From: Lorenzo Bianconi Date: Sat, 23 Oct 2021 11:10:50 +0200 Subject: [PATCH] cfg80211: implement APIs for dedicated radar detection HW If a dedicated (off-channel) radar detection hardware (chain) is available in the hardware/driver, allow this to be used by calling the NL80211_CMD_RADAR_DETECT command with a new flag attribute requesting off-channel radar detection is used. Offchannel CAC (channel availability check) avoids the CAC downtime when switching to a radar channel or when turning on the AP. Drivers advertise support for this using the new feature flag NL80211_EXT_FEATURE_RADAR_OFFCHAN. Tested-by: Evelyn Tsai Signed-off-by: Lorenzo Bianconi Link: https://lore.kernel.org/r/7468e291ef5d05d692c1738d25b8f778d8ea5c3f.1634979655.git.lorenzo@kernel.org Link: https://lore.kernel.org/r/1e60e60fef00e14401adae81c3d49f3e5f307537.1634979655.git.lorenzo@kernel.org Link: https://lore.kernel.org/r/85fa50f57fc3adb2934c8d9ca0be30394de6b7e8.1634979655.git.lorenzo@kernel.org Link: https://lore.kernel.org/r/4b6c08671ad59aae0ac46fc94c02f31b1610eb72.1634979655.git.lorenzo@kernel.org Link: https://lore.kernel.org/r/241849ccaf2c228873c6f8495bf87b19159ba458.1634979655.git.lorenzo@kernel.org [remove offchan_mutex, fix cfg80211_stop_offchan_radar_detection(), remove gfp_t argument, fix documentation, fix tracing] Signed-off-by: Johannes Berg --- --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -4057,6 +4057,15 @@ struct mgmt_frame_regs { * @set_sar_specs: Update the SAR (TX power) settings. * * @color_change: Initiate a color change. + * + * @set_radar_offchan: Configure dedicated offchannel chain available for + * radar/CAC detection on some hw. This chain can't be used to transmit + * or receive frames and it is bounded to a running wdev. + * Offchannel radar/CAC detection allows to avoid the CAC downtime + * switching to a different channel during CAC detection on the selected + * radar channel. + * The caller is expected to set chandef pointer to NULL in order to + * disable offchannel CAC/radar detection. */ struct cfg80211_ops { int (*suspend)(struct wiphy *wiphy, struct cfg80211_wowlan *wow); @@ -4387,6 +4396,8 @@ struct cfg80211_ops { int (*color_change)(struct wiphy *wiphy, struct net_device *dev, struct cfg80211_color_change_settings *params); + int (*set_radar_offchan)(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef); }; /* @@ -7608,6 +7619,20 @@ void cfg80211_cac_event(struct net_devic const struct cfg80211_chan_def *chandef, enum nl80211_radar_event event, gfp_t gfp); +/** + * cfg80211_offchan_cac_event - Channel Availability Check (CAC) offchan event + * @wiphy: the wiphy + * @chandef: chandef for the current channel + * @event: type of event + * + * This function is called when a Channel Availability Check (CAC) is finished, + * started or aborted by a offchannel dedicated chain. + * + * Note that this acquires the wiphy lock. + */ +void cfg80211_offchan_cac_event(struct wiphy *wiphy, + const struct cfg80211_chan_def *chandef, + enum nl80211_radar_event event); /** * cfg80211_gtk_rekey_notify - notify userspace about driver rekeying --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -2608,6 +2608,13 @@ enum nl80211_commands { * Mandatory parameter for the transmitting interface to enable MBSSID. * Optional for the non-transmitting interfaces. * + * @NL80211_ATTR_RADAR_OFFCHAN: Configure dedicated offchannel chain available for + * radar/CAC detection on some hw. This chain can't be used to transmit + * or receive frames and it is bounded to a running wdev. + * Offchannel radar/CAC detection allows to avoid the CAC downtime + * switching on a different channel during CAC detection on the selected + * radar channel. + * * @NUM_NL80211_ATTR: total number of nl80211_attrs available * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use @@ -3114,6 +3121,8 @@ enum nl80211_attrs { NL80211_ATTR_MBSSID_CONFIG, NL80211_ATTR_MBSSID_ELEMS, + NL80211_ATTR_RADAR_OFFCHAN, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, @@ -6013,6 +6022,9 @@ enum nl80211_feature_flags { * @NL80211_EXT_FEATURE_BSS_COLOR: The driver supports BSS color collision * detection and change announcemnts. * + * @NL80211_EXT_FEATURE_RADAR_OFFCHAN: Device supports offchannel radar/CAC + * detection. + * * @NUM_NL80211_EXT_FEATURES: number of extended features. * @MAX_NL80211_EXT_FEATURES: highest extended feature index. */ @@ -6078,6 +6090,7 @@ enum nl80211_ext_feature_index { NL80211_EXT_FEATURE_SECURE_RTT, NL80211_EXT_FEATURE_PROT_RANGE_NEGO_AND_MEASURE, NL80211_EXT_FEATURE_BSS_COLOR, + NL80211_EXT_FEATURE_RADAR_OFFCHAN, /* add new features before the definition below */ NUM_NL80211_EXT_FEATURES, --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -543,6 +543,7 @@ use_default_name: INIT_WORK(&rdev->rfkill_block, cfg80211_rfkill_block_work); INIT_WORK(&rdev->conn_work, cfg80211_conn_work); INIT_WORK(&rdev->event_work, cfg80211_event_work); + INIT_DELAYED_WORK(&rdev->offchan_cac_work, cfg80211_offchan_cac_work); init_waitqueue_head(&rdev->dev_wait); @@ -1205,6 +1206,8 @@ void __cfg80211_leave(struct cfg80211_re cfg80211_pmsr_wdev_down(wdev); + cfg80211_stop_offchan_radar_detection(wdev); + switch (wdev->iftype) { case NL80211_IFTYPE_ADHOC: __cfg80211_leave_ibss(rdev, dev, true); --- a/net/wireless/core.h +++ b/net/wireless/core.h @@ -84,6 +84,10 @@ struct cfg80211_registered_device { struct delayed_work dfs_update_channels_wk; + struct wireless_dev *offchan_radar_wdev; + struct cfg80211_chan_def offchan_radar_chandef; + struct delayed_work offchan_cac_work; + /* netlink port which started critical protocol (0 means not started) */ u32 crit_proto_nlportid; @@ -491,6 +495,15 @@ cfg80211_chandef_dfs_cac_time(struct wip void cfg80211_sched_dfs_chan_update(struct cfg80211_registered_device *rdev); +int +cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + struct cfg80211_chan_def *chandef); + +void cfg80211_stop_offchan_radar_detection(struct wireless_dev *wdev); + +void cfg80211_offchan_cac_work(struct work_struct *work); + bool cfg80211_any_wiphy_oper_chan(struct wiphy *wiphy, struct ieee80211_channel *chan); --- a/net/wireless/mlme.c +++ b/net/wireless/mlme.c @@ -970,3 +970,116 @@ void cfg80211_cac_event(struct net_devic nl80211_radar_notify(rdev, chandef, event, netdev, gfp); } EXPORT_SYMBOL(cfg80211_cac_event); + +void cfg80211_offchan_cac_work(struct work_struct *work) +{ + struct delayed_work *delayed_work = to_delayed_work(work); + struct cfg80211_registered_device *rdev; + + rdev = container_of(delayed_work, struct cfg80211_registered_device, + offchan_cac_work); + cfg80211_offchan_cac_event(&rdev->wiphy, &rdev->offchan_radar_chandef, + NL80211_RADAR_CAC_FINISHED); +} + +static void +__cfg80211_offchan_cac_event(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + const struct cfg80211_chan_def *chandef, + enum nl80211_radar_event event) +{ + struct wiphy *wiphy = &rdev->wiphy; + struct net_device *netdev; + + lockdep_assert_wiphy(&rdev->wiphy); + + if (event != NL80211_RADAR_CAC_STARTED && !rdev->offchan_radar_wdev) + return; + + switch (event) { + case NL80211_RADAR_CAC_FINISHED: + cfg80211_set_dfs_state(wiphy, chandef, NL80211_DFS_AVAILABLE); + memcpy(&rdev->cac_done_chandef, chandef, sizeof(*chandef)); + queue_work(cfg80211_wq, &rdev->propagate_cac_done_wk); + cfg80211_sched_dfs_chan_update(rdev); + wdev = rdev->offchan_radar_wdev; + rdev->offchan_radar_wdev = NULL; + break; + case NL80211_RADAR_CAC_ABORTED: + cancel_delayed_work(&rdev->offchan_cac_work); + wdev = rdev->offchan_radar_wdev; + rdev->offchan_radar_wdev = NULL; + break; + case NL80211_RADAR_CAC_STARTED: + WARN_ON(!wdev); + rdev->offchan_radar_wdev = wdev; + break; + default: + return; + } + + netdev = wdev ? wdev->netdev : NULL; + nl80211_radar_notify(rdev, chandef, event, netdev, GFP_KERNEL); +} + +void cfg80211_offchan_cac_event(struct wiphy *wiphy, + const struct cfg80211_chan_def *chandef, + enum nl80211_radar_event event) +{ + struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); + + wiphy_lock(wiphy); + __cfg80211_offchan_cac_event(rdev, NULL, chandef, event); + wiphy_unlock(wiphy); +} +EXPORT_SYMBOL(cfg80211_offchan_cac_event); + +int +cfg80211_start_offchan_radar_detection(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + struct cfg80211_chan_def *chandef) +{ + unsigned int cac_time_ms; + int err; + + lockdep_assert_wiphy(&rdev->wiphy); + + if (!wiphy_ext_feature_isset(&rdev->wiphy, + NL80211_EXT_FEATURE_RADAR_OFFCHAN)) + return -EOPNOTSUPP; + + if (rdev->offchan_radar_wdev) + return -EBUSY; + + err = rdev_set_radar_offchan(rdev, chandef); + if (err) + return err; + + cac_time_ms = cfg80211_chandef_dfs_cac_time(&rdev->wiphy, chandef); + if (!cac_time_ms) + cac_time_ms = IEEE80211_DFS_MIN_CAC_TIME_MS; + + rdev->offchan_radar_chandef = *chandef; + __cfg80211_offchan_cac_event(rdev, wdev, chandef, + NL80211_RADAR_CAC_STARTED); + queue_delayed_work(cfg80211_wq, &rdev->offchan_cac_work, + msecs_to_jiffies(cac_time_ms)); + + return 0; +} + +void cfg80211_stop_offchan_radar_detection(struct wireless_dev *wdev) +{ + struct wiphy *wiphy = wdev->wiphy; + struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); + + lockdep_assert_wiphy(wiphy); + + if (wdev != rdev->offchan_radar_wdev) + return; + + rdev_set_radar_offchan(rdev, NULL); + + __cfg80211_offchan_cac_event(rdev, NULL, NULL, + NL80211_RADAR_CAC_ABORTED); +} --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -801,6 +801,7 @@ static const struct nla_policy nl80211_p [NL80211_ATTR_MBSSID_CONFIG] = NLA_POLICY_NESTED(nl80211_mbssid_config_policy), [NL80211_ATTR_MBSSID_ELEMS] = { .type = NLA_NESTED }, + [NL80211_ATTR_RADAR_OFFCHAN] = { .type = NLA_FLAG }, }; /* policy for the key attributes */ @@ -9287,12 +9288,6 @@ static int nl80211_start_radar_detection if (err) return err; - if (netif_carrier_ok(dev)) - return -EBUSY; - - if (wdev->cac_started) - return -EBUSY; - err = cfg80211_chandef_dfs_required(wiphy, &chandef, wdev->iftype); if (err < 0) return err; @@ -9303,6 +9298,16 @@ static int nl80211_start_radar_detection if (!cfg80211_chandef_dfs_usable(wiphy, &chandef)) return -EINVAL; + if (nla_get_flag(info->attrs[NL80211_ATTR_RADAR_OFFCHAN])) + return cfg80211_start_offchan_radar_detection(rdev, wdev, + &chandef); + + if (netif_carrier_ok(dev)) + return -EBUSY; + + if (wdev->cac_started) + return -EBUSY; + /* CAC start is offloaded to HW and can't be started manually */ if (wiphy_ext_feature_isset(wiphy, NL80211_EXT_FEATURE_DFS_OFFLOAD)) return -EOPNOTSUPP; --- a/net/wireless/rdev-ops.h +++ b/net/wireless/rdev-ops.h @@ -1381,4 +1381,21 @@ static inline int rdev_color_change(stru return ret; } +static inline int +rdev_set_radar_offchan(struct cfg80211_registered_device *rdev, + struct cfg80211_chan_def *chandef) +{ + struct wiphy *wiphy = &rdev->wiphy; + int ret; + + if (!rdev->ops->set_radar_offchan) + return -EOPNOTSUPP; + + trace_rdev_set_radar_offchan(wiphy, chandef); + ret = rdev->ops->set_radar_offchan(wiphy, chandef); + trace_rdev_return_int(wiphy, ret); + + return ret; +} + #endif /* __CFG80211_RDEV_OPS */ --- a/net/wireless/trace.h +++ b/net/wireless/trace.h @@ -3643,6 +3643,25 @@ TRACE_EVENT(cfg80211_bss_color_notify, __entry->color_bitmap) ); +TRACE_EVENT(rdev_set_radar_offchan, + TP_PROTO(struct wiphy *wiphy, struct cfg80211_chan_def *chandef), + + TP_ARGS(wiphy, chandef), + + TP_STRUCT__entry( + WIPHY_ENTRY + CHAN_DEF_ENTRY + ), + + TP_fast_assign( + WIPHY_ASSIGN; + CHAN_DEF_ASSIGN(chandef) + ), + + TP_printk(WIPHY_PR_FMT ", " CHAN_DEF_PR_FMT, + WIPHY_PR_ARG, CHAN_DEF_PR_ARG) +); + #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */ #undef TRACE_INCLUDE_PATH