1 files changed, 442 insertions, 179 deletions

diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index 0d2faacc3e8..cf032a8db9d 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -14,6 +14,7 @@
 #include <linux/spinlock.h>
 #include <linux/string.h>
 #include <net/mac80211.h>
+#include "wme.h"
 #include "ieee80211_i.h"
 #include "mesh.h"
 
@@ -23,9 +24,12 @@
 /* Keep the mean chain length below this constant */
 #define MEAN_CHAIN_LEN		2
 
-#define MPATH_EXPIRED(mpath) ((mpath->flags & MESH_PATH_ACTIVE) && \
-				time_after(jiffies, mpath->exp_time) && \
-				!(mpath->flags & MESH_PATH_FIXED))
+static inline bool mpath_expired(struct mesh_path *mpath)
+{
+	return (mpath->flags & MESH_PATH_ACTIVE) &&
+	       time_after(jiffies, mpath->exp_time) &&
+	       !(mpath->flags & MESH_PATH_FIXED);
+}
 
 struct mpath_node {
 	struct hlist_node list;
@@ -42,8 +46,10 @@ static struct mesh_table __rcu *mpp_paths; /* Store paths for MPP&MAP */
 int mesh_paths_generation;
 
 /* This lock will have the grow table function as writer and add / delete nodes
- * as readers. When reading the table (i.e. doing lookups) we are well protected
- * by RCU
+ * as readers. RCU provides sufficient protection only when reading the table
+ * (i.e. doing lookups).  Adding or adding or removing nodes requires we take
+ * the read lock or we risk operating on an old table.  The write lock is only
+ * needed when modifying the number of buckets a table.
  */
 static DEFINE_RWLOCK(pathtbl_resize_lock);
 
@@ -66,9 +72,9 @@ static inline struct mesh_table *resize_dereference_mpp_paths(void)
  * it's used twice. So it is illegal to do
  *	for_each_mesh_entry(rcu_dereference(...), ...)
  */
-#define for_each_mesh_entry(tbl, p, node, i) \
+#define for_each_mesh_entry(tbl, node, i) \
 	for (i = 0; i <= tbl->hash_mask; i++) \
-		hlist_for_each_entry_rcu(node, p, &tbl->hash_buckets[i], list)
+		hlist_for_each_entry_rcu(node, &tbl->hash_buckets[i], list)
 
 
 static struct mesh_table *mesh_table_alloc(int size_order)
@@ -103,6 +109,7 @@ static struct mesh_table *mesh_table_alloc(int size_order)
 			sizeof(newtbl->hash_rnd));
 	for (i = 0; i <= newtbl->hash_mask; i++)
 		spin_lock_init(&newtbl->hashwlock[i]);
+	spin_lock_init(&newtbl->gates_lock);
 
 	return newtbl;
 }
@@ -118,6 +125,7 @@ static void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
 {
 	struct hlist_head *mesh_hash;
 	struct hlist_node *p, *q;
+	struct mpath_node *gate;
 	int i;
 
 	mesh_hash = tbl->hash_buckets;
@@ -129,6 +137,17 @@ static void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
 		}
 		spin_unlock_bh(&tbl->hashwlock[i]);
 	}
+	if (free_leafs) {
+		spin_lock_bh(&tbl->gates_lock);
+		hlist_for_each_entry_safe(gate, q,
+					 tbl->known_gates, list) {
+			hlist_del(&gate->list);
+			kfree(gate);
+		}
+		kfree(tbl->known_gates);
+		spin_unlock_bh(&tbl->gates_lock);
+	}
+
 	__mesh_table_free(tbl);
 }
 
@@ -146,6 +165,7 @@ static int mesh_table_grow(struct mesh_table *oldtbl,
 	newtbl->free_node = oldtbl->free_node;
 	newtbl->mean_chain_len = oldtbl->mean_chain_len;
 	newtbl->copy_node = oldtbl->copy_node;
+	newtbl->known_gates = oldtbl->known_gates;
 	atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries));
 
 	oldhash = oldtbl->hash_buckets;
@@ -164,12 +184,12 @@ errcopy:
 	return -ENOMEM;
 }
 
-static u32 mesh_table_hash(u8 *addr, struct ieee80211_sub_if_data *sdata,
+static u32 mesh_table_hash(const u8 *addr, struct ieee80211_sub_if_data *sdata,
 			   struct mesh_table *tbl)
 {
 	/* Use last four bytes of hw addr and interface index as hash index */
-	return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex, tbl->hash_rnd)
-		& tbl->hash_mask;
+	return jhash_2words(*(u32 *)(addr+2), sdata->dev->ifindex,
+			    tbl->hash_rnd) & tbl->hash_mask;
 }
 
 
@@ -186,81 +206,146 @@ void mesh_path_assign_nexthop(struct mesh_path *mpath, struct sta_info *sta)
 {
 	struct sk_buff *skb;
 	struct ieee80211_hdr *hdr;
-	struct sk_buff_head tmpq;
 	unsigned long flags;
 
 	rcu_assign_pointer(mpath->next_hop, sta);
 
-	__skb_queue_head_init(&tmpq);
-
 	spin_lock_irqsave(&mpath->frame_queue.lock, flags);
-
-	while ((skb = __skb_dequeue(&mpath->frame_queue)) != NULL) {
+	skb_queue_walk(&mpath->frame_queue, skb) {
 		hdr = (struct ieee80211_hdr *) skb->data;
 		memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
-		__skb_queue_tail(&tmpq, skb);
+		memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
+		ieee80211_mps_set_frame_flags(sta->sdata, sta, hdr);
 	}
 
-	skb_queue_splice(&tmpq, &mpath->frame_queue);
 	spin_unlock_irqrestore(&mpath->frame_queue.lock, flags);
 }
 
+static void prepare_for_gate(struct sk_buff *skb, char *dst_addr,
+			     struct mesh_path *gate_mpath)
+{
+	struct ieee80211_hdr *hdr;
+	struct ieee80211s_hdr *mshdr;
+	int mesh_hdrlen, hdrlen;
+	char *next_hop;
+
+	hdr = (struct ieee80211_hdr *) skb->data;
+	hdrlen = ieee80211_hdrlen(hdr->frame_control);
+	mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
+
+	if (!(mshdr->flags & MESH_FLAGS_AE)) {
+		/* size of the fixed part of the mesh header */
+		mesh_hdrlen = 6;
+
+		/* make room for the two extended addresses */
+		skb_push(skb, 2 * ETH_ALEN);
+		memmove(skb->data, hdr, hdrlen + mesh_hdrlen);
+
+		hdr = (struct ieee80211_hdr *) skb->data;
+
+		/* we preserve the previous mesh header and only add
+		 * the new addreses */
+		mshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen);
+		mshdr->flags = MESH_FLAGS_AE_A5_A6;
+		memcpy(mshdr->eaddr1, hdr->addr3, ETH_ALEN);
+		memcpy(mshdr->eaddr2, hdr->addr4, ETH_ALEN);
+	}
+
+	/* update next hop */
+	hdr = (struct ieee80211_hdr *) skb->data;
+	rcu_read_lock();
+	next_hop = rcu_dereference(gate_mpath->next_hop)->sta.addr;
+	memcpy(hdr->addr1, next_hop, ETH_ALEN);
+	rcu_read_unlock();
+	memcpy(hdr->addr2, gate_mpath->sdata->vif.addr, ETH_ALEN);
+	memcpy(hdr->addr3, dst_addr, ETH_ALEN);
+}
 
 /**
- * mesh_path_lookup - look up a path in the mesh path table
- * @dst: hardware address (ETH_ALEN length) of destination
- * @sdata: local subif
  *
- * Returns: pointer to the mesh path structure, or NULL if not found
+ * mesh_path_move_to_queue - Move or copy frames from one mpath queue to another
  *
- * Locking: must be called within a read rcu section.
+ * This function is used to transfer or copy frames from an unresolved mpath to
+ * a gate mpath.  The function also adds the Address Extension field and
+ * updates the next hop.
+ *
+ * If a frame already has an Address Extension field, only the next hop and
+ * destination addresses are updated.
+ *
+ * The gate mpath must be an active mpath with a valid mpath->next_hop.
+ *
+ * @mpath: An active mpath the frames will be sent to (i.e. the gate)
+ * @from_mpath: The failed mpath
+ * @copy: When true, copy all the frames to the new mpath queue.  When false,
+ * move them.
  */
-struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
+				    struct mesh_path *from_mpath,
+				    bool copy)
 {
-	struct mesh_path *mpath;
-	struct hlist_node *n;
-	struct hlist_head *bucket;
-	struct mesh_table *tbl;
-	struct mpath_node *node;
+	struct sk_buff *skb, *fskb, *tmp;
+	struct sk_buff_head failq;
+	unsigned long flags;
 
-	tbl = rcu_dereference(mesh_paths);
+	if (WARN_ON(gate_mpath == from_mpath))
+		return;
+	if (WARN_ON(!gate_mpath->next_hop))
+		return;
 
-	bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
-	hlist_for_each_entry_rcu(node, n, bucket, list) {
-		mpath = node->mpath;
-		if (mpath->sdata == sdata &&
-				memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
-			if (MPATH_EXPIRED(mpath)) {
-				spin_lock_bh(&mpath->state_lock);
-				if (MPATH_EXPIRED(mpath))
-					mpath->flags &= ~MESH_PATH_ACTIVE;
-				spin_unlock_bh(&mpath->state_lock);
-			}
-			return mpath;
+	__skb_queue_head_init(&failq);
+
+	spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
+	skb_queue_splice_init(&from_mpath->frame_queue, &failq);
+	spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
+
+	skb_queue_walk_safe(&failq, fskb, tmp) {
+		if (skb_queue_len(&gate_mpath->frame_queue) >=
+				  MESH_FRAME_QUEUE_LEN) {
+			mpath_dbg(gate_mpath->sdata, "mpath queue full!\n");
+			break;
 		}
+
+		skb = skb_copy(fskb, GFP_ATOMIC);
+		if (WARN_ON(!skb))
+			break;
+
+		prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
+		skb_queue_tail(&gate_mpath->frame_queue, skb);
+
+		if (copy)
+			continue;
+
+		__skb_unlink(fskb, &failq);
+		kfree_skb(fskb);
 	}
-	return NULL;
+
+	mpath_dbg(gate_mpath->sdata, "Mpath queue for gate %pM has %d frames\n",
+		  gate_mpath->dst, skb_queue_len(&gate_mpath->frame_queue));
+
+	if (!copy)
+		return;
+
+	spin_lock_irqsave(&from_mpath->frame_queue.lock, flags);
+	skb_queue_splice(&failq, &from_mpath->frame_queue);
+	spin_unlock_irqrestore(&from_mpath->frame_queue.lock, flags);
 }
 
-struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+
+static struct mesh_path *mpath_lookup(struct mesh_table *tbl, const u8 *dst,
+				      struct ieee80211_sub_if_data *sdata)
 {
 	struct mesh_path *mpath;
-	struct hlist_node *n;
 	struct hlist_head *bucket;
-	struct mesh_table *tbl;
 	struct mpath_node *node;
 
-	tbl = rcu_dereference(mpp_paths);
-
 	bucket = &tbl->hash_buckets[mesh_table_hash(dst, sdata, tbl)];
-	hlist_for_each_entry_rcu(node, n, bucket, list) {
+	hlist_for_each_entry_rcu(node, bucket, list) {
 		mpath = node->mpath;
 		if (mpath->sdata == sdata &&
-		    memcmp(dst, mpath->dst, ETH_ALEN) == 0) {
-			if (MPATH_EXPIRED(mpath)) {
+		    ether_addr_equal(dst, mpath->dst)) {
+			if (mpath_expired(mpath)) {
 				spin_lock_bh(&mpath->state_lock);
-				if (MPATH_EXPIRED(mpath))
-					mpath->flags &= ~MESH_PATH_ACTIVE;
+				mpath->flags &= ~MESH_PATH_ACTIVE;
 				spin_unlock_bh(&mpath->state_lock);
 			}
 			return mpath;
@@ -269,6 +354,27 @@ struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
 	return NULL;
 }
 
+/**
+ * mesh_path_lookup - look up a path in the mesh path table
+ * @sdata: local subif
+ * @dst: hardware address (ETH_ALEN length) of destination
+ *
+ * Returns: pointer to the mesh path structure, or NULL if not found
+ *
+ * Locking: must be called within a read rcu section.
+ */
+struct mesh_path *
+mesh_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
+{
+	return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata);
+}
+
+struct mesh_path *
+mpp_path_lookup(struct ieee80211_sub_if_data *sdata, const u8 *dst)
+{
+	return mpath_lookup(rcu_dereference(mpp_paths), dst, sdata);
+}
+
 
 /**
  * mesh_path_lookup_by_idx - look up a path in the mesh path table by its index
@@ -279,22 +385,21 @@ struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
  *
  * Locking: must be called within a read rcu section.
  */
-struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data *sdata)
+struct mesh_path *
+mesh_path_lookup_by_idx(struct ieee80211_sub_if_data *sdata, int idx)
 {
 	struct mesh_table *tbl = rcu_dereference(mesh_paths);
 	struct mpath_node *node;
-	struct hlist_node *p;
 	int i;
 	int j = 0;
 
-	for_each_mesh_entry(tbl, p, node, i) {
+	for_each_mesh_entry(tbl, node, i) {
 		if (sdata && node->mpath->sdata != sdata)
 			continue;
 		if (j++ == idx) {
-			if (MPATH_EXPIRED(node->mpath)) {
+			if (mpath_expired(node->mpath)) {
 				spin_lock_bh(&node->mpath->state_lock);
-				if (MPATH_EXPIRED(node->mpath))
-					node->mpath->flags &= ~MESH_PATH_ACTIVE;
+				node->mpath->flags &= ~MESH_PATH_ACTIVE;
 				spin_unlock_bh(&node->mpath->state_lock);
 			}
 			return node->mpath;
@@ -305,15 +410,93 @@ struct mesh_path *mesh_path_lookup_by_idx(int idx, struct ieee80211_sub_if_data
 }
 
 /**
+ * mesh_path_add_gate - add the given mpath to a mesh gate to our path table
+ * @mpath: gate path to add to table
+ */
+int mesh_path_add_gate(struct mesh_path *mpath)
+{
+	struct mesh_table *tbl;
+	struct mpath_node *gate, *new_gate;
+	int err;
+
+	rcu_read_lock();
+	tbl = rcu_dereference(mesh_paths);
+
+	hlist_for_each_entry_rcu(gate, tbl->known_gates, list)
+		if (gate->mpath == mpath) {
+			err = -EEXIST;
+			goto err_rcu;
+		}
+
+	new_gate = kzalloc(sizeof(struct mpath_node), GFP_ATOMIC);
+	if (!new_gate) {
+		err = -ENOMEM;
+		goto err_rcu;
+	}
+
+	mpath->is_gate = true;
+	mpath->sdata->u.mesh.num_gates++;
+	new_gate->mpath = mpath;
+	spin_lock_bh(&tbl->gates_lock);
+	hlist_add_head_rcu(&new_gate->list, tbl->known_gates);
+	spin_unlock_bh(&tbl->gates_lock);
+	mpath_dbg(mpath->sdata,
+		  "Mesh path: Recorded new gate: %pM. %d known gates\n",
+		  mpath->dst, mpath->sdata->u.mesh.num_gates);
+	err = 0;
+err_rcu:
+	rcu_read_unlock();
+	return err;
+}
+
+/**
+ * mesh_gate_del - remove a mesh gate from the list of known gates
+ * @tbl: table which holds our list of known gates
+ * @mpath: gate mpath
+ *
+ * Locking: must be called inside rcu_read_lock() section
+ */
+static void mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
+{
+	struct mpath_node *gate;
+	struct hlist_node *q;
+
+	hlist_for_each_entry_safe(gate, q, tbl->known_gates, list) {
+		if (gate->mpath != mpath)
+			continue;
+		spin_lock_bh(&tbl->gates_lock);
+		hlist_del_rcu(&gate->list);
+		kfree_rcu(gate, rcu);
+		spin_unlock_bh(&tbl->gates_lock);
+		mpath->sdata->u.mesh.num_gates--;
+		mpath->is_gate = false;
+		mpath_dbg(mpath->sdata,
+			  "Mesh path: Deleted gate: %pM. %d known gates\n",
+			  mpath->dst, mpath->sdata->u.mesh.num_gates);
+		break;
+	}
+}
+
+/**
+ * mesh_gate_num - number of gates known to this interface
+ * @sdata: subif data
+ */
+int mesh_gate_num(struct ieee80211_sub_if_data *sdata)
+{
+	return sdata->u.mesh.num_gates;
+}
+
+/**
  * mesh_path_add - allocate and add a new path to the mesh path table
- * @addr: destination address of the path (ETH_ALEN length)
+ * @dst: destination address of the path (ETH_ALEN length)
  * @sdata: local subif
  *
  * Returns: 0 on success
  *
  * State: the initial state of the new path is set to 0
  */
-int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
+struct mesh_path *mesh_path_add(struct ieee80211_sub_if_data *sdata,
+				const u8 *dst)
 {
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct ieee80211_local *local = sdata->local;
@@ -321,20 +504,34 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
 	struct mesh_path *mpath, *new_mpath;
 	struct mpath_node *node, *new_node;
 	struct hlist_head *bucket;
-	struct hlist_node *n;
 	int grow = 0;
-	int err = 0;
+	int err;
 	u32 hash_idx;
 
-	if (memcmp(dst, sdata->vif.addr, ETH_ALEN) == 0)
+	if (ether_addr_equal(dst, sdata->vif.addr))
 		/* never add ourselves as neighbours */
-		return -ENOTSUPP;
+		return ERR_PTR(-ENOTSUPP);
 
 	if (is_multicast_ether_addr(dst))
-		return -ENOTSUPP;
+		return ERR_PTR(-ENOTSUPP);
 
 	if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
-		return -ENOSPC;
+		return ERR_PTR(-ENOSPC);
+
+	read_lock_bh(&pathtbl_resize_lock);
+	tbl = resize_dereference_mesh_paths();
+
+	hash_idx = mesh_table_hash(dst, sdata, tbl);
+	bucket = &tbl->hash_buckets[hash_idx];
+
+	spin_lock(&tbl->hashwlock[hash_idx]);
+
+	hlist_for_each_entry(node, bucket, list) {
+		mpath = node->mpath;
+		if (mpath->sdata == sdata &&
+		    ether_addr_equal(dst, mpath->dst))
+			goto found;
+	}
 
 	err = -ENOMEM;
 	new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
@@ -345,8 +542,9 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
 	if (!new_node)
 		goto err_node_alloc;
 
-	read_lock_bh(&pathtbl_resize_lock);
 	memcpy(new_mpath->dst, dst, ETH_ALEN);
+	eth_broadcast_addr(new_mpath->rann_snd_addr);
+	new_mpath->is_root = false;
 	new_mpath->sdata = sdata;
 	new_mpath->flags = 0;
 	skb_queue_head_init(&new_mpath->frame_queue);
@@ -357,20 +555,6 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
 	spin_lock_init(&new_mpath->state_lock);
 	init_timer(&new_mpath->timer);
 
-	tbl = resize_dereference_mesh_paths();
-
-	hash_idx = mesh_table_hash(dst, sdata, tbl);
-	bucket = &tbl->hash_buckets[hash_idx];
-
-	spin_lock_bh(&tbl->hashwlock[hash_idx]);
-
-	err = -EEXIST;
-	hlist_for_each_entry(node, n, bucket, list) {
-		mpath = node->mpath;
-		if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
-			goto err_exists;
-	}
-
 	hlist_add_head_rcu(&new_node->list, bucket);
 	if (atomic_inc_return(&tbl->entries) >=
 	    tbl->mean_chain_len * (tbl->hash_mask + 1))
@@ -378,23 +562,23 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
 
 	mesh_paths_generation++;
 
-	spin_unlock_bh(&tbl->hashwlock[hash_idx]);
-	read_unlock_bh(&pathtbl_resize_lock);
 	if (grow) {
 		set_bit(MESH_WORK_GROW_MPATH_TABLE,  &ifmsh->wrkq_flags);
 		ieee80211_queue_work(&local->hw, &sdata->work);
 	}
-	return 0;
-
-err_exists:
-	spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+	mpath = new_mpath;
+found:
+	spin_unlock(&tbl->hashwlock[hash_idx]);
 	read_unlock_bh(&pathtbl_resize_lock);
-	kfree(new_node);
+	return mpath;
+
 err_node_alloc:
 	kfree(new_mpath);
 err_path_alloc:
 	atomic_dec(&sdata->u.mesh.mpaths);
-	return err;
+	spin_unlock(&tbl->hashwlock[hash_idx]);
+	read_unlock_bh(&pathtbl_resize_lock);
+	return ERR_PTR(err);
 }
 
 static void mesh_table_free_rcu(struct rcu_head *rcu)
@@ -445,7 +629,8 @@ void mesh_mpp_table_grow(void)
 	write_unlock_bh(&pathtbl_resize_lock);
 }
 
-int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
+int mpp_path_add(struct ieee80211_sub_if_data *sdata,
+		 const u8 *dst, const u8 *mpp)
 {
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	struct ieee80211_local *local = sdata->local;
@@ -453,12 +638,11 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
 	struct mesh_path *mpath, *new_mpath;
 	struct mpath_node *node, *new_node;
 	struct hlist_head *bucket;
-	struct hlist_node *n;
 	int grow = 0;
 	int err = 0;
 	u32 hash_idx;
 
-	if (memcmp(dst, sdata->vif.addr, ETH_ALEN) == 0)
+	if (ether_addr_equal(dst, sdata->vif.addr))
 		/* never add ourselves as neighbours */
 		return -ENOTSUPP;
 
@@ -481,6 +665,7 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
 	new_mpath->flags = 0;
 	skb_queue_head_init(&new_mpath->frame_queue);
 	new_node->mpath = new_mpath;
+	init_timer(&new_mpath->timer);
 	new_mpath->exp_time = jiffies;
 	spin_lock_init(&new_mpath->state_lock);
 
@@ -489,12 +674,13 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
 	hash_idx = mesh_table_hash(dst, sdata, tbl);
 	bucket = &tbl->hash_buckets[hash_idx];
 
-	spin_lock_bh(&tbl->hashwlock[hash_idx]);
+	spin_lock(&tbl->hashwlock[hash_idx]);
 
 	err = -EEXIST;
-	hlist_for_each_entry(node, n, bucket, list) {
+	hlist_for_each_entry(node, bucket, list) {
 		mpath = node->mpath;
-		if (mpath->sdata == sdata && memcmp(dst, mpath->dst, ETH_ALEN) == 0)
+		if (mpath->sdata == sdata &&
+		    ether_addr_equal(dst, mpath->dst))
 			goto err_exists;
 	}
 
@@ -503,7 +689,7 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
 	    tbl->mean_chain_len * (tbl->hash_mask + 1))
 		grow = 1;
 
-	spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+	spin_unlock(&tbl->hashwlock[hash_idx]);
 	read_unlock_bh(&pathtbl_resize_lock);
 	if (grow) {
 		set_bit(MESH_WORK_GROW_MPP_TABLE,  &ifmsh->wrkq_flags);
@@ -512,7 +698,7 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
 	return 0;
 
 err_exists:
-	spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+	spin_unlock(&tbl->hashwlock[hash_idx]);
 	read_unlock_bh(&pathtbl_resize_lock);
 	kfree(new_node);
 err_node_alloc:
@@ -536,35 +722,59 @@ void mesh_plink_broken(struct sta_info *sta)
 	static const u8 bcast[ETH_ALEN] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
 	struct mesh_path *mpath;
 	struct mpath_node *node;
-	struct hlist_node *p;
 	struct ieee80211_sub_if_data *sdata = sta->sdata;
 	int i;
 
 	rcu_read_lock();
 	tbl = rcu_dereference(mesh_paths);
-	for_each_mesh_entry(tbl, p, node, i) {
+	for_each_mesh_entry(tbl, node, i) {
 		mpath = node->mpath;
-		spin_lock_bh(&mpath->state_lock);
 		if (rcu_dereference(mpath->next_hop) == sta &&
 		    mpath->flags & MESH_PATH_ACTIVE &&
 		    !(mpath->flags & MESH_PATH_FIXED)) {
+			spin_lock_bh(&mpath->state_lock);
 			mpath->flags &= ~MESH_PATH_ACTIVE;
 			++mpath->sn;
 			spin_unlock_bh(&mpath->state_lock);
-			mesh_path_error_tx(sdata->u.mesh.mshcfg.element_ttl,
-					mpath->dst, cpu_to_le32(mpath->sn),
-					cpu_to_le16(PERR_RCODE_DEST_UNREACH),
-					bcast, sdata);
-		} else
-		spin_unlock_bh(&mpath->state_lock);
+			mesh_path_error_tx(sdata,
+				sdata->u.mesh.mshcfg.element_ttl,
+				mpath->dst, mpath->sn,
+				WLAN_REASON_MESH_PATH_DEST_UNREACHABLE, bcast);
+		}
 	}
 	rcu_read_unlock();
 }
 
+static void mesh_path_node_reclaim(struct rcu_head *rp)
+{
+	struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
+	struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
+
+	del_timer_sync(&node->mpath->timer);
+	atomic_dec(&sdata->u.mesh.mpaths);
+	kfree(node->mpath);
+	kfree(node);
+}
+
+/* needs to be called with the corresponding hashwlock taken */
+static void __mesh_path_del(struct mesh_table *tbl, struct mpath_node *node)
+{
+	struct mesh_path *mpath;
+	mpath = node->mpath;
+	spin_lock(&mpath->state_lock);
+	mpath->flags |= MESH_PATH_RESOLVING;
+	if (mpath->is_gate)
+		mesh_gate_del(tbl, mpath);
+	hlist_del_rcu(&node->list);
+	call_rcu(&node->rcu, mesh_path_node_reclaim);
+	spin_unlock(&mpath->state_lock);
+	atomic_dec(&tbl->entries);
+}
+
 /**
  * mesh_path_flush_by_nexthop - Deletes mesh paths if their next hop matches
  *
- * @sta - mesh peer to match
+ * @sta: mesh peer to match
  *
  * RCU notes: this function is called when a mesh plink transitions from
  * PLINK_ESTAB to any other state, since PLINK_ESTAB state is the only one that
@@ -577,46 +787,61 @@ void mesh_path_flush_by_nexthop(struct sta_info *sta)
 	struct mesh_table *tbl;
 	struct mesh_path *mpath;
 	struct mpath_node *node;
-	struct hlist_node *p;
 	int i;
 
 	rcu_read_lock();
-	tbl = rcu_dereference(mesh_paths);
-	for_each_mesh_entry(tbl, p, node, i) {
+	read_lock_bh(&pathtbl_resize_lock);
+	tbl = resize_dereference_mesh_paths();
+	for_each_mesh_entry(tbl, node, i) {
 		mpath = node->mpath;
-		if (rcu_dereference(mpath->next_hop) == sta)
-			mesh_path_del(mpath->dst, mpath->sdata);
+		if (rcu_dereference(mpath->next_hop) == sta) {
+			spin_lock(&tbl->hashwlock[i]);
+			__mesh_path_del(tbl, node);
+			spin_unlock(&tbl->hashwlock[i]);
+		}
 	}
+	read_unlock_bh(&pathtbl_resize_lock);
 	rcu_read_unlock();
 }
 
-void mesh_path_flush(struct ieee80211_sub_if_data *sdata)
+static void table_flush_by_iface(struct mesh_table *tbl,
+				 struct ieee80211_sub_if_data *sdata)
 {
-	struct mesh_table *tbl;
 	struct mesh_path *mpath;
 	struct mpath_node *node;
-	struct hlist_node *p;
 	int i;
 
-	rcu_read_lock();
-	tbl = rcu_dereference(mesh_paths);
-	for_each_mesh_entry(tbl, p, node, i) {
+	WARN_ON(!rcu_read_lock_held());
+	for_each_mesh_entry(tbl, node, i) {
 		mpath = node->mpath;
-		if (mpath->sdata == sdata)
-			mesh_path_del(mpath->dst, mpath->sdata);
+		if (mpath->sdata != sdata)
+			continue;
+		spin_lock_bh(&tbl->hashwlock[i]);
+		__mesh_path_del(tbl, node);
+		spin_unlock_bh(&tbl->hashwlock[i]);
 	}
-	rcu_read_unlock();
 }
 
-static void mesh_path_node_reclaim(struct rcu_head *rp)
+/**
+ * mesh_path_flush_by_iface - Deletes all mesh paths associated with a given iface
+ *
+ * This function deletes both mesh paths as well as mesh portal paths.
+ *
+ * @sdata: interface data to match
+ *
+ */
+void mesh_path_flush_by_iface(struct ieee80211_sub_if_data *sdata)
 {
-	struct mpath_node *node = container_of(rp, struct mpath_node, rcu);
-	struct ieee80211_sub_if_data *sdata = node->mpath->sdata;
+	struct mesh_table *tbl;
 
-	del_timer_sync(&node->mpath->timer);
-	atomic_dec(&sdata->u.mesh.mpaths);
-	kfree(node->mpath);
-	kfree(node);
+	rcu_read_lock();
+	read_lock_bh(&pathtbl_resize_lock);
+	tbl = resize_dereference_mesh_paths();
+	table_flush_by_iface(tbl, sdata);
+	tbl = resize_dereference_mpp_paths();
+	table_flush_by_iface(tbl, sdata);
+	read_unlock_bh(&pathtbl_resize_lock);
+	rcu_read_unlock();
 }
 
 /**
@@ -627,13 +852,12 @@ static void mesh_path_node_reclaim(struct rcu_head *rp)
  *
  * Returns: 0 if successful
  */
-int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
+int mesh_path_del(struct ieee80211_sub_if_data *sdata, const u8 *addr)
 {
 	struct mesh_table *tbl;
 	struct mesh_path *mpath;
 	struct mpath_node *node;
 	struct hlist_head *bucket;
-	struct hlist_node *n;
 	int hash_idx;
 	int err = 0;
 
@@ -642,17 +866,12 @@ int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
 	hash_idx = mesh_table_hash(addr, sdata, tbl);
 	bucket = &tbl->hash_buckets[hash_idx];
 
-	spin_lock_bh(&tbl->hashwlock[hash_idx]);
-	hlist_for_each_entry(node, n, bucket, list) {
+	spin_lock(&tbl->hashwlock[hash_idx]);
+	hlist_for_each_entry(node, bucket, list) {
 		mpath = node->mpath;
 		if (mpath->sdata == sdata &&
-		    memcmp(addr, mpath->dst, ETH_ALEN) == 0) {
-			spin_lock_bh(&mpath->state_lock);
-			mpath->flags |= MESH_PATH_RESOLVING;
-			hlist_del_rcu(&node->list);
-			call_rcu(&node->rcu, mesh_path_node_reclaim);
-			atomic_dec(&tbl->entries);
-			spin_unlock_bh(&mpath->state_lock);
+		    ether_addr_equal(addr, mpath->dst)) {
+			__mesh_path_del(tbl, node);
 			goto enddel;
 		}
 	}
@@ -660,7 +879,7 @@ int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
 	err = -ENXIO;
 enddel:
 	mesh_paths_generation++;
-	spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+	spin_unlock(&tbl->hashwlock[hash_idx]);
 	read_unlock_bh(&pathtbl_resize_lock);
 	return err;
 }
@@ -681,38 +900,68 @@ void mesh_path_tx_pending(struct mesh_path *mpath)
 }
 
 /**
+ * mesh_path_send_to_gates - sends pending frames to all known mesh gates
+ *
+ * @mpath: mesh path whose queue will be emptied
+ *
+ * If there is only one gate, the frames are transferred from the failed mpath
+ * queue to that gate's queue.  If there are more than one gates, the frames
+ * are copied from each gate to the next.  After frames are copied, the
+ * mpath queues are emptied onto the transmission queue.
+ */
+int mesh_path_send_to_gates(struct mesh_path *mpath)
+{
+	struct ieee80211_sub_if_data *sdata = mpath->sdata;
+	struct mesh_table *tbl;
+	struct mesh_path *from_mpath = mpath;
+	struct mpath_node *gate = NULL;
+	bool copy = false;
+	struct hlist_head *known_gates;
+
+	rcu_read_lock();
+	tbl = rcu_dereference(mesh_paths);
+	known_gates = tbl->known_gates;
+	rcu_read_unlock();
+
+	if (!known_gates)
+		return -EHOSTUNREACH;
+
+	hlist_for_each_entry_rcu(gate, known_gates, list) {
+		if (gate->mpath->sdata != sdata)
+			continue;
+
+		if (gate->mpath->flags & MESH_PATH_ACTIVE) {
+			mpath_dbg(sdata, "Forwarding to %pM\n", gate->mpath->dst);
+			mesh_path_move_to_queue(gate->mpath, from_mpath, copy);
+			from_mpath = gate->mpath;
+			copy = true;
+		} else {
+			mpath_dbg(sdata,
+				  "Not forwarding %p (flags %#x)\n",
+				  gate->mpath, gate->mpath->flags);
+		}
+	}
+
+	hlist_for_each_entry_rcu(gate, known_gates, list)
+		if (gate->mpath->sdata == sdata) {
+			mpath_dbg(sdata, "Sending to %pM\n", gate->mpath->dst);
+			mesh_path_tx_pending(gate->mpath);
+		}
+
+	return (from_mpath == mpath) ? -EHOSTUNREACH : 0;
+}
+
+/**
  * mesh_path_discard_frame - discard a frame whose path could not be resolved
  *
  * @skb: frame to discard
  * @sdata: network subif the frame was to be sent through
  *
- * If the frame was being forwarded from another MP, a PERR frame will be sent
- * to the precursor.  The precursor's address (i.e. the previous hop) was saved
- * in addr1 of the frame-to-be-forwarded, and would only be overwritten once
- * the destination is successfully resolved.
- *
  * Locking: the function must me called within a rcu_read_lock region
  */
-void mesh_path_discard_frame(struct sk_buff *skb,
-			     struct ieee80211_sub_if_data *sdata)
+void mesh_path_discard_frame(struct ieee80211_sub_if_data *sdata,
+			     struct sk_buff *skb)
 {
-	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
-	struct mesh_path *mpath;
-	u32 sn = 0;
-
-	if (memcmp(hdr->addr4, sdata->vif.addr, ETH_ALEN) != 0) {
-		u8 *ra, *da;
-
-		da = hdr->addr3;
-		ra = hdr->addr1;
-		mpath = mesh_path_lookup(da, sdata);
-		if (mpath)
-			sn = ++mpath->sn;
-		mesh_path_error_tx(sdata->u.mesh.mshcfg.element_ttl, skb->data,
-				   cpu_to_le32(sn),
-				   cpu_to_le16(PERR_RCODE_NO_ROUTE), ra, sdata);
-	}
-
 	kfree_skb(skb);
 	sdata->u.mesh.mshstats.dropped_frames_no_route++;
 }
@@ -728,9 +977,8 @@ void mesh_path_flush_pending(struct mesh_path *mpath)
 {
 	struct sk_buff *skb;
 
-	while ((skb = skb_dequeue(&mpath->frame_queue)) &&
-			(mpath->flags & MESH_PATH_ACTIVE))
-		mesh_path_discard_frame(skb, mpath->sdata);
+	while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
+		mesh_path_discard_frame(mpath->sdata, skb);
 }
 
 /**
@@ -790,6 +1038,7 @@ static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
 int mesh_pathtbl_init(void)
 {
 	struct mesh_table *tbl_path, *tbl_mpp;
+	int ret;
 
 	tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
 	if (!tbl_path)
@@ -797,21 +1046,40 @@ int mesh_pathtbl_init(void)
 	tbl_path->free_node = &mesh_path_node_free;
 	tbl_path->copy_node = &mesh_path_node_copy;
 	tbl_path->mean_chain_len = MEAN_CHAIN_LEN;
+	tbl_path->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
+	if (!tbl_path->known_gates) {
+		ret = -ENOMEM;
+		goto free_path;
+	}
+	INIT_HLIST_HEAD(tbl_path->known_gates);
+
 
 	tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
 	if (!tbl_mpp) {
-		mesh_table_free(tbl_path, true);
-		return -ENOMEM;
+		ret = -ENOMEM;
+		goto free_path;
 	}
 	tbl_mpp->free_node = &mesh_path_node_free;
 	tbl_mpp->copy_node = &mesh_path_node_copy;
 	tbl_mpp->mean_chain_len = MEAN_CHAIN_LEN;
+	tbl_mpp->known_gates = kzalloc(sizeof(struct hlist_head), GFP_ATOMIC);
+	if (!tbl_mpp->known_gates) {
+		ret = -ENOMEM;
+		goto free_mpp;
+	}
+	INIT_HLIST_HEAD(tbl_mpp->known_gates);
 
 	/* Need no locking since this is during init */
 	RCU_INIT_POINTER(mesh_paths, tbl_path);
 	RCU_INIT_POINTER(mpp_paths, tbl_mpp);
 
 	return 0;
+
+free_mpp:
+	mesh_table_free(tbl_mpp, true);
+free_path:
+	mesh_table_free(tbl_path, true);
+	return ret;
 }
 
 void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
@@ -819,23 +1087,18 @@ void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
 	struct mesh_table *tbl;
 	struct mesh_path *mpath;
 	struct mpath_node *node;
-	struct hlist_node *p;
 	int i;
 
 	rcu_read_lock();
 	tbl = rcu_dereference(mesh_paths);
-	for_each_mesh_entry(tbl, p, node, i) {
+	for_each_mesh_entry(tbl, node, i) {
 		if (node->mpath->sdata != sdata)
 			continue;
 		mpath = node->mpath;
-		spin_lock_bh(&mpath->state_lock);
 		if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
 		    (!(mpath->flags & MESH_PATH_FIXED)) &&
-		     time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE)) {
-			spin_unlock_bh(&mpath->state_lock);
-			mesh_path_del(mpath->dst, mpath->sdata);
-		} else
-			spin_unlock_bh(&mpath->state_lock);
+		     time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
+			mesh_path_del(mpath->sdata, mpath->dst);
 	}
 	rcu_read_unlock();
 }
@@ -843,6 +1106,6 @@ void mesh_path_expire(struct ieee80211_sub_if_data *sdata)
 void mesh_pathtbl_unregister(void)
 {
 	/* no need for locking during exit path */
-	mesh_table_free(rcu_dereference_raw(mesh_paths), true);
-	mesh_table_free(rcu_dereference_raw(mpp_paths), true);
+	mesh_table_free(rcu_dereference_protected(mesh_paths, 1), true);
+	mesh_table_free(rcu_dereference_protected(mpp_paths, 1), true);
 }