Staging: batman-adv: Unify sysfs file names with their bat_priv atomics
[firefly-linux-kernel-4.4.55.git] / drivers / staging / batman-adv / unicast.c
index 27c4abb25302729ad0c96ec703db78d470cb60a4..5ae959327b489dd597143b9985f14728b3ed061d 100644 (file)
 #include "routing.h"
 #include "hard-interface.h"
 
+
+static struct sk_buff *frag_merge_packet(struct list_head *head,
+                                        struct frag_packet_list_entry *tfp,
+                                        struct sk_buff *skb)
+{
+       struct unicast_frag_packet *up =
+               (struct unicast_frag_packet *)skb->data;
+       struct sk_buff *tmp_skb;
+       struct unicast_packet *unicast_packet;
+       int hdr_len = sizeof(struct unicast_packet),
+           uni_diff = sizeof(struct unicast_frag_packet) - hdr_len;
+
+       /* set skb to the first part and tmp_skb to the second part */
+       if (up->flags & UNI_FRAG_HEAD) {
+               tmp_skb = tfp->skb;
+       } else {
+               tmp_skb = skb;
+               skb = tfp->skb;
+       }
+
+       skb_pull(tmp_skb, sizeof(struct unicast_frag_packet));
+       if (pskb_expand_head(skb, 0, tmp_skb->len, GFP_ATOMIC) < 0) {
+               /* free buffered skb, skb will be freed later */
+               kfree_skb(tfp->skb);
+               return NULL;
+       }
+
+       /* move free entry to end */
+       tfp->skb = NULL;
+       tfp->seqno = 0;
+       list_move_tail(&tfp->list, head);
+
+       memcpy(skb_put(skb, tmp_skb->len), tmp_skb->data, tmp_skb->len);
+       kfree_skb(tmp_skb);
+
+       memmove(skb->data + uni_diff, skb->data, hdr_len);
+       unicast_packet = (struct unicast_packet *) skb_pull(skb, uni_diff);
+       unicast_packet->packet_type = BAT_UNICAST;
+
+       return skb;
+}
+
+static void frag_create_entry(struct list_head *head, struct sk_buff *skb)
+{
+       struct frag_packet_list_entry *tfp;
+       struct unicast_frag_packet *up =
+               (struct unicast_frag_packet *)skb->data;
+
+       /* free and oldest packets stand at the end */
+       tfp = list_entry((head)->prev, typeof(*tfp), list);
+       kfree_skb(tfp->skb);
+
+       tfp->seqno = ntohs(up->seqno);
+       tfp->skb = skb;
+       list_move(&tfp->list, head);
+       return;
+}
+
+static int frag_create_buffer(struct list_head *head)
+{
+       int i;
+       struct frag_packet_list_entry *tfp;
+
+       for (i = 0; i < FRAG_BUFFER_SIZE; i++) {
+               tfp = kmalloc(sizeof(struct frag_packet_list_entry),
+                       GFP_ATOMIC);
+               if (!tfp) {
+                       frag_list_free(head);
+                       return -ENOMEM;
+               }
+               tfp->skb = NULL;
+               tfp->seqno = 0;
+               INIT_LIST_HEAD(&tfp->list);
+               list_add(&tfp->list, head);
+       }
+
+       return 0;
+}
+
+static struct frag_packet_list_entry *frag_search_packet(struct list_head *head,
+                                                struct unicast_frag_packet *up)
+{
+       struct frag_packet_list_entry *tfp;
+       struct unicast_frag_packet *tmp_up = NULL;
+       uint16_t search_seqno;
+
+       if (up->flags & UNI_FRAG_HEAD)
+               search_seqno = ntohs(up->seqno)+1;
+       else
+               search_seqno = ntohs(up->seqno)-1;
+
+       list_for_each_entry(tfp, head, list) {
+
+               if (!tfp->skb)
+                       continue;
+
+               if (tfp->seqno == ntohs(up->seqno))
+                       goto mov_tail;
+
+               tmp_up = (struct unicast_frag_packet *)tfp->skb->data;
+
+               if (tfp->seqno == search_seqno) {
+
+                       if ((tmp_up->flags & UNI_FRAG_HEAD) !=
+                           (up->flags & UNI_FRAG_HEAD))
+                               return tfp;
+                       else
+                               goto mov_tail;
+               }
+       }
+       return NULL;
+
+mov_tail:
+       list_move_tail(&tfp->list, head);
+       return NULL;
+}
+
+void frag_list_free(struct list_head *head)
+{
+       struct frag_packet_list_entry *pf, *tmp_pf;
+
+       if (!list_empty(head)) {
+
+               list_for_each_entry_safe(pf, tmp_pf, head, list) {
+                       kfree_skb(pf->skb);
+                       list_del(&pf->list);
+                       kfree(pf);
+               }
+       }
+       return;
+}
+
+/* frag_reassemble_skb():
+ * returns NET_RX_DROP if the operation failed - skb is left intact
+ * returns NET_RX_SUCCESS if the fragment was buffered (skb_new will be NULL)
+ * or the skb could be reassembled (skb_new will point to the new packet and
+ * skb was freed)
+ */
+int frag_reassemble_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
+                       struct sk_buff **new_skb)
+{
+       unsigned long flags;
+       struct orig_node *orig_node;
+       struct frag_packet_list_entry *tmp_frag_entry;
+       int ret = NET_RX_DROP;
+       struct unicast_frag_packet *unicast_packet =
+               (struct unicast_frag_packet *)skb->data;
+
+       *new_skb = NULL;
+       spin_lock_irqsave(&bat_priv->orig_hash_lock, flags);
+       orig_node = ((struct orig_node *)
+                   hash_find(bat_priv->orig_hash, unicast_packet->orig));
+
+       if (!orig_node) {
+               pr_debug("couldn't find originator in orig_hash\n");
+               goto out;
+       }
+
+       orig_node->last_frag_packet = jiffies;
+
+       if (list_empty(&orig_node->frag_list) &&
+           frag_create_buffer(&orig_node->frag_list)) {
+               pr_debug("couldn't create frag buffer\n");
+               goto out;
+       }
+
+       tmp_frag_entry = frag_search_packet(&orig_node->frag_list,
+                                           unicast_packet);
+
+       if (!tmp_frag_entry) {
+               frag_create_entry(&orig_node->frag_list, skb);
+               ret = NET_RX_SUCCESS;
+               goto out;
+       }
+
+       *new_skb = frag_merge_packet(&orig_node->frag_list, tmp_frag_entry,
+                                    skb);
+       /* if not, merge failed */
+       if (*new_skb)
+               ret = NET_RX_SUCCESS;
+out:
+       spin_unlock_irqrestore(&bat_priv->orig_hash_lock, flags);
+
+       return ret;
+}
+
+int frag_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv,
+                 struct batman_if *batman_if, uint8_t dstaddr[])
+{
+       struct unicast_packet tmp_uc, *unicast_packet;
+       struct sk_buff *frag_skb;
+       struct unicast_frag_packet *frag1, *frag2;
+       int uc_hdr_len = sizeof(struct unicast_packet);
+       int ucf_hdr_len = sizeof(struct unicast_frag_packet);
+       int data_len = skb->len;
+
+       if (!bat_priv->primary_if)
+               goto dropped;
+
+       unicast_packet = (struct unicast_packet *) skb->data;
+
+       memcpy(&tmp_uc, unicast_packet, uc_hdr_len);
+       frag_skb = dev_alloc_skb(data_len - (data_len / 2) + ucf_hdr_len);
+       skb_split(skb, frag_skb, data_len / 2);
+
+       if (my_skb_head_push(skb, ucf_hdr_len - uc_hdr_len) < 0 ||
+           my_skb_head_push(frag_skb, ucf_hdr_len) < 0)
+               goto drop_frag;
+
+       frag1 = (struct unicast_frag_packet *)skb->data;
+       frag2 = (struct unicast_frag_packet *)frag_skb->data;
+
+       memcpy(frag1, &tmp_uc, sizeof(struct unicast_packet));
+
+       frag1->ttl--;
+       frag1->version = COMPAT_VERSION;
+       frag1->packet_type = BAT_UNICAST_FRAG;
+
+       memcpy(frag1->orig, bat_priv->primary_if->net_dev->dev_addr, ETH_ALEN);
+       memcpy(frag2, frag1, sizeof(struct unicast_frag_packet));
+
+       frag1->flags |= UNI_FRAG_HEAD;
+       frag2->flags &= ~UNI_FRAG_HEAD;
+
+       frag1->seqno = htons((uint16_t)atomic_inc_return(
+                            &batman_if->frag_seqno));
+       frag2->seqno = htons((uint16_t)atomic_inc_return(
+                            &batman_if->frag_seqno));
+
+       send_skb_packet(skb, batman_if, dstaddr);
+       send_skb_packet(frag_skb, batman_if, dstaddr);
+       return NET_RX_SUCCESS;
+
+drop_frag:
+       kfree_skb(frag_skb);
+dropped:
+       kfree_skb(skb);
+       return NET_RX_DROP;
+}
+
 int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
 {
        struct ethhdr *ethhdr = (struct ethhdr *)skb->data;
@@ -35,19 +275,21 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
        struct orig_node *orig_node;
        struct batman_if *batman_if;
        struct neigh_node *router;
+       int data_len = skb->len;
        uint8_t dstaddr[6];
        unsigned long flags;
 
-       spin_lock_irqsave(&orig_hash_lock, flags);
+       spin_lock_irqsave(&bat_priv->orig_hash_lock, flags);
 
        /* get routing information */
-       orig_node = ((struct orig_node *)hash_find(orig_hash, ethhdr->h_dest));
+       orig_node = ((struct orig_node *)hash_find(bat_priv->orig_hash,
+                                                  ethhdr->h_dest));
 
        /* check for hna host */
        if (!orig_node)
-               orig_node = transtable_search(ethhdr->h_dest);
+               orig_node = transtable_search(bat_priv, ethhdr->h_dest);
 
-       router = find_router(orig_node, NULL);
+       router = find_router(bat_priv, orig_node, NULL);
 
        if (!router)
                goto unlock;
@@ -58,12 +300,12 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
        batman_if = router->if_incoming;
        memcpy(dstaddr, router->addr, ETH_ALEN);
 
-       spin_unlock_irqrestore(&orig_hash_lock, flags);
+       spin_unlock_irqrestore(&bat_priv->orig_hash_lock, flags);
 
        if (batman_if->if_status != IF_ACTIVE)
                goto dropped;
 
-       if (my_skb_push(skb, sizeof(struct unicast_packet)) < 0)
+       if (my_skb_head_push(skb, sizeof(struct unicast_packet)) < 0)
                goto dropped;
 
        unicast_packet = (struct unicast_packet *)skb->data;
@@ -76,11 +318,19 @@ int unicast_send_skb(struct sk_buff *skb, struct bat_priv *bat_priv)
        /* copy the destination for faster routing */
        memcpy(unicast_packet->dest, orig_node->orig, ETH_ALEN);
 
+       if (atomic_read(&bat_priv->fragmentation) &&
+           data_len + sizeof(struct unicast_packet) >
+           batman_if->net_dev->mtu) {
+               /* send frag skb decreases ttl */
+               unicast_packet->ttl++;
+               return frag_send_skb(skb, bat_priv, batman_if,
+                                    dstaddr);
+       }
        send_skb_packet(skb, batman_if, dstaddr);
        return 0;
 
 unlock:
-       spin_unlock_irqrestore(&orig_hash_lock, flags);
+       spin_unlock_irqrestore(&bat_priv->orig_hash_lock, flags);
 dropped:
        kfree_skb(skb);
        return 1;