num_matches;
 
     {
        int i = 0;
-       list_for_each_entry(route, &match_list, node) {
+       list_for_each_entry(route, &match_list, match_node) {
            matches->routes[i++] = route;
        }
     }
@@ -331,21 +425,118 @@ static struct route_list * match_route(struct v3_vnet_pkt * pkt) {
     return matches;
 }
 
-static int handle_one_pkt(struct v3_vnet_pkt * pkt) {
-    struct route_list * matched_routes = NULL;
-    unsigned long flags;
-    int i;
+#if 0
+static int flush_bridge_pkts(struct vnet_brg_dev *bridge){
+    uint32_t flags;
+    int num;
+    int start;
+    int send;
+    struct v3_vnet_bridge_input_args args;
+    int cpu_id = bridge->vm->cores[0].cpu_id;
+    int current_core = V3_Get_CPU();
+       
+    if (bridge == NULL) {
+       PrintDebug("VNET: No bridge to sent data to links\n");
+       return -1;
+    }
 
+    flags = v3_lock_irqsave(bridge->recv_buf.lock);
+               
+    num = bridge->recv_buf.num;
+    start = bridge->recv_buf.start;
 
-#ifdef CONFIG_DEBUG_VNET
-   {
-       struct eth_hdr * hdr = (struct eth_hdr *)(pkt->data);
-       char dest_str[18];
-       char src_str[18];
+    bridge->recv_buf.num -= num;
+    bridge->recv_buf.start += num;
+    bridge->recv_buf.start %= BRIDGE_BUF_SIZE;
+       
+    v3_unlock_irqrestore(bridge->recv_buf.lock, flags);
+
+
+    if (bridge->disabled) {
+       PrintDebug("VNET: In flush bridge pkts: Bridge is disabled\n");
+       return -1;
+    }
+
+    if (num <= 2 && num > 0) {
+       PrintDebug("VNET: In flush bridge pkts: %d\n", num);
+    }
 
+    if (num > 0) {
+       PrintDebug("VNET: In flush bridge pkts to bridge, cur_cpu %d, brige_core: %d\n", current_core, cpu_id);
+       if (current_core == cpu_id) {
+           if ((start + num) < BRIDGE_BUF_SIZE) { 
+               bridge->input(bridge->vm, &(bridge->recv_buf.pkts[start]), num, bridge->private_data);
+           } else {
+               bridge->input(bridge->vm, &(bridge->recv_buf.pkts[start]), (BRIDGE_BUF_SIZE - start), bridge->private_data);                            
+               send = num - (BRIDGE_BUF_SIZE - start);
+               bridge->input(bridge->vm, &(bridge->recv_buf.pkts[0]), send, bridge->private_data);
+           }   
+       } else {
+           args.vm = bridge->vm;
+           args.private_data = bridge->private_data;
+       
+           if ((start + num) < BRIDGE_BUF_SIZE) {
+               args.pkt_num = num;
+               args.vnet_pkts = &(bridge->recv_buf.pkts[start]);
+               V3_Call_On_CPU(cpu_id, bridge->xcall_input, (void *)&args);
+           } else {
+               args.pkt_num = BRIDGE_BUF_SIZE - start;
+               args.vnet_pkts = &(bridge->recv_buf.pkts[start]);
+               V3_Call_On_CPU(cpu_id, bridge->xcall_input, (void *)&args);
+                               
+               send = num - (BRIDGE_BUF_SIZE - start);
+               args.pkt_num = send;
+               args.vnet_pkts = &(bridge->recv_buf.pkts[0]);                   
+               V3_Call_On_CPU(cpu_id, bridge->xcall_input, (void *)&args);
+           }
+       }
+       
+       PrintDebug("VNET: flush bridge pkts %d\n", num);
+    }
+                       
+    return 0;
+}
+#endif
+
+static int send_to_bridge(struct v3_vnet_pkt * pkt){
+    struct vnet_brg_dev * bridge = vnet_state.bridge;
+
+    if (bridge == NULL) {
+       PrintDebug("VNET: No bridge to sent data to links\n");
+       return -1;
+    }
+
+    if (bridge->max_delayed_pkts <= 1) {
+
+       if (bridge->disabled) {
+           PrintDebug("VNET: Bridge diabled\n");
+           return -1;
+       }
+
+       bridge->input(bridge->vm, pkt, 1, bridge->private_data);
+
+       PrintDebug("VNET: sent one packet to the bridge\n");
+    }
+
+
+    return 0;
+}
+
+int v3_vnet_send_pkt(struct v3_vnet_pkt * pkt, void * private_data) {
+    struct route_list * matched_routes = NULL;
+    uint32_t flags = 0;
+    int i = 0;
+    
+#ifdef CONFIG_DEBUG_VNET
+    {
+       struct eth_hdr * hdr = (struct eth_hdr *)(pkt->header);
+       char dest_str[100];
+       char src_str[100];
+       int cpu = V3_Get_CPU();
+       
        mac_to_string(hdr->src_mac, src_str);  
        mac_to_string(hdr->dst_mac, dest_str);
-       PrintDebug("Vnet: HandleDataOverLink. SRC(%s), DEST(%s)\n", src_str, dest_str);
+       PrintDebug("Vnet: on cpu %d, HandleDataOverLink. SRC(%s), DEST(%s), pkt size: %d\n", cpu, src_str, dest_str, pkt->size);
    }
 #endif
 
@@ -354,25 +545,35 @@ static int handle_one_pkt(struct v3_vnet_pkt * pkt) {
     look_into_cache(pkt, &matched_routes);
        
     if (matched_routes == NULL) {  
-        matched_routes = match_route(pkt);
-               
-      if (matched_routes) {
+       PrintDebug("Vnet: send pkt Looking into routing table\n");
+       
+       matched_routes = match_route(pkt);
+       
+       if (matched_routes) {
            add_route_to_cache(pkt, matched_routes);
        } else {
-           PrintError("Could not find route for packet...\n");
+           PrintDebug("Could not find route for packet... discards packet\n");
            v3_unlock_irqrestore(vnet_state.lock, flags);
            return -1;
        }
     }
 
     v3_unlock_irqrestore(vnet_state.lock, flags);
-    
-    
-    for (i = 0; i < matched_routes->num_routes; i++) {
-       struct vnet_route_info * route = matched_routes->routes[i];
 
-        if (route->route_def.dst_type == LINK_EDGE) {
+    PrintDebug("Vnet: send pkt route matches %d\n", matched_routes->num_routes);
 
+    for (i = 0; i < matched_routes->num_routes; i++) {
+        struct vnet_route_info * route = matched_routes->routes[i];
+       
+        if (route->route_def.dst_type == LINK_EDGE) {                  
+            pkt->dst_type = LINK_EDGE;
+            pkt->dst_id = route->route_def.dst_id;
+
+            if (send_to_bridge(pkt) == -1) {
+                PrintDebug("VNET: Packet not sent properly to bridge\n");
+                continue;
+            }
+            
         } else if (route->route_def.dst_type == LINK_INTERFACE) {
             if (route->dst_dev->input(route->dst_dev->vm, pkt, route->dst_dev->private_data) == -1) {
                 PrintDebug("VNET: Packet not sent properly\n");
@@ -383,39 +584,89 @@ static int handle_one_pkt(struct v3_vnet_pkt * pkt) {
             continue;
         }
 
-        PrintDebug("Vnet: HandleDataOverLink: Forward packet according to Route\n");
+        PrintDebug("Vnet: v3_vnet_send_pkt: Forward packet according to Route %d\n", i);
     }
     
     return 0;
 }
 
-int v3_vnet_send_pkt(struct v3_vnet_pkt * pkt) {
-    
-    PrintDebug("In Vnet Send: pkt size: %d\n", pkt->size);
+void v3_vnet_send_pkt_xcall(void * data) {
+    struct v3_vnet_pkt * pkt = (struct v3_vnet_pkt *)data;
+    v3_vnet_send_pkt(pkt, NULL);
+}
+
+
+void v3_vnet_polling() {
+    uint32_t flags = 0;
+    int num = 0;
+    int start = 0;
+    struct v3_vnet_pkt * buf = NULL;
+
+    PrintDebug("In vnet pollling: cpu %d\n", V3_Get_CPU());
+
+    flags = v3_lock_irqsave(vnet_state.in_buf.lock);
                
-    if (handle_one_pkt(pkt) != -1) {
-        PrintDebug("VNET: send one packet! pt length %d\n", pkt->size);  
-    } else {
-        PrintDebug("VNET: Fail to forward one packet, discard it!\n"); 
+    num = vnet_state.in_buf.num;
+    start = vnet_state.in_buf.start;
+
+    PrintDebug("VNET: polling pkts %d\n", num);
+
+    while (num > 0) {
+       buf = &(vnet_state.in_buf.pkts[vnet_state.in_buf.start]);
+
+       v3_vnet_send_pkt(buf, NULL);
+
+       vnet_state.in_buf.num--;
+       vnet_state.in_buf.start++;
+       vnet_state.in_buf.start %= BRIDGE_BUF_SIZE;
+       num--;
     }
 
+    v3_unlock_irqrestore(vnet_state.in_buf.lock, flags);
+
+    return;
+}
+
+
+int v3_vnet_rx(uint8_t * buf, uint16_t size, uint16_t src_id, uint8_t src_type) {
+    uint32_t flags = 0;
+    int end = 0;
+    struct v3_vnet_pkt * pkt = NULL;
+   
+    flags = v3_lock_irqsave(vnet_state.in_buf.lock);
+           
+    end = vnet_state.in_buf.end;
+    pkt = &(vnet_state.in_buf.pkts[end]);
+
+    if (vnet_state.in_buf.num > BRIDGE_BUF_SIZE){
+       PrintDebug("VNET: bridge rx: buffer full\n");
+       v3_unlock_irqrestore(vnet_state.in_buf.lock, flags);
+       return 0;
+    }
+
+    vnet_state.in_buf.num++;
+    vnet_state.in_buf.end++;
+    vnet_state.in_buf.end %= BRIDGE_BUF_SIZE;
+
+    pkt->size = size;
+    pkt->src_id = src_id;
+    pkt->src_type = src_type;
+    memcpy(pkt->header, buf, ETHERNET_HEADER_LEN);
+    memcpy(pkt->data, buf, size);
+
+       
+    v3_unlock_irqrestore(vnet_state.in_buf.lock, flags);
+
     return 0;
 }
+       
 
-int v3_vnet_add_dev(struct v3_vm_info *vm,uint8_t mac[6], 
+int v3_vnet_add_dev(struct v3_vm_info * vm, uint8_t mac[6], 
                    int (*netif_input)(struct v3_vm_info * vm, struct v3_vnet_pkt * pkt, void * private_data), 
                    void * priv_data){
     struct vnet_dev * new_dev = NULL;
+    uint32_t flags = 0;
 
-    new_dev = find_dev_by_mac(mac);
-
-    PrintDebug("VNET: register device\n");
-
-    if (new_dev) {
-       PrintDebug("VNET: register device: Already has device with the same mac\n");
-       return -1;
-    }
-    
     new_dev = (struct vnet_dev *)V3_Malloc(sizeof(struct vnet_dev)); 
 
     if (new_dev == NULL) {
@@ -427,35 +678,154 @@ int v3_vnet_add_dev(struct v3_vm_info *vm,uint8_t mac[6],
     new_dev->input = netif_input;
     new_dev->private_data = priv_data;
     new_dev->vm = vm;
+    new_dev->dev_id = 0;       
+
+    flags = v3_lock_irqsave(vnet_state.lock);
+
+    if (!find_dev_by_mac(mac)) {
+       list_add(&(new_dev->node), &(vnet_state.devs));
+       new_dev->dev_id = ++vnet_state.num_devs;
+    }
+
+    v3_unlock_irqrestore(vnet_state.lock, flags);
+
+    // if the device was found previosly the id should still be 0
+    if (new_dev->dev_id == 0) {
+       PrintError("Device Alrady exists\n");
+       return -1;
+    }
+
+    PrintDebug("Vnet: Add Device: dev_id %d, input : %p, private_data %p\n",
+              new_dev->dev_id, new_dev->input, new_dev->private_data);
+
+    return new_dev->dev_id;
+}
+
+
+void v3_vnet_heartbeat(struct guest_info *core){
+    //static long last_time, cur_time;
+
+    if (vnet_state.bridge == NULL) {
+       return;
+    }
+/*     
+    if(vnet_state.bridge->max_delayed_pkts > 1){
+       if(V3_Get_CPU() != vnet_state.bridge->vm->cores[0].cpu_id){
+           rdtscll(cur_time);
+       }
+
+       if ((cur_time - last_time) >= vnet_state.bridge->max_latency) {
+           last_time = cur_time;
+           flush_bridge_pkts(vnet_state.bridge);
+       }
+    }
+*/
+    vnet_state.bridge->polling_pkt(vnet_state.bridge->vm, vnet_state.bridge->private_data);
+}
 
-    PrintDebug("VNET: register device new_dev22 %p\n", (void *)new_dev);
+int v3_vnet_add_bridge(struct v3_vm_info * vm,
+                      int (*input)(struct v3_vm_info * vm, struct v3_vnet_pkt pkt[], uint16_t pkt_num, void * private_data),
+                      void (*xcall_input)(void * data),
+                      int (*poll_pkt)(struct v3_vm_info * vm, void * private_data),
+                      uint16_t max_delayed_pkts,
+                      long max_latency,
+                      void * priv_data) {
+
+    uint32_t flags = 0;
+    int bridge_free = 0;
+    struct vnet_brg_dev * tmp_bridge = NULL;    
+    
+    flags = v3_lock_irqsave(vnet_state.lock);
+
+    if (vnet_state.bridge == NULL) {
+       bridge_free = 1;
+       vnet_state.bridge = (void *)1;
+    }
+
+    v3_unlock_irqrestore(vnet_state.lock, flags);
+
+    if (bridge_free == 0) {
+       PrintError("Bridge already set\n");
+       return -1;
+    }
+
+    tmp_bridge = (struct vnet_brg_dev *)V3_Malloc(sizeof(struct vnet_brg_dev));
+
+    if (tmp_bridge == NULL) {
+       PrintError("Malloc Fails\n");
+       vnet_state.bridge = NULL;
+       return -1;
+    }
+    
+    tmp_bridge->vm = vm;
+    tmp_bridge->input = input;
+    tmp_bridge->xcall_input = xcall_input;
+    tmp_bridge->polling_pkt = poll_pkt;
+    tmp_bridge->private_data = priv_data;
+    tmp_bridge->disabled = 0;
+
+/*
+    //initial receving buffer
+    tmp_bridge->recv_buf.start = 0;
+    tmp_bridge->recv_buf.end = 0;
+    tmp_bridge->recv_buf.num = 0;
+    if(v3_lock_init(&(tmp_bridge->recv_buf.lock)) == -1){
+       PrintError("VNET: add bridge, error to initiate recv buf lock\n");
+    }
+    int i;
+    for(i = 0; i<BRIDGE_BUF_SIZE; i++){
+       tmp_bridge->recv_buf.pkts[i].data = &(tmp_bridge->recv_buf.datas[i*ETHERNET_PACKET_LEN]);
+    }
+
+*/
+    
+    tmp_bridge->max_delayed_pkts = (max_delayed_pkts < BRIDGE_BUF_SIZE) ? max_delayed_pkts : BRIDGE_BUF_SIZE;
+    tmp_bridge->max_latency = max_latency;
        
-    list_add(&(new_dev->node), &(vnet_state.devs));
-    vnet_state.num_devs ++;
-    new_dev->dev_id = vnet_state.num_devs;
+    // make this atomic to avoid possible race conditions
+    flags = v3_lock_irqsave(vnet_state.lock);
+    vnet_state.bridge = tmp_bridge;
+    v3_unlock_irqrestore(vnet_state.lock, flags);
 
     return 0;
 }
 
-#if 0
-static int v3_vnet_pkt_process() {
-    struct v3_vnet_pkt * pkt = NULL;
 
-    while ((pkt = (struct v3_vnet_pkt *)v3_dequeue(vnet_state.inpkt_q)) != NULL) {
-        if (handle_one_pkt(pkt) != -1) {
-            PrintDebug("VNET: vnet_check: handle one packet! pt length %d\n", (int)pkt->size);  
-        } else {
-            PrintDebug("VNET: vnet_check: Fail to forward one packet, discard it!\n"); 
-        }
-       
-        V3_Free(pkt); // be careful here
+int v3_vnet_disable_bridge() {
+    uint32_t flags = 0; 
+    
+    flags = v3_lock_irqsave(vnet_state.lock);
+
+    if (vnet_state.bridge != NULL) {
+       vnet_state.bridge->disabled = 1;
     }
+
+    v3_unlock_irqrestore(vnet_state.lock, flags);
+
+    return 0;
+}
+
+
+int v3_vnet_enable_bridge() {
+    uint32_t flags = 0;
     
+    flags = v3_lock_irqsave(vnet_state.lock);
+
+    if (vnet_state.bridge != NULL) {
+       vnet_state.bridge->disabled = 0;
+    }
+
+    v3_unlock_irqrestore(vnet_state.lock, flags);
+
     return 0;
 }
-#endif
+
+
 
 int V3_init_vnet() {
+    int i = 0;
+
+    memset(&vnet_state, 0, sizeof(vnet_state));
        
     INIT_LIST_HEAD(&(vnet_state.routes));
     INIT_LIST_HEAD(&(vnet_state.devs));
@@ -470,11 +840,21 @@ int V3_init_vnet() {
     }
 
     PrintDebug("VNET: Locks initiated\n");
+    
+    //initial incoming pkt buffer
+    vnet_state.in_buf.start = 0;
+    vnet_state.in_buf.end = 0;
+    vnet_state.in_buf.num = 0;
+
+    if (v3_lock_init(&(vnet_state.in_buf.lock)) == -1){
+       PrintError("VNET: add bridge, error to initiate send buf lock\n");
+    }
+
+    for (i = 0; i < BRIDGE_BUF_SIZE; i++){
+       vnet_state.in_buf.pkts[i].data = &(vnet_state.in_buf.datas[i * ETHERNET_PACKET_LEN]);
+    }
 
-    /*initial pkt receiving queue */
-    vnet_state.inpkt_q = v3_create_queue();
-    v3_init_queue(vnet_state.inpkt_q);
-    PrintDebug("VNET: Receiving queue initiated\n");
+    PrintDebug("VNET: Receiving buffer initiated\n");
 
     vnet_state.route_cache = v3_create_htable(0, &hash_fn, &hash_eq);