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diff --git a/net/tipc/link.c b/net/tipc/link.c
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+++ b/net/tipc/link.c
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+/*
+ * 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 "trace.h"
+#include "crypto.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
+ * @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;
+ struct sk_buff_head failover_deferdq;
+
+ /* 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;
+
+ /* 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;
+ u16 window;
+ u16 min_win;
+ u16 ssthresh;
+ u16 max_win;
+ u16 cong_acks;
+ u16 checkpoint;
+
+ /* Fragmentation/reassembly */
+ struct sk_buff *reasm_buf;
+ struct sk_buff *reasm_tnlmsg;
+
+ /* Broadcast */
+ u16 ackers;
+ u16 acked;
+ u16 last_gap;
+ struct tipc_gap_ack_blks *last_ga;
+ struct tipc_link *bc_rcvlink;
+ struct tipc_link *bc_sndlink;
+ 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_LIM (jiffies + msecs_to_jiffies(10))
+#define TIPC_UC_RETR_TIME (jiffies + msecs_to_jiffies(1))
+
+/* 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 u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
+ struct tipc_link *l, u8 start_index);
+static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr);
+static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
+ u16 acked, u16 gap,
+ struct tipc_gap_ack_blks *ga,
+ struct sk_buff_head *xmitq,
+ bool *retransmitted, int *rc);
+static void tipc_link_update_cwin(struct tipc_link *l, int released,
+ bool retransmitted);
+/*
+ * 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_min_win(struct tipc_link *l)
+{
+ return l->min_win;
+}
+
+int tipc_link_max_win(struct tipc_link *l)
+{
+ return l->max_win;
+}
+
+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;
+}
+
+struct net *tipc_link_net(struct tipc_link *l)
+{
+ return l->net;
+}
+
+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, 0, NULL, xmitq, NULL);
+ trace_tipc_link_reset(rcv_l, TIPC_DUMP_ALL, "bclink removed!");
+ tipc_link_reset(rcv_l);
+ rcv_l->state = LINK_RESET;
+ if (!snd_l->ackers) {
+ trace_tipc_link_reset(snd_l, TIPC_DUMP_ALL, "zero 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;
+}
+
+int tipc_link_mss(struct tipc_link *l)
+{
+#ifdef CONFIG_TIPC_CRYPTO
+ return l->mtu - INT_H_SIZE - EMSG_OVERHEAD;
+#else
+ return l->mtu - INT_H_SIZE;
+#endif
+}
+
+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
+ * @net: pointer to associated network namespace
+ * @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
+ * @min_win: minimal send window to be used by link
+ * @max_win: maximal 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,
+ u32 min_win, u32 max_win, 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, min_win, max_win);
+ 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->failover_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
+ * @net: pointer to associated network namespace
+ * @mtu: mtu to be used initially if no peers
+ * @min_win: minimal send window to be used by link
+ * @max_win: maximal send window to be used by link
+ * @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, u8 *peer_id,
+ int mtu, u32 min_win, u32 max_win, 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, min_win,
+ max_win, 0, ownnode, peer, NULL, peer_caps,
+ bc_sndlink, NULL, inputq, namedq, link))
+ return false;
+
+ l = *link;
+ if (peer_id) {
+ char peer_str[NODE_ID_STR_LEN] = {0,};
+
+ tipc_nodeid2string(peer_str, peer_id);
+ if (strlen(peer_str) > 16)
+ sprintf(peer_str, "%x", peer);
+ /* Broadcast receiver link name: "broadcast-link:<peer>" */
+ snprintf(l->name, sizeof(l->name), "%s:%s", tipc_bclink_name,
+ peer_str);
+ } else {
+ strcpy(l->name, tipc_bclink_name);
+ }
+ trace_tipc_link_reset(l, TIPC_DUMP_ALL, "bclink created!");
+ 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_toggle_rcast(net, false);
+
+ 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;
+ int old_state = l->state;
+
+ 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);
+ }
+ trace_tipc_link_fsm(l->name, old_state, l->state, evt);
+ return rc;
+illegal_evt:
+ pr_err("Illegal FSM event %x in state %x on link %s\n",
+ evt, l->state, l->name);
+ trace_tipc_link_fsm(l->name, old_state, l->state, evt);
+ 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_inner_hdr(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_too_silent - check if link is "too silent"
+ * @l: tipc link to be checked
+ *
+ * Returns true if the link 'silent_intv_cnt' is about to reach the
+ * 'abort_limit' value, otherwise false
+ */
+bool tipc_link_too_silent(struct tipc_link *l)
+{
+ return (l->silent_intv_cnt + 2 > l->abort_limit);
+}
+
+/* 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;
+
+ trace_tipc_link_timeout(l, TIPC_DUMP_NONE, " ");
+ trace_tipc_link_too_silent(l, TIPC_DUMP_ALL, " ");
+ 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);
+ probe = mstate->probing;
+ probe |= l->silent_intv_cnt;
+ if (probe || mstate->monitoring)
+ l->silent_intv_cnt++;
+ probe |= !skb_queue_empty(&l->deferdq);
+ if (l->snd_nxt == l->checkpoint) {
+ tipc_link_update_cwin(l, 0, 0);
+ probe = true;
+ }
+ l->checkpoint = l->snd_nxt;
+ 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++;
+ trace_tipc_link_conges(l, TIPC_DUMP_ALL, "wakeup scheduled!");
+ 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);
+
+}
+
+/**
+ * tipc_link_set_skb_retransmit_time - set the time at which retransmission of
+ * the given skb should be next attempted
+ * @skb: skb to set a future retransmission time for
+ * @l: link the skb will be transmitted on
+ */
+static void tipc_link_set_skb_retransmit_time(struct sk_buff *skb,
+ struct tipc_link *l)
+{
+ if (link_is_bc_sndlink(l))
+ TIPC_SKB_CB(skb)->nxt_retr = TIPC_BC_RETR_LIM;
+ else
+ TIPC_SKB_CB(skb)->nxt_retr = TIPC_UC_RETR_TIME;
+}
+
+void tipc_link_reset(struct tipc_link *l)
+{
+ struct sk_buff_head list;
+ u32 imp;
+
+ __skb_queue_head_init(&list);
+
+ l->in_session = false;
+ /* Force re-synch of peer session number before establishing */
+ l->peer_session--;
+ 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);
+ __skb_queue_purge(&l->failover_deferdq);
+ 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->reasm_tnlmsg);
+ kfree_skb(l->failover_reasm_skb);
+ l->reasm_buf = NULL;
+ l->reasm_tnlmsg = 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->last_gap = 0;
+ kfree(l->last_ga);
+ l->last_ga = NULL;
+ l->silent_intv_cnt = 0;
+ l->rst_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
+ * @l: 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)
+{
+ struct sk_buff_head *backlogq = &l->backlogq;
+ struct sk_buff_head *transmq = &l->transmq;
+ struct sk_buff *skb, *_skb;
+ u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
+ u16 ack = l->rcv_nxt - 1;
+ u16 seqno = l->snd_nxt;
+ int pkt_cnt = skb_queue_len(list);
+ unsigned int mss = tipc_link_mss(l);
+ unsigned int cwin = l->window;
+ unsigned int mtu = l->mtu;
+ struct tipc_msg *hdr;
+ bool new_bundle;
+ int rc = 0;
+ int imp;
+
+ if (pkt_cnt <= 0)
+ return 0;
+
+ hdr = buf_msg(skb_peek(list));
+ if (unlikely(msg_size(hdr) > mtu)) {
+ pr_warn("Too large msg, purging xmit list %d %d %d %d %d!\n",
+ skb_queue_len(list), msg_user(hdr),
+ msg_type(hdr), 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 = __skb_dequeue(list))) {
+ if (likely(skb_queue_len(transmq) < cwin)) {
+ hdr = buf_msg(skb);
+ msg_set_seqno(hdr, seqno);
+ msg_set_ack(hdr, ack);
+ msg_set_bcast_ack(hdr, bc_ack);
+ _skb = skb_clone(skb, GFP_ATOMIC);
+ if (!_skb) {
+ kfree_skb(skb);
+ __skb_queue_purge(list);
+ return -ENOBUFS;
+ }
+ __skb_queue_tail(transmq, skb);
+ tipc_link_set_skb_retransmit_time(skb, l);
+ __skb_queue_tail(xmitq, _skb);
+ TIPC_SKB_CB(skb)->ackers = l->ackers;
+ l->rcv_unacked = 0;
+ l->stats.sent_pkts++;
+ seqno++;
+ continue;
+ }
+ if (tipc_msg_try_bundle(l->backlog[imp].target_bskb, &skb,
+ mss, l->addr, &new_bundle)) {
+ if (skb) {
+ /* Keep a ref. to the skb for next try */
+ l->backlog[imp].target_bskb = skb;
+ l->backlog[imp].len++;
+ __skb_queue_tail(backlogq, skb);
+ } else {
+ if (new_bundle) {
+ l->stats.sent_bundles++;
+ l->stats.sent_bundled++;
+ }
+ l->stats.sent_bundled++;
+ }
+ continue;
+ }
+ l->backlog[imp].target_bskb = NULL;
+ l->backlog[imp].len += (1 + skb_queue_len(list));
+ __skb_queue_tail(backlogq, skb);
+ skb_queue_splice_tail_init(list, backlogq);
+ }
+ l->snd_nxt = seqno;
+ return rc;
+}
+
+static void tipc_link_update_cwin(struct tipc_link *l, int released,
+ bool retransmitted)
+{
+ int bklog_len = skb_queue_len(&l->backlogq);
+ struct sk_buff_head *txq = &l->transmq;
+ int txq_len = skb_queue_len(txq);
+ u16 cwin = l->window;
+
+ /* Enter fast recovery */
+ if (unlikely(retransmitted)) {
+ l->ssthresh = max_t(u16, l->window / 2, 300);
+ l->window = min_t(u16, l->ssthresh, l->window);
+ return;
+ }
+ /* Enter slow start */
+ if (unlikely(!released)) {
+ l->ssthresh = max_t(u16, l->window / 2, 300);
+ l->window = l->min_win;
+ return;
+ }
+ /* Don't increase window if no pressure on the transmit queue */
+ if (txq_len + bklog_len < cwin)
+ return;
+
+ /* Don't increase window if there are holes the transmit queue */
+ if (txq_len && l->snd_nxt - buf_seqno(skb_peek(txq)) != txq_len)
+ return;
+
+ l->cong_acks += released;
+
+ /* Slow start */
+ if (cwin <= l->ssthresh) {
+ l->window = min_t(u16, cwin + released, l->max_win);
+ return;
+ }
+ /* Congestion avoidance */
+ if (l->cong_acks < cwin)
+ return;
+ l->window = min_t(u16, ++cwin, l->max_win);
+ l->cong_acks = 0;
+}
+
+static void tipc_link_advance_backlog(struct tipc_link *l,
+ struct sk_buff_head *xmitq)
+{
+ u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
+ struct sk_buff_head *txq = &l->transmq;
+ struct sk_buff *skb, *_skb;
+ u16 ack = l->rcv_nxt - 1;
+ u16 seqno = l->snd_nxt;
+ struct tipc_msg *hdr;
+ u16 cwin = l->window;
+ u32 imp;
+
+ while (skb_queue_len(txq) < cwin) {
+ 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);
+ tipc_link_set_skb_retransmit_time(skb, l);
+
+ __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;
+}
+
+/**
+ * link_retransmit_failure() - Detect repeated retransmit failures
+ * @l: tipc link sender
+ * @r: tipc link receiver (= l in case of unicast)
+ * @rc: returned code
+ *
+ * Return: true if the repeated retransmit failures happens, otherwise
+ * false
+ */
+static bool link_retransmit_failure(struct tipc_link *l, struct tipc_link *r,
+ int *rc)
+{
+ struct sk_buff *skb = skb_peek(&l->transmq);
+ struct tipc_msg *hdr;
+
+ if (!skb)
+ return false;
+
+ if (!TIPC_SKB_CB(skb)->retr_cnt)
+ return false;
+
+ if (!time_after(jiffies, TIPC_SKB_CB(skb)->retr_stamp +
+ msecs_to_jiffies(r->tolerance * 10)))
+ return false;
+
+ hdr = buf_msg(skb);
+ if (link_is_bc_sndlink(l) && !less(r->acked, msg_seqno(hdr)))
+ return false;
+
+ 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, dest: %x\n",
+ msg_seqno(hdr), msg_prevnode(hdr), msg_destnode(hdr));
+ pr_info("retr_stamp %d, retr_cnt %d\n",
+ jiffies_to_msecs(TIPC_SKB_CB(skb)->retr_stamp),
+ TIPC_SKB_CB(skb)->retr_cnt);
+
+ trace_tipc_list_dump(&l->transmq, true, "retrans failure!");
+ trace_tipc_link_dump(l, TIPC_DUMP_NONE, "retrans failure!");
+ trace_tipc_link_dump(r, TIPC_DUMP_NONE, "retrans failure!");
+
+ if (link_is_bc_sndlink(l)) {
+ r->state = LINK_RESET;
+ *rc |= TIPC_LINK_DOWN_EVT;
+ } else {
+ *rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ }
+
+ return true;
+}
+
+/* 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;
+ }
+ fallthrough;
+ 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;
+#ifdef CONFIG_TIPC_CRYPTO
+ case MSG_CRYPTO:
+ if (TIPC_SKB_CB(skb)->decrypted) {
+ tipc_crypto_msg_rcv(l->net, skb);
+ return true;
+ }
+ fallthrough;
+#endif
+ 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 sk_buff **reasm_skb)
+{
+ struct tipc_msg *hdr = buf_msg(skb);
+ struct sk_buff *iskb;
+ struct sk_buff_head tmpq;
+ int usr = msg_user(hdr);
+ int pos = 0;
+
+ 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);
+ }
+
+ kfree_skb(skb);
+ return 0;
+}
+
+/* tipc_link_tnl_rcv() - receive TUNNEL_PROTOCOL message, drop or process the
+ * inner message along with the ones in the old link's
+ * deferdq
+ * @l: tunnel link
+ * @skb: TUNNEL_PROTOCOL message
+ * @inputq: queue to put messages ready for delivery
+ */
+static int tipc_link_tnl_rcv(struct tipc_link *l, struct sk_buff *skb,
+ struct sk_buff_head *inputq)
+{
+ struct sk_buff **reasm_skb = &l->failover_reasm_skb;
+ struct sk_buff **reasm_tnlmsg = &l->reasm_tnlmsg;
+ struct sk_buff_head *fdefq = &l->failover_deferdq;
+ struct tipc_msg *hdr = buf_msg(skb);
+ struct sk_buff *iskb;
+ int ipos = 0;
+ int rc = 0;
+ u16 seqno;
+
+ if (msg_type(hdr) == SYNCH_MSG) {
+ kfree_skb(skb);
+ return 0;
+ }
+
+ /* Not a fragment? */
+ if (likely(!msg_nof_fragms(hdr))) {
+ if (unlikely(!tipc_msg_extract(skb, &iskb, &ipos))) {
+ pr_warn_ratelimited("Unable to extract msg, defq: %d\n",
+ skb_queue_len(fdefq));
+ return 0;
+ }
+ kfree_skb(skb);
+ } else {
+ /* Set fragment type for buf_append */
+ if (msg_fragm_no(hdr) == 1)
+ msg_set_type(hdr, FIRST_FRAGMENT);
+ else if (msg_fragm_no(hdr) < msg_nof_fragms(hdr))
+ msg_set_type(hdr, FRAGMENT);
+ else
+ msg_set_type(hdr, LAST_FRAGMENT);
+
+ if (!tipc_buf_append(reasm_tnlmsg, &skb)) {
+ /* Successful but non-complete reassembly? */
+ if (*reasm_tnlmsg || link_is_bc_rcvlink(l))
+ return 0;
+ pr_warn_ratelimited("Unable to reassemble tunnel msg\n");
+ return tipc_link_fsm_evt(l, LINK_FAILURE_EVT);
+ }
+ iskb = skb;
+ }
+
+ do {
+ seqno = buf_seqno(iskb);
+ if (unlikely(less(seqno, l->drop_point))) {
+ kfree_skb(iskb);
+ continue;
+ }
+ if (unlikely(seqno != l->drop_point)) {
+ __tipc_skb_queue_sorted(fdefq, seqno, iskb);
+ continue;
+ }
+
+ l->drop_point++;
+ if (!tipc_data_input(l, iskb, inputq))
+ rc |= tipc_link_input(l, iskb, inputq, reasm_skb);
+ if (unlikely(rc))
+ break;
+ } while ((iskb = __tipc_skb_dequeue(fdefq, l->drop_point)));
+
+ return rc;
+}
+
+/**
+ * tipc_get_gap_ack_blks - get Gap ACK blocks from PROTOCOL/STATE_MSG
+ * @ga: returned pointer to the Gap ACK blocks if any
+ * @l: the tipc link
+ * @hdr: the PROTOCOL/STATE_MSG header
+ * @uc: desired Gap ACK blocks type, i.e. unicast (= 1) or broadcast (= 0)
+ *
+ * Return: the total Gap ACK blocks size
+ */
+u16 tipc_get_gap_ack_blks(struct tipc_gap_ack_blks **ga, struct tipc_link *l,
+ struct tipc_msg *hdr, bool uc)
+{
+ struct tipc_gap_ack_blks *p;
+ u16 sz = 0;
+
+ /* Does peer support the Gap ACK blocks feature? */
+ if (l->peer_caps & TIPC_GAP_ACK_BLOCK) {
+ p = (struct tipc_gap_ack_blks *)msg_data(hdr);
+ sz = ntohs(p->len);
+ /* Sanity check */
+ if (sz == struct_size(p, gacks, size_add(p->ugack_cnt, p->bgack_cnt))) {
+ /* Good, check if the desired type exists */
+ if ((uc && p->ugack_cnt) || (!uc && p->bgack_cnt))
+ goto ok;
+ /* Backward compatible: peer might not support bc, but uc? */
+ } else if (uc && sz == struct_size(p, gacks, p->ugack_cnt)) {
+ if (p->ugack_cnt) {
+ p->bgack_cnt = 0;
+ goto ok;
+ }
+ }
+ }
+ /* Other cases: ignore! */
+ p = NULL;
+
+ok:
+ *ga = p;
+ return sz;
+}
+
+static u8 __tipc_build_gap_ack_blks(struct tipc_gap_ack_blks *ga,
+ struct tipc_link *l, u8 start_index)
+{
+ struct tipc_gap_ack *gacks = &ga->gacks[start_index];
+ struct sk_buff *skb = skb_peek(&l->deferdq);
+ u16 expect, seqno = 0;
+ u8 n = 0;
+
+ if (!skb)
+ return 0;
+
+ expect = buf_seqno(skb);
+ skb_queue_walk(&l->deferdq, skb) {
+ seqno = buf_seqno(skb);
+ if (unlikely(more(seqno, expect))) {
+ gacks[n].ack = htons(expect - 1);
+ gacks[n].gap = htons(seqno - expect);
+ if (++n >= MAX_GAP_ACK_BLKS / 2) {
+ pr_info_ratelimited("Gacks on %s: %d, ql: %d!\n",
+ l->name, n,
+ skb_queue_len(&l->deferdq));
+ return n;
+ }
+ } else if (unlikely(less(seqno, expect))) {
+ pr_warn("Unexpected skb in deferdq!\n");
+ continue;
+ }
+ expect = seqno + 1;
+ }
+
+ /* last block */
+ gacks[n].ack = htons(seqno);
+ gacks[n].gap = 0;
+ n++;
+ return n;
+}
+
+/* tipc_build_gap_ack_blks - build Gap ACK blocks
+ * @l: tipc unicast link
+ * @hdr: the tipc message buffer to store the Gap ACK blocks after built
+ *
+ * The function builds Gap ACK blocks for both the unicast & broadcast receiver
+ * links of a certain peer, the buffer after built has the network data format
+ * as found at the struct tipc_gap_ack_blks definition.
+ *
+ * returns the actual allocated memory size
+ */
+static u16 tipc_build_gap_ack_blks(struct tipc_link *l, struct tipc_msg *hdr)
+{
+ struct tipc_link *bcl = l->bc_rcvlink;
+ struct tipc_gap_ack_blks *ga;
+ u16 len;
+
+ ga = (struct tipc_gap_ack_blks *)msg_data(hdr);
+
+ /* Start with broadcast link first */
+ tipc_bcast_lock(bcl->net);
+ msg_set_bcast_ack(hdr, bcl->rcv_nxt - 1);
+ msg_set_bc_gap(hdr, link_bc_rcv_gap(bcl));
+ ga->bgack_cnt = __tipc_build_gap_ack_blks(ga, bcl, 0);
+ tipc_bcast_unlock(bcl->net);
+
+ /* Now for unicast link, but an explicit NACK only (???) */
+ ga->ugack_cnt = (msg_seq_gap(hdr)) ?
+ __tipc_build_gap_ack_blks(ga, l, ga->bgack_cnt) : 0;
+
+ /* Total len */
+ len = struct_size(ga, gacks, size_add(ga->bgack_cnt, ga->ugack_cnt));
+ ga->len = htons(len);
+ return len;
+}
+
+/* tipc_link_advance_transmq - advance TIPC link transmq queue by releasing
+ * acked packets, also doing retransmissions if
+ * gaps found
+ * @l: tipc link with transmq queue to be advanced
+ * @r: tipc link "receiver" i.e. in case of broadcast (= "l" if unicast)
+ * @acked: seqno of last packet acked by peer without any gaps before
+ * @gap: # of gap packets
+ * @ga: buffer pointer to Gap ACK blocks from peer
+ * @xmitq: queue for accumulating the retransmitted packets if any
+ * @retransmitted: returned boolean value if a retransmission is really issued
+ * @rc: returned code e.g. TIPC_LINK_DOWN_EVT if a repeated retransmit failures
+ * happens (- unlikely case)
+ *
+ * Return: the number of packets released from the link transmq
+ */
+static int tipc_link_advance_transmq(struct tipc_link *l, struct tipc_link *r,
+ u16 acked, u16 gap,
+ struct tipc_gap_ack_blks *ga,
+ struct sk_buff_head *xmitq,
+ bool *retransmitted, int *rc)
+{
+ struct tipc_gap_ack_blks *last_ga = r->last_ga, *this_ga = NULL;
+ struct tipc_gap_ack *gacks = NULL;
+ struct sk_buff *skb, *_skb, *tmp;
+ struct tipc_msg *hdr;
+ u32 qlen = skb_queue_len(&l->transmq);
+ u16 nacked = acked, ngap = gap, gack_cnt = 0;
+ u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1;
+ u16 ack = l->rcv_nxt - 1;
+ u16 seqno, n = 0;
+ u16 end = r->acked, start = end, offset = r->last_gap;
+ u16 si = (last_ga) ? last_ga->start_index : 0;
+ bool is_uc = !link_is_bc_sndlink(l);
+ bool bc_has_acked = false;
+
+ trace_tipc_link_retrans(r, acked + 1, acked + gap, &l->transmq);
+
+ /* Determine Gap ACK blocks if any for the particular link */
+ if (ga && is_uc) {
+ /* Get the Gap ACKs, uc part */
+ gack_cnt = ga->ugack_cnt;
+ gacks = &ga->gacks[ga->bgack_cnt];
+ } else if (ga) {
+ /* Copy the Gap ACKs, bc part, for later renewal if needed */
+ this_ga = kmemdup(ga, struct_size(ga, gacks, ga->bgack_cnt),
+ GFP_ATOMIC);
+ if (likely(this_ga)) {
+ this_ga->start_index = 0;
+ /* Start with the bc Gap ACKs */
+ gack_cnt = this_ga->bgack_cnt;
+ gacks = &this_ga->gacks[0];
+ } else {
+ /* Hmm, we can get in trouble..., simply ignore it */
+ pr_warn_ratelimited("Ignoring bc Gap ACKs, no memory\n");
+ }
+ }
+
+ /* Advance the link transmq */
+ skb_queue_walk_safe(&l->transmq, skb, tmp) {
+ seqno = buf_seqno(skb);
+
+next_gap_ack:
+ if (less_eq(seqno, nacked)) {
+ if (is_uc)
+ goto release;
+ /* Skip packets peer has already acked */
+ if (!more(seqno, r->acked))
+ continue;
+ /* Get the next of last Gap ACK blocks */
+ while (more(seqno, end)) {
+ if (!last_ga || si >= last_ga->bgack_cnt)
+ break;
+ start = end + offset + 1;
+ end = ntohs(last_ga->gacks[si].ack);
+ offset = ntohs(last_ga->gacks[si].gap);
+ si++;
+ WARN_ONCE(more(start, end) ||
+ (!offset &&
+ si < last_ga->bgack_cnt) ||
+ si > MAX_GAP_ACK_BLKS,
+ "Corrupted Gap ACK: %d %d %d %d %d\n",
+ start, end, offset, si,
+ last_ga->bgack_cnt);
+ }
+ /* Check against the last Gap ACK block */
+ if (in_range(seqno, start, end))
+ continue;
+ /* Update/release the packet peer is acking */
+ bc_has_acked = true;
+ if (--TIPC_SKB_CB(skb)->ackers)
+ continue;
+release:
+ /* release skb */
+ __skb_unlink(skb, &l->transmq);
+ kfree_skb(skb);
+ } else if (less_eq(seqno, nacked + ngap)) {
+ /* First gap: check if repeated retrans failures? */
+ if (unlikely(seqno == acked + 1 &&
+ link_retransmit_failure(l, r, rc))) {
+ /* Ignore this bc Gap ACKs if any */
+ kfree(this_ga);
+ this_ga = NULL;
+ break;
+ }
+ /* retransmit skb if unrestricted*/
+ if (time_before(jiffies, TIPC_SKB_CB(skb)->nxt_retr))
+ continue;
+ tipc_link_set_skb_retransmit_time(skb, l);
+ _skb = pskb_copy(skb, GFP_ATOMIC);
+ if (!_skb)
+ continue;
+ 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++;
+ if (!is_uc)
+ r->stats.retransmitted++;
+ *retransmitted = true;
+ /* Increase actual retrans counter & mark first time */
+ if (!TIPC_SKB_CB(skb)->retr_cnt++)
+ TIPC_SKB_CB(skb)->retr_stamp = jiffies;
+ } else {
+ /* retry with Gap ACK blocks if any */
+ if (n >= gack_cnt)
+ break;
+ nacked = ntohs(gacks[n].ack);
+ ngap = ntohs(gacks[n].gap);
+ n++;
+ goto next_gap_ack;
+ }
+ }
+
+ /* Renew last Gap ACK blocks for bc if needed */
+ if (bc_has_acked) {
+ if (this_ga) {
+ kfree(last_ga);
+ r->last_ga = this_ga;
+ r->last_gap = gap;
+ } else if (last_ga) {
+ if (less(acked, start)) {
+ si--;
+ offset = start - acked - 1;
+ } else if (less(acked, end)) {
+ acked = end;
+ }
+ if (si < last_ga->bgack_cnt) {
+ last_ga->start_index = si;
+ r->last_gap = offset;
+ } else {
+ kfree(last_ga);
+ r->last_ga = NULL;
+ r->last_gap = 0;
+ }
+ } else {
+ r->last_gap = 0;
+ }
+ r->acked = acked;
+ } else {
+ kfree(this_ga);
+ }
+
+ return qlen - skb_queue_len(&l->transmq);
+}
+
+/* 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;
+ struct sk_buff_head *dfq = &l->deferdq;
+ u32 defq_len = skb_queue_len(dfq);
+ 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 (defq_len >= 3 && !((defq_len - 3) % 16)) {
+ u16 rcvgap = buf_seqno(skb_peek(dfq)) - l->rcv_nxt;
+
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, 0,
+ rcvgap, 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 = buf_msg(skb);
+ u16 seqno, rcv_nxt, win_lim;
+ int released = 0;
+ int rc = 0;
+
+ /* Verify and update link state */
+ if (unlikely(msg_user(hdr) == LINK_PROTOCOL))
+ return tipc_link_proto_rcv(l, skb, xmitq);
+
+ /* Don't send probe at next timeout expiration */
+ l->silent_intv_cnt = 0;
+
+ do {
+ hdr = buf_msg(skb);
+ seqno = msg_seqno(hdr);
+ rcv_nxt = l->rcv_nxt;
+ win_lim = rcv_nxt + TIPC_MAX_LINK_WIN;
+
+ if (unlikely(!link_is_up(l))) {
+ if (l->state == LINK_ESTABLISHING)
+ rc = TIPC_LINK_UP_EVT;
+ kfree_skb(skb);
+ break;
+ }
+
+ /* Drop if outside receive window */
+ if (unlikely(less(seqno, rcv_nxt) || more(seqno, win_lim))) {
+ l->stats.duplicates++;
+ kfree_skb(skb);
+ break;
+ }
+ released += tipc_link_advance_transmq(l, l, msg_ack(hdr), 0,
+ NULL, NULL, NULL, NULL);
+
+ /* Defer delivery if sequence gap */
+ if (unlikely(seqno != rcv_nxt)) {
+ if (!__tipc_skb_queue_sorted(defq, seqno, skb))
+ l->stats.duplicates++;
+ rc |= tipc_link_build_nack_msg(l, xmitq);
+ break;
+ }
+
+ /* Deliver packet */
+ l->rcv_nxt++;
+ l->stats.recv_pkts++;
+
+ if (unlikely(msg_user(hdr) == TUNNEL_PROTOCOL))
+ rc |= tipc_link_tnl_rcv(l, skb, l->inputq);
+ else if (!tipc_data_input(l, skb, l->inputq))
+ rc |= tipc_link_input(l, skb, l->inputq, &l->reasm_buf);
+ 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 = __tipc_skb_dequeue(defq, l->rcv_nxt)));
+
+ /* Forward queues and wake up waiting users */
+ if (released) {
+ tipc_link_update_cwin(l, released, 0);
+ tipc_link_advance_backlog(l, xmitq);
+ if (unlikely(!skb_queue_empty(&l->wakeupq)))
+ link_prepare_wakeup(l);
+ }
+ 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_mon_state *mstate = &l->mon_state;
+ struct sk_buff_head *dfq = &l->deferdq;
+ struct tipc_link *bcl = l->bc_rcvlink;
+ struct tipc_msg *hdr;
+ struct sk_buff *skb;
+ bool node_up = link_is_up(bcl);
+ u16 glen = 0, bc_rcvgap = 0;
+ 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 ((probe || probe_reply) && !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 + MAX_GAP_ACK_BLKS_SZ,
+ 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);
+ bc_rcvgap = link_bc_rcv_gap(bcl);
+ msg_set_bc_gap(hdr, bc_rcvgap);
+ msg_set_probe(hdr, probe);
+ msg_set_is_keepalive(hdr, probe || probe_reply);
+ if (l->peer_caps & TIPC_GAP_ACK_BLOCK)
+ glen = tipc_build_gap_ack_blks(l, hdr);
+ tipc_mon_prep(l->net, data + glen, &dlen, mstate, l->bearer_id);
+ msg_set_size(hdr, INT_H_SIZE + glen + dlen);
+ skb_trim(skb, INT_H_SIZE + glen + dlen);
+ l->stats.sent_states++;
+ l->rcv_unacked = 0;
+ } else {
+ /* RESET_MSG or ACTIVATE_MSG */
+ if (mtyp == ACTIVATE_MSG) {
+ msg_set_dest_session_valid(hdr, 1);
+ msg_set_dest_session(hdr, l->peer_session);
+ }
+ 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++;
+ if (bc_rcvgap)
+ bcl->stats.sent_nacks++;
+ skb->priority = TC_PRIO_CONTROL;
+ __skb_queue_tail(xmitq, skb);
+ trace_tipc_proto_build(skb, false, l->name);
+}
+
+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_head *fdefq = &tnl->failover_deferdq;
+ struct sk_buff *skb, *tnlskb;
+ struct tipc_msg *hdr, tnlhdr;
+ struct sk_buff_head *queue = &l->transmq;
+ struct sk_buff_head tmpxq, tnlq, frags;
+ u16 pktlen, pktcnt, seqno = l->snd_nxt;
+ bool pktcnt_need_update = false;
+ u16 syncpt;
+ int rc;
+
+ if (!tnl)
+ return;
+
+ __skb_queue_head_init(&tnlq);
+ /* Link Synching:
+ * From now on, send only one single ("dummy") SYNCH message
+ * to peer. The SYNCH message does not contain any data, just
+ * a header conveying the synch point to the peer.
+ */
+ if (mtyp == SYNCH_MSG && (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
+ tnlskb = tipc_msg_create(TUNNEL_PROTOCOL, SYNCH_MSG,
+ INT_H_SIZE, 0, l->addr,
+ tipc_own_addr(l->net),
+ 0, 0, 0);
+ if (!tnlskb) {
+ pr_warn("%sunable to create dummy SYNCH_MSG\n",
+ link_co_err);
+ return;
+ }
+
+ hdr = buf_msg(tnlskb);
+ syncpt = l->snd_nxt + skb_queue_len(&l->backlogq) - 1;
+ msg_set_syncpt(hdr, syncpt);
+ msg_set_bearer_id(hdr, l->peer_bearer_id);
+ __skb_queue_tail(&tnlq, tnlskb);
+ tipc_link_xmit(tnl, &tnlq, xmitq);
+ return;
+ }
+
+ __skb_queue_head_init(&tmpxq);
+ __skb_queue_head_init(&frags);
+ /* 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);
+ if (mtyp == SYNCH_MSG)
+ pktcnt = l->snd_nxt - buf_seqno(skb_peek(&l->transmq));
+ else
+ pktcnt = skb_queue_len(&l->transmq);
+ pktcnt += 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);
+
+ /* Tunnel link MTU is not large enough? This could be
+ * due to:
+ * 1) Link MTU has just changed or set differently;
+ * 2) Or FAILOVER on the top of a SYNCH message
+ *
+ * The 2nd case should not happen if peer supports
+ * TIPC_TUNNEL_ENHANCED
+ */
+ if (pktlen > tnl->mtu - INT_H_SIZE) {
+ if (mtyp == FAILOVER_MSG &&
+ (tnl->peer_caps & TIPC_TUNNEL_ENHANCED)) {
+ rc = tipc_msg_fragment(skb, &tnlhdr, tnl->mtu,
+ &frags);
+ if (rc) {
+ pr_warn("%sunable to frag msg: rc %d\n",
+ link_co_err, rc);
+ return;
+ }
+ pktcnt += skb_queue_len(&frags) - 1;
+ pktcnt_need_update = true;
+ skb_queue_splice_tail_init(&frags, &tnlq);
+ continue;
+ }
+ /* Unluckily, peer doesn't have TIPC_TUNNEL_ENHANCED
+ * => Just warn it and return!
+ */
+ pr_warn_ratelimited("%stoo large msg <%d, %d>: %d!\n",
+ link_co_err, msg_user(hdr),
+ msg_type(hdr), msg_size(hdr));
+ return;
+ }
+
+ 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;
+ }
+
+ if (pktcnt_need_update)
+ skb_queue_walk(&tnlq, skb) {
+ hdr = buf_msg(skb);
+ msg_set_msgcnt(hdr, pktcnt);
+ }
+
+ 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;
+
+ /* Failover the link's deferdq */
+ if (unlikely(!skb_queue_empty(fdefq))) {
+ pr_warn("Link failover deferdq not empty: %d!\n",
+ skb_queue_len(fdefq));
+ __skb_queue_purge(fdefq);
+ }
+ skb_queue_splice_init(&l->deferdq, fdefq);
+ }
+}
+
+/**
+ * tipc_link_failover_prepare() - prepare tnl for link failover
+ *
+ * This is a special version of the precursor - tipc_link_tnl_prepare(),
+ * see the tipc_node_link_failover() for details
+ *
+ * @l: failover link
+ * @tnl: tunnel link
+ * @xmitq: queue for messages to be xmited
+ */
+void tipc_link_failover_prepare(struct tipc_link *l, struct tipc_link *tnl,
+ struct sk_buff_head *xmitq)
+{
+ struct sk_buff_head *fdefq = &tnl->failover_deferdq;
+
+ tipc_link_create_dummy_tnl_msg(tnl, xmitq);
+
+ /* This failover link endpoint was never established before,
+ * so it has not received anything from peer.
+ * Otherwise, it must be a normal failover situation or the
+ * node has entered SELF_DOWN_PEER_LEAVING and both peer nodes
+ * would have to start over from scratch instead.
+ */
+ tnl->drop_point = 1;
+ tnl->failover_reasm_skb = NULL;
+
+ /* Initiate the link's failover deferdq */
+ if (unlikely(!skb_queue_empty(fdefq))) {
+ pr_warn("Link failover deferdq not empty: %d!\n",
+ skb_queue_len(fdefq));
+ __skb_queue_purge(fdefq);
+ }
+}
+
+/* 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);
+ struct tipc_gap_ack_blks *ga = NULL;
+ bool reply = msg_probe(hdr), retransmitted = false;
+ u32 dlen = msg_data_sz(hdr), glen = 0, msg_max;
+ u16 peers_snd_nxt = msg_next_sent(hdr);
+ u16 peers_tol = msg_link_tolerance(hdr);
+ u16 peers_prio = msg_linkprio(hdr);
+ u16 gap = msg_seq_gap(hdr);
+ u16 ack = msg_ack(hdr);
+ u16 rcv_nxt = l->rcv_nxt;
+ u16 rcvgap = 0;
+ int mtyp = msg_type(hdr);
+ int rc = 0, released;
+ char *if_name;
+ void *data;
+
+ trace_tipc_proto_rcv(skb, false, l->name);
+
+ 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);
+
+ if (skb_linearize(skb))
+ goto exit;
+
+ hdr = buf_msg(skb);
+ data = msg_data(hdr);
+
+ if (!tipc_link_validate_msg(l, hdr)) {
+ trace_tipc_skb_dump(skb, false, "PROTO invalid (1)!");
+ trace_tipc_link_dump(l, TIPC_DUMP_NONE, "PROTO invalid (1)!");
+ goto exit;
+ }
+
+ switch (mtyp) {
+ case RESET_MSG:
+ case ACTIVATE_MSG:
+ msg_max = msg_max_pkt(hdr);
+ if (msg_max < tipc_bearer_min_mtu(l->net, l->bearer_id))
+ break;
+ /* 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;
+ }
+
+ /* If this endpoint was re-created while peer was ESTABLISHING
+ * it doesn't know current session number. Force re-synch.
+ */
+ if (mtyp == ACTIVATE_MSG && msg_dest_session_valid(hdr) &&
+ l->session != msg_dest_session(hdr)) {
+ if (less(l->session, msg_dest_session(hdr)))
+ l->session = msg_dest_session(hdr) + 1;
+ 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)
+ l->mtu = msg_max;
+ break;
+
+ case STATE_MSG:
+ /* Validate Gap ACK blocks, drop if invalid */
+ glen = tipc_get_gap_ack_blks(&ga, l, hdr, true);
+ if (glen > dlen)
+ break;
+
+ 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 + glen, dlen - glen, l->addr,
+ &l->mon_state, l->bearer_id);
+
+ /* Send NACK if peer has sent pkts we haven't received yet */
+ if ((reply || msg_is_keepalive(hdr)) &&
+ more(peers_snd_nxt, rcv_nxt) &&
+ !tipc_link_is_synching(l) &&
+ skb_queue_empty(&l->deferdq))
+ rcvgap = peers_snd_nxt - l->rcv_nxt;
+ if (rcvgap || reply)
+ tipc_link_build_proto_msg(l, STATE_MSG, 0, reply,
+ rcvgap, 0, 0, xmitq);
+
+ released = tipc_link_advance_transmq(l, l, ack, gap, ga, xmitq,
+ &retransmitted, &rc);
+ if (gap)
+ l->stats.recv_nacks++;
+ if (released || retransmitted)
+ tipc_link_update_cwin(l, released, retransmitted);
+ if (released)
+ 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;
+}
+
+/* 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)
+{
+ u16 peers_snd_nxt = msg_bc_snd_nxt(hdr);
+ 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;
+
+ /* Ignore if peers_snd_nxt goes beyond receive window */
+ if (more(peers_snd_nxt, l->rcv_nxt + l->window))
+ return rc;
+
+ 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;
+}
+
+int tipc_link_bc_ack_rcv(struct tipc_link *r, u16 acked, u16 gap,
+ struct tipc_gap_ack_blks *ga,
+ struct sk_buff_head *xmitq,
+ struct sk_buff_head *retrq)
+{
+ struct tipc_link *l = r->bc_sndlink;
+ bool unused = false;
+ int rc = 0;
+
+ if (!link_is_up(r) || !r->bc_peer_is_up)
+ return 0;
+
+ if (gap) {
+ l->stats.recv_nacks++;
+ r->stats.recv_nacks++;
+ }
+
+ if (less(acked, r->acked) || (acked == r->acked && !gap && !ga))
+ return 0;
+
+ trace_tipc_link_bc_ack(r, acked, gap, &l->transmq);
+ tipc_link_advance_transmq(l, r, acked, gap, ga, retrq, &unused, &rc);
+
+ tipc_link_advance_backlog(l, xmitq);
+ if (unlikely(!skb_queue_empty(&l->wakeupq)))
+ link_prepare_wakeup(l);
+
+ return rc;
+}
+
+/* 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)) {
+ rc = tipc_link_bc_ack_rcv(l, acked, to - acked, NULL, xmitq,
+ 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 min_win, u32 max_win)
+{
+ int max_bulk = TIPC_MAX_PUBL / (l->mtu / ITEM_SIZE);
+
+ l->min_win = min_win;
+ l->ssthresh = max_win;
+ l->max_win = max_win;
+ l->window = min_win;
+ l->backlog[TIPC_LOW_IMPORTANCE].limit = min_win * 2;
+ l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = min_win * 4;
+ l->backlog[TIPC_HIGH_IMPORTANCE].limit = min_win * 6;
+ l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = min_win * 8;
+ 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_deprecated(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 max_win;
+
+ max_win = nla_get_u32(props[TIPC_NLA_PROP_WIN]);
+ if (max_win < TIPC_DEF_LINK_WIN || max_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_noflag(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_noflag(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_noflag(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_noflag(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,
+ struct tipc_link *bcl)
+{
+ int err;
+ void *hdr;
+ struct nlattr *attrs;
+ struct nlattr *prop;
+ u32 bc_mode = tipc_bcast_get_mode(net);
+ u32 bc_ratio = tipc_bcast_get_broadcast_ratio(net);
+
+ 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_noflag(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_noflag(msg->skb, TIPC_NLA_LINK_PROP);
+ if (!prop)
+ goto attr_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_WIN, bcl->max_win))
+ goto prop_msg_full;
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST, bc_mode))
+ goto prop_msg_full;
+ if (bc_mode & BCLINK_MODE_SEL)
+ if (nla_put_u32(msg->skb, TIPC_NLA_PROP_BROADCAST_RATIO,
+ bc_ratio))
+ 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;
+}
+
+/**
+ * tipc_link_dump - dump TIPC link data
+ * @l: tipc link to be dumped
+ * @dqueues: bitmask to decide if any link queue to be dumped?
+ * - TIPC_DUMP_NONE: don't dump link queues
+ * - TIPC_DUMP_TRANSMQ: dump link transmq queue
+ * - TIPC_DUMP_BACKLOGQ: dump link backlog queue
+ * - TIPC_DUMP_DEFERDQ: dump link deferd queue
+ * - TIPC_DUMP_INPUTQ: dump link input queue
+ * - TIPC_DUMP_WAKEUP: dump link wakeup queue
+ * - TIPC_DUMP_ALL: dump all the link queues above
+ * @buf: returned buffer of dump data in format
+ */
+int tipc_link_dump(struct tipc_link *l, u16 dqueues, char *buf)
+{
+ int i = 0;
+ size_t sz = (dqueues) ? LINK_LMAX : LINK_LMIN;
+ struct sk_buff_head *list;
+ struct sk_buff *hskb, *tskb;
+ u32 len;
+
+ if (!l) {
+ i += scnprintf(buf, sz, "link data: (null)\n");
+ return i;
+ }
+
+ i += scnprintf(buf, sz, "link data: %x", l->addr);
+ i += scnprintf(buf + i, sz - i, " %x", l->state);
+ i += scnprintf(buf + i, sz - i, " %u", l->in_session);
+ i += scnprintf(buf + i, sz - i, " %u", l->session);
+ i += scnprintf(buf + i, sz - i, " %u", l->peer_session);
+ i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt);
+ i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt);
+ i += scnprintf(buf + i, sz - i, " %u", l->snd_nxt_state);
+ i += scnprintf(buf + i, sz - i, " %u", l->rcv_nxt_state);
+ i += scnprintf(buf + i, sz - i, " %x", l->peer_caps);
+ i += scnprintf(buf + i, sz - i, " %u", l->silent_intv_cnt);
+ i += scnprintf(buf + i, sz - i, " %u", l->rst_cnt);
+ i += scnprintf(buf + i, sz - i, " %u", 0);
+ i += scnprintf(buf + i, sz - i, " %u", 0);
+ i += scnprintf(buf + i, sz - i, " %u", l->acked);
+
+ list = &l->transmq;
+ len = skb_queue_len(list);
+ hskb = skb_peek(list);
+ tskb = skb_peek_tail(list);
+ i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
+ (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
+ (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
+
+ list = &l->deferdq;
+ len = skb_queue_len(list);
+ hskb = skb_peek(list);
+ tskb = skb_peek_tail(list);
+ i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
+ (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
+ (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
+
+ list = &l->backlogq;
+ len = skb_queue_len(list);
+ hskb = skb_peek(list);
+ tskb = skb_peek_tail(list);
+ i += scnprintf(buf + i, sz - i, " | %u %u %u", len,
+ (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
+ (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
+
+ list = l->inputq;
+ len = skb_queue_len(list);
+ hskb = skb_peek(list);
+ tskb = skb_peek_tail(list);
+ i += scnprintf(buf + i, sz - i, " | %u %u %u\n", len,
+ (hskb) ? msg_seqno(buf_msg(hskb)) : 0,
+ (tskb) ? msg_seqno(buf_msg(tskb)) : 0);
+
+ if (dqueues & TIPC_DUMP_TRANSMQ) {
+ i += scnprintf(buf + i, sz - i, "transmq: ");
+ i += tipc_list_dump(&l->transmq, false, buf + i);
+ }
+ if (dqueues & TIPC_DUMP_BACKLOGQ) {
+ i += scnprintf(buf + i, sz - i,
+ "backlogq: <%u %u %u %u %u>, ",
+ l->backlog[TIPC_LOW_IMPORTANCE].len,
+ l->backlog[TIPC_MEDIUM_IMPORTANCE].len,
+ l->backlog[TIPC_HIGH_IMPORTANCE].len,
+ l->backlog[TIPC_CRITICAL_IMPORTANCE].len,
+ l->backlog[TIPC_SYSTEM_IMPORTANCE].len);
+ i += tipc_list_dump(&l->backlogq, false, buf + i);
+ }
+ if (dqueues & TIPC_DUMP_DEFERDQ) {
+ i += scnprintf(buf + i, sz - i, "deferdq: ");
+ i += tipc_list_dump(&l->deferdq, false, buf + i);
+ }
+ if (dqueues & TIPC_DUMP_INPUTQ) {
+ i += scnprintf(buf + i, sz - i, "inputq: ");
+ i += tipc_list_dump(l->inputq, false, buf + i);
+ }
+ if (dqueues & TIPC_DUMP_WAKEUP) {
+ i += scnprintf(buf + i, sz - i, "wakeup: ");
+ i += tipc_list_dump(&l->wakeupq, false, buf + i);
+ }
+
+ return i;
+}