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-rw-r--r--net/tipc/link.c2285
1 files changed, 2285 insertions, 0 deletions
diff --git a/net/tipc/link.c b/net/tipc/link.c
new file mode 100644
index 000000000..0d2ee4eb1
--- /dev/null
+++ b/net/tipc/link.c
@@ -0,0 +1,2285 @@
+/*
+ * net/tipc/link.c: TIPC link code
+ *
+ * Copyright (c) 1996-2007, 2012-2016, Ericsson AB
+ * Copyright (c) 2004-2007, 2010-2013, Wind River Systems
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. Neither the names of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * Alternatively, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2 as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "core.h"
+#include "subscr.h"
+#include "link.h"
+#include "bcast.h"
+#include "socket.h"
+#include "name_distr.h"
+#include "discover.h"
+#include "netlink.h"
+#include "monitor.h"
+
+#include <linux/pkt_sched.h>
+
+struct tipc_stats {
+ u32 sent_pkts;
+ u32 recv_pkts;
+ u32 sent_states;
+ u32 recv_states;
+ u32 sent_probes;
+ u32 recv_probes;
+ u32 sent_nacks;
+ u32 recv_nacks;
+ u32 sent_acks;
+ u32 sent_bundled;
+ u32 sent_bundles;
+ u32 recv_bundled;
+ u32 recv_bundles;
+ u32 retransmitted;
+ u32 sent_fragmented;
+ u32 sent_fragments;
+ u32 recv_fragmented;
+ u32 recv_fragments;
+ u32 link_congs; /* # port sends blocked by congestion */
+ u32 deferred_recv;
+ u32 duplicates;
+ u32 max_queue_sz; /* send queue size high water mark */
+ u32 accu_queue_sz; /* used for send queue size profiling */
+ u32 queue_sz_counts; /* used for send queue size profiling */
+ u32 msg_length_counts; /* used for message length profiling */
+ u32 msg_lengths_total; /* used for message length profiling */
+ u32 msg_length_profile[7]; /* used for msg. length profiling */
+};
+
+/**
+ * struct tipc_link - TIPC link data structure
+ * @addr: network address of link's peer node
+ * @name: link name character string
+ * @media_addr: media address to use when sending messages over link
+ * @timer: link timer
+ * @net: pointer to namespace struct
+ * @refcnt: reference counter for permanent references (owner node & timer)
+ * @peer_session: link session # being used by peer end of link
+ * @peer_bearer_id: bearer id used by link's peer endpoint
+ * @bearer_id: local bearer id used by link
+ * @tolerance: minimum link continuity loss needed to reset link [in ms]
+ * @abort_limit: # of unacknowledged continuity probes needed to reset link
+ * @state: current state of link FSM
+ * @peer_caps: bitmap describing capabilities of peer node
+ * @silent_intv_cnt: # of timer intervals without any reception from peer
+ * @proto_msg: template for control messages generated by link
+ * @pmsg: convenience pointer to "proto_msg" field
+ * @priority: current link priority
+ * @net_plane: current link network plane ('A' through 'H')
+ * @mon_state: cookie with information needed by link monitor
+ * @backlog_limit: backlog queue congestion thresholds (indexed by importance)
+ * @exp_msg_count: # of tunnelled messages expected during link changeover
+ * @reset_rcv_checkpt: seq # of last acknowledged message at time of link reset
+ * @mtu: current maximum packet size for this link
+ * @advertised_mtu: advertised own mtu when link is being established
+ * @transmitq: queue for sent, non-acked messages
+ * @backlogq: queue for messages waiting to be sent
+ * @snt_nxt: next sequence number to use for outbound messages
+ * @last_retransmitted: sequence number of most recently retransmitted message
+ * @stale_cnt: counter for number of identical retransmit attempts
+ * @stale_limit: time when repeated identical retransmits must force link reset
+ * @ackers: # of peers that needs to ack each packet before it can be released
+ * @acked: # last packet acked by a certain peer. Used for broadcast.
+ * @rcv_nxt: next sequence number to expect for inbound messages
+ * @deferred_queue: deferred queue saved OOS b'cast message received from node
+ * @unacked_window: # of inbound messages rx'd without ack'ing back to peer
+ * @inputq: buffer queue for messages to be delivered upwards
+ * @namedq: buffer queue for name table messages to be delivered upwards
+ * @next_out: ptr to first unsent outbound message in queue
+ * @wakeupq: linked list of wakeup msgs waiting for link congestion to abate
+ * @long_msg_seq_no: next identifier to use for outbound fragmented messages
+ * @reasm_buf: head of partially reassembled inbound message fragments
+ * @bc_rcvr: marks that this is a broadcast receiver link
+ * @stats: collects statistics regarding link activity
+ */
+struct tipc_link {
+ u32 addr;
+ char name[TIPC_MAX_LINK_NAME];
+ struct net *net;
+
+ /* Management and link supervision data */
+ u16 peer_session;
+ u16 session;
+ u16 snd_nxt_state;
+ u16 rcv_nxt_state;
+ u32 peer_bearer_id;
+ u32 bearer_id;
+ u32 tolerance;
+ u32 abort_limit;
+ u32 state;
+ u16 peer_caps;
+ bool in_session;
+ bool active;
+ u32 silent_intv_cnt;
+ char if_name[TIPC_MAX_IF_NAME];
+ u32 priority;
+ char net_plane;
+ struct tipc_mon_state mon_state;
+ u16 rst_cnt;
+
+ /* Failover/synch */
+ u16 drop_point;
+ struct sk_buff *failover_reasm_skb;
+
+ /* Max packet negotiation */
+ u16 mtu;
+ u16 advertised_mtu;
+
+ /* Sending */
+ struct sk_buff_head transmq;
+ struct sk_buff_head backlogq;
+ struct {
+ u16 len;
+ u16 limit;
+ struct sk_buff *target_bskb;
+ } backlog[5];
+ u16 snd_nxt;
+ u16 last_retransm;
+ u16 window;
+ u16 stale_cnt;
+ unsigned long stale_limit;
+
+ /* Reception */
+ u16 rcv_nxt;
+ u32 rcv_unacked;
+ struct sk_buff_head deferdq;
+ struct sk_buff_head *inputq;
+ struct sk_buff_head *namedq;
+
+ /* Congestion handling */
+ struct sk_buff_head wakeupq;
+
+ /* Fragmentation/reassembly */
+ struct sk_buff *reasm_buf;
+
+ /* Broadcast */
+ u16 ackers;
+ u16 acked;
+ struct tipc_link *bc_rcvlink;
+ struct tipc_link *bc_sndlink;
+ unsigned long prev_retr;
+ u16 prev_from;
+ u16 prev_to;
+ u8 nack_state;
+ bool bc_peer_is_up;
+
+ /* Statistics */
+ struct tipc_stats stats;
+};
+
+/*
+ * Error message prefixes
+ */
+static const char *link_co_err = "Link tunneling error, ";
+static const char *link_rst_msg = "Resetting link ";
+
+/* Send states for broadcast NACKs
+ */
+enum {
+ BC_NACK_SND_CONDITIONAL,
+ BC_NACK_SND_UNCONDITIONAL,
+ BC_NACK_SND_SUPPRESS,
+};
+
+#define TIPC_BC_RETR_LIMIT 10 /* [ms] */
+
+/*
+ * Interval between NACKs when packets arrive out of order
+ */
+#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2)
+
+/* Link FSM states:
+ */
+enum {
+ LINK_ESTABLISHED = 0xe,
+ LINK_ESTABLISHING = 0xe << 4,
+ LINK_RESET = 0x1 << 8,
+ LINK_RESETTING = 0x2 << 12,
+ LINK_PEER_RESET = 0xd << 16,
+ LINK_FAILINGOVER = 0xf << 20,
+ LINK_SYNCHING = 0xc << 24
+};
+
+/* Link FSM state checking routines
+ */
+static int link_is_up(struct tipc_link *l)
+{
+ return l->state & (LINK_ESTABLISHED | LINK_SYNCHING);
+}
+
+static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
+ struct sk_buff_head *xmitq);
+static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
+ bool probe_reply, u16 rcvgap,
+ int tolerance, int priority,
+ struct sk_buff_head *xmitq);
+static void link_print(struct tipc_link *l, const char *str);
+static int tipc_link_build_nack_msg(struct tipc_link *l,
+ struct sk_buff_head *xmitq);
+static void tipc_link_build_bc_init_msg(struct tipc_link *l,
+ struct sk_buff_head *xmitq);
+static bool tipc_link_release_pkts(struct tipc_link *l, u16 to);
+
+/*
+ * Simple non-static link routines (i.e. referenced outside this file)
+ */
+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;
+}
+
+bool tipc_link_is_failingover(struct tipc_link *l)
+{
+ return l->state == LINK_FAILINGOVER;
+}
+
+bool tipc_link_is_blocked(struct tipc_link *l)
+{
+ return l->state & (LINK_RESETTING | LINK_PEER_RESET | LINK_FAILINGOVER);
+}
+
+static bool link_is_bc_sndlink(struct tipc_link *l)
+{
+ return !l->bc_sndlink;
+}
+
+static bool link_is_bc_rcvlink(struct tipc_link *l)
+{
+ return ((l->bc_rcvlink == l) && !link_is_bc_sndlink(l));
+}
+
+void tipc_link_set_active(struct tipc_link *l, bool active)
+{
+ l->active = active;
+}
+
+u32 tipc_link_id(struct tipc_link *l)
+{
+ return l->peer_bearer_id << 16 | l->bearer_id;
+}
+
+int tipc_link_window(struct tipc_link *l)
+{
+ return l->window;
+}
+
+int tipc_link_prio(struct tipc_link *l)
+{
+ return l->priority;
+}
+
+unsigned long tipc_link_tolerance(struct tipc_link *l)
+{
+ return l->tolerance;
+}
+
+struct sk_buff_head *tipc_link_inputq(struct tipc_link *l)
+{
+ return l->inputq;
+}
+
+char tipc_link_plane(struct tipc_link *l)
+{
+ return l->net_plane;
+}
+
+void tipc_link_update_caps(struct tipc_link *l, u16 capabilities)
+{
+ l->peer_caps = capabilities;
+}
+
+void tipc_link_add_bc_peer(struct tipc_link *snd_l,
+ struct tipc_link *uc_l,
+ struct sk_buff_head *xmitq)
+{
+ struct tipc_link *rcv_l = uc_l->bc_rcvlink;
+
+ snd_l->ackers++;
+ rcv_l->acked = snd_l->snd_nxt - 1;
+ snd_l->state = LINK_ESTABLISHED;
+ tipc_link_build_bc_init_msg(uc_l, xmitq);
+}
+
+void tipc_link_remove_bc_peer(struct tipc_link *snd_l,
+ struct tipc_link *rcv_l,
+ struct sk_buff_head *xmitq)
+{
+ u16 ack = snd_l->snd_nxt - 1;
+
+ snd_l->ackers--;
+ rcv_l->bc_peer_is_up = true;
+ rcv_l->state = LINK_ESTABLISHED;
+ tipc_link_bc_ack_rcv(rcv_l, ack, xmitq);
+ tipc_link_reset(rcv_l);
+ rcv_l->state = LINK_RESET;
+ if (!snd_l->ackers) {
+ tipc_link_reset(snd_l);
+ snd_l->state = LINK_RESET;
+ __skb_queue_purge(xmitq);
+ }
+}
+
+int tipc_link_bc_peers(struct tipc_link *l)
+{
+ return l->ackers;
+}
+
+static u16 link_bc_rcv_gap(struct tipc_link *l)
+{
+ struct sk_buff *skb = skb_peek(&l->deferdq);
+ u16 gap = 0;
+
+ if (more(l->snd_nxt, l->rcv_nxt))
+ gap = l->snd_nxt - l->rcv_nxt;
+ if (skb)
+ gap = buf_seqno(skb) - l->rcv_nxt;
+ return gap;
+}
+
+void tipc_link_set_mtu(struct tipc_link *l, int mtu)
+{
+ l->mtu = mtu;
+}
+
+int tipc_link_mtu(struct tipc_link *l)
+{
+ return l->mtu;
+}
+
+u16 tipc_link_rcv_nxt(struct tipc_link *l)
+{
+ return l->rcv_nxt;
+}
+
+u16 tipc_link_acked(struct tipc_link *l)
+{
+ return l->acked;
+}
+
+char *tipc_link_name(struct tipc_link *l)
+{
+ return l->name;
+}
+
+u32 tipc_link_state(struct tipc_link *l)
+{
+ return l->state;
+}
+
+/**
+ * tipc_link_create - create a new link
+ * @n: pointer to associated node
+ * @if_name: associated interface name
+ * @bearer_id: id (index) of associated bearer
+ * @tolerance: link tolerance to be used by link
+ * @net_plane: network plane (A,B,c..) this link belongs to
+ * @mtu: mtu to be advertised by link
+ * @priority: priority to be used by link
+ * @window: send window to be used by link
+ * @session: session to be used by link
+ * @ownnode: identity of own node
+ * @peer: node id of peer node
+ * @peer_caps: bitmap describing peer node capabilities
+ * @bc_sndlink: the namespace global link used for broadcast sending
+ * @bc_rcvlink: the peer specific link used for broadcast reception
+ * @inputq: queue to put messages ready for delivery
+ * @namedq: queue to put binding table update messages ready for delivery
+ * @link: return value, pointer to put the created link
+ *
+ * Returns true if link was created, otherwise false
+ */
+bool tipc_link_create(struct net *net, char *if_name, int bearer_id,
+ int tolerance, char net_plane, u32 mtu, int priority,
+ int window, u32 session, u32 self,
+ u32 peer, u8 *peer_id, u16 peer_caps,
+ struct tipc_link *bc_sndlink,
+ struct tipc_link *bc_rcvlink,
+ struct sk_buff_head *inputq,
+ struct sk_buff_head *namedq,
+ struct tipc_link **link)
+{
+ char peer_str[NODE_ID_STR_LEN] = {0,};
+ char self_str[NODE_ID_STR_LEN] = {0,};
+ struct tipc_link *l;
+
+ l = kzalloc(sizeof(*l), GFP_ATOMIC);
+ if (!l)
+ return false;
+ *link = l;
+ l->session = session;
+
+ /* Set link name for unicast links only */
+ if (peer_id) {
+ tipc_nodeid2string(self_str, tipc_own_id(net));
+ if (strlen(self_str) > 16)
+ sprintf(self_str, "%x", self);
+ tipc_nodeid2string(peer_str, peer_id);
+ if (strlen(peer_str) > 16)
+ sprintf(peer_str, "%x", peer);
+ }
+ /* Peer i/f name will be completed by reset/activate message */
+ snprintf(l->name, sizeof(l->name), "%s:%s-%s:unknown",
+ self_str, if_name, peer_str);
+
+ strcpy(l->if_name, if_name);
+ l->addr = peer;
+ l->peer_caps = peer_caps;
+ l->net = net;
+ l->in_session = false;
+ l->bearer_id = bearer_id;
+ l->tolerance = tolerance;
+ if (bc_rcvlink)
+ bc_rcvlink->tolerance = tolerance;
+ l->net_plane = net_plane;
+ l->advertised_mtu = mtu;
+ l->mtu = mtu;
+ l->priority = priority;
+ tipc_link_set_queue_limits(l, window);
+ l->ackers = 1;
+ l->bc_sndlink = bc_sndlink;
+ l->bc_rcvlink = bc_rcvlink;
+ l->inputq = inputq;
+ l->namedq = namedq;
+ l->state = LINK_RESETTING;
+ __skb_queue_head_init(&l->transmq);
+ __skb_queue_head_init(&l->backlogq);
+ __skb_queue_head_init(&l->deferdq);
+ skb_queue_head_init(&l->wakeupq);
+ skb_queue_head_init(l->inputq);
+ return true;
+}
+
+/**
+ * tipc_link_bc_create - create new link to be used for broadcast
+ * @n: pointer to associated node
+ * @mtu: mtu to be used initially if no peers
+ * @window: send window to be used
+ * @inputq: queue to put messages ready for delivery
+ * @namedq: queue to put binding table update messages ready for delivery
+ * @link: return value, pointer to put the created link
+ *
+ * Returns true if link was created, otherwise false
+ */
+bool tipc_link_bc_create(struct net *net, u32 ownnode, u32 peer,
+ int mtu, int window, u16 peer_caps,
+ struct sk_buff_head *inputq,
+ struct sk_buff_head *namedq,
+ struct tipc_link *bc_sndlink,
+ struct tipc_link **link)
+{
+ struct tipc_link *l;
+
+ if (!tipc_link_create(net, "", MAX_BEARERS, 0, 'Z', mtu, 0, window,
+ 0, ownnode, peer, NULL, peer_caps, bc_sndlink,
+ NULL, inputq, namedq, link))
+ return false;
+
+ l = *link;
+ strcpy(l->name, tipc_bclink_name);
+ tipc_link_reset(l);
+ l->state = LINK_RESET;
+ l->ackers = 0;
+ l->bc_rcvlink = l;
+
+ /* Broadcast send link is always up */
+ if (link_is_bc_sndlink(l))
+ l->state = LINK_ESTABLISHED;
+
+ /* Disable replicast if even a single peer doesn't support it */
+ if (link_is_bc_rcvlink(l) && !(peer_caps & TIPC_BCAST_RCAST))
+ tipc_bcast_disable_rcast(net);
+
+ return true;
+}
+
+/**
+ * tipc_link_fsm_evt - link finite state machine
+ * @l: pointer to link
+ * @evt: state machine event to be processed
+ */
+int tipc_link_fsm_evt(struct tipc_link *l, int evt)
+{
+ int rc = 0;
+
+ switch (l->state) {
+ case LINK_RESETTING:
+ switch (evt) {
+ case LINK_PEER_RESET_EVT:
+ l->state = LINK_PEER_RESET;
+ break;
+ case LINK_RESET_EVT:
+ l->state = LINK_RESET;
+ break;
+ case LINK_FAILURE_EVT:
+ case LINK_FAILOVER_BEGIN_EVT:
+ case LINK_ESTABLISH_EVT:
+ case LINK_FAILOVER_END_EVT:
+ case LINK_SYNCH_BEGIN_EVT:
+ case LINK_SYNCH_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ case LINK_RESET:
+ switch (evt) {
+ case LINK_PEER_RESET_EVT:
+ l->state = LINK_ESTABLISHING;
+ break;
+ case LINK_FAILOVER_BEGIN_EVT:
+ l->state = LINK_FAILINGOVER;
+ case LINK_FAILURE_EVT:
+ case LINK_RESET_EVT:
+ case LINK_ESTABLISH_EVT:
+ case LINK_FAILOVER_END_EVT:
+ break;
+ case LINK_SYNCH_BEGIN_EVT:
+ case LINK_SYNCH_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ case LINK_PEER_RESET:
+ switch (evt) {
+ case LINK_RESET_EVT:
+ l->state = LINK_ESTABLISHING;
+ break;
+ case LINK_PEER_RESET_EVT:
+ case LINK_ESTABLISH_EVT:
+ case LINK_FAILURE_EVT:
+ break;
+ case LINK_SYNCH_BEGIN_EVT:
+ case LINK_SYNCH_END_EVT:
+ case LINK_FAILOVER_BEGIN_EVT:
+ case LINK_FAILOVER_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ case LINK_FAILINGOVER:
+ switch (evt) {
+ case LINK_FAILOVER_END_EVT:
+ l->state = LINK_RESET;
+ break;
+ case LINK_PEER_RESET_EVT:
+ case LINK_RESET_EVT:
+ case LINK_ESTABLISH_EVT:
+ case LINK_FAILURE_EVT:
+ break;
+ case LINK_FAILOVER_BEGIN_EVT:
+ case LINK_SYNCH_BEGIN_EVT:
+ case LINK_SYNCH_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ case LINK_ESTABLISHING:
+ switch (evt) {
+ case LINK_ESTABLISH_EVT:
+ l->state = LINK_ESTABLISHED;
+ break;
+ case LINK_FAILOVER_BEGIN_EVT:
+ l->state = LINK_FAILINGOVER;
+ break;
+ 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;
+ case LINK_SYNCH_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ case LINK_ESTABLISHED:
+ switch (evt) {
+ case LINK_PEER_RESET_EVT:
+ l->state = LINK_PEER_RESET;
+ rc |= TIPC_LINK_DOWN_EVT;
+ break;
+ case LINK_FAILURE_EVT:
+ l->state = LINK_RESETTING;
+ rc |= TIPC_LINK_DOWN_EVT;
+ break;
+ case LINK_RESET_EVT:
+ l->state = LINK_RESET;
+ break;
+ case LINK_ESTABLISH_EVT:
+ case LINK_SYNCH_END_EVT:
+ break;
+ case LINK_SYNCH_BEGIN_EVT:
+ l->state = LINK_SYNCHING;
+ break;
+ case LINK_FAILOVER_BEGIN_EVT:
+ case LINK_FAILOVER_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ case LINK_SYNCHING:
+ switch (evt) {
+ case LINK_PEER_RESET_EVT:
+ l->state = LINK_PEER_RESET;
+ rc |= TIPC_LINK_DOWN_EVT;
+ break;
+ case LINK_FAILURE_EVT:
+ l->state = LINK_RESETTING;
+ rc |= TIPC_LINK_DOWN_EVT;
+ break;
+ case LINK_RESET_EVT:
+ l->state = LINK_RESET;
+ break;
+ case LINK_ESTABLISH_EVT:
+ case LINK_SYNCH_BEGIN_EVT:
+ break;
+ case LINK_SYNCH_END_EVT:
+ l->state = LINK_ESTABLISHED;
+ break;
+ case LINK_FAILOVER_BEGIN_EVT:
+ case LINK_FAILOVER_END_EVT:
+ default:
+ goto illegal_evt;
+ }
+ break;
+ default:
+ pr_err("Unknown FSM state %x in %s\n", l->state, l->name);
+ }
+ return rc;
+illegal_evt:
+ pr_err("Illegal FSM event %x in state %x on link %s\n",
+ evt, l->state, l->name);
+ return rc;
+}
+
+/* link_profile_stats - update statistical profiling of traffic
+ */
+static void link_profile_stats(struct tipc_link *l)
+{
+ struct sk_buff *skb;
+ struct tipc_msg *msg;
+ int length;
+
+ /* Update counters used in statistical profiling of send traffic */
+ l->stats.accu_queue_sz += skb_queue_len(&l->transmq);
+ l->stats.queue_sz_counts++;
+
+ skb = skb_peek(&l->transmq);
+ if (!skb)
+ return;
+ msg = buf_msg(skb);
+ length = msg_size(msg);
+
+ if (msg_user(msg) == MSG_FRAGMENTER) {
+ if (msg_type(msg) != FIRST_FRAGMENT)
+ return;
+ length = msg_size(msg_get_wrapped(msg));
+ }
+ l->stats.msg_lengths_total += length;
+ l->stats.msg_length_counts++;
+ if (length <= 64)
+ l->stats.msg_length_profile[0]++;
+ else if (length <= 256)
+ l->stats.msg_length_profile[1]++;
+ else if (length <= 1024)
+ l->stats.msg_length_profile[2]++;
+ else if (length <= 4096)
+ l->stats.msg_length_profile[3]++;
+ else if (length <= 16384)
+ l->stats.msg_length_profile[4]++;
+ else if (length <= 32768)
+ l->stats.msg_length_profile[5]++;
+ else
+ l->stats.msg_length_profile[6]++;
+}
+
+/* tipc_link_timeout - perform periodic task as instructed from node timeout
+ */
+int tipc_link_timeout(struct tipc_link *l, struct sk_buff_head *xmitq)
+{
+ int mtyp = 0;
+ int rc = 0;
+ bool state = false;
+ bool probe = false;
+ bool setup = false;
+ u16 bc_snt = l->bc_sndlink->snd_nxt - 1;
+ u16 bc_acked = l->bc_rcvlink->acked;
+ struct tipc_mon_state *mstate = &l->mon_state;
+
+ switch (l->state) {
+ case LINK_ESTABLISHED:
+ case LINK_SYNCHING:
+ mtyp = STATE_MSG;
+ link_profile_stats(l);
+ tipc_mon_get_state(l->net, l->addr, mstate, l->bearer_id);
+ if (mstate->reset || (l->silent_intv_cnt > l->abort_limit))
+ return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ state = bc_acked != bc_snt;
+ state |= l->bc_rcvlink->rcv_unacked;
+ state |= l->rcv_unacked;
+ state |= !skb_queue_empty(&l->transmq);
+ state |= !skb_queue_empty(&l->deferdq);
+ probe = mstate->probing;
+ probe |= l->silent_intv_cnt;
+ if (probe || mstate->monitoring)
+ l->silent_intv_cnt++;
+ break;
+ case LINK_RESET:
+ setup = l->rst_cnt++ <= 4;
+ setup |= !(l->rst_cnt % 16);
+ mtyp = RESET_MSG;
+ break;
+ case LINK_ESTABLISHING:
+ setup = true;
+ mtyp = ACTIVATE_MSG;
+ break;
+ case LINK_PEER_RESET:
+ case LINK_RESETTING:
+ case LINK_FAILINGOVER:
+ break;
+ default:
+ break;
+ }
+
+ if (state || probe || setup)
+ tipc_link_build_proto_msg(l, mtyp, probe, 0, 0, 0, 0, xmitq);
+
+ return rc;
+}
+
+/**
+ * link_schedule_user - schedule a message sender for wakeup after congestion
+ * @l: congested link
+ * @hdr: header of message that is being sent
+ * Create pseudo msg to send back to user when congestion abates
+ */
+static int link_schedule_user(struct tipc_link *l, struct tipc_msg *hdr)
+{
+ u32 dnode = tipc_own_addr(l->net);
+ u32 dport = msg_origport(hdr);
+ struct sk_buff *skb;
+
+ /* Create and schedule wakeup pseudo message */
+ skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0,
+ dnode, l->addr, dport, 0, 0);
+ if (!skb)
+ return -ENOBUFS;
+ msg_set_dest_droppable(buf_msg(skb), true);
+ TIPC_SKB_CB(skb)->chain_imp = msg_importance(hdr);
+ skb_queue_tail(&l->wakeupq, skb);
+ l->stats.link_congs++;
+ return -ELINKCONG;
+}
+
+/**
+ * link_prepare_wakeup - prepare users for wakeup after congestion
+ * @l: congested link
+ * Wake up a number of waiting users, as permitted by available space
+ * in the send queue
+ */
+static void link_prepare_wakeup(struct tipc_link *l)
+{
+ struct sk_buff_head *wakeupq = &l->wakeupq;
+ struct sk_buff_head *inputq = l->inputq;
+ struct sk_buff *skb, *tmp;
+ struct sk_buff_head tmpq;
+ int avail[5] = {0,};
+ int imp = 0;
+
+ __skb_queue_head_init(&tmpq);
+
+ for (; imp <= TIPC_SYSTEM_IMPORTANCE; imp++)
+ avail[imp] = l->backlog[imp].limit - l->backlog[imp].len;
+
+ skb_queue_walk_safe(wakeupq, skb, tmp) {
+ imp = TIPC_SKB_CB(skb)->chain_imp;
+ if (avail[imp] <= 0)
+ continue;
+ avail[imp]--;
+ __skb_unlink(skb, wakeupq);
+ __skb_queue_tail(&tmpq, skb);
+ }
+
+ spin_lock_bh(&inputq->lock);
+ skb_queue_splice_tail(&tmpq, inputq);
+ spin_unlock_bh(&inputq->lock);
+
+}
+
+void tipc_link_reset(struct tipc_link *l)
+{
+ struct sk_buff_head list;
+ u32 imp;
+
+ __skb_queue_head_init(&list);
+
+ l->in_session = false;
+ l->session++;
+ l->mtu = l->advertised_mtu;
+
+ spin_lock_bh(&l->wakeupq.lock);
+ skb_queue_splice_init(&l->wakeupq, &list);
+ spin_unlock_bh(&l->wakeupq.lock);
+
+ spin_lock_bh(&l->inputq->lock);
+ skb_queue_splice_init(&list, l->inputq);
+ spin_unlock_bh(&l->inputq->lock);
+
+ __skb_queue_purge(&l->transmq);
+ __skb_queue_purge(&l->deferdq);
+ __skb_queue_purge(&l->backlogq);
+ for (imp = 0; imp <= TIPC_SYSTEM_IMPORTANCE; imp++) {
+ l->backlog[imp].len = 0;
+ l->backlog[imp].target_bskb = NULL;
+ }
+ kfree_skb(l->reasm_buf);
+ kfree_skb(l->failover_reasm_skb);
+ l->reasm_buf = NULL;
+ l->failover_reasm_skb = NULL;
+ l->rcv_unacked = 0;
+ l->snd_nxt = 1;
+ l->rcv_nxt = 1;
+ l->snd_nxt_state = 1;
+ l->rcv_nxt_state = 1;
+ l->acked = 0;
+ l->silent_intv_cnt = 0;
+ l->rst_cnt = 0;
+ l->stale_cnt = 0;
+ l->bc_peer_is_up = false;
+ memset(&l->mon_state, 0, sizeof(l->mon_state));
+ tipc_link_reset_stats(l);
+}
+
+/**
+ * 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.
+ * 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)
+{
+ unsigned int maxwin = l->window;
+ unsigned int mtu = l->mtu;
+ u16 ack = l->rcv_nxt - 1;
+ u16 seqno = l->snd_nxt;
+ u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
+ struct sk_buff_head *transmq = &l->transmq;
+ struct sk_buff_head *backlogq = &l->backlogq;
+ struct sk_buff *skb, *_skb, **tskb;
+ int pkt_cnt = skb_queue_len(list);
+ struct tipc_msg *hdr;
+ int rc = 0;
+ int imp;
+
+ if (pkt_cnt <= 0)
+ return 0;
+
+ hdr = buf_msg(skb_peek(list));
+ if (unlikely(msg_size(hdr) > mtu)) {
+ __skb_queue_purge(list);
+ return -EMSGSIZE;
+ }
+
+ imp = msg_importance(hdr);
+ /* Allow oversubscription of one data msg per source at congestion */
+ if (unlikely(l->backlog[imp].len >= l->backlog[imp].limit)) {
+ if (imp == TIPC_SYSTEM_IMPORTANCE) {
+ pr_warn("%s<%s>, link overflow", link_rst_msg, l->name);
+ return -ENOBUFS;
+ }
+ rc = link_schedule_user(l, hdr);
+ }
+
+ if (pkt_cnt > 1) {
+ l->stats.sent_fragmented++;
+ l->stats.sent_fragments += pkt_cnt;
+ }
+
+ /* 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_ack);
+
+ if (likely(skb_queue_len(transmq) < maxwin)) {
+ _skb = skb_clone(skb, GFP_ATOMIC);
+ if (!_skb) {
+ __skb_queue_purge(list);
+ return -ENOBUFS;
+ }
+ __skb_dequeue(list);
+ __skb_queue_tail(transmq, skb);
+ __skb_queue_tail(xmitq, _skb);
+ TIPC_SKB_CB(skb)->ackers = l->ackers;
+ l->rcv_unacked = 0;
+ l->stats.sent_pkts++;
+ seqno++;
+ continue;
+ }
+ tskb = &l->backlog[imp].target_bskb;
+ if (tipc_msg_bundle(*tskb, hdr, mtu)) {
+ kfree_skb(__skb_dequeue(list));
+ l->stats.sent_bundled++;
+ continue;
+ }
+ if (tipc_msg_make_bundle(tskb, hdr, mtu, l->addr)) {
+ kfree_skb(__skb_dequeue(list));
+ __skb_queue_tail(backlogq, *tskb);
+ l->backlog[imp].len++;
+ l->stats.sent_bundled++;
+ l->stats.sent_bundles++;
+ continue;
+ }
+ l->backlog[imp].target_bskb = NULL;
+ l->backlog[imp].len += skb_queue_len(list);
+ skb_queue_splice_tail_init(list, backlogq);
+ }
+ l->snd_nxt = seqno;
+ return rc;
+}
+
+static void tipc_link_advance_backlog(struct tipc_link *l,
+ struct sk_buff_head *xmitq)
+{
+ struct sk_buff *skb, *_skb;
+ struct tipc_msg *hdr;
+ u16 seqno = l->snd_nxt;
+ u16 ack = l->rcv_nxt - 1;
+ u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
+ u32 imp;
+
+ while (skb_queue_len(&l->transmq) < l->window) {
+ skb = skb_peek(&l->backlogq);
+ if (!skb)
+ break;
+ _skb = skb_clone(skb, GFP_ATOMIC);
+ if (!_skb)
+ break;
+ __skb_dequeue(&l->backlogq);
+ hdr = buf_msg(skb);
+ imp = msg_importance(hdr);
+ l->backlog[imp].len--;
+ if (unlikely(skb == l->backlog[imp].target_bskb))
+ l->backlog[imp].target_bskb = NULL;
+ __skb_queue_tail(&l->transmq, skb);
+ __skb_queue_tail(xmitq, _skb);
+ TIPC_SKB_CB(skb)->ackers = l->ackers;
+ msg_set_seqno(hdr, seqno);
+ msg_set_ack(hdr, ack);
+ msg_set_bcast_ack(hdr, bc_ack);
+ l->rcv_unacked = 0;
+ l->stats.sent_pkts++;
+ seqno++;
+ }
+ l->snd_nxt = seqno;
+}
+
+static void link_retransmit_failure(struct tipc_link *l, struct sk_buff *skb)
+{
+ struct tipc_msg *hdr = buf_msg(skb);
+
+ pr_warn("Retransmission failure on link <%s>\n", l->name);
+ link_print(l, "State of link ");
+ pr_info("Failed msg: usr %u, typ %u, len %u, err %u\n",
+ msg_user(hdr), msg_type(hdr), msg_size(hdr), msg_errcode(hdr));
+ pr_info("sqno %u, prev: %x, src: %x\n",
+ msg_seqno(hdr), msg_prevnode(hdr), msg_orignode(hdr));
+}
+
+/* tipc_link_retrans() - retransmit one or more packets
+ * @l: the link to transmit on
+ * @r: the receiving link ordering the retransmit. Same as l if unicast
+ * @from: retransmit from (inclusive) this sequence number
+ * @to: retransmit to (inclusive) this sequence number
+ * xmitq: queue for accumulating the retransmitted packets
+ */
+static int tipc_link_retrans(struct tipc_link *l, struct tipc_link *r,
+ u16 from, u16 to, struct sk_buff_head *xmitq)
+{
+ struct sk_buff *_skb, *skb = skb_peek(&l->transmq);
+ u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
+ u16 ack = l->rcv_nxt - 1;
+ struct tipc_msg *hdr;
+
+ if (!skb)
+ return 0;
+
+ /* Detect repeated retransmit failures on same packet */
+ if (r->last_retransm != buf_seqno(skb)) {
+ r->last_retransm = buf_seqno(skb);
+ r->stale_limit = jiffies + msecs_to_jiffies(r->tolerance);
+ r->stale_cnt = 0;
+ } else if (++r->stale_cnt > 99 && time_after(jiffies, r->stale_limit)) {
+ link_retransmit_failure(l, skb);
+ if (link_is_bc_sndlink(l))
+ return TIPC_LINK_DOWN_EVT;
+ return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ }
+
+ skb_queue_walk(&l->transmq, skb) {
+ hdr = buf_msg(skb);
+ if (less(msg_seqno(hdr), from))
+ continue;
+ if (more(msg_seqno(hdr), to))
+ break;
+ _skb = __pskb_copy(skb, MIN_H_SIZE, GFP_ATOMIC);
+ if (!_skb)
+ return 0;
+ hdr = buf_msg(_skb);
+ msg_set_ack(hdr, ack);
+ msg_set_bcast_ack(hdr, bc_ack);
+ _skb->priority = TC_PRIO_CONTROL;
+ __skb_queue_tail(xmitq, _skb);
+ l->stats.retransmitted++;
+ }
+ return 0;
+}
+
+/* tipc_data_input - deliver data and name distr msgs to upper layer
+ *
+ * Consumes buffer if message is of right type
+ * Node lock must be held
+ */
+static bool tipc_data_input(struct tipc_link *l, struct sk_buff *skb,
+ struct sk_buff_head *inputq)
+{
+ struct sk_buff_head *mc_inputq = l->bc_rcvlink->inputq;
+ struct tipc_msg *hdr = buf_msg(skb);
+
+ switch (msg_user(hdr)) {
+ case TIPC_LOW_IMPORTANCE:
+ case TIPC_MEDIUM_IMPORTANCE:
+ case TIPC_HIGH_IMPORTANCE:
+ case TIPC_CRITICAL_IMPORTANCE:
+ if (unlikely(msg_in_group(hdr) || msg_mcast(hdr))) {
+ skb_queue_tail(mc_inputq, skb);
+ return true;
+ }
+ /* else: fall through */
+ case CONN_MANAGER:
+ skb_queue_tail(inputq, skb);
+ return true;
+ case GROUP_PROTOCOL:
+ skb_queue_tail(mc_inputq, skb);
+ return true;
+ case NAME_DISTRIBUTOR:
+ l->bc_rcvlink->state = LINK_ESTABLISHED;
+ skb_queue_tail(l->namedq, skb);
+ return true;
+ case MSG_BUNDLER:
+ case TUNNEL_PROTOCOL:
+ case MSG_FRAGMENTER:
+ case BCAST_PROTOCOL:
+ return false;
+ default:
+ pr_warn("Dropping received illegal msg type\n");
+ kfree_skb(skb);
+ return true;
+ };
+}
+
+/* tipc_link_input - process packet that has passed link protocol check
+ *
+ * Consumes buffer
+ */
+static int tipc_link_input(struct tipc_link *l, struct sk_buff *skb,
+ struct sk_buff_head *inputq)
+{
+ 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;
+ int ipos = 0;
+
+ if (unlikely(usr == TUNNEL_PROTOCOL)) {
+ if (msg_type(hdr) == SYNCH_MSG) {
+ __skb_queue_purge(&l->deferdq);
+ goto drop;
+ }
+ if (!tipc_msg_extract(skb, &iskb, &ipos))
+ return rc;
+ kfree_skb(skb);
+ skb = iskb;
+ hdr = buf_msg(skb);
+ if (less(msg_seqno(hdr), l->drop_point))
+ goto drop;
+ if (tipc_data_input(l, skb, inputq))
+ return rc;
+ usr = msg_user(hdr);
+ reasm_skb = &l->failover_reasm_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, &tmpq);
+ tipc_skb_queue_splice_tail(&tmpq, inputq);
+ return 0;
+ } else if (usr == MSG_FRAGMENTER) {
+ l->stats.recv_fragments++;
+ if (tipc_buf_append(reasm_skb, &skb)) {
+ l->stats.recv_fragmented++;
+ tipc_data_input(l, skb, inputq);
+ } else if (!*reasm_skb && !link_is_bc_rcvlink(l)) {
+ pr_warn_ratelimited("Unable to build fragment list\n");
+ return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ }
+ return 0;
+ } else if (usr == BCAST_PROTOCOL) {
+ tipc_bcast_lock(l->net);
+ tipc_link_bc_init_rcv(l->bc_rcvlink, hdr);
+ tipc_bcast_unlock(l->net);
+ }
+drop:
+ kfree_skb(skb);
+ return 0;
+}
+
+static bool tipc_link_release_pkts(struct tipc_link *l, u16 acked)
+{
+ bool released = false;
+ struct sk_buff *skb, *tmp;
+
+ skb_queue_walk_safe(&l->transmq, skb, tmp) {
+ if (more(buf_seqno(skb), acked))
+ break;
+ __skb_unlink(skb, &l->transmq);
+ kfree_skb(skb);
+ released = true;
+ }
+ return released;
+}
+
+/* tipc_link_build_state_msg: prepare link state message for transmission
+ *
+ * Note that sending of broadcast ack is coordinated among nodes, to reduce
+ * risk of ack storms towards the sender
+ */
+int tipc_link_build_state_msg(struct tipc_link *l, struct sk_buff_head *xmitq)
+{
+ if (!l)
+ return 0;
+
+ /* Broadcast ACK must be sent via a unicast link => defer to caller */
+ if (link_is_bc_rcvlink(l)) {
+ if (((l->rcv_nxt ^ tipc_own_addr(l->net)) & 0xf) != 0xf)
+ return 0;
+ l->rcv_unacked = 0;
+
+ /* Use snd_nxt to store peer's snd_nxt in broadcast rcv link */
+ l->snd_nxt = l->rcv_nxt;
+ return TIPC_LINK_SND_STATE;
+ }
+
+ /* Unicast ACK */
+ l->rcv_unacked = 0;
+ l->stats.sent_acks++;
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
+ return 0;
+}
+
+/* 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;
+ struct sk_buff *skb;
+
+ if (l->state == LINK_ESTABLISHING)
+ mtyp = ACTIVATE_MSG;
+
+ tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, 0, xmitq);
+
+ /* Inform peer that this endpoint is going down if applicable */
+ skb = skb_peek_tail(xmitq);
+ if (skb && (l->state == LINK_RESET))
+ msg_set_peer_stopping(buf_msg(skb), 1);
+}
+
+/* tipc_link_build_nack_msg: prepare link nack message for transmission
+ * Note that sending of broadcast NACK is coordinated among nodes, to
+ * reduce the risk of NACK storms towards the sender
+ */
+static int tipc_link_build_nack_msg(struct tipc_link *l,
+ struct sk_buff_head *xmitq)
+{
+ u32 def_cnt = ++l->stats.deferred_recv;
+ int match1, match2;
+
+ if (link_is_bc_rcvlink(l)) {
+ match1 = def_cnt & 0xf;
+ match2 = tipc_own_addr(l->net) & 0xf;
+ if (match1 == match2)
+ return TIPC_LINK_SND_STATE;
+ return 0;
+ }
+
+ if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV))
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, 0, xmitq);
+ return 0;
+}
+
+/* tipc_link_rcv - process TIPC packets/messages arriving from off-node
+ * @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 *defq = &l->deferdq;
+ struct tipc_msg *hdr;
+ u16 seqno, rcv_nxt, win_lim;
+ int rc = 0;
+
+ 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))
+ return tipc_link_proto_rcv(l, skb, xmitq);
+
+ if (unlikely(!link_is_up(l))) {
+ 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)))) {
+ l->stale_cnt = 0;
+ tipc_link_advance_backlog(l, xmitq);
+ if (unlikely(!skb_queue_empty(&l->wakeupq)))
+ link_prepare_wakeup(l);
+ }
+
+ /* Defer delivery if sequence gap */
+ if (unlikely(seqno != rcv_nxt)) {
+ __tipc_skb_queue_sorted(defq, seqno, skb);
+ rc |= tipc_link_build_nack_msg(l, xmitq);
+ break;
+ }
+
+ /* Deliver packet */
+ l->rcv_nxt++;
+ l->stats.recv_pkts++;
+ if (!tipc_data_input(l, skb, l->inputq))
+ rc |= tipc_link_input(l, skb, l->inputq);
+ if (unlikely(++l->rcv_unacked >= TIPC_MIN_LINK_WIN))
+ rc |= tipc_link_build_state_msg(l, xmitq);
+ if (unlikely(rc & ~TIPC_LINK_SND_STATE))
+ break;
+ } while ((skb = __skb_dequeue(defq)));
+
+ return rc;
+drop:
+ kfree_skb(skb);
+ return rc;
+}
+
+static void tipc_link_build_proto_msg(struct tipc_link *l, int mtyp, bool probe,
+ bool probe_reply, u16 rcvgap,
+ int tolerance, int priority,
+ struct sk_buff_head *xmitq)
+{
+ struct tipc_link *bcl = l->bc_rcvlink;
+ struct sk_buff *skb;
+ struct tipc_msg *hdr;
+ struct sk_buff_head *dfq = &l->deferdq;
+ bool node_up = link_is_up(bcl);
+ struct tipc_mon_state *mstate = &l->mon_state;
+ int dlen = 0;
+ void *data;
+
+ /* Don't send protocol message during reset or link failover */
+ if (tipc_link_is_blocked(l))
+ return;
+
+ if (!tipc_link_is_up(l) && (mtyp == STATE_MSG))
+ return;
+
+ if (!skb_queue_empty(dfq))
+ rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
+
+ skb = tipc_msg_create(LINK_PROTOCOL, mtyp, INT_H_SIZE,
+ tipc_max_domain_size, l->addr,
+ tipc_own_addr(l->net), 0, 0, 0);
+ if (!skb)
+ return;
+
+ hdr = buf_msg(skb);
+ data = msg_data(hdr);
+ msg_set_session(hdr, l->session);
+ msg_set_bearer_id(hdr, l->bearer_id);
+ msg_set_net_plane(hdr, l->net_plane);
+ msg_set_next_sent(hdr, l->snd_nxt);
+ msg_set_ack(hdr, l->rcv_nxt - 1);
+ msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
+ msg_set_bc_ack_invalid(hdr, !node_up);
+ msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
+ msg_set_link_tolerance(hdr, tolerance);
+ msg_set_linkprio(hdr, priority);
+ msg_set_redundant_link(hdr, node_up);
+ msg_set_seq_gap(hdr, 0);
+ msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2);
+
+ if (mtyp == STATE_MSG) {
+ if (l->peer_caps & TIPC_LINK_PROTO_SEQNO)
+ msg_set_seqno(hdr, l->snd_nxt_state++);
+ msg_set_seq_gap(hdr, rcvgap);
+ msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
+ msg_set_probe(hdr, probe);
+ msg_set_is_keepalive(hdr, probe || probe_reply);
+ tipc_mon_prep(l->net, data, &dlen, mstate, l->bearer_id);
+ msg_set_size(hdr, INT_H_SIZE + dlen);
+ skb_trim(skb, INT_H_SIZE + dlen);
+ l->stats.sent_states++;
+ l->rcv_unacked = 0;
+ } else {
+ /* RESET_MSG or ACTIVATE_MSG */
+ msg_set_max_pkt(hdr, l->advertised_mtu);
+ strcpy(data, l->if_name);
+ msg_set_size(hdr, INT_H_SIZE + TIPC_MAX_IF_NAME);
+ skb_trim(skb, INT_H_SIZE + TIPC_MAX_IF_NAME);
+ }
+ if (probe)
+ l->stats.sent_probes++;
+ if (rcvgap)
+ l->stats.sent_nacks++;
+ skb->priority = TC_PRIO_CONTROL;
+ __skb_queue_tail(xmitq, skb);
+}
+
+void tipc_link_create_dummy_tnl_msg(struct tipc_link *l,
+ struct sk_buff_head *xmitq)
+{
+ u32 onode = tipc_own_addr(l->net);
+ struct tipc_msg *hdr, *ihdr;
+ struct sk_buff_head tnlq;
+ struct sk_buff *skb;
+ u32 dnode = l->addr;
+
+ __skb_queue_head_init(&tnlq);
+ skb = tipc_msg_create(TUNNEL_PROTOCOL, FAILOVER_MSG,
+ INT_H_SIZE, BASIC_H_SIZE,
+ dnode, onode, 0, 0, 0);
+ if (!skb) {
+ pr_warn("%sunable to create tunnel packet\n", link_co_err);
+ return;
+ }
+
+ hdr = buf_msg(skb);
+ msg_set_msgcnt(hdr, 1);
+ msg_set_bearer_id(hdr, l->peer_bearer_id);
+
+ ihdr = (struct tipc_msg *)msg_data(hdr);
+ tipc_msg_init(onode, ihdr, TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
+ BASIC_H_SIZE, dnode);
+ msg_set_errcode(ihdr, TIPC_ERR_NO_PORT);
+ __skb_queue_tail(&tnlq, skb);
+ tipc_link_xmit(l, &tnlq, xmitq);
+}
+
+/* tipc_link_tnl_prepare(): prepare and return a list of tunnel packets
+ * 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)
+{
+ struct sk_buff *skb, *tnlskb;
+ struct tipc_msg *hdr, tnlhdr;
+ struct sk_buff_head *queue = &l->transmq;
+ struct sk_buff_head tmpxq, tnlq;
+ u16 pktlen, pktcnt, seqno = l->snd_nxt;
+
+ if (!tnl)
+ return;
+
+ __skb_queue_head_init(&tnlq);
+ __skb_queue_head_init(&tmpxq);
+
+ /* At least one packet required for safe algorithm => add dummy */
+ skb = tipc_msg_create(TIPC_LOW_IMPORTANCE, TIPC_DIRECT_MSG,
+ BASIC_H_SIZE, 0, l->addr, tipc_own_addr(l->net),
+ 0, 0, TIPC_ERR_NO_PORT);
+ if (!skb) {
+ pr_warn("%sunable to create tunnel packet\n", link_co_err);
+ return;
+ }
+ __skb_queue_tail(&tnlq, skb);
+ tipc_link_xmit(l, &tnlq, &tmpxq);
+ __skb_queue_purge(&tmpxq);
+
+ /* Initialize reusable tunnel packet header */
+ tipc_msg_init(tipc_own_addr(l->net), &tnlhdr, TUNNEL_PROTOCOL,
+ mtyp, INT_H_SIZE, l->addr);
+ pktcnt = skb_queue_len(&l->transmq) + skb_queue_len(&l->backlogq);
+ msg_set_msgcnt(&tnlhdr, pktcnt);
+ msg_set_bearer_id(&tnlhdr, l->peer_bearer_id);
+tnl:
+ /* Wrap each packet into a tunnel packet */
+ skb_queue_walk(queue, skb) {
+ hdr = buf_msg(skb);
+ if (queue == &l->backlogq)
+ msg_set_seqno(hdr, seqno++);
+ pktlen = msg_size(hdr);
+ msg_set_size(&tnlhdr, pktlen + INT_H_SIZE);
+ tnlskb = tipc_buf_acquire(pktlen + INT_H_SIZE, GFP_ATOMIC);
+ if (!tnlskb) {
+ pr_warn("%sunable to send packet\n", link_co_err);
+ return;
+ }
+ skb_copy_to_linear_data(tnlskb, &tnlhdr, INT_H_SIZE);
+ skb_copy_to_linear_data_offset(tnlskb, INT_H_SIZE, hdr, pktlen);
+ __skb_queue_tail(&tnlq, tnlskb);
+ }
+ if (queue != &l->backlogq) {
+ queue = &l->backlogq;
+ goto tnl;
+ }
+
+ tipc_link_xmit(tnl, &tnlq, xmitq);
+
+ if (mtyp == FAILOVER_MSG) {
+ tnl->drop_point = l->rcv_nxt;
+ tnl->failover_reasm_skb = l->reasm_buf;
+ l->reasm_buf = NULL;
+ }
+}
+
+/* tipc_link_validate_msg(): validate message against current link state
+ * Returns true if message should be accepted, otherwise false
+ */
+bool tipc_link_validate_msg(struct tipc_link *l, struct tipc_msg *hdr)
+{
+ u16 curr_session = l->peer_session;
+ u16 session = msg_session(hdr);
+ int mtyp = msg_type(hdr);
+
+ if (msg_user(hdr) != LINK_PROTOCOL)
+ return true;
+
+ switch (mtyp) {
+ case RESET_MSG:
+ if (!l->in_session)
+ return true;
+ /* Accept only RESET with new session number */
+ return more(session, curr_session);
+ case ACTIVATE_MSG:
+ if (!l->in_session)
+ return true;
+ /* Accept only ACTIVATE with new or current session number */
+ return !less(session, curr_session);
+ case STATE_MSG:
+ /* Accept only STATE with current session number */
+ if (!l->in_session)
+ return false;
+ if (session != curr_session)
+ return false;
+ /* Extra sanity check */
+ if (!link_is_up(l) && msg_ack(hdr))
+ return false;
+ if (!(l->peer_caps & TIPC_LINK_PROTO_SEQNO))
+ return true;
+ /* Accept only STATE with new sequence number */
+ return !less(msg_seqno(hdr), l->rcv_nxt_state);
+ default:
+ return false;
+ }
+}
+
+/* tipc_link_proto_rcv(): receive link level protocol message :
+ * Note that network plane id propagates through the network, and may
+ * change at any time. The node with lowest numerical id determines
+ * network plane
+ */
+static int tipc_link_proto_rcv(struct tipc_link *l, struct sk_buff *skb,
+ struct sk_buff_head *xmitq)
+{
+ struct tipc_msg *hdr = buf_msg(skb);
+ u16 rcvgap = 0;
+ u16 ack = msg_ack(hdr);
+ u16 gap = msg_seq_gap(hdr);
+ u16 peers_snd_nxt = msg_next_sent(hdr);
+ u16 peers_tol = msg_link_tolerance(hdr);
+ u16 peers_prio = msg_linkprio(hdr);
+ u16 rcv_nxt = l->rcv_nxt;
+ u32 dlen = msg_data_sz(hdr);
+ int mtyp = msg_type(hdr);
+ bool reply = msg_probe(hdr);
+ void *data;
+ char *if_name;
+ int rc = 0;
+
+ if (dlen > U16_MAX)
+ goto exit;
+
+ if (tipc_link_is_blocked(l) || !xmitq)
+ goto exit;
+
+ if (tipc_own_addr(l->net) > msg_prevnode(hdr))
+ l->net_plane = msg_net_plane(hdr);
+
+ skb_linearize(skb);
+ hdr = buf_msg(skb);
+ data = msg_data(hdr);
+
+ if (!tipc_link_validate_msg(l, hdr))
+ goto exit;
+
+ switch (mtyp) {
+ case RESET_MSG:
+ case ACTIVATE_MSG:
+ /* Complete own link name with peer's interface name */
+ if_name = strrchr(l->name, ':') + 1;
+ if (sizeof(l->name) - (if_name - l->name) <= TIPC_MAX_IF_NAME)
+ break;
+ if (msg_data_sz(hdr) < TIPC_MAX_IF_NAME)
+ break;
+ strncpy(if_name, data, TIPC_MAX_IF_NAME);
+
+ /* Update own tolerance if peer indicates a non-zero value */
+ if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
+ l->tolerance = peers_tol;
+ l->bc_rcvlink->tolerance = peers_tol;
+ }
+ /* Update own priority if peer's priority is higher */
+ if (in_range(peers_prio, l->priority + 1, TIPC_MAX_LINK_PRI))
+ l->priority = peers_prio;
+
+ /* If peer is going down we want full re-establish cycle */
+ if (msg_peer_stopping(hdr)) {
+ rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ break;
+ }
+ /* 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->in_session = true;
+ l->peer_bearer_id = msg_bearer_id(hdr);
+ if (l->mtu > msg_max_pkt(hdr))
+ l->mtu = msg_max_pkt(hdr);
+ break;
+
+ case STATE_MSG:
+ l->rcv_nxt_state = msg_seqno(hdr) + 1;
+
+ /* Update own tolerance if peer indicates a non-zero value */
+ if (in_range(peers_tol, TIPC_MIN_LINK_TOL, TIPC_MAX_LINK_TOL)) {
+ l->tolerance = peers_tol;
+ l->bc_rcvlink->tolerance = peers_tol;
+ }
+ /* Update own prio if peer indicates a different value */
+ if ((peers_prio != l->priority) &&
+ in_range(peers_prio, 1, TIPC_MAX_LINK_PRI)) {
+ l->priority = peers_prio;
+ rc = tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ }
+
+ l->silent_intv_cnt = 0;
+ l->stats.recv_states++;
+ if (msg_probe(hdr))
+ l->stats.recv_probes++;
+
+ if (!link_is_up(l)) {
+ if (l->state == LINK_ESTABLISHING)
+ rc = TIPC_LINK_UP_EVT;
+ break;
+ }
+ tipc_mon_rcv(l->net, data, dlen, l->addr,
+ &l->mon_state, l->bearer_id);
+
+ /* Send NACK if peer has sent pkts we haven't received yet */
+ if (more(peers_snd_nxt, rcv_nxt) && !tipc_link_is_synching(l))
+ rcvgap = peers_snd_nxt - l->rcv_nxt;
+ if (rcvgap || reply)
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
+ rcvgap, 0, 0, xmitq);
+ tipc_link_release_pkts(l, ack);
+
+ /* If NACK, retransmit will now start at right position */
+ if (gap) {
+ rc = tipc_link_retrans(l, l, ack + 1, ack + gap, xmitq);
+ l->stats.recv_nacks++;
+ }
+
+ tipc_link_advance_backlog(l, xmitq);
+ if (unlikely(!skb_queue_empty(&l->wakeupq)))
+ link_prepare_wakeup(l);
+ }
+exit:
+ kfree_skb(skb);
+ return rc;
+}
+
+/* tipc_link_build_bc_proto_msg() - create broadcast protocol message
+ */
+static bool tipc_link_build_bc_proto_msg(struct tipc_link *l, bool bcast,
+ u16 peers_snd_nxt,
+ struct sk_buff_head *xmitq)
+{
+ struct sk_buff *skb;
+ struct tipc_msg *hdr;
+ struct sk_buff *dfrd_skb = skb_peek(&l->deferdq);
+ u16 ack = l->rcv_nxt - 1;
+ u16 gap_to = peers_snd_nxt - 1;
+
+ skb = tipc_msg_create(BCAST_PROTOCOL, STATE_MSG, INT_H_SIZE,
+ 0, l->addr, tipc_own_addr(l->net), 0, 0, 0);
+ if (!skb)
+ return false;
+ hdr = buf_msg(skb);
+ msg_set_last_bcast(hdr, l->bc_sndlink->snd_nxt - 1);
+ msg_set_bcast_ack(hdr, ack);
+ msg_set_bcgap_after(hdr, ack);
+ if (dfrd_skb)
+ gap_to = buf_seqno(dfrd_skb) - 1;
+ msg_set_bcgap_to(hdr, gap_to);
+ msg_set_non_seq(hdr, bcast);
+ __skb_queue_tail(xmitq, skb);
+ return true;
+}
+
+/* tipc_link_build_bc_init_msg() - synchronize broadcast link endpoints.
+ *
+ * Give a newly added peer node the sequence number where it should
+ * start receiving and acking broadcast packets.
+ */
+static void tipc_link_build_bc_init_msg(struct tipc_link *l,
+ struct sk_buff_head *xmitq)
+{
+ struct sk_buff_head list;
+
+ __skb_queue_head_init(&list);
+ if (!tipc_link_build_bc_proto_msg(l->bc_rcvlink, false, 0, &list))
+ return;
+ msg_set_bc_ack_invalid(buf_msg(skb_peek(&list)), true);
+ tipc_link_xmit(l, &list, xmitq);
+}
+
+/* tipc_link_bc_init_rcv - receive initial broadcast synch data from peer
+ */
+void tipc_link_bc_init_rcv(struct tipc_link *l, struct tipc_msg *hdr)
+{
+ int mtyp = msg_type(hdr);
+ u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
+
+ if (link_is_up(l))
+ return;
+
+ if (msg_user(hdr) == BCAST_PROTOCOL) {
+ l->rcv_nxt = peers_snd_nxt;
+ l->state = LINK_ESTABLISHED;
+ return;
+ }
+
+ if (l->peer_caps & TIPC_BCAST_SYNCH)
+ return;
+
+ if (msg_peer_node_is_up(hdr))
+ return;
+
+ /* Compatibility: accept older, less safe initial synch data */
+ if ((mtyp == RESET_MSG) || (mtyp == ACTIVATE_MSG))
+ l->rcv_nxt = peers_snd_nxt;
+}
+
+/* link_bc_retr eval()- check if the indicated range can be retransmitted now
+ * - Adjust permitted range if there is overlap with previous retransmission
+ */
+static bool link_bc_retr_eval(struct tipc_link *l, u16 *from, u16 *to)
+{
+ unsigned long elapsed = jiffies_to_msecs(jiffies - l->prev_retr);
+
+ if (less(*to, *from))
+ return false;
+
+ /* New retransmission request */
+ if ((elapsed > TIPC_BC_RETR_LIMIT) ||
+ less(*to, l->prev_from) || more(*from, l->prev_to)) {
+ l->prev_from = *from;
+ l->prev_to = *to;
+ l->prev_retr = jiffies;
+ return true;
+ }
+
+ /* Inside range of previous retransmit */
+ if (!less(*from, l->prev_from) && !more(*to, l->prev_to))
+ return false;
+
+ /* Fully or partially outside previous range => exclude overlap */
+ if (less(*from, l->prev_from)) {
+ *to = l->prev_from - 1;
+ l->prev_from = *from;
+ }
+ if (more(*to, l->prev_to)) {
+ *from = l->prev_to + 1;
+ l->prev_to = *to;
+ }
+ l->prev_retr = jiffies;
+ return true;
+}
+
+/* tipc_link_bc_sync_rcv - update rcv link according to peer's send state
+ */
+int tipc_link_bc_sync_rcv(struct tipc_link *l, struct tipc_msg *hdr,
+ struct sk_buff_head *xmitq)
+{
+ struct tipc_link *snd_l = l->bc_sndlink;
+ u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
+ u16 from = msg_bcast_ack(hdr) + 1;
+ u16 to = from + msg_bc_gap(hdr) - 1;
+ int rc = 0;
+
+ if (!link_is_up(l))
+ return rc;
+
+ if (!msg_peer_node_is_up(hdr))
+ return rc;
+
+ /* Open when peer ackowledges our bcast init msg (pkt #1) */
+ if (msg_ack(hdr))
+ l->bc_peer_is_up = true;
+
+ if (!l->bc_peer_is_up)
+ return rc;
+
+ l->stats.recv_nacks++;
+
+ /* Ignore if peers_snd_nxt goes beyond receive window */
+ if (more(peers_snd_nxt, l->rcv_nxt + l->window))
+ return rc;
+
+ if (link_bc_retr_eval(snd_l, &from, &to))
+ rc = tipc_link_retrans(snd_l, l, from, to, xmitq);
+
+ l->snd_nxt = peers_snd_nxt;
+ if (link_bc_rcv_gap(l))
+ rc |= TIPC_LINK_SND_STATE;
+
+ /* Return now if sender supports nack via STATE messages */
+ if (l->peer_caps & TIPC_BCAST_STATE_NACK)
+ return rc;
+
+ /* Otherwise, be backwards compatible */
+
+ if (!more(peers_snd_nxt, l->rcv_nxt)) {
+ l->nack_state = BC_NACK_SND_CONDITIONAL;
+ return 0;
+ }
+
+ /* Don't NACK if one was recently sent or peeked */
+ if (l->nack_state == BC_NACK_SND_SUPPRESS) {
+ l->nack_state = BC_NACK_SND_UNCONDITIONAL;
+ return 0;
+ }
+
+ /* Conditionally delay NACK sending until next synch rcv */
+ if (l->nack_state == BC_NACK_SND_CONDITIONAL) {
+ l->nack_state = BC_NACK_SND_UNCONDITIONAL;
+ if ((peers_snd_nxt - l->rcv_nxt) < TIPC_MIN_LINK_WIN)
+ return 0;
+ }
+
+ /* Send NACK now but suppress next one */
+ tipc_link_build_bc_proto_msg(l, true, peers_snd_nxt, xmitq);
+ l->nack_state = BC_NACK_SND_SUPPRESS;
+ return 0;
+}
+
+void tipc_link_bc_ack_rcv(struct tipc_link *l, u16 acked,
+ struct sk_buff_head *xmitq)
+{
+ struct sk_buff *skb, *tmp;
+ struct tipc_link *snd_l = l->bc_sndlink;
+
+ if (!link_is_up(l) || !l->bc_peer_is_up)
+ return;
+
+ if (!more(acked, l->acked))
+ return;
+
+ /* Skip over packets peer has already acked */
+ skb_queue_walk(&snd_l->transmq, skb) {
+ if (more(buf_seqno(skb), l->acked))
+ break;
+ }
+
+ /* Update/release the packets peer is acking now */
+ skb_queue_walk_from_safe(&snd_l->transmq, skb, tmp) {
+ if (more(buf_seqno(skb), acked))
+ break;
+ if (!--TIPC_SKB_CB(skb)->ackers) {
+ __skb_unlink(skb, &snd_l->transmq);
+ kfree_skb(skb);
+ }
+ }
+ l->acked = acked;
+ tipc_link_advance_backlog(snd_l, xmitq);
+ if (unlikely(!skb_queue_empty(&snd_l->wakeupq)))
+ link_prepare_wakeup(snd_l);
+}
+
+/* tipc_link_bc_nack_rcv(): receive broadcast nack message
+ * This function is here for backwards compatibility, since
+ * no BCAST_PROTOCOL/STATE messages occur from TIPC v2.5.
+ */
+int tipc_link_bc_nack_rcv(struct tipc_link *l, struct sk_buff *skb,
+ struct sk_buff_head *xmitq)
+{
+ struct tipc_msg *hdr = buf_msg(skb);
+ u32 dnode = msg_destnode(hdr);
+ int mtyp = msg_type(hdr);
+ u16 acked = msg_bcast_ack(hdr);
+ u16 from = acked + 1;
+ u16 to = msg_bcgap_to(hdr);
+ u16 peers_snd_nxt = to + 1;
+ int rc = 0;
+
+ kfree_skb(skb);
+
+ if (!tipc_link_is_up(l) || !l->bc_peer_is_up)
+ return 0;
+
+ if (mtyp != STATE_MSG)
+ return 0;
+
+ if (dnode == tipc_own_addr(l->net)) {
+ tipc_link_bc_ack_rcv(l, acked, xmitq);
+ rc = tipc_link_retrans(l->bc_sndlink, l, from, to, xmitq);
+ l->stats.recv_nacks++;
+ return rc;
+ }
+
+ /* Msg for other node => suppress own NACK at next sync if applicable */
+ if (more(peers_snd_nxt, l->rcv_nxt) && !less(l->rcv_nxt, from))
+ l->nack_state = BC_NACK_SND_SUPPRESS;
+
+ return 0;
+}
+
+void tipc_link_set_queue_limits(struct tipc_link *l, u32 win)
+{
+ int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
+
+ l->window = win;
+ l->backlog[TIPC_LOW_IMPORTANCE].limit = max_t(u16, 50, win);
+ l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = max_t(u16, 100, win * 2);
+ l->backlog[TIPC_HIGH_IMPORTANCE].limit = max_t(u16, 150, win * 3);
+ l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = max_t(u16, 200, win * 4);
+ l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk;
+}
+
+/**
+ * link_reset_stats - reset link statistics
+ * @l: pointer to link
+ */
+void tipc_link_reset_stats(struct tipc_link *l)
+{
+ memset(&l->stats, 0, sizeof(l->stats));
+}
+
+static void link_print(struct tipc_link *l, const char *str)
+{
+ struct sk_buff *hskb = skb_peek(&l->transmq);
+ u16 head = hskb ? msg_seqno(buf_msg(hskb)) : l->snd_nxt - 1;
+ u16 tail = l->snd_nxt - 1;
+
+ pr_info("%s Link <%s> state %x\n", str, l->name, l->state);
+ pr_info("XMTQ: %u [%u-%u], BKLGQ: %u, SNDNX: %u, RCVNX: %u\n",
+ skb_queue_len(&l->transmq), head, tail,
+ skb_queue_len(&l->backlogq), l->snd_nxt, l->rcv_nxt);
+}
+
+/* Parse and validate nested (link) properties valid for media, bearer and link
+ */
+int tipc_nl_parse_link_prop(struct nlattr *prop, struct nlattr *props[])
+{
+ int err;
+
+ err = nla_parse_nested(props, TIPC_NLA_PROP_MAX, prop,
+ tipc_nl_prop_policy, NULL);
+ if (err)
+ return err;
+
+ if (props[TIPC_NLA_PROP_PRIO]) {
+ u32 prio;
+
+ prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]);
+ if (prio > TIPC_MAX_LINK_PRI)
+ return -EINVAL;
+ }
+
+ if (props[TIPC_NLA_PROP_TOL]) {
+ u32 tol;
+
+ tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]);
+ if ((tol < TIPC_MIN_LINK_TOL) || (tol > TIPC_MAX_LINK_TOL))
+ return -EINVAL;
+ }
+
+ if (props[TIPC_NLA_PROP_WIN]) {
+ u32 win;
+
+ win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
+ if ((win < TIPC_MIN_LINK_WIN) || (win > TIPC_MAX_LINK_WIN))
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static int __tipc_nl_add_stats(struct sk_buff *skb, struct tipc_stats *s)
+{
+ int i;
+ struct nlattr *stats;
+
+ struct nla_map {
+ u32 key;
+ u32 val;
+ };
+
+ struct nla_map map[] = {
+ {TIPC_NLA_STATS_RX_INFO, 0},
+ {TIPC_NLA_STATS_RX_FRAGMENTS, s->recv_fragments},
+ {TIPC_NLA_STATS_RX_FRAGMENTED, s->recv_fragmented},
+ {TIPC_NLA_STATS_RX_BUNDLES, s->recv_bundles},
+ {TIPC_NLA_STATS_RX_BUNDLED, s->recv_bundled},
+ {TIPC_NLA_STATS_TX_INFO, 0},
+ {TIPC_NLA_STATS_TX_FRAGMENTS, s->sent_fragments},
+ {TIPC_NLA_STATS_TX_FRAGMENTED, s->sent_fragmented},
+ {TIPC_NLA_STATS_TX_BUNDLES, s->sent_bundles},
+ {TIPC_NLA_STATS_TX_BUNDLED, s->sent_bundled},
+ {TIPC_NLA_STATS_MSG_PROF_TOT, (s->msg_length_counts) ?
+ s->msg_length_counts : 1},
+ {TIPC_NLA_STATS_MSG_LEN_CNT, s->msg_length_counts},
+ {TIPC_NLA_STATS_MSG_LEN_TOT, s->msg_lengths_total},
+ {TIPC_NLA_STATS_MSG_LEN_P0, s->msg_length_profile[0]},
+ {TIPC_NLA_STATS_MSG_LEN_P1, s->msg_length_profile[1]},
+ {TIPC_NLA_STATS_MSG_LEN_P2, s->msg_length_profile[2]},
+ {TIPC_NLA_STATS_MSG_LEN_P3, s->msg_length_profile[3]},
+ {TIPC_NLA_STATS_MSG_LEN_P4, s->msg_length_profile[4]},
+ {TIPC_NLA_STATS_MSG_LEN_P5, s->msg_length_profile[5]},
+ {TIPC_NLA_STATS_MSG_LEN_P6, s->msg_length_profile[6]},
+ {TIPC_NLA_STATS_RX_STATES, s->recv_states},
+ {TIPC_NLA_STATS_RX_PROBES, s->recv_probes},
+ {TIPC_NLA_STATS_RX_NACKS, s->recv_nacks},
+ {TIPC_NLA_STATS_RX_DEFERRED, s->deferred_recv},
+ {TIPC_NLA_STATS_TX_STATES, s->sent_states},
+ {TIPC_NLA_STATS_TX_PROBES, s->sent_probes},
+ {TIPC_NLA_STATS_TX_NACKS, s->sent_nacks},
+ {TIPC_NLA_STATS_TX_ACKS, s->sent_acks},
+ {TIPC_NLA_STATS_RETRANSMITTED, s->retransmitted},
+ {TIPC_NLA_STATS_DUPLICATES, s->duplicates},
+ {TIPC_NLA_STATS_LINK_CONGS, s->link_congs},
+ {TIPC_NLA_STATS_MAX_QUEUE, s->max_queue_sz},
+ {TIPC_NLA_STATS_AVG_QUEUE, s->queue_sz_counts ?
+ (s->accu_queue_sz / s->queue_sz_counts) : 0}
+ };
+
+ stats = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
+ if (!stats)
+ return -EMSGSIZE;
+
+ for (i = 0; i < ARRAY_SIZE(map); i++)
+ if (nla_put_u32(skb, map[i].key, map[i].val))
+ goto msg_full;
+
+ nla_nest_end(skb, stats);
+
+ return 0;
+msg_full:
+ nla_nest_cancel(skb, stats);
+
+ return -EMSGSIZE;
+}
+
+/* Caller should hold appropriate locks to protect the link */
+int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg,
+ struct tipc_link *link, int nlflags)
+{
+ u32 self = tipc_own_addr(net);
+ struct nlattr *attrs;
+ struct nlattr *prop;
+ void *hdr;
+ int err;
+
+ hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
+ nlflags, TIPC_NL_LINK_GET);
+ if (!hdr)
+ return -EMSGSIZE;
+
+ attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
+ if (!attrs)
+ goto msg_full;
+
+ if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, link->name))
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_LINK_DEST, tipc_cluster_mask(self)))
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_LINK_MTU, link->mtu))
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, link->stats.recv_pkts))
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->stats.sent_pkts))
+ goto attr_msg_full;
+
+ if (tipc_link_is_up(link))
+ if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
+ goto attr_msg_full;
+ if (link->active)
+ if (nla_put_flag(msg->skb, TIPC_NLA_LINK_ACTIVE))
+ goto attr_msg_full;
+
+ prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
+ if (!prop)
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
+ goto prop_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_TOL, link->tolerance))
+ goto prop_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN,
+ link->window))
+ goto prop_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_PRIO, link->priority))
+ goto prop_msg_full;
+ nla_nest_end(msg->skb, prop);
+
+ err = __tipc_nl_add_stats(msg->skb, &link->stats);
+ if (err)
+ goto attr_msg_full;
+
+ nla_nest_end(msg->skb, attrs);
+ genlmsg_end(msg->skb, hdr);
+
+ return 0;
+
+prop_msg_full:
+ nla_nest_cancel(msg->skb, prop);
+attr_msg_full:
+ nla_nest_cancel(msg->skb, attrs);
+msg_full:
+ genlmsg_cancel(msg->skb, hdr);
+
+ return -EMSGSIZE;
+}
+
+static int __tipc_nl_add_bc_link_stat(struct sk_buff *skb,
+ struct tipc_stats *stats)
+{
+ int i;
+ struct nlattr *nest;
+
+ struct nla_map {
+ __u32 key;
+ __u32 val;
+ };
+
+ struct nla_map map[] = {
+ {TIPC_NLA_STATS_RX_INFO, stats->recv_pkts},
+ {TIPC_NLA_STATS_RX_FRAGMENTS, stats->recv_fragments},
+ {TIPC_NLA_STATS_RX_FRAGMENTED, stats->recv_fragmented},
+ {TIPC_NLA_STATS_RX_BUNDLES, stats->recv_bundles},
+ {TIPC_NLA_STATS_RX_BUNDLED, stats->recv_bundled},
+ {TIPC_NLA_STATS_TX_INFO, stats->sent_pkts},
+ {TIPC_NLA_STATS_TX_FRAGMENTS, stats->sent_fragments},
+ {TIPC_NLA_STATS_TX_FRAGMENTED, stats->sent_fragmented},
+ {TIPC_NLA_STATS_TX_BUNDLES, stats->sent_bundles},
+ {TIPC_NLA_STATS_TX_BUNDLED, stats->sent_bundled},
+ {TIPC_NLA_STATS_RX_NACKS, stats->recv_nacks},
+ {TIPC_NLA_STATS_RX_DEFERRED, stats->deferred_recv},
+ {TIPC_NLA_STATS_TX_NACKS, stats->sent_nacks},
+ {TIPC_NLA_STATS_TX_ACKS, stats->sent_acks},
+ {TIPC_NLA_STATS_RETRANSMITTED, stats->retransmitted},
+ {TIPC_NLA_STATS_DUPLICATES, stats->duplicates},
+ {TIPC_NLA_STATS_LINK_CONGS, stats->link_congs},
+ {TIPC_NLA_STATS_MAX_QUEUE, stats->max_queue_sz},
+ {TIPC_NLA_STATS_AVG_QUEUE, stats->queue_sz_counts ?
+ (stats->accu_queue_sz / stats->queue_sz_counts) : 0}
+ };
+
+ nest = nla_nest_start(skb, TIPC_NLA_LINK_STATS);
+ if (!nest)
+ return -EMSGSIZE;
+
+ for (i = 0; i < ARRAY_SIZE(map); i++)
+ if (nla_put_u32(skb, map[i].key, map[i].val))
+ goto msg_full;
+
+ nla_nest_end(skb, nest);
+
+ return 0;
+msg_full:
+ nla_nest_cancel(skb, nest);
+
+ return -EMSGSIZE;
+}
+
+int tipc_nl_add_bc_link(struct net *net, struct tipc_nl_msg *msg)
+{
+ int err;
+ void *hdr;
+ struct nlattr *attrs;
+ struct nlattr *prop;
+ struct tipc_net *tn = net_generic(net, tipc_net_id);
+ struct tipc_link *bcl = tn->bcl;
+
+ if (!bcl)
+ return 0;
+
+ tipc_bcast_lock(net);
+
+ hdr = genlmsg_put(msg->skb, msg->portid, msg->seq, &tipc_genl_family,
+ NLM_F_MULTI, TIPC_NL_LINK_GET);
+ if (!hdr) {
+ tipc_bcast_unlock(net);
+ return -EMSGSIZE;
+ }
+
+ attrs = nla_nest_start(msg->skb, TIPC_NLA_LINK);
+ if (!attrs)
+ goto msg_full;
+
+ /* The broadcast link is always up */
+ if (nla_put_flag(msg->skb, TIPC_NLA_LINK_UP))
+ goto attr_msg_full;
+
+ if (nla_put_flag(msg->skb, TIPC_NLA_LINK_BROADCAST))
+ goto attr_msg_full;
+ if (nla_put_string(msg->skb, TIPC_NLA_LINK_NAME, bcl->name))
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_LINK_RX, 0))
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, 0))
+ goto attr_msg_full;
+
+ prop = nla_nest_start(msg->skb, TIPC_NLA_LINK_PROP);
+ if (!prop)
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->window))
+ goto prop_msg_full;
+ nla_nest_end(msg->skb, prop);
+
+ err = __tipc_nl_add_bc_link_stat(msg->skb, &bcl->stats);
+ if (err)
+ goto attr_msg_full;
+
+ tipc_bcast_unlock(net);
+ nla_nest_end(msg->skb, attrs);
+ genlmsg_end(msg->skb, hdr);
+
+ return 0;
+
+prop_msg_full:
+ nla_nest_cancel(msg->skb, prop);
+attr_msg_full:
+ nla_nest_cancel(msg->skb, attrs);
+msg_full:
+ tipc_bcast_unlock(net);
+ genlmsg_cancel(msg->skb, hdr);
+
+ return -EMSGSIZE;
+}
+
+void tipc_link_set_tolerance(struct tipc_link *l, u32 tol,
+ struct sk_buff_head *xmitq)
+{
+ l->tolerance = tol;
+ if (l->bc_rcvlink)
+ l->bc_rcvlink->tolerance = tol;
+ if (link_is_up(l))
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, tol, 0, xmitq);
+}
+
+void tipc_link_set_prio(struct tipc_link *l, u32 prio,
+ struct sk_buff_head *xmitq)
+{
+ l->priority = prio;
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, prio, xmitq);
+}
+
+void tipc_link_set_abort_limit(struct tipc_link *l, u32 limit)
+{
+ l->abort_limit = limit;
+}