diff --git a/MAINTAINERS b/MAINTAINERS index e902b635cbfc8c22649b1cca87d4e956ee26b738..99f95279e45b3233bba4af5fcfe5af5e35d6d039 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -9936,6 +9936,7 @@ F: net/rfkill/ RHASHTABLE M: Thomas Graf +M: Herbert Xu L: netdev@vger.kernel.org S: Maintained F: lib/rhashtable.c diff --git a/include/linux/rhashtable.h b/include/linux/rhashtable.h index 3eef0802a0cdb24251fac396eaaa9bbef6e24884..8b72ee710f956205f980c755a587fe9a0a25b6a0 100644 --- a/include/linux/rhashtable.h +++ b/include/linux/rhashtable.h @@ -173,7 +173,7 @@ struct rhashtable_walker { struct rhashtable_iter { struct rhashtable *ht; struct rhash_head *p; - struct rhashtable_walker *walker; + struct rhashtable_walker walker; unsigned int slot; unsigned int skip; }; @@ -346,8 +346,8 @@ struct bucket_table *rhashtable_insert_slow(struct rhashtable *ht, struct bucket_table *old_tbl); int rhashtable_insert_rehash(struct rhashtable *ht, struct bucket_table *tbl); -int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter, - gfp_t gfp); +void rhashtable_walk_enter(struct rhashtable *ht, + struct rhashtable_iter *iter); void rhashtable_walk_exit(struct rhashtable_iter *iter); int rhashtable_walk_start(struct rhashtable_iter *iter) __acquires(RCU); void *rhashtable_walk_next(struct rhashtable_iter *iter); @@ -906,4 +906,12 @@ static inline int rhashtable_replace_fast( return err; } +/* Obsolete function, do not use in new code. */ +static inline int rhashtable_walk_init(struct rhashtable *ht, + struct rhashtable_iter *iter, gfp_t gfp) +{ + rhashtable_walk_enter(ht, iter); + return 0; +} + #endif /* _LINUX_RHASHTABLE_H */ diff --git a/lib/rhashtable.c b/lib/rhashtable.c index 5ba520b544d73ff1a62705584d1971aeee6ec2ba..97e3cf08142c146280818966e220065aa6f720a1 100644 --- a/lib/rhashtable.c +++ b/lib/rhashtable.c @@ -489,10 +489,9 @@ struct bucket_table *rhashtable_insert_slow(struct rhashtable *ht, EXPORT_SYMBOL_GPL(rhashtable_insert_slow); /** - * rhashtable_walk_init - Initialise an iterator + * rhashtable_walk_enter - Initialise an iterator * @ht: Table to walk over * @iter: Hash table Iterator - * @gfp: GFP flags for allocations * * This function prepares a hash table walk. * @@ -507,30 +506,22 @@ EXPORT_SYMBOL_GPL(rhashtable_insert_slow); * This function may sleep so you must not call it from interrupt * context or with spin locks held. * - * You must call rhashtable_walk_exit if this function returns - * successfully. + * You must call rhashtable_walk_exit after this function returns. */ -int rhashtable_walk_init(struct rhashtable *ht, struct rhashtable_iter *iter, - gfp_t gfp) +void rhashtable_walk_enter(struct rhashtable *ht, struct rhashtable_iter *iter) { iter->ht = ht; iter->p = NULL; iter->slot = 0; iter->skip = 0; - iter->walker = kmalloc(sizeof(*iter->walker), gfp); - if (!iter->walker) - return -ENOMEM; - spin_lock(&ht->lock); - iter->walker->tbl = + iter->walker.tbl = rcu_dereference_protected(ht->tbl, lockdep_is_held(&ht->lock)); - list_add(&iter->walker->list, &iter->walker->tbl->walkers); + list_add(&iter->walker.list, &iter->walker.tbl->walkers); spin_unlock(&ht->lock); - - return 0; } -EXPORT_SYMBOL_GPL(rhashtable_walk_init); +EXPORT_SYMBOL_GPL(rhashtable_walk_enter); /** * rhashtable_walk_exit - Free an iterator @@ -541,10 +532,9 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_init); void rhashtable_walk_exit(struct rhashtable_iter *iter) { spin_lock(&iter->ht->lock); - if (iter->walker->tbl) - list_del(&iter->walker->list); + if (iter->walker.tbl) + list_del(&iter->walker.list); spin_unlock(&iter->ht->lock); - kfree(iter->walker); } EXPORT_SYMBOL_GPL(rhashtable_walk_exit); @@ -570,12 +560,12 @@ int rhashtable_walk_start(struct rhashtable_iter *iter) rcu_read_lock(); spin_lock(&ht->lock); - if (iter->walker->tbl) - list_del(&iter->walker->list); + if (iter->walker.tbl) + list_del(&iter->walker.list); spin_unlock(&ht->lock); - if (!iter->walker->tbl) { - iter->walker->tbl = rht_dereference_rcu(ht->tbl, ht); + if (!iter->walker.tbl) { + iter->walker.tbl = rht_dereference_rcu(ht->tbl, ht); return -EAGAIN; } @@ -597,7 +587,7 @@ EXPORT_SYMBOL_GPL(rhashtable_walk_start); */ void *rhashtable_walk_next(struct rhashtable_iter *iter) { - struct bucket_table *tbl = iter->walker->tbl; + struct bucket_table *tbl = iter->walker.tbl; struct rhashtable *ht = iter->ht; struct rhash_head *p = iter->p; @@ -630,8 +620,8 @@ void *rhashtable_walk_next(struct rhashtable_iter *iter) /* Ensure we see any new tables. */ smp_rmb(); - iter->walker->tbl = rht_dereference_rcu(tbl->future_tbl, ht); - if (iter->walker->tbl) { + iter->walker.tbl = rht_dereference_rcu(tbl->future_tbl, ht); + if (iter->walker.tbl) { iter->slot = 0; iter->skip = 0; return ERR_PTR(-EAGAIN); @@ -651,7 +641,7 @@ void rhashtable_walk_stop(struct rhashtable_iter *iter) __releases(RCU) { struct rhashtable *ht; - struct bucket_table *tbl = iter->walker->tbl; + struct bucket_table *tbl = iter->walker.tbl; if (!tbl) goto out; @@ -660,9 +650,9 @@ void rhashtable_walk_stop(struct rhashtable_iter *iter) spin_lock(&ht->lock); if (tbl->rehash < tbl->size) - list_add(&iter->walker->list, &tbl->walkers); + list_add(&iter->walker.list, &tbl->walkers); else - iter->walker->tbl = NULL; + iter->walker.tbl = NULL; spin_unlock(&ht->lock); iter->p = NULL; diff --git a/net/netlink/diag.c b/net/netlink/diag.c index 8dd836a8dd60ce67c3b2b910f18f80f28cc05b7c..3e3e2534478ace7ff041a6f8787fd7fe9c7fddda 100644 --- a/net/netlink/diag.c +++ b/net/netlink/diag.c @@ -63,43 +63,75 @@ static int sk_diag_fill(struct sock *sk, struct sk_buff *skb, static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, int protocol, int s_num) { + struct rhashtable_iter *hti = (void *)cb->args[2]; struct netlink_table *tbl = &nl_table[protocol]; - struct rhashtable *ht = &tbl->hash; - const struct bucket_table *htbl = rht_dereference_rcu(ht->tbl, ht); struct net *net = sock_net(skb->sk); struct netlink_diag_req *req; struct netlink_sock *nlsk; struct sock *sk; - int ret = 0, num = 0, i; + int num = 2; + int ret = 0; req = nlmsg_data(cb->nlh); - for (i = 0; i < htbl->size; i++) { - struct rhash_head *pos; + if (s_num > 1) + goto mc_list; - rht_for_each_entry_rcu(nlsk, pos, htbl, i, node) { - sk = (struct sock *)nlsk; + num--; - if (!net_eq(sock_net(sk), net)) - continue; - if (num < s_num) { - num++; + if (!hti) { + hti = kmalloc(sizeof(*hti), GFP_KERNEL); + if (!hti) + return -ENOMEM; + + cb->args[2] = (long)hti; + } + + if (!s_num) + rhashtable_walk_enter(&tbl->hash, hti); + + ret = rhashtable_walk_start(hti); + if (ret == -EAGAIN) + ret = 0; + if (ret) + goto stop; + + while ((nlsk = rhashtable_walk_next(hti))) { + if (IS_ERR(nlsk)) { + ret = PTR_ERR(nlsk); + if (ret == -EAGAIN) { + ret = 0; continue; } + break; + } - if (sk_diag_fill(sk, skb, req, - NETLINK_CB(cb->skb).portid, - cb->nlh->nlmsg_seq, - NLM_F_MULTI, - sock_i_ino(sk)) < 0) { - ret = 1; - goto done; - } + sk = (struct sock *)nlsk; - num++; + if (!net_eq(sock_net(sk), net)) + continue; + + if (sk_diag_fill(sk, skb, req, + NETLINK_CB(cb->skb).portid, + cb->nlh->nlmsg_seq, + NLM_F_MULTI, + sock_i_ino(sk)) < 0) { + ret = 1; + break; } } +stop: + rhashtable_walk_stop(hti); + if (ret) + goto done; + + rhashtable_walk_exit(hti); + cb->args[2] = 0; + num++; + +mc_list: + read_lock(&nl_table_lock); sk_for_each_bound(sk, &tbl->mc_list) { if (sk_hashed(sk)) continue; @@ -116,13 +148,14 @@ static int __netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb, NLM_F_MULTI, sock_i_ino(sk)) < 0) { ret = 1; - goto done; + break; } num++; } + read_unlock(&nl_table_lock); + done: cb->args[0] = num; - cb->args[1] = protocol; return ret; } @@ -131,20 +164,20 @@ static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) { struct netlink_diag_req *req; int s_num = cb->args[0]; + int err = 0; req = nlmsg_data(cb->nlh); - rcu_read_lock(); - read_lock(&nl_table_lock); - if (req->sdiag_protocol == NDIAG_PROTO_ALL) { int i; for (i = cb->args[1]; i < MAX_LINKS; i++) { - if (__netlink_diag_dump(skb, cb, i, s_num)) + err = __netlink_diag_dump(skb, cb, i, s_num); + if (err) break; s_num = 0; } + cb->args[1] = i; } else { if (req->sdiag_protocol >= MAX_LINKS) { read_unlock(&nl_table_lock); @@ -152,13 +185,22 @@ static int netlink_diag_dump(struct sk_buff *skb, struct netlink_callback *cb) return -ENOENT; } - __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num); + err = __netlink_diag_dump(skb, cb, req->sdiag_protocol, s_num); } - read_unlock(&nl_table_lock); - rcu_read_unlock(); + return err < 0 ? err : skb->len; +} + +static int netlink_diag_dump_done(struct netlink_callback *cb) +{ + struct rhashtable_iter *hti = (void *)cb->args[2]; + + if (cb->args[0] == 1) + rhashtable_walk_exit(hti); - return skb->len; + kfree(hti); + + return 0; } static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) @@ -172,6 +214,7 @@ static int netlink_diag_handler_dump(struct sk_buff *skb, struct nlmsghdr *h) if (h->nlmsg_flags & NLM_F_DUMP) { struct netlink_dump_control c = { .dump = netlink_diag_dump, + .done = netlink_diag_dump_done, }; return netlink_dump_start(net->diag_nlsk, skb, h, &c); } else