Return-path: Received: from nick.hrz.tu-chemnitz.de ([134.109.228.11]:51721 "EHLO nick.hrz.tu-chemnitz.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757850Ab3ICRne (ORCPT ); Tue, 3 Sep 2013 13:43:34 -0400 From: Simon Wunderlich To: linux-wireless@vger.kernel.org Cc: Johannes Berg , Mathias Kretschmer , Simon Wunderlich Subject: [PATCH 2/4] nl80211/cfg80211: enable DFS for IBSS mode Date: Tue, 3 Sep 2013 19:43:19 +0200 Message-Id: <1378230201-25446-3-git-send-email-siwu@hrz.tu-chemnitz.de> (sfid-20130903_194343_417711_4DB1344E) In-Reply-To: <1378230201-25446-1-git-send-email-siwu@hrz.tu-chemnitz.de> References: <1378230201-25446-1-git-send-email-siwu@hrz.tu-chemnitz.de> Sender: linux-wireless-owner@vger.kernel.org List-ID: To use DFS in IBSS mode, userspace is required to react to radar events. It can inform nl80211 that it is capable of doing so by adding a NL80211_ATTR_CONTROL_PORT_DFS attribute when joining the IBSS. If this attribute is supplied, DFS channels may be used if the driver supports it. Support will be checked even if a channel without DFS will be joined, as the channel might change later due to scan activity or channel switch announcements. Signed-off-by: Simon Wunderlich Signed-off-by: Mathias Kretschmer --- include/net/cfg80211.h | 6 ++++++ include/uapi/linux/nl80211.h | 7 +++++++ net/wireless/chan.c | 3 ++- net/wireless/ibss.c | 24 ++++++++++++++++++++---- net/wireless/nl80211.c | 8 ++++++-- net/wireless/util.c | 11 +++++++++-- 6 files changed, 50 insertions(+), 9 deletions(-) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 0a2aafe..b20e8ca 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -1656,6 +1656,9 @@ struct cfg80211_disassoc_request { * sets/clears %NL80211_STA_FLAG_AUTHORIZED. If true, the driver is * required to assume that the port is unauthorized until authorized by * user space. Otherwise, port is marked authorized by default. + * @control_port_dfs: whether user space controls DFS operation, i.e. + * changes the channel when a radar is detected. This is required + * to operate on DFS channels. * @basic_rates: bitmap of basic rates to use when creating the IBSS * @mcast_rate: per-band multicast rate index + 1 (0: disabled) * @ht_capa: HT Capabilities over-rides. Values set in ht_capa_mask @@ -1673,6 +1676,7 @@ struct cfg80211_ibss_params { bool channel_fixed; bool privacy; bool control_port; + bool control_port_dfs; int mcast_rate[IEEE80211_NUM_BANDS]; struct ieee80211_ht_cap ht_capa; struct ieee80211_ht_cap ht_capa_mask; @@ -3053,6 +3057,7 @@ struct cfg80211_cached_keys; * @conn: (private) cfg80211 software SME connection state machine data * @connect_keys: (private) keys to set after connection is established * @ibss_fixed: (private) IBSS is using fixed BSSID + * @ibss_dfs_possible: (private) IBSS may change to a DFS channel * @event_list: (private) list for internal event processing * @event_lock: (private) lock for event list */ @@ -3091,6 +3096,7 @@ struct wireless_dev { struct ieee80211_channel *channel; bool ibss_fixed; + bool ibss_dfs_possible; bool ps; int ps_timeout; diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index fde2c02..80e68e0 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -1496,6 +1496,11 @@ enum nl80211_commands { * @NL80211_ATTR_RXMGMT_FLAGS: flags for nl80211_send_mgmt(), u32. * As specified in the &enum nl80211_rxmgmt_flags. * + * @NL80211_ATTR_CONTROL_PORT_DFS: A flag indicating whether user space + * controls DFS operation in IBSS mode. If the flag is included in + * %NL80211_CMD_JOIN_IBSS request, the driver will allow use of DFS + * channels and reports radar events to userspace. + * * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use */ @@ -1806,6 +1811,8 @@ enum nl80211_attrs { NL80211_ATTR_RXMGMT_FLAGS, + NL80211_ATTR_CONTROL_PORT_DFS, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, diff --git a/net/wireless/chan.c b/net/wireless/chan.c index 80504e6..92cf75f 100644 --- a/net/wireless/chan.c +++ b/net/wireless/chan.c @@ -504,7 +504,8 @@ cfg80211_get_chan_state(struct wireless_dev *wdev, case NL80211_IFTYPE_ADHOC: if (wdev->current_bss) { *chan = wdev->current_bss->pub.channel; - *chanmode = wdev->ibss_fixed + *chanmode = (wdev->ibss_fixed && + !wdev->ibss_dfs_possible) ? CHAN_MODE_SHARED : CHAN_MODE_EXCLUSIVE; return; diff --git a/net/wireless/ibss.c b/net/wireless/ibss.c index 39bff7d..5edd69e 100644 --- a/net/wireless/ibss.c +++ b/net/wireless/ibss.c @@ -83,6 +83,8 @@ int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev, struct cfg80211_cached_keys *connkeys) { struct wireless_dev *wdev = dev->ieee80211_ptr; + struct ieee80211_channel *check_chan; + u8 radar_detect_width = 0; int err; ASSERT_WDEV_LOCK(wdev); @@ -114,14 +116,28 @@ int __cfg80211_join_ibss(struct cfg80211_registered_device *rdev, wdev->connect_keys = connkeys; wdev->ibss_fixed = params->channel_fixed; + wdev->ibss_dfs_possible = params->control_port_dfs; #ifdef CONFIG_CFG80211_WEXT wdev->wext.ibss.chandef = params->chandef; #endif + check_chan = params->chandef.chan; + if (params->control_port_dfs) { + /* use channel NULL to check for radar even if the current + * channel is not a radar channel - it might decide to change + * to DFS channel later. + */ + radar_detect_width = BIT(params->chandef.width); + check_chan = NULL; + } + + err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype, + check_chan, + (params->channel_fixed && + !radar_detect_width) + ? CHAN_MODE_SHARED + : CHAN_MODE_EXCLUSIVE, + radar_detect_width); - err = cfg80211_can_use_chan(rdev, wdev, params->chandef.chan, - params->channel_fixed - ? CHAN_MODE_SHARED - : CHAN_MODE_EXCLUSIVE); if (err) { wdev->connect_keys = NULL; return err; diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index cbbef88..d10410a 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -354,6 +354,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = { [NL80211_ATTR_CSA_IES] = { .type = NLA_NESTED }, [NL80211_ATTR_CSA_C_OFF_BEACON] = { .type = NLA_U16 }, [NL80211_ATTR_CSA_C_OFF_PRESP] = { .type = NLA_U16 }, + [NL80211_ATTR_CONTROL_PORT_DFS] = { .type = NLA_FLAG }, }; /* policy for the key attributes */ @@ -5722,9 +5723,9 @@ skip_beacons: if (!cfg80211_reg_can_beacon(&rdev->wiphy, ¶ms.chandef)) return -EINVAL; - /* DFS channels are only supported for AP/P2P GO ... for now. */ if (dev->ieee80211_ptr->iftype == NL80211_IFTYPE_AP || - dev->ieee80211_ptr->iftype == NL80211_IFTYPE_P2P_GO) { + dev->ieee80211_ptr->iftype == NL80211_IFTYPE_P2P_GO || + dev->ieee80211_ptr->iftype == NL80211_IFTYPE_ADHOC) { err = cfg80211_chandef_dfs_required(wdev->wiphy, ¶ms.chandef); if (err < 0) { @@ -6556,6 +6557,9 @@ static int nl80211_join_ibss(struct sk_buff *skb, struct genl_info *info) ibss.control_port = nla_get_flag(info->attrs[NL80211_ATTR_CONTROL_PORT]); + ibss.control_port_dfs = + nla_get_flag(info->attrs[NL80211_ATTR_CONTROL_PORT_DFS]); + err = cfg80211_join_ibss(rdev, dev, &ibss, connkeys); if (err) kfree(connkeys); diff --git a/net/wireless/util.c b/net/wireless/util.c index ce090c1..beee988 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -1255,8 +1255,15 @@ int cfg80211_can_use_iftype_chan(struct cfg80211_registered_device *rdev, case NL80211_IFTYPE_MESH_POINT: case NL80211_IFTYPE_P2P_GO: case NL80211_IFTYPE_WDS: - radar_required = !!(chan && - (chan->flags & IEEE80211_CHAN_RADAR)); + /* if the interface could potentially choose a DFS channel, + * then mark DFS as required. + */ + if (!chan) { + if (chanmode != CHAN_MODE_UNDEFINED && radar_detect) + radar_required = true; + break; + } + radar_required = !!(chan->flags & IEEE80211_CHAN_RADAR); break; case NL80211_IFTYPE_P2P_CLIENT: case NL80211_IFTYPE_STATION: -- 1.7.10.4