From 5cb1270143668fa72007b52a8be6b4aa2c182809 Mon Sep 17 00:00:00 2001 From: Arik Nemtsov Date: Thu, 22 Jan 2015 12:19:26 +0200 Subject: [PATCH] iwlwifi: mvm: improve TDLS ch-sw state machine Add a response-received state and add more limits on allowed requests in each state of the connection. Previously ch-switch requests from other peers could interrupt an outgoing active ch-switch. Also stale packets from the current peer could disrupt the channel switch state. Signed-off-by: Arik Nemtsov Reviewed-by: Johannes Berg Signed-off-by: Emmanuel Grumbach --- drivers/net/wireless/iwlwifi/mvm/mvm.h | 1 + drivers/net/wireless/iwlwifi/mvm/tdls.c | 48 +++++++++++++++++-------- 2 files changed, 35 insertions(+), 14 deletions(-) diff --git a/drivers/net/wireless/iwlwifi/mvm/mvm.h b/drivers/net/wireless/iwlwifi/mvm/mvm.h index 7773ffc4ca62..fc80b7b43b21 100644 --- a/drivers/net/wireless/iwlwifi/mvm/mvm.h +++ b/drivers/net/wireless/iwlwifi/mvm/mvm.h @@ -532,6 +532,7 @@ enum { enum iwl_mvm_tdls_cs_state { IWL_MVM_TDLS_SW_IDLE = 0, IWL_MVM_TDLS_SW_REQ_SENT, + IWL_MVM_TDLS_SW_RESP_RCVD, IWL_MVM_TDLS_SW_REQ_RCVD, IWL_MVM_TDLS_SW_ACTIVE, }; diff --git a/drivers/net/wireless/iwlwifi/mvm/tdls.c b/drivers/net/wireless/iwlwifi/mvm/tdls.c index c0e00bae5bd0..ea1831ccc8f3 100644 --- a/drivers/net/wireless/iwlwifi/mvm/tdls.c +++ b/drivers/net/wireless/iwlwifi/mvm/tdls.c @@ -228,6 +228,8 @@ iwl_mvm_tdls_cs_state_str(enum iwl_mvm_tdls_cs_state state) return "IDLE"; case IWL_MVM_TDLS_SW_REQ_SENT: return "REQ SENT"; + case IWL_MVM_TDLS_SW_RESP_RCVD: + return "RESP RECEIVED"; case IWL_MVM_TDLS_SW_REQ_RCVD: return "REQ RECEIVED"; case IWL_MVM_TDLS_SW_ACTIVE: @@ -325,17 +327,27 @@ iwl_mvm_tdls_check_action(struct iwl_mvm *mvm, ret = -EINVAL; break; case IWL_MVM_TDLS_SW_REQ_SENT: + /* only allow requests from the same peer */ + if (!same_peer) + ret = -EBUSY; + else if (type == TDLS_SEND_CHAN_SW_RESP_AND_MOVE_CH && + !peer_initiator) + /* + * We received a ch-switch request while an outgoing + * one is pending. Allow it if the peer is the link + * initiator. + */ + ret = -EBUSY; + else if (type == TDLS_SEND_CHAN_SW_REQ) + /* wait for idle before sending another request */ + ret = -EBUSY; + break; + case IWL_MVM_TDLS_SW_RESP_RCVD: /* - * We received a ch-switch request while an outgoing one is - * pending. Allow it to proceed if the other peer is the same - * one we sent to, and we are not the link initiator. + * we are waiting for the FW to give an "active" notification, + * so ignore requests in the meantime */ - if (type == TDLS_SEND_CHAN_SW_RESP_AND_MOVE_CH) { - if (!same_peer) - ret = -EBUSY; - else if (!peer_initiator) /* we are the initiator */ - ret = -EBUSY; - } + ret = -EBUSY; break; case IWL_MVM_TDLS_SW_REQ_RCVD: /* as above, allow the link initiator to proceed */ @@ -349,9 +361,12 @@ iwl_mvm_tdls_check_action(struct iwl_mvm *mvm, } break; case IWL_MVM_TDLS_SW_ACTIVE: - /* we don't allow initiations during active channel switch */ - if (type == TDLS_SEND_CHAN_SW_REQ) - ret = -EINVAL; + /* + * the only valid request when active is a request to return + * to the base channel by the current off-channel peer + */ + if (type != TDLS_MOVE_CH || !same_peer) + ret = -EBUSY; break; } @@ -473,6 +488,8 @@ iwl_mvm_tdls_config_channel_switch(struct iwl_mvm *mvm, type == TDLS_SEND_CHAN_SW_REQ ? IWL_MVM_TDLS_SW_REQ_SENT : IWL_MVM_TDLS_SW_REQ_RCVD); + } else { + iwl_mvm_tdls_update_cs_state(mvm, IWL_MVM_TDLS_SW_RESP_RCVD); } out: @@ -657,12 +674,15 @@ iwl_mvm_tdls_recv_channel_switch(struct ieee80211_hw *hw, struct iwl_mvm *mvm = IWL_MAC80211_GET_MVM(hw); enum iwl_tdls_channel_switch_type type; unsigned int delay; + const char *action_str = + params->action_code == WLAN_TDLS_CHANNEL_SWITCH_REQUEST ? + "REQ" : "RESP"; mutex_lock(&mvm->mutex); IWL_DEBUG_TDLS(mvm, - "Received TDLS ch switch action %d from %pM status %d\n", - params->action_code, params->sta->addr, params->status); + "Received TDLS ch switch action %s from %pM status %d\n", + action_str, params->sta->addr, params->status); /* * we got a non-zero status from a peer we were switching to - move to -- 2.34.1