summaryrefslogtreecommitdiffstats
path: root/net/mac80211/mesh_pathtbl.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/mac80211/mesh_pathtbl.c')
-rw-r--r--net/mac80211/mesh_pathtbl.c308
1 files changed, 206 insertions, 102 deletions
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c
index 336ca9d0c5c..0d2faacc3e8 100644
--- a/net/mac80211/mesh_pathtbl.c
+++ b/net/mac80211/mesh_pathtbl.c
@@ -36,10 +36,77 @@ struct mpath_node {
struct mesh_path *mpath;
};
-static struct mesh_table *mesh_paths;
-static struct mesh_table *mpp_paths; /* Store paths for MPP&MAP */
+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. When reading the table (i.e. doing lookups) we are well protected
+ * by RCU
+ */
+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]);
+
+ return newtbl;
+}
+
static void __mesh_table_free(struct mesh_table *tbl)
{
kfree(tbl->hash_buckets);
@@ -47,7 +114,7 @@ static void __mesh_table_free(struct mesh_table *tbl)
kfree(tbl);
}
-void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
+static void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
{
struct hlist_head *mesh_hash;
struct hlist_node *p, *q;
@@ -55,60 +122,56 @@ void mesh_table_free(struct mesh_table *tbl, bool free_leafs)
mesh_hash = tbl->hash_buckets;
for (i = 0; i <= tbl->hash_mask; i++) {
- spin_lock(&tbl->hashwlock[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(&tbl->hashwlock[i]);
+ spin_unlock_bh(&tbl->hashwlock[i]);
}
__mesh_table_free(tbl);
}
-static struct mesh_table *mesh_table_grow(struct mesh_table *tbl)
+static int mesh_table_grow(struct mesh_table *oldtbl,
+ struct mesh_table *newtbl)
{
- struct mesh_table *newtbl;
struct hlist_head *oldhash;
struct hlist_node *p, *q;
int i;
- if (atomic_read(&tbl->entries)
- < tbl->mean_chain_len * (tbl->hash_mask + 1))
- goto endgrow;
+ if (atomic_read(&oldtbl->entries)
+ < oldtbl->mean_chain_len * (oldtbl->hash_mask + 1))
+ return -EAGAIN;
- newtbl = mesh_table_alloc(tbl->size_order + 1);
- if (!newtbl)
- goto endgrow;
-
- newtbl->free_node = tbl->free_node;
- newtbl->mean_chain_len = tbl->mean_chain_len;
- newtbl->copy_node = tbl->copy_node;
- atomic_set(&newtbl->entries, atomic_read(&tbl->entries));
+ newtbl->free_node = oldtbl->free_node;
+ newtbl->mean_chain_len = oldtbl->mean_chain_len;
+ newtbl->copy_node = oldtbl->copy_node;
+ atomic_set(&newtbl->entries, atomic_read(&oldtbl->entries));
- oldhash = tbl->hash_buckets;
- for (i = 0; i <= tbl->hash_mask; i++)
+ oldhash = oldtbl->hash_buckets;
+ for (i = 0; i <= oldtbl->hash_mask; i++)
hlist_for_each(p, &oldhash[i])
- if (tbl->copy_node(p, newtbl) < 0)
+ if (oldtbl->copy_node(p, newtbl) < 0)
goto errcopy;
- return newtbl;
+ return 0;
errcopy:
for (i = 0; i <= newtbl->hash_mask; i++) {
hlist_for_each_safe(p, q, &newtbl->hash_buckets[i])
- tbl->free_node(p, 0);
+ oldtbl->free_node(p, 0);
}
- __mesh_table_free(newtbl);
-endgrow:
- return NULL;
+ 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;
+}
-/* 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
- */
-static DEFINE_RWLOCK(pathtbl_resize_lock);
/**
*
@@ -218,12 +281,13 @@ struct mesh_path *mpp_path_lookup(u8 *dst, struct ieee80211_sub_if_data *sdata)
*/
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(mesh_paths, p, node, i) {
+ for_each_mesh_entry(tbl, p, node, i) {
if (sdata && node->mpath->sdata != sdata)
continue;
if (j++ == idx) {
@@ -253,6 +317,7 @@ 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;
@@ -280,7 +345,7 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
if (!new_node)
goto err_node_alloc;
- read_lock(&pathtbl_resize_lock);
+ read_lock_bh(&pathtbl_resize_lock);
memcpy(new_mpath->dst, dst, ETH_ALEN);
new_mpath->sdata = sdata;
new_mpath->flags = 0;
@@ -292,10 +357,12 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
spin_lock_init(&new_mpath->state_lock);
init_timer(&new_mpath->timer);
- hash_idx = mesh_table_hash(dst, sdata, mesh_paths);
- bucket = &mesh_paths->hash_buckets[hash_idx];
+ tbl = resize_dereference_mesh_paths();
+
+ hash_idx = mesh_table_hash(dst, sdata, tbl);
+ bucket = &tbl->hash_buckets[hash_idx];
- spin_lock(&mesh_paths->hashwlock[hash_idx]);
+ spin_lock_bh(&tbl->hashwlock[hash_idx]);
err = -EEXIST;
hlist_for_each_entry(node, n, bucket, list) {
@@ -305,14 +372,14 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
}
hlist_add_head_rcu(&new_node->list, bucket);
- if (atomic_inc_return(&mesh_paths->entries) >=
- mesh_paths->mean_chain_len * (mesh_paths->hash_mask + 1))
+ if (atomic_inc_return(&tbl->entries) >=
+ tbl->mean_chain_len * (tbl->hash_mask + 1))
grow = 1;
mesh_paths_generation++;
- spin_unlock(&mesh_paths->hashwlock[hash_idx]);
- read_unlock(&pathtbl_resize_lock);
+ 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);
@@ -320,8 +387,8 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata)
return 0;
err_exists:
- spin_unlock(&mesh_paths->hashwlock[hash_idx]);
- read_unlock(&pathtbl_resize_lock);
+ spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
kfree(new_node);
err_node_alloc:
kfree(new_mpath);
@@ -330,46 +397,59 @@ err_path_alloc:
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(&pathtbl_resize_lock);
- oldtbl = mesh_paths;
- newtbl = mesh_table_grow(mesh_paths);
- if (!newtbl) {
- write_unlock(&pathtbl_resize_lock);
- return;
+ 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);
- write_unlock(&pathtbl_resize_lock);
- synchronize_rcu();
- mesh_table_free(oldtbl, false);
+ 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(&pathtbl_resize_lock);
- oldtbl = mpp_paths;
- newtbl = mesh_table_grow(mpp_paths);
- if (!newtbl) {
- write_unlock(&pathtbl_resize_lock);
- return;
+ 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);
- write_unlock(&pathtbl_resize_lock);
+ call_rcu(&oldtbl->rcu_head, mesh_table_free_rcu);
- synchronize_rcu();
- mesh_table_free(oldtbl, false);
+ 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;
@@ -394,7 +474,7 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
if (!new_node)
goto err_node_alloc;
- read_lock(&pathtbl_resize_lock);
+ read_lock_bh(&pathtbl_resize_lock);
memcpy(new_mpath->dst, dst, ETH_ALEN);
memcpy(new_mpath->mpp, mpp, ETH_ALEN);
new_mpath->sdata = sdata;
@@ -404,10 +484,12 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
new_mpath->exp_time = jiffies;
spin_lock_init(&new_mpath->state_lock);
- hash_idx = mesh_table_hash(dst, sdata, mpp_paths);
- bucket = &mpp_paths->hash_buckets[hash_idx];
+ tbl = resize_dereference_mpp_paths();
+
+ hash_idx = mesh_table_hash(dst, sdata, tbl);
+ bucket = &tbl->hash_buckets[hash_idx];
- spin_lock(&mpp_paths->hashwlock[hash_idx]);
+ spin_lock_bh(&tbl->hashwlock[hash_idx]);
err = -EEXIST;
hlist_for_each_entry(node, n, bucket, list) {
@@ -417,12 +499,12 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
}
hlist_add_head_rcu(&new_node->list, bucket);
- if (atomic_inc_return(&mpp_paths->entries) >=
- mpp_paths->mean_chain_len * (mpp_paths->hash_mask + 1))
+ if (atomic_inc_return(&tbl->entries) >=
+ tbl->mean_chain_len * (tbl->hash_mask + 1))
grow = 1;
- spin_unlock(&mpp_paths->hashwlock[hash_idx]);
- read_unlock(&pathtbl_resize_lock);
+ spin_unlock_bh(&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);
@@ -430,8 +512,8 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata)
return 0;
err_exists:
- spin_unlock(&mpp_paths->hashwlock[hash_idx]);
- read_unlock(&pathtbl_resize_lock);
+ spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
kfree(new_node);
err_node_alloc:
kfree(new_mpath);
@@ -450,6 +532,7 @@ err_path_alloc:
*/
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;
@@ -458,10 +541,11 @@ void mesh_plink_broken(struct sta_info *sta)
int i;
rcu_read_lock();
- for_each_mesh_entry(mesh_paths, p, node, i) {
+ tbl = rcu_dereference(mesh_paths);
+ for_each_mesh_entry(tbl, p, node, i) {
mpath = node->mpath;
spin_lock_bh(&mpath->state_lock);
- if (mpath->next_hop == sta &&
+ if (rcu_dereference(mpath->next_hop) == sta &&
mpath->flags & MESH_PATH_ACTIVE &&
!(mpath->flags & MESH_PATH_FIXED)) {
mpath->flags &= ~MESH_PATH_ACTIVE;
@@ -490,30 +574,38 @@ void mesh_plink_broken(struct sta_info *sta)
*/
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;
- for_each_mesh_entry(mesh_paths, p, node, i) {
+ rcu_read_lock();
+ tbl = rcu_dereference(mesh_paths);
+ for_each_mesh_entry(tbl, p, node, i) {
mpath = node->mpath;
- if (mpath->next_hop == sta)
+ if (rcu_dereference(mpath->next_hop) == sta)
mesh_path_del(mpath->dst, mpath->sdata);
}
+ rcu_read_unlock();
}
void mesh_path_flush(struct ieee80211_sub_if_data *sdata)
{
+ struct mesh_table *tbl;
struct mesh_path *mpath;
struct mpath_node *node;
struct hlist_node *p;
int i;
- for_each_mesh_entry(mesh_paths, p, node, i) {
+ rcu_read_lock();
+ tbl = rcu_dereference(mesh_paths);
+ for_each_mesh_entry(tbl, p, node, i) {
mpath = node->mpath;
if (mpath->sdata == sdata)
mesh_path_del(mpath->dst, mpath->sdata);
}
+ rcu_read_unlock();
}
static void mesh_path_node_reclaim(struct rcu_head *rp)
@@ -537,6 +629,7 @@ static void mesh_path_node_reclaim(struct rcu_head *rp)
*/
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;
@@ -544,20 +637,21 @@ int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
int hash_idx;
int err = 0;
- read_lock(&pathtbl_resize_lock);
- hash_idx = mesh_table_hash(addr, sdata, mesh_paths);
- bucket = &mesh_paths->hash_buckets[hash_idx];
+ 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(&mesh_paths->hashwlock[hash_idx]);
+ spin_lock_bh(&tbl->hashwlock[hash_idx]);
hlist_for_each_entry(node, n, bucket, list) {
mpath = node->mpath;
if (mpath->sdata == sdata &&
- memcmp(addr, mpath->dst, ETH_ALEN) == 0) {
+ 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(&mesh_paths->entries);
+ atomic_dec(&tbl->entries);
spin_unlock_bh(&mpath->state_lock);
goto enddel;
}
@@ -566,8 +660,8 @@ int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata)
err = -ENXIO;
enddel:
mesh_paths_generation++;
- spin_unlock(&mesh_paths->hashwlock[hash_idx]);
- read_unlock(&pathtbl_resize_lock);
+ spin_unlock_bh(&tbl->hashwlock[hash_idx]);
+ read_unlock_bh(&pathtbl_resize_lock);
return err;
}
@@ -667,8 +761,10 @@ static void mesh_path_node_free(struct hlist_node *p, bool free_leafs)
struct mpath_node *node = hlist_entry(p, struct mpath_node, list);
mpath = node->mpath;
hlist_del_rcu(p);
- if (free_leafs)
+ if (free_leafs) {
+ del_timer_sync(&mpath->timer);
kfree(mpath);
+ }
kfree(node);
}
@@ -693,52 +789,60 @@ static int mesh_path_node_copy(struct hlist_node *p, struct mesh_table *newtbl)
int mesh_pathtbl_init(void)
{
- mesh_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
- if (!mesh_paths)
+ struct mesh_table *tbl_path, *tbl_mpp;
+
+ tbl_path = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
+ if (!tbl_path)
return -ENOMEM;
- mesh_paths->free_node = &mesh_path_node_free;
- mesh_paths->copy_node = &mesh_path_node_copy;
- mesh_paths->mean_chain_len = MEAN_CHAIN_LEN;
+ tbl_path->free_node = &mesh_path_node_free;
+ tbl_path->copy_node = &mesh_path_node_copy;
+ tbl_path->mean_chain_len = MEAN_CHAIN_LEN;
- mpp_paths = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
- if (!mpp_paths) {
- mesh_table_free(mesh_paths, true);
+ tbl_mpp = mesh_table_alloc(INIT_PATHS_SIZE_ORDER);
+ if (!tbl_mpp) {
+ mesh_table_free(tbl_path, true);
return -ENOMEM;
}
- mpp_paths->free_node = &mesh_path_node_free;
- mpp_paths->copy_node = &mesh_path_node_copy;
- mpp_paths->mean_chain_len = MEAN_CHAIN_LEN;
+ tbl_mpp->free_node = &mesh_path_node_free;
+ tbl_mpp->copy_node = &mesh_path_node_copy;
+ tbl_mpp->mean_chain_len = MEAN_CHAIN_LEN;
+
+ /* Need no locking since this is during init */
+ RCU_INIT_POINTER(mesh_paths, tbl_path);
+ RCU_INIT_POINTER(mpp_paths, tbl_mpp);
return 0;
}
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;
- read_lock(&pathtbl_resize_lock);
- for_each_mesh_entry(mesh_paths, p, node, 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;
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)) {
+ 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);
}
- read_unlock(&pathtbl_resize_lock);
+ rcu_read_unlock();
}
void mesh_pathtbl_unregister(void)
{
- mesh_table_free(mesh_paths, true);
- mesh_table_free(mpp_paths, true);
+ /* 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);
}
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-24 10:08:19 +0000