Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / mac80211 / mesh_ps.c
diff --git a/kernel/net/mac80211/mesh_ps.c b/kernel/net/mac80211/mesh_ps.c
new file mode 100644 (file)
index 0000000..ad8b377
--- /dev/null
@@ -0,0 +1,605 @@
+/*
+ * Copyright 2012-2013, Marco Porsch <marco.porsch@s2005.tu-chemnitz.de>
+ * Copyright 2012-2013, cozybit Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include "mesh.h"
+#include "wme.h"
+
+
+/* mesh PS management */
+
+/**
+ * mps_qos_null_get - create pre-addressed QoS Null frame for mesh powersave
+ */
+static struct sk_buff *mps_qos_null_get(struct sta_info *sta)
+{
+       struct ieee80211_sub_if_data *sdata = sta->sdata;
+       struct ieee80211_local *local = sdata->local;
+       struct ieee80211_hdr *nullfunc; /* use 4addr header */
+       struct sk_buff *skb;
+       int size = sizeof(*nullfunc);
+       __le16 fc;
+
+       skb = dev_alloc_skb(local->hw.extra_tx_headroom + size + 2);
+       if (!skb)
+               return NULL;
+       skb_reserve(skb, local->hw.extra_tx_headroom);
+
+       nullfunc = (struct ieee80211_hdr *) skb_put(skb, size);
+       fc = cpu_to_le16(IEEE80211_FTYPE_DATA | IEEE80211_STYPE_QOS_NULLFUNC);
+       ieee80211_fill_mesh_addresses(nullfunc, &fc, sta->sta.addr,
+                                     sdata->vif.addr);
+       nullfunc->frame_control = fc;
+       nullfunc->duration_id = 0;
+       nullfunc->seq_ctrl = 0;
+       /* no address resolution for this frame -> set addr 1 immediately */
+       memcpy(nullfunc->addr1, sta->sta.addr, ETH_ALEN);
+       memset(skb_put(skb, 2), 0, 2); /* append QoS control field */
+       ieee80211_mps_set_frame_flags(sdata, sta, nullfunc);
+
+       return skb;
+}
+
+/**
+ * mps_qos_null_tx - send a QoS Null to indicate link-specific power mode
+ */
+static void mps_qos_null_tx(struct sta_info *sta)
+{
+       struct sk_buff *skb;
+
+       skb = mps_qos_null_get(sta);
+       if (!skb)
+               return;
+
+       mps_dbg(sta->sdata, "announcing peer-specific power mode to %pM\n",
+               sta->sta.addr);
+
+       /* don't unintentionally start a MPSP */
+       if (!test_sta_flag(sta, WLAN_STA_PS_STA)) {
+               u8 *qc = ieee80211_get_qos_ctl((void *) skb->data);
+
+               qc[0] |= IEEE80211_QOS_CTL_EOSP;
+       }
+
+       ieee80211_tx_skb(sta->sdata, skb);
+}
+
+/**
+ * ieee80211_mps_local_status_update - track status of local link-specific PMs
+ *
+ * @sdata: local mesh subif
+ *
+ * sets the non-peer power mode and triggers the driver PS (re-)configuration
+ * Return BSS_CHANGED_BEACON if a beacon update is necessary.
+ */
+u32 ieee80211_mps_local_status_update(struct ieee80211_sub_if_data *sdata)
+{
+       struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+       struct sta_info *sta;
+       bool peering = false;
+       int light_sleep_cnt = 0;
+       int deep_sleep_cnt = 0;
+       u32 changed = 0;
+       enum nl80211_mesh_power_mode nonpeer_pm;
+
+       rcu_read_lock();
+       list_for_each_entry_rcu(sta, &sdata->local->sta_list, list) {
+               if (sdata != sta->sdata)
+                       continue;
+
+               switch (sta->plink_state) {
+               case NL80211_PLINK_OPN_SNT:
+               case NL80211_PLINK_OPN_RCVD:
+               case NL80211_PLINK_CNF_RCVD:
+                       peering = true;
+                       break;
+               case NL80211_PLINK_ESTAB:
+                       if (sta->local_pm == NL80211_MESH_POWER_LIGHT_SLEEP)
+                               light_sleep_cnt++;
+                       else if (sta->local_pm == NL80211_MESH_POWER_DEEP_SLEEP)
+                               deep_sleep_cnt++;
+                       break;
+               default:
+                       break;
+               }
+       }
+       rcu_read_unlock();
+
+       /*
+        * Set non-peer mode to active during peering/scanning/authentication
+        * (see IEEE802.11-2012 13.14.8.3). The non-peer mesh power mode is
+        * deep sleep if the local STA is in light or deep sleep towards at
+        * least one mesh peer (see 13.14.3.1). Otherwise, set it to the
+        * user-configured default value.
+        */
+       if (peering) {
+               mps_dbg(sdata, "setting non-peer PM to active for peering\n");
+               nonpeer_pm = NL80211_MESH_POWER_ACTIVE;
+       } else if (light_sleep_cnt || deep_sleep_cnt) {
+               mps_dbg(sdata, "setting non-peer PM to deep sleep\n");
+               nonpeer_pm = NL80211_MESH_POWER_DEEP_SLEEP;
+       } else {
+               mps_dbg(sdata, "setting non-peer PM to user value\n");
+               nonpeer_pm = ifmsh->mshcfg.power_mode;
+       }
+
+       /* need update if sleep counts move between 0 and non-zero */
+       if (ifmsh->nonpeer_pm != nonpeer_pm ||
+           !ifmsh->ps_peers_light_sleep != !light_sleep_cnt ||
+           !ifmsh->ps_peers_deep_sleep != !deep_sleep_cnt)
+               changed = BSS_CHANGED_BEACON;
+
+       ifmsh->nonpeer_pm = nonpeer_pm;
+       ifmsh->ps_peers_light_sleep = light_sleep_cnt;
+       ifmsh->ps_peers_deep_sleep = deep_sleep_cnt;
+
+       return changed;
+}
+
+/**
+ * ieee80211_mps_set_sta_local_pm - set local PM towards a mesh STA
+ *
+ * @sta: mesh STA
+ * @pm: the power mode to set
+ * Return BSS_CHANGED_BEACON if a beacon update is in order.
+ */
+u32 ieee80211_mps_set_sta_local_pm(struct sta_info *sta,
+                                  enum nl80211_mesh_power_mode pm)
+{
+       struct ieee80211_sub_if_data *sdata = sta->sdata;
+
+       if (sta->local_pm == pm)
+               return 0;
+
+       mps_dbg(sdata, "local STA operates in mode %d with %pM\n",
+               pm, sta->sta.addr);
+
+       sta->local_pm = pm;
+
+       /*
+        * announce peer-specific power mode transition
+        * (see IEEE802.11-2012 13.14.3.2 and 13.14.3.3)
+        */
+       if (sta->plink_state == NL80211_PLINK_ESTAB)
+               mps_qos_null_tx(sta);
+
+       return ieee80211_mps_local_status_update(sdata);
+}
+
+/**
+ * ieee80211_mps_set_frame_flags - set mesh PS flags in FC (and QoS Control)
+ *
+ * @sdata: local mesh subif
+ * @sta: mesh STA
+ * @hdr: 802.11 frame header
+ *
+ * see IEEE802.11-2012 8.2.4.1.7 and 8.2.4.5.11
+ *
+ * NOTE: sta must be given when an individually-addressed QoS frame header
+ * is handled, for group-addressed and management frames it is not used
+ */
+void ieee80211_mps_set_frame_flags(struct ieee80211_sub_if_data *sdata,
+                                  struct sta_info *sta,
+                                  struct ieee80211_hdr *hdr)
+{
+       enum nl80211_mesh_power_mode pm;
+       u8 *qc;
+
+       if (WARN_ON(is_unicast_ether_addr(hdr->addr1) &&
+                   ieee80211_is_data_qos(hdr->frame_control) &&
+                   !sta))
+               return;
+
+       if (is_unicast_ether_addr(hdr->addr1) &&
+           ieee80211_is_data_qos(hdr->frame_control) &&
+           sta->plink_state == NL80211_PLINK_ESTAB)
+               pm = sta->local_pm;
+       else
+               pm = sdata->u.mesh.nonpeer_pm;
+
+       if (pm == NL80211_MESH_POWER_ACTIVE)
+               hdr->frame_control &= cpu_to_le16(~IEEE80211_FCTL_PM);
+       else
+               hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM);
+
+       if (!ieee80211_is_data_qos(hdr->frame_control))
+               return;
+
+       qc = ieee80211_get_qos_ctl(hdr);
+
+       if ((is_unicast_ether_addr(hdr->addr1) &&
+            pm == NL80211_MESH_POWER_DEEP_SLEEP) ||
+           (is_multicast_ether_addr(hdr->addr1) &&
+            sdata->u.mesh.ps_peers_deep_sleep > 0))
+               qc[1] |= (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
+       else
+               qc[1] &= ~(IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8);
+}
+
+/**
+ * ieee80211_mps_sta_status_update - update buffering status of neighbor STA
+ *
+ * @sta: mesh STA
+ *
+ * called after change of peering status or non-peer/peer-specific power mode
+ */
+void ieee80211_mps_sta_status_update(struct sta_info *sta)
+{
+       enum nl80211_mesh_power_mode pm;
+       bool do_buffer;
+
+       /* For non-assoc STA, prevent buffering or frame transmission */
+       if (sta->sta_state < IEEE80211_STA_ASSOC)
+               return;
+
+       /*
+        * use peer-specific power mode if peering is established and the
+        * peer's power mode is known
+        */
+       if (sta->plink_state == NL80211_PLINK_ESTAB &&
+           sta->peer_pm != NL80211_MESH_POWER_UNKNOWN)
+               pm = sta->peer_pm;
+       else
+               pm = sta->nonpeer_pm;
+
+       do_buffer = (pm != NL80211_MESH_POWER_ACTIVE);
+
+       /* clear the MPSP flags for non-peers or active STA */
+       if (sta->plink_state != NL80211_PLINK_ESTAB) {
+               clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
+               clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
+       } else if (!do_buffer) {
+               clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
+       }
+
+       /* Don't let the same PS state be set twice */
+       if (test_sta_flag(sta, WLAN_STA_PS_STA) == do_buffer)
+               return;
+
+       if (do_buffer) {
+               set_sta_flag(sta, WLAN_STA_PS_STA);
+               atomic_inc(&sta->sdata->u.mesh.ps.num_sta_ps);
+               mps_dbg(sta->sdata, "start PS buffering frames towards %pM\n",
+                       sta->sta.addr);
+       } else {
+               ieee80211_sta_ps_deliver_wakeup(sta);
+       }
+}
+
+static void mps_set_sta_peer_pm(struct sta_info *sta,
+                               struct ieee80211_hdr *hdr)
+{
+       enum nl80211_mesh_power_mode pm;
+       u8 *qc = ieee80211_get_qos_ctl(hdr);
+
+       /*
+        * Test Power Management field of frame control (PW) and
+        * mesh power save level subfield of QoS control field (PSL)
+        *
+        * | PM | PSL| Mesh PM |
+        * +----+----+---------+
+        * | 0  |Rsrv|  Active |
+        * | 1  | 0  |  Light  |
+        * | 1  | 1  |  Deep   |
+        */
+       if (ieee80211_has_pm(hdr->frame_control)) {
+               if (qc[1] & (IEEE80211_QOS_CTL_MESH_PS_LEVEL >> 8))
+                       pm = NL80211_MESH_POWER_DEEP_SLEEP;
+               else
+                       pm = NL80211_MESH_POWER_LIGHT_SLEEP;
+       } else {
+               pm = NL80211_MESH_POWER_ACTIVE;
+       }
+
+       if (sta->peer_pm == pm)
+               return;
+
+       mps_dbg(sta->sdata, "STA %pM enters mode %d\n",
+               sta->sta.addr, pm);
+
+       sta->peer_pm = pm;
+
+       ieee80211_mps_sta_status_update(sta);
+}
+
+static void mps_set_sta_nonpeer_pm(struct sta_info *sta,
+                                  struct ieee80211_hdr *hdr)
+{
+       enum nl80211_mesh_power_mode pm;
+
+       if (ieee80211_has_pm(hdr->frame_control))
+               pm = NL80211_MESH_POWER_DEEP_SLEEP;
+       else
+               pm = NL80211_MESH_POWER_ACTIVE;
+
+       if (sta->nonpeer_pm == pm)
+               return;
+
+       mps_dbg(sta->sdata, "STA %pM sets non-peer mode to %d\n",
+               sta->sta.addr, pm);
+
+       sta->nonpeer_pm = pm;
+
+       ieee80211_mps_sta_status_update(sta);
+}
+
+/**
+ * ieee80211_mps_rx_h_sta_process - frame receive handler for mesh powersave
+ *
+ * @sta: STA info that transmitted the frame
+ * @hdr: IEEE 802.11 (QoS) Header
+ */
+void ieee80211_mps_rx_h_sta_process(struct sta_info *sta,
+                                   struct ieee80211_hdr *hdr)
+{
+       if (is_unicast_ether_addr(hdr->addr1) &&
+           ieee80211_is_data_qos(hdr->frame_control)) {
+               /*
+                * individually addressed QoS Data/Null frames contain
+                * peer link-specific PS mode towards the local STA
+                */
+               mps_set_sta_peer_pm(sta, hdr);
+
+               /* check for mesh Peer Service Period trigger frames */
+               ieee80211_mpsp_trigger_process(ieee80211_get_qos_ctl(hdr),
+                                              sta, false, false);
+       } else {
+               /*
+                * can only determine non-peer PS mode
+                * (see IEEE802.11-2012 8.2.4.1.7)
+                */
+               mps_set_sta_nonpeer_pm(sta, hdr);
+       }
+}
+
+
+/* mesh PS frame release */
+
+static void mpsp_trigger_send(struct sta_info *sta, bool rspi, bool eosp)
+{
+       struct ieee80211_sub_if_data *sdata = sta->sdata;
+       struct sk_buff *skb;
+       struct ieee80211_hdr *nullfunc;
+       struct ieee80211_tx_info *info;
+       u8 *qc;
+
+       skb = mps_qos_null_get(sta);
+       if (!skb)
+               return;
+
+       nullfunc = (struct ieee80211_hdr *) skb->data;
+       if (!eosp)
+               nullfunc->frame_control |=
+                               cpu_to_le16(IEEE80211_FCTL_MOREDATA);
+       /*
+        * | RSPI | EOSP |  MPSP triggering   |
+        * +------+------+--------------------+
+        * |  0   |  0   | local STA is owner |
+        * |  0   |  1   | no MPSP (MPSP end) |
+        * |  1   |  0   | both STA are owner |
+        * |  1   |  1   | peer STA is owner  | see IEEE802.11-2012 13.14.9.2
+        */
+       qc = ieee80211_get_qos_ctl(nullfunc);
+       if (rspi)
+               qc[1] |= (IEEE80211_QOS_CTL_RSPI >> 8);
+       if (eosp)
+               qc[0] |= IEEE80211_QOS_CTL_EOSP;
+
+       info = IEEE80211_SKB_CB(skb);
+
+       info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER |
+                      IEEE80211_TX_CTL_REQ_TX_STATUS;
+
+       mps_dbg(sdata, "sending MPSP trigger%s%s to %pM\n",
+               rspi ? " RSPI" : "", eosp ? " EOSP" : "", sta->sta.addr);
+
+       ieee80211_tx_skb(sdata, skb);
+}
+
+/**
+ * mpsp_qos_null_append - append QoS Null frame to MPSP skb queue if needed
+ *
+ * To properly end a mesh MPSP the last transmitted frame has to set the EOSP
+ * flag in the QoS Control field. In case the current tailing frame is not a
+ * QoS Data frame, append a QoS Null to carry the flag.
+ */
+static void mpsp_qos_null_append(struct sta_info *sta,
+                                struct sk_buff_head *frames)
+{
+       struct ieee80211_sub_if_data *sdata = sta->sdata;
+       struct sk_buff *new_skb, *skb = skb_peek_tail(frames);
+       struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
+       struct ieee80211_tx_info *info;
+
+       if (ieee80211_is_data_qos(hdr->frame_control))
+               return;
+
+       new_skb = mps_qos_null_get(sta);
+       if (!new_skb)
+               return;
+
+       mps_dbg(sdata, "appending QoS Null in MPSP towards %pM\n",
+               sta->sta.addr);
+       /*
+        * This frame has to be transmitted last. Assign lowest priority to
+        * make sure it cannot pass other frames when releasing multiple ACs.
+        */
+       new_skb->priority = 1;
+       skb_set_queue_mapping(new_skb, IEEE80211_AC_BK);
+       ieee80211_set_qos_hdr(sdata, new_skb);
+
+       info = IEEE80211_SKB_CB(new_skb);
+       info->control.vif = &sdata->vif;
+       info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING;
+
+       __skb_queue_tail(frames, new_skb);
+}
+
+/**
+ * mps_frame_deliver - transmit frames during mesh powersave
+ *
+ * @sta: STA info to transmit to
+ * @n_frames: number of frames to transmit. -1 for all
+ */
+static void mps_frame_deliver(struct sta_info *sta, int n_frames)
+{
+       struct ieee80211_local *local = sta->sdata->local;
+       int ac;
+       struct sk_buff_head frames;
+       struct sk_buff *skb;
+       bool more_data = false;
+
+       skb_queue_head_init(&frames);
+
+       /* collect frame(s) from buffers */
+       for (ac = 0; ac < IEEE80211_NUM_ACS; ac++) {
+               while (n_frames != 0) {
+                       skb = skb_dequeue(&sta->tx_filtered[ac]);
+                       if (!skb) {
+                               skb = skb_dequeue(
+                                       &sta->ps_tx_buf[ac]);
+                               if (skb)
+                                       local->total_ps_buffered--;
+                       }
+                       if (!skb)
+                               break;
+                       n_frames--;
+                       __skb_queue_tail(&frames, skb);
+               }
+
+               if (!skb_queue_empty(&sta->tx_filtered[ac]) ||
+                   !skb_queue_empty(&sta->ps_tx_buf[ac]))
+                       more_data = true;
+       }
+
+       /* nothing to send? -> EOSP */
+       if (skb_queue_empty(&frames)) {
+               mpsp_trigger_send(sta, false, true);
+               return;
+       }
+
+       /* in a MPSP make sure the last skb is a QoS Data frame */
+       if (test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
+               mpsp_qos_null_append(sta, &frames);
+
+       mps_dbg(sta->sdata, "sending %d frames to PS STA %pM\n",
+               skb_queue_len(&frames), sta->sta.addr);
+
+       /* prepare collected frames for transmission */
+       skb_queue_walk(&frames, skb) {
+               struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+               struct ieee80211_hdr *hdr = (void *) skb->data;
+
+               /*
+                * Tell TX path to send this frame even though the
+                * STA may still remain is PS mode after this frame
+                * exchange.
+                */
+               info->flags |= IEEE80211_TX_CTL_NO_PS_BUFFER;
+
+               if (more_data || !skb_queue_is_last(&frames, skb))
+                       hdr->frame_control |=
+                               cpu_to_le16(IEEE80211_FCTL_MOREDATA);
+               else
+                       hdr->frame_control &=
+                               cpu_to_le16(~IEEE80211_FCTL_MOREDATA);
+
+               if (skb_queue_is_last(&frames, skb) &&
+                   ieee80211_is_data_qos(hdr->frame_control)) {
+                       u8 *qoshdr = ieee80211_get_qos_ctl(hdr);
+
+                       /* MPSP trigger frame ends service period */
+                       *qoshdr |= IEEE80211_QOS_CTL_EOSP;
+                       info->flags |= IEEE80211_TX_CTL_REQ_TX_STATUS;
+               }
+       }
+
+       ieee80211_add_pending_skbs(local, &frames);
+       sta_info_recalc_tim(sta);
+}
+
+/**
+ * ieee80211_mpsp_trigger_process - track status of mesh Peer Service Periods
+ *
+ * @qc: QoS Control field
+ * @sta: peer to start a MPSP with
+ * @tx: frame was transmitted by the local STA
+ * @acked: frame has been transmitted successfully
+ *
+ * NOTE: active mode STA may only serve as MPSP owner
+ */
+void ieee80211_mpsp_trigger_process(u8 *qc, struct sta_info *sta,
+                                   bool tx, bool acked)
+{
+       u8 rspi = qc[1] & (IEEE80211_QOS_CTL_RSPI >> 8);
+       u8 eosp = qc[0] & IEEE80211_QOS_CTL_EOSP;
+
+       if (tx) {
+               if (rspi && acked)
+                       set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
+
+               if (eosp)
+                       clear_sta_flag(sta, WLAN_STA_MPSP_OWNER);
+               else if (acked &&
+                        test_sta_flag(sta, WLAN_STA_PS_STA) &&
+                        !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
+                       mps_frame_deliver(sta, -1);
+       } else {
+               if (eosp)
+                       clear_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
+               else if (sta->local_pm != NL80211_MESH_POWER_ACTIVE)
+                       set_sta_flag(sta, WLAN_STA_MPSP_RECIPIENT);
+
+               if (rspi && !test_and_set_sta_flag(sta, WLAN_STA_MPSP_OWNER))
+                       mps_frame_deliver(sta, -1);
+       }
+}
+
+/**
+ * ieee80211_mps_frame_release - release frames buffered due to mesh power save
+ *
+ * @sta: mesh STA
+ * @elems: IEs of beacon or probe response
+ *
+ * For peers if we have individually-addressed frames buffered or the peer
+ * indicates buffered frames, send a corresponding MPSP trigger frame. Since
+ * we do not evaluate the awake window duration, QoS Nulls are used as MPSP
+ * trigger frames. If the neighbour STA is not a peer, only send single frames.
+ */
+void ieee80211_mps_frame_release(struct sta_info *sta,
+                                struct ieee802_11_elems *elems)
+{
+       int ac, buffer_local = 0;
+       bool has_buffered = false;
+
+       if (sta->plink_state == NL80211_PLINK_ESTAB)
+               has_buffered = ieee80211_check_tim(elems->tim, elems->tim_len,
+                                                  sta->llid);
+
+       if (has_buffered)
+               mps_dbg(sta->sdata, "%pM indicates buffered frames\n",
+                       sta->sta.addr);
+
+       /* only transmit to PS STA with announced, non-zero awake window */
+       if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
+           (!elems->awake_window || !le16_to_cpu(*elems->awake_window)))
+               return;
+
+       if (!test_sta_flag(sta, WLAN_STA_MPSP_OWNER))
+               for (ac = 0; ac < IEEE80211_NUM_ACS; ac++)
+                       buffer_local += skb_queue_len(&sta->ps_tx_buf[ac]) +
+                                       skb_queue_len(&sta->tx_filtered[ac]);
+
+       if (!has_buffered && !buffer_local)
+               return;
+
+       if (sta->plink_state == NL80211_PLINK_ESTAB)
+               mpsp_trigger_send(sta, has_buffered, !buffer_local);
+       else
+               mps_frame_deliver(sta, 1);
+}