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Diffstat (limited to '')
| -rw-r--r-- | net/tipc/bcast.c | 578 |
1 files changed, 578 insertions, 0 deletions
diff --git a/net/tipc/bcast.c b/net/tipc/bcast.c new file mode 100644 index 000000000..68107bf92 --- /dev/null +++ b/net/tipc/bcast.c @@ -0,0 +1,578 @@ +/* + * net/tipc/bcast.c: TIPC broadcast code + * + * Copyright (c) 2004-2006, 2014-2017, Ericsson AB + * Copyright (c) 2004, Intel Corporation. + * Copyright (c) 2005, 2010-2011, 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 <linux/tipc_config.h> +#include "socket.h" +#include "msg.h" +#include "bcast.h" +#include "link.h" +#include "name_table.h" + +#define BCLINK_WIN_DEFAULT 50 /* bcast link window size (default) */ +#define BCLINK_WIN_MIN 32 /* bcast minimum link window size */ + +const char tipc_bclink_name[] = "broadcast-link"; + +/** + * struct tipc_bc_base - base structure for keeping broadcast send state + * @link: broadcast send link structure + * @inputq: data input queue; will only carry SOCK_WAKEUP messages + * @dests: array keeping number of reachable destinations per bearer + * @primary_bearer: a bearer having links to all broadcast destinations, if any + * @bcast_support: indicates if primary bearer, if any, supports broadcast + * @rcast_support: indicates if all peer nodes support replicast + * @rc_ratio: dest count as percentage of cluster size where send method changes + * @bc_threshold: calculated from rc_ratio; if dests > threshold use broadcast + */ +struct tipc_bc_base { + struct tipc_link *link; + struct sk_buff_head inputq; + int dests[MAX_BEARERS]; + int primary_bearer; + bool bcast_support; + bool rcast_support; + int rc_ratio; + int bc_threshold; +}; + +static struct tipc_bc_base *tipc_bc_base(struct net *net) +{ + return tipc_net(net)->bcbase; +} + +/* tipc_bcast_get_mtu(): -get the MTU currently used by broadcast link + * Note: the MTU is decremented to give room for a tunnel header, in + * case the message needs to be sent as replicast + */ +int tipc_bcast_get_mtu(struct net *net) +{ + return tipc_link_mtu(tipc_bc_sndlink(net)) - INT_H_SIZE; +} + +void tipc_bcast_disable_rcast(struct net *net) +{ + tipc_bc_base(net)->rcast_support = false; +} + +static void tipc_bcbase_calc_bc_threshold(struct net *net) +{ + struct tipc_bc_base *bb = tipc_bc_base(net); + int cluster_size = tipc_link_bc_peers(tipc_bc_sndlink(net)); + + bb->bc_threshold = 1 + (cluster_size * bb->rc_ratio / 100); +} + +/* tipc_bcbase_select_primary(): find a bearer with links to all destinations, + * if any, and make it primary bearer + */ +static void tipc_bcbase_select_primary(struct net *net) +{ + struct tipc_bc_base *bb = tipc_bc_base(net); + int all_dests = tipc_link_bc_peers(bb->link); + int i, mtu, prim; + + bb->primary_bearer = INVALID_BEARER_ID; + bb->bcast_support = true; + + if (!all_dests) + return; + + for (i = 0; i < MAX_BEARERS; i++) { + if (!bb->dests[i]) + continue; + + mtu = tipc_bearer_mtu(net, i); + if (mtu < tipc_link_mtu(bb->link)) + tipc_link_set_mtu(bb->link, mtu); + bb->bcast_support &= tipc_bearer_bcast_support(net, i); + if (bb->dests[i] < all_dests) + continue; + + bb->primary_bearer = i; + + /* Reduce risk that all nodes select same primary */ + if ((i ^ tipc_own_addr(net)) & 1) + break; + } + prim = bb->primary_bearer; + if (prim != INVALID_BEARER_ID) + bb->bcast_support = tipc_bearer_bcast_support(net, prim); +} + +void tipc_bcast_inc_bearer_dst_cnt(struct net *net, int bearer_id) +{ + struct tipc_bc_base *bb = tipc_bc_base(net); + + tipc_bcast_lock(net); + bb->dests[bearer_id]++; + tipc_bcbase_select_primary(net); + tipc_bcast_unlock(net); +} + +void tipc_bcast_dec_bearer_dst_cnt(struct net *net, int bearer_id) +{ + struct tipc_bc_base *bb = tipc_bc_base(net); + + tipc_bcast_lock(net); + bb->dests[bearer_id]--; + tipc_bcbase_select_primary(net); + tipc_bcast_unlock(net); +} + +/* tipc_bcbase_xmit - broadcast a packet queue across one or more bearers + * + * Note that number of reachable destinations, as indicated in the dests[] + * array, may transitionally differ from the number of destinations indicated + * in each sent buffer. We can sustain this. Excess destination nodes will + * drop and never acknowledge the unexpected packets, and missing destinations + * will either require retransmission (if they are just about to be added to + * the bearer), or be removed from the buffer's 'ackers' counter (if they + * just went down) + */ +static void tipc_bcbase_xmit(struct net *net, struct sk_buff_head *xmitq) +{ + int bearer_id; + struct tipc_bc_base *bb = tipc_bc_base(net); + struct sk_buff *skb, *_skb; + struct sk_buff_head _xmitq; + + if (skb_queue_empty(xmitq)) + return; + + /* The typical case: at least one bearer has links to all nodes */ + bearer_id = bb->primary_bearer; + if (bearer_id >= 0) { + tipc_bearer_bc_xmit(net, bearer_id, xmitq); + return; + } + + /* We have to transmit across all bearers */ + __skb_queue_head_init(&_xmitq); + for (bearer_id = 0; bearer_id < MAX_BEARERS; bearer_id++) { + if (!bb->dests[bearer_id]) + continue; + + skb_queue_walk(xmitq, skb) { + _skb = pskb_copy_for_clone(skb, GFP_ATOMIC); + if (!_skb) + break; + __skb_queue_tail(&_xmitq, _skb); + } + tipc_bearer_bc_xmit(net, bearer_id, &_xmitq); + } + __skb_queue_purge(xmitq); + __skb_queue_purge(&_xmitq); +} + +static void tipc_bcast_select_xmit_method(struct net *net, int dests, + struct tipc_mc_method *method) +{ + struct tipc_bc_base *bb = tipc_bc_base(net); + unsigned long exp = method->expires; + + /* Broadcast supported by used bearer/bearers? */ + if (!bb->bcast_support) { + method->rcast = true; + return; + } + /* Any destinations which don't support replicast ? */ + if (!bb->rcast_support) { + method->rcast = false; + return; + } + /* Can current method be changed ? */ + method->expires = jiffies + TIPC_METHOD_EXPIRE; + if (method->mandatory || time_before(jiffies, exp)) + return; + + /* Determine method to use now */ + method->rcast = dests <= bb->bc_threshold; +} + +/* tipc_bcast_xmit - broadcast the buffer chain to all external nodes + * @net: the applicable net namespace + * @pkts: chain of buffers containing message + * @cong_link_cnt: set to 1 if broadcast link is congested, otherwise 0 + * Consumes the buffer chain. + * Returns 0 if success, otherwise errno: -EHOSTUNREACH,-EMSGSIZE + */ +static int tipc_bcast_xmit(struct net *net, struct sk_buff_head *pkts, + u16 *cong_link_cnt) +{ + struct tipc_link *l = tipc_bc_sndlink(net); + struct sk_buff_head xmitq; + int rc = 0; + + __skb_queue_head_init(&xmitq); + tipc_bcast_lock(net); + if (tipc_link_bc_peers(l)) + rc = tipc_link_xmit(l, pkts, &xmitq); + tipc_bcast_unlock(net); + tipc_bcbase_xmit(net, &xmitq); + __skb_queue_purge(pkts); + if (rc == -ELINKCONG) { + *cong_link_cnt = 1; + rc = 0; + } + return rc; +} + +/* tipc_rcast_xmit - replicate and send a message to given destination nodes + * @net: the applicable net namespace + * @pkts: chain of buffers containing message + * @dests: list of destination nodes + * @cong_link_cnt: returns number of congested links + * @cong_links: returns identities of congested links + * Returns 0 if success, otherwise errno + */ +static int tipc_rcast_xmit(struct net *net, struct sk_buff_head *pkts, + struct tipc_nlist *dests, u16 *cong_link_cnt) +{ + struct tipc_dest *dst, *tmp; + struct sk_buff_head _pkts; + u32 dnode, selector; + + selector = msg_link_selector(buf_msg(skb_peek(pkts))); + __skb_queue_head_init(&_pkts); + + list_for_each_entry_safe(dst, tmp, &dests->list, list) { + dnode = dst->node; + if (!tipc_msg_pskb_copy(dnode, pkts, &_pkts)) + return -ENOMEM; + + /* Any other return value than -ELINKCONG is ignored */ + if (tipc_node_xmit(net, &_pkts, dnode, selector) == -ELINKCONG) + (*cong_link_cnt)++; + } + return 0; +} + +/* tipc_mcast_xmit - deliver message to indicated destination nodes + * and to identified node local sockets + * @net: the applicable net namespace + * @pkts: chain of buffers containing message + * @method: send method to be used + * @dests: destination nodes for message. + * @cong_link_cnt: returns number of encountered congested destination links + * Consumes buffer chain. + * Returns 0 if success, otherwise errno + */ +int tipc_mcast_xmit(struct net *net, struct sk_buff_head *pkts, + struct tipc_mc_method *method, struct tipc_nlist *dests, + u16 *cong_link_cnt) +{ + struct sk_buff_head inputq, localq; + int rc = 0; + + skb_queue_head_init(&inputq); + __skb_queue_head_init(&localq); + + /* Clone packets before they are consumed by next call */ + if (dests->local && !tipc_msg_reassemble(pkts, &localq)) { + rc = -ENOMEM; + goto exit; + } + /* Send according to determined transmit method */ + if (dests->remote) { + tipc_bcast_select_xmit_method(net, dests->remote, method); + if (method->rcast) + rc = tipc_rcast_xmit(net, pkts, dests, cong_link_cnt); + else + rc = tipc_bcast_xmit(net, pkts, cong_link_cnt); + } + + if (dests->local) + tipc_sk_mcast_rcv(net, &localq, &inputq); +exit: + /* This queue should normally be empty by now */ + __skb_queue_purge(pkts); + return rc; +} + +/* tipc_bcast_rcv - receive a broadcast packet, and deliver to rcv link + * + * RCU is locked, no other locks set + */ +int tipc_bcast_rcv(struct net *net, struct tipc_link *l, struct sk_buff *skb) +{ + struct tipc_msg *hdr = buf_msg(skb); + struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq; + struct sk_buff_head xmitq; + int rc; + + __skb_queue_head_init(&xmitq); + + if (msg_mc_netid(hdr) != tipc_netid(net) || !tipc_link_is_up(l)) { + kfree_skb(skb); + return 0; + } + + tipc_bcast_lock(net); + if (msg_user(hdr) == BCAST_PROTOCOL) + rc = tipc_link_bc_nack_rcv(l, skb, &xmitq); + else + rc = tipc_link_rcv(l, skb, NULL); + tipc_bcast_unlock(net); + + tipc_bcbase_xmit(net, &xmitq); + + /* Any socket wakeup messages ? */ + if (!skb_queue_empty(inputq)) + tipc_sk_rcv(net, inputq); + + return rc; +} + +/* tipc_bcast_ack_rcv - receive and handle a broadcast acknowledge + * + * RCU is locked, no other locks set + */ +void tipc_bcast_ack_rcv(struct net *net, struct tipc_link *l, + struct tipc_msg *hdr) +{ + struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq; + u16 acked = msg_bcast_ack(hdr); + struct sk_buff_head xmitq; + + /* Ignore bc acks sent by peer before bcast synch point was received */ + if (msg_bc_ack_invalid(hdr)) + return; + + __skb_queue_head_init(&xmitq); + + tipc_bcast_lock(net); + tipc_link_bc_ack_rcv(l, acked, &xmitq); + tipc_bcast_unlock(net); + + tipc_bcbase_xmit(net, &xmitq); + + /* Any socket wakeup messages ? */ + if (!skb_queue_empty(inputq)) + tipc_sk_rcv(net, inputq); +} + +/* tipc_bcast_synch_rcv - check and update rcv link with peer's send state + * + * RCU is locked, no other locks set + */ +int tipc_bcast_sync_rcv(struct net *net, struct tipc_link *l, + struct tipc_msg *hdr) +{ + struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq; + struct sk_buff_head xmitq; + int rc = 0; + + __skb_queue_head_init(&xmitq); + + tipc_bcast_lock(net); + if (msg_type(hdr) != STATE_MSG) { + tipc_link_bc_init_rcv(l, hdr); + } else if (!msg_bc_ack_invalid(hdr)) { + tipc_link_bc_ack_rcv(l, msg_bcast_ack(hdr), &xmitq); + rc = tipc_link_bc_sync_rcv(l, hdr, &xmitq); + } + tipc_bcast_unlock(net); + + tipc_bcbase_xmit(net, &xmitq); + + /* Any socket wakeup messages ? */ + if (!skb_queue_empty(inputq)) + tipc_sk_rcv(net, inputq); + return rc; +} + +/* tipc_bcast_add_peer - add a peer node to broadcast link and bearer + * + * RCU is locked, node lock is set + */ +void tipc_bcast_add_peer(struct net *net, struct tipc_link *uc_l, + struct sk_buff_head *xmitq) +{ + struct tipc_link *snd_l = tipc_bc_sndlink(net); + + tipc_bcast_lock(net); + tipc_link_add_bc_peer(snd_l, uc_l, xmitq); + tipc_bcbase_select_primary(net); + tipc_bcbase_calc_bc_threshold(net); + tipc_bcast_unlock(net); +} + +/* tipc_bcast_remove_peer - remove a peer node from broadcast link and bearer + * + * RCU is locked, node lock is set + */ +void tipc_bcast_remove_peer(struct net *net, struct tipc_link *rcv_l) +{ + struct tipc_link *snd_l = tipc_bc_sndlink(net); + struct sk_buff_head *inputq = &tipc_bc_base(net)->inputq; + struct sk_buff_head xmitq; + + __skb_queue_head_init(&xmitq); + + tipc_bcast_lock(net); + tipc_link_remove_bc_peer(snd_l, rcv_l, &xmitq); + tipc_bcbase_select_primary(net); + tipc_bcbase_calc_bc_threshold(net); + tipc_bcast_unlock(net); + + tipc_bcbase_xmit(net, &xmitq); + + /* Any socket wakeup messages ? */ + if (!skb_queue_empty(inputq)) + tipc_sk_rcv(net, inputq); +} + +int tipc_bclink_reset_stats(struct net *net) +{ + struct tipc_link *l = tipc_bc_sndlink(net); + + if (!l) + return -ENOPROTOOPT; + + tipc_bcast_lock(net); + tipc_link_reset_stats(l); + tipc_bcast_unlock(net); + return 0; +} + +static int tipc_bc_link_set_queue_limits(struct net *net, u32 limit) +{ + struct tipc_link *l = tipc_bc_sndlink(net); + + if (!l) + return -ENOPROTOOPT; + if (limit < BCLINK_WIN_MIN) + limit = BCLINK_WIN_MIN; + if (limit > TIPC_MAX_LINK_WIN) + return -EINVAL; + tipc_bcast_lock(net); + tipc_link_set_queue_limits(l, limit); + tipc_bcast_unlock(net); + return 0; +} + +int tipc_nl_bc_link_set(struct net *net, struct nlattr *attrs[]) +{ + int err; + u32 win; + struct nlattr *props[TIPC_NLA_PROP_MAX + 1]; + + if (!attrs[TIPC_NLA_LINK_PROP]) + return -EINVAL; + + err = tipc_nl_parse_link_prop(attrs[TIPC_NLA_LINK_PROP], props); + if (err) + return err; + + if (!props[TIPC_NLA_PROP_WIN]) + return -EOPNOTSUPP; + + win = nla_get_u32(props[TIPC_NLA_PROP_WIN]); + + return tipc_bc_link_set_queue_limits(net, win); +} + +int tipc_bcast_init(struct net *net) +{ + struct tipc_net *tn = tipc_net(net); + struct tipc_bc_base *bb = NULL; + struct tipc_link *l = NULL; + + bb = kzalloc(sizeof(*bb), GFP_KERNEL); + if (!bb) + goto enomem; + tn->bcbase = bb; + spin_lock_init(&tipc_net(net)->bclock); + + if (!tipc_link_bc_create(net, 0, 0, + FB_MTU, + BCLINK_WIN_DEFAULT, + 0, + &bb->inputq, + NULL, + NULL, + &l)) + goto enomem; + bb->link = l; + tn->bcl = l; + bb->rc_ratio = 25; + bb->rcast_support = true; + return 0; +enomem: + kfree(bb); + kfree(l); + return -ENOMEM; +} + +void tipc_bcast_stop(struct net *net) +{ + struct tipc_net *tn = net_generic(net, tipc_net_id); + + synchronize_net(); + kfree(tn->bcbase); + kfree(tn->bcl); +} + +void tipc_nlist_init(struct tipc_nlist *nl, u32 self) +{ + memset(nl, 0, sizeof(*nl)); + INIT_LIST_HEAD(&nl->list); + nl->self = self; +} + +void tipc_nlist_add(struct tipc_nlist *nl, u32 node) +{ + if (node == nl->self) + nl->local = true; + else if (tipc_dest_push(&nl->list, node, 0)) + nl->remote++; +} + +void tipc_nlist_del(struct tipc_nlist *nl, u32 node) +{ + if (node == nl->self) + nl->local = false; + else if (tipc_dest_del(&nl->list, node, 0)) + nl->remote--; +} + +void tipc_nlist_purge(struct tipc_nlist *nl) +{ + tipc_dest_list_purge(&nl->list); + nl->remote = 0; + nl->local = false; +} |