diff options
Diffstat (limited to 'net/tipc/link.c')
-rw-r--r-- | net/tipc/link.c | 132 |
1 files changed, 72 insertions, 60 deletions
diff --git a/net/tipc/link.c b/net/tipc/link.c index ea32679..c052437 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -353,7 +353,6 @@ static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list) /* This really cannot happen... */ if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) { pr_warn("%s<%s>, send queue full", link_rst_msg, link->name); - tipc_link_reset(link); return -ENOBUFS; } /* Non-blocking sender: */ @@ -701,6 +700,78 @@ int __tipc_link_xmit(struct net *net, struct tipc_link *link, return 0; } +/** + * tipc_link_xmit(): enqueue buffer list according to queue situation + * @link: link to use + * @list: chain of buffers containing message + * @xmitq: returned list of packets to be sent by caller + * + * Consumes the buffer chain, except when returning -ELINKCONG, + * since the caller then may want to make more send attempts. + * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS + * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted + */ +int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list, + struct sk_buff_head *xmitq) +{ + struct tipc_msg *hdr = buf_msg(skb_peek(list)); + unsigned int maxwin = l->window; + unsigned int i, imp = msg_importance(hdr); + unsigned int mtu = l->mtu; + u16 ack = l->rcv_nxt - 1; + u16 seqno = l->snd_nxt; + u16 bc_last_in = l->owner->bclink.last_in; + struct sk_buff_head *transmq = &l->transmq; + struct sk_buff_head *backlogq = &l->backlogq; + struct sk_buff *skb, *_skb, *bskb; + + /* Match msg importance against this and all higher backlog limits: */ + for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) { + if (unlikely(l->backlog[i].len >= l->backlog[i].limit)) + return link_schedule_user(l, list); + } + if (unlikely(msg_size(hdr) > mtu)) + return -EMSGSIZE; + + /* Prepare each packet for sending, and add to relevant queue: */ + while (skb_queue_len(list)) { + skb = skb_peek(list); + hdr = buf_msg(skb); + msg_set_seqno(hdr, seqno); + msg_set_ack(hdr, ack); + msg_set_bcast_ack(hdr, bc_last_in); + + if (likely(skb_queue_len(transmq) < maxwin)) { + _skb = skb_clone(skb, GFP_ATOMIC); + if (!_skb) + return -ENOBUFS; + __skb_dequeue(list); + __skb_queue_tail(transmq, skb); + __skb_queue_tail(xmitq, _skb); + l->rcv_unacked = 0; + seqno++; + continue; + } + if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) { + kfree_skb(__skb_dequeue(list)); + l->stats.sent_bundled++; + continue; + } + if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) { + kfree_skb(__skb_dequeue(list)); + __skb_queue_tail(backlogq, bskb); + l->backlog[msg_importance(buf_msg(bskb))].len++; + l->stats.sent_bundled++; + l->stats.sent_bundles++; + continue; + } + l->backlog[imp].len += skb_queue_len(list); + skb_queue_splice_tail_init(list, backlogq); + } + l->snd_nxt = seqno; + return 0; +} + static void skb2list(struct sk_buff *skb, struct sk_buff_head *list) { skb_queue_head_init(list); @@ -715,65 +786,6 @@ static int __tipc_link_xmit_skb(struct tipc_link *link, struct sk_buff *skb) return __tipc_link_xmit(link->owner->net, link, &head); } -/* tipc_link_xmit_skb(): send single buffer to destination - * Buffers sent via this functon are generally TIPC_SYSTEM_IMPORTANCE - * messages, which will not cause link congestion - * The only exception is datagram messages rerouted after secondary - * lookup, which are rare and safe to dispose of anyway. - * TODO: Return real return value, and let callers use - * tipc_wait_for_sendpkt() where applicable - */ -int tipc_link_xmit_skb(struct net *net, struct sk_buff *skb, u32 dnode, - u32 selector) -{ - struct sk_buff_head head; - int rc; - - skb2list(skb, &head); - rc = tipc_link_xmit(net, &head, dnode, selector); - if (rc) - kfree_skb(skb); - return 0; -} - -/** - * tipc_link_xmit() is the general link level function for message sending - * @net: the applicable net namespace - * @list: chain of buffers containing message - * @dsz: amount of user data to be sent - * @dnode: address of destination node - * @selector: a number used for deterministic link selection - * Consumes the buffer chain, except when returning error - * Returns 0 if success, otherwise errno: -ELINKCONG,-EHOSTUNREACH,-EMSGSIZE - */ -int tipc_link_xmit(struct net *net, struct sk_buff_head *list, u32 dnode, - u32 selector) -{ - struct tipc_link *link = NULL; - struct tipc_node *node; - int rc = -EHOSTUNREACH; - - node = tipc_node_find(net, dnode); - if (node) { - tipc_node_lock(node); - link = node_active_link(node, selector & 1); - if (link) - rc = __tipc_link_xmit(net, link, list); - tipc_node_unlock(node); - tipc_node_put(node); - } - if (link) - return rc; - - if (likely(in_own_node(net, dnode))) { - tipc_sk_rcv(net, list); - return 0; - } - - __skb_queue_purge(list); - return rc; -} - /* * tipc_link_sync_xmit - synchronize broadcast link endpoints. * |