1 files changed, 282 insertions, 0 deletions

diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index 3b81e6df3f34..d32e304eeb4b 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -14,6 +14,7 @@
 #include "wme.h"
 #include "ieee80211_i.h"
 #include "mesh.h"
+#include <linux/rhashtable.h>
 
 static void mesh_path_free_rcu(struct mesh_table *tbl, struct mesh_path *mpath);
 
@@ -32,6 +33,41 @@ static const struct rhashtable_params mesh_rht_params = {
 	.hashfn = mesh_table_hash,
 };
 
+static const struct rhashtable_params fast_tx_rht_params = {
+	.nelem_hint = 10,
+	.automatic_shrinking = true,
+	.key_len = ETH_ALEN,
+	.key_offset = offsetof(struct ieee80211_mesh_fast_tx, addr_key),
+	.head_offset = offsetof(struct ieee80211_mesh_fast_tx, rhash),
+	.hashfn = mesh_table_hash,
+};
+
+static void __mesh_fast_tx_entry_free(void *ptr, void *tblptr)
+{
+	struct ieee80211_mesh_fast_tx *entry = ptr;
+
+	kfree_rcu(entry, fast_tx.rcu_head);
+}
+
+static void mesh_fast_tx_deinit(struct ieee80211_sub_if_data *sdata)
+{
+	struct mesh_tx_cache *cache;
+
+	cache = &sdata->u.mesh.tx_cache;
+	rhashtable_free_and_destroy(&cache->rht,
+				    __mesh_fast_tx_entry_free, NULL);
+}
+
+static void mesh_fast_tx_init(struct ieee80211_sub_if_data *sdata)
+{
+	struct mesh_tx_cache *cache;
+
+	cache = &sdata->u.mesh.tx_cache;
+	rhashtable_init(&cache->rht, &fast_tx_rht_params);
+	INIT_HLIST_HEAD(&cache->walk_head);
+	spin_lock_init(&cache->walk_lock);
+}
+
 static inline bool mpath_expired(struct mesh_path *mpath)
 {
 	return (mpath->flags & MESH_PATH_ACTIVE) &&
@@ -381,6 +417,243 @@ struct mesh_path *mesh_path_new(struct ieee80211_sub_if_data *sdata,
 	return new_mpath;
 }
 
+static void mesh_fast_tx_entry_free(struct mesh_tx_cache *cache,
+				    struct ieee80211_mesh_fast_tx *entry)
+{
+	hlist_del_rcu(&entry->walk_list);
+	rhashtable_remove_fast(&cache->rht, &entry->rhash, fast_tx_rht_params);
+	kfree_rcu(entry, fast_tx.rcu_head);
+}
+
+struct ieee80211_mesh_fast_tx *
+mesh_fast_tx_get(struct ieee80211_sub_if_data *sdata, const u8 *addr)
+{
+	struct ieee80211_mesh_fast_tx *entry;
+	struct mesh_tx_cache *cache;
+
+	cache = &sdata->u.mesh.tx_cache;
+	entry = rhashtable_lookup(&cache->rht, addr, fast_tx_rht_params);
+	if (!entry)
+		return NULL;
+
+	if (!(entry->mpath->flags & MESH_PATH_ACTIVE) ||
+	    mpath_expired(entry->mpath)) {
+		spin_lock_bh(&cache->walk_lock);
+		entry = rhashtable_lookup(&cache->rht, addr, fast_tx_rht_params);
+		if (entry)
+		    mesh_fast_tx_entry_free(cache, entry);
+		spin_unlock_bh(&cache->walk_lock);
+		return NULL;
+	}
+
+	mesh_path_refresh(sdata, entry->mpath, NULL);
+	if (entry->mppath)
+		entry->mppath->exp_time = jiffies;
+	entry->timestamp = jiffies;
+
+	return entry;
+}
+
+void mesh_fast_tx_cache(struct ieee80211_sub_if_data *sdata,
+			struct sk_buff *skb, struct mesh_path *mpath)
+{
+	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+	struct ieee80211_mesh_fast_tx *entry, *prev;
+	struct ieee80211_mesh_fast_tx build = {};
+	struct ieee80211s_hdr *meshhdr;
+	struct mesh_tx_cache *cache;
+	struct ieee80211_key *key;
+	struct mesh_path *mppath;
+	struct sta_info *sta;
+	u8 *qc;
+
+	if (sdata->noack_map ||
+	    !ieee80211_is_data_qos(hdr->frame_control))
+		return;
+
+	build.fast_tx.hdr_len = ieee80211_hdrlen(hdr->frame_control);
+	meshhdr = (struct ieee80211s_hdr *)(skb->data + build.fast_tx.hdr_len);
+	build.hdrlen = ieee80211_get_mesh_hdrlen(meshhdr);
+
+	cache = &sdata->u.mesh.tx_cache;
+	if (atomic_read(&cache->rht.nelems) >= MESH_FAST_TX_CACHE_MAX_SIZE)
+		return;
+
+	sta = rcu_dereference(mpath->next_hop);
+	if (!sta)
+		return;
+
+	if ((meshhdr->flags & MESH_FLAGS_AE) == MESH_FLAGS_AE_A5_A6) {
+		/* This is required to keep the mppath alive */
+		mppath = mpp_path_lookup(sdata, meshhdr->eaddr1);
+		if (!mppath)
+			return;
+		build.mppath = mppath;
+	} else if (ieee80211_has_a4(hdr->frame_control)) {
+		mppath = mpath;
+	} else {
+		return;
+	}
+
+	/* rate limit, in case fast xmit can't be enabled */
+	if (mppath->fast_tx_check == jiffies)
+		return;
+
+	mppath->fast_tx_check = jiffies;
+
+	/*
+	 * Same use of the sta lock as in ieee80211_check_fast_xmit, in order
+	 * to protect against concurrent sta key updates.
+	 */
+	spin_lock_bh(&sta->lock);
+	key = rcu_access_pointer(sta->ptk[sta->ptk_idx]);
+	if (!key)
+		key = rcu_access_pointer(sdata->default_unicast_key);
+	build.fast_tx.key = key;
+
+	if (key) {
+		bool gen_iv, iv_spc;
+
+		gen_iv = key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV;
+		iv_spc = key->conf.flags & IEEE80211_KEY_FLAG_PUT_IV_SPACE;
+
+		if (!(key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE) ||
+		    (key->flags & KEY_FLAG_TAINTED))
+			goto unlock_sta;
+
+		switch (key->conf.cipher) {
+		case WLAN_CIPHER_SUITE_CCMP:
+		case WLAN_CIPHER_SUITE_CCMP_256:
+			if (gen_iv)
+				build.fast_tx.pn_offs = build.fast_tx.hdr_len;
+			if (gen_iv || iv_spc)
+				build.fast_tx.hdr_len += IEEE80211_CCMP_HDR_LEN;
+			break;
+		case WLAN_CIPHER_SUITE_GCMP:
+		case WLAN_CIPHER_SUITE_GCMP_256:
+			if (gen_iv)
+				build.fast_tx.pn_offs = build.fast_tx.hdr_len;
+			if (gen_iv || iv_spc)
+				build.fast_tx.hdr_len += IEEE80211_GCMP_HDR_LEN;
+			break;
+		default:
+			goto unlock_sta;
+		}
+	}
+
+	memcpy(build.addr_key, mppath->dst, ETH_ALEN);
+	build.timestamp = jiffies;
+	build.fast_tx.band = info->band;
+	build.fast_tx.da_offs = offsetof(struct ieee80211_hdr, addr3);
+	build.fast_tx.sa_offs = offsetof(struct ieee80211_hdr, addr4);
+	build.mpath = mpath;
+	memcpy(build.hdr, meshhdr, build.hdrlen);
+	memcpy(build.hdr + build.hdrlen, rfc1042_header, sizeof(rfc1042_header));
+	build.hdrlen += sizeof(rfc1042_header);
+	memcpy(build.fast_tx.hdr, hdr, build.fast_tx.hdr_len);
+
+	hdr = (struct ieee80211_hdr *)build.fast_tx.hdr;
+	if (build.fast_tx.key)
+		hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+
+	qc = ieee80211_get_qos_ctl(hdr);
+	qc[1] |= IEEE80211_QOS_CTL_MESH_CONTROL_PRESENT >> 8;
+
+	entry = kmemdup(&build, sizeof(build), GFP_ATOMIC);
+	if (!entry)
+		goto unlock_sta;
+
+	spin_lock(&cache->walk_lock);
+	prev = rhashtable_lookup_get_insert_fast(&cache->rht,
+						 &entry->rhash,
+						 fast_tx_rht_params);
+	if (unlikely(IS_ERR(prev))) {
+		kfree(entry);
+		goto unlock_cache;
+	}
+
+	/*
+	 * replace any previous entry in the hash table, in case we're
+	 * replacing it with a different type (e.g. mpath -> mpp)
+	 */
+	if (unlikely(prev)) {
+		rhashtable_replace_fast(&cache->rht, &prev->rhash,
+					&entry->rhash, fast_tx_rht_params);
+		hlist_del_rcu(&prev->walk_list);
+		kfree_rcu(prev, fast_tx.rcu_head);
+	}
+
+	hlist_add_head(&entry->walk_list, &cache->walk_head);
+
+unlock_cache:
+	spin_unlock(&cache->walk_lock);
+unlock_sta:
+	spin_unlock_bh(&sta->lock);
+}
+
+void mesh_fast_tx_gc(struct ieee80211_sub_if_data *sdata)
+{
+	unsigned long timeout = msecs_to_jiffies(MESH_FAST_TX_CACHE_TIMEOUT);
+	struct mesh_tx_cache *cache;
+	struct ieee80211_mesh_fast_tx *entry;
+	struct hlist_node *n;
+
+	cache = &sdata->u.mesh.tx_cache;
+	if (atomic_read(&cache->rht.nelems) < MESH_FAST_TX_CACHE_THRESHOLD_SIZE)
+		return;
+
+	spin_lock_bh(&cache->walk_lock);
+	hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
+		if (!time_is_after_jiffies(entry->timestamp + timeout))
+			mesh_fast_tx_entry_free(cache, entry);
+	spin_unlock_bh(&cache->walk_lock);
+}
+
+void mesh_fast_tx_flush_mpath(struct mesh_path *mpath)
+{
+	struct ieee80211_sub_if_data *sdata = mpath->sdata;
+	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
+	struct ieee80211_mesh_fast_tx *entry;
+	struct hlist_node *n;
+
+	cache = &sdata->u.mesh.tx_cache;
+	spin_lock_bh(&cache->walk_lock);
+	hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
+		if (entry->mpath == mpath)
+			mesh_fast_tx_entry_free(cache, entry);
+	spin_unlock_bh(&cache->walk_lock);
+}
+
+void mesh_fast_tx_flush_sta(struct ieee80211_sub_if_data *sdata,
+			    struct sta_info *sta)
+{
+	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
+	struct ieee80211_mesh_fast_tx *entry;
+	struct hlist_node *n;
+
+	cache = &sdata->u.mesh.tx_cache;
+	spin_lock_bh(&cache->walk_lock);
+	hlist_for_each_entry_safe(entry, n, &cache->walk_head, walk_list)
+		if (rcu_access_pointer(entry->mpath->next_hop) == sta)
+			mesh_fast_tx_entry_free(cache, entry);
+	spin_unlock_bh(&cache->walk_lock);
+}
+
+void mesh_fast_tx_flush_addr(struct ieee80211_sub_if_data *sdata,
+			     const u8 *addr)
+{
+	struct mesh_tx_cache *cache = &sdata->u.mesh.tx_cache;
+	struct ieee80211_mesh_fast_tx *entry;
+
+	cache = &sdata->u.mesh.tx_cache;
+	spin_lock_bh(&cache->walk_lock);
+	entry = rhashtable_lookup(&cache->rht, addr, fast_tx_rht_params);
+	if (entry)
+		mesh_fast_tx_entry_free(cache, entry);
+	spin_unlock_bh(&cache->walk_lock);
+}
+
 /**
  * mesh_path_add - allocate and add a new path to the mesh path table
  * @dst: destination address of the path (ETH_ALEN length)
@@ -464,6 +737,8 @@ int mpp_path_add(struct ieee80211_sub_if_data *sdata,
 
 	if (ret)
 		kfree(new_mpath);
+	else
+		mesh_fast_tx_flush_addr(sdata, dst);
 
 	sdata->u.mesh.mpp_paths_generation++;
 	return ret;
@@ -523,6 +798,10 @@ static void __mesh_path_del(struct mesh_table *tbl, struct mesh_path *mpath)
 {
 	hlist_del_rcu(&mpath->walk_list);
 	rhashtable_remove_fast(&tbl->rhead, &mpath->rhash, mesh_rht_params);
+	if (tbl == &mpath->sdata->u.mesh.mpp_paths)
+		mesh_fast_tx_flush_addr(mpath->sdata, mpath->dst);
+	else
+		mesh_fast_tx_flush_mpath(mpath);
 	mesh_path_free_rcu(tbl, mpath);
 }
 
@@ -747,6 +1026,7 @@ void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
 	mpath->exp_time = 0;
 	mpath->flags = MESH_PATH_FIXED | MESH_PATH_SN_VALID;
 	mesh_path_activate(mpath);
+	mesh_fast_tx_flush_mpath(mpath);
 	spin_unlock_bh(&mpath->state_lock);
 	ewma_mesh_fail_avg_init(&next_hop->mesh->fail_avg);
 	/* init it at a low value - 0 start is tricky */
@@ -758,6 +1038,7 @@ void mesh_pathtbl_init(struct ieee80211_sub_if_data *sdata)
 {
 	mesh_table_init(&sdata->u.mesh.mesh_paths);
 	mesh_table_init(&sdata->u.mesh.mpp_paths);
+	mesh_fast_tx_init(sdata);
 }
 
 static
@@ -785,6 +1066,7 @@ void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
 
 void mesh_pathtbl_unregister(struct ieee80211_sub_if_data *sdata)
 {
+	mesh_fast_tx_deinit(sdata);
 	mesh_table_free(&sdata->u.mesh.mesh_paths);
 	mesh_table_free(&sdata->u.mesh.mpp_paths);
 }