Commit 212bfb9e authored by David S. Miller's avatar David S. Miller
Browse files

ppp: Reconstruct fragmented packets using frag lists instead of copying. 



[paulus@samba.org: fixed a couple of bugs]

Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent b48f8c23

drivers/net/ppp_generic.c

+23 −16
Original line number Diff line number Diff line
@@ -2055,16 +2055,6 @@ ppp_mp_reconstruct(struct ppp *ppp) 
				netdev_printk(KERN_DEBUG, ppp->dev,

					      "PPP: reconstructed packet"

					      " is too long (%d)\n", len);

			} else if (p == head) {

				/* fragment is complete packet - reuse skb */

				tail = p;

				skb = skb_get(p);

				break;

			} else if ((skb = dev_alloc_skb(len)) == NULL) {

				++ppp->dev->stats.rx_missed_errors;

				netdev_printk(KERN_DEBUG, ppp->dev,

					      "PPP: no memory for "

					      "reconstructed packet");

			} else {

				tail = p;

				break;
@@ -2097,16 +2087,33 @@ ppp_mp_reconstruct(struct ppp *ppp) 
			ppp_receive_error(ppp);

		}



		if (head != tail)

			/* copy to a single skb */

			for (p = head; p != tail->next; p = p->next)

				skb_copy_bits(p, 0, skb_put(skb, p->len), p->len);

		skb = head;

		if (head != tail) {

			struct sk_buff **fragpp = &skb_shinfo(skb)->frag_list;

			p = skb_queue_next(list, head);

			__skb_unlink(skb, list);

			skb_queue_walk_from_safe(list, p, tmp) {

				__skb_unlink(p, list);

				*fragpp = p;

				p->next = NULL;

				fragpp = &p->next;



				skb->len += p->len;

				skb->data_len += p->len;

				skb->truesize += p->len;



				if (p == tail)

					break;

			}

		} else {

			__skb_unlink(skb, list);

		}



		ppp->nextseq = PPP_MP_CB(tail)->sequence + 1;

		head = tail->next;

	}



	/* Discard all the skbuffs that we have copied the data out of

	   or that we can't use. */

	/* Discard all the skbuffs that we can't use. */

	while ((p = list->next) != head) {

		__skb_unlink(p, list);

		kfree_skb(p);