From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Hutchings Subject: Re: [RFT PATCH 3/9] net: ethtool: break association of ETH_FLAG_* with NETIF_F_* Date: Mon, 20 Jun 2011 21:11:21 +0100 Message-ID: <1308600681.2701.159.camel@bwh-desktop> References: <51d2fd4cf6855c2285ca9bcd8d267abedcbc599c.1308596963.git.mirq-linux@rere.qmqm.pl> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: netdev@vger.kernel.org, "David S. Miller" , Stephen Hemminger To: =?UTF-8?Q?Micha=C5=82_Miros=C5=82aw?= Return-path: Received: from mail.solarflare.com ([216.237.3.220]:27804 "EHLO exchange.solarflare.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752454Ab1FTULY convert rfc822-to-8bit (ORCPT ); Mon, 20 Jun 2011 16:11:24 -0400 In-Reply-To: <51d2fd4cf6855c2285ca9bcd8d267abedcbc599c.1308596963.git.mirq-linux@rere.qmqm.pl> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, 2011-06-20 at 21:14 +0200, Micha=C5=82 Miros=C5=82aw wrote: > This is the only place where NETIF_F_* feature flags are exposed > to userspace. Except sysfs. > After this patch feature flags may be changed/reordered freely. [...] Really, what do you think was the point of exposing features through sysfs if they are going to be changed? Oh, but they have been changed already: v2.5.70 net-sysfs added v2.6.15 +#define NETIF_F_UFO 8192 /* Can offload UDP Large Send*= / v2.6.18 -#define NETIF_F_TSO 2048 /* Can offload TCP/IP segmentat= ion */ -#define NETIF_F_UFO 8192 /* Can offload UDP Large Send*= / +#define NETIF_F_GSO 2048 /* Enable software GSO. */ +#define NETIF_F_GSO_SHIFT 16 +#define NETIF_F_TSO (SKB_GSO_TCPV4 << NETIF_F_GSO_SHIFT) +#define NETIF_F_UFO (SKB_GSO_UDP << NETIF_F_GSO_SHIFT) +#define NETIF_F_GSO_ROBUST (SKB_GSO_DODGY << NETIF_F_GSO_SHIFT) +#define NETIF_F_TSO_ECN (SKB_GSO_TCP_ECN << NETIF_F_GSO= _SHIFT) +#define NETIF_F_TSO6 (SKB_GSO_TCPV6 << NETIF_F_GSO_SHIFT) v2.6.23 +#define NETIF_F_IPV6_CSUM 16 /* Can checksum TCP/UDP over IP= V6 */ +#define NETIF_F_MULTI_QUEUE 16384 /* Has multiple TX/RX queues */ v2.6.24 +#define NETIF_F_NETNS_LOCAL 8192 /* Does not change network name= spaces */ v2.6.27 -#define NETIF_F_MULTI_QUEUE 16384 /* Has multiple TX/RX queues */ v2.6.29 +#define NETIF_F_GRO 16384 /* Generic receive offload */ (I've omitted changes that use previously unused bits.) If we're going to keep changing features (maybe even more often) then w= e have to do something about this sysfs attribute. Maybe get rid of it (as it seems not to be widely used, thankfully). Maybe fix it to use the same feature values as today, but no new features. But certainly don't pretend that feature flags are not exposed. Ben. --=20 Ben Hutchings, Senior Software Engineer, Solarflare Not speaking for my employer; that's the marketing department's job. They asked us to note that Solarflare product names are trademarked.