diff options
Diffstat (limited to 'net/tipc/link.c')
-rw-r--r-- | net/tipc/link.c | 170 |
1 files changed, 102 insertions, 68 deletions
diff --git a/net/tipc/link.c b/net/tipc/link.c index 75db07c78a69..ff9b0b92e62e 100644 --- a/net/tipc/link.c +++ b/net/tipc/link.c @@ -120,11 +120,21 @@ bool tipc_link_is_up(struct tipc_link *l) return link_is_up(l); } +bool tipc_link_peer_is_down(struct tipc_link *l) +{ + return l->state == LINK_PEER_RESET; +} + bool tipc_link_is_reset(struct tipc_link *l) { return l->state & (LINK_RESET | LINK_FAILINGOVER | LINK_ESTABLISHING); } +bool tipc_link_is_establishing(struct tipc_link *l) +{ + return l->state == LINK_ESTABLISHING; +} + bool tipc_link_is_synching(struct tipc_link *l) { return l->state == LINK_SYNCHING; @@ -321,14 +331,15 @@ int tipc_link_fsm_evt(struct tipc_link *l, int evt) switch (evt) { case LINK_ESTABLISH_EVT: l->state = LINK_ESTABLISHED; - rc |= TIPC_LINK_UP_EVT; break; case LINK_FAILOVER_BEGIN_EVT: l->state = LINK_FAILINGOVER; break; - case LINK_PEER_RESET_EVT: case LINK_RESET_EVT: + l->state = LINK_RESET; + break; case LINK_FAILURE_EVT: + case LINK_PEER_RESET_EVT: case LINK_SYNCH_BEGIN_EVT: case LINK_FAILOVER_END_EVT: break; @@ -578,8 +589,6 @@ void tipc_link_purge_queues(struct tipc_link *l_ptr) void tipc_link_reset(struct tipc_link *l) { - tipc_link_fsm_evt(l, LINK_RESET_EVT); - /* Link is down, accept any session */ l->peer_session = WILDCARD_SESSION; @@ -953,7 +962,7 @@ static bool tipc_data_input(struct tipc_link *link, struct sk_buff *skb, case TIPC_HIGH_IMPORTANCE: case TIPC_CRITICAL_IMPORTANCE: case CONN_MANAGER: - __skb_queue_tail(inputq, skb); + skb_queue_tail(inputq, skb); return true; case NAME_DISTRIBUTOR: node->bclink.recv_permitted = true; @@ -982,6 +991,7 @@ static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb, struct tipc_msg *hdr = buf_msg(skb); struct sk_buff **reasm_skb = &l->reasm_buf; struct sk_buff *iskb; + struct sk_buff_head tmpq; int usr = msg_user(hdr); int rc = 0; int pos = 0; @@ -1006,10 +1016,12 @@ static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb, } if (usr == MSG_BUNDLER) { + skb_queue_head_init(&tmpq); l->stats.recv_bundles++; l->stats.recv_bundled += msg_msgcnt(hdr); while (tipc_msg_extract(skb, &iskb, &pos)) - tipc_data_input(l, iskb, inputq); + tipc_data_input(l, iskb, &tmpq); + tipc_skb_queue_splice_tail(&tmpq, inputq); return 0; } else if (usr == MSG_FRAGMENTER) { l->stats.recv_fragments++; @@ -1044,49 +1056,76 @@ static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked) return released; } +/* tipc_link_build_ack_msg: prepare link acknowledge message for transmission + */ +void tipc_link_build_ack_msg(struct tipc_link *l, struct sk_buff_head *xmitq) +{ + l->rcv_unacked = 0; + l->stats.sent_acks++; + tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq); +} + +/* tipc_link_build_reset_msg: prepare link RESET or ACTIVATE message + */ +void tipc_link_build_reset_msg(struct tipc_link *l, struct sk_buff_head *xmitq) +{ + int mtyp = RESET_MSG; + + if (l->state == LINK_ESTABLISHING) + mtyp = ACTIVATE_MSG; + + tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq); +} + +/* tipc_link_build_nack_msg: prepare link nack message for transmission + */ +static void tipc_link_build_nack_msg(struct tipc_link *l, + struct sk_buff_head *xmitq) +{ + u32 def_cnt = ++l->stats.deferred_recv; + + if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV)) + tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq); +} + /* tipc_link_rcv - process TIPC packets/messages arriving from off-node - * @link: the link that should handle the message + * @l: the link that should handle the message * @skb: TIPC packet * @xmitq: queue to place packets to be sent after this call */ int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, struct sk_buff_head *xmitq) { - struct sk_buff_head *arrvq = &l->deferdq; - struct sk_buff_head tmpq; + struct sk_buff_head *defq = &l->deferdq; struct tipc_msg *hdr; - u16 seqno, rcv_nxt; + u16 seqno, rcv_nxt, win_lim; int rc = 0; - __skb_queue_head_init(&tmpq); - - if (unlikely(!__tipc_skb_queue_sorted(arrvq, skb))) { - if (!(skb_queue_len(arrvq) % TIPC_NACK_INTV)) - tipc_link_build_proto_msg(l, STATE_MSG, 0, - 0, 0, 0, xmitq); - return rc; - } - - while ((skb = skb_peek(arrvq))) { + do { hdr = buf_msg(skb); + seqno = msg_seqno(hdr); + rcv_nxt = l->rcv_nxt; + win_lim = rcv_nxt + TIPC_MAX_LINK_WIN; /* Verify and update link state */ - if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) { - __skb_dequeue(arrvq); - rc = tipc_link_proto_rcv(l, skb, xmitq); - continue; - } + if (unlikely(msg_user(hdr) == LINK_PROTOCOL)) + return tipc_link_proto_rcv(l, skb, xmitq); if (unlikely(!link_is_up(l))) { - rc = tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT); - if (!link_is_up(l)) { - kfree_skb(__skb_dequeue(arrvq)); - goto exit; - } + if (l->state == LINK_ESTABLISHING) + rc = TIPC_LINK_UP_EVT; + goto drop; } + /* Don't send probe at next timeout expiration */ l->silent_intv_cnt = 0; + /* Drop if outside receive window */ + if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) { + l->stats.duplicates++; + goto drop; + } + /* Forward queues and wake up waiting users */ if (likely(tipc_link_release_pkts(l, msg_ack(hdr)))) { tipc_link_advance_backlog(l, xmitq); @@ -1094,39 +1133,28 @@ int tipc_link_rcv(struct tipc_link *l, struct sk_buff *skb, link_prepare_wakeup(l); } - /* Defer reception if there is a gap in the sequence */ - seqno = msg_seqno(hdr); - rcv_nxt = l->rcv_nxt; - if (unlikely(less(rcv_nxt, seqno))) { - l->stats.deferred_recv++; - goto exit; - } - - __skb_dequeue(arrvq); - - /* Drop if packet already received */ - if (unlikely(more(rcv_nxt, seqno))) { - l->stats.duplicates++; - kfree_skb(skb); - goto exit; + /* Defer delivery if sequence gap */ + if (unlikely(seqno != rcv_nxt)) { + __tipc_skb_queue_sorted(defq, seqno, skb); + tipc_link_build_nack_msg(l, xmitq); + break; } - /* Packet can be delivered */ + /* Deliver packet */ l->rcv_nxt++; l->stats.recv_info++; - if (unlikely(!tipc_data_input(l, skb, &tmpq))) - rc = tipc_link_input(l, skb, &tmpq); + if (!tipc_data_input(l, skb, l->inputq)) + rc = tipc_link_input(l, skb, l->inputq); + if (unlikely(rc)) + break; + if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN)) + tipc_link_build_ack_msg(l, xmitq); + + } while ((skb = __skb_dequeue(defq))); - /* Ack at regular intervals */ - if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN)) { - l->rcv_unacked = 0; - l->stats.sent_acks++; - tipc_link_build_proto_msg(l, STATE_MSG, - 0, 0, 0, 0, xmitq); - } - } -exit: - tipc_skb_queue_splice_tail(&tmpq, l->inputq); + return rc; +drop: + kfree_skb(skb); return rc; } @@ -1250,7 +1278,7 @@ static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe, } /* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets - * with contents of the link's tranmsit and backlog queues. + * with contents of the link's transmit and backlog queues. */ void tipc_link_tnl_prepare(struct tipc_link *l, struct tipc_link *tnl, int mtyp, struct sk_buff_head *xmitq) @@ -1331,6 +1359,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, u16 peers_tol = msg_link_tolerance(hdr); u16 peers_prio = msg_linkprio(hdr); u16 rcv_nxt = l->rcv_nxt; + int mtyp = msg_type(hdr); char *if_name; int rc = 0; @@ -1340,7 +1369,7 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, if (link_own_addr(l) > msg_prevnode(hdr)) l->net_plane = msg_net_plane(hdr); - switch (msg_type(hdr)) { + switch (mtyp) { case RESET_MSG: /* Ignore duplicate RESET with old session number */ @@ -1367,12 +1396,14 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI)) l->priority = peers_prio; - if (msg_type(hdr) == RESET_MSG) { - rc |= tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); - } else if (!link_is_up(l)) { - tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); - rc |= tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT); - } + /* ACTIVATE_MSG serves as PEER_RESET if link is already down */ + if ((mtyp == RESET_MSG) || !link_is_up(l)) + rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); + + /* ACTIVATE_MSG takes up link if it was already locally reset */ + if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING)) + rc = TIPC_LINK_UP_EVT; + l->peer_session = msg_session(hdr); l->peer_bearer_id = msg_bearer_id(hdr); if (l->mtu > msg_max_pkt(hdr)) @@ -1389,9 +1420,12 @@ static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb, l->stats.recv_states++; if (msg_probe(hdr)) l->stats.recv_probes++; - rc = tipc_link_fsm_evt(l, LINK_ESTABLISH_EVT); - if (!link_is_up(l)) + + if (!link_is_up(l)) { + if (l->state == LINK_ESTABLISHING) + rc = TIPC_LINK_UP_EVT; break; + } /* Send NACK if peer has sent pkts we haven't received yet */ if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l)) |