lkml.org 
[lkml]   [2011]   [May]   [2]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH] ipheth.c: Enable IP header alignment
Date
Since commit ea812ca1b06113597adcd8e70c0f84a413d97544 (x86: Align skb w/ start
of cacheline on newer core 2/Xeon Arch), NET_IP_ALIGN changed from 2 to 0, and
the constant is used to reserve more room for the socket buffer.

Some people have reported that tethering stopped working and David Hill
submited a patch that redefined NET_IP_ALIGN. Pointed by Ben Hutchings, the
patch has been reworked to use a private constant.

I have no more an iPhone device to test it, so it is only compile-tested.

Signed-off-by: L. Alberto Giménez <agimenez@sysvalve.es>
---
drivers/net/usb/ipheth.c | 8 +++++---
1 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/drivers/net/usb/ipheth.c b/drivers/net/usb/ipheth.c
index 7d42f9a..8f1ffc7 100644
--- a/drivers/net/usb/ipheth.c
+++ b/drivers/net/usb/ipheth.c
@@ -80,6 +80,8 @@
#define IPHETH_CARRIER_CHECK_TIMEOUT round_jiffies_relative(1 * HZ)
#define IPHETH_CARRIER_ON 0x04

+#define IPHETH_IP_ALIGN 2
+
static struct usb_device_id ipheth_table[] = {
{ USB_DEVICE_AND_INTERFACE_INFO(
USB_VENDOR_APPLE, USB_PRODUCT_IPHONE,
@@ -205,15 +207,15 @@ static void ipheth_rcvbulk_callback(struct urb *urb)
len = urb->actual_length;
buf = urb->transfer_buffer;

- skb = dev_alloc_skb(NET_IP_ALIGN + len);
+ skb = dev_alloc_skb(IPHETH_IP_ALIGN + len);
if (!skb) {
err("%s: dev_alloc_skb: -ENOMEM", __func__);
dev->net->stats.rx_dropped++;
return;
}

- skb_reserve(skb, NET_IP_ALIGN);
- memcpy(skb_put(skb, len), buf + NET_IP_ALIGN, len - NET_IP_ALIGN);
+ skb_reserve(skb, IPHETH_IP_ALIGN);
+ memcpy(skb_put(skb, len), buf + IPHETH_IP_ALIGN, len - IPHETH_IP_ALIGN);
skb->dev = dev->net;
skb->protocol = eth_type_trans(skb, dev->net);

--
1.7.5
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2011-05-02 21:37    [W:0.086 / U:5.392 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site