Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * net/sched/sch_netem.c Network emulator |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version |
Stephen Hemminger | 798b6b1 | 2006-10-22 20:16:57 -0700 | [diff] [blame] | 7 | * 2 of the License. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 8 | * |
| 9 | * Many of the algorithms and ideas for this came from |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 10 | * NIST Net which is not copyrighted. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * |
| 12 | * Authors: Stephen Hemminger <shemminger@osdl.org> |
| 13 | * Catalin(ux aka Dino) BOIE <catab at umbrella dot ro> |
| 14 | */ |
| 15 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 16 | #include <linux/module.h> |
| 17 | #include <linux/bitops.h> |
| 18 | #include <linux/types.h> |
| 19 | #include <linux/kernel.h> |
| 20 | #include <linux/errno.h> |
| 21 | #include <linux/netdevice.h> |
| 22 | #include <linux/skbuff.h> |
| 23 | #include <linux/rtnetlink.h> |
| 24 | |
| 25 | #include <net/pkt_sched.h> |
| 26 | |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 27 | #define VERSION "1.2" |
Stephen Hemminger | eb229c4 | 2005-11-03 13:49:01 -0800 | [diff] [blame] | 28 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 29 | /* Network Emulation Queuing algorithm. |
| 30 | ==================================== |
| 31 | |
| 32 | Sources: [1] Mark Carson, Darrin Santay, "NIST Net - A Linux-based |
| 33 | Network Emulation Tool |
| 34 | [2] Luigi Rizzo, DummyNet for FreeBSD |
| 35 | |
| 36 | ---------------------------------------------------------------- |
| 37 | |
| 38 | This started out as a simple way to delay outgoing packets to |
| 39 | test TCP but has grown to include most of the functionality |
| 40 | of a full blown network emulator like NISTnet. It can delay |
| 41 | packets and add random jitter (and correlation). The random |
| 42 | distribution can be loaded from a table as well to provide |
| 43 | normal, Pareto, or experimental curves. Packet loss, |
| 44 | duplication, and reordering can also be emulated. |
| 45 | |
| 46 | This qdisc does not do classification that can be handled in |
| 47 | layering other disciplines. It does not need to do bandwidth |
| 48 | control either since that can be handled by using token |
| 49 | bucket or other rate control. |
| 50 | |
| 51 | The simulator is limited by the Linux timer resolution |
| 52 | and will create packet bursts on the HZ boundary (1ms). |
| 53 | */ |
| 54 | |
| 55 | struct netem_sched_data { |
| 56 | struct Qdisc *qdisc; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | struct timer_list timer; |
| 58 | |
| 59 | u32 latency; |
| 60 | u32 loss; |
| 61 | u32 limit; |
| 62 | u32 counter; |
| 63 | u32 gap; |
| 64 | u32 jitter; |
| 65 | u32 duplicate; |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 66 | u32 reorder; |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 67 | u32 corrupt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 68 | |
| 69 | struct crndstate { |
| 70 | unsigned long last; |
| 71 | unsigned long rho; |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 72 | } delay_cor, loss_cor, dup_cor, reorder_cor, corrupt_cor; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 73 | |
| 74 | struct disttable { |
| 75 | u32 size; |
| 76 | s16 table[0]; |
| 77 | } *delay_dist; |
| 78 | }; |
| 79 | |
| 80 | /* Time stamp put into socket buffer control block */ |
| 81 | struct netem_skb_cb { |
| 82 | psched_time_t time_to_send; |
| 83 | }; |
| 84 | |
| 85 | /* init_crandom - initialize correlated random number generator |
| 86 | * Use entropy source for initial seed. |
| 87 | */ |
| 88 | static void init_crandom(struct crndstate *state, unsigned long rho) |
| 89 | { |
| 90 | state->rho = rho; |
| 91 | state->last = net_random(); |
| 92 | } |
| 93 | |
| 94 | /* get_crandom - correlated random number generator |
| 95 | * Next number depends on last value. |
| 96 | * rho is scaled to avoid floating point. |
| 97 | */ |
| 98 | static unsigned long get_crandom(struct crndstate *state) |
| 99 | { |
| 100 | u64 value, rho; |
| 101 | unsigned long answer; |
| 102 | |
| 103 | if (state->rho == 0) /* no correllation */ |
| 104 | return net_random(); |
| 105 | |
| 106 | value = net_random(); |
| 107 | rho = (u64)state->rho + 1; |
| 108 | answer = (value * ((1ull<<32) - rho) + state->last * rho) >> 32; |
| 109 | state->last = answer; |
| 110 | return answer; |
| 111 | } |
| 112 | |
| 113 | /* tabledist - return a pseudo-randomly distributed value with mean mu and |
| 114 | * std deviation sigma. Uses table lookup to approximate the desired |
| 115 | * distribution, and a uniformly-distributed pseudo-random source. |
| 116 | */ |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 117 | static long tabledist(unsigned long mu, long sigma, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 118 | struct crndstate *state, const struct disttable *dist) |
| 119 | { |
| 120 | long t, x; |
| 121 | unsigned long rnd; |
| 122 | |
| 123 | if (sigma == 0) |
| 124 | return mu; |
| 125 | |
| 126 | rnd = get_crandom(state); |
| 127 | |
| 128 | /* default uniform distribution */ |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 129 | if (dist == NULL) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 130 | return (rnd % (2*sigma)) - sigma + mu; |
| 131 | |
| 132 | t = dist->table[rnd % dist->size]; |
| 133 | x = (sigma % NETEM_DIST_SCALE) * t; |
| 134 | if (x >= 0) |
| 135 | x += NETEM_DIST_SCALE/2; |
| 136 | else |
| 137 | x -= NETEM_DIST_SCALE/2; |
| 138 | |
| 139 | return x / NETEM_DIST_SCALE + (sigma / NETEM_DIST_SCALE) * t + mu; |
| 140 | } |
| 141 | |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 142 | /* |
| 143 | * Insert one skb into qdisc. |
| 144 | * Note: parent depends on return value to account for queue length. |
| 145 | * NET_XMIT_DROP: queue length didn't change. |
| 146 | * NET_XMIT_SUCCESS: one skb was queued. |
| 147 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 148 | static int netem_enqueue(struct sk_buff *skb, struct Qdisc *sch) |
| 149 | { |
| 150 | struct netem_sched_data *q = qdisc_priv(sch); |
Guillaume Chazarain | 89e1df7 | 2006-07-21 14:45:25 -0700 | [diff] [blame] | 151 | /* We don't fill cb now as skb_unshare() may invalidate it */ |
| 152 | struct netem_skb_cb *cb; |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 153 | struct sk_buff *skb2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | int ret; |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 155 | int count = 1; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 156 | |
Stephen Hemminger | 771018e | 2005-05-03 16:24:32 -0700 | [diff] [blame] | 157 | pr_debug("netem_enqueue skb=%p\n", skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 159 | /* Random duplication */ |
| 160 | if (q->duplicate && q->duplicate >= get_crandom(&q->dup_cor)) |
| 161 | ++count; |
| 162 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 163 | /* Random packet drop 0 => none, ~0 => all */ |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 164 | if (q->loss && q->loss >= get_crandom(&q->loss_cor)) |
| 165 | --count; |
| 166 | |
| 167 | if (count == 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 168 | sch->qstats.drops++; |
| 169 | kfree_skb(skb); |
Stephen Hemminger | 89bbb0a3 | 2006-04-28 12:11:36 -0700 | [diff] [blame] | 170 | return NET_XMIT_BYPASS; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 171 | } |
| 172 | |
David S. Miller | 4e8a520 | 2006-10-22 21:00:33 -0700 | [diff] [blame] | 173 | skb_orphan(skb); |
| 174 | |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 175 | /* |
| 176 | * If we need to duplicate packet, then re-insert at top of the |
| 177 | * qdisc tree, since parent queuer expects that only one |
| 178 | * skb will be queued. |
| 179 | */ |
| 180 | if (count > 1 && (skb2 = skb_clone(skb, GFP_ATOMIC)) != NULL) { |
| 181 | struct Qdisc *rootq = sch->dev->qdisc; |
| 182 | u32 dupsave = q->duplicate; /* prevent duplicating a dup... */ |
| 183 | q->duplicate = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | |
Stephen Hemminger | 0afb51e | 2005-05-26 12:53:49 -0700 | [diff] [blame] | 185 | rootq->enqueue(skb2, rootq); |
| 186 | q->duplicate = dupsave; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 187 | } |
| 188 | |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 189 | /* |
| 190 | * Randomized packet corruption. |
| 191 | * Make copy if needed since we are modifying |
| 192 | * If packet is going to be hardware checksummed, then |
| 193 | * do it now in software before we mangle it. |
| 194 | */ |
| 195 | if (q->corrupt && q->corrupt >= get_crandom(&q->corrupt_cor)) { |
| 196 | if (!(skb = skb_unshare(skb, GFP_ATOMIC)) |
Patrick McHardy | 84fa793 | 2006-08-29 16:44:56 -0700 | [diff] [blame] | 197 | || (skb->ip_summed == CHECKSUM_PARTIAL |
| 198 | && skb_checksum_help(skb))) { |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 199 | sch->qstats.drops++; |
| 200 | return NET_XMIT_DROP; |
| 201 | } |
| 202 | |
| 203 | skb->data[net_random() % skb_headlen(skb)] ^= 1<<(net_random() % 8); |
| 204 | } |
| 205 | |
Guillaume Chazarain | 89e1df7 | 2006-07-21 14:45:25 -0700 | [diff] [blame] | 206 | cb = (struct netem_skb_cb *)skb->cb; |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 207 | if (q->gap == 0 /* not doing reordering */ |
| 208 | || q->counter < q->gap /* inside last reordering gap */ |
| 209 | || q->reorder < get_crandom(&q->reorder_cor)) { |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 210 | psched_time_t now; |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 211 | psched_tdiff_t delay; |
| 212 | |
| 213 | delay = tabledist(q->latency, q->jitter, |
| 214 | &q->delay_cor, q->delay_dist); |
| 215 | |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 216 | PSCHED_GET_TIME(now); |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 217 | PSCHED_TADD2(now, delay, cb->time_to_send); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 218 | ++q->counter; |
| 219 | ret = q->qdisc->enqueue(skb, q->qdisc); |
| 220 | } else { |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 221 | /* |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 222 | * Do re-ordering by putting one out of N packets at the front |
| 223 | * of the queue. |
| 224 | */ |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 225 | PSCHED_GET_TIME(cb->time_to_send); |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 226 | q->counter = 0; |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 227 | ret = q->qdisc->ops->requeue(skb, q->qdisc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 228 | } |
| 229 | |
| 230 | if (likely(ret == NET_XMIT_SUCCESS)) { |
| 231 | sch->q.qlen++; |
| 232 | sch->bstats.bytes += skb->len; |
| 233 | sch->bstats.packets++; |
| 234 | } else |
| 235 | sch->qstats.drops++; |
| 236 | |
Stephen Hemminger | d5d75cd | 2005-05-03 16:24:57 -0700 | [diff] [blame] | 237 | pr_debug("netem: enqueue ret %d\n", ret); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 238 | return ret; |
| 239 | } |
| 240 | |
| 241 | /* Requeue packets but don't change time stamp */ |
| 242 | static int netem_requeue(struct sk_buff *skb, struct Qdisc *sch) |
| 243 | { |
| 244 | struct netem_sched_data *q = qdisc_priv(sch); |
| 245 | int ret; |
| 246 | |
| 247 | if ((ret = q->qdisc->ops->requeue(skb, q->qdisc)) == 0) { |
| 248 | sch->q.qlen++; |
| 249 | sch->qstats.requeues++; |
| 250 | } |
| 251 | |
| 252 | return ret; |
| 253 | } |
| 254 | |
| 255 | static unsigned int netem_drop(struct Qdisc* sch) |
| 256 | { |
| 257 | struct netem_sched_data *q = qdisc_priv(sch); |
Patrick McHardy | 6d037a2 | 2006-03-20 19:00:49 -0800 | [diff] [blame] | 258 | unsigned int len = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | |
Patrick McHardy | 6d037a2 | 2006-03-20 19:00:49 -0800 | [diff] [blame] | 260 | if (q->qdisc->ops->drop && (len = q->qdisc->ops->drop(q->qdisc)) != 0) { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | sch->q.qlen--; |
| 262 | sch->qstats.drops++; |
| 263 | } |
| 264 | return len; |
| 265 | } |
| 266 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 267 | static struct sk_buff *netem_dequeue(struct Qdisc *sch) |
| 268 | { |
| 269 | struct netem_sched_data *q = qdisc_priv(sch); |
| 270 | struct sk_buff *skb; |
| 271 | |
| 272 | skb = q->qdisc->dequeue(q->qdisc); |
Stephen Hemminger | 771018e | 2005-05-03 16:24:32 -0700 | [diff] [blame] | 273 | if (skb) { |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 274 | const struct netem_skb_cb *cb |
| 275 | = (const struct netem_skb_cb *)skb->cb; |
| 276 | psched_time_t now; |
Stephen Hemminger | 771018e | 2005-05-03 16:24:32 -0700 | [diff] [blame] | 277 | |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 278 | /* if more time remaining? */ |
| 279 | PSCHED_GET_TIME(now); |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 280 | |
| 281 | if (PSCHED_TLESS(cb->time_to_send, now)) { |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 282 | pr_debug("netem_dequeue: return skb=%p\n", skb); |
| 283 | sch->q.qlen--; |
| 284 | sch->flags &= ~TCQ_F_THROTTLED; |
| 285 | return skb; |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 286 | } else { |
| 287 | psched_tdiff_t delay = PSCHED_TDIFF(cb->time_to_send, now); |
| 288 | |
| 289 | if (q->qdisc->ops->requeue(skb, q->qdisc) != NET_XMIT_SUCCESS) { |
Patrick McHardy | e488eaf | 2006-11-29 17:37:42 -0800 | [diff] [blame] | 290 | qdisc_tree_decrease_qlen(q->qdisc, 1); |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 291 | sch->qstats.drops++; |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 292 | printk(KERN_ERR "netem: queue discpline %s could not requeue\n", |
| 293 | q->qdisc->ops->id); |
Stephen Hemminger | 07aaa11 | 2005-11-03 13:43:07 -0800 | [diff] [blame] | 294 | } |
| 295 | |
| 296 | mod_timer(&q->timer, jiffies + PSCHED_US2JIFFIE(delay)); |
| 297 | sch->flags |= TCQ_F_THROTTLED; |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 298 | } |
Stephen Hemminger | 0f9f32a | 2005-05-26 12:55:01 -0700 | [diff] [blame] | 299 | } |
| 300 | |
| 301 | return NULL; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 302 | } |
| 303 | |
| 304 | static void netem_watchdog(unsigned long arg) |
| 305 | { |
| 306 | struct Qdisc *sch = (struct Qdisc *)arg; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 307 | |
Stephen Hemminger | 771018e | 2005-05-03 16:24:32 -0700 | [diff] [blame] | 308 | pr_debug("netem_watchdog qlen=%d\n", sch->q.qlen); |
| 309 | sch->flags &= ~TCQ_F_THROTTLED; |
| 310 | netif_schedule(sch->dev); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 311 | } |
| 312 | |
| 313 | static void netem_reset(struct Qdisc *sch) |
| 314 | { |
| 315 | struct netem_sched_data *q = qdisc_priv(sch); |
| 316 | |
| 317 | qdisc_reset(q->qdisc); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 318 | sch->q.qlen = 0; |
Stephen Hemminger | 771018e | 2005-05-03 16:24:32 -0700 | [diff] [blame] | 319 | sch->flags &= ~TCQ_F_THROTTLED; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 320 | del_timer_sync(&q->timer); |
| 321 | } |
| 322 | |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 323 | /* Pass size change message down to embedded FIFO */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 324 | static int set_fifo_limit(struct Qdisc *q, int limit) |
| 325 | { |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 326 | struct rtattr *rta; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 327 | int ret = -ENOMEM; |
| 328 | |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 329 | /* Hack to avoid sending change message to non-FIFO */ |
| 330 | if (strncmp(q->ops->id + 1, "fifo", 4) != 0) |
| 331 | return 0; |
| 332 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 333 | rta = kmalloc(RTA_LENGTH(sizeof(struct tc_fifo_qopt)), GFP_KERNEL); |
| 334 | if (rta) { |
| 335 | rta->rta_type = RTM_NEWQDISC; |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 336 | rta->rta_len = RTA_LENGTH(sizeof(struct tc_fifo_qopt)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 337 | ((struct tc_fifo_qopt *)RTA_DATA(rta))->limit = limit; |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 338 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 339 | ret = q->ops->change(q, rta); |
| 340 | kfree(rta); |
| 341 | } |
| 342 | return ret; |
| 343 | } |
| 344 | |
| 345 | /* |
| 346 | * Distribution data is a variable size payload containing |
| 347 | * signed 16 bit values. |
| 348 | */ |
| 349 | static int get_dist_table(struct Qdisc *sch, const struct rtattr *attr) |
| 350 | { |
| 351 | struct netem_sched_data *q = qdisc_priv(sch); |
| 352 | unsigned long n = RTA_PAYLOAD(attr)/sizeof(__s16); |
| 353 | const __s16 *data = RTA_DATA(attr); |
| 354 | struct disttable *d; |
| 355 | int i; |
| 356 | |
| 357 | if (n > 65536) |
| 358 | return -EINVAL; |
| 359 | |
| 360 | d = kmalloc(sizeof(*d) + n*sizeof(d->table[0]), GFP_KERNEL); |
| 361 | if (!d) |
| 362 | return -ENOMEM; |
| 363 | |
| 364 | d->size = n; |
| 365 | for (i = 0; i < n; i++) |
| 366 | d->table[i] = data[i]; |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 367 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 368 | spin_lock_bh(&sch->dev->queue_lock); |
| 369 | d = xchg(&q->delay_dist, d); |
| 370 | spin_unlock_bh(&sch->dev->queue_lock); |
| 371 | |
| 372 | kfree(d); |
| 373 | return 0; |
| 374 | } |
| 375 | |
| 376 | static int get_correlation(struct Qdisc *sch, const struct rtattr *attr) |
| 377 | { |
| 378 | struct netem_sched_data *q = qdisc_priv(sch); |
| 379 | const struct tc_netem_corr *c = RTA_DATA(attr); |
| 380 | |
| 381 | if (RTA_PAYLOAD(attr) != sizeof(*c)) |
| 382 | return -EINVAL; |
| 383 | |
| 384 | init_crandom(&q->delay_cor, c->delay_corr); |
| 385 | init_crandom(&q->loss_cor, c->loss_corr); |
| 386 | init_crandom(&q->dup_cor, c->dup_corr); |
| 387 | return 0; |
| 388 | } |
| 389 | |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 390 | static int get_reorder(struct Qdisc *sch, const struct rtattr *attr) |
| 391 | { |
| 392 | struct netem_sched_data *q = qdisc_priv(sch); |
| 393 | const struct tc_netem_reorder *r = RTA_DATA(attr); |
| 394 | |
| 395 | if (RTA_PAYLOAD(attr) != sizeof(*r)) |
| 396 | return -EINVAL; |
| 397 | |
| 398 | q->reorder = r->probability; |
| 399 | init_crandom(&q->reorder_cor, r->correlation); |
| 400 | return 0; |
| 401 | } |
| 402 | |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 403 | static int get_corrupt(struct Qdisc *sch, const struct rtattr *attr) |
| 404 | { |
| 405 | struct netem_sched_data *q = qdisc_priv(sch); |
| 406 | const struct tc_netem_corrupt *r = RTA_DATA(attr); |
| 407 | |
| 408 | if (RTA_PAYLOAD(attr) != sizeof(*r)) |
| 409 | return -EINVAL; |
| 410 | |
| 411 | q->corrupt = r->probability; |
| 412 | init_crandom(&q->corrupt_cor, r->correlation); |
| 413 | return 0; |
| 414 | } |
| 415 | |
| 416 | /* Parse netlink message to set options */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 417 | static int netem_change(struct Qdisc *sch, struct rtattr *opt) |
| 418 | { |
| 419 | struct netem_sched_data *q = qdisc_priv(sch); |
| 420 | struct tc_netem_qopt *qopt; |
| 421 | int ret; |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 422 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 423 | if (opt == NULL || RTA_PAYLOAD(opt) < sizeof(*qopt)) |
| 424 | return -EINVAL; |
| 425 | |
| 426 | qopt = RTA_DATA(opt); |
| 427 | ret = set_fifo_limit(q->qdisc, qopt->limit); |
| 428 | if (ret) { |
| 429 | pr_debug("netem: can't set fifo limit\n"); |
| 430 | return ret; |
| 431 | } |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 432 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 433 | q->latency = qopt->latency; |
| 434 | q->jitter = qopt->jitter; |
| 435 | q->limit = qopt->limit; |
| 436 | q->gap = qopt->gap; |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 437 | q->counter = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 438 | q->loss = qopt->loss; |
| 439 | q->duplicate = qopt->duplicate; |
| 440 | |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 441 | /* for compatiablity with earlier versions. |
| 442 | * if gap is set, need to assume 100% probablity |
| 443 | */ |
| 444 | q->reorder = ~0; |
| 445 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 446 | /* Handle nested options after initial queue options. |
| 447 | * Should have put all options in nested format but too late now. |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 448 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 449 | if (RTA_PAYLOAD(opt) > sizeof(*qopt)) { |
| 450 | struct rtattr *tb[TCA_NETEM_MAX]; |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 451 | if (rtattr_parse(tb, TCA_NETEM_MAX, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 452 | RTA_DATA(opt) + sizeof(*qopt), |
| 453 | RTA_PAYLOAD(opt) - sizeof(*qopt))) |
| 454 | return -EINVAL; |
| 455 | |
| 456 | if (tb[TCA_NETEM_CORR-1]) { |
| 457 | ret = get_correlation(sch, tb[TCA_NETEM_CORR-1]); |
| 458 | if (ret) |
| 459 | return ret; |
| 460 | } |
| 461 | |
| 462 | if (tb[TCA_NETEM_DELAY_DIST-1]) { |
| 463 | ret = get_dist_table(sch, tb[TCA_NETEM_DELAY_DIST-1]); |
| 464 | if (ret) |
| 465 | return ret; |
| 466 | } |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 467 | |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 468 | if (tb[TCA_NETEM_REORDER-1]) { |
| 469 | ret = get_reorder(sch, tb[TCA_NETEM_REORDER-1]); |
| 470 | if (ret) |
| 471 | return ret; |
| 472 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 473 | |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 474 | if (tb[TCA_NETEM_CORRUPT-1]) { |
| 475 | ret = get_corrupt(sch, tb[TCA_NETEM_CORRUPT-1]); |
| 476 | if (ret) |
| 477 | return ret; |
| 478 | } |
| 479 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 480 | |
| 481 | return 0; |
| 482 | } |
| 483 | |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 484 | /* |
| 485 | * Special case version of FIFO queue for use by netem. |
| 486 | * It queues in order based on timestamps in skb's |
| 487 | */ |
| 488 | struct fifo_sched_data { |
| 489 | u32 limit; |
| 490 | }; |
| 491 | |
| 492 | static int tfifo_enqueue(struct sk_buff *nskb, struct Qdisc *sch) |
| 493 | { |
| 494 | struct fifo_sched_data *q = qdisc_priv(sch); |
| 495 | struct sk_buff_head *list = &sch->q; |
| 496 | const struct netem_skb_cb *ncb |
| 497 | = (const struct netem_skb_cb *)nskb->cb; |
| 498 | struct sk_buff *skb; |
| 499 | |
| 500 | if (likely(skb_queue_len(list) < q->limit)) { |
| 501 | skb_queue_reverse_walk(list, skb) { |
| 502 | const struct netem_skb_cb *cb |
| 503 | = (const struct netem_skb_cb *)skb->cb; |
| 504 | |
Andrea Bittau | aa87516 | 2005-11-20 13:41:05 -0800 | [diff] [blame] | 505 | if (!PSCHED_TLESS(ncb->time_to_send, cb->time_to_send)) |
Stephen Hemminger | 300ce17 | 2005-10-30 13:47:34 -0800 | [diff] [blame] | 506 | break; |
| 507 | } |
| 508 | |
| 509 | __skb_queue_after(list, skb, nskb); |
| 510 | |
| 511 | sch->qstats.backlog += nskb->len; |
| 512 | sch->bstats.bytes += nskb->len; |
| 513 | sch->bstats.packets++; |
| 514 | |
| 515 | return NET_XMIT_SUCCESS; |
| 516 | } |
| 517 | |
| 518 | return qdisc_drop(nskb, sch); |
| 519 | } |
| 520 | |
| 521 | static int tfifo_init(struct Qdisc *sch, struct rtattr *opt) |
| 522 | { |
| 523 | struct fifo_sched_data *q = qdisc_priv(sch); |
| 524 | |
| 525 | if (opt) { |
| 526 | struct tc_fifo_qopt *ctl = RTA_DATA(opt); |
| 527 | if (RTA_PAYLOAD(opt) < sizeof(*ctl)) |
| 528 | return -EINVAL; |
| 529 | |
| 530 | q->limit = ctl->limit; |
| 531 | } else |
| 532 | q->limit = max_t(u32, sch->dev->tx_queue_len, 1); |
| 533 | |
| 534 | return 0; |
| 535 | } |
| 536 | |
| 537 | static int tfifo_dump(struct Qdisc *sch, struct sk_buff *skb) |
| 538 | { |
| 539 | struct fifo_sched_data *q = qdisc_priv(sch); |
| 540 | struct tc_fifo_qopt opt = { .limit = q->limit }; |
| 541 | |
| 542 | RTA_PUT(skb, TCA_OPTIONS, sizeof(opt), &opt); |
| 543 | return skb->len; |
| 544 | |
| 545 | rtattr_failure: |
| 546 | return -1; |
| 547 | } |
| 548 | |
| 549 | static struct Qdisc_ops tfifo_qdisc_ops = { |
| 550 | .id = "tfifo", |
| 551 | .priv_size = sizeof(struct fifo_sched_data), |
| 552 | .enqueue = tfifo_enqueue, |
| 553 | .dequeue = qdisc_dequeue_head, |
| 554 | .requeue = qdisc_requeue, |
| 555 | .drop = qdisc_queue_drop, |
| 556 | .init = tfifo_init, |
| 557 | .reset = qdisc_reset_queue, |
| 558 | .change = tfifo_init, |
| 559 | .dump = tfifo_dump, |
| 560 | }; |
| 561 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 562 | static int netem_init(struct Qdisc *sch, struct rtattr *opt) |
| 563 | { |
| 564 | struct netem_sched_data *q = qdisc_priv(sch); |
| 565 | int ret; |
| 566 | |
| 567 | if (!opt) |
| 568 | return -EINVAL; |
| 569 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 570 | init_timer(&q->timer); |
| 571 | q->timer.function = netem_watchdog; |
| 572 | q->timer.data = (unsigned long) sch; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 573 | |
Patrick McHardy | 9f9afec | 2006-11-29 17:35:18 -0800 | [diff] [blame] | 574 | q->qdisc = qdisc_create_dflt(sch->dev, &tfifo_qdisc_ops, |
| 575 | TC_H_MAKE(sch->handle, 1)); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 576 | if (!q->qdisc) { |
| 577 | pr_debug("netem: qdisc create failed\n"); |
| 578 | return -ENOMEM; |
| 579 | } |
| 580 | |
| 581 | ret = netem_change(sch, opt); |
| 582 | if (ret) { |
| 583 | pr_debug("netem: change failed\n"); |
| 584 | qdisc_destroy(q->qdisc); |
| 585 | } |
| 586 | return ret; |
| 587 | } |
| 588 | |
| 589 | static void netem_destroy(struct Qdisc *sch) |
| 590 | { |
| 591 | struct netem_sched_data *q = qdisc_priv(sch); |
| 592 | |
| 593 | del_timer_sync(&q->timer); |
| 594 | qdisc_destroy(q->qdisc); |
| 595 | kfree(q->delay_dist); |
| 596 | } |
| 597 | |
| 598 | static int netem_dump(struct Qdisc *sch, struct sk_buff *skb) |
| 599 | { |
| 600 | const struct netem_sched_data *q = qdisc_priv(sch); |
| 601 | unsigned char *b = skb->tail; |
| 602 | struct rtattr *rta = (struct rtattr *) b; |
| 603 | struct tc_netem_qopt qopt; |
| 604 | struct tc_netem_corr cor; |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 605 | struct tc_netem_reorder reorder; |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 606 | struct tc_netem_corrupt corrupt; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | |
| 608 | qopt.latency = q->latency; |
| 609 | qopt.jitter = q->jitter; |
| 610 | qopt.limit = q->limit; |
| 611 | qopt.loss = q->loss; |
| 612 | qopt.gap = q->gap; |
| 613 | qopt.duplicate = q->duplicate; |
| 614 | RTA_PUT(skb, TCA_OPTIONS, sizeof(qopt), &qopt); |
| 615 | |
| 616 | cor.delay_corr = q->delay_cor.rho; |
| 617 | cor.loss_corr = q->loss_cor.rho; |
| 618 | cor.dup_corr = q->dup_cor.rho; |
| 619 | RTA_PUT(skb, TCA_NETEM_CORR, sizeof(cor), &cor); |
Stephen Hemminger | 0dca51d | 2005-05-26 12:55:48 -0700 | [diff] [blame] | 620 | |
| 621 | reorder.probability = q->reorder; |
| 622 | reorder.correlation = q->reorder_cor.rho; |
| 623 | RTA_PUT(skb, TCA_NETEM_REORDER, sizeof(reorder), &reorder); |
| 624 | |
Stephen Hemminger | c865e5d | 2005-12-21 19:03:44 -0800 | [diff] [blame] | 625 | corrupt.probability = q->corrupt; |
| 626 | corrupt.correlation = q->corrupt_cor.rho; |
| 627 | RTA_PUT(skb, TCA_NETEM_CORRUPT, sizeof(corrupt), &corrupt); |
| 628 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | rta->rta_len = skb->tail - b; |
| 630 | |
| 631 | return skb->len; |
| 632 | |
| 633 | rtattr_failure: |
| 634 | skb_trim(skb, b - skb->data); |
| 635 | return -1; |
| 636 | } |
| 637 | |
| 638 | static int netem_dump_class(struct Qdisc *sch, unsigned long cl, |
| 639 | struct sk_buff *skb, struct tcmsg *tcm) |
| 640 | { |
| 641 | struct netem_sched_data *q = qdisc_priv(sch); |
| 642 | |
| 643 | if (cl != 1) /* only one class */ |
| 644 | return -ENOENT; |
| 645 | |
| 646 | tcm->tcm_handle |= TC_H_MIN(1); |
| 647 | tcm->tcm_info = q->qdisc->handle; |
| 648 | |
| 649 | return 0; |
| 650 | } |
| 651 | |
| 652 | static int netem_graft(struct Qdisc *sch, unsigned long arg, struct Qdisc *new, |
| 653 | struct Qdisc **old) |
| 654 | { |
| 655 | struct netem_sched_data *q = qdisc_priv(sch); |
| 656 | |
| 657 | if (new == NULL) |
| 658 | new = &noop_qdisc; |
| 659 | |
| 660 | sch_tree_lock(sch); |
| 661 | *old = xchg(&q->qdisc, new); |
Patrick McHardy | 5e50da0 | 2006-11-29 17:36:20 -0800 | [diff] [blame] | 662 | qdisc_tree_decrease_qlen(*old, (*old)->q.qlen); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 663 | qdisc_reset(*old); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 664 | sch_tree_unlock(sch); |
| 665 | |
| 666 | return 0; |
| 667 | } |
| 668 | |
| 669 | static struct Qdisc *netem_leaf(struct Qdisc *sch, unsigned long arg) |
| 670 | { |
| 671 | struct netem_sched_data *q = qdisc_priv(sch); |
| 672 | return q->qdisc; |
| 673 | } |
| 674 | |
| 675 | static unsigned long netem_get(struct Qdisc *sch, u32 classid) |
| 676 | { |
| 677 | return 1; |
| 678 | } |
| 679 | |
| 680 | static void netem_put(struct Qdisc *sch, unsigned long arg) |
| 681 | { |
| 682 | } |
| 683 | |
YOSHIFUJI Hideaki | 10297b9 | 2007-02-09 23:25:16 +0900 | [diff] [blame] | 684 | static int netem_change_class(struct Qdisc *sch, u32 classid, u32 parentid, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 685 | struct rtattr **tca, unsigned long *arg) |
| 686 | { |
| 687 | return -ENOSYS; |
| 688 | } |
| 689 | |
| 690 | static int netem_delete(struct Qdisc *sch, unsigned long arg) |
| 691 | { |
| 692 | return -ENOSYS; |
| 693 | } |
| 694 | |
| 695 | static void netem_walk(struct Qdisc *sch, struct qdisc_walker *walker) |
| 696 | { |
| 697 | if (!walker->stop) { |
| 698 | if (walker->count >= walker->skip) |
| 699 | if (walker->fn(sch, 1, walker) < 0) { |
| 700 | walker->stop = 1; |
| 701 | return; |
| 702 | } |
| 703 | walker->count++; |
| 704 | } |
| 705 | } |
| 706 | |
| 707 | static struct tcf_proto **netem_find_tcf(struct Qdisc *sch, unsigned long cl) |
| 708 | { |
| 709 | return NULL; |
| 710 | } |
| 711 | |
| 712 | static struct Qdisc_class_ops netem_class_ops = { |
| 713 | .graft = netem_graft, |
| 714 | .leaf = netem_leaf, |
| 715 | .get = netem_get, |
| 716 | .put = netem_put, |
| 717 | .change = netem_change_class, |
| 718 | .delete = netem_delete, |
| 719 | .walk = netem_walk, |
| 720 | .tcf_chain = netem_find_tcf, |
| 721 | .dump = netem_dump_class, |
| 722 | }; |
| 723 | |
| 724 | static struct Qdisc_ops netem_qdisc_ops = { |
| 725 | .id = "netem", |
| 726 | .cl_ops = &netem_class_ops, |
| 727 | .priv_size = sizeof(struct netem_sched_data), |
| 728 | .enqueue = netem_enqueue, |
| 729 | .dequeue = netem_dequeue, |
| 730 | .requeue = netem_requeue, |
| 731 | .drop = netem_drop, |
| 732 | .init = netem_init, |
| 733 | .reset = netem_reset, |
| 734 | .destroy = netem_destroy, |
| 735 | .change = netem_change, |
| 736 | .dump = netem_dump, |
| 737 | .owner = THIS_MODULE, |
| 738 | }; |
| 739 | |
| 740 | |
| 741 | static int __init netem_module_init(void) |
| 742 | { |
Stephen Hemminger | eb229c4 | 2005-11-03 13:49:01 -0800 | [diff] [blame] | 743 | pr_info("netem: version " VERSION "\n"); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 744 | return register_qdisc(&netem_qdisc_ops); |
| 745 | } |
| 746 | static void __exit netem_module_exit(void) |
| 747 | { |
| 748 | unregister_qdisc(&netem_qdisc_ops); |
| 749 | } |
| 750 | module_init(netem_module_init) |
| 751 | module_exit(netem_module_exit) |
| 752 | MODULE_LICENSE("GPL"); |