system/linux
system/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux synced 2024-09-06 18:01:05 +00:00
Code Issues Packages Projects Releases Wiki Activity

Phonet: zero-copy aligned GPRS RX

Browse source 
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>
This commit is contained in:
Rémi Denis-Courmont 2010-01-04 02:02:47 +00:00 committed by David S. Miller
parent f6de7acc42
commit fc6a110754
3 changed files with 6 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

1
include/net/phonet/pep.h
View file

@ -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,

4
net/phonet/pep-gprs.c
View file

@ -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. */

3
net/phonet/pep.c
View file

@ -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)) {