From: Hari Chandrakanthan When any incumbent signal is detected by an AP/mesh interface operating in 6 GHz band, FCC mandates the AP/mesh to vacate the channels affected by it [1]. Add a new API cfg80211_incumbent_signal_detect_event() that can be used by mac80211 (or full mac drivers) to notify the higher layers about the signal interference event with the interference bitmap in which each bit denotes the affected 20 MHz in the operating channel. Add support for the new nl80211 event and nl80211 attribute as well to notify userspace on the details about the interference event. Userspace is expected to process it and take further action - vacate the channel, or reduce the bandwidth. [1] - https://apps.fcc.gov/kdb/GetAttachment.html?id=nXQiRC%2B4mfiA54Zha%2BrW4Q%3D%3D&desc=987594%20D02%20U-NII%206%20GHz%20EMC%20Measurement%20v03&tracking_number=277034 Signed-off-by: Hari Chandrakanthan Signed-off-by: Amith A --- include/net/cfg80211.h | 19 ++++++++++++++++++ include/uapi/linux/nl80211.h | 19 ++++++++++++++++++ net/wireless/nl80211.c | 39 ++++++++++++++++++++++++++++++++++++ net/wireless/trace.h | 19 ++++++++++++++++++ 4 files changed, 96 insertions(+) diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index 4072a67c9cc9..821f96353189 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -10052,4 +10052,23 @@ ssize_t wiphy_locked_debugfs_write(struct wiphy *wiphy, struct file *file, void *data); #endif + +/** + * cfg80211_incumbent_signal_notify - Notify userspace of incumbent signal detection + * @wiphy: the wiphy to use + * @chandef: channel definition in which the interference was detected + * @signal_interference_bitmap: bitmap indicating interference across 20 MHz segments + * + * Use this function to notify userspace when an incumbent signal is detected on + * the operating channel in the 6 GHz band. The notification includes the + * current channel definition and a bitmap representing interference across + * the operating bandwidth. Each bit in the bitmap corresponds to a 20 MHz + * segment, with the lowest bit representing the lowest frequency segment. + * Punctured sub-channels are included in the bitmap structure but are always + * set to zero since interference detection is not performed on them. + */ +void cfg80211_incumbent_signal_notify(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + u32 signal_interference_bitmap); + #endif /* __NET_CFG80211_H */ diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index aed0b4c5d5e8..5970357eae32 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -1344,6 +1344,12 @@ * control EPCS configuration. Used to notify userland on the current state * of EPCS. * + * @NL80211_CMD_INCUMBENT_SIGNAL_DETECT: Once any incumbent signal is detected + * on the operating channel in 6 GHz band, userspace is notified with the + * signal interference bitmap using + * %NL80211_ATTR_INCUMBENT_SIGNAL_INTERFERENCE_BITMAP. The current channel + * definition is also sent. + * * @NL80211_CMD_MAX: highest used command number * @__NL80211_CMD_AFTER_LAST: internal use */ @@ -1604,6 +1610,8 @@ enum nl80211_commands { NL80211_CMD_ASSOC_MLO_RECONF, NL80211_CMD_EPCS_CFG, + NL80211_CMD_INCUMBENT_SIGNAL_DETECT, + /* add new commands above here */ /* used to define NL80211_CMD_MAX below */ @@ -2936,6 +2944,15 @@ enum nl80211_commands { * indicate that it wants strict checking on the BSS parameters to be * modified. * + * @NL80211_ATTR_INCUMBENT_SIGNAL_INTERFERENCE_BITMAP: u32 attribute specifying + * the signal interference bitmap detected on the operating bandwidth for + * %NL80211_CMD_INCUMBENT_SIGNAL_DETECT. Each bit represents a 20 MHz + * segment, lowest bit corresponds to the lowest 20 MHz segment, in the + * operating bandwidth where the interference is detected. Punctured + * sub-channels are included in the bitmap structure; however, since + * interference detection is not performed on these sub-channels, their + * corresponding bits are consistently set to zero. + * * @NUM_NL80211_ATTR: total number of nl80211_attrs available * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use @@ -3499,6 +3516,8 @@ enum nl80211_attrs { NL80211_ATTR_S1G_SHORT_BEACON, NL80211_ATTR_BSS_PARAM, + NL80211_ATTR_INCUMBENT_SIGNAL_INTERFERENCE_BITMAP, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index 99e2aadc65f7..1cd93292cf17 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -20714,6 +20714,45 @@ void cfg80211_ch_switch_notify(struct net_device *dev, } EXPORT_SYMBOL(cfg80211_ch_switch_notify); +void cfg80211_incumbent_signal_notify(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + u32 signal_interference_bitmap) +{ + struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy); + struct sk_buff *msg; + void *hdr; + + trace_cfg80211_incumbent_signal_notify(wiphy, chandef, signal_interference_bitmap); + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return; + + hdr = nl80211hdr_put(msg, 0, 0, 0, NL80211_CMD_INCUMBENT_SIGNAL_DETECT); + if (!hdr) + goto nla_put_failure; + + if (nla_put_u32(msg, NL80211_ATTR_WIPHY, rdev->wiphy_idx)) + goto nla_put_failure; + + if (nl80211_send_chandef(msg, chandef)) + goto nla_put_failure; + + if (nla_put_u32(msg, NL80211_ATTR_INCUMBENT_SIGNAL_INTERFERENCE_BITMAP, + signal_interference_bitmap)) + goto nla_put_failure; + + genlmsg_end(msg, hdr); + + genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0, + NL80211_MCGRP_MLME, GFP_KERNEL); + return; + +nla_put_failure: + nlmsg_free(msg); +} +EXPORT_SYMBOL(cfg80211_incumbent_signal_notify); + void cfg80211_ch_switch_started_notify(struct net_device *dev, struct cfg80211_chan_def *chandef, unsigned int link_id, u8 count, diff --git a/net/wireless/trace.h b/net/wireless/trace.h index 9b6074155d59..eaf1a489e9c4 100644 --- a/net/wireless/trace.h +++ b/net/wireless/trace.h @@ -4166,6 +4166,25 @@ TRACE_EVENT(cfg80211_epcs_changed, WDEV_PR_ARG, __entry->enabled) ); +TRACE_EVENT(cfg80211_incumbent_signal_notify, + TP_PROTO(struct wiphy *wiphy, + struct cfg80211_chan_def *chandef, + u32 signal_interference_bitmap), + TP_ARGS(wiphy, chandef, signal_interference_bitmap), + TP_STRUCT__entry( + WIPHY_ENTRY + CHAN_DEF_ENTRY + __field(u32, signal_interference_bitmap) + ), + TP_fast_assign( + WIPHY_ASSIGN; + CHAN_DEF_ASSIGN(chandef); + __entry->signal_interference_bitmap = signal_interference_bitmap; + ), + TP_printk(WIPHY_PR_FMT ", " CHAN_DEF_PR_FMT ", signal_interference_bitmap=0x%x", + WIPHY_PR_ARG, CHAN_DEF_PR_ARG, __entry->signal_interference_bitmap) +); + #endif /* !__RDEV_OPS_TRACE || TRACE_HEADER_MULTI_READ */ #undef TRACE_INCLUDE_PATH -- 2.34.1