From: Ulrich Kunitz <kune@deine-taler.de>
Date: Wed, 22 Nov 2006 00:06:19 +0000 (+0000)
Subject: [PATCH] zd1211rw: Optimized handling of zero length entries in length info
X-Git-Tag: v2.6.20-rc2~6^2~13^2~468^2~39
X-Git-Url: http://pilppa.com/gitweb/?a=commitdiff_plain;h=850c211ce6948bcd71e505be22b7ead99a425bfa;p=linux-2.6-omap-h63xx.git

[PATCH] zd1211rw: Optimized handling of zero length entries in length info

There are a high number of split USB transactions, which contain
only one packet but have a length info field. This patch optimizes
this code by stopping parsing the length info structure if a zero
length field is encountered.

Signed-off-by: Ulrich Kunitz <kune@deine-taler.de>
Signed-off-by: Daniel Drake <dsd@gentoo.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
---

diff --git a/drivers/net/wireless/zd1211rw/zd_usb.c b/drivers/net/wireless/zd1211rw/zd_usb.c
index c3449cfae7e..aa782e88754 100644
--- a/drivers/net/wireless/zd1211rw/zd_usb.c
+++ b/drivers/net/wireless/zd1211rw/zd_usb.c
@@ -593,6 +593,8 @@ static void handle_rx_packet(struct zd_usb *usb, const u8 *buffer,
 		unsigned int l, k, n;
 		for (i = 0, l = 0;; i++) {
 			k = le16_to_cpu(get_unaligned(&length_info->length[i]));
+			if (k == 0)
+				return;
 			n = l+k;
 			if (n > length)
 				return;