/****************************************************************************** * * Copyright 1999-2012 Broadcom Corporation * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * ******************************************************************************/ /****************************************************************************** * * this file contains the functions relating to link management. A "link" * is a connection between this device and another device. Only ACL links * are managed. * ******************************************************************************/ #define LOG_TAG "l2c_link" #include #include "device/include/controller.h" #include "main/shim/l2c_api.h" #include "main/shim/shim.h" #include "osi/include/log.h" #include "osi/include/osi.h" #include "stack/btm/btm_int_types.h" #include "stack/include/acl_api.h" #include "stack/include/bt_types.h" #include "stack/include/hci_error_code.h" #include "stack/include/hcimsgs.h" #include "stack/l2cap/l2c_int.h" #include "types/bt_transport.h" #include "types/raw_address.h" extern tBTM_CB btm_cb; bool BTM_ReadPowerMode(const RawAddress& remote_bda, tBTM_PM_MODE* p_mode); bool btm_dev_support_role_switch(const RawAddress& bd_addr); tBTM_STATUS btm_sec_disconnect(uint16_t handle, tHCI_STATUS reason); void btm_acl_created(const RawAddress& bda, uint16_t hci_handle, uint8_t link_role, tBT_TRANSPORT transport); void btm_acl_removed(uint16_t handle); void btm_acl_set_paging(bool value); void btm_ble_decrement_link_topology_mask(uint8_t link_role); void btm_sco_acl_removed(const RawAddress* bda); static void l2c_link_send_to_lower(tL2C_LCB* p_lcb, BT_HDR* p_buf); static BT_HDR* l2cu_get_next_buffer_to_send(tL2C_LCB* p_lcb); /******************************************************************************* * * Function l2c_link_hci_conn_req * * Description This function is called when an HCI Connection Request * event is received. * ******************************************************************************/ void l2c_link_hci_conn_req(const RawAddress& bd_addr) { tL2C_LCB* p_lcb; tL2C_LCB* p_lcb_cur; int xx; bool no_links; /* See if we have a link control block for the remote device */ p_lcb = l2cu_find_lcb_by_bd_addr(bd_addr, BT_TRANSPORT_BR_EDR); /* If we don't have one, create one and accept the connection. */ if (!p_lcb) { p_lcb = l2cu_allocate_lcb(bd_addr, false, BT_TRANSPORT_BR_EDR); if (!p_lcb) { btsnd_hcic_reject_conn(bd_addr, HCI_ERR_HOST_REJECT_RESOURCES); LOG_ERROR("L2CAP failed to allocate LCB"); return; } no_links = true; /* If we already have connection, accept as a central */ for (xx = 0, p_lcb_cur = &l2cb.lcb_pool[0]; xx < MAX_L2CAP_LINKS; xx++, p_lcb_cur++) { if (p_lcb_cur == p_lcb) continue; if (p_lcb_cur->in_use) { no_links = false; p_lcb->SetLinkRoleAsCentral(); break; } } if (no_links) { if (!btm_dev_support_role_switch(bd_addr)) p_lcb->SetLinkRoleAsPeripheral(); else p_lcb->SetLinkRoleAsCentral(); } /* Tell the other side we accept the connection */ acl_accept_connection_request(bd_addr, p_lcb->LinkRole()); p_lcb->link_state = LST_CONNECTING; /* Start a timer waiting for connect complete */ alarm_set_on_mloop(p_lcb->l2c_lcb_timer, L2CAP_LINK_CONNECT_TIMEOUT_MS, l2c_lcb_timer_timeout, p_lcb); return; } /* We already had a link control block. Check what state it is in */ if ((p_lcb->link_state == LST_CONNECTING) || (p_lcb->link_state == LST_CONNECT_HOLDING)) { if (!btm_dev_support_role_switch(bd_addr)) p_lcb->SetLinkRoleAsPeripheral(); else p_lcb->SetLinkRoleAsCentral(); acl_accept_connection_request(bd_addr, p_lcb->LinkRole()); p_lcb->link_state = LST_CONNECTING; } else if (p_lcb->link_state == LST_DISCONNECTING) { acl_reject_connection_request(bd_addr, HCI_ERR_HOST_REJECT_DEVICE); } else { LOG_ERROR("L2CAP got conn_req while connected (state:%d). Reject it", p_lcb->link_state); acl_reject_connection_request(bd_addr, HCI_ERR_CONNECTION_EXISTS); } } void l2c_link_hci_conn_comp(tHCI_STATUS status, uint16_t handle, const RawAddress& p_bda) { if (bluetooth::shim::is_gd_l2cap_enabled()) { return; } tL2C_CONN_INFO ci; tL2C_LCB* p_lcb; tL2C_CCB* p_ccb; /* Save the parameters */ ci.status = status; ci.bd_addr = p_bda; /* See if we have a link control block for the remote device */ p_lcb = l2cu_find_lcb_by_bd_addr(ci.bd_addr, BT_TRANSPORT_BR_EDR); /* If we don't have one, allocate one */ if (p_lcb == nullptr) { p_lcb = l2cu_allocate_lcb(ci.bd_addr, false, BT_TRANSPORT_BR_EDR); if (p_lcb == nullptr) { LOG_WARN("Failed to allocate an LCB"); return; } LOG_DEBUG("Allocated l2cap control block for new connection state:%s", link_state_text(p_lcb->link_state).c_str()); p_lcb->link_state = LST_CONNECTING; } if ((p_lcb->link_state == LST_CONNECTED) && (status == HCI_ERR_CONNECTION_EXISTS)) { LOG_WARN("Connection already exists handle:0x%04x", handle); return; } else if (p_lcb->link_state != LST_CONNECTING) { LOG_ERROR( "Link received unexpected connection complete state:%s status:%s " "handle:0x%04x", link_state_text(p_lcb->link_state).c_str(), hci_error_code_text(status).c_str(), p_lcb->Handle()); if (status != HCI_SUCCESS) { LOG_ERROR("Disconnecting..."); l2c_link_hci_disc_comp(p_lcb->Handle(), status); } return; } /* Save the handle */ l2cu_set_lcb_handle(*p_lcb, handle); if (ci.status == HCI_SUCCESS) { /* Connected OK. Change state to connected */ p_lcb->link_state = LST_CONNECTED; /* Get the peer information if the l2cap flow-control/rtrans is supported */ l2cu_send_peer_info_req(p_lcb, L2CAP_EXTENDED_FEATURES_INFO_TYPE); if (p_lcb->IsBonding()) { LOG_DEBUG("Link is dedicated bonding handle:0x%04x", p_lcb->Handle()); if (l2cu_start_post_bond_timer(handle)) return; } /* Update the timeouts in the hold queue */ l2c_process_held_packets(false); alarm_cancel(p_lcb->l2c_lcb_timer); /* For all channels, send the event through their FSMs */ for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb; p_ccb = p_ccb->p_next_ccb) { l2c_csm_execute(p_ccb, L2CEVT_LP_CONNECT_CFM, &ci); } if (!p_lcb->ccb_queue.p_first_ccb) { uint64_t timeout_ms = L2CAP_LINK_STARTUP_TOUT * 1000; alarm_set_on_mloop(p_lcb->l2c_lcb_timer, timeout_ms, l2c_lcb_timer_timeout, p_lcb); } } /* Max number of acl connections. */ /* If there's an lcb disconnecting set this one to holding */ else if ((ci.status == HCI_ERR_MAX_NUM_OF_CONNECTIONS) && l2cu_lcb_disconnecting()) { LOG_WARN("Delaying connection as reached max number of links:%u", HCI_ERR_MAX_NUM_OF_CONNECTIONS); p_lcb->link_state = LST_CONNECT_HOLDING; p_lcb->InvalidateHandle(); } else { /* Just in case app decides to try again in the callback context */ p_lcb->link_state = LST_DISCONNECTING; /* Connection failed. For all channels, send the event through */ /* their FSMs. The CCBs should remove themselves from the LCB */ for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb;) { tL2C_CCB* pn = p_ccb->p_next_ccb; l2c_csm_execute(p_ccb, L2CEVT_LP_CONNECT_CFM_NEG, &ci); p_ccb = pn; } LOG_INFO("Disconnecting link handle:0x%04x status:%s", p_lcb->Handle(), hci_error_code_text(status).c_str()); p_lcb->SetDisconnectReason(status); /* Release the LCB */ if (p_lcb->ccb_queue.p_first_ccb == NULL) l2cu_release_lcb(p_lcb); else /* there are any CCBs remaining */ { if (ci.status == HCI_ERR_CONNECTION_EXISTS) { /* we are in collision situation, wait for connecttion request from * controller */ p_lcb->link_state = LST_CONNECTING; } else { l2cu_create_conn_br_edr(p_lcb); } } } } /******************************************************************************* * * Function l2c_link_sec_comp * * Description This function is called when required security procedures * are completed. * * Returns void * ******************************************************************************/ void l2c_link_sec_comp(const RawAddress* p_bda, UNUSED_ATTR tBT_TRANSPORT transport, void* p_ref_data, tBTM_STATUS status) { l2c_link_sec_comp2(*p_bda, transport, p_ref_data, status); } void l2c_link_sec_comp2(const RawAddress& p_bda, UNUSED_ATTR tBT_TRANSPORT transport, void* p_ref_data, tBTM_STATUS status) { tL2C_CONN_INFO ci; tL2C_LCB* p_lcb; tL2C_CCB* p_ccb; tL2C_CCB* p_next_ccb; LOG_DEBUG("btm_status=%s, BD_ADDR=%s, transport=%s", btm_status_text(status).c_str(), PRIVATE_ADDRESS(p_bda), bt_transport_text(transport).c_str()); if (status == BTM_SUCCESS_NO_SECURITY) { status = BTM_SUCCESS; } /* Save the parameters */ ci.status = status; ci.bd_addr = p_bda; p_lcb = l2cu_find_lcb_by_bd_addr(p_bda, transport); /* If we don't have one, this is an error */ if (!p_lcb) { LOG_WARN("L2CAP got sec_comp for unknown BD_ADDR"); return; } /* Match p_ccb with p_ref_data returned by sec manager */ for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb; p_ccb = p_next_ccb) { p_next_ccb = p_ccb->p_next_ccb; if (p_ccb == p_ref_data) { switch (status) { case BTM_SUCCESS: l2c_csm_execute(p_ccb, L2CEVT_SEC_COMP, &ci); break; case BTM_DELAY_CHECK: /* start a timer - encryption change not received before L2CAP connect * req */ alarm_set_on_mloop(p_ccb->l2c_ccb_timer, L2CAP_DELAY_CHECK_SM4_TIMEOUT_MS, l2c_ccb_timer_timeout, p_ccb); return; default: l2c_csm_execute(p_ccb, L2CEVT_SEC_COMP_NEG, &ci); break; } break; } } } /******************************************************************************* * * Function l2c_link_hci_disc_comp * * Description This function is called when an HCI Disconnect Complete * event is received. * * Returns true if the link is known about, else false * ******************************************************************************/ bool l2c_link_hci_disc_comp(uint16_t handle, tHCI_REASON reason) { if (bluetooth::shim::is_gd_l2cap_enabled()) { return false; } tL2C_LCB* p_lcb = l2cu_find_lcb_by_handle(handle); tL2C_CCB* p_ccb; bool status = true; bool lcb_is_free = true; /* If we don't have one, maybe an SCO link. Send to MM */ if (!p_lcb) { status = false; } else { p_lcb->SetDisconnectReason(reason); /* Just in case app decides to try again in the callback context */ p_lcb->link_state = LST_DISCONNECTING; /* Check for BLE and handle that differently */ if (p_lcb->transport == BT_TRANSPORT_LE) btm_ble_decrement_link_topology_mask(p_lcb->LinkRole()); /* Link is disconnected. For all channels, send the event through */ /* their FSMs. The CCBs should remove themselves from the LCB */ for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb;) { tL2C_CCB* pn = p_ccb->p_next_ccb; /* Keep connect pending control block (if exists) * Possible Race condition when a reconnect occurs * on the channel during a disconnect of link. This * ccb will be automatically retried after link disconnect * arrives */ if (p_ccb != p_lcb->p_pending_ccb) { l2c_csm_execute(p_ccb, L2CEVT_LP_DISCONNECT_IND, &reason); } p_ccb = pn; } if (p_lcb->transport == BT_TRANSPORT_BR_EDR) /* Tell SCO management to drop any SCOs on this ACL */ btm_sco_acl_removed(&p_lcb->remote_bd_addr); /* If waiting for disconnect and reconnect is pending start the reconnect now race condition where layer above issued connect request on link that was disconnecting */ if (p_lcb->ccb_queue.p_first_ccb != NULL || p_lcb->p_pending_ccb) { LOG_DEBUG("l2c_link_hci_disc_comp: Restarting pending ACL request"); /* Release any held buffers */ while (!list_is_empty(p_lcb->link_xmit_data_q)) { BT_HDR* p_buf = static_cast(list_front(p_lcb->link_xmit_data_q)); list_remove(p_lcb->link_xmit_data_q, p_buf); osi_free(p_buf); } /* for LE link, always drop and re-open to ensure to get LE remote feature */ if (p_lcb->transport == BT_TRANSPORT_LE) { btm_acl_removed(handle); } else { /* If we are going to re-use the LCB without dropping it, release all fixed channels here */ int xx; for (xx = 0; xx < L2CAP_NUM_FIXED_CHNLS; xx++) { if (p_lcb->p_fixed_ccbs[xx] && p_lcb->p_fixed_ccbs[xx] != p_lcb->p_pending_ccb) { (*l2cb.fixed_reg[xx].pL2CA_FixedConn_Cb)( xx + L2CAP_FIRST_FIXED_CHNL, p_lcb->remote_bd_addr, false, p_lcb->DisconnectReason(), p_lcb->transport); if (p_lcb->p_fixed_ccbs[xx] == NULL) { LOG_ERROR( "unexpected p_fixed_ccbs[%d] is NULL remote_bd_addr = %s " "p_lcb = %p in_use = %d link_state = %d handle = %d " "link_role = %d is_bonding = %d disc_reason = %d transport = " "%d", xx, p_lcb->remote_bd_addr.ToString().c_str(), p_lcb, p_lcb->in_use, p_lcb->link_state, p_lcb->Handle(), p_lcb->LinkRole(), p_lcb->IsBonding(), p_lcb->DisconnectReason(), p_lcb->transport); } CHECK(p_lcb->p_fixed_ccbs[xx] != NULL); l2cu_release_ccb(p_lcb->p_fixed_ccbs[xx]); p_lcb->p_fixed_ccbs[xx] = NULL; } } } if (p_lcb->transport == BT_TRANSPORT_LE) { if (l2cu_create_conn_le(p_lcb)) lcb_is_free = false; /* still using this lcb */ } else { l2cu_create_conn_br_edr(p_lcb); lcb_is_free = false; /* still using this lcb */ } } p_lcb->p_pending_ccb = NULL; /* Release the LCB */ if (lcb_is_free) l2cu_release_lcb(p_lcb); } /* Now that we have a free acl connection, see if any lcbs are pending */ if (lcb_is_free && ((p_lcb = l2cu_find_lcb_by_state(LST_CONNECT_HOLDING)) != NULL)) { /* we found one-- create a connection */ l2cu_create_conn_br_edr(p_lcb); } return status; } /******************************************************************************* * * Function l2c_link_timeout * * Description This function is called when a link timer expires * * Returns void * ******************************************************************************/ void l2c_link_timeout(tL2C_LCB* p_lcb) { tL2C_CCB* p_ccb; tBTM_STATUS rc; LOG_DEBUG("L2CAP - l2c_link_timeout() link state:%s is_bonding:%s", link_state_text(p_lcb->link_state).c_str(), logbool(p_lcb->IsBonding()).c_str()); /* If link was connecting or disconnecting, clear all channels and drop the * LCB */ if ((p_lcb->link_state == LST_CONNECTING_WAIT_SWITCH) || (p_lcb->link_state == LST_CONNECTING) || (p_lcb->link_state == LST_CONNECT_HOLDING) || (p_lcb->link_state == LST_DISCONNECTING)) { p_lcb->p_pending_ccb = NULL; /* For all channels, send a disconnect indication event through */ /* their FSMs. The CCBs should remove themselves from the LCB */ for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb;) { tL2C_CCB* pn = p_ccb->p_next_ccb; l2c_csm_execute(p_ccb, L2CEVT_LP_DISCONNECT_IND, NULL); p_ccb = pn; } /* Release the LCB */ l2cu_release_lcb(p_lcb); } /* If link is connected, check for inactivity timeout */ if (p_lcb->link_state == LST_CONNECTED) { /* If no channels in use, drop the link. */ if (!p_lcb->ccb_queue.p_first_ccb) { uint64_t timeout_ms; bool start_timeout = true; LOG_WARN("TODO: Remove this callback into bcm_sec_disconnect"); rc = btm_sec_disconnect(p_lcb->Handle(), HCI_ERR_PEER_USER); if (rc == BTM_CMD_STORED) { /* Security Manager will take care of disconnecting, state will be * updated at that time */ start_timeout = false; } else if (rc == BTM_CMD_STARTED) { p_lcb->link_state = LST_DISCONNECTING; timeout_ms = L2CAP_LINK_DISCONNECT_TIMEOUT_MS; } else if (rc == BTM_SUCCESS) { l2cu_process_fixed_disc_cback(p_lcb); /* BTM SEC will make sure that link is release (probably after pairing * is done) */ p_lcb->link_state = LST_DISCONNECTING; start_timeout = false; } else if (rc == BTM_BUSY) { /* BTM is still executing security process. Let lcb stay as connected */ start_timeout = false; } else if (p_lcb->IsBonding()) { acl_disconnect_from_handle(p_lcb->Handle(), HCI_ERR_PEER_USER); l2cu_process_fixed_disc_cback(p_lcb); p_lcb->link_state = LST_DISCONNECTING; timeout_ms = L2CAP_LINK_DISCONNECT_TIMEOUT_MS; } else { /* probably no buffer to send disconnect */ timeout_ms = BT_1SEC_TIMEOUT_MS; } if (start_timeout) { alarm_set_on_mloop(p_lcb->l2c_lcb_timer, timeout_ms, l2c_lcb_timer_timeout, p_lcb); } } else { /* Check in case we were flow controlled */ l2c_link_check_send_pkts(p_lcb, 0, NULL); } } } /******************************************************************************* * * Function l2c_info_resp_timer_timeout * * Description This function is called when an info request times out * * Returns void * ******************************************************************************/ void l2c_info_resp_timer_timeout(void* data) { tL2C_LCB* p_lcb = (tL2C_LCB*)data; tL2C_CCB* p_ccb; tL2C_CONN_INFO ci; /* If we timed out waiting for info response, just continue using basic if * allowed */ if (p_lcb->w4_info_rsp) { /* If waiting for security complete, restart the info response timer */ for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb; p_ccb = p_ccb->p_next_ccb) { if ((p_ccb->chnl_state == CST_ORIG_W4_SEC_COMP) || (p_ccb->chnl_state == CST_TERM_W4_SEC_COMP)) { alarm_set_on_mloop(p_lcb->info_resp_timer, L2CAP_WAIT_INFO_RSP_TIMEOUT_MS, l2c_info_resp_timer_timeout, p_lcb); return; } } p_lcb->w4_info_rsp = false; /* If link is in process of being brought up */ if ((p_lcb->link_state != LST_DISCONNECTED) && (p_lcb->link_state != LST_DISCONNECTING)) { /* Notify active channels that peer info is finished */ if (p_lcb->ccb_queue.p_first_ccb) { ci.status = HCI_SUCCESS; ci.bd_addr = p_lcb->remote_bd_addr; for (p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb; p_ccb = p_ccb->p_next_ccb) { l2c_csm_execute(p_ccb, L2CEVT_L2CAP_INFO_RSP, &ci); } } } } } /******************************************************************************* * * Function l2c_link_adjust_allocation * * Description This function is called when a link is created or removed * to calculate the amount of packets each link may send to * the HCI without an ack coming back. * * Currently, this is a simple allocation, dividing the * number of Controller Packets by the number of links. In * the future, QOS configuration should be examined. * * Returns void * ******************************************************************************/ void l2c_link_adjust_allocation(void) { uint16_t qq, yy, qq_remainder; tL2C_LCB* p_lcb; uint16_t hi_quota, low_quota; uint16_t num_lowpri_links = 0; uint16_t num_hipri_links = 0; uint16_t controller_xmit_quota = l2cb.num_lm_acl_bufs; uint16_t high_pri_link_quota = L2CAP_HIGH_PRI_MIN_XMIT_QUOTA_A; bool is_share_buffer = (l2cb.num_lm_ble_bufs == L2C_DEF_NUM_BLE_BUF_SHARED) ? true : false; /* If no links active, reset buffer quotas and controller buffers */ if (l2cb.num_used_lcbs == 0) { l2cb.controller_xmit_window = l2cb.num_lm_acl_bufs; l2cb.round_robin_quota = l2cb.round_robin_unacked = 0; return; } /* First, count the links */ for (yy = 0, p_lcb = &l2cb.lcb_pool[0]; yy < MAX_L2CAP_LINKS; yy++, p_lcb++) { if (p_lcb->in_use && (is_share_buffer || p_lcb->transport != BT_TRANSPORT_LE)) { if (p_lcb->acl_priority == L2CAP_PRIORITY_HIGH) num_hipri_links++; else num_lowpri_links++; } } /* now adjust high priority link quota */ low_quota = num_lowpri_links ? 1 : 0; while ((num_hipri_links * high_pri_link_quota + low_quota) > controller_xmit_quota) high_pri_link_quota--; /* Work out the xmit quota and buffer quota high and low priorities */ hi_quota = num_hipri_links * high_pri_link_quota; low_quota = (hi_quota < controller_xmit_quota) ? controller_xmit_quota - hi_quota : 1; /* Work out and save the HCI xmit quota for each low priority link */ /* If each low priority link cannot have at least one buffer */ if (num_lowpri_links > low_quota) { l2cb.round_robin_quota = low_quota; qq = qq_remainder = 1; } /* If each low priority link can have at least one buffer */ else if (num_lowpri_links > 0) { l2cb.round_robin_quota = 0; l2cb.round_robin_unacked = 0; qq = low_quota / num_lowpri_links; qq_remainder = low_quota % num_lowpri_links; } /* If no low priority link */ else { l2cb.round_robin_quota = 0; l2cb.round_robin_unacked = 0; qq = qq_remainder = 1; } LOG_DEBUG( "l2c_link_adjust_allocation num_hipri: %u num_lowpri: %u low_quota: " "%u round_robin_quota: %u qq: %u", num_hipri_links, num_lowpri_links, low_quota, l2cb.round_robin_quota, qq); /* Now, assign the quotas to each link */ for (yy = 0, p_lcb = &l2cb.lcb_pool[0]; yy < MAX_L2CAP_LINKS; yy++, p_lcb++) { if (p_lcb->in_use && (is_share_buffer || p_lcb->transport != BT_TRANSPORT_LE)) { if (p_lcb->acl_priority == L2CAP_PRIORITY_HIGH) { p_lcb->link_xmit_quota = high_pri_link_quota; } else { /* Safety check in case we switched to round-robin with something * outstanding */ /* if sent_not_acked is added into round_robin_unacked then don't add it * again */ /* l2cap keeps updating sent_not_acked for exiting from round robin */ if ((p_lcb->link_xmit_quota > 0) && (qq == 0)) l2cb.round_robin_unacked += p_lcb->sent_not_acked; p_lcb->link_xmit_quota = qq; if (qq_remainder > 0) { p_lcb->link_xmit_quota++; qq_remainder--; } } LOG_DEBUG( "l2c_link_adjust_allocation LCB %d Priority: %d XmitQuota: %d", yy, p_lcb->acl_priority, p_lcb->link_xmit_quota); LOG_DEBUG(" SentNotAcked: %d RRUnacked: %d", p_lcb->sent_not_acked, l2cb.round_robin_unacked); /* There is a special case where we have readjusted the link quotas and */ /* this link may have sent anything but some other link sent packets so */ /* so we may need a timer to kick off this link's transmissions. */ if ((p_lcb->link_state == LST_CONNECTED) && (!list_is_empty(p_lcb->link_xmit_data_q)) && (p_lcb->sent_not_acked < p_lcb->link_xmit_quota)) { alarm_set_on_mloop(p_lcb->l2c_lcb_timer, L2CAP_LINK_FLOW_CONTROL_TIMEOUT_MS, l2c_lcb_timer_timeout, p_lcb); } } } } /******************************************************************************* * * Function l2c_link_adjust_chnl_allocation * * Description This function is called to calculate the amount of packets * each non-F&EC channel may have outstanding. * * Currently, this is a simple allocation, dividing the number * of packets allocated to the link by the number of channels. * In the future, QOS configuration should be examined. * * Returns void * ******************************************************************************/ void l2c_link_adjust_chnl_allocation(void) { /* assign buffer quota to each channel based on its data rate requirement */ for (uint8_t xx = 0; xx < MAX_L2CAP_CHANNELS; xx++) { tL2C_CCB* p_ccb = l2cb.ccb_pool + xx; if (!p_ccb->in_use) continue; tL2CAP_CHNL_DATA_RATE data_rate = p_ccb->tx_data_rate + p_ccb->rx_data_rate; p_ccb->buff_quota = L2CAP_CBB_DEFAULT_DATA_RATE_BUFF_QUOTA * data_rate; LOG_DEBUG( "CID:0x%04x FCR Mode:%u Priority:%u TxDataRate:%u RxDataRate:%u " "Quota:%u", p_ccb->local_cid, p_ccb->peer_cfg.fcr.mode, p_ccb->ccb_priority, p_ccb->tx_data_rate, p_ccb->rx_data_rate, p_ccb->buff_quota); /* quota may be change so check congestion */ l2cu_check_channel_congestion(p_ccb); } } void l2c_link_init() { if (bluetooth::shim::is_gd_l2cap_enabled()) { // GD L2cap gets this info through GD ACL return; } const controller_t* controller = controller_get_interface(); l2cb.num_lm_acl_bufs = controller->get_acl_buffer_count_classic(); l2cb.controller_xmit_window = controller->get_acl_buffer_count_classic(); } /******************************************************************************* * * Function l2c_link_role_changed * * Description This function is called whan a link's central/peripheral *role change event is received. It simply updates the link control block. * * Returns void * ******************************************************************************/ void l2c_link_role_changed(const RawAddress* bd_addr, uint8_t new_role, uint8_t hci_status) { /* Make sure not called from HCI Command Status (bd_addr and new_role are * invalid) */ if (bd_addr != nullptr) { /* If here came form hci role change event */ tL2C_LCB* p_lcb = l2cu_find_lcb_by_bd_addr(*bd_addr, BT_TRANSPORT_BR_EDR); if (p_lcb) { if (new_role == HCI_ROLE_CENTRAL) { p_lcb->SetLinkRoleAsCentral(); } else { p_lcb->SetLinkRoleAsPeripheral(); } /* Reset high priority link if needed */ if (hci_status == HCI_SUCCESS) l2cu_set_acl_priority(*bd_addr, p_lcb->acl_priority, true); } } /* Check if any LCB was waiting for switch to be completed */ tL2C_LCB* p_lcb = &l2cb.lcb_pool[0]; for (uint8_t xx = 0; xx < MAX_L2CAP_LINKS; xx++, p_lcb++) { if ((p_lcb->in_use) && (p_lcb->link_state == LST_CONNECTING_WAIT_SWITCH)) { l2cu_create_conn_after_switch(p_lcb); } } } /******************************************************************************* * * Function l2c_pin_code_request * * Description This function is called whan a pin-code request is received * on a connection. If there are no channels active yet on the * link, it extends the link first connection timer. Make sure * that inactivity timer is not extended if PIN code happens * to be after last ccb released. * * Returns void * ******************************************************************************/ void l2c_pin_code_request(const RawAddress& bd_addr) { tL2C_LCB* p_lcb = l2cu_find_lcb_by_bd_addr(bd_addr, BT_TRANSPORT_BR_EDR); if ((p_lcb) && (!p_lcb->ccb_queue.p_first_ccb)) { alarm_set_on_mloop(p_lcb->l2c_lcb_timer, L2CAP_LINK_CONNECT_EXT_TIMEOUT_MS, l2c_lcb_timer_timeout, p_lcb); } } /******************************************************************************* * * Function l2c_link_check_power_mode * * Description This function is called to check power mode. * * Returns true if link is going to be active from park * false if nothing to send or not in park mode * ******************************************************************************/ static bool l2c_link_check_power_mode(tL2C_LCB* p_lcb) { bool need_to_active = false; /* * We only switch park to active only if we have unsent packets */ if (list_is_empty(p_lcb->link_xmit_data_q)) { for (tL2C_CCB* p_ccb = p_lcb->ccb_queue.p_first_ccb; p_ccb; p_ccb = p_ccb->p_next_ccb) { if (!fixed_queue_is_empty(p_ccb->xmit_hold_q)) { need_to_active = true; break; } } } else { need_to_active = true; } /* if we have packets to send */ if (need_to_active && !p_lcb->is_transport_ble()) { /* check power mode */ tBTM_PM_MODE mode; if (BTM_ReadPowerMode(p_lcb->remote_bd_addr, &mode)) { if (mode == BTM_PM_STS_PENDING) { LOG_DEBUG("LCB(0x%x) is in PM pending state", p_lcb->Handle()); return true; } } } return false; } /******************************************************************************* * * Function l2c_link_check_send_pkts * * Description This function is called to check if it can send packets * to the Host Controller. It may be passed the address of * a packet to send. * * Returns void * ******************************************************************************/ void l2c_link_check_send_pkts(tL2C_LCB* p_lcb, uint16_t local_cid, BT_HDR* p_buf) { bool single_write = false; /* Save the channel ID for faster counting */ if (p_buf) { p_buf->event = local_cid; if (local_cid != 0) { single_write = true; } p_buf->layer_specific = 0; list_append(p_lcb->link_xmit_data_q, p_buf); if (p_lcb->link_xmit_quota == 0) { if (p_lcb->transport == BT_TRANSPORT_LE) l2cb.ble_check_round_robin = true; else l2cb.check_round_robin = true; } } /* If this is called from uncongested callback context break recursive *calling. ** This LCB will be served when receiving number of completed packet event. */ if (l2cb.is_cong_cback_context) { LOG_INFO("skipping, is_cong_cback_context=true"); return; } /* If we are in a scenario where there are not enough buffers for each link to ** have at least 1, then do a round-robin for all the LCBs */ if ((p_lcb == NULL) || (p_lcb->link_xmit_quota == 0)) { LOG_DEBUG("Round robin"); if (p_lcb == NULL) { p_lcb = l2cb.lcb_pool; } else if (!single_write) { p_lcb++; } /* Loop through, starting at the next */ for (int xx = 0; xx < MAX_L2CAP_LINKS; xx++, p_lcb++) { /* Check for wraparound */ if (p_lcb == &l2cb.lcb_pool[MAX_L2CAP_LINKS]) p_lcb = &l2cb.lcb_pool[0]; /* If controller window is full, nothing to do */ if (((l2cb.controller_xmit_window == 0 || (l2cb.round_robin_unacked >= l2cb.round_robin_quota)) && (p_lcb->transport == BT_TRANSPORT_BR_EDR)) || (p_lcb->transport == BT_TRANSPORT_LE && (l2cb.ble_round_robin_unacked >= l2cb.ble_round_robin_quota || l2cb.controller_le_xmit_window == 0))) { LOG_DEBUG("Skipping lcb %d due to controller window full", xx); continue; } if ((!p_lcb->in_use) || (p_lcb->partial_segment_being_sent) || (p_lcb->link_state != LST_CONNECTED) || (p_lcb->link_xmit_quota != 0) || (l2c_link_check_power_mode(p_lcb))) { LOG_DEBUG("Skipping lcb %d due to quota", xx); continue; } /* See if we can send anything from the Link Queue */ if (!list_is_empty(p_lcb->link_xmit_data_q)) { LOG_DEBUG("Sending to lower layer"); p_buf = (BT_HDR*)list_front(p_lcb->link_xmit_data_q); list_remove(p_lcb->link_xmit_data_q, p_buf); l2c_link_send_to_lower(p_lcb, p_buf); } else if (single_write) { /* If only doing one write, break out */ LOG_DEBUG("single_write is true, skipping"); break; } /* If nothing on the link queue, check the channel queue */ else { LOG_DEBUG("Check next buffer"); p_buf = l2cu_get_next_buffer_to_send(p_lcb); if (p_buf != NULL) { LOG_DEBUG("Sending next buffer"); l2c_link_send_to_lower(p_lcb, p_buf); } } } /* If we finished without using up our quota, no need for a safety check */ if ((l2cb.controller_xmit_window > 0) && (l2cb.round_robin_unacked < l2cb.round_robin_quota) && (p_lcb->transport == BT_TRANSPORT_BR_EDR)) l2cb.check_round_robin = false; if ((l2cb.controller_le_xmit_window > 0) && (l2cb.ble_round_robin_unacked < l2cb.ble_round_robin_quota) && (p_lcb->transport == BT_TRANSPORT_LE)) l2cb.ble_check_round_robin = false; } else /* if this is not round-robin service */ { /* If a partial segment is being sent, can't send anything else */ if ((p_lcb->partial_segment_being_sent) || (p_lcb->link_state != LST_CONNECTED) || (l2c_link_check_power_mode(p_lcb))) { LOG_INFO("A partial segment is being sent, cannot send anything else"); return; } LOG_DEBUG( "Direct send, transport=%d, xmit_window=%d, le_xmit_window=%d, " "sent_not_acked=%d, link_xmit_quota=%d", p_lcb->transport, l2cb.controller_xmit_window, l2cb.controller_le_xmit_window, p_lcb->sent_not_acked, p_lcb->link_xmit_quota); /* See if we can send anything from the link queue */ while (((l2cb.controller_xmit_window != 0 && (p_lcb->transport == BT_TRANSPORT_BR_EDR)) || (l2cb.controller_le_xmit_window != 0 && (p_lcb->transport == BT_TRANSPORT_LE))) && (p_lcb->sent_not_acked < p_lcb->link_xmit_quota)) { if (list_is_empty(p_lcb->link_xmit_data_q)) { LOG_DEBUG("No transmit data, skipping"); break; } LOG_DEBUG("Sending to lower layer"); p_buf = (BT_HDR*)list_front(p_lcb->link_xmit_data_q); list_remove(p_lcb->link_xmit_data_q, p_buf); l2c_link_send_to_lower(p_lcb, p_buf); } if (!single_write) { /* See if we can send anything for any channel */ LOG_DEBUG("Trying to send other data when single_write is false"); while (((l2cb.controller_xmit_window != 0 && (p_lcb->transport == BT_TRANSPORT_BR_EDR)) || (l2cb.controller_le_xmit_window != 0 && (p_lcb->transport == BT_TRANSPORT_LE))) && (p_lcb->sent_not_acked < p_lcb->link_xmit_quota)) { p_buf = l2cu_get_next_buffer_to_send(p_lcb); if (p_buf == NULL) { LOG_DEBUG("No next buffer, skipping"); break; } LOG_DEBUG("Sending to lower layer"); l2c_link_send_to_lower(p_lcb, p_buf); } } /* There is a special case where we have readjusted the link quotas and */ /* this link may have sent anything but some other link sent packets so */ /* so we may need a timer to kick off this link's transmissions. */ if ((!list_is_empty(p_lcb->link_xmit_data_q)) && (p_lcb->sent_not_acked < p_lcb->link_xmit_quota)) { alarm_set_on_mloop(p_lcb->l2c_lcb_timer, L2CAP_LINK_FLOW_CONTROL_TIMEOUT_MS, l2c_lcb_timer_timeout, p_lcb); } } } void l2c_OnHciModeChangeSendPendingPackets(RawAddress remote) { tL2C_LCB* p_lcb = l2cu_find_lcb_by_bd_addr(remote, BT_TRANSPORT_BR_EDR); if (p_lcb != NULL) { /* There might be any pending packets due to SNIFF or PENDING state */ /* Trigger L2C to start transmission of the pending packets. */ BTM_TRACE_DEBUG( "btm mode change to active; check l2c_link for outgoing packets"); l2c_link_check_send_pkts(p_lcb, 0, NULL); } } /******************************************************************************* * * Function l2c_link_send_to_lower * * Description This function queues the buffer for HCI transmission * ******************************************************************************/ static void l2c_link_send_to_lower_br_edr(tL2C_LCB* p_lcb, BT_HDR* p_buf) { const uint16_t acl_packet_size_classic = controller_get_interface()->get_acl_packet_size_classic(); const uint16_t link_xmit_quota = p_lcb->link_xmit_quota; const bool is_bdr_and_fits_in_buffer = bluetooth::shim::is_gd_acl_enabled() ? true : (p_buf->len <= acl_packet_size_classic); if (is_bdr_and_fits_in_buffer) { if (link_xmit_quota == 0) { l2cb.round_robin_unacked++; } p_lcb->sent_not_acked++; p_buf->layer_specific = 0; l2cb.controller_xmit_window--; } else { uint16_t num_segs = (p_buf->len - HCI_DATA_PREAMBLE_SIZE + acl_packet_size_classic - 1) / acl_packet_size_classic; /* If doing round-robin, then only 1 segment each time */ if (p_lcb->link_xmit_quota == 0) { num_segs = 1; p_lcb->partial_segment_being_sent = true; } else { /* Multi-segment packet. Make sure it can fit */ if (num_segs > l2cb.controller_xmit_window) { num_segs = l2cb.controller_xmit_window; p_lcb->partial_segment_being_sent = true; } if (num_segs > (p_lcb->link_xmit_quota - p_lcb->sent_not_acked)) { num_segs = (p_lcb->link_xmit_quota - p_lcb->sent_not_acked); p_lcb->partial_segment_being_sent = true; } } p_lcb->sent_not_acked += num_segs; p_buf->layer_specific = num_segs; l2cb.controller_xmit_window -= num_segs; if (p_lcb->link_xmit_quota == 0) l2cb.round_robin_unacked += num_segs; } acl_send_data_packet_br_edr(p_lcb->remote_bd_addr, p_buf); LOG_DEBUG("TotalWin=%d,Hndl=0x%x,Quota=%d,Unack=%d,RRQuota=%d,RRUnack=%d", l2cb.controller_xmit_window, p_lcb->Handle(), p_lcb->link_xmit_quota, p_lcb->sent_not_acked, l2cb.round_robin_quota, l2cb.round_robin_unacked); } static void l2c_link_send_to_lower_ble(tL2C_LCB* p_lcb, BT_HDR* p_buf) { const uint16_t acl_packet_size_ble = controller_get_interface()->get_acl_packet_size_ble(); const uint16_t link_xmit_quota = p_lcb->link_xmit_quota; const bool is_ble_and_fits_in_buffer = (p_buf->len <= acl_packet_size_ble); if (is_ble_and_fits_in_buffer) { if (link_xmit_quota == 0) { l2cb.ble_round_robin_unacked++; } p_lcb->sent_not_acked++; p_buf->layer_specific = 0; l2cb.controller_le_xmit_window--; } else { uint16_t num_segs = (p_buf->len - HCI_DATA_PREAMBLE_SIZE + acl_packet_size_ble - 1) / acl_packet_size_ble; /* If doing round-robin, then only 1 segment each time */ if (p_lcb->link_xmit_quota == 0) { num_segs = 1; p_lcb->partial_segment_being_sent = true; } else { /* Multi-segment packet. Make sure it can fit */ if (num_segs > l2cb.controller_le_xmit_window) { num_segs = l2cb.controller_le_xmit_window; p_lcb->partial_segment_being_sent = true; } if (num_segs > (p_lcb->link_xmit_quota - p_lcb->sent_not_acked)) { num_segs = (p_lcb->link_xmit_quota - p_lcb->sent_not_acked); p_lcb->partial_segment_being_sent = true; } } p_lcb->sent_not_acked += num_segs; p_buf->layer_specific = num_segs; l2cb.controller_le_xmit_window -= num_segs; if (p_lcb->link_xmit_quota == 0) l2cb.ble_round_robin_unacked += num_segs; } acl_send_data_packet_ble(p_lcb->remote_bd_addr, p_buf); LOG_DEBUG("TotalWin=%d,Hndl=0x%x,Quota=%d,Unack=%d,RRQuota=%d,RRUnack=%d", l2cb.controller_le_xmit_window, p_lcb->Handle(), p_lcb->link_xmit_quota, p_lcb->sent_not_acked, l2cb.ble_round_robin_quota, l2cb.ble_round_robin_unacked); } static void l2c_link_send_to_lower(tL2C_LCB* p_lcb, BT_HDR* p_buf) { if (p_lcb->transport == BT_TRANSPORT_BR_EDR) { l2c_link_send_to_lower_br_edr(p_lcb, p_buf); } else { l2c_link_send_to_lower_ble(p_lcb, p_buf); } } /******************************************************************************* * * Function l2c_link_process_num_completed_pkts * * Description This function is called when a "number-of-completed-packets" * event is received from the controller. It updates all the * LCB transmit counts. * * Returns void * ******************************************************************************/ void l2c_link_process_num_completed_pkts(uint8_t* p, uint8_t evt_len) { if (bluetooth::shim::is_gd_l2cap_enabled()) { return; } uint8_t num_handles, xx; uint16_t handle; uint16_t num_sent; tL2C_LCB* p_lcb; if (evt_len > 0) { STREAM_TO_UINT8(num_handles, p); } else { num_handles = 0; } if (num_handles > evt_len / (2 * sizeof(uint16_t))) { android_errorWriteLog(0x534e4554, "141617601"); num_handles = evt_len / (2 * sizeof(uint16_t)); } for (xx = 0; xx < num_handles; xx++) { STREAM_TO_UINT16(handle, p); /* Extract the handle */ handle = HCID_GET_HANDLE(handle); STREAM_TO_UINT16(num_sent, p); p_lcb = l2cu_find_lcb_by_handle(handle); if (p_lcb) { if (p_lcb && (p_lcb->transport == BT_TRANSPORT_LE)) l2cb.controller_le_xmit_window += num_sent; else { /* Maintain the total window to the controller */ l2cb.controller_xmit_window += num_sent; } /* If doing round-robin, adjust communal counts */ if (p_lcb->link_xmit_quota == 0) { if (p_lcb->transport == BT_TRANSPORT_LE) { /* Don't go negative */ if (l2cb.ble_round_robin_unacked > num_sent) l2cb.ble_round_robin_unacked -= num_sent; else l2cb.ble_round_robin_unacked = 0; } else { /* Don't go negative */ if (l2cb.round_robin_unacked > num_sent) l2cb.round_robin_unacked -= num_sent; else l2cb.round_robin_unacked = 0; } } /* Don't go negative */ if (p_lcb->sent_not_acked > num_sent) p_lcb->sent_not_acked -= num_sent; else p_lcb->sent_not_acked = 0; l2c_link_check_send_pkts(p_lcb, 0, NULL); /* If we were doing round-robin for low priority links, check 'em */ if ((p_lcb->acl_priority == L2CAP_PRIORITY_HIGH) && (l2cb.check_round_robin) && (l2cb.round_robin_unacked < l2cb.round_robin_quota)) { l2c_link_check_send_pkts(NULL, 0, NULL); } if ((p_lcb->transport == BT_TRANSPORT_LE) && (p_lcb->acl_priority == L2CAP_PRIORITY_HIGH) && ((l2cb.ble_check_round_robin) && (l2cb.ble_round_robin_unacked < l2cb.ble_round_robin_quota))) { l2c_link_check_send_pkts(NULL, 0, NULL); } } if (p_lcb) { if (p_lcb->transport == BT_TRANSPORT_LE) { LOG_DEBUG("TotalWin=%d,LinkUnack(0x%x)=%d,RRCheck=%d,RRUnack=%d", l2cb.controller_le_xmit_window, p_lcb->Handle(), p_lcb->sent_not_acked, l2cb.ble_check_round_robin, l2cb.ble_round_robin_unacked); } else { LOG_DEBUG("TotalWin=%d,LinkUnack(0x%x)=%d,RRCheck=%d,RRUnack=%d", l2cb.controller_xmit_window, p_lcb->Handle(), p_lcb->sent_not_acked, l2cb.check_round_robin, l2cb.round_robin_unacked); } } else { LOG_DEBUG("TotalWin=%d LE_Win: %d, Handle=0x%x, RRCheck=%d, RRUnack=%d", l2cb.controller_xmit_window, l2cb.controller_le_xmit_window, handle, l2cb.ble_check_round_robin, l2cb.ble_round_robin_unacked); } } } void l2c_packets_completed(uint16_t handle, uint16_t num_sent) { tL2C_LCB* p_lcb = l2cu_find_lcb_by_handle(handle); if (p_lcb == nullptr) { LOG_WARN("Received l2c packets completed for unknown ACL"); return; } p_lcb->update_outstanding_packets(num_sent); switch (p_lcb->transport) { case BT_TRANSPORT_BR_EDR: l2cb.controller_xmit_window += num_sent; if (p_lcb->is_round_robin_scheduling()) l2cb.update_outstanding_classic_packets(num_sent); break; case BT_TRANSPORT_LE: l2cb.controller_le_xmit_window += num_sent; if (p_lcb->is_round_robin_scheduling()) l2cb.update_outstanding_le_packets(num_sent); break; default: LOG_ERROR("Unknown transport received:%u", p_lcb->transport); return; } l2c_link_check_send_pkts(p_lcb, 0, NULL); if (p_lcb->is_high_priority()) { switch (p_lcb->transport) { case BT_TRANSPORT_LE: if (l2cb.ble_check_round_robin && l2cb.is_ble_round_robin_quota_available()) l2c_link_check_send_pkts(NULL, 0, NULL); break; case BT_TRANSPORT_BR_EDR: if (l2cb.check_round_robin && l2cb.is_classic_round_robin_quota_available()) { l2c_link_check_send_pkts(NULL, 0, NULL); } break; default: break; } } } /******************************************************************************* * * Function l2c_link_segments_xmitted * * Description This function is called from the HCI Interface when an ACL * data packet segment is transmitted. * * Returns void * ******************************************************************************/ void l2c_link_segments_xmitted(BT_HDR* p_msg) { uint8_t* p = (uint8_t*)(p_msg + 1) + p_msg->offset; /* Extract the handle */ uint16_t handle{HCI_INVALID_HANDLE}; STREAM_TO_UINT16(handle, p); handle = HCID_GET_HANDLE(handle); /* Find the LCB based on the handle */ tL2C_LCB* p_lcb = l2cu_find_lcb_by_handle(handle); if (p_lcb == nullptr) { LOG_WARN("Received segment complete for unknown connection handle:%d", handle); osi_free(p_msg); return; } if (p_lcb->link_state != LST_CONNECTED) { LOG_INFO("Received segment complete for unconnected connection handle:%d:", handle); osi_free(p_msg); return; } /* Enqueue the buffer to the head of the transmit queue, and see */ /* if we can transmit anything more. */ list_prepend(p_lcb->link_xmit_data_q, p_msg); p_lcb->partial_segment_being_sent = false; l2c_link_check_send_pkts(p_lcb, 0, NULL); } tBTM_STATUS l2cu_ConnectAclForSecurity(const RawAddress& bd_addr) { if (bluetooth::shim::is_gd_l2cap_enabled()) { bluetooth::shim::L2CA_ConnectForSecurity(bd_addr); return BTM_SUCCESS; } tL2C_LCB* p_lcb = l2cu_find_lcb_by_bd_addr(bd_addr, BT_TRANSPORT_BR_EDR); if (p_lcb && (p_lcb->link_state == LST_CONNECTED || p_lcb->link_state == LST_CONNECTING)) { LOG_WARN("Connection already exists"); return BTM_CMD_STARTED; } /* Make sure an L2cap link control block is available */ if (!p_lcb && (p_lcb = l2cu_allocate_lcb(bd_addr, true, BT_TRANSPORT_BR_EDR)) == NULL) { LOG_WARN("failed allocate LCB for %s", bd_addr.ToString().c_str()); return BTM_NO_RESOURCES; } l2cu_create_conn_br_edr(p_lcb); btm_acl_set_paging(true); return BTM_SUCCESS; } void l2cble_update_sec_act(const RawAddress& bd_addr, uint16_t sec_act) { tL2C_LCB* lcb = l2cu_find_lcb_by_bd_addr(bd_addr, BT_TRANSPORT_LE); lcb->sec_act = sec_act; } /****************************************************************************** * * Function l2cu_get_next_channel_in_rr * * Description get the next channel to send on a link. It also adjusts the * CCB queue to do a basic priority and round-robin scheduling. * * Returns pointer to CCB or NULL * ******************************************************************************/ tL2C_CCB* l2cu_get_next_channel_in_rr(tL2C_LCB* p_lcb) { tL2C_CCB* p_serve_ccb = NULL; tL2C_CCB* p_ccb; int i, j; /* scan all of priority until finding a channel to serve */ for (i = 0; (i < L2CAP_NUM_CHNL_PRIORITY) && (!p_serve_ccb); i++) { /* scan all channel within serving priority group until finding a channel to * serve */ for (j = 0; (j < p_lcb->rr_serv[p_lcb->rr_pri].num_ccb) && (!p_serve_ccb); j++) { /* scaning from next serving channel */ p_ccb = p_lcb->rr_serv[p_lcb->rr_pri].p_serve_ccb; if (!p_ccb) { LOG_ERROR("p_serve_ccb is NULL, rr_pri=%d", p_lcb->rr_pri); return NULL; } LOG_DEBUG("RR scan pri=%d, lcid=0x%04x, q_cout=%zu", p_ccb->ccb_priority, p_ccb->local_cid, fixed_queue_length(p_ccb->xmit_hold_q)); /* store the next serving channel */ /* this channel is the last channel of its priority group */ if ((p_ccb->p_next_ccb == NULL) || (p_ccb->p_next_ccb->ccb_priority != p_ccb->ccb_priority)) { /* next serving channel is set to the first channel in the group */ p_lcb->rr_serv[p_lcb->rr_pri].p_serve_ccb = p_lcb->rr_serv[p_lcb->rr_pri].p_first_ccb; } else { /* next serving channel is set to the next channel in the group */ p_lcb->rr_serv[p_lcb->rr_pri].p_serve_ccb = p_ccb->p_next_ccb; } if (p_ccb->chnl_state != CST_OPEN) continue; if (p_ccb->p_lcb->transport == BT_TRANSPORT_LE) { LOG_DEBUG("Connection oriented channel"); if (fixed_queue_is_empty(p_ccb->xmit_hold_q)) continue; } else { /* eL2CAP option in use */ if (p_ccb->peer_cfg.fcr.mode != L2CAP_FCR_BASIC_MODE) { if (p_ccb->fcrb.wait_ack || p_ccb->fcrb.remote_busy) continue; if (fixed_queue_is_empty(p_ccb->fcrb.retrans_q)) { if (fixed_queue_is_empty(p_ccb->xmit_hold_q)) continue; /* If in eRTM mode, check for window closure */ if ((p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) && (l2c_fcr_is_flow_controlled(p_ccb))) continue; } } else { if (fixed_queue_is_empty(p_ccb->xmit_hold_q)) continue; } } /* found a channel to serve */ p_serve_ccb = p_ccb; /* decrease quota of its priority group */ p_lcb->rr_serv[p_lcb->rr_pri].quota--; } /* if there is no more quota of the priority group or no channel to have * data to send */ if ((p_lcb->rr_serv[p_lcb->rr_pri].quota == 0) || (!p_serve_ccb)) { /* serve next priority group */ p_lcb->rr_pri = (p_lcb->rr_pri + 1) % L2CAP_NUM_CHNL_PRIORITY; /* initialize its quota */ p_lcb->rr_serv[p_lcb->rr_pri].quota = L2CAP_GET_PRIORITY_QUOTA(p_lcb->rr_pri); } } if (p_serve_ccb) { LOG_DEBUG("RR service pri=%d, quota=%d, lcid=0x%04x", p_serve_ccb->ccb_priority, p_lcb->rr_serv[p_serve_ccb->ccb_priority].quota, p_serve_ccb->local_cid); } return p_serve_ccb; } /****************************************************************************** * * Function l2cu_get_next_buffer_to_send * * Description get the next buffer to send on a link. It also adjusts the * CCB queue to do a basic priority and round-robin scheduling. * * Returns pointer to buffer or NULL * ******************************************************************************/ BT_HDR* l2cu_get_next_buffer_to_send(tL2C_LCB* p_lcb) { tL2C_CCB* p_ccb; BT_HDR* p_buf; /* Highest priority are fixed channels */ int xx; for (xx = 0; xx < L2CAP_NUM_FIXED_CHNLS; xx++) { p_ccb = p_lcb->p_fixed_ccbs[xx]; if (p_ccb == NULL) continue; /* eL2CAP option in use */ if (p_ccb->peer_cfg.fcr.mode != L2CAP_FCR_BASIC_MODE) { if (p_ccb->fcrb.wait_ack || p_ccb->fcrb.remote_busy) continue; /* No more checks needed if sending from the reatransmit queue */ if (fixed_queue_is_empty(p_ccb->fcrb.retrans_q)) { if (fixed_queue_is_empty(p_ccb->xmit_hold_q)) continue; /* If in eRTM mode, check for window closure */ if ((p_ccb->peer_cfg.fcr.mode == L2CAP_FCR_ERTM_MODE) && (l2c_fcr_is_flow_controlled(p_ccb))) continue; } p_buf = l2c_fcr_get_next_xmit_sdu_seg(p_ccb, 0); if (p_buf != NULL) { l2cu_check_channel_congestion(p_ccb); l2cu_set_acl_hci_header(p_buf, p_ccb); return (p_buf); } } else { if (!fixed_queue_is_empty(p_ccb->xmit_hold_q)) { p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->xmit_hold_q); if (NULL == p_buf) { LOG_ERROR("No data to be sent"); return (NULL); } l2cu_check_channel_congestion(p_ccb); l2cu_set_acl_hci_header(p_buf, p_ccb); return (p_buf); } } } /* get next serving channel in round-robin */ p_ccb = l2cu_get_next_channel_in_rr(p_lcb); /* Return if no buffer */ if (p_ccb == NULL) return (NULL); if (p_ccb->p_lcb->transport == BT_TRANSPORT_LE) { /* Check credits */ if (p_ccb->peer_conn_cfg.credits == 0) { LOG_DEBUG("No credits to send packets"); return NULL; } bool last_piece_of_sdu = false; p_buf = l2c_lcc_get_next_xmit_sdu_seg(p_ccb, &last_piece_of_sdu); p_ccb->peer_conn_cfg.credits--; if (last_piece_of_sdu) { // TODO: send callback up the stack. Investigate setting p_cbi->cb to // notify after controller ack send. } } else { if (p_ccb->peer_cfg.fcr.mode != L2CAP_FCR_BASIC_MODE) { p_buf = l2c_fcr_get_next_xmit_sdu_seg(p_ccb, 0); if (p_buf == NULL) return (NULL); } else { p_buf = (BT_HDR*)fixed_queue_try_dequeue(p_ccb->xmit_hold_q); if (NULL == p_buf) { LOG_ERROR("#2: No data to be sent"); return (NULL); } } } if (p_ccb->p_rcb && p_ccb->p_rcb->api.pL2CA_TxComplete_Cb && (p_ccb->peer_cfg.fcr.mode != L2CAP_FCR_ERTM_MODE)) (*p_ccb->p_rcb->api.pL2CA_TxComplete_Cb)(p_ccb->local_cid, 1); l2cu_check_channel_congestion(p_ccb); l2cu_set_acl_hci_header(p_buf, p_ccb); return (p_buf); }