From 2a91aa3967398fb94eccc8da67c82bce9f67afdf Mon Sep 17 00:00:00 2001 From: Andrea Bittau Date: Mon, 20 Mar 2006 17:41:47 -0800 Subject: [DCCP] CCID2: Initial CCID2 (TCP-Like) implementation Original work by Andrea Bittau, Arnaldo Melo cleaned up and fixed several issues on the merge process. For now CCID2 was turned the default for all SOCK_DCCP connections, but this will be remedied soon with the merge of the feature negotiation code. Signed-off-by: Andrea Bittau Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/dccp/ccids/ccid2.c | 838 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 838 insertions(+) create mode 100644 net/dccp/ccids/ccid2.c (limited to 'net/dccp/ccids/ccid2.c') diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c new file mode 100644 index 000000000000..4a7b87512560 --- /dev/null +++ b/net/dccp/ccids/ccid2.c @@ -0,0 +1,838 @@ +/* + * net/dccp/ccids/ccid2.c + * + * Copyright (c) 2005, 2006 Andrea Bittau + * + * Changes to meet Linux coding standards, and DCCP infrastructure fixes. + * + * Copyright (c) 2006 Arnaldo Carvalho de Melo + * + * This program 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 of the License, or + * (at your option) any later version. + * + * This program 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 this program; if not, write to the Free Software + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + */ + +/* + * This implementation should follow: draft-ietf-dccp-ccid2-10.txt + * + * BUGS: + * - sequence number wrapping + * - jiffies wrapping + */ + +#include +#include "../ccid.h" +#include "../dccp.h" +#include "ccid2.h" + +static int ccid2_debug; + +#if 0 +#define CCID2_DEBUG +#endif + +#ifdef CCID2_DEBUG +#define ccid2_pr_debug(format, a...) \ + do { if (ccid2_debug) \ + printk(KERN_DEBUG "%s: " format, __FUNCTION__, ##a); \ + } while (0) +#else +#define ccid2_pr_debug(format, a...) +#endif + +static const int ccid2_seq_len = 128; + +static inline struct ccid2_hc_tx_sock *ccid2_hc_tx_sk(const struct sock *sk) +{ + return dccp_sk(sk)->dccps_hc_tx_ccid_private; +} + +static inline struct ccid2_hc_rx_sock *ccid2_hc_rx_sk(const struct sock *sk) +{ + return dccp_sk(sk)->dccps_hc_rx_ccid_private; +} + +#ifdef CCID2_DEBUG +static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx) +{ + int len = 0; + struct ccid2_seq *seqp; + int pipe = 0; + + seqp = hctx->ccid2hctx_seqh; + + /* there is data in the chain */ + if (seqp != hctx->ccid2hctx_seqt) { + seqp = seqp->ccid2s_prev; + len++; + if (!seqp->ccid2s_acked) + pipe++; + + while (seqp != hctx->ccid2hctx_seqt) { + struct ccid2_seq *prev; + + prev = seqp->ccid2s_prev; + len++; + if (!prev->ccid2s_acked) + pipe++; + + /* packets are sent sequentially */ + BUG_ON(seqp->ccid2s_seq <= prev->ccid2s_seq); + BUG_ON(seqp->ccid2s_sent < prev->ccid2s_sent); + BUG_ON(len > ccid2_seq_len); + + seqp = prev; + } + } + + BUG_ON(pipe != hctx->ccid2hctx_pipe); + ccid2_pr_debug("len of chain=%d\n", len); + + do { + seqp = seqp->ccid2s_prev; + len++; + BUG_ON(len > ccid2_seq_len); + } while(seqp != hctx->ccid2hctx_seqh); + + BUG_ON(len != ccid2_seq_len); + ccid2_pr_debug("total len=%d\n", len); +} +#else +#define ccid2_hc_tx_check_sanity(hctx) do {} while (0) +#endif + +static int ccid2_hc_tx_send_packet(struct sock *sk, + struct sk_buff *skb, int len) +{ + struct ccid2_hc_tx_sock *hctx; + + switch (DCCP_SKB_CB(skb)->dccpd_type) { + case 0: /* XXX data packets from userland come through like this */ + case DCCP_PKT_DATA: + case DCCP_PKT_DATAACK: + break; + /* No congestion control on other packets */ + default: + return 0; + } + + hctx = ccid2_hc_tx_sk(sk); + + ccid2_pr_debug("pipe=%d cwnd=%d\n", hctx->ccid2hctx_pipe, + hctx->ccid2hctx_cwnd); + + if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd) { + /* OK we can send... make sure previous packet was sent off */ + if (!hctx->ccid2hctx_sendwait) { + hctx->ccid2hctx_sendwait = 1; + return 0; + } + } + + return 100; /* XXX */ +} + +static void ccid2_change_l_ack_ratio(struct sock *sk, int val) +{ + struct dccp_sock *dp = dccp_sk(sk); + /* + * XXX I don't really agree with val != 2. If cwnd is 1, ack ratio + * should be 1... it shouldn't be allowed to become 2. + * -sorbo. + */ + if (val != 2) { + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + int max = hctx->ccid2hctx_cwnd / 2; + + /* round up */ + if (hctx->ccid2hctx_cwnd & 1) + max++; + + if (val > max) + val = max; + } + + ccid2_pr_debug("changing local ack ratio to %d\n", val); + WARN_ON(val <= 0); + dp->dccps_l_ack_ratio = val; +} + +static void ccid2_change_cwnd(struct sock *sk, int val) +{ + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + + if (val == 0) + val = 1; + + /* XXX do we need to change ack ratio? */ + ccid2_pr_debug("change cwnd to %d\n", val); + + BUG_ON(val < 1); + hctx->ccid2hctx_cwnd = val; +} + +static void ccid2_start_rto_timer(struct sock *sk); + +static void ccid2_hc_tx_rto_expire(unsigned long data) +{ + struct sock *sk = (struct sock *)data; + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + long s; + + /* XXX I don't think i'm locking correctly + * -sorbo. + */ + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) { + sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer, + jiffies + HZ / 5); + goto out; + } + + ccid2_pr_debug("RTO_EXPIRE\n"); + + ccid2_hc_tx_check_sanity(hctx); + + /* back-off timer */ + hctx->ccid2hctx_rto <<= 1; + + s = hctx->ccid2hctx_rto / HZ; + if (s > 60) + hctx->ccid2hctx_rto = 60 * HZ; + + ccid2_start_rto_timer(sk); + + /* adjust pipe, cwnd etc */ + hctx->ccid2hctx_pipe = 0; + hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd >> 1; + if (hctx->ccid2hctx_ssthresh < 2) + hctx->ccid2hctx_ssthresh = 2; + ccid2_change_cwnd(sk, 1); + + /* clear state about stuff we sent */ + hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh; + hctx->ccid2hctx_ssacks = 0; + hctx->ccid2hctx_acks = 0; + hctx->ccid2hctx_sent = 0; + + /* clear ack ratio state. */ + hctx->ccid2hctx_arsent = 0; + hctx->ccid2hctx_ackloss = 0; + hctx->ccid2hctx_rpseq = 0; + hctx->ccid2hctx_rpdupack = -1; + ccid2_change_l_ack_ratio(sk, 1); + ccid2_hc_tx_check_sanity(hctx); +out: + bh_unlock_sock(sk); +/* sock_put(sk); */ +} + +static void ccid2_start_rto_timer(struct sock *sk) +{ + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + + ccid2_pr_debug("setting RTO timeout=%ld\n", hctx->ccid2hctx_rto); + + BUG_ON(timer_pending(&hctx->ccid2hctx_rtotimer)); + sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer, + jiffies + hctx->ccid2hctx_rto); +} + +static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, int len) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + u64 seq; + + ccid2_hc_tx_check_sanity(hctx); + + BUG_ON(!hctx->ccid2hctx_sendwait); + hctx->ccid2hctx_sendwait = 0; + hctx->ccid2hctx_pipe++; + BUG_ON(hctx->ccid2hctx_pipe < 0); + + /* There is an issue. What if another packet is sent between + * packet_send() and packet_sent(). Then the sequence number would be + * wrong. + * -sorbo. + */ + seq = dp->dccps_gss; + + hctx->ccid2hctx_seqh->ccid2s_seq = seq; + hctx->ccid2hctx_seqh->ccid2s_acked = 0; + hctx->ccid2hctx_seqh->ccid2s_sent = jiffies; + hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqh->ccid2s_next; + + ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd, + hctx->ccid2hctx_pipe); + + if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt) { + /* XXX allocate more space */ + WARN_ON(1); + } + + hctx->ccid2hctx_sent++; + + /* Ack Ratio. Need to maintain a concept of how many windows we sent */ + hctx->ccid2hctx_arsent++; + /* We had an ack loss in this window... */ + if (hctx->ccid2hctx_ackloss) { + if (hctx->ccid2hctx_arsent >= hctx->ccid2hctx_cwnd) { + hctx->ccid2hctx_arsent = 0; + hctx->ccid2hctx_ackloss = 0; + } + } + /* No acks lost up to now... */ + else { + /* decrease ack ratio if enough packets were sent */ + if (dp->dccps_l_ack_ratio > 1) { + /* XXX don't calculate denominator each time */ + int denom; + + denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio - + dp->dccps_l_ack_ratio; + denom = hctx->ccid2hctx_cwnd * hctx->ccid2hctx_cwnd / denom; + + if (hctx->ccid2hctx_arsent >= denom) { + ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1); + hctx->ccid2hctx_arsent = 0; + } + } + /* we can't increase ack ratio further [1] */ + else { + hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/ + } + } + + /* setup RTO timer */ + if (!timer_pending(&hctx->ccid2hctx_rtotimer)) { + ccid2_start_rto_timer(sk); + } +#ifdef CCID2_DEBUG + ccid2_pr_debug("pipe=%d\n", hctx->ccid2hctx_pipe); + ccid2_pr_debug("Sent: seq=%llu\n", seq); + do { + struct ccid2_seq *seqp = hctx->ccid2hctx_seqt; + + while (seqp != hctx->ccid2hctx_seqh) { + ccid2_pr_debug("out seq=%llu acked=%d time=%lu\n", + seqp->ccid2s_seq, seqp->ccid2s_acked, + seqp->ccid2s_sent); + seqp = seqp->ccid2s_next; + } + } while(0); + ccid2_pr_debug("=========\n"); + ccid2_hc_tx_check_sanity(hctx); +#endif +} + +/* XXX Lame code duplication! + * returns -1 if none was found. + * else returns the next offset to use in the function call. + */ +static int ccid2_ackvector(struct sock *sk, struct sk_buff *skb, int offset, + unsigned char **vec, unsigned char *veclen) +{ + const struct dccp_hdr *dh = dccp_hdr(skb); + unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb); + unsigned char *opt_ptr; + const unsigned char *opt_end = (unsigned char *)dh + + (dh->dccph_doff * 4); + unsigned char opt, len; + unsigned char *value; + + BUG_ON(offset < 0); + options += offset; + opt_ptr = options; + if (opt_ptr >= opt_end) + return -1; + + while (opt_ptr != opt_end) { + opt = *opt_ptr++; + len = 0; + value = NULL; + + /* Check if this isn't a single byte option */ + if (opt > DCCPO_MAX_RESERVED) { + if (opt_ptr == opt_end) + goto out_invalid_option; + + len = *opt_ptr++; + if (len < 3) + goto out_invalid_option; + /* + * Remove the type and len fields, leaving + * just the value size + */ + len -= 2; + value = opt_ptr; + opt_ptr += len; + + if (opt_ptr > opt_end) + goto out_invalid_option; + } + + switch (opt) { + case DCCPO_ACK_VECTOR_0: + case DCCPO_ACK_VECTOR_1: + *vec = value; + *veclen = len; + return offset + (opt_ptr - options); + break; + } + } + + return -1; + +out_invalid_option: + BUG_ON(1); /* should never happen... options were previously parsed ! */ + return -1; +} + +static void ccid2_hc_tx_kill_rto_timer(struct ccid2_hc_tx_sock *hctx) +{ + if (del_timer(&hctx->ccid2hctx_rtotimer)) + ccid2_pr_debug("deleted RTO timer\n"); +} + +static inline void ccid2_new_ack(struct sock *sk, + struct ccid2_seq *seqp, + unsigned int *maxincr) +{ + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + + /* slow start */ + if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) { + hctx->ccid2hctx_acks = 0; + + /* We can increase cwnd at most maxincr [ack_ratio/2] */ + if (*maxincr) { + /* increase every 2 acks */ + hctx->ccid2hctx_ssacks++; + if (hctx->ccid2hctx_ssacks == 2) { + ccid2_change_cwnd(sk, hctx->ccid2hctx_cwnd + 1); + hctx->ccid2hctx_ssacks = 0; + *maxincr = *maxincr - 1; + } + } + /* increased cwnd enough for this single ack */ + else { + hctx->ccid2hctx_ssacks = 0; + } + } + else { + hctx->ccid2hctx_ssacks = 0; + hctx->ccid2hctx_acks++; + + if (hctx->ccid2hctx_acks >= hctx->ccid2hctx_cwnd) { + ccid2_change_cwnd(sk, hctx->ccid2hctx_cwnd + 1); + hctx->ccid2hctx_acks = 0; + } + } + + /* update RTO */ + if (hctx->ccid2hctx_srtt == -1 || + (jiffies - hctx->ccid2hctx_lastrtt) >= hctx->ccid2hctx_srtt) { + unsigned long r = jiffies - seqp->ccid2s_sent; + int s; + + /* first measurement */ + if (hctx->ccid2hctx_srtt == -1) { + ccid2_pr_debug("R: %lu Time=%lu seq=%llu\n", + r, jiffies, seqp->ccid2s_seq); + hctx->ccid2hctx_srtt = r; + hctx->ccid2hctx_rttvar = r >> 1; + } + else { + /* RTTVAR */ + long tmp = hctx->ccid2hctx_srtt - r; + if (tmp < 0) + tmp *= -1; + + tmp >>= 2; + hctx->ccid2hctx_rttvar *= 3; + hctx->ccid2hctx_rttvar >>= 2; + hctx->ccid2hctx_rttvar += tmp; + + /* SRTT */ + hctx->ccid2hctx_srtt *= 7; + hctx->ccid2hctx_srtt >>= 3; + tmp = r >> 3; + hctx->ccid2hctx_srtt += tmp; + } + s = hctx->ccid2hctx_rttvar << 2; + /* clock granularity is 1 when based on jiffies */ + if (!s) + s = 1; + hctx->ccid2hctx_rto = hctx->ccid2hctx_srtt + s; + + /* must be at least a second */ + s = hctx->ccid2hctx_rto / HZ; + /* DCCP doesn't require this [but I like it cuz my code sux] */ +#if 1 + if (s < 1) + hctx->ccid2hctx_rto = HZ; +#endif + /* max 60 seconds */ + if (s > 60) + hctx->ccid2hctx_rto = HZ * 60; + + hctx->ccid2hctx_lastrtt = jiffies; + + ccid2_pr_debug("srtt: %ld rttvar: %ld rto: %ld (HZ=%d) R=%lu\n", + hctx->ccid2hctx_srtt, hctx->ccid2hctx_rttvar, + hctx->ccid2hctx_rto, HZ, r); + hctx->ccid2hctx_sent = 0; + } + + /* we got a new ack, so re-start RTO timer */ + ccid2_hc_tx_kill_rto_timer(hctx); + ccid2_start_rto_timer(sk); +} + +static void ccid2_hc_tx_dec_pipe(struct ccid2_hc_tx_sock *hctx) +{ + hctx->ccid2hctx_pipe--; + BUG_ON(hctx->ccid2hctx_pipe < 0); + + if (hctx->ccid2hctx_pipe == 0) + ccid2_hc_tx_kill_rto_timer(hctx); +} + +static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + u64 ackno, seqno; + struct ccid2_seq *seqp; + unsigned char *vector; + unsigned char veclen; + int offset = 0; + int done = 0; + int loss = 0; + unsigned int maxincr = 0; + + ccid2_hc_tx_check_sanity(hctx); + /* check reverse path congestion */ + seqno = DCCP_SKB_CB(skb)->dccpd_seq; + + /* XXX this whole "algorithm" is broken. Need to fix it to keep track + * of the seqnos of the dupacks so that rpseq and rpdupack are correct + * -sorbo. + */ + /* need to bootstrap */ + if (hctx->ccid2hctx_rpdupack == -1) { + hctx->ccid2hctx_rpdupack = 0; + hctx->ccid2hctx_rpseq = seqno; + } + else { + /* check if packet is consecutive */ + if ((hctx->ccid2hctx_rpseq + 1) == seqno) { + hctx->ccid2hctx_rpseq++; + } + /* it's a later packet */ + else if (after48(seqno, hctx->ccid2hctx_rpseq)) { + hctx->ccid2hctx_rpdupack++; + + /* check if we got enough dupacks */ + if (hctx->ccid2hctx_rpdupack >= + hctx->ccid2hctx_numdupack) { + + hctx->ccid2hctx_rpdupack = -1; /* XXX lame */ + hctx->ccid2hctx_rpseq = 0; + + ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio << 1); + } + } + } + + /* check forward path congestion */ + /* still didn't send out new data packets */ + if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt) + return; + + switch (DCCP_SKB_CB(skb)->dccpd_type) { + case DCCP_PKT_ACK: + case DCCP_PKT_DATAACK: + break; + + default: + return; + } + + ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; + seqp = hctx->ccid2hctx_seqh->ccid2s_prev; + + /* If in slow-start, cwnd can increase at most Ack Ratio / 2 packets for + * this single ack. I round up. + * -sorbo. + */ + maxincr = dp->dccps_l_ack_ratio >> 1; + maxincr++; + + /* go through all ack vectors */ + while ((offset = ccid2_ackvector(sk, skb, offset, + &vector, &veclen)) != -1) { + /* go through this ack vector */ + while (veclen--) { + const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; + u64 ackno_end_rl; + + dccp_set_seqno(&ackno_end_rl, ackno - rl); + ccid2_pr_debug("ackvec start:%llu end:%llu\n", ackno, + ackno_end_rl); + /* if the seqno we are analyzing is larger than the + * current ackno, then move towards the tail of our + * seqnos. + */ + while (after48(seqp->ccid2s_seq, ackno)) { + if (seqp == hctx->ccid2hctx_seqt) { + done = 1; + break; + } + seqp = seqp->ccid2s_prev; + } + if (done) + break; + + /* check all seqnos in the range of the vector + * run length + */ + while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) { + const u8 state = (*vector & + DCCP_ACKVEC_STATE_MASK) >> 6; + + /* new packet received or marked */ + if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED && + !seqp->ccid2s_acked) { + if (state == + DCCP_ACKVEC_STATE_ECN_MARKED) { + loss = 1; + } + else { + ccid2_new_ack(sk, seqp, + &maxincr); + } + + seqp->ccid2s_acked = 1; + ccid2_pr_debug("Got ack for %llu\n", + seqp->ccid2s_seq); + ccid2_hc_tx_dec_pipe(hctx); + } + if (seqp == hctx->ccid2hctx_seqt) { + done = 1; + break; + } + seqp = seqp->ccid2s_next; + } + if (done) + break; + + + dccp_set_seqno(&ackno, ackno_end_rl - 1); + vector++; + } + if (done) + break; + } + + /* The state about what is acked should be correct now + * Check for NUMDUPACK + */ + seqp = hctx->ccid2hctx_seqh->ccid2s_prev; + done = 0; + while (1) { + if (seqp->ccid2s_acked) { + done++; + if (done == hctx->ccid2hctx_numdupack) { + break; + } + } + if (seqp == hctx->ccid2hctx_seqt) { + break; + } + seqp = seqp->ccid2s_prev; + } + + /* If there are at least 3 acknowledgements, anything unacknowledged + * below the last sequence number is considered lost + */ + if (done == hctx->ccid2hctx_numdupack) { + struct ccid2_seq *last_acked = seqp; + + /* check for lost packets */ + while (1) { + if (!seqp->ccid2s_acked) { + loss = 1; + ccid2_hc_tx_dec_pipe(hctx); + } + if (seqp == hctx->ccid2hctx_seqt) + break; + seqp = seqp->ccid2s_prev; + } + + hctx->ccid2hctx_seqt = last_acked; + } + + /* trim acked packets in tail */ + while (hctx->ccid2hctx_seqt != hctx->ccid2hctx_seqh) { + if (!hctx->ccid2hctx_seqt->ccid2s_acked) + break; + + hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqt->ccid2s_next; + } + + if (loss) { + /* XXX do bit shifts guarantee a 0 as the new bit? */ + ccid2_change_cwnd(sk, hctx->ccid2hctx_cwnd >> 1); + hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd; + if (hctx->ccid2hctx_ssthresh < 2) + hctx->ccid2hctx_ssthresh = 2; + } + + ccid2_hc_tx_check_sanity(hctx); +} + +static int ccid2_hc_tx_init(struct sock *sk) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_tx_sock *hctx; + int seqcount = ccid2_seq_len; + int i; + + dp->dccps_hc_tx_ccid_private = kzalloc(sizeof(*hctx), gfp_any()); + if (dp->dccps_hc_tx_ccid_private == NULL) + return -ENOMEM; + + hctx = ccid2_hc_tx_sk(sk); + + /* XXX init variables with proper values */ + hctx->ccid2hctx_cwnd = 1; + hctx->ccid2hctx_ssthresh = 10; + hctx->ccid2hctx_numdupack = 3; + + /* XXX init ~ to window size... */ + hctx->ccid2hctx_seqbuf = kmalloc(sizeof(*hctx->ccid2hctx_seqbuf) * + seqcount, gfp_any()); + if (hctx->ccid2hctx_seqbuf == NULL) { + kfree(dp->dccps_hc_tx_ccid_private); + dp->dccps_hc_tx_ccid_private = NULL; + return -ENOMEM; + } + for (i = 0; i < (seqcount - 1); i++) { + hctx->ccid2hctx_seqbuf[i].ccid2s_next = + &hctx->ccid2hctx_seqbuf[i + 1]; + hctx->ccid2hctx_seqbuf[i + 1].ccid2s_prev = + &hctx->ccid2hctx_seqbuf[i]; + } + hctx->ccid2hctx_seqbuf[seqcount - 1].ccid2s_next = + hctx->ccid2hctx_seqbuf; + hctx->ccid2hctx_seqbuf->ccid2s_prev = + &hctx->ccid2hctx_seqbuf[seqcount - 1]; + + hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqbuf; + hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh; + hctx->ccid2hctx_sent = 0; + hctx->ccid2hctx_rto = 3 * HZ; + hctx->ccid2hctx_srtt = -1; + hctx->ccid2hctx_rttvar = -1; + hctx->ccid2hctx_lastrtt = 0; + hctx->ccid2hctx_rpdupack = -1; + + hctx->ccid2hctx_rtotimer.function = &ccid2_hc_tx_rto_expire; + hctx->ccid2hctx_rtotimer.data = (unsigned long)sk; + init_timer(&hctx->ccid2hctx_rtotimer); + + ccid2_hc_tx_check_sanity(hctx); + return 0; +} + +static void ccid2_hc_tx_exit(struct sock *sk) +{ + struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; + + ccid2_hc_tx_kill_rto_timer(hctx); + + kfree(hctx->ccid2hctx_seqbuf); + + kfree(dp->dccps_hc_tx_ccid_private); + dp->dccps_hc_tx_ccid_private = NULL; +} + +static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) +{ + const struct dccp_sock *dp = dccp_sk(sk); + struct ccid2_hc_rx_sock *hcrx = ccid2_hc_rx_sk(sk); + + switch (DCCP_SKB_CB(skb)->dccpd_type) { + case DCCP_PKT_DATA: + case DCCP_PKT_DATAACK: + hcrx->ccid2hcrx_data++; + if (hcrx->ccid2hcrx_data >= dp->dccps_r_ack_ratio) { + dccp_send_ack(sk); + hcrx->ccid2hcrx_data = 0; + } + break; + } +} + +static int ccid2_hc_rx_init(struct sock *sk) +{ + struct dccp_sock *dp = dccp_sk(sk); + dp->dccps_hc_rx_ccid_private = kzalloc(sizeof(struct ccid2_hc_rx_sock), + gfp_any()); + return dp->dccps_hc_rx_ccid_private == NULL ? -ENOMEM : 0; +} + +static void ccid2_hc_rx_exit(struct sock *sk) +{ + struct dccp_sock *dp = dccp_sk(sk); + + kfree(dp->dccps_hc_rx_ccid_private); + dp->dccps_hc_rx_ccid_private = NULL; +} + +static struct ccid ccid2 = { + .ccid_id = 2, + .ccid_name = "ccid2", + .ccid_owner = THIS_MODULE, + .ccid_hc_tx_init = ccid2_hc_tx_init, + .ccid_hc_tx_exit = ccid2_hc_tx_exit, + .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet, + .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent, + .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv, + .ccid_hc_rx_init = ccid2_hc_rx_init, + .ccid_hc_rx_exit = ccid2_hc_rx_exit, + .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv, +}; + +module_param(ccid2_debug, int, 0444); +MODULE_PARM_DESC(ccid2_debug, "Enable debug messages"); + +static __init int ccid2_module_init(void) +{ + return ccid_register(&ccid2); +} +module_init(ccid2_module_init); + +static __exit void ccid2_module_exit(void) +{ + ccid_unregister(&ccid2); +} +module_exit(ccid2_module_exit); + +MODULE_AUTHOR("Andrea Bittau "); +MODULE_DESCRIPTION("DCCP TCP CCID2 CCID"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("net-dccp-ccid-2"); -- cgit v1.2.3 From 77ff72d528d5b9d30a47f42f364ba34d931f9da3 Mon Sep 17 00:00:00 2001 From: Andrea Bittau Date: Mon, 20 Mar 2006 17:57:52 -0800 Subject: [DCCP] CCID2: Drop sock reference count on timer expiration and reset. There was a hybrid use of standard timers and sk_timers. This caused the reference count of the sock to be incorrect when resetting the RTO timer. The sock reference count should now be correct, enabling its destruction, and allowing the DCCP module to be unloaded. Signed-off-by: Andrea Bittau Signed-off-by: Arnaldo Carvalho de Melo --- net/dccp/ccids/ccid2.c | 26 +++++++++++++++----------- 1 file changed, 15 insertions(+), 11 deletions(-) (limited to 'net/dccp/ccids/ccid2.c') diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c index 4a7b87512560..3328d23c4be7 100644 --- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -234,7 +234,7 @@ static void ccid2_hc_tx_rto_expire(unsigned long data) ccid2_hc_tx_check_sanity(hctx); out: bh_unlock_sock(sk); -/* sock_put(sk); */ + sock_put(sk); } static void ccid2_start_rto_timer(struct sock *sk) @@ -399,10 +399,12 @@ out_invalid_option: return -1; } -static void ccid2_hc_tx_kill_rto_timer(struct ccid2_hc_tx_sock *hctx) +static void ccid2_hc_tx_kill_rto_timer(struct sock *sk) { - if (del_timer(&hctx->ccid2hctx_rtotimer)) - ccid2_pr_debug("deleted RTO timer\n"); + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + + sk_stop_timer(sk, &hctx->ccid2hctx_rtotimer); + ccid2_pr_debug("deleted RTO timer\n"); } static inline void ccid2_new_ack(struct sock *sk, @@ -496,17 +498,19 @@ static inline void ccid2_new_ack(struct sock *sk, } /* we got a new ack, so re-start RTO timer */ - ccid2_hc_tx_kill_rto_timer(hctx); + ccid2_hc_tx_kill_rto_timer(sk); ccid2_start_rto_timer(sk); } -static void ccid2_hc_tx_dec_pipe(struct ccid2_hc_tx_sock *hctx) +static void ccid2_hc_tx_dec_pipe(struct sock *sk) { + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + hctx->ccid2hctx_pipe--; BUG_ON(hctx->ccid2hctx_pipe < 0); if (hctx->ccid2hctx_pipe == 0) - ccid2_hc_tx_kill_rto_timer(hctx); + ccid2_hc_tx_kill_rto_timer(sk); } static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) @@ -627,7 +631,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) seqp->ccid2s_acked = 1; ccid2_pr_debug("Got ack for %llu\n", seqp->ccid2s_seq); - ccid2_hc_tx_dec_pipe(hctx); + ccid2_hc_tx_dec_pipe(sk); } if (seqp == hctx->ccid2hctx_seqt) { done = 1; @@ -674,7 +678,7 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) while (1) { if (!seqp->ccid2s_acked) { loss = 1; - ccid2_hc_tx_dec_pipe(hctx); + ccid2_hc_tx_dec_pipe(sk); } if (seqp == hctx->ccid2hctx_seqt) break; @@ -760,9 +764,9 @@ static int ccid2_hc_tx_init(struct sock *sk) static void ccid2_hc_tx_exit(struct sock *sk) { struct dccp_sock *dp = dccp_sk(sk); - struct ccid2_hc_tx_sock *hctx = dp->dccps_hc_tx_ccid_private; + struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); - ccid2_hc_tx_kill_rto_timer(hctx); + ccid2_hc_tx_kill_rto_timer(sk); kfree(hctx->ccid2hctx_seqbuf); -- cgit v1.2.3 From 91f0ebf7b6d5cb2b6e818d48587566144821babe Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 20 Mar 2006 19:21:44 -0800 Subject: [DCCP] CCID: Improve CCID infrastructure 1. No need for ->ccid_init nor ->ccid_exit, this is what module_{init,exit} does and anynways neither ccid2 nor ccid3 were using it. 2. Rename struct ccid to struct ccid_operations and introduce struct ccid with a pointer to ccid_operations and rigth after it the rx or tx private state. 3. Remove the pointer to the state of the half connections from struct dccp_sock, now its derived thru ccid_priv() from the ccid pointer. Now we also can implement the setsockopt for changing the CCID easily as no ccid init routines can affect struct dccp_sock in any way that prevents other CCIDs from working if a CCID switch operation is asked by apps. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/dccp/ccids/ccid2.c | 55 ++++++++------------------------------------------ 1 file changed, 8 insertions(+), 47 deletions(-) (limited to 'net/dccp/ccids/ccid2.c') diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c index 3328d23c4be7..b40c4569a820 100644 --- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -52,16 +52,6 @@ static int ccid2_debug; static const int ccid2_seq_len = 128; -static inline struct ccid2_hc_tx_sock *ccid2_hc_tx_sk(const struct sock *sk) -{ - return dccp_sk(sk)->dccps_hc_tx_ccid_private; -} - -static inline struct ccid2_hc_rx_sock *ccid2_hc_rx_sk(const struct sock *sk) -{ - return dccp_sk(sk)->dccps_hc_rx_ccid_private; -} - #ifdef CCID2_DEBUG static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx) { @@ -707,19 +697,12 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) ccid2_hc_tx_check_sanity(hctx); } -static int ccid2_hc_tx_init(struct sock *sk) +static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); - struct ccid2_hc_tx_sock *hctx; + struct ccid2_hc_tx_sock *hctx = ccid_priv(ccid); int seqcount = ccid2_seq_len; int i; - dp->dccps_hc_tx_ccid_private = kzalloc(sizeof(*hctx), gfp_any()); - if (dp->dccps_hc_tx_ccid_private == NULL) - return -ENOMEM; - - hctx = ccid2_hc_tx_sk(sk); - /* XXX init variables with proper values */ hctx->ccid2hctx_cwnd = 1; hctx->ccid2hctx_ssthresh = 10; @@ -728,11 +711,9 @@ static int ccid2_hc_tx_init(struct sock *sk) /* XXX init ~ to window size... */ hctx->ccid2hctx_seqbuf = kmalloc(sizeof(*hctx->ccid2hctx_seqbuf) * seqcount, gfp_any()); - if (hctx->ccid2hctx_seqbuf == NULL) { - kfree(dp->dccps_hc_tx_ccid_private); - dp->dccps_hc_tx_ccid_private = NULL; + if (hctx->ccid2hctx_seqbuf == NULL) return -ENOMEM; - } + for (i = 0; i < (seqcount - 1); i++) { hctx->ccid2hctx_seqbuf[i].ccid2s_next = &hctx->ccid2hctx_seqbuf[i + 1]; @@ -763,15 +744,11 @@ static int ccid2_hc_tx_init(struct sock *sk) static void ccid2_hc_tx_exit(struct sock *sk) { - struct dccp_sock *dp = dccp_sk(sk); struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); ccid2_hc_tx_kill_rto_timer(sk); - kfree(hctx->ccid2hctx_seqbuf); - - kfree(dp->dccps_hc_tx_ccid_private); - dp->dccps_hc_tx_ccid_private = NULL; + hctx->ccid2hctx_seqbuf = NULL; } static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) @@ -791,33 +768,17 @@ static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) } } -static int ccid2_hc_rx_init(struct sock *sk) -{ - struct dccp_sock *dp = dccp_sk(sk); - dp->dccps_hc_rx_ccid_private = kzalloc(sizeof(struct ccid2_hc_rx_sock), - gfp_any()); - return dp->dccps_hc_rx_ccid_private == NULL ? -ENOMEM : 0; -} - -static void ccid2_hc_rx_exit(struct sock *sk) -{ - struct dccp_sock *dp = dccp_sk(sk); - - kfree(dp->dccps_hc_rx_ccid_private); - dp->dccps_hc_rx_ccid_private = NULL; -} - -static struct ccid ccid2 = { +static struct ccid_operations ccid2 = { .ccid_id = 2, .ccid_name = "ccid2", .ccid_owner = THIS_MODULE, + .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock), .ccid_hc_tx_init = ccid2_hc_tx_init, .ccid_hc_tx_exit = ccid2_hc_tx_exit, .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet, .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent, .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv, - .ccid_hc_rx_init = ccid2_hc_rx_init, - .ccid_hc_rx_exit = ccid2_hc_rx_exit, + .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock), .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv, }; -- cgit v1.2.3 From c0c736db7ef4a7bdc1a28f3de751cc7e9f720313 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 20 Mar 2006 22:05:37 -0800 Subject: [DCCP] ccid2: coding style cleanups No changes in the logic where made. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- net/dccp/ccids/ccid2.c | 76 +++++++++++++++++--------------------------------- 1 file changed, 26 insertions(+), 50 deletions(-) (limited to 'net/dccp/ccids/ccid2.c') diff --git a/net/dccp/ccids/ccid2.c b/net/dccp/ccids/ccid2.c index b40c4569a820..d4f9e2d33453 100644 --- a/net/dccp/ccids/ccid2.c +++ b/net/dccp/ccids/ccid2.c @@ -37,10 +37,7 @@ static int ccid2_debug; -#if 0 -#define CCID2_DEBUG -#endif - +#undef CCID2_DEBUG #ifdef CCID2_DEBUG #define ccid2_pr_debug(format, a...) \ do { if (ccid2_debug) \ @@ -56,10 +53,8 @@ static const int ccid2_seq_len = 128; static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx) { int len = 0; - struct ccid2_seq *seqp; int pipe = 0; - - seqp = hctx->ccid2hctx_seqh; + struct ccid2_seq *seqp = hctx->ccid2hctx_seqh; /* there is data in the chain */ if (seqp != hctx->ccid2hctx_seqt) { @@ -69,9 +64,8 @@ static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx) pipe++; while (seqp != hctx->ccid2hctx_seqt) { - struct ccid2_seq *prev; + struct ccid2_seq *prev = seqp->ccid2s_prev; - prev = seqp->ccid2s_prev; len++; if (!prev->ccid2s_acked) pipe++; @@ -92,7 +86,7 @@ static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx) seqp = seqp->ccid2s_prev; len++; BUG_ON(len > ccid2_seq_len); - } while(seqp != hctx->ccid2hctx_seqh); + } while (seqp != hctx->ccid2hctx_seqh); BUG_ON(len != ccid2_seq_len); ccid2_pr_debug("total len=%d\n", len); @@ -141,7 +135,7 @@ static void ccid2_change_l_ack_ratio(struct sock *sk, int val) * -sorbo. */ if (val != 2) { - struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); + const struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); int max = hctx->ccid2hctx_cwnd / 2; /* round up */ @@ -179,9 +173,6 @@ static void ccid2_hc_tx_rto_expire(unsigned long data) struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); long s; - /* XXX I don't think i'm locking correctly - * -sorbo. - */ bh_lock_sock(sk); if (sock_owned_by_user(sk)) { sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer, @@ -278,36 +269,33 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, int len) /* We had an ack loss in this window... */ if (hctx->ccid2hctx_ackloss) { if (hctx->ccid2hctx_arsent >= hctx->ccid2hctx_cwnd) { - hctx->ccid2hctx_arsent = 0; - hctx->ccid2hctx_ackloss = 0; + hctx->ccid2hctx_arsent = 0; + hctx->ccid2hctx_ackloss = 0; } - } - /* No acks lost up to now... */ - else { + } else { + /* No acks lost up to now... */ /* decrease ack ratio if enough packets were sent */ if (dp->dccps_l_ack_ratio > 1) { /* XXX don't calculate denominator each time */ - int denom; + int denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio - + dp->dccps_l_ack_ratio; - denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio - - dp->dccps_l_ack_ratio; denom = hctx->ccid2hctx_cwnd * hctx->ccid2hctx_cwnd / denom; if (hctx->ccid2hctx_arsent >= denom) { ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1); hctx->ccid2hctx_arsent = 0; } - } - /* we can't increase ack ratio further [1] */ - else { + } else { + /* we can't increase ack ratio further [1] */ hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/ } } /* setup RTO timer */ - if (!timer_pending(&hctx->ccid2hctx_rtotimer)) { + if (!timer_pending(&hctx->ccid2hctx_rtotimer)) ccid2_start_rto_timer(sk); - } + #ifdef CCID2_DEBUG ccid2_pr_debug("pipe=%d\n", hctx->ccid2hctx_pipe); ccid2_pr_debug("Sent: seq=%llu\n", seq); @@ -320,7 +308,7 @@ static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, int len) seqp->ccid2s_sent); seqp = seqp->ccid2s_next; } - } while(0); + } while (0); ccid2_pr_debug("=========\n"); ccid2_hc_tx_check_sanity(hctx); #endif @@ -378,7 +366,6 @@ static int ccid2_ackvector(struct sock *sk, struct sk_buff *skb, int offset, *vec = value; *veclen = len; return offset + (opt_ptr - options); - break; } } @@ -416,13 +403,11 @@ static inline void ccid2_new_ack(struct sock *sk, hctx->ccid2hctx_ssacks = 0; *maxincr = *maxincr - 1; } - } - /* increased cwnd enough for this single ack */ - else { + } else { + /* increased cwnd enough for this single ack */ hctx->ccid2hctx_ssacks = 0; } - } - else { + } else { hctx->ccid2hctx_ssacks = 0; hctx->ccid2hctx_acks++; @@ -444,8 +429,7 @@ static inline void ccid2_new_ack(struct sock *sk, r, jiffies, seqp->ccid2s_seq); hctx->ccid2hctx_srtt = r; hctx->ccid2hctx_rttvar = r >> 1; - } - else { + } else { /* RTTVAR */ long tmp = hctx->ccid2hctx_srtt - r; if (tmp < 0) @@ -528,12 +512,10 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) if (hctx->ccid2hctx_rpdupack == -1) { hctx->ccid2hctx_rpdupack = 0; hctx->ccid2hctx_rpseq = seqno; - } - else { + } else { /* check if packet is consecutive */ - if ((hctx->ccid2hctx_rpseq + 1) == seqno) { + if ((hctx->ccid2hctx_rpseq + 1) == seqno) hctx->ccid2hctx_rpseq++; - } /* it's a later packet */ else if (after48(seqno, hctx->ccid2hctx_rpseq)) { hctx->ccid2hctx_rpdupack++; @@ -541,7 +523,6 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) /* check if we got enough dupacks */ if (hctx->ccid2hctx_rpdupack >= hctx->ccid2hctx_numdupack) { - hctx->ccid2hctx_rpdupack = -1; /* XXX lame */ hctx->ccid2hctx_rpseq = 0; @@ -559,7 +540,6 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) case DCCP_PKT_ACK: case DCCP_PKT_DATAACK: break; - default: return; } @@ -612,11 +592,9 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) if (state == DCCP_ACKVEC_STATE_ECN_MARKED) { loss = 1; - } - else { + } else ccid2_new_ack(sk, seqp, &maxincr); - } seqp->ccid2s_acked = 1; ccid2_pr_debug("Got ack for %llu\n", @@ -648,13 +626,11 @@ static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) while (1) { if (seqp->ccid2s_acked) { done++; - if (done == hctx->ccid2hctx_numdupack) { + if (done == hctx->ccid2hctx_numdupack) break; - } } - if (seqp == hctx->ccid2hctx_seqt) { + if (seqp == hctx->ccid2hctx_seqt) break; - } seqp = seqp->ccid2s_prev; } @@ -798,6 +774,6 @@ static __exit void ccid2_module_exit(void) module_exit(ccid2_module_exit); MODULE_AUTHOR("Andrea Bittau "); -MODULE_DESCRIPTION("DCCP TCP CCID2 CCID"); +MODULE_DESCRIPTION("DCCP TCP-Like (CCID2) CCID"); MODULE_LICENSE("GPL"); MODULE_ALIAS("net-dccp-ccid-2"); -- cgit v1.2.3