diff options
Diffstat (limited to 'net/tipc/link.c')
| -rw-r--r-- | net/tipc/link.c | 2023 |
1 files changed, 2023 insertions, 0 deletions
diff --git a/net/tipc/link.c b/net/tipc/link.c new file mode 100644 index 000000000000..0080699b7cd1 --- /dev/null +++ b/net/tipc/link.c @@ -0,0 +1,2023 @@ +/* + * net/tipc/link.c: TIPC link code + * + * Copyright (c) 1996-2007, 2012-2015, 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 <linux/pkt_sched.h> + +/* + * Error message prefixes + */ +static const char *link_co_err = "Link tunneling error, "; +static const char *link_rst_msg = "Resetting link "; +static const char tipc_bclink_name[] = "broadcast-link"; + +static const struct nla_policy tipc_nl_link_policy[TIPC_NLA_LINK_MAX + 1] = { + [TIPC_NLA_LINK_UNSPEC] = { .type = NLA_UNSPEC }, + [TIPC_NLA_LINK_NAME] = { + .type = NLA_STRING, + .len = TIPC_MAX_LINK_NAME + }, + [TIPC_NLA_LINK_MTU] = { .type = NLA_U32 }, + [TIPC_NLA_LINK_BROADCAST] = { .type = NLA_FLAG }, + [TIPC_NLA_LINK_UP] = { .type = NLA_FLAG }, + [TIPC_NLA_LINK_ACTIVE] = { .type = NLA_FLAG }, + [TIPC_NLA_LINK_PROP] = { .type = NLA_NESTED }, + [TIPC_NLA_LINK_STATS] = { .type = NLA_NESTED }, + [TIPC_NLA_LINK_RX] = { .type = NLA_U32 }, + [TIPC_NLA_LINK_TX] = { .type = NLA_U32 } +}; + +/* Properties valid for media, bearar and link */ +static const struct nla_policy tipc_nl_prop_policy[TIPC_NLA_PROP_MAX + 1] = { + [TIPC_NLA_PROP_UNSPEC] = { .type = NLA_UNSPEC }, + [TIPC_NLA_PROP_PRIO] = { .type = NLA_U32 }, + [TIPC_NLA_PROP_TOL] = { .type = NLA_U32 }, + [TIPC_NLA_PROP_WIN] = { .type = NLA_U32 } +}; + +/* Send states for broadcast NACKs + */ +enum { + BC_NACK_SND_CONDITIONAL, + BC_NACK_SND_UNCONDITIONAL, + BC_NACK_SND_SUPPRESS, +}; + +/* + * Interval between NACKs when packets arrive out of order + */ +#define TIPC_NACK_INTV (TIPC_MIN_LINK_WIN * 2) +/* + * Out-of-range value for link session numbers + */ +#define WILDCARD_SESSION 0x10000 + +/* 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, + u16 rcvgap, int tolerance, int priority, + struct sk_buff_head *xmitq); +static void link_reset_statistics(struct tipc_link *l_ptr); +static void link_print(struct tipc_link *l_ptr, const char *str); +static void 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)); +} + +int tipc_link_is_active(struct tipc_link *l) +{ + return l->active; +} + +void tipc_link_set_active(struct tipc_link *l, bool active) +{ + l->active = active; +} + +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--; + 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; +} + +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; +} + +static u32 link_own_addr(struct tipc_link *l) +{ + return msg_prevnode(l->pmsg); +} + +/** + * 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 ownnode, u32 peer, + 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) +{ + struct tipc_link *l; + struct tipc_msg *hdr; + + l = kzalloc(sizeof(*l), GFP_ATOMIC); + if (!l) + return false; + *link = l; + l->pmsg = (struct tipc_msg *)&l->proto_msg; + hdr = l->pmsg; + tipc_msg_init(ownnode, hdr, LINK_PROTOCOL, RESET_MSG, INT_H_SIZE, peer); + msg_set_size(hdr, sizeof(l->proto_msg)); + msg_set_session(hdr, session); + msg_set_bearer_id(hdr, l->bearer_id); + + /* Note: peer i/f name is completed by reset/activate message */ + sprintf(l->name, "%u.%u.%u:%s-%u.%u.%u:unknown", + tipc_zone(ownnode), tipc_cluster(ownnode), tipc_node(ownnode), + if_name, tipc_zone(peer), tipc_cluster(peer), tipc_node(peer)); + strcpy((char *)msg_data(hdr), if_name); + + l->addr = peer; + l->peer_caps = peer_caps; + l->net = net; + l->peer_session = WILDCARD_SESSION; + l->bearer_id = bearer_id; + l->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 + * @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, 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; + + 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 + */ +/* 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 rc = 0; + int mtyp = STATE_MSG; + bool xmit = false; + bool prb = false; + u16 bc_snt = l->bc_sndlink->snd_nxt - 1; + u16 bc_acked = l->bc_rcvlink->acked; + bool bc_up = link_is_up(l->bc_rcvlink); + + link_profile_stats(l); + + switch (l->state) { + case LINK_ESTABLISHED: + case LINK_SYNCHING: + if (!l->silent_intv_cnt) { + if (bc_up && (bc_acked != bc_snt)) + xmit = true; + } else if (l->silent_intv_cnt <= l->abort_limit) { + xmit = true; + prb = true; + } else { + rc |= tipc_link_fsm_evt(l, LINK_FAILURE_EVT); + } + l->silent_intv_cnt++; + break; + case LINK_RESET: + xmit = true; + mtyp = RESET_MSG; + break; + case LINK_ESTABLISHING: + xmit = true; + mtyp = ACTIVATE_MSG; + break; + case LINK_PEER_RESET: + case LINK_RESETTING: + case LINK_FAILINGOVER: + break; + default: + break; + } + + if (xmit) + tipc_link_build_proto_msg(l, mtyp, prb, 0, 0, 0, xmitq); + + return rc; +} + +/** + * link_schedule_user - schedule a message sender for wakeup after congestion + * @link: congested link + * @list: message that was attempted sent + * Create pseudo msg to send back to user when congestion abates + * Does not consume buffer list + */ +static int link_schedule_user(struct tipc_link *link, struct sk_buff_head *list) +{ + struct tipc_msg *msg = buf_msg(skb_peek(list)); + int imp = msg_importance(msg); + u32 oport = msg_origport(msg); + u32 addr = link_own_addr(link); + struct sk_buff *skb; + + /* This really cannot happen... */ + if (unlikely(imp > TIPC_CRITICAL_IMPORTANCE)) { + pr_warn("%s<%s>, send queue full", link_rst_msg, link->name); + return -ENOBUFS; + } + /* Non-blocking sender: */ + if (TIPC_SKB_CB(skb_peek(list))->wakeup_pending) + return -ELINKCONG; + + /* Create and schedule wakeup pseudo message */ + skb = tipc_msg_create(SOCK_WAKEUP, 0, INT_H_SIZE, 0, + addr, addr, oport, 0, 0); + if (!skb) + return -ENOBUFS; + TIPC_SKB_CB(skb)->chain_sz = skb_queue_len(list); + TIPC_SKB_CB(skb)->chain_imp = imp; + skb_queue_tail(&link->wakeupq, skb); + link->stats.link_congs++; + return -ELINKCONG; +} + +/** + * link_prepare_wakeup - prepare users for wakeup after congestion + * @link: congested link + * Move a number of waiting users, as permitted by available space in + * the send queue, from link wait queue to node wait queue for wakeup + */ +void link_prepare_wakeup(struct tipc_link *l) +{ + int pnd[TIPC_SYSTEM_IMPORTANCE + 1] = {0,}; + int imp, lim; + struct sk_buff *skb, *tmp; + + skb_queue_walk_safe(&l->wakeupq, skb, tmp) { + imp = TIPC_SKB_CB(skb)->chain_imp; + lim = l->window + l->backlog[imp].limit; + pnd[imp] += TIPC_SKB_CB(skb)->chain_sz; + if ((pnd[imp] + l->backlog[imp].len) >= lim) + break; + skb_unlink(skb, &l->wakeupq); + skb_queue_tail(l->inputq, skb); + } +} + +void tipc_link_reset(struct tipc_link *l) +{ + /* Link is down, accept any session */ + l->peer_session = WILDCARD_SESSION; + + /* If peer is up, it only accepts an incremented session number */ + msg_set_session(l->pmsg, msg_session(l->pmsg) + 1); + + /* Prepare for renewed mtu size negotiation */ + l->mtu = l->advertised_mtu; + + /* Clean up all queues and counters: */ + __skb_queue_purge(&l->transmq); + __skb_queue_purge(&l->deferdq); + skb_queue_splice_init(&l->wakeupq, l->inputq); + __skb_queue_purge(&l->backlogq); + l->backlog[TIPC_LOW_IMPORTANCE].len = 0; + l->backlog[TIPC_MEDIUM_IMPORTANCE].len = 0; + l->backlog[TIPC_HIGH_IMPORTANCE].len = 0; + l->backlog[TIPC_CRITICAL_IMPORTANCE].len = 0; + l->backlog[TIPC_SYSTEM_IMPORTANCE].len = 0; + 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->acked = 0; + l->silent_intv_cnt = 0; + l->stats.recv_info = 0; + l->stale_count = 0; + l->bc_peer_is_up = false; + link_reset_statistics(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, except when returning -ELINKCONG, + * since the caller then may want to make more send attempts. + * Returns 0 if success, or errno: -ELINKCONG, -EMSGSIZE or -ENOBUFS + * Messages at TIPC_SYSTEM_IMPORTANCE are always accepted + */ +int tipc_link_xmit(struct tipc_link *l, struct sk_buff_head *list, + struct sk_buff_head *xmitq) +{ + struct tipc_msg *hdr = buf_msg(skb_peek(list)); + unsigned int maxwin = l->window; + unsigned int i, imp = msg_importance(hdr); + unsigned int mtu = l->mtu; + u16 ack = l->rcv_nxt - 1; + u16 seqno = l->snd_nxt; + u16 bc_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, *bskb; + + /* Match msg importance against this and all higher backlog limits: */ + for (i = imp; i <= TIPC_SYSTEM_IMPORTANCE; i++) { + if (unlikely(l->backlog[i].len >= l->backlog[i].limit)) + return link_schedule_user(l, list); + } + if (unlikely(msg_size(hdr) > mtu)) + return -EMSGSIZE; + + /* Prepare each packet for sending, and add to relevant queue: */ + while (skb_queue_len(list)) { + skb = skb_peek(list); + hdr = buf_msg(skb); + msg_set_seqno(hdr, seqno); + msg_set_ack(hdr, ack); + msg_set_bcast_ack(hdr, bc_ack); + + if (likely(skb_queue_len(transmq) < maxwin)) { + _skb = skb_clone(skb, GFP_ATOMIC); + if (!_skb) + return -ENOBUFS; + __skb_dequeue(list); + __skb_queue_tail(transmq, skb); + __skb_queue_tail(xmitq, _skb); + TIPC_SKB_CB(skb)->ackers = l->ackers; + l->rcv_unacked = 0; + seqno++; + continue; + } + if (tipc_msg_bundle(skb_peek_tail(backlogq), hdr, mtu)) { + kfree_skb(__skb_dequeue(list)); + l->stats.sent_bundled++; + continue; + } + if (tipc_msg_make_bundle(&bskb, hdr, mtu, l->addr)) { + kfree_skb(__skb_dequeue(list)); + __skb_queue_tail(backlogq, bskb); + l->backlog[msg_importance(buf_msg(bskb))].len++; + l->stats.sent_bundled++; + l->stats.sent_bundles++; + continue; + } + l->backlog[imp].len += skb_queue_len(list); + skb_queue_splice_tail_init(list, backlogq); + } + l->snd_nxt = seqno; + return 0; +} + +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; + + 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); + l->backlog[msg_importance(hdr)].len--; + __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; + 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, "Resetting 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)); +} + +int tipc_link_retrans(struct tipc_link *l, u16 from, u16 to, + struct sk_buff_head *xmitq) +{ + struct sk_buff *_skb, *skb = skb_peek(&l->transmq); + struct tipc_msg *hdr; + u16 ack = l->rcv_nxt - 1; + u16 bc_ack = l->bc_rcvlink->rcv_nxt - 1; + + if (!skb) + return 0; + + /* Detect repeated retransmit failures on same packet */ + if (likely(l->last_retransm != buf_seqno(skb))) { + l->last_retransm = buf_seqno(skb); + l->stale_count = 1; + } else if (++l->stale_count > 100) { + link_retransmit_failure(l, skb); + return tipc_link_fsm_evt(l, LINK_FAILURE_EVT); + } + + /* Move forward to where retransmission should start */ + skb_queue_walk(&l->transmq, skb) { + if (!less(buf_seqno(skb), from)) + break; + } + + skb_queue_walk_from(&l->transmq, skb) { + if (more(buf_seqno(skb), to)) + break; + hdr = buf_msg(skb); + _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) +{ + switch (msg_user(buf_msg(skb))) { + case TIPC_LOW_IMPORTANCE: + case TIPC_MEDIUM_IMPORTANCE: + case TIPC_HIGH_IMPORTANCE: + case TIPC_CRITICAL_IMPORTANCE: + case CONN_MANAGER: + skb_queue_tail(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_ack_msg: prepare link acknowledge 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_ack_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 ^ link_own_addr(l)) & 0xf) != 0xf) + return 0; + l->rcv_unacked = 0; + return TIPC_LINK_SND_BC_ACK; + } + + /* Unicast ACK */ + l->rcv_unacked = 0; + l->stats.sent_acks++; + tipc_link_build_proto_msg(l, STATE_MSG, 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; + + if (l->state == LINK_ESTABLISHING) + mtyp = ACTIVATE_MSG; + + tipc_link_build_proto_msg(l, mtyp, 0, 0, 0, 0, xmitq); +} + +/* tipc_link_build_nack_msg: prepare link nack message for transmission + */ +static void tipc_link_build_nack_msg(struct tipc_link *l, + struct sk_buff_head *xmitq) +{ + u32 def_cnt = ++l->stats.deferred_recv; + + if (link_is_bc_rcvlink(l)) + return; + + if ((skb_queue_len(&l->deferdq) == 1) || !(def_cnt % TIPC_NACK_INTV)) + tipc_link_build_proto_msg(l, STATE_MSG, 0, 0, 0, 0, xmitq); +} + +/* tipc_link_rcv - process TIPC packets/messages arriving from off-node + * @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)))) { + 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); + tipc_link_build_nack_msg(l, xmitq); + break; + } + + /* Deliver packet */ + l->rcv_nxt++; + l->stats.recv_info++; + 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_ack_msg(l, xmitq); + if (unlikely(rc & ~TIPC_LINK_SND_BC_ACK)) + 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, + u16 rcvgap, int tolerance, int priority, + struct sk_buff_head *xmitq) +{ + struct sk_buff *skb = NULL; + struct tipc_msg *hdr = l->pmsg; + bool node_up = link_is_up(l->bc_rcvlink); + + /* Don't send protocol message during reset or link failover */ + if (tipc_link_is_blocked(l)) + return; + + msg_set_type(hdr, mtyp); + 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, l->bc_rcvlink->rcv_nxt - 1); + 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); + + /* Compatibility: created msg must not be in sequence with pkt flow */ + msg_set_seqno(hdr, l->snd_nxt + U16_MAX / 2); + + if (mtyp == STATE_MSG) { + if (!tipc_link_is_up(l)) + return; + + /* Override rcvgap if there are packets in deferred queue */ + if (!skb_queue_empty(&l->deferdq)) + rcvgap = buf_seqno(skb_peek(&l->deferdq)) - l->rcv_nxt; + if (rcvgap) { + msg_set_seq_gap(hdr, rcvgap); + l->stats.sent_nacks++; + } + msg_set_probe(hdr, probe); + if (probe) + l->stats.sent_probes++; + l->stats.sent_states++; + l->rcv_unacked = 0; + } else { + /* RESET_MSG or ACTIVATE_MSG */ + msg_set_max_pkt(hdr, l->advertised_mtu); + msg_set_ack(hdr, l->rcv_nxt - 1); + msg_set_next_sent(hdr, 1); + } + skb = tipc_buf_acquire(msg_size(hdr)); + if (!skb) + return; + skb_copy_to_linear_data(skb, hdr, msg_size(hdr)); + skb->priority = TC_PRIO_CONTROL; + __skb_queue_tail(xmitq, skb); +} + +/* 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, link_own_addr(l), + 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(link_own_addr(l), &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); + 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_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; + int mtyp = msg_type(hdr); + char *if_name; + int rc = 0; + + if (tipc_link_is_blocked(l) || !xmitq) + goto exit; + + if (link_own_addr(l) > msg_prevnode(hdr)) + l->net_plane = msg_net_plane(hdr); + + switch (mtyp) { + case RESET_MSG: + + /* Ignore duplicate RESET with old session number */ + if ((less_eq(msg_session(hdr), l->peer_session)) && + (l->peer_session != WILDCARD_SESSION)) + break; + /* fall thru' */ + + case ACTIVATE_MSG: + skb_linearize(skb); + hdr = buf_msg(skb); + + /* 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, msg_data(hdr), 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; + + /* 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; + + /* ACTIVATE_MSG serves as PEER_RESET if link is already down */ + if ((mtyp == RESET_MSG) || !link_is_up(l)) + rc = tipc_link_fsm_evt(l, LINK_PEER_RESET_EVT); + + /* ACTIVATE_MSG takes up link if it was already locally reset */ + if ((mtyp == ACTIVATE_MSG) && (l->state == LINK_ESTABLISHING)) + rc = TIPC_LINK_UP_EVT; + + l->peer_session = msg_session(hdr); + l->peer_bearer_id = msg_bearer_id(hdr); + if (l->mtu > msg_max_pkt(hdr)) + l->mtu = msg_max_pkt(hdr); + break; + + case STATE_MSG: + + /* 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->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; + } + + /* 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 || (msg_probe(hdr))) + tipc_link_build_proto_msg(l, STATE_MSG, 0, 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, 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, link_own_addr(l), 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; + 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 + */ +void 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); + + if (!link_is_up(l)) + return; + + if (!msg_peer_node_is_up(hdr)) + return; + + l->bc_peer_is_up = true; + + /* Ignore if peers_snd_nxt goes beyond receive window */ + if (more(peers_snd_nxt, l->rcv_nxt + l->window)) + return; + + if (!more(peers_snd_nxt, l->rcv_nxt)) { + l->nack_state = BC_NACK_SND_CONDITIONAL; + return; + } + + /* 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; + } + + /* 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; + } + + /* 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; +} + +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 + */ +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 == link_own_addr(l)) { + tipc_link_bc_ack_rcv(l, acked, xmitq); + rc = tipc_link_retrans(l->bc_sndlink, 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_PUBLICATIONS / (l->mtu / ITEM_SIZE); + + l->window = win; + l->backlog[TIPC_LOW_IMPORTANCE].limit = win / 2; + l->backlog[TIPC_MEDIUM_IMPORTANCE].limit = win; + l->backlog[TIPC_HIGH_IMPORTANCE].limit = win / 2 * 3; + l->backlog[TIPC_CRITICAL_IMPORTANCE].limit = win * 2; + l->backlog[TIPC_SYSTEM_IMPORTANCE].limit = max_bulk; +} + +/* tipc_link_find_owner - locate owner node of link by link's name + * @net: the applicable net namespace + * @name: pointer to link name string + * @bearer_id: pointer to index in 'node->links' array where the link was found. + * + * Returns pointer to node owning the link, or 0 if no matching link is found. + */ +static struct tipc_node *tipc_link_find_owner(struct net *net, + const char *link_name, + unsigned int *bearer_id) +{ + struct tipc_net *tn = net_generic(net, tipc_net_id); + struct tipc_link *l_ptr; + struct tipc_node *n_ptr; + struct tipc_node *found_node = NULL; + int i; + + *bearer_id = 0; + rcu_read_lock(); + list_for_each_entry_rcu(n_ptr, &tn->node_list, list) { + tipc_node_lock(n_ptr); + for (i = 0; i < MAX_BEARERS; i++) { + l_ptr = n_ptr->links[i].link; + if (l_ptr && !strcmp(l_ptr->name, link_name)) { + *bearer_id = i; + found_node = n_ptr; + break; + } + } + tipc_node_unlock(n_ptr); + if (found_node) + break; + } + rcu_read_unlock(); + + return found_node; +} + +/** + * link_reset_statistics - reset link statistics + * @l_ptr: pointer to link + */ +static void link_reset_statistics(struct tipc_link *l_ptr) +{ + memset(&l_ptr->stats, 0, sizeof(l_ptr->stats)); + l_ptr->stats.sent_info = l_ptr->snd_nxt; + l_ptr->stats.recv_info = l_ptr->rcv_nxt; +} + +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); + 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; +} + +int tipc_nl_link_set(struct sk_buff *skb, struct genl_info *info) +{ + int err; + int res = 0; + int bearer_id; + char *name; + struct tipc_link *link; + struct tipc_node *node; + struct sk_buff_head xmitq; + struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1]; + struct net *net = sock_net(skb->sk); + + __skb_queue_head_init(&xmitq); + + if (!info->attrs[TIPC_NLA_LINK]) + return -EINVAL; + + err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX, + info->attrs[TIPC_NLA_LINK], + tipc_nl_link_policy); + if (err) + return err; + + if (!attrs[TIPC_NLA_LINK_NAME]) + return -EINVAL; + + name = nla_data(attrs[TIPC_NLA_LINK_NAME]); + + if (strcmp(name, tipc_bclink_name) == 0) + return tipc_nl_bc_link_set(net, attrs); + + node = tipc_link_find_owner(net, name, &bearer_id); + if (!node) + return -EINVAL; + + tipc_node_lock(node); + + link = node->links[bearer_id].link; + if (!link) { + res = -EINVAL; + goto out; + } + + if (attrs[TIPC_NLA_LINK_PROP]) { + struct nlattr *props[TIPC_NLA_PROP_MAX + 1]; + + err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], + props); + if (err) { + res = err; + goto out; + } + + if (props[TIPC_NLA_PROP_TOL]) { + u32 tol; + + tol = nla_get_u32(props[TIPC_NLA_PROP_TOL]); + link->tolerance = tol; + tipc_link_build_proto_msg(link, STATE_MSG, 0, 0, tol, 0, &xmitq); + } + if (props[TIPC_NLA_PROP_PRIO]) { + u32 prio; + + prio = nla_get_u32(props[TIPC_NLA_PROP_PRIO]); + link->priority = prio; + tipc_link_build_proto_msg(link, STATE_MSG, 0, 0, 0, prio, &xmitq); + } + if (props[TIPC_NLA_PROP_WIN]) { + u32 win; + + win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); + tipc_link_set_queue_limits(link, win); + } + } + +out: + tipc_node_unlock(node); + tipc_bearer_xmit(net, bearer_id, &xmitq, &node->links[bearer_id].maddr); + return res; +} + +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, s->recv_info}, + {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, s->sent_info}, + {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 */ +static int __tipc_nl_add_link(struct net *net, struct tipc_nl_msg *msg, + struct tipc_link *link, int nlflags) +{ + int err; + void *hdr; + struct nlattr *attrs; + struct nlattr *prop; + struct tipc_net *tn = net_generic(net, tipc_net_id); + + 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(tn->own_addr))) + 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->rcv_nxt)) + goto attr_msg_full; + if (nla_put_u32(msg->skb, TIPC_NLA_LINK_TX, link->snd_nxt)) + 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; +} + +/* Caller should hold node lock */ +static int __tipc_nl_add_node_links(struct net *net, struct tipc_nl_msg *msg, + struct tipc_node *node, u32 *prev_link) +{ + u32 i; + int err; + + for (i = *prev_link; i < MAX_BEARERS; i++) { + *prev_link = i; + + if (!node->links[i].link) + continue; + + err = __tipc_nl_add_link(net, msg, + node->links[i].link, NLM_F_MULTI); + if (err) + return err; + } + *prev_link = 0; + + return 0; +} + +int tipc_nl_link_dump(struct sk_buff *skb, struct netlink_callback *cb) +{ + struct net *net = sock_net(skb->sk); + struct tipc_net *tn = net_generic(net, tipc_net_id); + struct tipc_node *node; + struct tipc_nl_msg msg; + u32 prev_node = cb->args[0]; + u32 prev_link = cb->args[1]; + int done = cb->args[2]; + int err; + + if (done) + return 0; + + msg.skb = skb; + msg.portid = NETLINK_CB(cb->skb).portid; + msg.seq = cb->nlh->nlmsg_seq; + + rcu_read_lock(); + if (prev_node) { + node = tipc_node_find(net, prev_node); + if (!node) { + /* We never set seq or call nl_dump_check_consistent() + * this means that setting prev_seq here will cause the + * consistence check to fail in the netlink callback + * handler. Resulting in the last NLMSG_DONE message + * having the NLM_F_DUMP_INTR flag set. + */ + cb->prev_seq = 1; + goto out; + } + tipc_node_put(node); + + list_for_each_entry_continue_rcu(node, &tn->node_list, + list) { + tipc_node_lock(node); + err = __tipc_nl_add_node_links(net, &msg, node, + &prev_link); + tipc_node_unlock(node); + if (err) + goto out; + + prev_node = node->addr; + } + } else { + err = tipc_nl_add_bc_link(net, &msg); + if (err) + goto out; + + list_for_each_entry_rcu(node, &tn->node_list, list) { + tipc_node_lock(node); + err = __tipc_nl_add_node_links(net, &msg, node, + &prev_link); + tipc_node_unlock(node); + if (err) + goto out; + + prev_node = node->addr; + } + } + done = 1; +out: + rcu_read_unlock(); + + cb->args[0] = prev_node; + cb->args[1] = prev_link; + cb->args[2] = done; + + return skb->len; +} + +int tipc_nl_link_get(struct sk_buff *skb, struct genl_info *info) +{ + struct net *net = genl_info_net(info); + struct tipc_nl_msg msg; + char *name; + int err; + + msg.portid = info->snd_portid; + msg.seq = info->snd_seq; + + if (!info->attrs[TIPC_NLA_LINK_NAME]) + return -EINVAL; + name = nla_data(info->attrs[TIPC_NLA_LINK_NAME]); + + msg.skb = nlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL); + if (!msg.skb) + return -ENOMEM; + + if (strcmp(name, tipc_bclink_name) == 0) { + err = tipc_nl_add_bc_link(net, &msg); + if (err) { + nlmsg_free(msg.skb); + return err; + } + } else { + int bearer_id; + struct tipc_node *node; + struct tipc_link *link; + + node = tipc_link_find_owner(net, name, &bearer_id); + if (!node) + return -EINVAL; + + tipc_node_lock(node); + link = node->links[bearer_id].link; + if (!link) { + tipc_node_unlock(node); + nlmsg_free(msg.skb); + return -EINVAL; + } + + err = __tipc_nl_add_link(net, &msg, link, 0); + tipc_node_unlock(node); + if (err) { + nlmsg_free(msg.skb); + return err; + } + } + + return genlmsg_reply(msg.skb, info); +} + +int tipc_nl_link_reset_stats(struct sk_buff *skb, struct genl_info *info) +{ + int err; + char *link_name; + unsigned int bearer_id; + struct tipc_link *link; + struct tipc_node *node; + struct nlattr *attrs[TIPC_NLA_LINK_MAX + 1]; + struct net *net = sock_net(skb->sk); + + if (!info->attrs[TIPC_NLA_LINK]) + return -EINVAL; + + err = nla_parse_nested(attrs, TIPC_NLA_LINK_MAX, + info->attrs[TIPC_NLA_LINK], + tipc_nl_link_policy); + if (err) + return err; + + if (!attrs[TIPC_NLA_LINK_NAME]) + return -EINVAL; + + link_name = nla_data(attrs[TIPC_NLA_LINK_NAME]); + + if (strcmp(link_name, tipc_bclink_name) == 0) { + err = tipc_bclink_reset_stats(net); + if (err) + return err; + return 0; + } + + node = tipc_link_find_owner(net, link_name, &bearer_id); + if (!node) + return -EINVAL; + + tipc_node_lock(node); + + link = node->links[bearer_id].link; + if (!link) { + tipc_node_unlock(node); + return -EINVAL; + } + + link_reset_statistics(link); + + tipc_node_unlock(node); + + return 0; +} |