Commit fc6a1107 authored Jan 04, 2010 by Rémi Denis-Courmont Committed by David S. Miller Jan 07, 2010

Phonet: zero-copy aligned GPRS RX

Newer Nokia cellular modems can use aligned payload for their GPRS pipe.

Signed-off-by: Rémi Denis-Courmont <remi.denis-courmont@nokia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent f6de7acc

include/net/phonet/pep.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -77,6 +77,7 @@ static inline struct pnpipehdr pnp_hdr(struct sk_buff skb)

		enum {
		PNS_PIPE_DATA = 0x20,
		PNS_PIPE_ALIGNED_DATA,

		PNS_PEP_CONNECT_REQ = 0x40,
		PNS_PEP_CONNECT_RESP,

net/phonet/pep-gprs.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -96,11 +96,11 @@ static int gprs_recv(struct gprs_dev gp, struct sk_buff skb)
		goto drop;
		}

		if (likely(skb_headroom(skb) & 3)) {
		if (skb_headroom(skb) & 3) {
		struct sk_buff rskb, fs;
		int flen = 0;

		/* Phonet Pipe data header is misaligned (3 bytes),
		/* Phonet Pipe data header may be misaligned (3 bytes),
		* so wrap the IP packet as a single fragment of an head-less
		* socket buffer. The network stack will pull what it needs,
		* but at least, the whole IP payload is not memcpy'd. */

net/phonet/pep.c

+3 −0

Original line number	Diff line number	Diff line
		@@ -354,6 +354,9 @@ static int pipe_do_rcv(struct sock sk, struct sk_buff skb)
		queue = &pn->ctrlreq_queue;
		goto queue;

		case PNS_PIPE_ALIGNED_DATA:
		__skb_pull(skb, 1);
		/* fall through */
		case PNS_PIPE_DATA:
		__skb_pull(skb, 3); /* Pipe data header */
		if (!pn_flow_safe(pn->rx_fc)) {