diff options
Diffstat (limited to 'net/mac80211/chan.c')
| -rw-r--r-- | net/mac80211/chan.c | 540 |
1 files changed, 540 insertions, 0 deletions
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c new file mode 100644 index 0000000..03e8d2e --- /dev/null +++ b/net/mac80211/chan.c @@ -0,0 +1,540 @@ +/* + * mac80211 - channel management + */ + +#include <linux/nl80211.h> +#include <linux/export.h> +#include <linux/rtnetlink.h> +#include <net/cfg80211.h> +#include "ieee80211_i.h" +#include "driver-ops.h" + +static void ieee80211_change_chanctx(struct ieee80211_local *local, + struct ieee80211_chanctx *ctx, + const struct cfg80211_chan_def *chandef) +{ + if (cfg80211_chandef_identical(&ctx->conf.def, chandef)) + return; + + WARN_ON(!cfg80211_chandef_compatible(&ctx->conf.def, chandef)); + + ctx->conf.def = *chandef; + drv_change_chanctx(local, ctx, IEEE80211_CHANCTX_CHANGE_WIDTH); + + if (!local->use_chanctx) { + local->_oper_chandef = *chandef; + ieee80211_hw_config(local, 0); + } +} + +static struct ieee80211_chanctx * +ieee80211_find_chanctx(struct ieee80211_local *local, + const struct cfg80211_chan_def *chandef, + enum ieee80211_chanctx_mode mode) +{ + struct ieee80211_chanctx *ctx; + + lockdep_assert_held(&local->chanctx_mtx); + + if (mode == IEEE80211_CHANCTX_EXCLUSIVE) + return NULL; + + list_for_each_entry(ctx, &local->chanctx_list, list) { + const struct cfg80211_chan_def *compat; + + if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE) + continue; + + compat = cfg80211_chandef_compatible(&ctx->conf.def, chandef); + if (!compat) + continue; + + ieee80211_change_chanctx(local, ctx, compat); + + return ctx; + } + + return NULL; +} + +static bool ieee80211_is_radar_required(struct ieee80211_local *local) +{ + struct ieee80211_sub_if_data *sdata; + + rcu_read_lock(); + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + if (sdata->radar_required) { + rcu_read_unlock(); + return true; + } + } + rcu_read_unlock(); + + return false; +} + +static struct ieee80211_chanctx * +ieee80211_new_chanctx(struct ieee80211_local *local, + const struct cfg80211_chan_def *chandef, + enum ieee80211_chanctx_mode mode) +{ + struct ieee80211_chanctx *ctx; + u32 changed; + int err; + + lockdep_assert_held(&local->chanctx_mtx); + + ctx = kzalloc(sizeof(*ctx) + local->hw.chanctx_data_size, GFP_KERNEL); + if (!ctx) + return ERR_PTR(-ENOMEM); + + ctx->conf.def = *chandef; + ctx->conf.rx_chains_static = 1; + ctx->conf.rx_chains_dynamic = 1; + ctx->mode = mode; + ctx->conf.radar_enabled = ieee80211_is_radar_required(local); + if (!local->use_chanctx) + local->hw.conf.radar_enabled = ctx->conf.radar_enabled; + + /* acquire mutex to prevent idle from changing */ + mutex_lock(&local->mtx); + /* turn idle off *before* setting channel -- some drivers need that */ + changed = ieee80211_idle_off(local); + if (changed) + ieee80211_hw_config(local, changed); + + if (!local->use_chanctx) { + local->_oper_chandef = *chandef; + ieee80211_hw_config(local, 0); + } else { + err = drv_add_chanctx(local, ctx); + if (err) { + kfree(ctx); + ctx = ERR_PTR(err); + + ieee80211_recalc_idle(local); + goto out; + } + } + + /* and keep the mutex held until the new chanctx is on the list */ + list_add_rcu(&ctx->list, &local->chanctx_list); + + out: + mutex_unlock(&local->mtx); + + return ctx; +} + +static void ieee80211_free_chanctx(struct ieee80211_local *local, + struct ieee80211_chanctx *ctx) +{ + bool check_single_channel = false; + lockdep_assert_held(&local->chanctx_mtx); + + WARN_ON_ONCE(ctx->refcount != 0); + + if (!local->use_chanctx) { + struct cfg80211_chan_def *chandef = &local->_oper_chandef; + chandef->width = NL80211_CHAN_WIDTH_20_NOHT; + chandef->center_freq1 = chandef->chan->center_freq; + chandef->center_freq2 = 0; + + /* NOTE: Disabling radar is only valid here for + * single channel context. To be sure, check it ... + */ + if (local->hw.conf.radar_enabled) + check_single_channel = true; + local->hw.conf.radar_enabled = false; + + ieee80211_hw_config(local, 0); + } else { + drv_remove_chanctx(local, ctx); + } + + list_del_rcu(&ctx->list); + kfree_rcu(ctx, rcu_head); + + /* throw a warning if this wasn't the only channel context. */ + WARN_ON(check_single_channel && !list_empty(&local->chanctx_list)); + + mutex_lock(&local->mtx); + ieee80211_recalc_idle(local); + mutex_unlock(&local->mtx); +} + +static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata, + struct ieee80211_chanctx *ctx) +{ + struct ieee80211_local *local = sdata->local; + int ret; + + lockdep_assert_held(&local->chanctx_mtx); + + ret = drv_assign_vif_chanctx(local, sdata, ctx); + if (ret) + return ret; + + rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf); + ctx->refcount++; + + ieee80211_recalc_txpower(sdata); + sdata->vif.bss_conf.idle = false; + + if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE && + sdata->vif.type != NL80211_IFTYPE_MONITOR) + ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE); + + return 0; +} + +static void ieee80211_recalc_chanctx_chantype(struct ieee80211_local *local, + struct ieee80211_chanctx *ctx) +{ + struct ieee80211_chanctx_conf *conf = &ctx->conf; + struct ieee80211_sub_if_data *sdata; + const struct cfg80211_chan_def *compat = NULL; + + lockdep_assert_held(&local->chanctx_mtx); + + rcu_read_lock(); + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + + if (!ieee80211_sdata_running(sdata)) + continue; + if (rcu_access_pointer(sdata->vif.chanctx_conf) != conf) + continue; + + if (!compat) + compat = &sdata->vif.bss_conf.chandef; + + compat = cfg80211_chandef_compatible( + &sdata->vif.bss_conf.chandef, compat); + if (!compat) + break; + } + rcu_read_unlock(); + + if (WARN_ON_ONCE(!compat)) + return; + + ieee80211_change_chanctx(local, ctx, compat); +} + +static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata, + struct ieee80211_chanctx *ctx) +{ + struct ieee80211_local *local = sdata->local; + + lockdep_assert_held(&local->chanctx_mtx); + + ctx->refcount--; + rcu_assign_pointer(sdata->vif.chanctx_conf, NULL); + + sdata->vif.bss_conf.idle = true; + + if (sdata->vif.type != NL80211_IFTYPE_P2P_DEVICE && + sdata->vif.type != NL80211_IFTYPE_MONITOR) + ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_IDLE); + + drv_unassign_vif_chanctx(local, sdata, ctx); + + if (ctx->refcount > 0) { + ieee80211_recalc_chanctx_chantype(sdata->local, ctx); + ieee80211_recalc_smps_chanctx(local, ctx); + ieee80211_recalc_radar_chanctx(local, ctx); + } +} + +static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_chanctx_conf *conf; + struct ieee80211_chanctx *ctx; + + lockdep_assert_held(&local->chanctx_mtx); + + conf = rcu_dereference_protected(sdata->vif.chanctx_conf, + lockdep_is_held(&local->chanctx_mtx)); + if (!conf) + return; + + ctx = container_of(conf, struct ieee80211_chanctx, conf); + + ieee80211_unassign_vif_chanctx(sdata, ctx); + if (ctx->refcount == 0) + ieee80211_free_chanctx(local, ctx); +} + +void ieee80211_recalc_radar_chanctx(struct ieee80211_local *local, + struct ieee80211_chanctx *chanctx) +{ + bool radar_enabled; + + lockdep_assert_held(&local->chanctx_mtx); + + radar_enabled = ieee80211_is_radar_required(local); + + if (radar_enabled == chanctx->conf.radar_enabled) + return; + + chanctx->conf.radar_enabled = radar_enabled; + local->radar_detect_enabled = chanctx->conf.radar_enabled; + + if (!local->use_chanctx) { + local->hw.conf.radar_enabled = chanctx->conf.radar_enabled; + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + } + + drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RADAR); +} + +void ieee80211_recalc_smps_chanctx(struct ieee80211_local *local, + struct ieee80211_chanctx *chanctx) +{ + struct ieee80211_sub_if_data *sdata; + u8 rx_chains_static, rx_chains_dynamic; + + lockdep_assert_held(&local->chanctx_mtx); + + rx_chains_static = 1; + rx_chains_dynamic = 1; + + rcu_read_lock(); + list_for_each_entry_rcu(sdata, &local->interfaces, list) { + u8 needed_static, needed_dynamic; + + if (!ieee80211_sdata_running(sdata)) + continue; + + if (rcu_access_pointer(sdata->vif.chanctx_conf) != + &chanctx->conf) + continue; + + switch (sdata->vif.type) { + case NL80211_IFTYPE_P2P_DEVICE: + continue; + case NL80211_IFTYPE_STATION: + if (!sdata->u.mgd.associated) + continue; + break; + case NL80211_IFTYPE_AP_VLAN: + continue; + case NL80211_IFTYPE_AP: + case NL80211_IFTYPE_ADHOC: + case NL80211_IFTYPE_WDS: + case NL80211_IFTYPE_MESH_POINT: + break; + default: + WARN_ON_ONCE(1); + } + + switch (sdata->smps_mode) { + default: + WARN_ONCE(1, "Invalid SMPS mode %d\n", + sdata->smps_mode); + /* fall through */ + case IEEE80211_SMPS_OFF: + needed_static = sdata->needed_rx_chains; + needed_dynamic = sdata->needed_rx_chains; + break; + case IEEE80211_SMPS_DYNAMIC: + needed_static = 1; + needed_dynamic = sdata->needed_rx_chains; + break; + case IEEE80211_SMPS_STATIC: + needed_static = 1; + needed_dynamic = 1; + break; + } + + rx_chains_static = max(rx_chains_static, needed_static); + rx_chains_dynamic = max(rx_chains_dynamic, needed_dynamic); + } + rcu_read_unlock(); + + if (!local->use_chanctx) { + if (rx_chains_static > 1) + local->smps_mode = IEEE80211_SMPS_OFF; + else if (rx_chains_dynamic > 1) + local->smps_mode = IEEE80211_SMPS_DYNAMIC; + else + local->smps_mode = IEEE80211_SMPS_STATIC; + ieee80211_hw_config(local, 0); + } + + if (rx_chains_static == chanctx->conf.rx_chains_static && + rx_chains_dynamic == chanctx->conf.rx_chains_dynamic) + return; + + chanctx->conf.rx_chains_static = rx_chains_static; + chanctx->conf.rx_chains_dynamic = rx_chains_dynamic; + drv_change_chanctx(local, chanctx, IEEE80211_CHANCTX_CHANGE_RX_CHAINS); +} + +int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata, + const struct cfg80211_chan_def *chandef, + enum ieee80211_chanctx_mode mode) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_chanctx *ctx; + int ret; + + WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev)); + + mutex_lock(&local->chanctx_mtx); + __ieee80211_vif_release_channel(sdata); + + ctx = ieee80211_find_chanctx(local, chandef, mode); + if (!ctx) + ctx = ieee80211_new_chanctx(local, chandef, mode); + if (IS_ERR(ctx)) { + ret = PTR_ERR(ctx); + goto out; + } + + sdata->vif.bss_conf.chandef = *chandef; + + ret = ieee80211_assign_vif_chanctx(sdata, ctx); + if (ret) { + /* if assign fails refcount stays the same */ + if (ctx->refcount == 0) + ieee80211_free_chanctx(local, ctx); + goto out; + } + + ieee80211_recalc_smps_chanctx(local, ctx); + ieee80211_recalc_radar_chanctx(local, ctx); + out: + mutex_unlock(&local->chanctx_mtx); + return ret; +} + +int ieee80211_vif_change_bandwidth(struct ieee80211_sub_if_data *sdata, + const struct cfg80211_chan_def *chandef, + u32 *changed) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_chanctx_conf *conf; + struct ieee80211_chanctx *ctx; + int ret; + + if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, chandef, + IEEE80211_CHAN_DISABLED)) + return -EINVAL; + + mutex_lock(&local->chanctx_mtx); + if (cfg80211_chandef_identical(chandef, &sdata->vif.bss_conf.chandef)) { + ret = 0; + goto out; + } + + if (chandef->width == NL80211_CHAN_WIDTH_20_NOHT || + sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT) { + ret = -EINVAL; + goto out; + } + + conf = rcu_dereference_protected(sdata->vif.chanctx_conf, + lockdep_is_held(&local->chanctx_mtx)); + if (!conf) { + ret = -EINVAL; + goto out; + } + + ctx = container_of(conf, struct ieee80211_chanctx, conf); + if (!cfg80211_chandef_compatible(&conf->def, chandef)) { + ret = -EINVAL; + goto out; + } + + sdata->vif.bss_conf.chandef = *chandef; + + ieee80211_recalc_chanctx_chantype(local, ctx); + + *changed |= BSS_CHANGED_BANDWIDTH; + ret = 0; + out: + mutex_unlock(&local->chanctx_mtx); + return ret; +} + +void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) +{ + WARN_ON(sdata->dev && netif_carrier_ok(sdata->dev)); + + mutex_lock(&sdata->local->chanctx_mtx); + __ieee80211_vif_release_channel(sdata); + mutex_unlock(&sdata->local->chanctx_mtx); +} + +void ieee80211_vif_vlan_copy_chanctx(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_sub_if_data *ap; + struct ieee80211_chanctx_conf *conf; + + if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP_VLAN || !sdata->bss)) + return; + + ap = container_of(sdata->bss, struct ieee80211_sub_if_data, u.ap); + + mutex_lock(&local->chanctx_mtx); + + conf = rcu_dereference_protected(ap->vif.chanctx_conf, + lockdep_is_held(&local->chanctx_mtx)); + rcu_assign_pointer(sdata->vif.chanctx_conf, conf); + mutex_unlock(&local->chanctx_mtx); +} + +void ieee80211_vif_copy_chanctx_to_vlans(struct ieee80211_sub_if_data *sdata, + bool clear) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_sub_if_data *vlan; + struct ieee80211_chanctx_conf *conf; + + ASSERT_RTNL(); + + if (WARN_ON(sdata->vif.type != NL80211_IFTYPE_AP)) + return; + + mutex_lock(&local->chanctx_mtx); + + /* + * Check that conf exists, even when clearing this function + * must be called with the AP's channel context still there + * as it would otherwise cause VLANs to have an invalid + * channel context pointer for a while, possibly pointing + * to a channel context that has already been freed. + */ + conf = rcu_dereference_protected(sdata->vif.chanctx_conf, + lockdep_is_held(&local->chanctx_mtx)); + WARN_ON(!conf); + + if (clear) + conf = NULL; + + list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) + rcu_assign_pointer(vlan->vif.chanctx_conf, conf); + + mutex_unlock(&local->chanctx_mtx); +} + +void ieee80211_iter_chan_contexts_atomic( + struct ieee80211_hw *hw, + void (*iter)(struct ieee80211_hw *hw, + struct ieee80211_chanctx_conf *chanctx_conf, + void *data), + void *iter_data) +{ + struct ieee80211_local *local = hw_to_local(hw); + struct ieee80211_chanctx *ctx; + + rcu_read_lock(); + list_for_each_entry_rcu(ctx, &local->chanctx_list, list) + if (ctx->driver_present) + iter(hw, &ctx->conf, iter_data); + rcu_read_unlock(); +} +EXPORT_SYMBOL_GPL(ieee80211_iter_chan_contexts_atomic); |