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author | Michal Kazior <michal.kazior@tieto.com> | 2012-06-26 14:37:16 +0200 |
---|---|---|
committer | Johannes Berg <johannes.berg@intel.com> | 2012-10-16 20:22:41 +0200 |
commit | d01a1e658606a0a69100f49c2ef09aacaf74d3e7 (patch) | |
tree | 30de068699ed95997ad44f4d0f703a6deb0ad95b /net/mac80211 | |
parent | ddffeb8c4d0331609ef2581d84de4d763607bd37 (diff) | |
download | op-kernel-dev-d01a1e658606a0a69100f49c2ef09aacaf74d3e7.zip op-kernel-dev-d01a1e658606a0a69100f49c2ef09aacaf74d3e7.tar.gz |
mac80211: introduce channel context skeleton code
Channel context are the foundation for multi-channel
operation. They are are immutable and are re-created
(or re-used if other interfaces are bound to a certain
channel and a compatible channel type) on channel
switching.
This is an initial implementation and more features
will come in separate patches.
Signed-off-by: Michal Kazior <michal.kazior@tieto.com>
[some changes including RCU protection]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/mac80211')
-rw-r--r-- | net/mac80211/chan.c | 147 | ||||
-rw-r--r-- | net/mac80211/ieee80211_i.h | 35 | ||||
-rw-r--r-- | net/mac80211/main.c | 3 |
3 files changed, 185 insertions, 0 deletions
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 0bfc914..4ae9486 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -168,3 +168,150 @@ bool ieee80211_set_channel_type(struct ieee80211_local *local, return true; } + +static struct ieee80211_chanctx * +ieee80211_find_chanctx(struct ieee80211_local *local, + struct ieee80211_channel *channel, + enum nl80211_channel_type channel_type, + enum ieee80211_chanctx_mode mode) +{ + struct ieee80211_chanctx *ctx; + + lockdep_assert_held(&local->chanctx_mtx); + + if (mode == IEEE80211_CHANCTX_EXCLUSIVE) + return NULL; + if (WARN_ON(!channel)) + return NULL; + + list_for_each_entry(ctx, &local->chanctx_list, list) { + if (ctx->mode == IEEE80211_CHANCTX_EXCLUSIVE) + continue; + if (ctx->conf.channel != channel) + continue; + if (ctx->conf.channel_type != channel_type) + continue; + + return ctx; + } + + return NULL; +} + +static struct ieee80211_chanctx * +ieee80211_new_chanctx(struct ieee80211_local *local, + struct ieee80211_channel *channel, + enum nl80211_channel_type channel_type, + enum ieee80211_chanctx_mode mode) +{ + struct ieee80211_chanctx *ctx; + + 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.channel = channel; + ctx->conf.channel_type = channel_type; + ctx->mode = mode; + + list_add(&ctx->list, &local->chanctx_list); + + return ctx; +} + +static void ieee80211_free_chanctx(struct ieee80211_local *local, + struct ieee80211_chanctx *ctx) +{ + lockdep_assert_held(&local->chanctx_mtx); + + WARN_ON_ONCE(ctx->refcount != 0); + + list_del(&ctx->list); + kfree_rcu(ctx, rcu_head); +} + +static int ieee80211_assign_vif_chanctx(struct ieee80211_sub_if_data *sdata, + struct ieee80211_chanctx *ctx) +{ + struct ieee80211_local *local __maybe_unused = sdata->local; + + lockdep_assert_held(&local->chanctx_mtx); + + rcu_assign_pointer(sdata->vif.chanctx_conf, &ctx->conf); + ctx->refcount++; + + return 0; +} + +static void ieee80211_unassign_vif_chanctx(struct ieee80211_sub_if_data *sdata, + struct ieee80211_chanctx *ctx) +{ + struct ieee80211_local *local __maybe_unused = sdata->local; + + lockdep_assert_held(&local->chanctx_mtx); + + ctx->refcount--; + rcu_assign_pointer(sdata->vif.chanctx_conf, NULL); +} + +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); +} + +int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata, + struct ieee80211_channel *channel, + enum nl80211_channel_type channel_type, + enum ieee80211_chanctx_mode mode) +{ + struct ieee80211_local *local = sdata->local; + struct ieee80211_chanctx *ctx; + int ret; + + mutex_lock(&local->chanctx_mtx); + __ieee80211_vif_release_channel(sdata); + + ctx = ieee80211_find_chanctx(local, channel, channel_type, mode); + if (!ctx) + ctx = ieee80211_new_chanctx(local, channel, channel_type, mode); + if (IS_ERR(ctx)) { + ret = PTR_ERR(ctx); + goto out; + } + + 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; + } + + out: + mutex_unlock(&local->chanctx_mtx); + return ret; +} + +void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata) +{ + mutex_lock(&sdata->local->chanctx_mtx); + __ieee80211_vif_release_channel(sdata); + mutex_unlock(&sdata->local->chanctx_mtx); +} diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 8c80455..9a058e58d 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -658,6 +658,30 @@ enum ieee80211_sdata_state_bits { SDATA_STATE_OFFCHANNEL, }; +/** + * enum ieee80211_chanctx_mode - channel context configuration mode + * + * @IEEE80211_CHANCTX_SHARED: channel context may be used by + * multiple interfaces + * @IEEE80211_CHANCTX_EXCLUSIVE: channel context can be used + * only by a single interface. This can be used for example for + * non-fixed channel IBSS. + */ +enum ieee80211_chanctx_mode { + IEEE80211_CHANCTX_SHARED, + IEEE80211_CHANCTX_EXCLUSIVE +}; + +struct ieee80211_chanctx { + struct list_head list; + struct rcu_head rcu_head; + + enum ieee80211_chanctx_mode mode; + int refcount; + + struct ieee80211_chanctx_conf conf; +}; + struct ieee80211_sub_if_data { struct list_head list; @@ -987,6 +1011,10 @@ struct ieee80211_local { struct ieee80211_channel *tmp_channel; enum nl80211_channel_type tmp_channel_type; + /* channel contexts */ + struct list_head chanctx_list; + struct mutex chanctx_mtx; + /* SNMP counters */ /* dot11CountersTable */ u32 dot11TransmittedFragmentCount; @@ -1510,6 +1538,13 @@ bool ieee80211_set_channel_type(struct ieee80211_local *local, enum nl80211_channel_type ieee80211_ht_oper_to_channel_type(struct ieee80211_ht_operation *ht_oper); +int __must_check +ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata, + struct ieee80211_channel *channel, + enum nl80211_channel_type channel_type, + enum ieee80211_chanctx_mode mode); +void ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata); + #ifdef CONFIG_MAC80211_NOINLINE #define debug_noinline noinline #else diff --git a/net/mac80211/main.c b/net/mac80211/main.c index c80c449..9be3ef1 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -626,6 +626,9 @@ struct ieee80211_hw *ieee80211_alloc_hw(size_t priv_data_len, spin_lock_init(&local->filter_lock); spin_lock_init(&local->queue_stop_reason_lock); + INIT_LIST_HEAD(&local->chanctx_list); + mutex_init(&local->chanctx_mtx); + /* * The rx_skb_queue is only accessed from tasklets, * but other SKB queues are used from within IRQ |