From 05a56487174d33fff5986f13c0c8e4b32f046da9 Mon Sep 17 00:00:00 2001 From: Rafal Redzimski Date: Thu, 19 May 2016 11:56:09 +0200 Subject: [PATCH] net: cdc_ncm: update datagram size after changing mtu 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 Signed-off-by: David S. Miller --- 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 2fb31edab125..53759c315b97 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);