From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robert Dobrowolski Subject: [PATCH net,stable v2] net: cdc_ncm: update datagram size after changing mtu Date: Thu, 19 May 2016 11:56:09 +0200 Message-ID: <1463651769-27513-1-git-send-email-robert.dobrowolski@linux.intel.com> Cc: robert.dobrowolski@linux.intel.com, stable@vger.kernel.org, oliver@neukum.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Rafal Redzimski To: linux-usb@vger.kernel.org Return-path: Received: from mga11.intel.com ([192.55.52.93]:34775 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754095AbcESJ64 (ORCPT ); Thu, 19 May 2016 05:58:56 -0400 Sender: netdev-owner@vger.kernel.org List-ID: From: Rafal Redzimski Current implementation updates the mtu size and notify cdc_ncm device using USB_CDC_SET_MAX_DATAGRAM_SIZE request about datagram size change instead of changing rx_urb_size. Whenever mtu is being changed, datagram size should also be updated. Also updating maxmtu formula so it takes max_datagram_size with use of cdc_ncm_max_dgram_size() and not ctx. Signed-off-by: Robert Dobrowolski Signed-off-by: Rafal Redzimski --- Changes in v2: - Changed the way maxmtu is being calculated. Its now based on cdc_ncm_max_dgram_size and not on ctx->max_datagram_size. New datagram size is calculated correctly. drivers/net/usb/cdc_ncm.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/usb/cdc_ncm.c b/drivers/net/usb/cdc_ncm.c index 2fb31ed..53759c3 100644 --- a/drivers/net/usb/cdc_ncm.c +++ b/drivers/net/usb/cdc_ncm.c @@ -740,12 +740,14 @@ static void cdc_ncm_free(struct cdc_ncm_ctx *ctx) int cdc_ncm_change_mtu(struct net_device *net, int new_mtu) { struct usbnet *dev = netdev_priv(net); - struct cdc_ncm_ctx *ctx = (struct cdc_ncm_ctx *)dev->data[0]; - int maxmtu = ctx->max_datagram_size - cdc_ncm_eth_hlen(dev); + int maxmtu = cdc_ncm_max_dgram_size(dev) - cdc_ncm_eth_hlen(dev); if (new_mtu <= 0 || new_mtu > maxmtu) return -EINVAL; + net->mtu = new_mtu; + cdc_ncm_set_dgram_size(dev, new_mtu + cdc_ncm_eth_hlen(dev)); + return 0; } EXPORT_SYMBOL_GPL(cdc_ncm_change_mtu); -- 1.9.1