From 7d352ccf1e9935b5222ca84e8baeb07a0c8f94b9 Mon Sep 17 00:00:00 2001 From: Youghandhar Chintala Date: Tue, 8 Mar 2022 17:23:24 +0530 Subject: [PATCH] mac80211: Add support to trigger sta disconnect on hardware restart Currently in case of target hardware restart, we just reconfig and re-enable the security keys and enable the network queues to start data traffic back from where it was interrupted. Many ath10k wifi chipsets have sequence numbers for the data packets assigned by firmware and the mac sequence number will restart from zero after target hardware restart leading to mismatch in the sequence number expected by the remote peer vs the sequence number of the frame sent by the target firmware. This mismatch in sequence number will cause out-of-order packets on the remote peer and all the frames sent by the device are dropped until we reach the sequence number which was sent before we restarted the target hardware In order to fix this, we trigger a sta disconnect, in case of target hw restart. After this there will be a fresh connection and thereby avoiding the dropping of frames by remote peer. The right fix would be to pull the entire data path into the host which is not feasible or would need lots of complex changes and will still be inefficient. Tested on ath10k using WCN3990, QCA6174 Signed-off-by: Youghandhar Chintala Link: https://lore.kernel.org/r/20220308115325.5246-2-youghand@codeaurora.org Signed-off-by: Johannes Berg --- include/net/mac80211.h | 10 ++++++++++ net/mac80211/ieee80211_i.h | 3 +++ net/mac80211/mlme.c | 12 ++++++++++++ net/mac80211/util.c | 33 ++++++++++++++++++++++++++++++--- 4 files changed, 55 insertions(+), 3 deletions(-) diff --git a/include/net/mac80211.h b/include/net/mac80211.h index f118b8fe667a..b8e8c82b53aa 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -6070,6 +6070,16 @@ void ieee80211_disconnect(struct ieee80211_vif *vif, bool reconnect); */ void ieee80211_resume_disconnect(struct ieee80211_vif *vif); +/** + * ieee80211_hw_restart_disconnect - disconnect from AP after + * hardware restart + * @vif: &struct ieee80211_vif pointer from the add_interface callback. + * + * Instructs mac80211 to disconnect from the AP after + * hardware restart. + */ +void ieee80211_hw_restart_disconnect(struct ieee80211_vif *vif); + /** * ieee80211_cqm_rssi_notify - inform a configured connection quality monitoring * rssi threshold triggered diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 6a2421a066fb..b07ccfc44115 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -767,6 +767,8 @@ struct ieee80211_if_mesh { * back to wireless media and to the local net stack. * @IEEE80211_SDATA_DISCONNECT_RESUME: Disconnect after resume. * @IEEE80211_SDATA_IN_DRIVER: indicates interface was added to driver + * @IEEE80211_SDATA_DISCONNECT_HW_RESTART: Disconnect after hardware restart + * recovery */ enum ieee80211_sub_if_data_flags { IEEE80211_SDATA_ALLMULTI = BIT(0), @@ -774,6 +776,7 @@ enum ieee80211_sub_if_data_flags { IEEE80211_SDATA_DONT_BRIDGE_PACKETS = BIT(3), IEEE80211_SDATA_DISCONNECT_RESUME = BIT(4), IEEE80211_SDATA_IN_DRIVER = BIT(5), + IEEE80211_SDATA_DISCONNECT_HW_RESTART = BIT(6), }; /** diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 197cad4a2768..29bfce6b3561 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -4934,6 +4934,18 @@ void ieee80211_sta_restart(struct ieee80211_sub_if_data *sdata) sdata_unlock(sdata); return; } + + if (sdata->flags & IEEE80211_SDATA_DISCONNECT_HW_RESTART) { + sdata->flags &= ~IEEE80211_SDATA_DISCONNECT_HW_RESTART; + mlme_dbg(sdata, "driver requested disconnect after hardware restart\n"); + ieee80211_sta_connection_lost(sdata, + ifmgd->associated->bssid, + WLAN_REASON_UNSPECIFIED, + true); + sdata_unlock(sdata); + return; + } + sdata_unlock(sdata); } #endif diff --git a/net/mac80211/util.c b/net/mac80211/util.c index caea8dbd1d9b..682a164f795a 100644 --- a/net/mac80211/util.c +++ b/net/mac80211/util.c @@ -2347,6 +2347,7 @@ int ieee80211_reconfig(struct ieee80211_local *local) struct cfg80211_sched_scan_request *sched_scan_req; bool sched_scan_stopped = false; bool suspended = local->suspended; + bool in_reconfig = false; /* nothing to do if HW shouldn't run */ if (!local->open_count) @@ -2698,6 +2699,7 @@ int ieee80211_reconfig(struct ieee80211_local *local) drv_reconfig_complete(local, IEEE80211_RECONFIG_TYPE_RESTART); if (local->in_reconfig) { + in_reconfig = local->in_reconfig; local->in_reconfig = false; barrier(); @@ -2715,6 +2717,15 @@ int ieee80211_reconfig(struct ieee80211_local *local) IEEE80211_QUEUE_STOP_REASON_SUSPEND, false); + if (in_reconfig) { + list_for_each_entry(sdata, &local->interfaces, list) { + if (!ieee80211_sdata_running(sdata)) + continue; + if (sdata->vif.type == NL80211_IFTYPE_STATION) + ieee80211_sta_restart(sdata); + } + } + if (!suspended) return 0; @@ -2744,7 +2755,7 @@ int ieee80211_reconfig(struct ieee80211_local *local) return 0; } -void ieee80211_resume_disconnect(struct ieee80211_vif *vif) +static void ieee80211_reconfig_disconnect(struct ieee80211_vif *vif, u8 flag) { struct ieee80211_sub_if_data *sdata; struct ieee80211_local *local; @@ -2756,19 +2767,35 @@ void ieee80211_resume_disconnect(struct ieee80211_vif *vif) sdata = vif_to_sdata(vif); local = sdata->local; - if (WARN_ON(!local->resuming)) + if (WARN_ON(flag & IEEE80211_SDATA_DISCONNECT_RESUME && + !local->resuming)) + return; + + if (WARN_ON(flag & IEEE80211_SDATA_DISCONNECT_HW_RESTART && + !local->in_reconfig)) return; if (WARN_ON(vif->type != NL80211_IFTYPE_STATION)) return; - sdata->flags |= IEEE80211_SDATA_DISCONNECT_RESUME; + sdata->flags |= flag; mutex_lock(&local->key_mtx); list_for_each_entry(key, &sdata->key_list, list) key->flags |= KEY_FLAG_TAINTED; mutex_unlock(&local->key_mtx); } + +void ieee80211_hw_restart_disconnect(struct ieee80211_vif *vif) +{ + ieee80211_reconfig_disconnect(vif, IEEE80211_SDATA_DISCONNECT_HW_RESTART); +} +EXPORT_SYMBOL_GPL(ieee80211_hw_restart_disconnect); + +void ieee80211_resume_disconnect(struct ieee80211_vif *vif) +{ + ieee80211_reconfig_disconnect(vif, IEEE80211_SDATA_DISCONNECT_RESUME); +} EXPORT_SYMBOL_GPL(ieee80211_resume_disconnect); void ieee80211_recalc_smps(struct ieee80211_sub_if_data *sdata)