mirror of
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1b07a95a5b
Signed-off-by: David S. Miller <davem@davemloft.net>
1286 lines
36 KiB
C
1286 lines
36 KiB
C
/*
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* net/dccp/ccids/ccid3.c
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*
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* Copyright (c) 2005 The University of Waikato, Hamilton, New Zealand.
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* Copyright (c) 2005-6 Ian McDonald <ian.mcdonald@jandi.co.nz>
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*
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* An implementation of the DCCP protocol
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*
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* This code has been developed by the University of Waikato WAND
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* research group. For further information please see http://www.wand.net.nz/
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*
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* This code also uses code from Lulea University, rereleased as GPL by its
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* authors:
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* Copyright (c) 2003 Nils-Erik Mattsson, Joacim Haggmark, Magnus Erixzon
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*
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* Changes to meet Linux coding standards, to make it meet latest ccid3 draft
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* and to make it work as a loadable module in the DCCP stack written by
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* Arnaldo Carvalho de Melo <acme@conectiva.com.br>.
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*
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* Copyright (c) 2005 Arnaldo Carvalho de Melo <acme@conectiva.com.br>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
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*/
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#include "../ccid.h"
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#include "../dccp.h"
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#include "lib/packet_history.h"
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#include "lib/loss_interval.h"
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#include "lib/tfrc.h"
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#include "ccid3.h"
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#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
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static int ccid3_debug;
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#define ccid3_pr_debug(format, a...) DCCP_PR_DEBUG(ccid3_debug, format, ##a)
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#else
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#define ccid3_pr_debug(format, a...)
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#endif
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static struct dccp_tx_hist *ccid3_tx_hist;
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static struct dccp_rx_hist *ccid3_rx_hist;
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static struct dccp_li_hist *ccid3_li_hist;
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/*
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* Transmitter Half-Connection Routines
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*/
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#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
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static const char *ccid3_tx_state_name(enum ccid3_hc_tx_states state)
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{
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static char *ccid3_state_names[] = {
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[TFRC_SSTATE_NO_SENT] = "NO_SENT",
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[TFRC_SSTATE_NO_FBACK] = "NO_FBACK",
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[TFRC_SSTATE_FBACK] = "FBACK",
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[TFRC_SSTATE_TERM] = "TERM",
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};
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return ccid3_state_names[state];
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}
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#endif
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static void ccid3_hc_tx_set_state(struct sock *sk,
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enum ccid3_hc_tx_states state)
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{
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struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
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enum ccid3_hc_tx_states oldstate = hctx->ccid3hctx_state;
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ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
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dccp_role(sk), sk, ccid3_tx_state_name(oldstate),
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ccid3_tx_state_name(state));
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WARN_ON(state == oldstate);
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hctx->ccid3hctx_state = state;
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}
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/*
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* Compute the initial sending rate X_init according to RFC 3390:
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* w_init = min(4 * MSS, max(2 * MSS, 4380 bytes))
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* X_init = w_init / RTT
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* For consistency with other parts of the code, X_init is scaled by 2^6.
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*/
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static inline u64 rfc3390_initial_rate(struct sock *sk)
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{
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const struct dccp_sock *dp = dccp_sk(sk);
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const __u32 w_init = min(4 * dp->dccps_mss_cache,
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max(2 * dp->dccps_mss_cache, 4380U));
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return scaled_div(w_init << 6, ccid3_hc_tx_sk(sk)->ccid3hctx_rtt);
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}
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/*
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* Recalculate t_ipi and delta (should be called whenever X changes)
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*/
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static inline void ccid3_update_send_interval(struct ccid3_hc_tx_sock *hctx)
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{
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/* Calculate new t_ipi = s / X_inst (X_inst is in 64 * bytes/second) */
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hctx->ccid3hctx_t_ipi = scaled_div32(((u64)hctx->ccid3hctx_s) << 6,
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hctx->ccid3hctx_x);
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/* Calculate new delta by delta = min(t_ipi / 2, t_gran / 2) */
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hctx->ccid3hctx_delta = min_t(u32, hctx->ccid3hctx_t_ipi / 2,
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TFRC_OPSYS_HALF_TIME_GRAN);
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ccid3_pr_debug("t_ipi=%u, delta=%u, s=%u, X=%u\n",
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hctx->ccid3hctx_t_ipi, hctx->ccid3hctx_delta,
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hctx->ccid3hctx_s, (unsigned)(hctx->ccid3hctx_x >> 6));
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}
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/*
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* Update X by
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* If (p > 0)
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* X_calc = calcX(s, R, p);
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* X = max(min(X_calc, 2 * X_recv), s / t_mbi);
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* Else
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* If (now - tld >= R)
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* X = max(min(2 * X, 2 * X_recv), s / R);
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* tld = now;
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*
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* Note: X and X_recv are both stored in units of 64 * bytes/second, to support
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* fine-grained resolution of sending rates. This requires scaling by 2^6
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* throughout the code. Only X_calc is unscaled (in bytes/second).
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*
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*/
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static void ccid3_hc_tx_update_x(struct sock *sk, struct timeval *now)
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{
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struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
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__u64 min_rate = 2 * hctx->ccid3hctx_x_recv;
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const __u64 old_x = hctx->ccid3hctx_x;
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/*
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* Handle IDLE periods: do not reduce below RFC3390 initial sending rate
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* when idling [RFC 4342, 5.1]. See also draft-ietf-dccp-rfc3448bis.
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* For consistency with X and X_recv, min_rate is also scaled by 2^6.
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*/
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if (unlikely(hctx->ccid3hctx_idle)) {
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min_rate = rfc3390_initial_rate(sk);
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min_rate = max(min_rate, 2 * hctx->ccid3hctx_x_recv);
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}
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if (hctx->ccid3hctx_p > 0) {
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hctx->ccid3hctx_x = min(((__u64)hctx->ccid3hctx_x_calc) << 6,
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min_rate);
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hctx->ccid3hctx_x = max(hctx->ccid3hctx_x,
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(((__u64)hctx->ccid3hctx_s) << 6) /
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TFRC_T_MBI);
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} else if (timeval_delta(now, &hctx->ccid3hctx_t_ld) -
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(suseconds_t)hctx->ccid3hctx_rtt >= 0) {
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hctx->ccid3hctx_x =
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max(min(2 * hctx->ccid3hctx_x, min_rate),
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scaled_div(((__u64)hctx->ccid3hctx_s) << 6,
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hctx->ccid3hctx_rtt));
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hctx->ccid3hctx_t_ld = *now;
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}
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if (hctx->ccid3hctx_x != old_x) {
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ccid3_pr_debug("X_prev=%u, X_now=%u, X_calc=%u, "
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"X_recv=%u\n", (unsigned)(old_x >> 6),
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(unsigned)(hctx->ccid3hctx_x >> 6),
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hctx->ccid3hctx_x_calc,
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(unsigned)(hctx->ccid3hctx_x_recv >> 6));
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ccid3_update_send_interval(hctx);
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}
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}
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/*
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* Track the mean packet size `s' (cf. RFC 4342, 5.3 and RFC 3448, 4.1)
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* @len: DCCP packet payload size in bytes
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*/
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static inline void ccid3_hc_tx_update_s(struct ccid3_hc_tx_sock *hctx, int len)
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{
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const u16 old_s = hctx->ccid3hctx_s;
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hctx->ccid3hctx_s = old_s == 0 ? len : (9 * old_s + len) / 10;
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if (hctx->ccid3hctx_s != old_s)
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ccid3_update_send_interval(hctx);
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}
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/*
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* Update Window Counter using the algorithm from [RFC 4342, 8.1].
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* The algorithm is not applicable if RTT < 4 microseconds.
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*/
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static inline void ccid3_hc_tx_update_win_count(struct ccid3_hc_tx_sock *hctx,
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struct timeval *now)
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{
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suseconds_t delta;
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u32 quarter_rtts;
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if (unlikely(hctx->ccid3hctx_rtt < 4)) /* avoid divide-by-zero */
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return;
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delta = timeval_delta(now, &hctx->ccid3hctx_t_last_win_count);
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DCCP_BUG_ON(delta < 0);
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quarter_rtts = (u32)delta / (hctx->ccid3hctx_rtt / 4);
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if (quarter_rtts > 0) {
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hctx->ccid3hctx_t_last_win_count = *now;
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hctx->ccid3hctx_last_win_count += min_t(u32, quarter_rtts, 5);
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hctx->ccid3hctx_last_win_count &= 0xF; /* mod 16 */
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ccid3_pr_debug("now at %#X\n", hctx->ccid3hctx_last_win_count);
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}
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}
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static void ccid3_hc_tx_no_feedback_timer(unsigned long data)
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{
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struct sock *sk = (struct sock *)data;
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struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
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struct timeval now;
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unsigned long t_nfb = USEC_PER_SEC / 5;
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bh_lock_sock(sk);
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if (sock_owned_by_user(sk)) {
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/* Try again later. */
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/* XXX: set some sensible MIB */
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goto restart_timer;
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}
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ccid3_pr_debug("%s(%p, state=%s) - entry \n", dccp_role(sk), sk,
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ccid3_tx_state_name(hctx->ccid3hctx_state));
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hctx->ccid3hctx_idle = 1;
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switch (hctx->ccid3hctx_state) {
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case TFRC_SSTATE_NO_FBACK:
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/* RFC 3448, 4.4: Halve send rate directly */
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hctx->ccid3hctx_x = max(hctx->ccid3hctx_x / 2,
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(((__u64)hctx->ccid3hctx_s) << 6) /
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TFRC_T_MBI);
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ccid3_pr_debug("%s(%p, state=%s), updated tx rate to %u "
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"bytes/s\n", dccp_role(sk), sk,
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ccid3_tx_state_name(hctx->ccid3hctx_state),
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(unsigned)(hctx->ccid3hctx_x >> 6));
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/* The value of R is still undefined and so we can not recompute
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* the timout value. Keep initial value as per [RFC 4342, 5]. */
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t_nfb = TFRC_INITIAL_TIMEOUT;
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ccid3_update_send_interval(hctx);
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break;
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case TFRC_SSTATE_FBACK:
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/*
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* Modify the cached value of X_recv [RFC 3448, 4.4]
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*
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* If (p == 0 || X_calc > 2 * X_recv)
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* X_recv = max(X_recv / 2, s / (2 * t_mbi));
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* Else
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* X_recv = X_calc / 4;
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*
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* Note that X_recv is scaled by 2^6 while X_calc is not
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*/
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BUG_ON(hctx->ccid3hctx_p && !hctx->ccid3hctx_x_calc);
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if (hctx->ccid3hctx_p == 0 ||
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(hctx->ccid3hctx_x_calc > (hctx->ccid3hctx_x_recv >> 5))) {
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hctx->ccid3hctx_x_recv =
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max(hctx->ccid3hctx_x_recv / 2,
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(((__u64)hctx->ccid3hctx_s) << 6) /
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(2 * TFRC_T_MBI));
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if (hctx->ccid3hctx_p == 0)
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dccp_timestamp(sk, &now);
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} else {
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hctx->ccid3hctx_x_recv = hctx->ccid3hctx_x_calc;
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hctx->ccid3hctx_x_recv <<= 4;
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}
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/* Now recalculate X [RFC 3448, 4.3, step (4)] */
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ccid3_hc_tx_update_x(sk, &now);
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/*
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* Schedule no feedback timer to expire in
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* max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
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* See comments in packet_recv() regarding the value of t_RTO.
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*/
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t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
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break;
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case TFRC_SSTATE_NO_SENT:
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DCCP_BUG("%s(%p) - Illegal state NO_SENT", dccp_role(sk), sk);
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/* fall through */
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case TFRC_SSTATE_TERM:
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goto out;
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}
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restart_timer:
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sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
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jiffies + usecs_to_jiffies(t_nfb));
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out:
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bh_unlock_sock(sk);
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sock_put(sk);
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}
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/*
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* returns
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* > 0: delay (in msecs) that should pass before actually sending
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* = 0: can send immediately
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* < 0: error condition; do not send packet
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*/
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static int ccid3_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb)
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{
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struct dccp_sock *dp = dccp_sk(sk);
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struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
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struct timeval now;
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suseconds_t delay;
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BUG_ON(hctx == NULL);
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/*
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* This function is called only for Data and DataAck packets. Sending
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* zero-sized Data(Ack)s is theoretically possible, but for congestion
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* control this case is pathological - ignore it.
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*/
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if (unlikely(skb->len == 0))
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return -EBADMSG;
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dccp_timestamp(sk, &now);
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switch (hctx->ccid3hctx_state) {
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case TFRC_SSTATE_NO_SENT:
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sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
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(jiffies +
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usecs_to_jiffies(TFRC_INITIAL_TIMEOUT)));
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hctx->ccid3hctx_last_win_count = 0;
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hctx->ccid3hctx_t_last_win_count = now;
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/* Set t_0 for initial packet */
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hctx->ccid3hctx_t_nom = now;
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hctx->ccid3hctx_s = skb->len;
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/*
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* Use initial RTT sample when available: recommended by erratum
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* to RFC 4342. This implements the initialisation procedure of
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* draft rfc3448bis, section 4.2. Remember, X is scaled by 2^6.
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*/
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if (dp->dccps_syn_rtt) {
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ccid3_pr_debug("SYN RTT = %uus\n", dp->dccps_syn_rtt);
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hctx->ccid3hctx_rtt = dp->dccps_syn_rtt;
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hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
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hctx->ccid3hctx_t_ld = now;
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} else {
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/* Sender does not have RTT sample: X = MSS/second */
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hctx->ccid3hctx_x = dp->dccps_mss_cache;
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hctx->ccid3hctx_x <<= 6;
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}
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ccid3_update_send_interval(hctx);
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ccid3_hc_tx_set_state(sk, TFRC_SSTATE_NO_FBACK);
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break;
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case TFRC_SSTATE_NO_FBACK:
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case TFRC_SSTATE_FBACK:
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delay = timeval_delta(&hctx->ccid3hctx_t_nom, &now);
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ccid3_pr_debug("delay=%ld\n", (long)delay);
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/*
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* Scheduling of packet transmissions [RFC 3448, 4.6]
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*
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* if (t_now > t_nom - delta)
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* // send the packet now
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* else
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* // send the packet in (t_nom - t_now) milliseconds.
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*/
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if (delay - (suseconds_t)hctx->ccid3hctx_delta >= 0)
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return delay / 1000L;
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ccid3_hc_tx_update_win_count(hctx, &now);
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break;
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case TFRC_SSTATE_TERM:
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DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
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return -EINVAL;
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}
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/* prepare to send now (add options etc.) */
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dp->dccps_hc_tx_insert_options = 1;
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DCCP_SKB_CB(skb)->dccpd_ccval = hctx->ccid3hctx_last_win_count;
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hctx->ccid3hctx_idle = 0;
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/* set the nominal send time for the next following packet */
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timeval_add_usecs(&hctx->ccid3hctx_t_nom, hctx->ccid3hctx_t_ipi);
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return 0;
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}
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|
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static void ccid3_hc_tx_packet_sent(struct sock *sk, int more,
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unsigned int len)
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{
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struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
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struct timeval now;
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struct dccp_tx_hist_entry *packet;
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BUG_ON(hctx == NULL);
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ccid3_hc_tx_update_s(hctx, len);
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packet = dccp_tx_hist_entry_new(ccid3_tx_hist, GFP_ATOMIC);
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if (unlikely(packet == NULL)) {
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DCCP_CRIT("packet history - out of memory!");
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return;
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}
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dccp_tx_hist_add_entry(&hctx->ccid3hctx_hist, packet);
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|
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dccp_timestamp(sk, &now);
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packet->dccphtx_tstamp = now;
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packet->dccphtx_seqno = dccp_sk(sk)->dccps_gss;
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packet->dccphtx_rtt = hctx->ccid3hctx_rtt;
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packet->dccphtx_sent = 1;
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}
|
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|
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static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
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{
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struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
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struct ccid3_options_received *opt_recv;
|
|
struct dccp_tx_hist_entry *packet;
|
|
struct timeval now;
|
|
unsigned long t_nfb;
|
|
u32 pinv, r_sample;
|
|
|
|
BUG_ON(hctx == NULL);
|
|
|
|
/* we are only interested in ACKs */
|
|
if (!(DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK ||
|
|
DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_DATAACK))
|
|
return;
|
|
|
|
opt_recv = &hctx->ccid3hctx_options_received;
|
|
|
|
switch (hctx->ccid3hctx_state) {
|
|
case TFRC_SSTATE_NO_FBACK:
|
|
case TFRC_SSTATE_FBACK:
|
|
/* get packet from history to look up t_recvdata */
|
|
packet = dccp_tx_hist_find_entry(&hctx->ccid3hctx_hist,
|
|
DCCP_SKB_CB(skb)->dccpd_ack_seq);
|
|
if (unlikely(packet == NULL)) {
|
|
DCCP_WARN("%s(%p), seqno %llu(%s) doesn't exist "
|
|
"in history!\n", dccp_role(sk), sk,
|
|
(unsigned long long)DCCP_SKB_CB(skb)->dccpd_ack_seq,
|
|
dccp_packet_name(DCCP_SKB_CB(skb)->dccpd_type));
|
|
return;
|
|
}
|
|
|
|
/* Update receive rate in units of 64 * bytes/second */
|
|
hctx->ccid3hctx_x_recv = opt_recv->ccid3or_receive_rate;
|
|
hctx->ccid3hctx_x_recv <<= 6;
|
|
|
|
/* Update loss event rate */
|
|
pinv = opt_recv->ccid3or_loss_event_rate;
|
|
if (pinv == ~0U || pinv == 0) /* see RFC 4342, 8.5 */
|
|
hctx->ccid3hctx_p = 0;
|
|
else /* can not exceed 100% */
|
|
hctx->ccid3hctx_p = 1000000 / pinv;
|
|
|
|
dccp_timestamp(sk, &now);
|
|
|
|
/*
|
|
* Calculate new round trip sample as per [RFC 3448, 4.3] by
|
|
* R_sample = (now - t_recvdata) - t_elapsed
|
|
*/
|
|
r_sample = dccp_sample_rtt(sk, &now, &packet->dccphtx_tstamp);
|
|
|
|
/*
|
|
* Update RTT estimate by
|
|
* If (No feedback recv)
|
|
* R = R_sample;
|
|
* Else
|
|
* R = q * R + (1 - q) * R_sample;
|
|
*
|
|
* q is a constant, RFC 3448 recomments 0.9
|
|
*/
|
|
if (hctx->ccid3hctx_state == TFRC_SSTATE_NO_FBACK) {
|
|
/*
|
|
* Larger Initial Windows [RFC 4342, sec. 5]
|
|
*/
|
|
hctx->ccid3hctx_rtt = r_sample;
|
|
hctx->ccid3hctx_x = rfc3390_initial_rate(sk);
|
|
hctx->ccid3hctx_t_ld = now;
|
|
|
|
ccid3_update_send_interval(hctx);
|
|
|
|
ccid3_pr_debug("%s(%p), s=%u, MSS=%u, "
|
|
"R_sample=%uus, X=%u\n", dccp_role(sk),
|
|
sk, hctx->ccid3hctx_s,
|
|
dccp_sk(sk)->dccps_mss_cache, r_sample,
|
|
(unsigned)(hctx->ccid3hctx_x >> 6));
|
|
|
|
ccid3_hc_tx_set_state(sk, TFRC_SSTATE_FBACK);
|
|
} else {
|
|
hctx->ccid3hctx_rtt = (9 * hctx->ccid3hctx_rtt +
|
|
r_sample) / 10;
|
|
|
|
/* Update sending rate (step 4 of [RFC 3448, 4.3]) */
|
|
if (hctx->ccid3hctx_p > 0)
|
|
hctx->ccid3hctx_x_calc =
|
|
tfrc_calc_x(hctx->ccid3hctx_s,
|
|
hctx->ccid3hctx_rtt,
|
|
hctx->ccid3hctx_p);
|
|
ccid3_hc_tx_update_x(sk, &now);
|
|
|
|
ccid3_pr_debug("%s(%p), RTT=%uus (sample=%uus), s=%u, "
|
|
"p=%u, X_calc=%u, X_recv=%u, X=%u\n",
|
|
dccp_role(sk),
|
|
sk, hctx->ccid3hctx_rtt, r_sample,
|
|
hctx->ccid3hctx_s, hctx->ccid3hctx_p,
|
|
hctx->ccid3hctx_x_calc,
|
|
(unsigned)(hctx->ccid3hctx_x_recv >> 6),
|
|
(unsigned)(hctx->ccid3hctx_x >> 6));
|
|
}
|
|
|
|
/* unschedule no feedback timer */
|
|
sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
|
|
|
|
/* remove all packets older than the one acked from history */
|
|
dccp_tx_hist_purge_older(ccid3_tx_hist,
|
|
&hctx->ccid3hctx_hist, packet);
|
|
/*
|
|
* As we have calculated new ipi, delta, t_nom it is possible
|
|
* that we now can send a packet, so wake up dccp_wait_for_ccid
|
|
*/
|
|
sk->sk_write_space(sk);
|
|
|
|
/*
|
|
* Update timeout interval for the nofeedback timer.
|
|
* We use a configuration option to increase the lower bound.
|
|
* This can help avoid triggering the nofeedback timer too
|
|
* often ('spinning') on LANs with small RTTs.
|
|
*/
|
|
hctx->ccid3hctx_t_rto = max_t(u32, 4 * hctx->ccid3hctx_rtt,
|
|
CONFIG_IP_DCCP_CCID3_RTO *
|
|
(USEC_PER_SEC/1000));
|
|
/*
|
|
* Schedule no feedback timer to expire in
|
|
* max(t_RTO, 2 * s/X) = max(t_RTO, 2 * t_ipi)
|
|
*/
|
|
t_nfb = max(hctx->ccid3hctx_t_rto, 2 * hctx->ccid3hctx_t_ipi);
|
|
|
|
ccid3_pr_debug("%s(%p), Scheduled no feedback timer to "
|
|
"expire in %lu jiffies (%luus)\n",
|
|
dccp_role(sk),
|
|
sk, usecs_to_jiffies(t_nfb), t_nfb);
|
|
|
|
sk_reset_timer(sk, &hctx->ccid3hctx_no_feedback_timer,
|
|
jiffies + usecs_to_jiffies(t_nfb));
|
|
|
|
/* set idle flag */
|
|
hctx->ccid3hctx_idle = 1;
|
|
break;
|
|
case TFRC_SSTATE_NO_SENT: /* fall through */
|
|
case TFRC_SSTATE_TERM: /* ignore feedback when closing */
|
|
break;
|
|
}
|
|
}
|
|
|
|
static int ccid3_hc_tx_parse_options(struct sock *sk, unsigned char option,
|
|
unsigned char len, u16 idx,
|
|
unsigned char *value)
|
|
{
|
|
int rc = 0;
|
|
const struct dccp_sock *dp = dccp_sk(sk);
|
|
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
|
|
struct ccid3_options_received *opt_recv;
|
|
|
|
BUG_ON(hctx == NULL);
|
|
|
|
opt_recv = &hctx->ccid3hctx_options_received;
|
|
|
|
if (opt_recv->ccid3or_seqno != dp->dccps_gsr) {
|
|
opt_recv->ccid3or_seqno = dp->dccps_gsr;
|
|
opt_recv->ccid3or_loss_event_rate = ~0;
|
|
opt_recv->ccid3or_loss_intervals_idx = 0;
|
|
opt_recv->ccid3or_loss_intervals_len = 0;
|
|
opt_recv->ccid3or_receive_rate = 0;
|
|
}
|
|
|
|
switch (option) {
|
|
case TFRC_OPT_LOSS_EVENT_RATE:
|
|
if (unlikely(len != 4)) {
|
|
DCCP_WARN("%s(%p), invalid len %d "
|
|
"for TFRC_OPT_LOSS_EVENT_RATE\n",
|
|
dccp_role(sk), sk, len);
|
|
rc = -EINVAL;
|
|
} else {
|
|
opt_recv->ccid3or_loss_event_rate =
|
|
ntohl(*(__be32 *)value);
|
|
ccid3_pr_debug("%s(%p), LOSS_EVENT_RATE=%u\n",
|
|
dccp_role(sk), sk,
|
|
opt_recv->ccid3or_loss_event_rate);
|
|
}
|
|
break;
|
|
case TFRC_OPT_LOSS_INTERVALS:
|
|
opt_recv->ccid3or_loss_intervals_idx = idx;
|
|
opt_recv->ccid3or_loss_intervals_len = len;
|
|
ccid3_pr_debug("%s(%p), LOSS_INTERVALS=(%u, %u)\n",
|
|
dccp_role(sk), sk,
|
|
opt_recv->ccid3or_loss_intervals_idx,
|
|
opt_recv->ccid3or_loss_intervals_len);
|
|
break;
|
|
case TFRC_OPT_RECEIVE_RATE:
|
|
if (unlikely(len != 4)) {
|
|
DCCP_WARN("%s(%p), invalid len %d "
|
|
"for TFRC_OPT_RECEIVE_RATE\n",
|
|
dccp_role(sk), sk, len);
|
|
rc = -EINVAL;
|
|
} else {
|
|
opt_recv->ccid3or_receive_rate =
|
|
ntohl(*(__be32 *)value);
|
|
ccid3_pr_debug("%s(%p), RECEIVE_RATE=%u\n",
|
|
dccp_role(sk), sk,
|
|
opt_recv->ccid3or_receive_rate);
|
|
}
|
|
break;
|
|
}
|
|
|
|
return rc;
|
|
}
|
|
|
|
static int ccid3_hc_tx_init(struct ccid *ccid, struct sock *sk)
|
|
{
|
|
struct ccid3_hc_tx_sock *hctx = ccid_priv(ccid);
|
|
|
|
hctx->ccid3hctx_s = 0;
|
|
hctx->ccid3hctx_rtt = 0;
|
|
hctx->ccid3hctx_state = TFRC_SSTATE_NO_SENT;
|
|
INIT_LIST_HEAD(&hctx->ccid3hctx_hist);
|
|
|
|
hctx->ccid3hctx_no_feedback_timer.function =
|
|
ccid3_hc_tx_no_feedback_timer;
|
|
hctx->ccid3hctx_no_feedback_timer.data = (unsigned long)sk;
|
|
init_timer(&hctx->ccid3hctx_no_feedback_timer);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ccid3_hc_tx_exit(struct sock *sk)
|
|
{
|
|
struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
|
|
|
|
BUG_ON(hctx == NULL);
|
|
|
|
ccid3_hc_tx_set_state(sk, TFRC_SSTATE_TERM);
|
|
sk_stop_timer(sk, &hctx->ccid3hctx_no_feedback_timer);
|
|
|
|
/* Empty packet history */
|
|
dccp_tx_hist_purge(ccid3_tx_hist, &hctx->ccid3hctx_hist);
|
|
}
|
|
|
|
static void ccid3_hc_tx_get_info(struct sock *sk, struct tcp_info *info)
|
|
{
|
|
const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
|
|
|
|
/* Listen socks doesn't have a private CCID block */
|
|
if (sk->sk_state == DCCP_LISTEN)
|
|
return;
|
|
|
|
BUG_ON(hctx == NULL);
|
|
|
|
info->tcpi_rto = hctx->ccid3hctx_t_rto;
|
|
info->tcpi_rtt = hctx->ccid3hctx_rtt;
|
|
}
|
|
|
|
static int ccid3_hc_tx_getsockopt(struct sock *sk, const int optname, int len,
|
|
u32 __user *optval, int __user *optlen)
|
|
{
|
|
const struct ccid3_hc_tx_sock *hctx = ccid3_hc_tx_sk(sk);
|
|
const void *val;
|
|
|
|
/* Listen socks doesn't have a private CCID block */
|
|
if (sk->sk_state == DCCP_LISTEN)
|
|
return -EINVAL;
|
|
|
|
switch (optname) {
|
|
case DCCP_SOCKOPT_CCID_TX_INFO:
|
|
if (len < sizeof(hctx->ccid3hctx_tfrc))
|
|
return -EINVAL;
|
|
len = sizeof(hctx->ccid3hctx_tfrc);
|
|
val = &hctx->ccid3hctx_tfrc;
|
|
break;
|
|
default:
|
|
return -ENOPROTOOPT;
|
|
}
|
|
|
|
if (put_user(len, optlen) || copy_to_user(optval, val, len))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Receiver Half-Connection Routines
|
|
*/
|
|
#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
|
|
static const char *ccid3_rx_state_name(enum ccid3_hc_rx_states state)
|
|
{
|
|
static char *ccid3_rx_state_names[] = {
|
|
[TFRC_RSTATE_NO_DATA] = "NO_DATA",
|
|
[TFRC_RSTATE_DATA] = "DATA",
|
|
[TFRC_RSTATE_TERM] = "TERM",
|
|
};
|
|
|
|
return ccid3_rx_state_names[state];
|
|
}
|
|
#endif
|
|
|
|
static void ccid3_hc_rx_set_state(struct sock *sk,
|
|
enum ccid3_hc_rx_states state)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
enum ccid3_hc_rx_states oldstate = hcrx->ccid3hcrx_state;
|
|
|
|
ccid3_pr_debug("%s(%p) %-8.8s -> %s\n",
|
|
dccp_role(sk), sk, ccid3_rx_state_name(oldstate),
|
|
ccid3_rx_state_name(state));
|
|
WARN_ON(state == oldstate);
|
|
hcrx->ccid3hcrx_state = state;
|
|
}
|
|
|
|
static inline void ccid3_hc_rx_update_s(struct ccid3_hc_rx_sock *hcrx, int len)
|
|
{
|
|
if (unlikely(len == 0)) /* don't update on empty packets (e.g. ACKs) */
|
|
ccid3_pr_debug("Packet payload length is 0 - not updating\n");
|
|
else
|
|
hcrx->ccid3hcrx_s = hcrx->ccid3hcrx_s == 0 ? len :
|
|
(9 * hcrx->ccid3hcrx_s + len) / 10;
|
|
}
|
|
|
|
static void ccid3_hc_rx_send_feedback(struct sock *sk)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
struct dccp_sock *dp = dccp_sk(sk);
|
|
struct dccp_rx_hist_entry *packet;
|
|
struct timeval now;
|
|
suseconds_t delta;
|
|
|
|
ccid3_pr_debug("%s(%p) - entry \n", dccp_role(sk), sk);
|
|
|
|
dccp_timestamp(sk, &now);
|
|
|
|
switch (hcrx->ccid3hcrx_state) {
|
|
case TFRC_RSTATE_NO_DATA:
|
|
hcrx->ccid3hcrx_x_recv = 0;
|
|
break;
|
|
case TFRC_RSTATE_DATA:
|
|
delta = timeval_delta(&now,
|
|
&hcrx->ccid3hcrx_tstamp_last_feedback);
|
|
DCCP_BUG_ON(delta < 0);
|
|
hcrx->ccid3hcrx_x_recv =
|
|
scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
|
|
break;
|
|
case TFRC_RSTATE_TERM:
|
|
DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
|
|
return;
|
|
}
|
|
|
|
packet = dccp_rx_hist_find_data_packet(&hcrx->ccid3hcrx_hist);
|
|
if (unlikely(packet == NULL)) {
|
|
DCCP_WARN("%s(%p), no data packet in history!\n",
|
|
dccp_role(sk), sk);
|
|
return;
|
|
}
|
|
|
|
hcrx->ccid3hcrx_tstamp_last_feedback = now;
|
|
hcrx->ccid3hcrx_ccval_last_counter = packet->dccphrx_ccval;
|
|
hcrx->ccid3hcrx_bytes_recv = 0;
|
|
|
|
/* Elapsed time information [RFC 4340, 13.2] in units of 10 * usecs */
|
|
delta = timeval_delta(&now, &packet->dccphrx_tstamp);
|
|
DCCP_BUG_ON(delta < 0);
|
|
hcrx->ccid3hcrx_elapsed_time = delta / 10;
|
|
|
|
if (hcrx->ccid3hcrx_p == 0)
|
|
hcrx->ccid3hcrx_pinv = ~0U; /* see RFC 4342, 8.5 */
|
|
else if (hcrx->ccid3hcrx_p > 1000000) {
|
|
DCCP_WARN("p (%u) > 100%%\n", hcrx->ccid3hcrx_p);
|
|
hcrx->ccid3hcrx_pinv = 1; /* use 100% in this case */
|
|
} else
|
|
hcrx->ccid3hcrx_pinv = 1000000 / hcrx->ccid3hcrx_p;
|
|
|
|
dp->dccps_hc_rx_insert_options = 1;
|
|
dccp_send_ack(sk);
|
|
}
|
|
|
|
static int ccid3_hc_rx_insert_options(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
__be32 x_recv, pinv;
|
|
|
|
BUG_ON(hcrx == NULL);
|
|
|
|
if (!(sk->sk_state == DCCP_OPEN || sk->sk_state == DCCP_PARTOPEN))
|
|
return 0;
|
|
|
|
DCCP_SKB_CB(skb)->dccpd_ccval = hcrx->ccid3hcrx_ccval_last_counter;
|
|
|
|
if (dccp_packet_without_ack(skb))
|
|
return 0;
|
|
|
|
x_recv = htonl(hcrx->ccid3hcrx_x_recv);
|
|
pinv = htonl(hcrx->ccid3hcrx_pinv);
|
|
|
|
if ((hcrx->ccid3hcrx_elapsed_time != 0 &&
|
|
dccp_insert_option_elapsed_time(sk, skb,
|
|
hcrx->ccid3hcrx_elapsed_time)) ||
|
|
dccp_insert_option_timestamp(sk, skb) ||
|
|
dccp_insert_option(sk, skb, TFRC_OPT_LOSS_EVENT_RATE,
|
|
&pinv, sizeof(pinv)) ||
|
|
dccp_insert_option(sk, skb, TFRC_OPT_RECEIVE_RATE,
|
|
&x_recv, sizeof(x_recv)))
|
|
return -1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* calculate first loss interval
|
|
*
|
|
* returns estimated loss interval in usecs */
|
|
|
|
static u32 ccid3_hc_rx_calc_first_li(struct sock *sk)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
struct dccp_rx_hist_entry *entry, *next, *tail = NULL;
|
|
u32 x_recv, p;
|
|
suseconds_t rtt, delta;
|
|
struct timeval tstamp = { 0, };
|
|
int interval = 0;
|
|
int win_count = 0;
|
|
int step = 0;
|
|
u64 fval;
|
|
|
|
list_for_each_entry_safe(entry, next, &hcrx->ccid3hcrx_hist,
|
|
dccphrx_node) {
|
|
if (dccp_rx_hist_entry_data_packet(entry)) {
|
|
tail = entry;
|
|
|
|
switch (step) {
|
|
case 0:
|
|
tstamp = entry->dccphrx_tstamp;
|
|
win_count = entry->dccphrx_ccval;
|
|
step = 1;
|
|
break;
|
|
case 1:
|
|
interval = win_count - entry->dccphrx_ccval;
|
|
if (interval < 0)
|
|
interval += TFRC_WIN_COUNT_LIMIT;
|
|
if (interval > 4)
|
|
goto found;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (unlikely(step == 0)) {
|
|
DCCP_WARN("%s(%p), packet history has no data packets!\n",
|
|
dccp_role(sk), sk);
|
|
return ~0;
|
|
}
|
|
|
|
if (unlikely(interval == 0)) {
|
|
DCCP_WARN("%s(%p), Could not find a win_count interval > 0."
|
|
"Defaulting to 1\n", dccp_role(sk), sk);
|
|
interval = 1;
|
|
}
|
|
found:
|
|
if (!tail) {
|
|
DCCP_CRIT("tail is null\n");
|
|
return ~0;
|
|
}
|
|
|
|
delta = timeval_delta(&tstamp, &tail->dccphrx_tstamp);
|
|
DCCP_BUG_ON(delta < 0);
|
|
|
|
rtt = delta * 4 / interval;
|
|
ccid3_pr_debug("%s(%p), approximated RTT to %dus\n",
|
|
dccp_role(sk), sk, (int)rtt);
|
|
|
|
/*
|
|
* Determine the length of the first loss interval via inverse lookup.
|
|
* Assume that X_recv can be computed by the throughput equation
|
|
* s
|
|
* X_recv = --------
|
|
* R * fval
|
|
* Find some p such that f(p) = fval; return 1/p [RFC 3448, 6.3.1].
|
|
*/
|
|
if (rtt == 0) { /* would result in divide-by-zero */
|
|
DCCP_WARN("RTT==0\n");
|
|
return ~0;
|
|
}
|
|
|
|
dccp_timestamp(sk, &tstamp);
|
|
delta = timeval_delta(&tstamp, &hcrx->ccid3hcrx_tstamp_last_feedback);
|
|
DCCP_BUG_ON(delta <= 0);
|
|
|
|
x_recv = scaled_div32(hcrx->ccid3hcrx_bytes_recv, delta);
|
|
if (x_recv == 0) { /* would also trigger divide-by-zero */
|
|
DCCP_WARN("X_recv==0\n");
|
|
if ((x_recv = hcrx->ccid3hcrx_x_recv) == 0) {
|
|
DCCP_BUG("stored value of X_recv is zero");
|
|
return ~0;
|
|
}
|
|
}
|
|
|
|
fval = scaled_div(hcrx->ccid3hcrx_s, rtt);
|
|
fval = scaled_div32(fval, x_recv);
|
|
p = tfrc_calc_x_reverse_lookup(fval);
|
|
|
|
ccid3_pr_debug("%s(%p), receive rate=%u bytes/s, implied "
|
|
"loss rate=%u\n", dccp_role(sk), sk, x_recv, p);
|
|
|
|
if (p == 0)
|
|
return ~0;
|
|
else
|
|
return 1000000 / p;
|
|
}
|
|
|
|
static void ccid3_hc_rx_update_li(struct sock *sk, u64 seq_loss, u8 win_loss)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
struct dccp_li_hist_entry *head;
|
|
u64 seq_temp;
|
|
|
|
if (list_empty(&hcrx->ccid3hcrx_li_hist)) {
|
|
if (!dccp_li_hist_interval_new(ccid3_li_hist,
|
|
&hcrx->ccid3hcrx_li_hist, seq_loss, win_loss))
|
|
return;
|
|
|
|
head = list_entry(hcrx->ccid3hcrx_li_hist.next,
|
|
struct dccp_li_hist_entry, dccplih_node);
|
|
head->dccplih_interval = ccid3_hc_rx_calc_first_li(sk);
|
|
} else {
|
|
struct dccp_li_hist_entry *entry;
|
|
struct list_head *tail;
|
|
|
|
head = list_entry(hcrx->ccid3hcrx_li_hist.next,
|
|
struct dccp_li_hist_entry, dccplih_node);
|
|
/* FIXME win count check removed as was wrong */
|
|
/* should make this check with receive history */
|
|
/* and compare there as per section 10.2 of RFC4342 */
|
|
|
|
/* new loss event detected */
|
|
/* calculate last interval length */
|
|
seq_temp = dccp_delta_seqno(head->dccplih_seqno, seq_loss);
|
|
entry = dccp_li_hist_entry_new(ccid3_li_hist, GFP_ATOMIC);
|
|
|
|
if (entry == NULL) {
|
|
DCCP_BUG("out of memory - can not allocate entry");
|
|
return;
|
|
}
|
|
|
|
list_add(&entry->dccplih_node, &hcrx->ccid3hcrx_li_hist);
|
|
|
|
tail = hcrx->ccid3hcrx_li_hist.prev;
|
|
list_del(tail);
|
|
kmem_cache_free(ccid3_li_hist->dccplih_slab, tail);
|
|
|
|
/* Create the newest interval */
|
|
entry->dccplih_seqno = seq_loss;
|
|
entry->dccplih_interval = seq_temp;
|
|
entry->dccplih_win_count = win_loss;
|
|
}
|
|
}
|
|
|
|
static int ccid3_hc_rx_detect_loss(struct sock *sk,
|
|
struct dccp_rx_hist_entry *packet)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
struct dccp_rx_hist_entry *rx_hist =
|
|
dccp_rx_hist_head(&hcrx->ccid3hcrx_hist);
|
|
u64 seqno = packet->dccphrx_seqno;
|
|
u64 tmp_seqno;
|
|
int loss = 0;
|
|
u8 ccval;
|
|
|
|
|
|
tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
|
|
|
|
if (!rx_hist ||
|
|
follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) {
|
|
hcrx->ccid3hcrx_seqno_nonloss = seqno;
|
|
hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval;
|
|
goto detect_out;
|
|
}
|
|
|
|
|
|
while (dccp_delta_seqno(hcrx->ccid3hcrx_seqno_nonloss, seqno)
|
|
> TFRC_RECV_NUM_LATE_LOSS) {
|
|
loss = 1;
|
|
ccid3_hc_rx_update_li(sk, hcrx->ccid3hcrx_seqno_nonloss,
|
|
hcrx->ccid3hcrx_ccval_nonloss);
|
|
tmp_seqno = hcrx->ccid3hcrx_seqno_nonloss;
|
|
dccp_inc_seqno(&tmp_seqno);
|
|
hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
|
|
dccp_inc_seqno(&tmp_seqno);
|
|
while (dccp_rx_hist_find_entry(&hcrx->ccid3hcrx_hist,
|
|
tmp_seqno, &ccval)) {
|
|
hcrx->ccid3hcrx_seqno_nonloss = tmp_seqno;
|
|
hcrx->ccid3hcrx_ccval_nonloss = ccval;
|
|
dccp_inc_seqno(&tmp_seqno);
|
|
}
|
|
}
|
|
|
|
/* FIXME - this code could be simplified with above while */
|
|
/* but works at moment */
|
|
if (follows48(packet->dccphrx_seqno, hcrx->ccid3hcrx_seqno_nonloss)) {
|
|
hcrx->ccid3hcrx_seqno_nonloss = seqno;
|
|
hcrx->ccid3hcrx_ccval_nonloss = packet->dccphrx_ccval;
|
|
}
|
|
|
|
detect_out:
|
|
dccp_rx_hist_add_packet(ccid3_rx_hist, &hcrx->ccid3hcrx_hist,
|
|
&hcrx->ccid3hcrx_li_hist, packet,
|
|
hcrx->ccid3hcrx_seqno_nonloss);
|
|
return loss;
|
|
}
|
|
|
|
static void ccid3_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
const struct dccp_options_received *opt_recv;
|
|
struct dccp_rx_hist_entry *packet;
|
|
struct timeval now;
|
|
u32 p_prev, r_sample, rtt_prev;
|
|
int loss, payload_size;
|
|
|
|
BUG_ON(hcrx == NULL);
|
|
|
|
opt_recv = &dccp_sk(sk)->dccps_options_received;
|
|
|
|
switch (DCCP_SKB_CB(skb)->dccpd_type) {
|
|
case DCCP_PKT_ACK:
|
|
if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
|
|
return;
|
|
case DCCP_PKT_DATAACK:
|
|
if (opt_recv->dccpor_timestamp_echo == 0)
|
|
break;
|
|
rtt_prev = hcrx->ccid3hcrx_rtt;
|
|
dccp_timestamp(sk, &now);
|
|
r_sample = dccp_sample_rtt(sk, &now, NULL);
|
|
|
|
if (hcrx->ccid3hcrx_state == TFRC_RSTATE_NO_DATA)
|
|
hcrx->ccid3hcrx_rtt = r_sample;
|
|
else
|
|
hcrx->ccid3hcrx_rtt = (hcrx->ccid3hcrx_rtt * 9) / 10 +
|
|
r_sample / 10;
|
|
|
|
if (rtt_prev != hcrx->ccid3hcrx_rtt)
|
|
ccid3_pr_debug("%s(%p), New RTT=%uus, elapsed time=%u\n",
|
|
dccp_role(sk), sk, hcrx->ccid3hcrx_rtt,
|
|
opt_recv->dccpor_elapsed_time);
|
|
break;
|
|
case DCCP_PKT_DATA:
|
|
break;
|
|
default: /* We're not interested in other packet types, move along */
|
|
return;
|
|
}
|
|
|
|
packet = dccp_rx_hist_entry_new(ccid3_rx_hist, sk, opt_recv->dccpor_ndp,
|
|
skb, GFP_ATOMIC);
|
|
if (unlikely(packet == NULL)) {
|
|
DCCP_WARN("%s(%p), Not enough mem to add rx packet "
|
|
"to history, consider it lost!\n", dccp_role(sk), sk);
|
|
return;
|
|
}
|
|
|
|
loss = ccid3_hc_rx_detect_loss(sk, packet);
|
|
|
|
if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_ACK)
|
|
return;
|
|
|
|
payload_size = skb->len - dccp_hdr(skb)->dccph_doff * 4;
|
|
ccid3_hc_rx_update_s(hcrx, payload_size);
|
|
|
|
switch (hcrx->ccid3hcrx_state) {
|
|
case TFRC_RSTATE_NO_DATA:
|
|
ccid3_pr_debug("%s(%p, state=%s), skb=%p, sending initial "
|
|
"feedback\n", dccp_role(sk), sk,
|
|
dccp_state_name(sk->sk_state), skb);
|
|
ccid3_hc_rx_send_feedback(sk);
|
|
ccid3_hc_rx_set_state(sk, TFRC_RSTATE_DATA);
|
|
return;
|
|
case TFRC_RSTATE_DATA:
|
|
hcrx->ccid3hcrx_bytes_recv += payload_size;
|
|
if (loss)
|
|
break;
|
|
|
|
dccp_timestamp(sk, &now);
|
|
if ((timeval_delta(&now, &hcrx->ccid3hcrx_tstamp_last_ack) -
|
|
(suseconds_t)hcrx->ccid3hcrx_rtt) >= 0) {
|
|
hcrx->ccid3hcrx_tstamp_last_ack = now;
|
|
ccid3_hc_rx_send_feedback(sk);
|
|
}
|
|
return;
|
|
case TFRC_RSTATE_TERM:
|
|
DCCP_BUG("%s(%p) - Illegal state TERM", dccp_role(sk), sk);
|
|
return;
|
|
}
|
|
|
|
/* Dealing with packet loss */
|
|
ccid3_pr_debug("%s(%p, state=%s), data loss! Reacting...\n",
|
|
dccp_role(sk), sk, dccp_state_name(sk->sk_state));
|
|
|
|
p_prev = hcrx->ccid3hcrx_p;
|
|
|
|
/* Calculate loss event rate */
|
|
if (!list_empty(&hcrx->ccid3hcrx_li_hist)) {
|
|
u32 i_mean = dccp_li_hist_calc_i_mean(&hcrx->ccid3hcrx_li_hist);
|
|
|
|
/* Scaling up by 1000000 as fixed decimal */
|
|
if (i_mean != 0)
|
|
hcrx->ccid3hcrx_p = 1000000 / i_mean;
|
|
} else
|
|
DCCP_BUG("empty loss history");
|
|
|
|
if (hcrx->ccid3hcrx_p > p_prev) {
|
|
ccid3_hc_rx_send_feedback(sk);
|
|
return;
|
|
}
|
|
}
|
|
|
|
static int ccid3_hc_rx_init(struct ccid *ccid, struct sock *sk)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid_priv(ccid);
|
|
|
|
ccid3_pr_debug("entry\n");
|
|
|
|
hcrx->ccid3hcrx_state = TFRC_RSTATE_NO_DATA;
|
|
INIT_LIST_HEAD(&hcrx->ccid3hcrx_hist);
|
|
INIT_LIST_HEAD(&hcrx->ccid3hcrx_li_hist);
|
|
dccp_timestamp(sk, &hcrx->ccid3hcrx_tstamp_last_ack);
|
|
hcrx->ccid3hcrx_tstamp_last_feedback = hcrx->ccid3hcrx_tstamp_last_ack;
|
|
hcrx->ccid3hcrx_s = 0;
|
|
hcrx->ccid3hcrx_rtt = 0;
|
|
return 0;
|
|
}
|
|
|
|
static void ccid3_hc_rx_exit(struct sock *sk)
|
|
{
|
|
struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
|
|
BUG_ON(hcrx == NULL);
|
|
|
|
ccid3_hc_rx_set_state(sk, TFRC_RSTATE_TERM);
|
|
|
|
/* Empty packet history */
|
|
dccp_rx_hist_purge(ccid3_rx_hist, &hcrx->ccid3hcrx_hist);
|
|
|
|
/* Empty loss interval history */
|
|
dccp_li_hist_purge(ccid3_li_hist, &hcrx->ccid3hcrx_li_hist);
|
|
}
|
|
|
|
static void ccid3_hc_rx_get_info(struct sock *sk, struct tcp_info *info)
|
|
{
|
|
const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
|
|
/* Listen socks doesn't have a private CCID block */
|
|
if (sk->sk_state == DCCP_LISTEN)
|
|
return;
|
|
|
|
BUG_ON(hcrx == NULL);
|
|
|
|
info->tcpi_ca_state = hcrx->ccid3hcrx_state;
|
|
info->tcpi_options |= TCPI_OPT_TIMESTAMPS;
|
|
info->tcpi_rcv_rtt = hcrx->ccid3hcrx_rtt;
|
|
}
|
|
|
|
static int ccid3_hc_rx_getsockopt(struct sock *sk, const int optname, int len,
|
|
u32 __user *optval, int __user *optlen)
|
|
{
|
|
const struct ccid3_hc_rx_sock *hcrx = ccid3_hc_rx_sk(sk);
|
|
const void *val;
|
|
|
|
/* Listen socks doesn't have a private CCID block */
|
|
if (sk->sk_state == DCCP_LISTEN)
|
|
return -EINVAL;
|
|
|
|
switch (optname) {
|
|
case DCCP_SOCKOPT_CCID_RX_INFO:
|
|
if (len < sizeof(hcrx->ccid3hcrx_tfrc))
|
|
return -EINVAL;
|
|
len = sizeof(hcrx->ccid3hcrx_tfrc);
|
|
val = &hcrx->ccid3hcrx_tfrc;
|
|
break;
|
|
default:
|
|
return -ENOPROTOOPT;
|
|
}
|
|
|
|
if (put_user(len, optlen) || copy_to_user(optval, val, len))
|
|
return -EFAULT;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct ccid_operations ccid3 = {
|
|
.ccid_id = DCCPC_CCID3,
|
|
.ccid_name = "ccid3",
|
|
.ccid_owner = THIS_MODULE,
|
|
.ccid_hc_tx_obj_size = sizeof(struct ccid3_hc_tx_sock),
|
|
.ccid_hc_tx_init = ccid3_hc_tx_init,
|
|
.ccid_hc_tx_exit = ccid3_hc_tx_exit,
|
|
.ccid_hc_tx_send_packet = ccid3_hc_tx_send_packet,
|
|
.ccid_hc_tx_packet_sent = ccid3_hc_tx_packet_sent,
|
|
.ccid_hc_tx_packet_recv = ccid3_hc_tx_packet_recv,
|
|
.ccid_hc_tx_parse_options = ccid3_hc_tx_parse_options,
|
|
.ccid_hc_rx_obj_size = sizeof(struct ccid3_hc_rx_sock),
|
|
.ccid_hc_rx_init = ccid3_hc_rx_init,
|
|
.ccid_hc_rx_exit = ccid3_hc_rx_exit,
|
|
.ccid_hc_rx_insert_options = ccid3_hc_rx_insert_options,
|
|
.ccid_hc_rx_packet_recv = ccid3_hc_rx_packet_recv,
|
|
.ccid_hc_rx_get_info = ccid3_hc_rx_get_info,
|
|
.ccid_hc_tx_get_info = ccid3_hc_tx_get_info,
|
|
.ccid_hc_rx_getsockopt = ccid3_hc_rx_getsockopt,
|
|
.ccid_hc_tx_getsockopt = ccid3_hc_tx_getsockopt,
|
|
};
|
|
|
|
#ifdef CONFIG_IP_DCCP_CCID3_DEBUG
|
|
module_param(ccid3_debug, int, 0444);
|
|
MODULE_PARM_DESC(ccid3_debug, "Enable debug messages");
|
|
#endif
|
|
|
|
static __init int ccid3_module_init(void)
|
|
{
|
|
int rc = -ENOBUFS;
|
|
|
|
ccid3_rx_hist = dccp_rx_hist_new("ccid3");
|
|
if (ccid3_rx_hist == NULL)
|
|
goto out;
|
|
|
|
ccid3_tx_hist = dccp_tx_hist_new("ccid3");
|
|
if (ccid3_tx_hist == NULL)
|
|
goto out_free_rx;
|
|
|
|
ccid3_li_hist = dccp_li_hist_new("ccid3");
|
|
if (ccid3_li_hist == NULL)
|
|
goto out_free_tx;
|
|
|
|
rc = ccid_register(&ccid3);
|
|
if (rc != 0)
|
|
goto out_free_loss_interval_history;
|
|
out:
|
|
return rc;
|
|
|
|
out_free_loss_interval_history:
|
|
dccp_li_hist_delete(ccid3_li_hist);
|
|
ccid3_li_hist = NULL;
|
|
out_free_tx:
|
|
dccp_tx_hist_delete(ccid3_tx_hist);
|
|
ccid3_tx_hist = NULL;
|
|
out_free_rx:
|
|
dccp_rx_hist_delete(ccid3_rx_hist);
|
|
ccid3_rx_hist = NULL;
|
|
goto out;
|
|
}
|
|
module_init(ccid3_module_init);
|
|
|
|
static __exit void ccid3_module_exit(void)
|
|
{
|
|
ccid_unregister(&ccid3);
|
|
|
|
if (ccid3_tx_hist != NULL) {
|
|
dccp_tx_hist_delete(ccid3_tx_hist);
|
|
ccid3_tx_hist = NULL;
|
|
}
|
|
if (ccid3_rx_hist != NULL) {
|
|
dccp_rx_hist_delete(ccid3_rx_hist);
|
|
ccid3_rx_hist = NULL;
|
|
}
|
|
if (ccid3_li_hist != NULL) {
|
|
dccp_li_hist_delete(ccid3_li_hist);
|
|
ccid3_li_hist = NULL;
|
|
}
|
|
}
|
|
module_exit(ccid3_module_exit);
|
|
|
|
MODULE_AUTHOR("Ian McDonald <ian.mcdonald@jandi.co.nz>, "
|
|
"Arnaldo Carvalho de Melo <acme@ghostprotocols.net>");
|
|
MODULE_DESCRIPTION("DCCP TFRC CCID3 CCID");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("net-dccp-ccid-3");
|