#include <net/sctp/sm.h>
/* Forward declarations for internal functions. */
+static void sctp_select_active_and_retran_path(struct sctp_association *asoc);
static void sctp_assoc_bh_rcv(struct work_struct *work);
static void sctp_assoc_free_asconf_acks(struct sctp_association *asoc);
static void sctp_assoc_free_asconf_queue(struct sctp_association *asoc);
sctp_transport_cmd_t command,
sctp_sn_error_t error)
{
- struct sctp_transport *t = NULL;
- struct sctp_transport *first;
- struct sctp_transport *second;
struct sctp_ulpevent *event;
struct sockaddr_storage addr;
int spc_state = 0;
return;
}
- /* Generate and send a SCTP_PEER_ADDR_CHANGE notification to the
- * user.
+ /* Generate and send a SCTP_PEER_ADDR_CHANGE notification
+ * to the user.
*/
if (ulp_notify) {
memset(&addr, 0, sizeof(struct sockaddr_storage));
memcpy(&addr, &transport->ipaddr,
transport->af_specific->sockaddr_len);
+
event = sctp_ulpevent_make_peer_addr_change(asoc, &addr,
0, spc_state, error, GFP_ATOMIC);
if (event)
}
/* Select new active and retran paths. */
-
- /* Look for the two most recently used active transports.
- *
- * This code produces the wrong ordering whenever jiffies
- * rolls over, but we still get usable transports, so we don't
- * worry about it.
- */
- first = NULL; second = NULL;
-
- list_for_each_entry(t, &asoc->peer.transport_addr_list,
- transports) {
-
- if ((t->state == SCTP_INACTIVE) ||
- (t->state == SCTP_UNCONFIRMED) ||
- (t->state == SCTP_PF))
- continue;
- if (!first || t->last_time_heard > first->last_time_heard) {
- second = first;
- first = t;
- } else if (!second ||
- t->last_time_heard > second->last_time_heard)
- second = t;
- }
-
- /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
- *
- * By default, an endpoint should always transmit to the
- * primary path, unless the SCTP user explicitly specifies the
- * destination transport address (and possibly source
- * transport address) to use.
- *
- * [If the primary is active but not most recent, bump the most
- * recently used transport.]
- */
- if (((asoc->peer.primary_path->state == SCTP_ACTIVE) ||
- (asoc->peer.primary_path->state == SCTP_UNKNOWN)) &&
- first != asoc->peer.primary_path) {
- second = first;
- first = asoc->peer.primary_path;
- }
-
- if (!second)
- second = first;
- /* If we failed to find a usable transport, just camp on the
- * primary, even if it is inactive.
- */
- if (!first) {
- first = asoc->peer.primary_path;
- second = asoc->peer.primary_path;
- }
-
- /* Set the active and retran transports. */
- asoc->peer.active_path = first;
- asoc->peer.retran_path = second;
+ sctp_select_active_and_retran_path(asoc);
}
/* Hold a reference to an association. */
}
if (chunk->transport)
- chunk->transport->last_time_heard = jiffies;
+ chunk->transport->last_time_heard = ktime_get();
/* Run through the state machine. */
error = sctp_do_sm(net, SCTP_EVENT_T_CHUNK, subtype,
return sctp_trans_state_to_prio_map[trans->state];
}
+static struct sctp_transport *sctp_trans_elect_tie(struct sctp_transport *trans1,
+ struct sctp_transport *trans2)
+{
+ if (trans1->error_count > trans2->error_count) {
+ return trans2;
+ } else if (trans1->error_count == trans2->error_count &&
+ ktime_after(trans2->last_time_heard,
+ trans1->last_time_heard)) {
+ return trans2;
+ } else {
+ return trans1;
+ }
+}
+
static struct sctp_transport *sctp_trans_elect_best(struct sctp_transport *curr,
struct sctp_transport *best)
{
+ u8 score_curr, score_best;
+
if (best == NULL)
return curr;
- return sctp_trans_score(curr) > sctp_trans_score(best) ? curr : best;
+ score_curr = sctp_trans_score(curr);
+ score_best = sctp_trans_score(best);
+
+ /* First, try a score-based selection if both transport states
+ * differ. If we're in a tie, lets try to make a more clever
+ * decision here based on error counts and last time heard.
+ */
+ if (score_curr > score_best)
+ return curr;
+ else if (score_curr == score_best)
+ return sctp_trans_elect_tie(curr, best);
+ else
+ return best;
}
void sctp_assoc_update_retran_path(struct sctp_association *asoc)
__func__, asoc, &asoc->peer.retran_path->ipaddr.sa);
}
+static void sctp_select_active_and_retran_path(struct sctp_association *asoc)
+{
+ struct sctp_transport *trans, *trans_pri = NULL, *trans_sec = NULL;
+ struct sctp_transport *trans_pf = NULL;
+
+ /* Look for the two most recently used active transports. */
+ list_for_each_entry(trans, &asoc->peer.transport_addr_list,
+ transports) {
+ /* Skip uninteresting transports. */
+ if (trans->state == SCTP_INACTIVE ||
+ trans->state == SCTP_UNCONFIRMED)
+ continue;
+ /* Keep track of the best PF transport from our
+ * list in case we don't find an active one.
+ */
+ if (trans->state == SCTP_PF) {
+ trans_pf = sctp_trans_elect_best(trans, trans_pf);
+ continue;
+ }
+ /* For active transports, pick the most recent ones. */
+ if (trans_pri == NULL ||
+ ktime_after(trans->last_time_heard,
+ trans_pri->last_time_heard)) {
+ trans_sec = trans_pri;
+ trans_pri = trans;
+ } else if (trans_sec == NULL ||
+ ktime_after(trans->last_time_heard,
+ trans_sec->last_time_heard)) {
+ trans_sec = trans;
+ }
+ }
+
+ /* RFC 2960 6.4 Multi-Homed SCTP Endpoints
+ *
+ * By default, an endpoint should always transmit to the primary
+ * path, unless the SCTP user explicitly specifies the
+ * destination transport address (and possibly source transport
+ * address) to use. [If the primary is active but not most recent,
+ * bump the most recently used transport.]
+ */
+ if ((asoc->peer.primary_path->state == SCTP_ACTIVE ||
+ asoc->peer.primary_path->state == SCTP_UNKNOWN) &&
+ asoc->peer.primary_path != trans_pri) {
+ trans_sec = trans_pri;
+ trans_pri = asoc->peer.primary_path;
+ }
+
+ /* We did not find anything useful for a possible retransmission
+ * path; either primary path that we found is the the same as
+ * the current one, or we didn't generally find an active one.
+ */
+ if (trans_sec == NULL)
+ trans_sec = trans_pri;
+
+ /* If we failed to find a usable transport, just camp on the
+ * primary or retran, even if they are inactive, if possible
+ * pick a PF iff it's the better choice.
+ */
+ if (trans_pri == NULL) {
+ trans_pri = sctp_trans_elect_best(asoc->peer.primary_path,
+ asoc->peer.retran_path);
+ trans_pri = sctp_trans_elect_best(trans_pri, trans_pf);
+ trans_sec = asoc->peer.primary_path;
+ }
+
+ /* Set the active and retran transports. */
+ asoc->peer.active_path = trans_pri;
+ asoc->peer.retran_path = trans_sec;
+}
+
struct sctp_transport *
sctp_assoc_choose_alter_transport(struct sctp_association *asoc,
struct sctp_transport *last_sent_to)
/* Set an association id for a given association */
int sctp_assoc_set_id(struct sctp_association *asoc, gfp_t gfp)
{
- bool preload = gfp & __GFP_WAIT;
+ bool preload = !!(gfp & __GFP_WAIT);
int ret;
/* If the id is already assigned, keep it. */
projects / deliverable / linux.git / commitdiff
