Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 1 | /* |
| 2 | * net/dccp/ccids/ccid2.c |
| 3 | * |
| 4 | * Copyright (c) 2005, 2006 Andrea Bittau <a.bittau@cs.ucl.ac.uk> |
| 5 | * |
| 6 | * Changes to meet Linux coding standards, and DCCP infrastructure fixes. |
| 7 | * |
| 8 | * Copyright (c) 2006 Arnaldo Carvalho de Melo <acme@conectiva.com.br> |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or modify |
| 11 | * it under the terms of the GNU General Public License as published by |
| 12 | * the Free Software Foundation; either version 2 of the License, or |
| 13 | * (at your option) any later version. |
| 14 | * |
| 15 | * This program is distributed in the hope that it will be useful, |
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 18 | * GNU General Public License for more details. |
| 19 | * |
| 20 | * You should have received a copy of the GNU General Public License |
| 21 | * along with this program; if not, write to the Free Software |
| 22 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| 23 | */ |
| 24 | |
| 25 | /* |
Gerrit Renker | 0e64e94 | 2006-10-24 16:17:51 -0700 | [diff] [blame] | 26 | * This implementation should follow RFC 4341 |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 27 | */ |
| 28 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 29 | #include "../ccid.h" |
| 30 | #include "../dccp.h" |
| 31 | #include "ccid2.h" |
| 32 | |
Gerrit Renker | 8411671 | 2006-11-20 18:26:03 -0200 | [diff] [blame] | 33 | |
| 34 | #ifdef CONFIG_IP_DCCP_CCID2_DEBUG |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 35 | static int ccid2_debug; |
Gerrit Renker | 8411671 | 2006-11-20 18:26:03 -0200 | [diff] [blame] | 36 | #define ccid2_pr_debug(format, a...) DCCP_PR_DEBUG(ccid2_debug, format, ##a) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 37 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 38 | static void ccid2_hc_tx_check_sanity(const struct ccid2_hc_tx_sock *hctx) |
| 39 | { |
| 40 | int len = 0; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 41 | int pipe = 0; |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 42 | struct ccid2_seq *seqp = hctx->ccid2hctx_seqh; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 43 | |
| 44 | /* there is data in the chain */ |
| 45 | if (seqp != hctx->ccid2hctx_seqt) { |
| 46 | seqp = seqp->ccid2s_prev; |
| 47 | len++; |
| 48 | if (!seqp->ccid2s_acked) |
| 49 | pipe++; |
| 50 | |
| 51 | while (seqp != hctx->ccid2hctx_seqt) { |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 52 | struct ccid2_seq *prev = seqp->ccid2s_prev; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 53 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 54 | len++; |
| 55 | if (!prev->ccid2s_acked) |
| 56 | pipe++; |
| 57 | |
| 58 | /* packets are sent sequentially */ |
Gerrit Renker | 5e28599 | 2007-10-04 14:43:09 -0700 | [diff] [blame] | 59 | BUG_ON(dccp_delta_seqno(seqp->ccid2s_seq, |
| 60 | prev->ccid2s_seq ) >= 0); |
Andrea Bittau | 29651cd | 2006-09-19 13:06:46 -0700 | [diff] [blame] | 61 | BUG_ON(time_before(seqp->ccid2s_sent, |
| 62 | prev->ccid2s_sent)); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 63 | |
| 64 | seqp = prev; |
| 65 | } |
| 66 | } |
| 67 | |
| 68 | BUG_ON(pipe != hctx->ccid2hctx_pipe); |
| 69 | ccid2_pr_debug("len of chain=%d\n", len); |
| 70 | |
| 71 | do { |
| 72 | seqp = seqp->ccid2s_prev; |
| 73 | len++; |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 74 | } while (seqp != hctx->ccid2hctx_seqh); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 75 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 76 | ccid2_pr_debug("total len=%d\n", len); |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 77 | BUG_ON(len != hctx->ccid2hctx_seqbufc * CCID2_SEQBUF_LEN); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 78 | } |
| 79 | #else |
Gerrit Renker | 8411671 | 2006-11-20 18:26:03 -0200 | [diff] [blame] | 80 | #define ccid2_pr_debug(format, a...) |
| 81 | #define ccid2_hc_tx_check_sanity(hctx) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 82 | #endif |
| 83 | |
Gerrit Renker | cd1f7d3 | 2007-10-04 14:41:00 -0700 | [diff] [blame] | 84 | static int ccid2_hc_tx_alloc_seq(struct ccid2_hc_tx_sock *hctx) |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 85 | { |
| 86 | struct ccid2_seq *seqp; |
| 87 | int i; |
| 88 | |
| 89 | /* check if we have space to preserve the pointer to the buffer */ |
| 90 | if (hctx->ccid2hctx_seqbufc >= (sizeof(hctx->ccid2hctx_seqbuf) / |
| 91 | sizeof(struct ccid2_seq*))) |
| 92 | return -ENOMEM; |
| 93 | |
| 94 | /* allocate buffer and initialize linked list */ |
Gerrit Renker | cd1f7d3 | 2007-10-04 14:41:00 -0700 | [diff] [blame] | 95 | seqp = kmalloc(CCID2_SEQBUF_LEN * sizeof(struct ccid2_seq), gfp_any()); |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 96 | if (seqp == NULL) |
| 97 | return -ENOMEM; |
| 98 | |
Gerrit Renker | cd1f7d3 | 2007-10-04 14:41:00 -0700 | [diff] [blame] | 99 | for (i = 0; i < (CCID2_SEQBUF_LEN - 1); i++) { |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 100 | seqp[i].ccid2s_next = &seqp[i + 1]; |
| 101 | seqp[i + 1].ccid2s_prev = &seqp[i]; |
| 102 | } |
Gerrit Renker | cd1f7d3 | 2007-10-04 14:41:00 -0700 | [diff] [blame] | 103 | seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = seqp; |
| 104 | seqp->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1]; |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 105 | |
| 106 | /* This is the first allocation. Initiate the head and tail. */ |
| 107 | if (hctx->ccid2hctx_seqbufc == 0) |
| 108 | hctx->ccid2hctx_seqh = hctx->ccid2hctx_seqt = seqp; |
| 109 | else { |
| 110 | /* link the existing list with the one we just created */ |
| 111 | hctx->ccid2hctx_seqh->ccid2s_next = seqp; |
| 112 | seqp->ccid2s_prev = hctx->ccid2hctx_seqh; |
| 113 | |
Gerrit Renker | cd1f7d3 | 2007-10-04 14:41:00 -0700 | [diff] [blame] | 114 | hctx->ccid2hctx_seqt->ccid2s_prev = &seqp[CCID2_SEQBUF_LEN - 1]; |
| 115 | seqp[CCID2_SEQBUF_LEN - 1].ccid2s_next = hctx->ccid2hctx_seqt; |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 116 | } |
| 117 | |
| 118 | /* store the original pointer to the buffer so we can free it */ |
| 119 | hctx->ccid2hctx_seqbuf[hctx->ccid2hctx_seqbufc] = seqp; |
| 120 | hctx->ccid2hctx_seqbufc++; |
| 121 | |
| 122 | return 0; |
| 123 | } |
| 124 | |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 125 | static int ccid2_hc_tx_send_packet(struct sock *sk, struct sk_buff *skb) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 126 | { |
Gerrit Renker | 6c58324 | 2007-10-04 14:42:19 -0700 | [diff] [blame] | 127 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 128 | |
| 129 | ccid2_pr_debug("pipe=%d cwnd=%d\n", hctx->ccid2hctx_pipe, |
| 130 | hctx->ccid2hctx_cwnd); |
| 131 | |
| 132 | if (hctx->ccid2hctx_pipe < hctx->ccid2hctx_cwnd) { |
| 133 | /* OK we can send... make sure previous packet was sent off */ |
| 134 | if (!hctx->ccid2hctx_sendwait) { |
| 135 | hctx->ccid2hctx_sendwait = 1; |
| 136 | return 0; |
| 137 | } |
| 138 | } |
| 139 | |
Andrea Bittau | 446dec3 | 2006-09-19 13:10:11 -0700 | [diff] [blame] | 140 | return 1; /* XXX CCID should dequeue when ready instead of polling */ |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 141 | } |
| 142 | |
Gerrit Renker | df054e1 | 2007-11-24 21:32:53 -0200 | [diff] [blame] | 143 | static void ccid2_change_l_ack_ratio(struct sock *sk, u32 val) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 144 | { |
| 145 | struct dccp_sock *dp = dccp_sk(sk); |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 146 | u32 max_ratio = DIV_ROUND_UP(ccid2_hc_tx_sk(sk)->ccid2hctx_cwnd, 2); |
| 147 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 148 | /* |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 149 | * Ensure that Ack Ratio does not exceed ceil(cwnd/2), which is (2) from |
| 150 | * RFC 4341, 6.1.2. We ignore the statement that Ack Ratio 2 is always |
| 151 | * acceptable since this causes starvation/deadlock whenever cwnd < 2. |
| 152 | * The same problem arises when Ack Ratio is 0 (ie. Ack Ratio disabled). |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 153 | */ |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 154 | if (val == 0 || val > max_ratio) { |
| 155 | DCCP_WARN("Limiting Ack Ratio (%u) to %u\n", val, max_ratio); |
| 156 | val = max_ratio; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 157 | } |
Gerrit Renker | df054e1 | 2007-11-24 21:32:53 -0200 | [diff] [blame] | 158 | if (val > 0xFFFF) /* RFC 4340, 11.3 */ |
| 159 | val = 0xFFFF; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 160 | |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 161 | if (val == dp->dccps_l_ack_ratio) |
| 162 | return; |
| 163 | |
Gerrit Renker | df054e1 | 2007-11-24 21:32:53 -0200 | [diff] [blame] | 164 | ccid2_pr_debug("changing local ack ratio to %u\n", val); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 165 | dp->dccps_l_ack_ratio = val; |
| 166 | } |
| 167 | |
Gerrit Renker | ee196c2 | 2007-10-04 14:41:55 -0700 | [diff] [blame] | 168 | static void ccid2_change_cwnd(struct ccid2_hc_tx_sock *hctx, u32 val) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 169 | { |
Gerrit Renker | ee196c2 | 2007-10-04 14:41:55 -0700 | [diff] [blame] | 170 | hctx->ccid2hctx_cwnd = val? : 1; |
| 171 | ccid2_pr_debug("changed cwnd to %u\n", hctx->ccid2hctx_cwnd); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 172 | } |
| 173 | |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 174 | static void ccid2_change_srtt(struct ccid2_hc_tx_sock *hctx, long val) |
| 175 | { |
| 176 | ccid2_pr_debug("change SRTT to %ld\n", val); |
| 177 | hctx->ccid2hctx_srtt = val; |
| 178 | } |
| 179 | |
| 180 | static void ccid2_change_pipe(struct ccid2_hc_tx_sock *hctx, long val) |
| 181 | { |
| 182 | hctx->ccid2hctx_pipe = val; |
| 183 | } |
| 184 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 185 | static void ccid2_start_rto_timer(struct sock *sk); |
| 186 | |
| 187 | static void ccid2_hc_tx_rto_expire(unsigned long data) |
| 188 | { |
| 189 | struct sock *sk = (struct sock *)data; |
| 190 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 191 | long s; |
| 192 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 193 | bh_lock_sock(sk); |
| 194 | if (sock_owned_by_user(sk)) { |
| 195 | sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer, |
| 196 | jiffies + HZ / 5); |
| 197 | goto out; |
| 198 | } |
| 199 | |
| 200 | ccid2_pr_debug("RTO_EXPIRE\n"); |
| 201 | |
| 202 | ccid2_hc_tx_check_sanity(hctx); |
| 203 | |
| 204 | /* back-off timer */ |
| 205 | hctx->ccid2hctx_rto <<= 1; |
| 206 | |
| 207 | s = hctx->ccid2hctx_rto / HZ; |
| 208 | if (s > 60) |
| 209 | hctx->ccid2hctx_rto = 60 * HZ; |
| 210 | |
| 211 | ccid2_start_rto_timer(sk); |
| 212 | |
| 213 | /* adjust pipe, cwnd etc */ |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 214 | ccid2_change_pipe(hctx, 0); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 215 | hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd >> 1; |
| 216 | if (hctx->ccid2hctx_ssthresh < 2) |
| 217 | hctx->ccid2hctx_ssthresh = 2; |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 218 | ccid2_change_cwnd(hctx, 1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 219 | |
| 220 | /* clear state about stuff we sent */ |
| 221 | hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqh; |
| 222 | hctx->ccid2hctx_ssacks = 0; |
| 223 | hctx->ccid2hctx_acks = 0; |
| 224 | hctx->ccid2hctx_sent = 0; |
| 225 | |
| 226 | /* clear ack ratio state. */ |
| 227 | hctx->ccid2hctx_arsent = 0; |
| 228 | hctx->ccid2hctx_ackloss = 0; |
| 229 | hctx->ccid2hctx_rpseq = 0; |
| 230 | hctx->ccid2hctx_rpdupack = -1; |
| 231 | ccid2_change_l_ack_ratio(sk, 1); |
| 232 | ccid2_hc_tx_check_sanity(hctx); |
| 233 | out: |
| 234 | bh_unlock_sock(sk); |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 235 | sock_put(sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 236 | } |
| 237 | |
| 238 | static void ccid2_start_rto_timer(struct sock *sk) |
| 239 | { |
| 240 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 241 | |
| 242 | ccid2_pr_debug("setting RTO timeout=%ld\n", hctx->ccid2hctx_rto); |
| 243 | |
| 244 | BUG_ON(timer_pending(&hctx->ccid2hctx_rtotimer)); |
| 245 | sk_reset_timer(sk, &hctx->ccid2hctx_rtotimer, |
| 246 | jiffies + hctx->ccid2hctx_rto); |
| 247 | } |
| 248 | |
Gerrit Renker | 6b57c93 | 2006-11-28 19:55:06 -0200 | [diff] [blame] | 249 | static void ccid2_hc_tx_packet_sent(struct sock *sk, int more, unsigned int len) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 250 | { |
| 251 | struct dccp_sock *dp = dccp_sk(sk); |
| 252 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 253 | struct ccid2_seq *next; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 254 | u64 seq; |
| 255 | |
| 256 | ccid2_hc_tx_check_sanity(hctx); |
| 257 | |
| 258 | BUG_ON(!hctx->ccid2hctx_sendwait); |
| 259 | hctx->ccid2hctx_sendwait = 0; |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 260 | ccid2_change_pipe(hctx, hctx->ccid2hctx_pipe + 1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 261 | BUG_ON(hctx->ccid2hctx_pipe < 0); |
| 262 | |
| 263 | /* There is an issue. What if another packet is sent between |
| 264 | * packet_send() and packet_sent(). Then the sequence number would be |
| 265 | * wrong. |
| 266 | * -sorbo. |
| 267 | */ |
| 268 | seq = dp->dccps_gss; |
| 269 | |
| 270 | hctx->ccid2hctx_seqh->ccid2s_seq = seq; |
| 271 | hctx->ccid2hctx_seqh->ccid2s_acked = 0; |
| 272 | hctx->ccid2hctx_seqh->ccid2s_sent = jiffies; |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 273 | |
| 274 | next = hctx->ccid2hctx_seqh->ccid2s_next; |
| 275 | /* check if we need to alloc more space */ |
| 276 | if (next == hctx->ccid2hctx_seqt) { |
Gerrit Renker | 7d9e893 | 2007-10-04 14:41:26 -0700 | [diff] [blame] | 277 | if (ccid2_hc_tx_alloc_seq(hctx)) { |
| 278 | DCCP_CRIT("packet history - out of memory!"); |
| 279 | /* FIXME: find a more graceful way to bail out */ |
| 280 | return; |
| 281 | } |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 282 | next = hctx->ccid2hctx_seqh->ccid2s_next; |
| 283 | BUG_ON(next == hctx->ccid2hctx_seqt); |
| 284 | } |
| 285 | hctx->ccid2hctx_seqh = next; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 286 | |
| 287 | ccid2_pr_debug("cwnd=%d pipe=%d\n", hctx->ccid2hctx_cwnd, |
| 288 | hctx->ccid2hctx_pipe); |
| 289 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 290 | hctx->ccid2hctx_sent++; |
| 291 | |
| 292 | /* Ack Ratio. Need to maintain a concept of how many windows we sent */ |
| 293 | hctx->ccid2hctx_arsent++; |
| 294 | /* We had an ack loss in this window... */ |
| 295 | if (hctx->ccid2hctx_ackloss) { |
| 296 | if (hctx->ccid2hctx_arsent >= hctx->ccid2hctx_cwnd) { |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 297 | hctx->ccid2hctx_arsent = 0; |
| 298 | hctx->ccid2hctx_ackloss = 0; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 299 | } |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 300 | } else { |
| 301 | /* No acks lost up to now... */ |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 302 | /* decrease ack ratio if enough packets were sent */ |
| 303 | if (dp->dccps_l_ack_ratio > 1) { |
| 304 | /* XXX don't calculate denominator each time */ |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 305 | int denom = dp->dccps_l_ack_ratio * dp->dccps_l_ack_ratio - |
| 306 | dp->dccps_l_ack_ratio; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 307 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 308 | denom = hctx->ccid2hctx_cwnd * hctx->ccid2hctx_cwnd / denom; |
| 309 | |
| 310 | if (hctx->ccid2hctx_arsent >= denom) { |
| 311 | ccid2_change_l_ack_ratio(sk, dp->dccps_l_ack_ratio - 1); |
| 312 | hctx->ccid2hctx_arsent = 0; |
| 313 | } |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 314 | } else { |
| 315 | /* we can't increase ack ratio further [1] */ |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 316 | hctx->ccid2hctx_arsent = 0; /* or maybe set it to cwnd*/ |
| 317 | } |
| 318 | } |
| 319 | |
| 320 | /* setup RTO timer */ |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 321 | if (!timer_pending(&hctx->ccid2hctx_rtotimer)) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 322 | ccid2_start_rto_timer(sk); |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 323 | |
Andrea Bittau | 8d424f6 | 2006-09-19 13:12:44 -0700 | [diff] [blame] | 324 | #ifdef CONFIG_IP_DCCP_CCID2_DEBUG |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 325 | ccid2_pr_debug("pipe=%d\n", hctx->ccid2hctx_pipe); |
Randy Dunlap | 234af48 | 2006-10-29 16:03:30 -0800 | [diff] [blame] | 326 | ccid2_pr_debug("Sent: seq=%llu\n", (unsigned long long)seq); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 327 | do { |
| 328 | struct ccid2_seq *seqp = hctx->ccid2hctx_seqt; |
| 329 | |
| 330 | while (seqp != hctx->ccid2hctx_seqh) { |
| 331 | ccid2_pr_debug("out seq=%llu acked=%d time=%lu\n", |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 332 | (unsigned long long)seqp->ccid2s_seq, |
Randy Dunlap | 234af48 | 2006-10-29 16:03:30 -0800 | [diff] [blame] | 333 | seqp->ccid2s_acked, seqp->ccid2s_sent); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 334 | seqp = seqp->ccid2s_next; |
| 335 | } |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 336 | } while (0); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 337 | ccid2_pr_debug("=========\n"); |
| 338 | ccid2_hc_tx_check_sanity(hctx); |
| 339 | #endif |
| 340 | } |
| 341 | |
| 342 | /* XXX Lame code duplication! |
| 343 | * returns -1 if none was found. |
| 344 | * else returns the next offset to use in the function call. |
| 345 | */ |
| 346 | static int ccid2_ackvector(struct sock *sk, struct sk_buff *skb, int offset, |
| 347 | unsigned char **vec, unsigned char *veclen) |
| 348 | { |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 349 | const struct dccp_hdr *dh = dccp_hdr(skb); |
| 350 | unsigned char *options = (unsigned char *)dh + dccp_hdr_len(skb); |
| 351 | unsigned char *opt_ptr; |
| 352 | const unsigned char *opt_end = (unsigned char *)dh + |
| 353 | (dh->dccph_doff * 4); |
| 354 | unsigned char opt, len; |
| 355 | unsigned char *value; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 356 | |
| 357 | BUG_ON(offset < 0); |
| 358 | options += offset; |
| 359 | opt_ptr = options; |
| 360 | if (opt_ptr >= opt_end) |
| 361 | return -1; |
| 362 | |
| 363 | while (opt_ptr != opt_end) { |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 364 | opt = *opt_ptr++; |
| 365 | len = 0; |
| 366 | value = NULL; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 367 | |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 368 | /* Check if this isn't a single byte option */ |
| 369 | if (opt > DCCPO_MAX_RESERVED) { |
| 370 | if (opt_ptr == opt_end) |
| 371 | goto out_invalid_option; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 372 | |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 373 | len = *opt_ptr++; |
| 374 | if (len < 3) |
| 375 | goto out_invalid_option; |
| 376 | /* |
| 377 | * Remove the type and len fields, leaving |
| 378 | * just the value size |
| 379 | */ |
| 380 | len -= 2; |
| 381 | value = opt_ptr; |
| 382 | opt_ptr += len; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 383 | |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 384 | if (opt_ptr > opt_end) |
| 385 | goto out_invalid_option; |
| 386 | } |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 387 | |
| 388 | switch (opt) { |
| 389 | case DCCPO_ACK_VECTOR_0: |
| 390 | case DCCPO_ACK_VECTOR_1: |
| 391 | *vec = value; |
| 392 | *veclen = len; |
| 393 | return offset + (opt_ptr - options); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 394 | } |
| 395 | } |
| 396 | |
| 397 | return -1; |
| 398 | |
| 399 | out_invalid_option: |
Gerrit Renker | 59348b1 | 2006-11-20 18:39:23 -0200 | [diff] [blame] | 400 | DCCP_BUG("Invalid option - this should not happen (previous parsing)!"); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 401 | return -1; |
| 402 | } |
| 403 | |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 404 | static void ccid2_hc_tx_kill_rto_timer(struct sock *sk) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 405 | { |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 406 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 407 | |
| 408 | sk_stop_timer(sk, &hctx->ccid2hctx_rtotimer); |
| 409 | ccid2_pr_debug("deleted RTO timer\n"); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 410 | } |
| 411 | |
| 412 | static inline void ccid2_new_ack(struct sock *sk, |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 413 | struct ccid2_seq *seqp, |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 414 | unsigned int *maxincr) |
| 415 | { |
| 416 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 417 | |
| 418 | /* slow start */ |
| 419 | if (hctx->ccid2hctx_cwnd < hctx->ccid2hctx_ssthresh) { |
| 420 | hctx->ccid2hctx_acks = 0; |
| 421 | |
| 422 | /* We can increase cwnd at most maxincr [ack_ratio/2] */ |
| 423 | if (*maxincr) { |
| 424 | /* increase every 2 acks */ |
| 425 | hctx->ccid2hctx_ssacks++; |
| 426 | if (hctx->ccid2hctx_ssacks == 2) { |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 427 | ccid2_change_cwnd(hctx, hctx->ccid2hctx_cwnd+1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 428 | hctx->ccid2hctx_ssacks = 0; |
| 429 | *maxincr = *maxincr - 1; |
| 430 | } |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 431 | } else { |
| 432 | /* increased cwnd enough for this single ack */ |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 433 | hctx->ccid2hctx_ssacks = 0; |
| 434 | } |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 435 | } else { |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 436 | hctx->ccid2hctx_ssacks = 0; |
| 437 | hctx->ccid2hctx_acks++; |
| 438 | |
| 439 | if (hctx->ccid2hctx_acks >= hctx->ccid2hctx_cwnd) { |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 440 | ccid2_change_cwnd(hctx, hctx->ccid2hctx_cwnd + 1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 441 | hctx->ccid2hctx_acks = 0; |
| 442 | } |
| 443 | } |
| 444 | |
| 445 | /* update RTO */ |
| 446 | if (hctx->ccid2hctx_srtt == -1 || |
Andrea Bittau | 29651cd | 2006-09-19 13:06:46 -0700 | [diff] [blame] | 447 | time_after(jiffies, hctx->ccid2hctx_lastrtt + hctx->ccid2hctx_srtt)) { |
| 448 | unsigned long r = (long)jiffies - (long)seqp->ccid2s_sent; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 449 | int s; |
| 450 | |
| 451 | /* first measurement */ |
| 452 | if (hctx->ccid2hctx_srtt == -1) { |
| 453 | ccid2_pr_debug("R: %lu Time=%lu seq=%llu\n", |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 454 | r, jiffies, |
Randy Dunlap | 234af48 | 2006-10-29 16:03:30 -0800 | [diff] [blame] | 455 | (unsigned long long)seqp->ccid2s_seq); |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 456 | ccid2_change_srtt(hctx, r); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 457 | hctx->ccid2hctx_rttvar = r >> 1; |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 458 | } else { |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 459 | /* RTTVAR */ |
| 460 | long tmp = hctx->ccid2hctx_srtt - r; |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 461 | long srtt; |
| 462 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 463 | if (tmp < 0) |
| 464 | tmp *= -1; |
| 465 | |
| 466 | tmp >>= 2; |
| 467 | hctx->ccid2hctx_rttvar *= 3; |
| 468 | hctx->ccid2hctx_rttvar >>= 2; |
| 469 | hctx->ccid2hctx_rttvar += tmp; |
| 470 | |
| 471 | /* SRTT */ |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 472 | srtt = hctx->ccid2hctx_srtt; |
| 473 | srtt *= 7; |
| 474 | srtt >>= 3; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 475 | tmp = r >> 3; |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 476 | srtt += tmp; |
| 477 | ccid2_change_srtt(hctx, srtt); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 478 | } |
| 479 | s = hctx->ccid2hctx_rttvar << 2; |
| 480 | /* clock granularity is 1 when based on jiffies */ |
| 481 | if (!s) |
| 482 | s = 1; |
| 483 | hctx->ccid2hctx_rto = hctx->ccid2hctx_srtt + s; |
| 484 | |
| 485 | /* must be at least a second */ |
| 486 | s = hctx->ccid2hctx_rto / HZ; |
| 487 | /* DCCP doesn't require this [but I like it cuz my code sux] */ |
| 488 | #if 1 |
| 489 | if (s < 1) |
| 490 | hctx->ccid2hctx_rto = HZ; |
| 491 | #endif |
| 492 | /* max 60 seconds */ |
| 493 | if (s > 60) |
| 494 | hctx->ccid2hctx_rto = HZ * 60; |
| 495 | |
| 496 | hctx->ccid2hctx_lastrtt = jiffies; |
| 497 | |
| 498 | ccid2_pr_debug("srtt: %ld rttvar: %ld rto: %ld (HZ=%d) R=%lu\n", |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 499 | hctx->ccid2hctx_srtt, hctx->ccid2hctx_rttvar, |
| 500 | hctx->ccid2hctx_rto, HZ, r); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 501 | hctx->ccid2hctx_sent = 0; |
| 502 | } |
| 503 | |
| 504 | /* we got a new ack, so re-start RTO timer */ |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 505 | ccid2_hc_tx_kill_rto_timer(sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 506 | ccid2_start_rto_timer(sk); |
| 507 | } |
| 508 | |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 509 | static void ccid2_hc_tx_dec_pipe(struct sock *sk) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 510 | { |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 511 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 512 | |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 513 | ccid2_change_pipe(hctx, hctx->ccid2hctx_pipe-1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 514 | BUG_ON(hctx->ccid2hctx_pipe < 0); |
| 515 | |
| 516 | if (hctx->ccid2hctx_pipe == 0) |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 517 | ccid2_hc_tx_kill_rto_timer(sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 518 | } |
| 519 | |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 520 | static void ccid2_congestion_event(struct sock *sk, struct ccid2_seq *seqp) |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 521 | { |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 522 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 523 | |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 524 | if (time_before(seqp->ccid2s_sent, hctx->ccid2hctx_last_cong)) { |
| 525 | ccid2_pr_debug("Multiple losses in an RTT---treating as one\n"); |
| 526 | return; |
| 527 | } |
| 528 | |
| 529 | hctx->ccid2hctx_last_cong = jiffies; |
| 530 | |
| 531 | ccid2_change_cwnd(hctx, hctx->ccid2hctx_cwnd >> 1); |
| 532 | hctx->ccid2hctx_ssthresh = hctx->ccid2hctx_cwnd; |
| 533 | if (hctx->ccid2hctx_ssthresh < 2) |
| 534 | hctx->ccid2hctx_ssthresh = 2; |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 535 | |
| 536 | /* Avoid spurious timeouts resulting from Ack Ratio > cwnd */ |
| 537 | if (dccp_sk(sk)->dccps_l_ack_ratio > hctx->ccid2hctx_cwnd) |
| 538 | ccid2_change_l_ack_ratio(sk, hctx->ccid2hctx_cwnd); |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 539 | } |
| 540 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 541 | static void ccid2_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 542 | { |
| 543 | struct dccp_sock *dp = dccp_sk(sk); |
| 544 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
| 545 | u64 ackno, seqno; |
| 546 | struct ccid2_seq *seqp; |
| 547 | unsigned char *vector; |
| 548 | unsigned char veclen; |
| 549 | int offset = 0; |
| 550 | int done = 0; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 551 | unsigned int maxincr = 0; |
| 552 | |
| 553 | ccid2_hc_tx_check_sanity(hctx); |
| 554 | /* check reverse path congestion */ |
| 555 | seqno = DCCP_SKB_CB(skb)->dccpd_seq; |
| 556 | |
| 557 | /* XXX this whole "algorithm" is broken. Need to fix it to keep track |
| 558 | * of the seqnos of the dupacks so that rpseq and rpdupack are correct |
| 559 | * -sorbo. |
| 560 | */ |
| 561 | /* need to bootstrap */ |
| 562 | if (hctx->ccid2hctx_rpdupack == -1) { |
| 563 | hctx->ccid2hctx_rpdupack = 0; |
| 564 | hctx->ccid2hctx_rpseq = seqno; |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 565 | } else { |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 566 | /* check if packet is consecutive */ |
Gerrit Renker | 5e28599 | 2007-10-04 14:43:09 -0700 | [diff] [blame] | 567 | if (dccp_delta_seqno(hctx->ccid2hctx_rpseq, seqno) == 1) |
| 568 | hctx->ccid2hctx_rpseq = seqno; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 569 | /* it's a later packet */ |
| 570 | else if (after48(seqno, hctx->ccid2hctx_rpseq)) { |
| 571 | hctx->ccid2hctx_rpdupack++; |
| 572 | |
| 573 | /* check if we got enough dupacks */ |
| 574 | if (hctx->ccid2hctx_rpdupack >= |
| 575 | hctx->ccid2hctx_numdupack) { |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 576 | hctx->ccid2hctx_rpdupack = -1; /* XXX lame */ |
| 577 | hctx->ccid2hctx_rpseq = 0; |
| 578 | |
Gerrit Renker | df054e1 | 2007-11-24 21:32:53 -0200 | [diff] [blame] | 579 | ccid2_change_l_ack_ratio(sk, 2 * dp->dccps_l_ack_ratio); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 580 | } |
| 581 | } |
| 582 | } |
| 583 | |
| 584 | /* check forward path congestion */ |
| 585 | /* still didn't send out new data packets */ |
| 586 | if (hctx->ccid2hctx_seqh == hctx->ccid2hctx_seqt) |
| 587 | return; |
| 588 | |
| 589 | switch (DCCP_SKB_CB(skb)->dccpd_type) { |
| 590 | case DCCP_PKT_ACK: |
| 591 | case DCCP_PKT_DATAACK: |
| 592 | break; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 593 | default: |
| 594 | return; |
| 595 | } |
| 596 | |
| 597 | ackno = DCCP_SKB_CB(skb)->dccpd_ack_seq; |
Andrea Bittau | 32aac18 | 2006-11-16 14:28:40 -0200 | [diff] [blame] | 598 | if (after48(ackno, hctx->ccid2hctx_high_ack)) |
| 599 | hctx->ccid2hctx_high_ack = ackno; |
| 600 | |
| 601 | seqp = hctx->ccid2hctx_seqt; |
| 602 | while (before48(seqp->ccid2s_seq, ackno)) { |
| 603 | seqp = seqp->ccid2s_next; |
| 604 | if (seqp == hctx->ccid2hctx_seqh) { |
| 605 | seqp = hctx->ccid2hctx_seqh->ccid2s_prev; |
| 606 | break; |
| 607 | } |
| 608 | } |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 609 | |
| 610 | /* If in slow-start, cwnd can increase at most Ack Ratio / 2 packets for |
| 611 | * this single ack. I round up. |
| 612 | * -sorbo. |
| 613 | */ |
| 614 | maxincr = dp->dccps_l_ack_ratio >> 1; |
| 615 | maxincr++; |
| 616 | |
| 617 | /* go through all ack vectors */ |
| 618 | while ((offset = ccid2_ackvector(sk, skb, offset, |
| 619 | &vector, &veclen)) != -1) { |
| 620 | /* go through this ack vector */ |
| 621 | while (veclen--) { |
| 622 | const u8 rl = *vector & DCCP_ACKVEC_LEN_MASK; |
Gerrit Renker | cfbbeab | 2007-11-24 20:43:59 -0200 | [diff] [blame] | 623 | u64 ackno_end_rl = SUB48(ackno, rl); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 624 | |
Randy Dunlap | 234af48 | 2006-10-29 16:03:30 -0800 | [diff] [blame] | 625 | ccid2_pr_debug("ackvec start:%llu end:%llu\n", |
| 626 | (unsigned long long)ackno, |
| 627 | (unsigned long long)ackno_end_rl); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 628 | /* if the seqno we are analyzing is larger than the |
| 629 | * current ackno, then move towards the tail of our |
| 630 | * seqnos. |
| 631 | */ |
| 632 | while (after48(seqp->ccid2s_seq, ackno)) { |
| 633 | if (seqp == hctx->ccid2hctx_seqt) { |
| 634 | done = 1; |
| 635 | break; |
| 636 | } |
| 637 | seqp = seqp->ccid2s_prev; |
| 638 | } |
| 639 | if (done) |
| 640 | break; |
| 641 | |
| 642 | /* check all seqnos in the range of the vector |
| 643 | * run length |
| 644 | */ |
| 645 | while (between48(seqp->ccid2s_seq,ackno_end_rl,ackno)) { |
Andrea Bittau | 8e27e46 | 2006-09-19 13:05:35 -0700 | [diff] [blame] | 646 | const u8 state = *vector & |
| 647 | DCCP_ACKVEC_STATE_MASK; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 648 | |
| 649 | /* new packet received or marked */ |
| 650 | if (state != DCCP_ACKVEC_STATE_NOT_RECEIVED && |
| 651 | !seqp->ccid2s_acked) { |
Arnaldo Carvalho de Melo | 8109b02 | 2006-12-10 16:01:18 -0200 | [diff] [blame] | 652 | if (state == |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 653 | DCCP_ACKVEC_STATE_ECN_MARKED) { |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 654 | ccid2_congestion_event(sk, |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 655 | seqp); |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 656 | } else |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 657 | ccid2_new_ack(sk, seqp, |
| 658 | &maxincr); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 659 | |
| 660 | seqp->ccid2s_acked = 1; |
| 661 | ccid2_pr_debug("Got ack for %llu\n", |
Randy Dunlap | 234af48 | 2006-10-29 16:03:30 -0800 | [diff] [blame] | 662 | (unsigned long long)seqp->ccid2s_seq); |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 663 | ccid2_hc_tx_dec_pipe(sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 664 | } |
| 665 | if (seqp == hctx->ccid2hctx_seqt) { |
| 666 | done = 1; |
| 667 | break; |
| 668 | } |
Gerrit Renker | 3de5489 | 2007-11-24 20:37:48 -0200 | [diff] [blame] | 669 | seqp = seqp->ccid2s_prev; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 670 | } |
| 671 | if (done) |
| 672 | break; |
| 673 | |
Gerrit Renker | cfbbeab | 2007-11-24 20:43:59 -0200 | [diff] [blame] | 674 | ackno = SUB48(ackno_end_rl, 1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 675 | vector++; |
| 676 | } |
| 677 | if (done) |
| 678 | break; |
| 679 | } |
| 680 | |
| 681 | /* The state about what is acked should be correct now |
| 682 | * Check for NUMDUPACK |
| 683 | */ |
Andrea Bittau | 32aac18 | 2006-11-16 14:28:40 -0200 | [diff] [blame] | 684 | seqp = hctx->ccid2hctx_seqt; |
| 685 | while (before48(seqp->ccid2s_seq, hctx->ccid2hctx_high_ack)) { |
| 686 | seqp = seqp->ccid2s_next; |
| 687 | if (seqp == hctx->ccid2hctx_seqh) { |
| 688 | seqp = hctx->ccid2hctx_seqh->ccid2s_prev; |
| 689 | break; |
| 690 | } |
| 691 | } |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 692 | done = 0; |
| 693 | while (1) { |
| 694 | if (seqp->ccid2s_acked) { |
| 695 | done++; |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 696 | if (done == hctx->ccid2hctx_numdupack) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 697 | break; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 698 | } |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 699 | if (seqp == hctx->ccid2hctx_seqt) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 700 | break; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 701 | seqp = seqp->ccid2s_prev; |
| 702 | } |
| 703 | |
| 704 | /* If there are at least 3 acknowledgements, anything unacknowledged |
| 705 | * below the last sequence number is considered lost |
| 706 | */ |
| 707 | if (done == hctx->ccid2hctx_numdupack) { |
| 708 | struct ccid2_seq *last_acked = seqp; |
| 709 | |
| 710 | /* check for lost packets */ |
| 711 | while (1) { |
| 712 | if (!seqp->ccid2s_acked) { |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 713 | ccid2_pr_debug("Packet lost: %llu\n", |
Randy Dunlap | 234af48 | 2006-10-29 16:03:30 -0800 | [diff] [blame] | 714 | (unsigned long long)seqp->ccid2s_seq); |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 715 | /* XXX need to traverse from tail -> head in |
| 716 | * order to detect multiple congestion events in |
| 717 | * one ack vector. |
| 718 | */ |
Gerrit Renker | d50ad16 | 2007-11-24 21:40:24 -0200 | [diff] [blame] | 719 | ccid2_congestion_event(sk, seqp); |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 720 | ccid2_hc_tx_dec_pipe(sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 721 | } |
| 722 | if (seqp == hctx->ccid2hctx_seqt) |
| 723 | break; |
| 724 | seqp = seqp->ccid2s_prev; |
| 725 | } |
| 726 | |
| 727 | hctx->ccid2hctx_seqt = last_acked; |
| 728 | } |
| 729 | |
| 730 | /* trim acked packets in tail */ |
| 731 | while (hctx->ccid2hctx_seqt != hctx->ccid2hctx_seqh) { |
| 732 | if (!hctx->ccid2hctx_seqt->ccid2s_acked) |
| 733 | break; |
| 734 | |
| 735 | hctx->ccid2hctx_seqt = hctx->ccid2hctx_seqt->ccid2s_next; |
| 736 | } |
| 737 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 738 | ccid2_hc_tx_check_sanity(hctx); |
| 739 | } |
| 740 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 741 | static int ccid2_hc_tx_init(struct ccid *ccid, struct sock *sk) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 742 | { |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 743 | struct ccid2_hc_tx_sock *hctx = ccid_priv(ccid); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 744 | |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 745 | ccid2_change_cwnd(hctx, 1); |
Andrea Bittau | d458c25 | 2006-09-19 13:07:20 -0700 | [diff] [blame] | 746 | /* Initialize ssthresh to infinity. This means that we will exit the |
| 747 | * initial slow-start after the first packet loss. This is what we |
| 748 | * want. |
| 749 | */ |
| 750 | hctx->ccid2hctx_ssthresh = ~0; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 751 | hctx->ccid2hctx_numdupack = 3; |
| 752 | |
| 753 | /* XXX init ~ to window size... */ |
Gerrit Renker | cd1f7d3 | 2007-10-04 14:41:00 -0700 | [diff] [blame] | 754 | if (ccid2_hc_tx_alloc_seq(hctx)) |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 755 | return -ENOMEM; |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 756 | |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 757 | hctx->ccid2hctx_rto = 3 * HZ; |
Andrea Bittau | 593f16a | 2006-09-19 13:15:33 -0700 | [diff] [blame] | 758 | ccid2_change_srtt(hctx, -1); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 759 | hctx->ccid2hctx_rttvar = -1; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 760 | hctx->ccid2hctx_rpdupack = -1; |
Andrea Bittau | 374bcf3 | 2006-09-19 13:14:43 -0700 | [diff] [blame] | 761 | hctx->ccid2hctx_last_cong = jiffies; |
Pavel Emelyanov | b24b8a2 | 2008-01-23 21:20:07 -0800 | [diff] [blame] | 762 | setup_timer(&hctx->ccid2hctx_rtotimer, ccid2_hc_tx_rto_expire, |
| 763 | (unsigned long)sk); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 764 | |
| 765 | ccid2_hc_tx_check_sanity(hctx); |
| 766 | return 0; |
| 767 | } |
| 768 | |
| 769 | static void ccid2_hc_tx_exit(struct sock *sk) |
| 770 | { |
YOSHIFUJI Hideaki | c9eaf17 | 2007-02-09 23:24:38 +0900 | [diff] [blame] | 771 | struct ccid2_hc_tx_sock *hctx = ccid2_hc_tx_sk(sk); |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 772 | int i; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 773 | |
Andrea Bittau | 77ff72d | 2006-03-20 17:57:52 -0800 | [diff] [blame] | 774 | ccid2_hc_tx_kill_rto_timer(sk); |
Andrea Bittau | 07978aa | 2006-09-19 13:13:37 -0700 | [diff] [blame] | 775 | |
| 776 | for (i = 0; i < hctx->ccid2hctx_seqbufc; i++) |
| 777 | kfree(hctx->ccid2hctx_seqbuf[i]); |
| 778 | hctx->ccid2hctx_seqbufc = 0; |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 779 | } |
| 780 | |
| 781 | static void ccid2_hc_rx_packet_recv(struct sock *sk, struct sk_buff *skb) |
| 782 | { |
| 783 | const struct dccp_sock *dp = dccp_sk(sk); |
| 784 | struct ccid2_hc_rx_sock *hcrx = ccid2_hc_rx_sk(sk); |
| 785 | |
| 786 | switch (DCCP_SKB_CB(skb)->dccpd_type) { |
| 787 | case DCCP_PKT_DATA: |
| 788 | case DCCP_PKT_DATAACK: |
| 789 | hcrx->ccid2hcrx_data++; |
| 790 | if (hcrx->ccid2hcrx_data >= dp->dccps_r_ack_ratio) { |
| 791 | dccp_send_ack(sk); |
| 792 | hcrx->ccid2hcrx_data = 0; |
| 793 | } |
| 794 | break; |
| 795 | } |
| 796 | } |
| 797 | |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 798 | static struct ccid_operations ccid2 = { |
Ian McDonald | 3dd9a7c | 2006-09-22 14:26:44 +1200 | [diff] [blame] | 799 | .ccid_id = DCCPC_CCID2, |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 800 | .ccid_name = "ccid2", |
| 801 | .ccid_owner = THIS_MODULE, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 802 | .ccid_hc_tx_obj_size = sizeof(struct ccid2_hc_tx_sock), |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 803 | .ccid_hc_tx_init = ccid2_hc_tx_init, |
| 804 | .ccid_hc_tx_exit = ccid2_hc_tx_exit, |
| 805 | .ccid_hc_tx_send_packet = ccid2_hc_tx_send_packet, |
| 806 | .ccid_hc_tx_packet_sent = ccid2_hc_tx_packet_sent, |
| 807 | .ccid_hc_tx_packet_recv = ccid2_hc_tx_packet_recv, |
Arnaldo Carvalho de Melo | 91f0ebf | 2006-03-20 19:21:44 -0800 | [diff] [blame] | 808 | .ccid_hc_rx_obj_size = sizeof(struct ccid2_hc_rx_sock), |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 809 | .ccid_hc_rx_packet_recv = ccid2_hc_rx_packet_recv, |
| 810 | }; |
| 811 | |
Gerrit Renker | 8411671 | 2006-11-20 18:26:03 -0200 | [diff] [blame] | 812 | #ifdef CONFIG_IP_DCCP_CCID2_DEBUG |
Gerrit Renker | 042d18f | 2007-10-04 14:39:53 -0700 | [diff] [blame] | 813 | module_param(ccid2_debug, bool, 0444); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 814 | MODULE_PARM_DESC(ccid2_debug, "Enable debug messages"); |
Gerrit Renker | 8411671 | 2006-11-20 18:26:03 -0200 | [diff] [blame] | 815 | #endif |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 816 | |
| 817 | static __init int ccid2_module_init(void) |
| 818 | { |
| 819 | return ccid_register(&ccid2); |
| 820 | } |
| 821 | module_init(ccid2_module_init); |
| 822 | |
| 823 | static __exit void ccid2_module_exit(void) |
| 824 | { |
| 825 | ccid_unregister(&ccid2); |
| 826 | } |
| 827 | module_exit(ccid2_module_exit); |
| 828 | |
| 829 | MODULE_AUTHOR("Andrea Bittau <a.bittau@cs.ucl.ac.uk>"); |
Arnaldo Carvalho de Melo | c0c736d | 2006-03-20 22:05:37 -0800 | [diff] [blame] | 830 | MODULE_DESCRIPTION("DCCP TCP-Like (CCID2) CCID"); |
Andrea Bittau | 2a91aa3 | 2006-03-20 17:41:47 -0800 | [diff] [blame] | 831 | MODULE_LICENSE("GPL"); |
| 832 | MODULE_ALIAS("net-dccp-ccid-2"); |