cregit-Linux how code gets into the kernel

Release 4.11 net/sctp/ulpqueue.c

Directory: net/sctp
/* SCTP kernel implementation
 * (C) Copyright IBM Corp. 2001, 2004
 * Copyright (c) 1999-2000 Cisco, Inc.
 * Copyright (c) 1999-2001 Motorola, Inc.
 * Copyright (c) 2001 Intel Corp.
 * Copyright (c) 2001 Nokia, Inc.
 * Copyright (c) 2001 La Monte H.P. Yarroll
 *
 * This abstraction carries sctp events to the ULP (sockets).
 *
 * This SCTP implementation is free software;
 * you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 *
 * This SCTP implementation is distributed in the hope that it
 * will be useful, but WITHOUT ANY WARRANTY; without even the implied
 *                 ************************
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNU CC; see the file COPYING.  If not, see
 * <http://www.gnu.org/licenses/>.
 *
 * Please send any bug reports or fixes you make to the
 * email address(es):
 *    lksctp developers <linux-sctp@vger.kernel.org>
 *
 * Written or modified by:
 *    Jon Grimm             <jgrimm@us.ibm.com>
 *    La Monte H.P. Yarroll <piggy@acm.org>
 *    Sridhar Samudrala     <sri@us.ibm.com>
 */

#include <linux/slab.h>
#include <linux/types.h>
#include <linux/skbuff.h>
#include <net/sock.h>
#include <net/busy_poll.h>
#include <net/sctp/structs.h>
#include <net/sctp/sctp.h>
#include <net/sctp/sm.h>

/* Forward declarations for internal helpers.  */
static struct sctp_ulpevent *sctp_ulpq_reasm(struct sctp_ulpq *ulpq,
					      struct sctp_ulpevent *);
static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *,
					      struct sctp_ulpevent *);
static void sctp_ulpq_reasm_drain(struct sctp_ulpq *ulpq);

/* 1st Level Abstractions */

/* Initialize a ULP queue from a block of memory.  */

struct sctp_ulpq *sctp_ulpq_init(struct sctp_ulpq *ulpq, struct sctp_association *asoc) { memset(ulpq, 0, sizeof(struct sctp_ulpq)); ulpq->asoc = asoc; skb_queue_head_init(&ulpq->reasm); skb_queue_head_init(&ulpq->lobby); ulpq->pd_mode = 0; return ulpq; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm5996.72%480.00%
Sridhar Samudrala23.28%120.00%
Total61100.00%5100.00%

/* Flush the reassembly and ordering queues. */
void sctp_ulpq_flush(struct sctp_ulpq *ulpq) { struct sk_buff *skb; struct sctp_ulpevent *event; while ((skb = __skb_dequeue(&ulpq->lobby)) != NULL) { event = sctp_skb2event(skb); sctp_ulpevent_free(event); } while ((skb = __skb_dequeue(&ulpq->reasm)) != NULL) { event = sctp_skb2event(skb); sctp_ulpevent_free(event); } }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm7188.75%350.00%
Andrew Morton45.00%116.67%
Sridhar Samudrala45.00%116.67%
David S. Miller11.25%116.67%
Total80100.00%6100.00%

/* Dispose of a ulpqueue. */
void sctp_ulpq_free(struct sctp_ulpq *ulpq) { sctp_ulpq_flush(ulpq); }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm1493.33%266.67%
David S. Miller16.67%133.33%
Total15100.00%3100.00%

/* Process an incoming DATA chunk. */
int sctp_ulpq_tail_data(struct sctp_ulpq *ulpq, struct sctp_chunk *chunk, gfp_t gfp) { struct sk_buff_head temp; struct sctp_ulpevent *event; int event_eor = 0; /* Create an event from the incoming chunk. */ event = sctp_ulpevent_make_rcvmsg(chunk->asoc, chunk, gfp); if (!event) return -ENOMEM; /* Do reassembly if needed. */ event = sctp_ulpq_reasm(ulpq, event); /* Do ordering if needed. */ if ((event) && (event->msg_flags & MSG_EOR)) { /* Create a temporary list to collect chunks on. */ skb_queue_head_init(&temp); __skb_queue_tail(&temp, sctp_event2skb(event)); event = sctp_ulpq_order(ulpq, event); } /* Send event to the ULP. 'event' is the sctp_ulpevent for * very first SKB on the 'temp' list. */ if (event) { event_eor = (event->msg_flags & MSG_EOR) ? 1 : 0; sctp_ulpq_tail_event(ulpq, event); } return event_eor; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm11280.00%660.00%
Lee A. Roberts2215.71%110.00%
David S. Miller53.57%220.00%
Al Viro10.71%110.00%
Total140100.00%10100.00%

/* Add a new event for propagation to the ULP. */ /* Clear the partial delivery mode for this socket. Note: This * assumes that no association is currently in partial delivery mode. */
int sctp_clear_pd(struct sock *sk, struct sctp_association *asoc) { struct sctp_sock *sp = sctp_sk(sk); if (atomic_dec_and_test(&sp->pd_mode)) { /* This means there are no other associations in PD, so * we can go ahead and clear out the lobby in one shot */ if (!skb_queue_empty(&sp->pd_lobby)) { skb_queue_splice_tail_init(&sp->pd_lobby, &sk->sk_receive_queue); return 1; } } else { /* There are other associations in PD, so we only need to * pull stuff out of the lobby that belongs to the * associations that is exiting PD (all of its notifications * are posted here). */ if (!skb_queue_empty(&sp->pd_lobby) && asoc) { struct sk_buff *skb, *tmp; struct sctp_ulpevent *event; sctp_skb_for_each(skb, &sp->pd_lobby, tmp) { event = sctp_skb2event(skb); if (event->asoc == asoc) { __skb_unlink(skb, &sp->pd_lobby); __skb_queue_tail(&sk->sk_receive_queue, skb); } } } } return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Vladislav Yasevich9463.09%120.00%
Jon Grimm5033.56%120.00%
Arnaldo Carvalho de Melo42.68%240.00%
Marcelo Ricardo Leitner10.67%120.00%
Total149100.00%5100.00%

/* Set the pd_mode on the socket and ulpq */
static void sctp_ulpq_set_pd(struct sctp_ulpq *ulpq) { struct sctp_sock *sp = sctp_sk(ulpq->asoc->base.sk); atomic_inc(&sp->pd_mode); ulpq->pd_mode = 1; }

Contributors

PersonTokensPropCommitsCommitProp
Vladislav Yasevich41100.00%1100.00%
Total41100.00%1100.00%

/* Clear the pd_mode and restart any pending messages waiting for delivery. */
static int sctp_ulpq_clear_pd(struct sctp_ulpq *ulpq) { ulpq->pd_mode = 0; sctp_ulpq_reasm_drain(ulpq); return sctp_clear_pd(ulpq->asoc->base.sk, ulpq->asoc); }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm2976.32%133.33%
Vladislav Yasevich923.68%266.67%
Total38100.00%3100.00%

/* If the SKB of 'event' is on a list, it is the first such member * of that list. */
int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) { struct sock *sk = ulpq->asoc->base.sk; struct sctp_sock *sp = sctp_sk(sk); struct sk_buff_head *queue, *skb_list; struct sk_buff *skb = sctp_event2skb(event); int clear_pd = 0; skb_list = (struct sk_buff_head *) skb->prev; /* If the socket is just going to throw this away, do not * even try to deliver it. */ if (sk->sk_shutdown & RCV_SHUTDOWN && (sk->sk_shutdown & SEND_SHUTDOWN || !sctp_ulpevent_is_notification(event))) goto out_free; if (!sctp_ulpevent_is_notification(event)) { sk_mark_napi_id(sk, skb); sk_incoming_cpu_update(sk); } /* Check if the user wishes to receive this event. */ if (!sctp_ulpevent_is_enabled(event, &sp->subscribe)) goto out_free; /* If we are in partial delivery mode, post to the lobby until * partial delivery is cleared, unless, of course _this_ is * the association the cause of the partial delivery. */ if (atomic_read(&sp->pd_mode) == 0) { queue = &sk->sk_receive_queue; } else { if (ulpq->pd_mode) { /* If the association is in partial delivery, we * need to finish delivering the partially processed * packet before passing any other data. This is * because we don't truly support stream interleaving. */ if ((event->msg_flags & MSG_NOTIFICATION) || (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK))) queue = &sp->pd_lobby; else { clear_pd = event->msg_flags & MSG_EOR; queue = &sk->sk_receive_queue; } } else { /* * If fragment interleave is enabled, we * can queue this to the receive queue instead * of the lobby. */ if (sp->frag_interleave) queue = &sk->sk_receive_queue; else queue = &sp->pd_lobby; } } /* If we are harvesting multiple skbs they will be * collected on a list. */ if (skb_list) skb_queue_splice_tail_init(skb_list, queue); else __skb_queue_tail(queue, skb); /* Did we just complete partial delivery and need to get * rolling again? Move pending data to the receive * queue. */ if (clear_pd) sctp_ulpq_clear_pd(ulpq); if (queue == &sk->sk_receive_queue && !sp->data_ready_signalled) { sp->data_ready_signalled = 1; sk->sk_data_ready(sk); } return 1; out_free: if (skb_list) sctp_queue_purge_ulpevents(skb_list); else sctp_ulpevent_free(event); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm17754.46%631.58%
Vladislav Yasevich3912.00%210.53%
Marcelo Ricardo Leitner3510.77%315.79%
David S. Miller3410.46%210.53%
Neil Horman154.62%15.26%
Xin Long123.69%15.26%
Eric Dumazet72.15%15.26%
Arnaldo Carvalho de Melo41.23%15.26%
Lucas De Marchi10.31%15.26%
Sridhar Samudrala10.31%15.26%
Total325100.00%19100.00%

/* 2nd Level Abstractions */ /* Helper function to store chunks that need to be reassembled. */
static void sctp_ulpq_store_reasm(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) { struct sk_buff *pos; struct sctp_ulpevent *cevent; __u32 tsn, ctsn; tsn = event->tsn; /* See if it belongs at the end. */ pos = skb_peek_tail(&ulpq->reasm); if (!pos) { __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); return; } /* Short circuit just dropping it at the end. */ cevent = sctp_skb2event(pos); ctsn = cevent->tsn; if (TSN_lt(ctsn, tsn)) { __skb_queue_tail(&ulpq->reasm, sctp_event2skb(event)); return; } /* Find the right place in this list. We store them by TSN. */ skb_queue_walk(&ulpq->reasm, pos) { cevent = sctp_skb2event(pos); ctsn = cevent->tsn; if (TSN_lt(tsn, ctsn)) break; } /* Insert before pos. */ __skb_queue_before(&ulpq->reasm, pos, sctp_event2skb(event)); }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm14391.67%562.50%
David S. Miller106.41%225.00%
Sridhar Samudrala31.92%112.50%
Total156100.00%8100.00%

/* Helper function to return an event corresponding to the reassembled * datagram. * This routine creates a re-assembled skb given the first and last skb's * as stored in the reassembly queue. The skb's may be non-linear if the sctp * payload was fragmented on the way and ip had to reassemble them. * We add the rest of skb's to the first skb's fraglist. */
static struct sctp_ulpevent *sctp_make_reassembled_event(struct net *net, struct sk_buff_head *queue, struct sk_buff *f_frag, struct sk_buff *l_frag) { struct sk_buff *pos; struct sk_buff *new = NULL; struct sctp_ulpevent *event; struct sk_buff *pnext, *last; struct sk_buff *list = skb_shinfo(f_frag)->frag_list; /* Store the pointer to the 2nd skb */ if (f_frag == l_frag) pos = NULL; else pos = f_frag->next; /* Get the last skb in the f_frag's frag_list if present. */ for (last = list; list; last = list, list = list->next) ; /* Add the list of remaining fragments to the first fragments * frag_list. */ if (last) last->next = pos; else { if (skb_cloned(f_frag)) { /* This is a cloned skb, we can't just modify * the frag_list. We need a new skb to do that. * Instead of calling skb_unshare(), we'll do it * ourselves since we need to delay the free. */ new = skb_copy(f_frag, GFP_ATOMIC); if (!new) return NULL; /* try again later */ sctp_skb_set_owner_r(new, f_frag->sk); skb_shinfo(new)->frag_list = pos; } else skb_shinfo(f_frag)->frag_list = pos; } /* Remove the first fragment from the reassembly queue. */ __skb_unlink(f_frag, queue); /* if we did unshare, then free the old skb and re-assign */ if (new) { kfree_skb(f_frag); f_frag = new; } while (pos) { pnext = pos->next; /* Update the len and data_len fields of the first fragment. */ f_frag->len += pos->len; f_frag->data_len += pos->len; /* Remove the fragment from the reassembly queue. */ __skb_unlink(pos, queue); /* Break if we have reached the last fragment. */ if (pos == l_frag) break; pos->next = pnext; pos = pnext; } event = sctp_skb2event(f_frag); SCTP_INC_STATS(net, SCTP_MIB_REASMUSRMSGS); return event; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm11141.26%325.00%
Vladislav Yasevich7126.39%216.67%
Sridhar Samudrala6825.28%216.67%
David S. Miller103.72%216.67%
Eric W. Biedermann72.60%18.33%
Hideaki Yoshifuji / 吉藤英明20.74%216.67%
Total269100.00%12100.00%

/* Helper function to check if an incoming chunk has filled up the last * missing fragment in a SCTP datagram and return the corresponding event. */
static struct sctp_ulpevent *sctp_ulpq_retrieve_reassembled(struct sctp_ulpq *ulpq) { struct sk_buff *pos; struct sctp_ulpevent *cevent; struct sk_buff *first_frag = NULL; __u32 ctsn, next_tsn; struct sctp_ulpevent *retval = NULL; struct sk_buff *pd_first = NULL; struct sk_buff *pd_last = NULL; size_t pd_len = 0; struct sctp_association *asoc; u32 pd_point; /* Initialized to 0 just to avoid compiler warning message. Will * never be used with this value. It is referenced only after it * is set when we find the first fragment of a message. */ next_tsn = 0; /* The chunks are held in the reasm queue sorted by TSN. * Walk through the queue sequentially and look for a sequence of * fragmented chunks that complete a datagram. * 'first_frag' and next_tsn are reset when we find a chunk which * is the first fragment of a datagram. Once these 2 fields are set * we expect to find the remaining middle fragments and the last * fragment in order. If not, first_frag is reset to NULL and we * start the next pass when we find another first fragment. * * There is a potential to do partial delivery if user sets * SCTP_PARTIAL_DELIVERY_POINT option. Lets count some things here * to see if can do PD. */ skb_queue_walk(&ulpq->reasm, pos) { cevent = sctp_skb2event(pos); ctsn = cevent->tsn; switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { case SCTP_DATA_FIRST_FRAG: /* If this "FIRST_FRAG" is the first * element in the queue, then count it towards * possible PD. */ if (pos == ulpq->reasm.next) { pd_first = pos; pd_last = pos; pd_len = pos->len; } else { pd_first = NULL; pd_last = NULL; pd_len = 0; } first_frag = pos; next_tsn = ctsn + 1; break; case SCTP_DATA_MIDDLE_FRAG: if ((first_frag) && (ctsn == next_tsn)) { next_tsn++; if (pd_first) { pd_last = pos; pd_len += pos->len; } } else first_frag = NULL; break; case SCTP_DATA_LAST_FRAG: if (first_frag && (ctsn == next_tsn)) goto found; else first_frag = NULL; break; } } asoc = ulpq->asoc; if (pd_first) { /* Make sure we can enter partial deliver. * We can trigger partial delivery only if framgent * interleave is set, or the socket is not already * in partial delivery. */ if (!sctp_sk(asoc->base.sk)->frag_interleave && atomic_read(&sctp_sk(asoc->base.sk)->pd_mode)) goto done; cevent = sctp_skb2event(pd_first); pd_point = sctp_sk(asoc->base.sk)->pd_point; if (pd_point && pd_point <= pd_len) { retval = sctp_make_reassembled_event(sock_net(asoc->base.sk), &ulpq->reasm, pd_first, pd_last); if (retval) sctp_ulpq_set_pd(ulpq); } } done: return retval; found: retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), &ulpq->reasm, first_frag, pos); if (retval) retval->msg_flags |= MSG_EOR; goto done; }

Contributors

PersonTokensPropCommitsCommitProp
Vladislav Yasevich18649.21%110.00%
Jon Grimm16543.65%550.00%
Eric W. Biedermann205.29%110.00%
David S. Miller61.59%220.00%
Sridhar Samudrala10.26%110.00%
Total378100.00%10100.00%

/* Retrieve the next set of fragments of a partial message. */
static struct sctp_ulpevent *sctp_ulpq_retrieve_partial(struct sctp_ulpq *ulpq) { struct sk_buff *pos, *last_frag, *first_frag; struct sctp_ulpevent *cevent; __u32 ctsn, next_tsn; int is_last; struct sctp_ulpevent *retval; /* The chunks are held in the reasm queue sorted by TSN. * Walk through the queue sequentially and look for the first * sequence of fragmented chunks. */ if (skb_queue_empty(&ulpq->reasm)) return NULL; last_frag = first_frag = NULL; retval = NULL; next_tsn = 0; is_last = 0; skb_queue_walk(&ulpq->reasm, pos) { cevent = sctp_skb2event(pos); ctsn = cevent->tsn; switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { case SCTP_DATA_FIRST_FRAG: if (!first_frag) return NULL; goto done; case SCTP_DATA_MIDDLE_FRAG: if (!first_frag) { first_frag = pos; next_tsn = ctsn + 1; last_frag = pos; } else if (next_tsn == ctsn) { next_tsn++; last_frag = pos; } else goto done; break; case SCTP_DATA_LAST_FRAG: if (!first_frag) first_frag = pos; else if (ctsn != next_tsn) goto done; last_frag = pos; is_last = 1; goto done; default: return NULL; } } /* We have the reassembled event. There is no need to look * further. */ done: retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), &ulpq->reasm, first_frag, last_frag); if (retval && is_last) retval->msg_flags |= MSG_EOR; return retval; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm20784.84%450.00%
Lee A. Roberts208.20%112.50%
Eric W. Biedermann114.51%112.50%
David S. Miller52.05%112.50%
Sridhar Samudrala10.41%112.50%
Total244100.00%8100.00%

/* Helper function to reassemble chunks. Hold chunks on the reasm queue that * need reassembling. */
static struct sctp_ulpevent *sctp_ulpq_reasm(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) { struct sctp_ulpevent *retval = NULL; /* Check if this is part of a fragmented message. */ if (SCTP_DATA_NOT_FRAG == (event->msg_flags & SCTP_DATA_FRAG_MASK)) { event->msg_flags |= MSG_EOR; return event; } sctp_ulpq_store_reasm(ulpq, event); if (!ulpq->pd_mode) retval = sctp_ulpq_retrieve_reassembled(ulpq); else { __u32 ctsn, ctsnap; /* Do not even bother unless this is the next tsn to * be delivered. */ ctsn = event->tsn; ctsnap = sctp_tsnmap_get_ctsn(&ulpq->asoc->peer.tsn_map); if (TSN_lte(ctsn, ctsnap)) retval = sctp_ulpq_retrieve_partial(ulpq); } return retval; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm11799.15%375.00%
Sridhar Samudrala10.85%125.00%
Total118100.00%4100.00%

/* Retrieve the first part (sequential fragments) for partial delivery. */
static struct sctp_ulpevent *sctp_ulpq_retrieve_first(struct sctp_ulpq *ulpq) { struct sk_buff *pos, *last_frag, *first_frag; struct sctp_ulpevent *cevent; __u32 ctsn, next_tsn; struct sctp_ulpevent *retval; /* The chunks are held in the reasm queue sorted by TSN. * Walk through the queue sequentially and look for a sequence of * fragmented chunks that start a datagram. */ if (skb_queue_empty(&ulpq->reasm)) return NULL; last_frag = first_frag = NULL; retval = NULL; next_tsn = 0; skb_queue_walk(&ulpq->reasm, pos) { cevent = sctp_skb2event(pos); ctsn = cevent->tsn; switch (cevent->msg_flags & SCTP_DATA_FRAG_MASK) { case SCTP_DATA_FIRST_FRAG: if (!first_frag) { first_frag = pos; next_tsn = ctsn + 1; last_frag = pos; } else goto done; break; case SCTP_DATA_MIDDLE_FRAG: if (!first_frag) return NULL; if (ctsn == next_tsn) { next_tsn++; last_frag = pos; } else goto done; break; case SCTP_DATA_LAST_FRAG: if (!first_frag) return NULL; else goto done; break; default: return NULL; } } /* We have the reassembled event. There is no need to look * further. */ done: retval = sctp_make_reassembled_event(sock_net(ulpq->asoc->base.sk), &ulpq->reasm, first_frag, last_frag); return retval; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm17684.21%450.00%
Lee A. Roberts167.66%112.50%
Eric W. Biedermann115.26%112.50%
David S. Miller52.39%112.50%
Sridhar Samudrala10.48%112.50%
Total209100.00%8100.00%

/* * Flush out stale fragments from the reassembly queue when processing * a Forward TSN. * * RFC 3758, Section 3.6 * * After receiving and processing a FORWARD TSN, the data receiver MUST * take cautions in updating its re-assembly queue. The receiver MUST * remove any partially reassembled message, which is still missing one * or more TSNs earlier than or equal to the new cumulative TSN point. * In the event that the receiver has invoked the partial delivery API, * a notification SHOULD also be generated to inform the upper layer API * that the message being partially delivered will NOT be completed. */
void sctp_ulpq_reasm_flushtsn(struct sctp_ulpq *ulpq, __u32 fwd_tsn) { struct sk_buff *pos, *tmp; struct sctp_ulpevent *event; __u32 tsn; if (skb_queue_empty(&ulpq->reasm)) return; skb_queue_walk_safe(&ulpq->reasm, pos, tmp) { event = sctp_skb2event(pos); tsn = event->tsn; /* Since the entire message must be abandoned by the * sender (item A3 in Section 3.5, RFC 3758), we can * free all fragments on the list that are less then * or equal to ctsn_point */ if (TSN_lte(tsn, fwd_tsn)) { __skb_unlink(pos, &ulpq->reasm); sctp_ulpevent_free(event); } else break; } }

Contributors

PersonTokensPropCommitsCommitProp
Vladislav Yasevich92100.00%1100.00%
Total92100.00%1100.00%

/* * Drain the reassembly queue. If we just cleared parted delivery, it * is possible that the reassembly queue will contain already reassembled * messages. Retrieve any such messages and give them to the user. */
static void sctp_ulpq_reasm_drain(struct sctp_ulpq *ulpq) { struct sctp_ulpevent *event = NULL; struct sk_buff_head temp; if (skb_queue_empty(&ulpq->reasm)) return; while ((event = sctp_ulpq_retrieve_reassembled(ulpq)) != NULL) { /* Do ordering if needed. */ if ((event) && (event->msg_flags & MSG_EOR)) { skb_queue_head_init(&temp); __skb_queue_tail(&temp, sctp_event2skb(event)); event = sctp_ulpq_order(ulpq, event); } /* Send event to the ULP. 'event' is the * sctp_ulpevent for very first SKB on the temp' list. */ if (event) sctp_ulpq_tail_event(ulpq, event); } }

Contributors

PersonTokensPropCommitsCommitProp
Vladislav Yasevich103100.00%1100.00%
Total103100.00%1100.00%

/* Helper function to gather skbs that have possibly become * ordered by an an incoming chunk. */
static void sctp_ulpq_retrieve_ordered(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) { struct sk_buff_head *event_list; struct sk_buff *pos, *tmp; struct sctp_ulpevent *cevent; struct sctp_stream *stream; __u16 sid, csid, cssn; sid = event->stream; stream = ulpq->asoc->stream; event_list = (struct sk_buff_head *) sctp_event2skb(event)->prev; /* We are holding the chunks by stream, by SSN. */ sctp_skb_for_each(pos, &ulpq->lobby, tmp) { cevent = (struct sctp_ulpevent *) pos->cb; csid = cevent->stream; cssn = cevent->ssn; /* Have we gone too far? */ if (csid > sid) break; /* Have we not gone far enough? */ if (csid < sid) continue; if (cssn != sctp_ssn_peek(stream, in, sid)) break; /* Found it, so mark in the stream. */ sctp_ssn_next(stream, in, sid); __skb_unlink(pos, &ulpq->lobby); /* Attach all gathered skbs to the event. */ __skb_queue_tail(event_list, pos); } }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm12877.11%342.86%
David S. Miller2716.27%228.57%
Xin Long84.82%114.29%
Sridhar Samudrala31.81%114.29%
Total166100.00%7100.00%

/* Helper function to store chunks needing ordering. */
static void sctp_ulpq_store_ordered(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) { struct sk_buff *pos; struct sctp_ulpevent *cevent; __u16 sid, csid; __u16 ssn, cssn; pos = skb_peek_tail(&ulpq->lobby); if (!pos) { __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); return; } sid = event->stream; ssn = event->ssn; cevent = (struct sctp_ulpevent *) pos->cb; csid = cevent->stream; cssn = cevent->ssn; if (sid > csid) { __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); return; } if ((sid == csid) && SSN_lt(cssn, ssn)) { __skb_queue_tail(&ulpq->lobby, sctp_event2skb(event)); return; } /* Find the right place in this list. We store them by * stream ID and then by SSN. */ skb_queue_walk(&ulpq->lobby, pos) { cevent = (struct sctp_ulpevent *) pos->cb; csid = cevent->stream; cssn = cevent->ssn; if (csid > sid) break; if (csid == sid && SSN_lt(ssn, cssn)) break; } /* Insert before pos. */ __skb_queue_before(&ulpq->lobby, pos, sctp_event2skb(event)); }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm20892.86%562.50%
David S. Miller104.46%225.00%
Sridhar Samudrala62.68%112.50%
Total224100.00%8100.00%


static struct sctp_ulpevent *sctp_ulpq_order(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event) { __u16 sid, ssn; struct sctp_stream *stream; /* Check if this message needs ordering. */ if (SCTP_DATA_UNORDERED & event->msg_flags) return event; /* Note: The stream ID must be verified before this routine. */ sid = event->stream; ssn = event->ssn; stream = ulpq->asoc->stream; /* Is this the expected SSN for this stream ID? */ if (ssn != sctp_ssn_peek(stream, in, sid)) { /* We've received something out of order, so find where it * needs to be placed. We order by stream and then by SSN. */ sctp_ulpq_store_ordered(ulpq, event); return NULL; } /* Mark that the next chunk has been found. */ sctp_ssn_next(stream, in, sid); /* Go find any other chunks that were waiting for * ordering. */ sctp_ulpq_retrieve_ordered(ulpq, event); return event; }

Contributors

PersonTokensPropCommitsCommitProp
Jon Grimm9284.40%350.00%
David S. Miller87.34%116.67%
Xin Long76.42%116.67%
Sridhar Samudrala21.83%116.67%
Total109100.00%6100.00%

/* Helper function to gather skbs that have possibly become * ordered by forward tsn skipping their dependencies. */
static void sctp_ulpq_reap_ordered(struct sctp_ulpq *ulpq, __u16 sid) { struct sk_buff *pos, *tmp; struct sctp_ulpevent *cevent