1 /*- 2 * Copyright (c) 2002-2008 Sam Leffler, Errno Consulting 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 * 25 * $FreeBSD: head/sys/net80211/ieee80211_power.c 186302 2008-12-18 23:00:09Z sam $ 26 * $DragonFly$ 27 */ 28 29 /* 30 * IEEE 802.11 power save support. 31 */ 32 #include "opt_wlan.h" 33 34 #include <sys/param.h> 35 #include <sys/systm.h> 36 #include <sys/kernel.h> 37 38 #include <sys/socket.h> 39 40 #include <net/if.h> 41 #include <net/if_media.h> 42 #include <net/ethernet.h> 43 #include <net/route.h> 44 45 #include <netproto/802_11/ieee80211_var.h> 46 47 #include <net/bpf.h> 48 49 static void ieee80211_update_ps(struct ieee80211vap *, int); 50 static int ieee80211_set_tim(struct ieee80211_node *, int); 51 52 MALLOC_DEFINE(M_80211_POWER, "80211power", "802.11 power save state"); 53 54 void 55 ieee80211_power_attach(struct ieee80211com *ic) 56 { 57 } 58 59 void 60 ieee80211_power_detach(struct ieee80211com *ic) 61 { 62 } 63 64 void 65 ieee80211_power_vattach(struct ieee80211vap *vap) 66 { 67 if (vap->iv_opmode == IEEE80211_M_HOSTAP || 68 vap->iv_opmode == IEEE80211_M_IBSS) { 69 /* NB: driver should override */ 70 vap->iv_update_ps = ieee80211_update_ps; 71 vap->iv_set_tim = ieee80211_set_tim; 72 } 73 } 74 75 void 76 ieee80211_power_latevattach(struct ieee80211vap *vap) 77 { 78 /* 79 * Allocate these only if needed. Beware that we 80 * know adhoc mode doesn't support ATIM yet... 81 */ 82 if (vap->iv_opmode == IEEE80211_M_HOSTAP) { 83 vap->iv_tim_len = howmany(vap->iv_max_aid,8) * sizeof(uint8_t); 84 vap->iv_tim_bitmap = (uint8_t *) kmalloc(vap->iv_tim_len, 85 M_80211_POWER, M_INTWAIT | M_ZERO); 86 if (vap->iv_tim_bitmap == NULL) { 87 kprintf("%s: no memory for TIM bitmap!\n", __func__); 88 /* XXX good enough to keep from crashing? */ 89 vap->iv_tim_len = 0; 90 } 91 } 92 } 93 94 void 95 ieee80211_power_vdetach(struct ieee80211vap *vap) 96 { 97 if (vap->iv_tim_bitmap != NULL) { 98 kfree(vap->iv_tim_bitmap, M_80211_POWER); 99 vap->iv_tim_bitmap = NULL; 100 } 101 } 102 103 void 104 ieee80211_psq_init(struct ieee80211_psq *psq, const char *name) 105 { 106 memset(psq, 0, sizeof(psq)); 107 psq->psq_maxlen = IEEE80211_PS_MAX_QUEUE; 108 IEEE80211_PSQ_INIT(psq, name); /* OS-dependent setup */ 109 } 110 111 void 112 ieee80211_psq_cleanup(struct ieee80211_psq *psq) 113 { 114 #if 0 115 psq_drain(psq); /* XXX should not be needed? */ 116 #else 117 KASSERT(psq->psq_len == 0, ("%d frames on ps q", psq->psq_len)); 118 #endif 119 IEEE80211_PSQ_DESTROY(psq); /* OS-dependent cleanup */ 120 } 121 122 /* 123 * Return the highest priority frame in the ps queue. 124 */ 125 struct mbuf * 126 ieee80211_node_psq_dequeue(struct ieee80211_node *ni, int *qlen) 127 { 128 struct ieee80211_psq *psq = &ni->ni_psq; 129 struct ieee80211_psq_head *qhead; 130 struct mbuf *m; 131 132 IEEE80211_PSQ_LOCK(psq); 133 qhead = &psq->psq_head[0]; 134 again: 135 if ((m = qhead->head) != NULL) { 136 if ((qhead->head = m->m_nextpkt) == NULL) 137 qhead->tail = NULL; 138 KASSERT(qhead->len > 0, ("qhead len %d", qhead->len)); 139 qhead->len--; 140 KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len)); 141 psq->psq_len--; 142 m->m_nextpkt = NULL; 143 } 144 if (m == NULL && qhead == &psq->psq_head[0]) { 145 /* Algol-68 style for loop */ 146 qhead = &psq->psq_head[1]; 147 goto again; 148 } 149 if (qlen != NULL) 150 *qlen = psq->psq_len; 151 IEEE80211_PSQ_UNLOCK(psq); 152 return m; 153 } 154 155 /* 156 * Reclaim an mbuf from the ps q. If marked with M_ENCAP 157 * we assume there is a node reference that must be relcaimed. 158 */ 159 static void 160 psq_mfree(struct mbuf *m) 161 { 162 if (m->m_flags & M_ENCAP) { 163 struct ieee80211_node *ni = (void *) m->m_pkthdr.rcvif; 164 ieee80211_free_node(ni); 165 } 166 m->m_nextpkt = NULL; 167 m_freem(m); 168 } 169 170 /* 171 * Clear any frames queued in the power save queue. 172 * The number of frames that were present is returned. 173 */ 174 static int 175 psq_drain(struct ieee80211_psq *psq) 176 { 177 struct ieee80211_psq_head *qhead; 178 struct mbuf *m; 179 int qlen; 180 181 IEEE80211_PSQ_LOCK(psq); 182 qlen = psq->psq_len; 183 qhead = &psq->psq_head[0]; 184 again: 185 while ((m = qhead->head) != NULL) { 186 qhead->head = m->m_nextpkt; 187 psq_mfree(m); 188 } 189 qhead->tail = NULL; 190 qhead->len = 0; 191 if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */ 192 qhead = &psq->psq_head[1]; 193 goto again; 194 } 195 psq->psq_len = 0; 196 IEEE80211_PSQ_UNLOCK(psq); 197 198 return qlen; 199 } 200 201 /* 202 * Clear any frames queued in the power save queue. 203 * The number of frames that were present is returned. 204 */ 205 int 206 ieee80211_node_psq_drain(struct ieee80211_node *ni) 207 { 208 return psq_drain(&ni->ni_psq); 209 } 210 211 /* 212 * Age frames on the power save queue. The aging interval is 213 * 4 times the listen interval specified by the station. This 214 * number is factored into the age calculations when the frame 215 * is placed on the queue. We store ages as time differences 216 * so we can check and/or adjust only the head of the list. 217 * If a frame's age exceeds the threshold then discard it. 218 * The number of frames discarded is returned so the caller 219 * can check if it needs to adjust the tim. 220 */ 221 int 222 ieee80211_node_psq_age(struct ieee80211_node *ni) 223 { 224 struct ieee80211_psq *psq = &ni->ni_psq; 225 int discard = 0; 226 227 if (psq->psq_len != 0) { 228 #ifdef IEEE80211_DEBUG 229 struct ieee80211vap *vap = ni->ni_vap; 230 #endif 231 struct ieee80211_psq_head *qhead; 232 struct mbuf *m; 233 234 IEEE80211_PSQ_LOCK(psq); 235 qhead = &psq->psq_head[0]; 236 again: 237 while ((m = qhead->head) != NULL && 238 M_AGE_GET(m) < IEEE80211_INACT_WAIT) { 239 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 240 "discard frame, age %u", M_AGE_GET(m)); 241 if ((qhead->head = m->m_nextpkt) == NULL) 242 qhead->tail = NULL; 243 KASSERT(qhead->len > 0, ("qhead len %d", qhead->len)); 244 qhead->len--; 245 KASSERT(psq->psq_len > 0, ("psq len %d", psq->psq_len)); 246 psq->psq_len--; 247 psq_mfree(m); 248 discard++; 249 } 250 if (qhead == &psq->psq_head[0]) { /* Algol-68 style for loop */ 251 qhead = &psq->psq_head[1]; 252 goto again; 253 } 254 if (m != NULL) 255 M_AGE_SUB(m, IEEE80211_INACT_WAIT); 256 IEEE80211_PSQ_UNLOCK(psq); 257 258 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 259 "discard %u frames for age", discard); 260 IEEE80211_NODE_STAT_ADD(ni, ps_discard, discard); 261 } 262 return discard; 263 } 264 265 /* 266 * Handle a change in the PS station occupancy. 267 */ 268 static void 269 ieee80211_update_ps(struct ieee80211vap *vap, int nsta) 270 { 271 272 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP || 273 vap->iv_opmode == IEEE80211_M_IBSS, 274 ("operating mode %u", vap->iv_opmode)); 275 } 276 277 /* 278 * Indicate whether there are frames queued for a station in power-save mode. 279 */ 280 static int 281 ieee80211_set_tim(struct ieee80211_node *ni, int set) 282 { 283 struct ieee80211vap *vap = ni->ni_vap; 284 struct ieee80211com *ic = ni->ni_ic; 285 uint16_t aid; 286 int changed; 287 288 ic = ni->ni_ic; 289 KASSERT(vap->iv_opmode == IEEE80211_M_HOSTAP || 290 vap->iv_opmode == IEEE80211_M_IBSS, 291 ("operating mode %u", vap->iv_opmode)); 292 293 aid = IEEE80211_AID(ni->ni_associd); 294 KASSERT(aid < vap->iv_max_aid, 295 ("bogus aid %u, max %u", aid, vap->iv_max_aid)); 296 297 IEEE80211_LOCK(ic); 298 changed = (set != (isset(vap->iv_tim_bitmap, aid) != 0)); 299 if (changed) { 300 if (set) { 301 setbit(vap->iv_tim_bitmap, aid); 302 vap->iv_ps_pending++; 303 } else { 304 clrbit(vap->iv_tim_bitmap, aid); 305 vap->iv_ps_pending--; 306 } 307 /* NB: we know vap is in RUN state so no need to check */ 308 vap->iv_update_beacon(vap, IEEE80211_BEACON_TIM); 309 } 310 IEEE80211_UNLOCK(ic); 311 312 return changed; 313 } 314 315 /* 316 * Save an outbound packet for a node in power-save sleep state. 317 * The new packet is placed on the node's saved queue, and the TIM 318 * is changed, if necessary. 319 */ 320 int 321 ieee80211_pwrsave(struct ieee80211_node *ni, struct mbuf *m) 322 { 323 struct ieee80211_psq *psq = &ni->ni_psq; 324 struct ieee80211vap *vap = ni->ni_vap; 325 struct ieee80211com *ic = ni->ni_ic; 326 struct ieee80211_psq_head *qhead; 327 int qlen, age; 328 329 IEEE80211_PSQ_LOCK(psq); 330 if (psq->psq_len >= psq->psq_maxlen) { 331 psq->psq_drops++; 332 IEEE80211_PSQ_UNLOCK(psq); 333 IEEE80211_NOTE(vap, IEEE80211_MSG_ANY, ni, 334 "pwr save q overflow, drops %d (size %d)", 335 psq->psq_drops, psq->psq_len); 336 #ifdef IEEE80211_DEBUG 337 if (ieee80211_msg_dumppkts(vap)) 338 ieee80211_dump_pkt(ni->ni_ic, mtod(m, caddr_t), 339 m->m_len, -1, -1); 340 #endif 341 psq_mfree(m); 342 return ENOSPC; 343 } 344 /* 345 * Tag the frame with it's expiry time and insert it in 346 * the appropriate queue. The aging interval is 4 times 347 * the listen interval specified by the station. Frames 348 * that sit around too long are reclaimed using this 349 * information. 350 */ 351 /* TU -> secs. XXX handle overflow? */ 352 age = IEEE80211_TU_TO_MS((ni->ni_intval * ic->ic_bintval) << 2) / 1000; 353 /* 354 * Encapsulated frames go on the high priority queue, 355 * other stuff goes on the low priority queue. We use 356 * this to order frames returned out of the driver 357 * ahead of frames we collect in ieee80211_start. 358 */ 359 if (m->m_flags & M_ENCAP) 360 qhead = &psq->psq_head[0]; 361 else 362 qhead = &psq->psq_head[1]; 363 if (qhead->tail == NULL) { 364 struct mbuf *mh; 365 366 qhead->head = m; 367 /* 368 * Take care to adjust age when inserting the first 369 * frame of a queue and the other queue already has 370 * frames. We need to preserve the age difference 371 * relationship so ieee80211_node_psq_age works. 372 */ 373 if (qhead == &psq->psq_head[1]) { 374 mh = psq->psq_head[0].head; 375 if (mh != NULL) 376 age-= M_AGE_GET(mh); 377 } else { 378 mh = psq->psq_head[1].head; 379 if (mh != NULL) { 380 int nage = M_AGE_GET(mh) - age; 381 /* XXX is clamping to zero good 'nuf? */ 382 M_AGE_SET(mh, nage < 0 ? 0 : nage); 383 } 384 } 385 } else { 386 qhead->tail->m_nextpkt = m; 387 age -= M_AGE_GET(qhead->head); 388 } 389 KASSERT(age >= 0, ("age %d", age)); 390 M_AGE_SET(m, age); 391 m->m_nextpkt = NULL; 392 qhead->tail = m; 393 qhead->len++; 394 qlen = ++(psq->psq_len); 395 IEEE80211_PSQ_UNLOCK(psq); 396 397 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 398 "save frame with age %d, %u now queued", age, qlen); 399 400 if (qlen == 1 && vap->iv_set_tim != NULL) 401 vap->iv_set_tim(ni, 1); 402 403 return 0; 404 } 405 406 /* 407 * Move frames from the ps q to the vap's send queue 408 * and/or the driver's send queue; and kick the start 409 * method for each, as appropriate. Note we're careful 410 * to preserve packet ordering here. 411 */ 412 static void 413 pwrsave_flushq(struct ieee80211_node *ni) 414 { 415 struct ieee80211_psq *psq = &ni->ni_psq; 416 struct ieee80211vap *vap = ni->ni_vap; 417 struct ieee80211_psq_head *qhead; 418 struct ifnet *parent, *ifp; 419 420 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 421 "flush ps queue, %u packets queued", psq->psq_len); 422 423 IEEE80211_PSQ_LOCK(psq); 424 qhead = &psq->psq_head[0]; /* 802.11 frames */ 425 if (qhead->head != NULL) { 426 /* XXX could dispatch through vap and check M_ENCAP */ 427 parent = vap->iv_ic->ic_ifp; 428 /* XXX need different driver interface */ 429 /* XXX bypasses q max and OACTIVE */ 430 IF_PREPEND_LIST(&parent->if_snd, qhead->head, qhead->tail, 431 qhead->len); 432 qhead->head = qhead->tail = NULL; 433 qhead->len = 0; 434 } else 435 parent = NULL; 436 437 qhead = &psq->psq_head[1]; /* 802.3 frames */ 438 if (qhead->head != NULL) { 439 ifp = vap->iv_ifp; 440 /* XXX need different driver interface */ 441 /* XXX bypasses q max and OACTIVE */ 442 IF_PREPEND_LIST(&ifp->if_snd, qhead->head, qhead->tail, 443 qhead->len); 444 qhead->head = qhead->tail = NULL; 445 qhead->len = 0; 446 } else 447 ifp = NULL; 448 psq->psq_len = 0; 449 IEEE80211_PSQ_UNLOCK(psq); 450 451 /* NB: do this outside the psq lock */ 452 /* XXX packets might get reordered if parent is OACTIVE */ 453 if (parent != NULL) 454 parent->if_start(parent); 455 if (ifp != NULL) 456 ifp->if_start(ifp); 457 } 458 459 /* 460 * Handle station power-save state change. 461 */ 462 void 463 ieee80211_node_pwrsave(struct ieee80211_node *ni, int enable) 464 { 465 struct ieee80211vap *vap = ni->ni_vap; 466 int update; 467 468 update = 0; 469 if (enable) { 470 if ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) == 0) { 471 vap->iv_ps_sta++; 472 update = 1; 473 } 474 ni->ni_flags |= IEEE80211_NODE_PWR_MGT; 475 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 476 "power save mode on, %u sta's in ps mode", vap->iv_ps_sta); 477 478 if (update) 479 vap->iv_update_ps(vap, vap->iv_ps_sta); 480 } else { 481 if (ni->ni_flags & IEEE80211_NODE_PWR_MGT) { 482 vap->iv_ps_sta--; 483 update = 1; 484 } 485 ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT; 486 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 487 "power save mode off, %u sta's in ps mode", vap->iv_ps_sta); 488 489 /* NB: order here is intentional so TIM is clear before flush */ 490 if (vap->iv_set_tim != NULL) 491 vap->iv_set_tim(ni, 0); 492 if (update) { 493 /* NB if no sta's in ps, driver should flush mc q */ 494 vap->iv_update_ps(vap, vap->iv_ps_sta); 495 } 496 if (ni->ni_psq.psq_len != 0) 497 pwrsave_flushq(ni); 498 } 499 } 500 501 /* 502 * Handle power-save state change in station mode. 503 */ 504 void 505 ieee80211_sta_pwrsave(struct ieee80211vap *vap, int enable) 506 { 507 struct ieee80211_node *ni = vap->iv_bss; 508 509 if (!((enable != 0) ^ ((ni->ni_flags & IEEE80211_NODE_PWR_MGT) != 0))) 510 return; 511 512 IEEE80211_NOTE(vap, IEEE80211_MSG_POWER, ni, 513 "sta power save mode %s", enable ? "on" : "off"); 514 if (!enable) { 515 ni->ni_flags &= ~IEEE80211_NODE_PWR_MGT; 516 ieee80211_send_nulldata(ieee80211_ref_node(ni)); 517 /* 518 * Flush any queued frames; we can do this immediately 519 * because we know they'll be queued behind the null 520 * data frame we send the ap. 521 * XXX can we use a data frame to take us out of ps? 522 */ 523 if (ni->ni_psq.psq_len != 0) 524 pwrsave_flushq(ni); 525 } else { 526 ni->ni_flags |= IEEE80211_NODE_PWR_MGT; 527 ieee80211_send_nulldata(ieee80211_ref_node(ni)); 528 } 529 } 530