Return-path: Received: from mail-wg0-f51.google.com ([74.125.82.51]:40125 "EHLO mail-wg0-f51.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750856AbaKZQuA (ORCPT ); Wed, 26 Nov 2014 11:50:00 -0500 Received: by mail-wg0-f51.google.com with SMTP id k14so4208323wgh.24 for ; Wed, 26 Nov 2014 08:49:59 -0800 (PST) MIME-Version: 1.0 In-Reply-To: References: <1416754941-4439-1-git-send-email-arik@wizery.com> <1416754941-4439-3-git-send-email-arik@wizery.com> <20141125202847.GL25677@wotan.suse.de> From: Arik Nemtsov Date: Wed, 26 Nov 2014 18:49:43 +0200 Message-ID: (sfid-20141126_175006_205990_B37303FF) Subject: Re: [PATCH v3 3/3] cfg80211: Allow usermode to query wiphy specific regd info To: "Luis R. Rodriguez" Cc: "linux-wireless@vger.kernel.org" , Johannes Berg , Jonathan Doron Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Nov 26, 2014 at 6:47 PM, Luis R. Rodriguez wrote: > On Wed, Nov 26, 2014 at 11:43 AM, Arik Nemtsov wrote: >> On Tue, Nov 25, 2014 at 10:28 PM, Luis R. Rodriguez wrote: >>> On Sun, Nov 23, 2014 at 05:02:21PM +0200, Arik Nemtsov wrote: >>>> From: Jonathan Doron >>>> >>>> Allow usermode to query wiphy-specific regd info, for drivers that use >>>> wiphy-specific regulatory management. >>>> >>>> Use the existing API for sending regdomain info to usermode, but return >>>> the wiphy-specific regd in case wiphy index is provided and the driver >>>> employs wiphy-specific management. This implies user and kernel-mode >>>> support for the feature and is backward compatible. >>>> >>>> Signed-off-by: Jonathan Doron >>>> Signed-off-by: Arik Nemtsov >>>> --- >>>> include/uapi/linux/nl80211.h | 18 ++++++++++- >>>> net/wireless/nl80211.c | 71 ++++++++++++++++++++++++++++++++++++-------- >>>> net/wireless/reg.c | 2 +- >>>> net/wireless/reg.h | 1 + >>>> 4 files changed, 78 insertions(+), 14 deletions(-) >>>> >>>> diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h >>>> index 3771e7d..b222e5c 100644 >>>> --- a/include/uapi/linux/nl80211.h >>>> +++ b/include/uapi/linux/nl80211.h >>>> @@ -252,7 +252,12 @@ >>>> * %NL80211_ATTR_IFINDEX. >>>> * >>>> * @NL80211_CMD_GET_REG: ask the wireless core to send us its currently set >>>> - * regulatory domain. >>>> + * regulatory domain. If %NL80211_ATTR_WIPHY is specified and the device >>>> + * self-manages its regulatory settings, its private regulatory domain >>>> + * will be returned. >>>> + * If %NL80211_ATTR_WIPHY_GET_PRIV_REG is specified in addition to >>>> + * %NL80211_ATTR_WIPHY, a device's private regulatory domain will be >>>> + * returned, even if it's regulatory is not self-managed. >>>> * @NL80211_CMD_SET_REG: Set current regulatory domain. CRDA sends this command >>>> * after being queried by the kernel. CRDA replies by sending a regulatory >>>> * domain structure which consists of %NL80211_ATTR_REG_ALPHA set to our >>>> @@ -1693,6 +1698,14 @@ enum nl80211_commands { >>>> * >>>> * @NL80211_ATTR_MAC_MASK: MAC address mask >>>> * >>>> + * @NL80211_ATTR_WIPHY_SELF_MANAGED_REG: flag attribute indicating the >>>> + * regulatory information was obtained from the private regdomain >>>> + * of a device with self-managed regulatory. >>>> + * @NL80211_ATTR_WIPHY_GET_PRIV_REG: flag attribute indicating the regulatory >>>> + * information should be obtained from a device's private regdomain, >>>> + * if it exists. This will happen even if the device is not self-managing >>>> + * its regulatory. >>> >>> As with REGULATORY_WIPHY_SELF_MANAGED we need a flag that cfg80211 sets for >>> drivers that use regulatory_hint() API, perhaps REGULATORY_WIPHY_REG_HINT. >>> Then this can be used by cfg80211 to send to userspace regdomains for wiphys >>> that have used this API. Below you enable userspace to only query for these >>> explictly but we want to be able to let userspace get all information, ie >>> through 'iw reg get'. This should go in as a separate patch along with >>> NL80211_ATTR_WIPHY_GET_PRIV_REG as its use predates >>> NL80211_ATTR_WIPHY_SELF_MANAGED_REG, this will also let you stuff in the boiler >>> plate code for getting that reg first, getting self managed regd's can then >>> go in as a clear secondary evolutionary step. >> >> Note that we don't really need the new REGULATORY_WIPHY_REG_HINT.. If >> a wiphy is not self-managed, we can just put >> NL80211_ATTR_WIPHY_PRIV_REG, since it's obvious the regulatory_hint >> API was used. > > What if a driver sets the managed flag and then uses regulatory_hint() > ? Either way if this is addressed and we can also infer what type of > wiphy->regd it is well that's OK with me, the flag idea was just in > case we needed it, so I think you might be right. A self-managed device can't use regulatory_hint().. This is the regular path which also updates the cfg80211 regdomain. If a device tries to do that, the new regd from CRDA will never reach it. So we're covered here. Arik