From 4352b8aee98005853aa63f57d6377282de17a33f Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 23 Aug 2026 13:28:57 -0700 Subject: Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux Pull I3C updates from Alexandre Belloni: "A new driver this cycle, for the AMD AXI I3C controller. There are also new features such as IBI wakeup support, SETAASA device discovery and ACPI support for the the DAA methods, meaning we can now communicate with the SPD devices on DDR5 modules. New driver: - AMD AXI I3C master controller Subsystem: - I3C Common Command Code (CCC) handling improvements, especially around GET CCCs - SETAASA device discovery support - ACPI support for all existing DAA methods like SETDASA, SETNEWDA as well as I2C devices on I3C bus - IBI-based wakeup support Drivers: - dw: SETAASA support - mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C controller support, PIO queue management support for HCI v1.2 - renesas: improve suspend to RAM support, add runtime PM support" * tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits) i3c: dw: reduce do_daa time if there's no client i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2 i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode i3c: dw: rename "pclk" to "apb" to match dt-binding i3c: dw: make struct dw_i3c_cmd smaller i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding i3c: renesas: Don't register devices when ENTDAA times out i3c: master: dw-i3c-master: fix OD timing for first broadcast i3c: mipi-i3c-hci: Advertise IBI wakeup capability i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev() i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI i3c: master: Reject IBI requests from non-IBI-capable devices i3c: master: Add helper to query bus wakeup requirements i3c: master: Report wakeup events for IBIs i3c: master: Support IBI-based wakeup capability i3c: master: Fix potential UAF in i3c_device_match() i3c: master: Fix potential UAF in i3c_device_uevent() i3c: Make dev->desc locking assumptions explicit i3c: master: Fix use-after-free of master->this ... --- net/mac80211/mesh_sync.c | 215 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 215 insertions(+) create mode 100644 net/mac80211/mesh_sync.c (limited to 'net/mac80211/mesh_sync.c') diff --git a/net/mac80211/mesh_sync.c b/net/mac80211/mesh_sync.c new file mode 100644 index 000000000..24a68eef7 --- /dev/null +++ b/net/mac80211/mesh_sync.c @@ -0,0 +1,215 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright 2011-2012, Pavel Zubarev + * Copyright 2011-2012, Marco Porsch + * Copyright 2011-2012, cozybit Inc. + * Copyright (C) 2021,2023 Intel Corporation + */ + +#include "ieee80211_i.h" +#include "mesh.h" +#include "driver-ops.h" + +/* This is not in the standard. It represents a tolerable tsf drift below + * which we do no TSF adjustment. + */ +#define TOFFSET_MINIMUM_ADJUSTMENT 10 + +/* This is not in the standard. It is a margin added to the + * Toffset setpoint to mitigate TSF overcorrection + * introduced by TSF adjustment latency. + */ +#define TOFFSET_SET_MARGIN 20 + +/* This is not in the standard. It represents the maximum Toffset jump above + * which we'll invalidate the Toffset setpoint and choose a new setpoint. This + * could be, for instance, in case a neighbor is restarted and its TSF counter + * reset. + */ +#define TOFFSET_MAXIMUM_ADJUSTMENT 800 /* 0.8 ms */ + +struct sync_method { + u8 method; + struct ieee80211_mesh_sync_ops ops; +}; + +/** + * mesh_peer_tbtt_adjusting - check if an mp is currently adjusting its TBTT + * + * @cfg: mesh config element from the mesh peer (or %NULL) + * + * Returns: If the mesh peer is currently adjusting its TBTT + */ +static bool mesh_peer_tbtt_adjusting(const struct ieee80211_meshconf_ie *cfg) +{ + return cfg && + (cfg->meshconf_cap & IEEE80211_MESHCONF_CAPAB_TBTT_ADJUSTING); +} + +void mesh_sync_adjust_tsf(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; + /* sdata->vif.bss_conf.beacon_int in 1024us units, 0.04% */ + u64 beacon_int_fraction = sdata->vif.bss_conf.beacon_int * 1024 / 2500; + u64 tsf; + u64 tsfdelta; + + spin_lock_bh(&ifmsh->sync_offset_lock); + if (ifmsh->sync_offset_clockdrift_max < beacon_int_fraction) { + msync_dbg(sdata, "TSF : max clockdrift=%lld; adjusting\n", + (long long) ifmsh->sync_offset_clockdrift_max); + tsfdelta = -ifmsh->sync_offset_clockdrift_max; + ifmsh->sync_offset_clockdrift_max = 0; + } else { + msync_dbg(sdata, "TSF : max clockdrift=%lld; adjusting by %llu\n", + (long long) ifmsh->sync_offset_clockdrift_max, + (unsigned long long) beacon_int_fraction); + tsfdelta = -beacon_int_fraction; + ifmsh->sync_offset_clockdrift_max -= beacon_int_fraction; + } + spin_unlock_bh(&ifmsh->sync_offset_lock); + + if (local->ops->offset_tsf) { + drv_offset_tsf(local, sdata, tsfdelta); + } else { + tsf = drv_get_tsf(local, sdata); + if (tsf != -1ULL) + drv_set_tsf(local, sdata, tsf + tsfdelta); + } +} + +static void +mesh_sync_offset_rx_bcn_presp(struct ieee80211_sub_if_data *sdata, u16 stype, + struct ieee80211_mgmt *mgmt, unsigned int len, + const struct ieee80211_meshconf_ie *mesh_cfg, + struct ieee80211_rx_status *rx_status) +{ + struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; + struct ieee80211_local *local = sdata->local; + struct sta_info *sta; + u64 t_t, t_r; + + WARN_ON(ifmsh->mesh_sp_id != IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET); + + /* standard mentions only beacons */ + if (stype != IEEE80211_STYPE_BEACON) + return; + + /* + * Get time when timestamp field was received. If we don't + * have rx timestamps, then use current tsf as an approximation. + * drv_get_tsf() must be called before entering the rcu-read + * section. + */ + if (ieee80211_have_rx_timestamp(rx_status)) + t_r = ieee80211_calculate_rx_timestamp(&local->hw, rx_status, + len + FCS_LEN, 24); + else + t_r = drv_get_tsf(local, sdata); + + rcu_read_lock(); + sta = sta_info_get(sdata, mgmt->sa); + if (!sta) + goto no_sync; + + /* check offset sync conditions (13.13.2.2.1) + * + * TODO also sync to + * dot11MeshNbrOffsetMaxNeighbor non-peer non-MBSS neighbors + */ + + if (mesh_peer_tbtt_adjusting(mesh_cfg)) { + msync_dbg(sdata, "STA %pM : is adjusting TBTT\n", + sta->sta.addr); + goto no_sync; + } + + /* Timing offset calculation (see 13.13.2.2.2) */ + t_t = le64_to_cpu(mgmt->u.beacon.timestamp); + sta->mesh->t_offset = t_t - t_r; + + if (test_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN)) { + s64 t_clockdrift = sta->mesh->t_offset_setpoint - sta->mesh->t_offset; + msync_dbg(sdata, + "STA %pM : t_offset=%lld, t_offset_setpoint=%lld, t_clockdrift=%lld\n", + sta->sta.addr, (long long) sta->mesh->t_offset, + (long long) sta->mesh->t_offset_setpoint, + (long long) t_clockdrift); + + if (t_clockdrift > TOFFSET_MAXIMUM_ADJUSTMENT || + t_clockdrift < -TOFFSET_MAXIMUM_ADJUSTMENT) { + msync_dbg(sdata, + "STA %pM : t_clockdrift=%lld too large, setpoint reset\n", + sta->sta.addr, + (long long) t_clockdrift); + clear_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN); + goto no_sync; + } + + spin_lock_bh(&ifmsh->sync_offset_lock); + if (t_clockdrift > ifmsh->sync_offset_clockdrift_max) + ifmsh->sync_offset_clockdrift_max = t_clockdrift; + spin_unlock_bh(&ifmsh->sync_offset_lock); + } else { + sta->mesh->t_offset_setpoint = sta->mesh->t_offset - TOFFSET_SET_MARGIN; + set_sta_flag(sta, WLAN_STA_TOFFSET_KNOWN); + msync_dbg(sdata, + "STA %pM : offset was invalid, t_offset=%lld\n", + sta->sta.addr, + (long long) sta->mesh->t_offset); + } + +no_sync: + rcu_read_unlock(); +} + +static void mesh_sync_offset_adjust_tsf(struct ieee80211_sub_if_data *sdata, + struct beacon_data *beacon) +{ + struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; + + WARN_ON(ifmsh->mesh_sp_id != IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET); + WARN_ON(!rcu_read_lock_held()); + + spin_lock_bh(&ifmsh->sync_offset_lock); + + if (ifmsh->sync_offset_clockdrift_max > TOFFSET_MINIMUM_ADJUSTMENT) { + /* Since adjusting the tsf here would + * require a possibly blocking call + * to the driver tsf setter, we punt + * the tsf adjustment to the mesh tasklet + */ + msync_dbg(sdata, + "TSF : kicking off TSF adjustment with clockdrift_max=%lld\n", + ifmsh->sync_offset_clockdrift_max); + set_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags); + } else { + msync_dbg(sdata, + "TSF : max clockdrift=%lld; too small to adjust\n", + (long long)ifmsh->sync_offset_clockdrift_max); + ifmsh->sync_offset_clockdrift_max = 0; + } + spin_unlock_bh(&ifmsh->sync_offset_lock); +} + +static const struct sync_method sync_methods[] = { + { + .method = IEEE80211_SYNC_METHOD_NEIGHBOR_OFFSET, + .ops = { + .rx_bcn_presp = &mesh_sync_offset_rx_bcn_presp, + .adjust_tsf = &mesh_sync_offset_adjust_tsf, + } + }, +}; + +const struct ieee80211_mesh_sync_ops *ieee80211_mesh_sync_ops_get(u8 method) +{ + int i; + + for (i = 0 ; i < ARRAY_SIZE(sync_methods); ++i) { + if (sync_methods[i].method == method) + return &sync_methods[i].ops; + } + return NULL; +} -- cgit v1.3.1