Return-path: Received: from alexa-out.qualcomm.com ([129.46.98.28]:41302 "EHLO alexa-out.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752871AbdLVQef (ORCPT ); Fri, 22 Dec 2017 11:34:35 -0500 From: Jouni Malinen To: Johannes Berg CC: , Sunil Dutt , Jouni Malinen Subject: [PATCH v2 3/3] nl80211: Introduce scan flags to emphasize requested scan behavior Date: Fri, 22 Dec 2017 18:33:39 +0200 Message-ID: <1513960419-24780-3-git-send-email-jouni@qca.qualcomm.com> (sfid-20171222_173438_131853_C96E0BF9) In-Reply-To: <1513960419-24780-1-git-send-email-jouni@qca.qualcomm.com> References: <1513960419-24780-1-git-send-email-jouni@qca.qualcomm.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: From: Sunil Dutt This commit defines new scan flags (LOW_SPAN, LOW_POWER, HIGH_LATENCY) to emphasize the requested scan behavior for the driver. These flags are optional and are mutually exclusive. The implementation of the respective functionality can be driver/hardware specific. These flags can be used to control the compromise between how long a scan takes, how much power it uses, and high accurate/complete the scan is in finding the BSSs. Signed-off-by: Sunil Dutt Signed-off-by: Jouni Malinen --- include/uapi/linux/nl80211.h | 28 +++++++++++++++++++++++++++- net/wireless/nl80211.c | 13 +++++++++++-- 2 files changed, 38 insertions(+), 3 deletions(-) v2: - added driver capability flags to indicate which of the options are supported - added to this patch series due to a new dependency in one of the header files diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index 083c6c1..56e6bc0 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -4979,6 +4979,9 @@ enum nl80211_feature_flags { * @NL80211_EXT_FEATURE_MFP_OPTIONAL: Driver supports the %NL80211_MFP_OPTIONAL * value in %NL80211_ATTR_USE_MFP. * @NL80211_EXT_FEATURE_EXTERNAL_AUTH: Driver supports external authentication + * @NL80211_EXT_FEATURE_LOW_SPAN_SCAN: Driver supports low span scan. + * @NL80211_EXT_FEATURE_LOW_POWER_SCAN: Driver supports low power scan. + * @NL80211_EXT_FEATURE_HIGH_ACCURACY_SCAN: Driver supports high accuracy scan. * * @NUM_NL80211_EXT_FEATURES: number of extended features. * @MAX_NL80211_EXT_FEATURES: highest extended feature index. @@ -5007,6 +5010,9 @@ enum nl80211_ext_feature_index { NL80211_EXT_FEATURE_OCE_PROBE_REQ_DEFERRAL_SUPPRESSION, NL80211_EXT_FEATURE_MFP_OPTIONAL, NL80211_EXT_FEATURE_EXTERNAL_AUTH, + NL80211_EXT_FEATURE_LOW_SPAN_SCAN, + NL80211_EXT_FEATURE_LOW_POWER_SCAN, + NL80211_EXT_FEATURE_HIGH_ACCURACY_SCAN, /* add new features before the definition below */ NUM_NL80211_EXT_FEATURES, @@ -5067,6 +5073,10 @@ enum nl80211_timeout_reason { * of NL80211_CMD_TRIGGER_SCAN and NL80211_CMD_START_SCHED_SCAN * requests. * + * NL80211_SCAN_FLAG_LOW_SPAN, NL80211_SCAN_FLAG_LOW_POWER, and + * NL80211_SCAN_FLAG_HIGH_ACCURACY flags are exclusive of each other, i.e., only + * one of them can be used in the request. + * * @NL80211_SCAN_FLAG_LOW_PRIORITY: scan request has low priority * @NL80211_SCAN_FLAG_FLUSH: flush cache before scanning * @NL80211_SCAN_FLAG_AP: force a scan even if the interface is configured @@ -5094,7 +5104,20 @@ enum nl80211_timeout_reason { * and suppression (if it has received a broadcast Probe Response frame, * Beacon frame or FILS Discovery frame from an AP that the STA considers * a suitable candidate for (re-)association - suitable in terms of - * SSID and/or RSSI + * SSID and/or RSSI. + * @NL80211_SCAN_FLAG_LOW_SPAN: Span corresponds to the total time taken to + * accomplish the scan. Thus, this flag intends the driver to perform the + * scan request with lesser span/duration. It is specific to the driver + * implementations on how this is accomplished. Scan accuracy may get + * impacted with this flag. + * @NL80211_SCAN_FLAG_LOW_POWER: This flag intends the scan attempts to consume + * optimal possible power. Drivers can resort to their specific means to + * optimize the power. Scan accuracy may get impacted with this flag. + * @NL80211_SCAN_FLAG_HIGH_ACCURACY: Accuracy here intends to the extent of scan + * results obtained. Thus HIGH_ACCURACY scan flag aims to get maximum + * possible scan results. This flag hints the driver to use the best + * possible scan configuration to improve the accuracy in scanning. + * Latency and power use may get impacted with this flag. */ enum nl80211_scan_flags { NL80211_SCAN_FLAG_LOW_PRIORITY = 1<<0, @@ -5105,6 +5128,9 @@ enum nl80211_scan_flags { NL80211_SCAN_FLAG_ACCEPT_BCAST_PROBE_RESP = 1<<5, NL80211_SCAN_FLAG_OCE_PROBE_REQ_HIGH_TX_RATE = 1<<6, NL80211_SCAN_FLAG_OCE_PROBE_REQ_DEFERRAL_SUPPRESSION = 1<<7, + NL80211_SCAN_FLAG_LOW_SPAN = 1<<8, + NL80211_SCAN_FLAG_LOW_POWER = 1<<9, + NL80211_SCAN_FLAG_HIGH_ACCURACY = 1<<10, }; /** diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index ea36514..8a53e6e 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -6712,8 +6712,17 @@ nl80211_check_scan_flags(struct wiphy *wiphy, struct wireless_dev *wdev, *flags = nla_get_u32(attrs[NL80211_ATTR_SCAN_FLAGS]); - if ((*flags & NL80211_SCAN_FLAG_LOW_PRIORITY) && - !(wiphy->features & NL80211_FEATURE_LOW_PRIORITY_SCAN)) + if (((*flags & NL80211_SCAN_FLAG_LOW_PRIORITY) && + !(wiphy->features & NL80211_FEATURE_LOW_PRIORITY_SCAN)) || + ((*flags & NL80211_SCAN_FLAG_LOW_SPAN) && + !wiphy_ext_feature_isset(wiphy, + NL80211_EXT_FEATURE_LOW_SPAN_SCAN)) || + ((*flags & NL80211_SCAN_FLAG_LOW_POWER) && + !wiphy_ext_feature_isset(wiphy, + NL80211_EXT_FEATURE_LOW_POWER_SCAN)) || + ((*flags & NL80211_SCAN_FLAG_HIGH_ACCURACY) && + !wiphy_ext_feature_isset(wiphy, + NL80211_EXT_FEATURE_HIGH_ACCURACY_SCAN))) return -EOPNOTSUPP; if (*flags & NL80211_SCAN_FLAG_RANDOM_ADDR) { -- 2.7.4