Fixes yet another deadlock on calling sta_info_flush() with the sdata_lock() held. Should make it easier to reason about locking in the future, since the sdata_lock() is now held on all mesh work.
Signed-off-by: Thomas Pedersen <[email protected]> --- net/mac80211/ieee80211_i.h | 1 + net/mac80211/mesh.c | 43 +++++++++++++++++++++++++++++++------------ net/mac80211/mesh.h | 2 ++ 3 files changed, 34 insertions(+), 12 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 9eed6f1..b4937fc 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -542,6 +542,7 @@ struct ieee80211_if_mesh { struct timer_list mesh_path_root_timer; unsigned long wrkq_flags; + unsigned long mbss_changed; u8 mesh_id[IEEE80211_MAX_MESH_ID_LEN]; size_t mesh_id_len; diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index d5faf91..288aad2 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -161,11 +161,8 @@ void mesh_sta_cleanup(struct sta_info *sta) del_timer_sync(&sta->plink_timer); } - if (changed) { - sdata_lock(sdata); + if (changed) ieee80211_mbss_info_change_notify(sdata, changed); - sdata_unlock(sdata); - } } int mesh_rmc_init(struct ieee80211_sub_if_data *sdata) @@ -719,14 +716,15 @@ ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata) void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata, u32 changed) { - if (sdata->vif.bss_conf.enable_beacon && - (changed & (BSS_CHANGED_BEACON | - BSS_CHANGED_HT | - BSS_CHANGED_BASIC_RATES | - BSS_CHANGED_BEACON_INT))) - if (ieee80211_mesh_rebuild_beacon(sdata)) - return; - ieee80211_bss_info_change_notify(sdata, changed); + struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; + u32 bit; + + /* if we race with running work, worst case this work becomes a noop */ + for_each_set_bit(bit, (unsigned long *)&changed, + sizeof(changed) * BITS_PER_BYTE) + set_bit(BIT(bit), &ifmsh->mbss_changed); + set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags); + ieee80211_queue_work(&sdata->local->hw, &sdata->work); } int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata) @@ -969,6 +967,25 @@ out: sdata_unlock(sdata); } +static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; +#define TEST_CHANGED_BIT(bit) \ + test_and_clear_bit(bit, &ifmsh->mbss_changed) + + u32 changed = TEST_CHANGED_BIT(BSS_CHANGED_BEACON) | + TEST_CHANGED_BIT(BSS_CHANGED_HT) | + TEST_CHANGED_BIT(BSS_CHANGED_BASIC_RATES) | + TEST_CHANGED_BIT(BSS_CHANGED_BEACON_INT); +#undef TEST_CHANGED_BIT + + if (sdata->vif.bss_conf.enable_beacon && changed) + if (ieee80211_mesh_rebuild_beacon(sdata)) + return; + + ieee80211_bss_info_change_notify(sdata, changed); +} + void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata) { struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh; @@ -999,6 +1016,8 @@ void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata) if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags)) mesh_sync_adjust_tbtt(sdata); + if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags)) + mesh_bss_info_changed(sdata); out: sdata_unlock(sdata); } diff --git a/net/mac80211/mesh.h b/net/mac80211/mesh.h index 8b4d9a3..be28f9b 100644 --- a/net/mac80211/mesh.h +++ b/net/mac80211/mesh.h @@ -57,6 +57,7 @@ enum mesh_path_flags { * grow * @MESH_WORK_ROOT: the mesh root station needs to send a frame * @MESH_WORK_DRIFT_ADJUST: time to compensate for clock drift relative to other + * @MESH_WORK_MBSS_CHANGED: rebuild beacon and notify driver of BSS changes * mesh nodes */ enum mesh_deferred_task_flags { @@ -65,6 +66,7 @@ enum mesh_deferred_task_flags { MESH_WORK_GROW_MPP_TABLE, MESH_WORK_ROOT, MESH_WORK_DRIFT_ADJUST, + MESH_WORK_MBSS_CHANGED, }; /** -- 1.7.10.4 _______________________________________________ Devel mailing list [email protected] http://lists.open80211s.org/cgi-bin/mailman/listinfo/devel
