diff options
Diffstat (limited to 'net/mac80211/mesh_pathtbl.c')
-rw-r--r-- | net/mac80211/mesh_pathtbl.c | 166 |
1 files changed, 109 insertions, 57 deletions
diff --git a/net/mac80211/mesh_pathtbl.c b/net/mac80211/mesh_pathtbl.c index 336ca9d..83ce48e 100644 --- a/net/mac80211/mesh_pathtbl.c +++ b/net/mac80211/mesh_pathtbl.c @@ -40,6 +40,50 @@ static struct mesh_table *mesh_paths; static struct mesh_table *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 struct mesh_table *mesh_table_alloc(int size_order) +{ + int i; + struct mesh_table *newtbl; + + newtbl = kmalloc(sizeof(struct mesh_table), GFP_KERNEL); + if (!newtbl) + return NULL; + + newtbl->hash_buckets = kzalloc(sizeof(struct hlist_head) * + (1 << size_order), GFP_KERNEL); + + if (!newtbl->hash_buckets) { + kfree(newtbl); + return NULL; + } + + newtbl->hashwlock = kmalloc(sizeof(spinlock_t) * + (1 << size_order), GFP_KERNEL); + 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 +91,7 @@ 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 +99,56 @@ 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; - - newtbl = mesh_table_alloc(tbl->size_order + 1); - if (!newtbl) - goto endgrow; + if (atomic_read(&oldtbl->entries) + < oldtbl->mean_chain_len * (oldtbl->hash_mask + 1)) + return -EAGAIN; - 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); /** * @@ -280,7 +320,7 @@ 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; @@ -295,7 +335,7 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata) hash_idx = mesh_table_hash(dst, sdata, mesh_paths); bucket = &mesh_paths->hash_buckets[hash_idx]; - spin_lock(&mesh_paths->hashwlock[hash_idx]); + spin_lock_bh(&mesh_paths->hashwlock[hash_idx]); err = -EEXIST; hlist_for_each_entry(node, n, bucket, list) { @@ -311,8 +351,8 @@ int mesh_path_add(u8 *dst, struct ieee80211_sub_if_data *sdata) mesh_paths_generation++; - spin_unlock(&mesh_paths->hashwlock[hash_idx]); - read_unlock(&pathtbl_resize_lock); + spin_unlock_bh(&mesh_paths->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 +360,8 @@ 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(&mesh_paths->hashwlock[hash_idx]); + read_unlock_bh(&pathtbl_resize_lock); kfree(new_node); err_node_alloc: kfree(new_mpath); @@ -334,15 +374,21 @@ void mesh_mpath_table_grow(void) { struct mesh_table *oldtbl, *newtbl; - write_lock(&pathtbl_resize_lock); + rcu_read_lock(); + newtbl = mesh_table_alloc(rcu_dereference(mesh_paths)->size_order + 1); + if (!newtbl) + return; + write_lock_bh(&pathtbl_resize_lock); oldtbl = mesh_paths; - newtbl = mesh_table_grow(mesh_paths); - if (!newtbl) { - write_unlock(&pathtbl_resize_lock); + if (mesh_table_grow(mesh_paths, newtbl) < 0) { + rcu_read_unlock(); + __mesh_table_free(newtbl); + write_unlock_bh(&pathtbl_resize_lock); return; } + rcu_read_unlock(); rcu_assign_pointer(mesh_paths, newtbl); - write_unlock(&pathtbl_resize_lock); + write_unlock_bh(&pathtbl_resize_lock); synchronize_rcu(); mesh_table_free(oldtbl, false); @@ -352,15 +398,21 @@ void mesh_mpp_table_grow(void) { struct mesh_table *oldtbl, *newtbl; - write_lock(&pathtbl_resize_lock); + rcu_read_lock(); + newtbl = mesh_table_alloc(rcu_dereference(mpp_paths)->size_order + 1); + if (!newtbl) + return; + write_lock_bh(&pathtbl_resize_lock); oldtbl = mpp_paths; - newtbl = mesh_table_grow(mpp_paths); - if (!newtbl) { - write_unlock(&pathtbl_resize_lock); + if (mesh_table_grow(mpp_paths, newtbl) < 0) { + rcu_read_unlock(); + __mesh_table_free(newtbl); + write_unlock_bh(&pathtbl_resize_lock); return; } + rcu_read_unlock(); rcu_assign_pointer(mpp_paths, newtbl); - write_unlock(&pathtbl_resize_lock); + write_unlock_bh(&pathtbl_resize_lock); synchronize_rcu(); mesh_table_free(oldtbl, false); @@ -394,7 +446,7 @@ 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; @@ -407,7 +459,7 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata) hash_idx = mesh_table_hash(dst, sdata, mpp_paths); bucket = &mpp_paths->hash_buckets[hash_idx]; - spin_lock(&mpp_paths->hashwlock[hash_idx]); + spin_lock_bh(&mpp_paths->hashwlock[hash_idx]); err = -EEXIST; hlist_for_each_entry(node, n, bucket, list) { @@ -421,8 +473,8 @@ int mpp_path_add(u8 *dst, u8 *mpp, struct ieee80211_sub_if_data *sdata) mpp_paths->mean_chain_len * (mpp_paths->hash_mask + 1)) grow = 1; - spin_unlock(&mpp_paths->hashwlock[hash_idx]); - read_unlock(&pathtbl_resize_lock); + spin_unlock_bh(&mpp_paths->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 +482,8 @@ 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(&mpp_paths->hashwlock[hash_idx]); + read_unlock_bh(&pathtbl_resize_lock); kfree(new_node); err_node_alloc: kfree(new_mpath); @@ -544,11 +596,11 @@ int mesh_path_del(u8 *addr, struct ieee80211_sub_if_data *sdata) int hash_idx; int err = 0; - read_lock(&pathtbl_resize_lock); + read_lock_bh(&pathtbl_resize_lock); hash_idx = mesh_table_hash(addr, sdata, mesh_paths); bucket = &mesh_paths->hash_buckets[hash_idx]; - spin_lock(&mesh_paths->hashwlock[hash_idx]); + spin_lock_bh(&mesh_paths->hashwlock[hash_idx]); hlist_for_each_entry(node, n, bucket, list) { mpath = node->mpath; if (mpath->sdata == sdata && @@ -566,8 +618,8 @@ 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(&mesh_paths->hashwlock[hash_idx]); + read_unlock_bh(&pathtbl_resize_lock); return err; } @@ -719,7 +771,7 @@ void mesh_path_expire(struct ieee80211_sub_if_data *sdata) struct hlist_node *p; int i; - read_lock(&pathtbl_resize_lock); + read_lock_bh(&pathtbl_resize_lock); for_each_mesh_entry(mesh_paths, p, node, i) { if (node->mpath->sdata != sdata) continue; @@ -734,7 +786,7 @@ void mesh_path_expire(struct ieee80211_sub_if_data *sdata) } else spin_unlock_bh(&mpath->state_lock); } - read_unlock(&pathtbl_resize_lock); + read_unlock_bh(&pathtbl_resize_lock); } void mesh_pathtbl_unregister(void) |