/**
* tipc_bcbearer_send - send a packet through the broadcast pseudo-bearer
*
* Send packet over as many bearers as necessary to reach all nodes
* that have joined the broadcast link.
*
* Returns 0 (packet sent successfully) under all circumstances,
* since the broadcast link's pseudo-bearer never blocks
*/
static int tipc_bcbearer_send(struct sk_buff *buf,
struct tipc_bearer *unused1,
struct tipc_media_addr *unused2)
{
int bp_index;
/* Prepare broadcast link message for reliable transmission,
* if first time trying to send it;
* preparation is skipped for broadcast link protocol messages
* since they are sent in an unreliable manner and don't need it
*/
if (likely(!msg_non_seq(buf_msg(buf)))) {
struct tipc_msg *msg;
bcbuf_set_acks(buf, bclink->bcast_nodes.count);
msg = buf_msg(buf);
msg_set_non_seq(msg, 1);
msg_set_mc_netid(msg, tipc_net_id);
bcl->stats.sent_info++;
if (WARN_ON(!bclink->bcast_nodes.count)) {
dump_stack();
return 0;
}
}
/* Send buffer over bearers until all targets reached */
bcbearer->remains = bclink->bcast_nodes;
for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
struct tipc_bearer *b = p;
struct sk_buff *tbuf;
if (!p)
break; /* No more bearers to try */
if (tipc_bearer_blocked(p)) {
if (!s || tipc_bearer_blocked(s))
continue; /* Can't use either bearer */
b = s;
}
tipc_nmap_diff(&bcbearer->remains, &b->nodes,
&bcbearer->remains_new);
if (bcbearer->remains_new.count == bcbearer->remains.count)
continue; /* Nothing added by bearer pair */
if (bp_index == 0) {
/* Use original buffer for first bearer */
tipc_bearer_send(b, buf, &b->bcast_addr);
} else {
/* Avoid concurrent buffer access */
tbuf = pskb_copy(buf, GFP_ATOMIC);
if (!tbuf)
break;
tipc_bearer_send(b, tbuf, &b->bcast_addr);
kfree_skb(tbuf); /* Bearer keeps a clone */
}
/* Swap bearers for next packet */
if (s) {
bcbearer->bpairs[bp_index].primary = s;
bcbearer->bpairs[bp_index].secondary = p;
}
if (bcbearer->remains_new.count == 0)
break; /* All targets reached */
bcbearer->remains = bcbearer->remains_new;
}
return 0;
}
/**
* tipc_bclink_acknowledge - handle acknowledgement of broadcast packets
* @n_ptr: node that sent acknowledgement info
* @acked: broadcast sequence # that has been acknowledged
*
* Node is locked, bc_lock unlocked.
*/
void tipc_bclink_acknowledge(struct tipc_node *n_ptr, u32 acked)
{
struct sk_buff *crs;
struct sk_buff *next;
unsigned int released = 0;
spin_lock_bh(&bc_lock);
/* Bail out if tx queue is empty (no clean up is required) */
crs = bcl->first_out;
if (!crs)
goto exit;
/* Determine which messages need to be acknowledged */
if (acked == INVALID_LINK_SEQ) {
/*
* Contact with specified node has been lost, so need to
* acknowledge sent messages only (if other nodes still exist)
* or both sent and unsent messages (otherwise)
*/
if (bclink->bcast_nodes.count)
acked = bcl->fsm_msg_cnt;
else
acked = bcl->next_out_no;
} else {
/*
* Bail out if specified sequence number does not correspond
* to a message that has been sent and not yet acknowledged
*/
if (less(acked, buf_seqno(crs)) ||
less(bcl->fsm_msg_cnt, acked) ||
less_eq(acked, n_ptr->bclink.acked))
goto exit;
}
/* Skip over packets that node has previously acknowledged */
while (crs && less_eq(buf_seqno(crs), n_ptr->bclink.acked))
crs = crs->next;
/* Update packets that node is now acknowledging */
while (crs && less_eq(buf_seqno(crs), acked)) {
next = crs->next;
if (crs != bcl->next_out)
bcbuf_decr_acks(crs);
else {
bcbuf_set_acks(crs, 0);
bcl->next_out = next;
bclink_set_last_sent();
}
if (bcbuf_acks(crs) == 0) {
bcl->first_out = next;
bcl->out_queue_size--;
kfree_skb(crs);
released = 1;
}
crs = next;
}
n_ptr->bclink.acked = acked;
/* Try resolving broadcast link congestion, if necessary */
if (unlikely(bcl->next_out)) {
tipc_link_push_queue(bcl);
bclink_set_last_sent();
}
if (unlikely(released && !list_empty(&bcl->waiting_ports)))
tipc_link_wakeup_ports(bcl, 0);
exit:
spin_unlock_bh(&bc_lock);
}
static int tipc_bcbearer_send(struct sk_buff *buf,
struct tipc_bearer *unused1,
struct tipc_media_addr *unused2)
{
int bp_index;
/*
* Prepare broadcast link message for reliable transmission,
* if first time trying to send it;
* preparation is skipped for broadcast link protocol messages
* since they are sent in an unreliable manner and don't need it
*/
if (likely(!msg_non_seq(buf_msg(buf)))) {
struct tipc_msg *msg;
bcbuf_set_acks(buf, bclink->bcast_nodes.count);
msg = buf_msg(buf);
msg_set_non_seq(msg, 1);
msg_set_mc_netid(msg, tipc_net_id);
bcl->stats.sent_info++;
if (WARN_ON(!bclink->bcast_nodes.count)) {
dump_stack();
return 0;
}
}
/* Send buffer over bearers until all targets reached */
bcbearer->remains = bclink->bcast_nodes;
for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
struct tipc_bearer *p = bcbearer->bpairs[bp_index].primary;
struct tipc_bearer *s = bcbearer->bpairs[bp_index].secondary;
if (!p)
break; /* no more bearers to try */
tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
if (bcbearer->remains_new.count == bcbearer->remains.count)
continue; /* bearer pair doesn't add anything */
if (p->blocked ||
p->media->send_msg(buf, p, &p->media->bcast_addr)) {
/* unable to send on primary bearer */
if (!s || s->blocked ||
s->media->send_msg(buf, s,
&s->media->bcast_addr)) {
/* unable to send on either bearer */
continue;
}
}
if (s) {
bcbearer->bpairs[bp_index].primary = s;
bcbearer->bpairs[bp_index].secondary = p;
}
if (bcbearer->remains_new.count == 0)
break; /* all targets reached */
bcbearer->remains = bcbearer->remains_new;
}
return 0;
}
static void bcbuf_decr_acks(struct sk_buff *buf)
{
bcbuf_set_acks(buf, bcbuf_acks(buf) - 1);
}
static int tipc_bcbearer_send(struct sk_buff *buf,
struct tipc_bearer *unused1,
struct tipc_media_addr *unused2)
{
static int send_count = 0;
int bp_index;
int swap_time;
/* Prepare buffer for broadcasting (if first time trying to send it) */
if (likely(!msg_non_seq(buf_msg(buf)))) {
struct tipc_msg *msg;
assert(tipc_cltr_bcast_nodes.count != 0);
bcbuf_set_acks(buf, tipc_cltr_bcast_nodes.count);
msg = buf_msg(buf);
msg_set_non_seq(msg, 1);
msg_set_mc_netid(msg, tipc_net_id);
}
/* Determine if bearer pairs should be swapped following this attempt */
if ((swap_time = (++send_count >= 10)))
send_count = 0;
/* Send buffer over bearers until all targets reached */
bcbearer->remains = tipc_cltr_bcast_nodes;
for (bp_index = 0; bp_index < MAX_BEARERS; bp_index++) {
struct bearer *p = bcbearer->bpairs[bp_index].primary;
struct bearer *s = bcbearer->bpairs[bp_index].secondary;
if (!p)
break; /* no more bearers to try */
tipc_nmap_diff(&bcbearer->remains, &p->nodes, &bcbearer->remains_new);
if (bcbearer->remains_new.count == bcbearer->remains.count)
continue; /* bearer pair doesn't add anything */
if (!p->publ.blocked &&
!p->media->send_msg(buf, &p->publ, &p->media->bcast_addr)) {
if (swap_time && s && !s->publ.blocked)
goto swap;
else
goto update;
}
if (!s || s->publ.blocked ||
s->media->send_msg(buf, &s->publ, &s->media->bcast_addr))
continue; /* unable to send using bearer pair */
swap:
bcbearer->bpairs[bp_index].primary = s;
bcbearer->bpairs[bp_index].secondary = p;
update:
if (bcbearer->remains_new.count == 0)
return 0;
bcbearer->remains = bcbearer->remains_new;
}
/* Unable to reach all targets */
bcbearer->bearer.publ.blocked = 1;
bcl->stats.bearer_congs++;
return 1;
}