#define FLAG_FORWARD_PROGRESS (FLAG_ACKED|FLAG_DATA_SACKED)
#define FLAG_ANY_PROGRESS (FLAG_FORWARD_PROGRESS|FLAG_SND_UNA_ADVANCED)
-#define IsReno(tp) ((tp)->rx_opt.sack_ok == 0)
-#define IsFack(tp) ((tp)->rx_opt.sack_ok & 2)
-#define IsDSack(tp) ((tp)->rx_opt.sack_ok & 4)
-
#define IsSackFrto() (sysctl_tcp_frto == 0x2)
#define TCP_REMNANT (TCP_FLAG_FIN|TCP_FLAG_URG|TCP_FLAG_SYN|TCP_FLAG_PSH)
+#define TCP_HP_BITS (~(TCP_RESERVED_BITS|TCP_FLAG_PSH))
/* Adapt the MSS value used to make delayed ack decision to the
* real world.
return icsk->icsk_ack.quick && !icsk->icsk_ack.pingpong;
}
+static inline void TCP_ECN_queue_cwr(struct tcp_sock *tp)
+{
+ if (tp->ecn_flags&TCP_ECN_OK)
+ tp->ecn_flags |= TCP_ECN_QUEUE_CWR;
+}
+
+static inline void TCP_ECN_accept_cwr(struct tcp_sock *tp, struct sk_buff *skb)
+{
+ if (tcp_hdr(skb)->cwr)
+ tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
+}
+
+static inline void TCP_ECN_withdraw_cwr(struct tcp_sock *tp)
+{
+ tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
+}
+
+static inline void TCP_ECN_check_ce(struct tcp_sock *tp, struct sk_buff *skb)
+{
+ if (tp->ecn_flags&TCP_ECN_OK) {
+ if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags))
+ tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
+ /* Funny extension: if ECT is not set on a segment,
+ * it is surely retransmit. It is not in ECN RFC,
+ * but Linux follows this rule. */
+ else if (INET_ECN_is_not_ect((TCP_SKB_CB(skb)->flags)))
+ tcp_enter_quickack_mode((struct sock *)tp);
+ }
+}
+
+static inline void TCP_ECN_rcv_synack(struct tcp_sock *tp, struct tcphdr *th)
+{
+ if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || th->cwr))
+ tp->ecn_flags &= ~TCP_ECN_OK;
+}
+
+static inline void TCP_ECN_rcv_syn(struct tcp_sock *tp, struct tcphdr *th)
+{
+ if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || !th->cwr))
+ tp->ecn_flags &= ~TCP_ECN_OK;
+}
+
+static inline int TCP_ECN_rcv_ecn_echo(struct tcp_sock *tp, struct tcphdr *th)
+{
+ if (th->ece && !th->syn && (tp->ecn_flags&TCP_ECN_OK))
+ return 1;
+ return 0;
+}
+
/* Buffer size and advertised window tuning.
*
* 1. Tuning sk->sk_sndbuf, when connection enters established state.
}
}
+/*
+ * Packet counting of FACK is based on in-order assumptions, therefore TCP
+ * disables it when reordering is detected
+ */
+static void tcp_disable_fack(struct tcp_sock *tp)
+{
+ tp->rx_opt.sack_ok &= ~2;
+}
+
+/* Take a notice that peer is sending DSACKs */
+static void tcp_dsack_seen(struct tcp_sock *tp)
+{
+ tp->rx_opt.sack_ok |= 4;
+}
+
/* Initialize metrics on socket. */
static void tcp_init_metrics(struct sock *sk)
}
if (dst_metric(dst, RTAX_REORDERING) &&
tp->reordering != dst_metric(dst, RTAX_REORDERING)) {
- tp->rx_opt.sack_ok &= ~2;
+ tcp_disable_fack(tp);
tp->reordering = dst_metric(dst, RTAX_REORDERING);
}
/* This exciting event is worth to be remembered. 8) */
if (ts)
NET_INC_STATS_BH(LINUX_MIB_TCPTSREORDER);
- else if (IsReno(tp))
+ else if (tcp_is_reno(tp))
NET_INC_STATS_BH(LINUX_MIB_TCPRENOREORDER);
- else if (IsFack(tp))
+ else if (tcp_is_fack(tp))
NET_INC_STATS_BH(LINUX_MIB_TCPFACKREORDER);
else
NET_INC_STATS_BH(LINUX_MIB_TCPSACKREORDER);
tp->sacked_out,
tp->undo_marker ? tp->undo_retrans : 0);
#endif
- /* Disable FACK yet. */
- tp->rx_opt.sack_ok &= ~2;
+ tcp_disable_fack(tp);
}
}
* for retransmitted and already SACKed segment -> reordering..
* Both of these heuristics are not used in Loss state, when we cannot
* account for retransmits accurately.
+ *
+ * SACK block validation.
+ * ----------------------
+ *
+ * SACK block range validation checks that the received SACK block fits to
+ * the expected sequence limits, i.e., it is between SND.UNA and SND.NXT.
+ * Note that SND.UNA is not included to the range though being valid because
+ * it means that the receiver is rather inconsistent with itself (reports
+ * SACK reneging when it should advance SND.UNA).
+ *
+ * Implements also blockage to start_seq wrap-around. Problem lies in the
+ * fact that though start_seq (s) is before end_seq (i.e., not reversed),
+ * there's no guarantee that it will be before snd_nxt (n). The problem
+ * happens when start_seq resides between end_seq wrap (e_w) and snd_nxt
+ * wrap (s_w):
+ *
+ * <- outs wnd -> <- wrapzone ->
+ * u e n u_w e_w s n_w
+ * | | | | | | |
+ * |<------------+------+----- TCP seqno space --------------+---------->|
+ * ...-- <2^31 ->| |<--------...
+ * ...---- >2^31 ------>| |<--------...
+ *
+ * Current code wouldn't be vulnerable but it's better still to discard such
+ * crazy SACK blocks. Doing this check for start_seq alone closes somewhat
+ * similar case (end_seq after snd_nxt wrap) as earlier reversed check in
+ * snd_nxt wrap -> snd_una region will then become "well defined", i.e.,
+ * equal to the ideal case (infinite seqno space without wrap caused issues).
+ *
+ * With D-SACK the lower bound is extended to cover sequence space below
+ * SND.UNA down to undo_marker, which is the last point of interest. Yet
+ * again, DSACK block must not to go across snd_una (for the same reason as
+ * for the normal SACK blocks, explained above). But there all simplicity
+ * ends, TCP might receive valid D-SACKs below that. As long as they reside
+ * fully below undo_marker they do not affect behavior in anyway and can
+ * therefore be safely ignored. In rare cases (which are more or less
+ * theoretical ones), the D-SACK will nicely cross that boundary due to skb
+ * fragmentation and packet reordering past skb's retransmission. To consider
+ * them correctly, the acceptable range must be extended even more though
+ * the exact amount is rather hard to quantify. However, tp->max_window can
+ * be used as an exaggerated estimate.
*/
+static int tcp_is_sackblock_valid(struct tcp_sock *tp, int is_dsack,
+ u32 start_seq, u32 end_seq)
+{
+ /* Too far in future, or reversed (interpretation is ambiguous) */
+ if (after(end_seq, tp->snd_nxt) || !before(start_seq, end_seq))
+ return 0;
+
+ /* Nasty start_seq wrap-around check (see comments above) */
+ if (!before(start_seq, tp->snd_nxt))
+ return 0;
+
+ /* In outstanding window? ...This is valid exit for DSACKs too.
+ * start_seq == snd_una is non-sensical (see comments above)
+ */
+ if (after(start_seq, tp->snd_una))
+ return 1;
+
+ if (!is_dsack || !tp->undo_marker)
+ return 0;
+
+ /* ...Then it's D-SACK, and must reside below snd_una completely */
+ if (!after(end_seq, tp->snd_una))
+ return 0;
+
+ if (!before(start_seq, tp->undo_marker))
+ return 1;
+
+ /* Too old */
+ if (!after(end_seq, tp->undo_marker))
+ return 0;
+
+ /* Undo_marker boundary crossing (overestimates a lot). Known already:
+ * start_seq < undo_marker and end_seq >= undo_marker.
+ */
+ return !before(start_seq, end_seq - tp->max_window);
+}
+
+
+static int tcp_check_dsack(struct tcp_sock *tp, struct sk_buff *ack_skb,
+ struct tcp_sack_block_wire *sp, int num_sacks,
+ u32 prior_snd_una)
+{
+ u32 start_seq_0 = ntohl(get_unaligned(&sp[0].start_seq));
+ u32 end_seq_0 = ntohl(get_unaligned(&sp[0].end_seq));
+ int dup_sack = 0;
+
+ if (before(start_seq_0, TCP_SKB_CB(ack_skb)->ack_seq)) {
+ dup_sack = 1;
+ tcp_dsack_seen(tp);
+ NET_INC_STATS_BH(LINUX_MIB_TCPDSACKRECV);
+ } else if (num_sacks > 1) {
+ u32 end_seq_1 = ntohl(get_unaligned(&sp[1].end_seq));
+ u32 start_seq_1 = ntohl(get_unaligned(&sp[1].start_seq));
+
+ if (!after(end_seq_0, end_seq_1) &&
+ !before(start_seq_0, start_seq_1)) {
+ dup_sack = 1;
+ tcp_dsack_seen(tp);
+ NET_INC_STATS_BH(LINUX_MIB_TCPDSACKOFORECV);
+ }
+ }
+
+ /* D-SACK for already forgotten data... Do dumb counting. */
+ if (dup_sack &&
+ !after(end_seq_0, prior_snd_una) &&
+ after(end_seq_0, tp->undo_marker))
+ tp->undo_retrans--;
+
+ return dup_sack;
+}
+
static int
tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_una)
{
}
prior_fackets = tp->fackets_out;
- /* Check for D-SACK. */
- if (before(ntohl(sp[0].start_seq), TCP_SKB_CB(ack_skb)->ack_seq)) {
+ found_dup_sack = tcp_check_dsack(tp, ack_skb, sp,
+ num_sacks, prior_snd_una);
+ if (found_dup_sack)
flag |= FLAG_DSACKING_ACK;
- found_dup_sack = 1;
- tp->rx_opt.sack_ok |= 4;
- NET_INC_STATS_BH(LINUX_MIB_TCPDSACKRECV);
- } else if (num_sacks > 1 &&
- !after(ntohl(sp[0].end_seq), ntohl(sp[1].end_seq)) &&
- !before(ntohl(sp[0].start_seq), ntohl(sp[1].start_seq))) {
- flag |= FLAG_DSACKING_ACK;
- found_dup_sack = 1;
- tp->rx_opt.sack_ok |= 4;
- NET_INC_STATS_BH(LINUX_MIB_TCPDSACKOFORECV);
- }
-
- /* D-SACK for already forgotten data...
- * Do dumb counting. */
- if (found_dup_sack &&
- !after(ntohl(sp[0].end_seq), prior_snd_una) &&
- after(ntohl(sp[0].end_seq), tp->undo_marker))
- tp->undo_retrans--;
/* Eliminate too old ACKs, but take into
* account more or less fresh ones, they can
int fack_count;
int dup_sack = (found_dup_sack && (i == first_sack_index));
+ if (!tcp_is_sackblock_valid(tp, dup_sack, start_seq, end_seq)) {
+ if (dup_sack) {
+ if (!tp->undo_marker)
+ NET_INC_STATS_BH(LINUX_MIB_TCPDSACKIGNOREDNOUNDO);
+ else
+ NET_INC_STATS_BH(LINUX_MIB_TCPDSACKIGNOREDOLD);
+ } else
+ NET_INC_STATS_BH(LINUX_MIB_TCPSACKDISCARD);
+ continue;
+ }
+
skb = cached_skb;
fack_count = cached_fack_count;
continue;
if ((TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_RETRANS) &&
after(lost_retrans, TCP_SKB_CB(skb)->ack_seq) &&
- (IsFack(tp) ||
+ (tcp_is_fack(tp) ||
!before(lost_retrans,
TCP_SKB_CB(skb)->ack_seq + tp->reordering *
tp->mss_cache))) {
}
}
- tp->left_out = tp->sacked_out + tp->lost_out;
+ tcp_verify_left_out(tp);
if ((reord < tp->fackets_out) && icsk->icsk_ca_state != TCP_CA_Loss &&
(!tp->frto_highmark || after(tp->snd_una, tp->frto_highmark)))
/* F-RTO can only be used if TCP has never retransmitted anything other than
* head (SACK enhanced variant from Appendix B of RFC4138 is more robust here)
*/
+static void tcp_check_reno_reordering(struct sock *sk, const int addend)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ u32 holes;
+
+ holes = max(tp->lost_out, 1U);
+ holes = min(holes, tp->packets_out);
+
+ if ((tp->sacked_out + holes) > tp->packets_out) {
+ tp->sacked_out = tp->packets_out - holes;
+ tcp_update_reordering(sk, tp->packets_out + addend, 0);
+ }
+}
+
+/* Emulate SACKs for SACKless connection: account for a new dupack. */
+
+static void tcp_add_reno_sack(struct sock *sk)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+ tp->sacked_out++;
+ tcp_check_reno_reordering(sk, 0);
+ tcp_verify_left_out(tp);
+}
+
+/* Account for ACK, ACKing some data in Reno Recovery phase. */
+
+static void tcp_remove_reno_sacks(struct sock *sk, int acked)
+{
+ struct tcp_sock *tp = tcp_sk(sk);
+
+ if (acked > 0) {
+ /* One ACK acked hole. The rest eat duplicate ACKs. */
+ if (acked-1 >= tp->sacked_out)
+ tp->sacked_out = 0;
+ else
+ tp->sacked_out -= acked-1;
+ }
+ tcp_check_reno_reordering(sk, acked);
+ tcp_verify_left_out(tp);
+}
+
+static inline void tcp_reset_reno_sack(struct tcp_sock *tp)
+{
+ tp->sacked_out = 0;
+}
+
int tcp_use_frto(struct sock *sk)
{
const struct tcp_sock *tp = tcp_sk(sk);
TCP_SKB_CB(skb)->sacked &= ~TCPCB_SACKED_RETRANS;
tp->retrans_out -= tcp_skb_pcount(skb);
}
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
/* Earlier loss recovery underway (see RFC4138; Appendix B).
* The last condition is necessary at least in tp->frto_counter case.
{
struct tcp_sock *tp = tcp_sk(sk);
struct sk_buff *skb;
- int cnt = 0;
- tp->sacked_out = 0;
tp->lost_out = 0;
- tp->fackets_out = 0;
tp->retrans_out = 0;
+ if (tcp_is_reno(tp))
+ tcp_reset_reno_sack(tp);
tcp_for_write_queue(skb, sk) {
if (skb == tcp_send_head(sk))
break;
- cnt += tcp_skb_pcount(skb);
/*
* Count the retransmission made on RTO correctly (only when
* waiting for the first ACK and did not get it)...
} else {
TCP_SKB_CB(skb)->sacked &= ~(TCPCB_LOST|TCPCB_SACKED_RETRANS);
}
- if (!(TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_ACKED)) {
- /* Do not mark those segments lost that were
- * forward transmitted after RTO
- */
- if (!after(TCP_SKB_CB(skb)->end_seq,
- tp->frto_highmark)) {
- TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
- tp->lost_out += tcp_skb_pcount(skb);
- }
- } else {
- tp->sacked_out += tcp_skb_pcount(skb);
- tp->fackets_out = cnt;
+ /* Don't lost mark skbs that were fwd transmitted after RTO */
+ if (!(TCP_SKB_CB(skb)->sacked&TCPCB_SACKED_ACKED) &&
+ !after(TCP_SKB_CB(skb)->end_seq, tp->frto_highmark)) {
+ TCP_SKB_CB(skb)->sacked |= TCPCB_LOST;
+ tp->lost_out += tcp_skb_pcount(skb);
}
}
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
tp->snd_cwnd = tcp_packets_in_flight(tp) + allowed_segments;
tp->snd_cwnd_cnt = 0;
void tcp_clear_retrans(struct tcp_sock *tp)
{
- tp->left_out = 0;
tp->retrans_out = 0;
tp->fackets_out = 0;
tp->fackets_out = cnt;
}
}
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
tp->reordering = min_t(unsigned int, tp->reordering,
sysctl_tcp_reordering);
static inline int tcp_fackets_out(struct tcp_sock *tp)
{
- return IsReno(tp) ? tp->sacked_out+1 : tp->fackets_out;
+ return tcp_is_reno(tp) ? tp->sacked_out+1 : tp->fackets_out;
}
static inline int tcp_skb_timedout(struct sock *sk, struct sk_buff *skb)
return 0;
}
-/* If we receive more dupacks than we expected counting segments
- * in assumption of absent reordering, interpret this as reordering.
- * The only another reason could be bug in receiver TCP.
- */
-static void tcp_check_reno_reordering(struct sock *sk, const int addend)
-{
- struct tcp_sock *tp = tcp_sk(sk);
- u32 holes;
-
- holes = max(tp->lost_out, 1U);
- holes = min(holes, tp->packets_out);
-
- if ((tp->sacked_out + holes) > tp->packets_out) {
- tp->sacked_out = tp->packets_out - holes;
- tcp_update_reordering(sk, tp->packets_out + addend, 0);
- }
-}
-
-/* Emulate SACKs for SACKless connection: account for a new dupack. */
-
-static void tcp_add_reno_sack(struct sock *sk)
-{
- struct tcp_sock *tp = tcp_sk(sk);
- tp->sacked_out++;
- tcp_check_reno_reordering(sk, 0);
- tcp_sync_left_out(tp);
-}
-
-/* Account for ACK, ACKing some data in Reno Recovery phase. */
-
-static void tcp_remove_reno_sacks(struct sock *sk, int acked)
-{
- struct tcp_sock *tp = tcp_sk(sk);
-
- if (acked > 0) {
- /* One ACK acked hole. The rest eat duplicate ACKs. */
- if (acked-1 >= tp->sacked_out)
- tp->sacked_out = 0;
- else
- tp->sacked_out -= acked-1;
- }
- tcp_check_reno_reordering(sk, acked);
- tcp_sync_left_out(tp);
-}
-
-static inline void tcp_reset_reno_sack(struct tcp_sock *tp)
-{
- tp->sacked_out = 0;
- tp->left_out = tp->lost_out;
-}
-
/* RFC: This is from the original, I doubt that this is necessary at all:
* clear xmit_retrans hint if seq of this skb is beyond hint. How could we
* retransmitted past LOST markings in the first place? I'm not fully sure
if ((tp->retransmit_skb_hint != NULL) &&
before(TCP_SKB_CB(skb)->seq,
TCP_SKB_CB(tp->retransmit_skb_hint)->seq))
- tp->retransmit_skb_hint = skb;
+ tp->retransmit_skb_hint = NULL;
}
/* Mark head of queue up as lost. */
tcp_verify_retransmit_hint(tp, skb);
}
}
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
}
/* Account newly detected lost packet(s) */
{
struct tcp_sock *tp = tcp_sk(sk);
- if (IsFack(tp)) {
+ if (tcp_is_fack(tp)) {
int lost = tp->fackets_out - tp->reordering;
if (lost <= 0)
lost = 1;
* Hence, we can detect timed out packets during fast
* retransmit without falling to slow start.
*/
- if (!IsReno(tp) && tcp_head_timedout(sk)) {
+ if (!tcp_is_reno(tp) && tcp_head_timedout(sk)) {
struct sk_buff *skb;
skb = tp->scoreboard_skb_hint ? tp->scoreboard_skb_hint
tp->scoreboard_skb_hint = skb;
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
}
}
int decr = tp->snd_cwnd_cnt + 1;
if ((flag&(FLAG_ANY_PROGRESS|FLAG_DSACKING_ACK)) ||
- (IsReno(tp) && !(flag&FLAG_NOT_DUP))) {
+ (tcp_is_reno(tp) && !(flag&FLAG_NOT_DUP))) {
tp->snd_cwnd_cnt = decr&1;
decr >>= 1;
printk(KERN_DEBUG "Undo %s %u.%u.%u.%u/%u c%u l%u ss%u/%u p%u\n",
msg,
NIPQUAD(inet->daddr), ntohs(inet->dport),
- tp->snd_cwnd, tp->left_out,
+ tp->snd_cwnd, tcp_left_out(tp),
tp->snd_ssthresh, tp->prior_ssthresh,
tp->packets_out);
}
NET_INC_STATS_BH(LINUX_MIB_TCPFULLUNDO);
tp->undo_marker = 0;
}
- if (tp->snd_una == tp->high_seq && IsReno(tp)) {
+ if (tp->snd_una == tp->high_seq && tcp_is_reno(tp)) {
/* Hold old state until something *above* high_seq
* is ACKed. For Reno it is MUST to prevent false
* fast retransmits (RFC2582). SACK TCP is safe. */
{
struct tcp_sock *tp = tcp_sk(sk);
/* Partial ACK arrived. Force Hoe's retransmit. */
- int failed = IsReno(tp) || tp->fackets_out>tp->reordering;
+ int failed = tcp_is_reno(tp) || tp->fackets_out>tp->reordering;
if (tcp_may_undo(tp)) {
/* Plain luck! Hole if filled with delayed
DBGUNDO(sk, "partial loss");
tp->lost_out = 0;
- tp->left_out = tp->sacked_out;
tcp_undo_cwr(sk, 1);
NET_INC_STATS_BH(LINUX_MIB_TCPLOSSUNDO);
inet_csk(sk)->icsk_retransmits = 0;
tp->undo_marker = 0;
- if (!IsReno(tp))
+ if (tcp_is_sack(tp))
tcp_set_ca_state(sk, TCP_CA_Open);
return 1;
}
{
struct tcp_sock *tp = tcp_sk(sk);
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
if (tp->retrans_out == 0)
tp->retrans_stamp = 0;
if (inet_csk(sk)->icsk_ca_state != TCP_CA_CWR) {
int state = TCP_CA_Open;
- if (tp->left_out || tp->retrans_out || tp->undo_marker)
+ if (tcp_left_out(tp) || tp->retrans_out || tp->undo_marker)
state = TCP_CA_Disorder;
if (inet_csk(sk)->icsk_ca_state != state) {
* tcp_xmit_retransmit_queue().
*/
static void
-tcp_fastretrans_alert(struct sock *sk, int prior_packets, int flag)
+tcp_fastretrans_alert(struct sock *sk, int pkts_acked, int flag)
{
struct inet_connection_sock *icsk = inet_csk(sk);
struct tcp_sock *tp = tcp_sk(sk);
NET_INC_STATS_BH(LINUX_MIB_TCPLOSS);
}
- /* D. Synchronize left_out to current state. */
- tcp_sync_left_out(tp);
+ /* D. Check consistency of the current state. */
+ tcp_verify_left_out(tp);
/* E. Check state exit conditions. State can be terminated
* when high_seq is ACKed. */
if (!tp->undo_marker ||
/* For SACK case do not Open to allow to undo
* catching for all duplicate ACKs. */
- IsReno(tp) || tp->snd_una != tp->high_seq) {
+ tcp_is_reno(tp) || tp->snd_una != tp->high_seq) {
tp->undo_marker = 0;
tcp_set_ca_state(sk, TCP_CA_Open);
}
break;
case TCP_CA_Recovery:
- if (IsReno(tp))
+ if (tcp_is_reno(tp))
tcp_reset_reno_sack(tp);
if (tcp_try_undo_recovery(sk))
return;
switch (icsk->icsk_ca_state) {
case TCP_CA_Recovery:
if (!(flag & FLAG_SND_UNA_ADVANCED)) {
- if (IsReno(tp) && is_dupack)
+ if (tcp_is_reno(tp) && is_dupack)
tcp_add_reno_sack(sk);
- } else {
- int acked = prior_packets - tp->packets_out;
- if (IsReno(tp))
- tcp_remove_reno_sacks(sk, acked);
- do_lost = tcp_try_undo_partial(sk, acked);
- }
+ } else
+ do_lost = tcp_try_undo_partial(sk, pkts_acked);
break;
case TCP_CA_Loss:
if (flag&FLAG_DATA_ACKED)
return;
/* Loss is undone; fall through to processing in Open state. */
default:
- if (IsReno(tp)) {
+ if (tcp_is_reno(tp)) {
if (flag & FLAG_SND_UNA_ADVANCED)
tcp_reset_reno_sack(tp);
if (is_dupack)
/* Otherwise enter Recovery state */
- if (IsReno(tp))
+ if (tcp_is_reno(tp))
NET_INC_STATS_BH(LINUX_MIB_TCPRENORECOVERY);
else
NET_INC_STATS_BH(LINUX_MIB_TCPSACKRECOVERY);
/* Restart timer after forward progress on connection.
* RFC2988 recommends to restart timer to now+rto.
*/
-
-static void tcp_ack_packets_out(struct sock *sk)
+static void tcp_rearm_rto(struct sock *sk)
{
struct tcp_sock *tp = tcp_sk(sk);
last_ackt = skb->tstamp;
}
tcp_dec_pcount_approx(&tp->fackets_out, skb);
- tcp_packets_out_dec(tp, skb);
+ tp->packets_out -= tcp_skb_pcount(skb);
tcp_unlink_write_queue(skb, sk);
sk_stream_free_skb(sk, skb);
clear_all_retrans_hints(tp);
= inet_csk(sk)->icsk_ca_ops;
tcp_ack_update_rtt(sk, acked, seq_rtt);
- tcp_ack_packets_out(sk);
+ tcp_rearm_rto(sk);
+
+ if (tcp_is_reno(tp))
+ tcp_remove_reno_sacks(sk, pkts_acked);
if (ca_ops->pkts_acked) {
s32 rtt_us = -1;
BUG_TRAP((int)tp->sacked_out >= 0);
BUG_TRAP((int)tp->lost_out >= 0);
BUG_TRAP((int)tp->retrans_out >= 0);
- if (!tp->packets_out && tp->rx_opt.sack_ok) {
+ if (!tp->packets_out && tcp_is_sack(tp)) {
const struct inet_connection_sock *icsk = inet_csk(sk);
if (tp->lost_out) {
printk(KERN_DEBUG "Leak l=%u %d\n",
{
struct tcp_sock *tp = tcp_sk(sk);
- tcp_sync_left_out(tp);
+ tcp_verify_left_out(tp);
/* Duplicate the behavior from Loss state (fastretrans_alert) */
if (flag&FLAG_DATA_ACKED)
return 1;
}
- if (!IsSackFrto() || IsReno(tp)) {
+ if (!IsSackFrto() || tcp_is_reno(tp)) {
/* RFC4138 shortcoming in step 2; should also have case c):
* ACK isn't duplicate nor advances window, e.g., opposite dir
* data, winupdate
if ((flag & FLAG_DATA_ACKED) && !frto_cwnd &&
tcp_may_raise_cwnd(sk, flag))
tcp_cong_avoid(sk, ack, prior_in_flight, 0);
- tcp_fastretrans_alert(sk, prior_packets, flag);
+ tcp_fastretrans_alert(sk, prior_packets - tp->packets_out, flag);
} else {
if ((flag & FLAG_DATA_ACKED) && !frto_cwnd)
tcp_cong_avoid(sk, ack, prior_in_flight, 1);
* Probably, we should reset in this case. For now drop them.
*/
__skb_queue_purge(&tp->out_of_order_queue);
- if (tp->rx_opt.sack_ok)
+ if (tcp_is_sack(tp))
tcp_sack_reset(&tp->rx_opt);
sk_stream_mem_reclaim(sk);
static void tcp_dsack_set(struct tcp_sock *tp, u32 seq, u32 end_seq)
{
- if (tp->rx_opt.sack_ok && sysctl_tcp_dsack) {
+ if (tcp_is_sack(tp) && sysctl_tcp_dsack) {
if (before(seq, tp->rcv_nxt))
NET_INC_STATS_BH(LINUX_MIB_TCPDSACKOLDSENT);
else
NET_INC_STATS_BH(LINUX_MIB_DELAYEDACKLOST);
tcp_enter_quickack_mode(sk);
- if (tp->rx_opt.sack_ok && sysctl_tcp_dsack) {
+ if (tcp_is_sack(tp) && sysctl_tcp_dsack) {
u32 end_seq = TCP_SKB_CB(skb)->end_seq;
if (after(TCP_SKB_CB(skb)->end_seq, tp->rcv_nxt))
if (!skb_peek(&tp->out_of_order_queue)) {
/* Initial out of order segment, build 1 SACK. */
- if (tp->rx_opt.sack_ok) {
+ if (tcp_is_sack(tp)) {
tp->rx_opt.num_sacks = 1;
tp->rx_opt.dsack = 0;
tp->rx_opt.eff_sacks = 1;
}
add_sack:
- if (tp->rx_opt.sack_ok)
+ if (tcp_is_sack(tp))
tcp_sack_new_ofo_skb(sk, seq, end_seq);
}
}
* is in a sad state like this, we care only about integrity
* of the connection not performance.
*/
- if (tp->rx_opt.sack_ok)
+ if (tcp_is_sack(tp))
tcp_sack_reset(&tp->rx_opt);
sk_stream_mem_reclaim(sk);
}
tp->tcp_header_len = sizeof(struct tcphdr);
}
- if (tp->rx_opt.sack_ok && sysctl_tcp_fack)
- tp->rx_opt.sack_ok |= 2;
+ if (tcp_is_sack(tp) && sysctl_tcp_fack)
+ tcp_enable_fack(tp);
tcp_mtup_init(sk);
tcp_sync_mss(sk, icsk->icsk_pmtu_cookie);