zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/net/mac80211/mesh_pathtbl.c b/ap/os/linux/linux-3.4.x/net/mac80211/mesh_pathtbl.c
new file mode 100644
index 0000000..49aaefd
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/mac80211/mesh_pathtbl.c
@@ -0,0 +1,1124 @@
+/*
+ * Copyright (c) 2008, 2009 open80211s Ltd.
+ * Author: Luis Carlos Cobo <luisca@cozybit.com>
+ *
+ * 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 <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/random.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <net/mac80211.h>
+#include "wme.h"
+#include "ieee80211_i.h"
+#include "mesh.h"
+
+#ifdef CONFIG_MAC80211_VERBOSE_MPATH_DEBUG
+#define mpath_dbg(fmt, args...) printk(KERN_DEBUG fmt, ##args)
+#else
+#define mpath_dbg(fmt, args...) do { (void)(0); } while (0)
+#endif
+
+/* There will be initially 2^INIT_PATHS_SIZE_ORDER buckets */
+#define INIT_PATHS_SIZE_ORDER 2
+
+/* 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))
+
+struct mpath_node {
+ struct hlist_node list;
+ struct rcu_head rcu;
+ /* This indirection allows two different tables to point to the same
+ * mesh_path structure, useful when resizing
+ */
+ struct mesh_path *mpath;
+};
+
+static struct mesh_table __rcu *mesh_paths;
+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. 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);
+
+
+static inline struct mesh_table *resize_dereference_mesh_paths(void)
+{
+ return rcu_dereference_protected(mesh_paths,
+ lockdep_is_held(&pathtbl_resize_lock));
+}
+
+static inline struct mesh_table *resize_dereference_mpp_paths(void)
+{
+ return rcu_dereference_protected(mpp_paths,
+ lockdep_is_held(&pathtbl_resize_lock));
+}
+
+/*
+ * CAREFUL -- "tbl" must not be an expression,
+ * in particular not an rcu_dereference(), since
+ * 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) \
+ for (i = 0; i <= tbl->hash_mask; i++) \
+ hlist_for_each_entry_rcu(node, p, &tbl->hash_buckets[i], list)
+
+
+static struct mesh_table *mesh_table_alloc(int size_order)
+{
+ int i;
+ struct mesh_table *newtbl;
+
+ newtbl = kmalloc(sizeof(struct mesh_table), GFP_ATOMIC);
+ if (!newtbl)
+ return NULL;
+
+ newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) *
+ (1 << size_order), GFP_ATOMIC);
+
+ if (!newtbl->hash_buckets) {
+ kfree(newtbl);
+ return NULL;
+ }
+
+ newtbl->hashwlock = kmalloc(sizeof(spinlock_t) *
+ (1 << size_order), GFP_ATOMIC);
+ if (!newtbl->hashwlock) {
+ kfree(newtbl->hash_buckets);
+ kfree(newtbl);
+ return NULL;
+ }
+
+ newtbl->size_order = size_order;
+ newtbl->hash_mask = (1 << size_order) - 1;
+ atomic_set(&newtbl->entries, 0);
+ get_random_bytes(&newtbl->hash_rnd,
+ 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;
+}
+
+static void __mesh_table_free(struct mesh_table *tbl)
+{
+ kfree(tbl->hash_buckets);
+ kfree(tbl->hashwlock);
+ kfree(tbl);
+}
+
+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;
+ for (i = 0; i <= tbl->hash_mask; i++) {
+ spin_lock_bh(&tbl->hashwlock[i]);
+ hlist_for_each_safe(p, q, &mesh_hash[i]) {
+ tbl->free_node(p, free_leafs);
+ atomic_dec(&tbl->entries);
+ }
+ spin_unlock_bh(&tbl->hashwlock[i]);
+ }
+ if (free_leafs) {
+ spin_lock_bh(&tbl->gates_lock);
+ hlist_for_each_entry_safe(gate, p, 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);
+}
+
+static int mesh_table_grow(struct mesh_table *oldtbl,
+ struct mesh_table *newtbl)
+{
+ struct hlist_head *oldhash;
+ struct hlist_node *p, *q;
+ int i;
+
+ if (atomic_read(&oldtbl->entries)
+ < oldtbl->mean_chain_len * (oldtbl->hash_mask + 1))
+ return -EAGAIN;
+
+ 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;
+ for (i = 0; i <= oldtbl->hash_mask; i++)
+ hlist_for_each(p, &oldhash[i])
+ if (oldtbl->copy_node(p, newtbl) < 0)
+ goto errcopy;
+
+ return 0;
+
+errcopy:
+ for (i = 0; i <= newtbl->hash_mask; i++) {
+ hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
+ oldtbl->free_node(p, 0);
+ }
+ return -ENOMEM;
+}
+
+static u32 mesh_table_hash(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;
+}
+
+
+/**
+ *
+ * mesh_path_assign_nexthop - update mesh path next hop
+ *
+ * @mpath: mesh path to update
+ * @sta: next hop to assign
+ *
+ * Locking: mpath->state_lock must be held when calling this function
+ */
+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) {
+ hdr = (struct ieee80211_hdr *) skb->data;
+ memcpy(hdr->addr1, sta->sta.addr, ETH_ALEN);
+ memcpy(hdr->addr2, mpath->sdata->vif.addr, ETH_ALEN);
+ __skb_queue_tail(&tmpq, skb);
+ }
+
+ 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_move_to_queue - Move or copy frames from one mpath queue to another
+ *
+ * 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.
+ */
+static void mesh_path_move_to_queue(struct mesh_path *gate_mpath,
+ struct mesh_path *from_mpath,
+ bool copy)
+{
+ struct sk_buff *skb, *cp_skb = NULL;
+ struct sk_buff_head gateq, failq;
+ unsigned long flags;
+ int num_skbs;
+
+ BUG_ON(gate_mpath == from_mpath);
+ BUG_ON(!gate_mpath->next_hop);
+
+ __skb_queue_head_init(&gateq);
+ __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);
+
+ num_skbs = skb_queue_len(&failq);
+
+ while (num_skbs--) {
+ skb = __skb_dequeue(&failq);
+ if (copy) {
+ cp_skb = skb_copy(skb, GFP_ATOMIC);
+ if (cp_skb)
+ __skb_queue_tail(&failq, cp_skb);
+ }
+
+ prepare_for_gate(skb, gate_mpath->dst, gate_mpath);
+ __skb_queue_tail(&gateq, skb);
+ }
+
+ spin_lock_irqsave(&gate_mpath->frame_queue.lock, flags);
+ skb_queue_splice(&gateq, &gate_mpath->frame_queue);
+ mpath_dbg("Mpath queue for gate %pM has %d frames\n",
+ gate_mpath->dst,
+ skb_queue_len(&gate_mpath->frame_queue));
+ spin_unlock_irqrestore(&gate_mpath->frame_queue.lock, flags);
+
+ 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);
+}
+
+
+static struct mesh_path *mpath_lookup(struct mesh_table *tbl, u8 *dst,
+ struct ieee80211_sub_if_data *sdata)
+{
+ struct mesh_path *mpath;
+ struct hlist_node *n;
+ struct hlist_head *bucket;
+ struct mpath_node *node;
+
+ 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 &&
+ compare_ether_addr(dst, mpath->dst) == 0) {
+ if (MPATH_EXPIRED(mpath)) {
+ spin_lock_bh(&mpath->state_lock);
+ mpath->flags &= ~MESH_PATH_ACTIVE;
+ spin_unlock_bh(&mpath->state_lock);
+ }
+ return mpath;
+ }
+ }
+ return NULL;
+}
+
+/**
+ * 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
+ *
+ * Locking: must be called within a read rcu section.
+ */
+struct mesh_path *mesh_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+{
+ return mpath_lookup(rcu_dereference(mesh_paths), dst, sdata);
+}
+
+struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
+{
+ 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
+ * @idx: index
+ * @sdata: local subif, or NULL for all entries
+ *
+ * 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_by_idx(int idx, struct ieee80211_sub_if_data *sdata)
+{
+ 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) {
+ if (sdata && node->mpath->sdata != sdata)
+ continue;
+ if (j++ == idx) {
+ if (MPATH_EXPIRED(node->mpath)) {
+ spin_lock_bh(&node->mpath->state_lock);
+ node->mpath->flags &= ~MESH_PATH_ACTIVE;
+ spin_unlock_bh(&node->mpath->state_lock);
+ }
+ return node->mpath;
+ }
+ }
+
+ return NULL;
+}
+
+/**
+ * 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;
+ struct hlist_node *n;
+ int err;
+
+ rcu_read_lock();
+ tbl = rcu_dereference(mesh_paths);
+
+ hlist_for_each_entry_rcu(gate, n, 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);
+ rcu_read_unlock();
+ mpath_dbg("Mesh path (%s): Recorded new gate: %pM. %d known gates\n",
+ mpath->sdata->name, mpath->dst,
+ mpath->sdata->u.mesh.num_gates);
+ return 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
+ *
+ * Returns: 0 on success
+ *
+ * Locking: must be called inside rcu_read_lock() section
+ */
+static int mesh_gate_del(struct mesh_table *tbl, struct mesh_path *mpath)
+{
+ struct mpath_node *gate;
+ struct hlist_node *p, *q;
+
+ hlist_for_each_entry_safe(gate, p, q, tbl->known_gates, list)
+ if (gate->mpath == mpath) {
+ 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("Mesh path (%s): Deleted gate: %pM. "
+ "%d known gates\n", mpath->sdata->name,
+ mpath->dst, mpath->sdata->u.mesh.num_gates);
+ break;
+ }
+
+ return 0;
+}
+
+/**
+ * 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)
+ * @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 ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct ieee80211_local *local = sdata->local;
+ struct mesh_table *tbl;
+ 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 (compare_ether_addr(dst, sdata->vif.addr) == 0)
+ /* never add ourselves as neighbours */
+ return -ENOTSUPP;
+
+ if (is_multicast_ether_addr(dst))
+ return -ENOTSUPP;
+
+ if (atomic_add_unless(&sdata->u.mesh.mpaths, 1, MESH_MAX_MPATHS) == 0)
+ return -ENOSPC;
+
+ err = -ENOMEM;
+ new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
+ if (!new_mpath)
+ goto err_path_alloc;
+
+ new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
+ if (!new_node)
+ goto err_node_alloc;
+
+ read_lock_bh(&pathtbl_resize_lock);
+ memcpy(new_mpath->dst, dst, ETH_ALEN);
+ new_mpath->sdata = sdata;
+ new_mpath->flags = 0;
+ skb_queue_head_init(&new_mpath->frame_queue);
+ new_node->mpath = new_mpath;
+ new_mpath->timer.data = (unsigned long) new_mpath;
+ new_mpath->timer.function = mesh_path_timer;
+ new_mpath->exp_time = jiffies;
+ 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(&tbl->hashwlock[hash_idx]);
+
+ err = -EEXIST;
+ hlist_for_each_entry(node, n, bucket, list) {
+ mpath = node->mpath;
+ if (mpath->sdata == sdata &&
+ compare_ether_addr(dst, mpath->dst) == 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))
+ grow = 1;
+
+ mesh_paths_generation++;
+
+ spin_unlock(&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(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
+ kfree(new_node);
+err_node_alloc:
+ kfree(new_mpath);
+err_path_alloc:
+ atomic_dec(&sdata->u.mesh.mpaths);
+ return err;
+}
+
+static void mesh_table_free_rcu(struct rcu_head *rcu)
+{
+ struct mesh_table *tbl = container_of(rcu, struct mesh_table, rcu_head);
+
+ mesh_table_free(tbl, false);
+}
+
+void mesh_mpath_table_grow(void)
+{
+ struct mesh_table *oldtbl, *newtbl;
+
+ write_lock_bh(&pathtbl_resize_lock);
+ oldtbl = resize_dereference_mesh_paths();
+ newtbl = mesh_table_alloc(oldtbl->size_order + 1);
+ if (!newtbl)
+ goto out;
+ if (mesh_table_grow(oldtbl, newtbl) < 0) {
+ __mesh_table_free(newtbl);
+ goto out;
+ }
+ rcu_assign_pointer(mesh_paths, newtbl);
+
+ call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
+
+ out:
+ write_unlock_bh(&pathtbl_resize_lock);
+}
+
+void mesh_mpp_table_grow(void)
+{
+ struct mesh_table *oldtbl, *newtbl;
+
+ write_lock_bh(&pathtbl_resize_lock);
+ oldtbl = resize_dereference_mpp_paths();
+ newtbl = mesh_table_alloc(oldtbl->size_order + 1);
+ if (!newtbl)
+ goto out;
+ if (mesh_table_grow(oldtbl, newtbl) < 0) {
+ __mesh_table_free(newtbl);
+ goto out;
+ }
+ rcu_assign_pointer(mpp_paths, newtbl);
+ call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
+
+ out:
+ write_unlock_bh(&pathtbl_resize_lock);
+}
+
+int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
+{
+ struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+ struct ieee80211_local *local = sdata->local;
+ struct mesh_table *tbl;
+ 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 (compare_ether_addr(dst, sdata->vif.addr) == 0)
+ /* never add ourselves as neighbours */
+ return -ENOTSUPP;
+
+ if (is_multicast_ether_addr(dst))
+ return -ENOTSUPP;
+
+ err = -ENOMEM;
+ new_mpath = kzalloc(sizeof(struct mesh_path), GFP_ATOMIC);
+ if (!new_mpath)
+ goto err_path_alloc;
+
+ new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
+ if (!new_node)
+ goto err_node_alloc;
+
+ read_lock_bh(&pathtbl_resize_lock);
+ memcpy(new_mpath->dst, dst, ETH_ALEN);
+ memcpy(new_mpath->mpp, mpp, ETH_ALEN);
+ new_mpath->sdata = 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);
+
+ tbl = resize_dereference_mpp_paths();
+
+ hash_idx = mesh_table_hash(dst, sdata, tbl);
+ bucket = &tbl->hash_buckets[hash_idx];
+
+ spin_lock(&tbl->hashwlock[hash_idx]);
+
+ err = -EEXIST;
+ hlist_for_each_entry(node, n, bucket, list) {
+ mpath = node->mpath;
+ if (mpath->sdata == sdata &&
+ compare_ether_addr(dst, mpath->dst) == 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))
+ grow = 1;
+
+ spin_unlock(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
+ if (grow) {
+ set_bit(MESH_WORK_GROW_MPP_TABLE, &ifmsh->wrkq_flags);
+ ieee80211_queue_work(&local->hw, &sdata->work);
+ }
+ return 0;
+
+err_exists:
+ spin_unlock(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
+ kfree(new_node);
+err_node_alloc:
+ kfree(new_mpath);
+err_path_alloc:
+ return err;
+}
+
+
+/**
+ * mesh_plink_broken - deactivates paths and sends perr when a link breaks
+ *
+ * @sta: broken peer link
+ *
+ * This function must be called from the rate control algorithm if enough
+ * delivery errors suggest that a peer link is no longer usable.
+ */
+void mesh_plink_broken(struct sta_info *sta)
+{
+ struct mesh_table *tbl;
+ 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;
+ __le16 reason = cpu_to_le16(WLAN_REASON_MESH_PATH_DEST_UNREACHABLE);
+
+ rcu_read_lock();
+ tbl = rcu_dereference(mesh_paths);
+ for_each_mesh_entry(tbl, p, node, i) {
+ mpath = node->mpath;
+ 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),
+ reason, bcast, sdata);
+ }
+ }
+ 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
+ *
+ * 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
+ * allows path creation. This will happen before the sta can be freed (because
+ * sta_info_destroy() calls this) so any reader in a rcu read block will be
+ * protected against the plink disappearing.
+ */
+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();
+ read_lock_bh(&pathtbl_resize_lock);
+ tbl = resize_dereference_mesh_paths();
+ for_each_mesh_entry(tbl, p, node, i) {
+ mpath = node->mpath;
+ 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();
+}
+
+static void table_flush_by_iface(struct mesh_table *tbl,
+ struct ieee80211_sub_if_data *sdata)
+{
+ struct mesh_path *mpath;
+ struct mpath_node *node;
+ struct hlist_node *p;
+ int i;
+
+ WARN_ON(!rcu_read_lock_held());
+ for_each_mesh_entry(tbl, p, node, i) {
+ mpath = node->mpath;
+ if (mpath->sdata != sdata)
+ continue;
+ spin_lock_bh(&tbl->hashwlock[i]);
+ __mesh_path_del(tbl, node);
+ spin_unlock_bh(&tbl->hashwlock[i]);
+ }
+}
+
+/**
+ * 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 mesh_table *tbl;
+
+ 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();
+}
+
+/**
+ * mesh_path_del - delete a mesh path from the table
+ *
+ * @addr: dst address (ETH_ALEN length)
+ * @sdata: local subif
+ *
+ * Returns: 0 if successful
+ */
+int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
+{
+ 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;
+
+ read_lock_bh(&pathtbl_resize_lock);
+ tbl = resize_dereference_mesh_paths();
+ hash_idx = mesh_table_hash(addr, sdata, tbl);
+ bucket = &tbl->hash_buckets[hash_idx];
+
+ spin_lock(&tbl->hashwlock[hash_idx]);
+ hlist_for_each_entry(node, n, bucket, list) {
+ mpath = node->mpath;
+ if (mpath->sdata == sdata &&
+ compare_ether_addr(addr, mpath->dst) == 0) {
+ __mesh_path_del(tbl, node);
+ goto enddel;
+ }
+ }
+
+ err = -ENXIO;
+enddel:
+ mesh_paths_generation++;
+ spin_unlock(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
+ return err;
+}
+
+/**
+ * mesh_path_tx_pending - sends pending frames in a mesh path queue
+ *
+ * @mpath: mesh path to activate
+ *
+ * Locking: the state_lock of the mpath structure must NOT be held when calling
+ * this function.
+ */
+void mesh_path_tx_pending(struct mesh_path *mpath)
+{
+ if (mpath->flags & MESH_PATH_ACTIVE)
+ ieee80211_add_pending_skbs(mpath->sdata->local,
+ &mpath->frame_queue);
+}
+
+/**
+ * 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 hlist_node *n;
+ 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, n, known_gates, list) {
+ if (gate->mpath->sdata != sdata)
+ continue;
+
+ if (gate->mpath->flags & MESH_PATH_ACTIVE) {
+ mpath_dbg("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("Not forwarding %p\n", gate->mpath);
+ mpath_dbg("flags %x\n", gate->mpath->flags);
+ }
+ }
+
+ hlist_for_each_entry_rcu(gate, n, known_gates, list)
+ if (gate->mpath->sdata == sdata) {
+ mpath_dbg("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
+ *
+ * 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)
+{
+ kfree_skb(skb);
+ sdata->u.mesh.mshstats.dropped_frames_no_route++;
+}
+
+/**
+ * mesh_path_flush_pending - free the pending queue of a mesh path
+ *
+ * @mpath: mesh path whose queue has to be freed
+ *
+ * Locking: the function must me called within a rcu_read_lock region
+ */
+void mesh_path_flush_pending(struct mesh_path *mpath)
+{
+ struct sk_buff *skb;
+
+ while ((skb = skb_dequeue(&mpath->frame_queue)) != NULL)
+ mesh_path_discard_frame(skb, mpath->sdata);
+}
+
+/**
+ * mesh_path_fix_nexthop - force a specific next hop for a mesh path
+ *
+ * @mpath: the mesh path to modify
+ * @next_hop: the next hop to force
+ *
+ * Locking: this function must be called holding mpath->state_lock
+ */
+void mesh_path_fix_nexthop(struct mesh_path *mpath, struct sta_info *next_hop)
+{
+ spin_lock_bh(&mpath->state_lock);
+ mesh_path_assign_nexthop(mpath, next_hop);
+ mpath->sn = 0xffff;
+ mpath->metric = 0;
+ mpath->hop_count = 0;
+ mpath->exp_time = 0;
+ mpath->flags |= MESH_PATH_FIXED;
+ mesh_path_activate(mpath);
+ spin_unlock_bh(&mpath->state_lock);
+ mesh_path_tx_pending(mpath);
+}
+
+static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
+{
+ struct mesh_path *mpath;
+ struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
+ mpath = node->mpath;
+ hlist_del_rcu(p);
+ if (free_leafs) {
+ del_timer_sync(&mpath->timer);
+ kfree(mpath);
+ }
+ kfree(node);
+}
+
+static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
+{
+ struct mesh_path *mpath;
+ struct mpath_node *node, *new_node;
+ u32 hash_idx;
+
+ new_node = kmalloc(sizeof(struct mpath_node), GFP_ATOMIC);
+ if (new_node == NULL)
+ return -ENOMEM;
+
+ node = hlist_entry(p, struct mpath_node, list);
+ mpath = node->mpath;
+ new_node->mpath = mpath;
+ hash_idx = mesh_table_hash(mpath->dst, mpath->sdata, newtbl);
+ hlist_add_head(&new_node->list,
+ &newtbl->hash_buckets[hash_idx]);
+ return 0;
+}
+
+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)
+ return -ENOMEM;
+ 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) {
+ 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)
+{
+ 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) {
+ if (node->mpath->sdata != sdata)
+ continue;
+ mpath = node->mpath;
+ if ((!(mpath->flags & MESH_PATH_RESOLVING)) &&
+ (!(mpath->flags & MESH_PATH_FIXED)) &&
+ time_after(jiffies, mpath->exp_time + MESH_PATH_EXPIRE))
+ mesh_path_del(mpath->dst, mpath->sdata);
+ }
+ rcu_read_unlock();
+}
+
+void mesh_pathtbl_unregister(void)
+{
+ /* no need for locking during exit path */
+ mesh_table_free(rcu_dereference_protected(mesh_paths, 1), true);
+ mesh_table_free(rcu_dereference_protected(mpp_paths, 1), true);
+}