1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2012 Chelsio Communications, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #include <sys/cdefs.h> 29 #include "opt_inet.h" 30 #include "opt_inet6.h" 31 32 #include <sys/param.h> 33 #include <sys/eventhandler.h> 34 #include <sys/systm.h> 35 #include <sys/kernel.h> 36 #include <sys/module.h> 37 #include <sys/bus.h> 38 #include <sys/lock.h> 39 #include <sys/mutex.h> 40 #include <sys/rwlock.h> 41 #include <sys/socket.h> 42 #include <sys/sbuf.h> 43 #include <netinet/in.h> 44 45 #include "common/common.h" 46 #include "common/t4_msg.h" 47 #include "t4_l2t.h" 48 49 /* 50 * Module locking notes: There is a RW lock protecting the L2 table as a 51 * whole plus a spinlock per L2T entry. Entry lookups and allocations happen 52 * under the protection of the table lock, individual entry changes happen 53 * while holding that entry's spinlock. The table lock nests outside the 54 * entry locks. Allocations of new entries take the table lock as writers so 55 * no other lookups can happen while allocating new entries. Entry updates 56 * take the table lock as readers so multiple entries can be updated in 57 * parallel. An L2T entry can be dropped by decrementing its reference count 58 * and therefore can happen in parallel with entry allocation but no entry 59 * can change state or increment its ref count during allocation as both of 60 * these perform lookups. 61 * 62 * Note: We do not take references to ifnets in this module because both 63 * the TOE and the sockets already hold references to the interfaces and the 64 * lifetime of an L2T entry is fully contained in the lifetime of the TOE. 65 */ 66 67 /* 68 * Allocate a free L2T entry. Must be called with l2t_data.lock held. 69 */ 70 struct l2t_entry * 71 t4_alloc_l2e(struct l2t_data *d) 72 { 73 struct l2t_entry *end, *e, **p; 74 75 rw_assert(&d->lock, RA_WLOCKED); 76 if (__predict_false(d->l2t_stopped)) 77 return (NULL); 78 if (!atomic_load_acq_int(&d->nfree)) 79 return (NULL); 80 81 /* there's definitely a free entry */ 82 for (e = d->rover, end = &d->l2tab[d->l2t_size]; e != end; ++e) 83 if (atomic_load_acq_int(&e->refcnt) == 0) 84 goto found; 85 86 for (e = d->l2tab; atomic_load_acq_int(&e->refcnt); ++e) 87 continue; 88 found: 89 d->rover = e + 1; 90 atomic_subtract_int(&d->nfree, 1); 91 92 /* 93 * The entry we found may be an inactive entry that is 94 * presently in the hash table. We need to remove it. 95 */ 96 if (e->state < L2T_STATE_SWITCHING) { 97 for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next) { 98 if (*p == e) { 99 *p = e->next; 100 e->next = NULL; 101 break; 102 } 103 } 104 } 105 106 e->state = L2T_STATE_UNUSED; 107 return (e); 108 } 109 110 static struct l2t_entry * 111 find_or_alloc_l2e(struct l2t_data *d, uint16_t vlan, uint8_t port, uint8_t *dmac) 112 { 113 struct l2t_entry *end, *e, **p; 114 struct l2t_entry *first_free = NULL; 115 116 for (e = &d->l2tab[0], end = &d->l2tab[d->l2t_size]; e != end; ++e) { 117 if (atomic_load_acq_int(&e->refcnt) == 0) { 118 if (!first_free) 119 first_free = e; 120 } else if (e->state == L2T_STATE_SWITCHING && 121 memcmp(e->dmac, dmac, ETHER_ADDR_LEN) == 0 && 122 e->vlan == vlan && e->lport == port) 123 return (e); /* Found existing entry that matches. */ 124 } 125 126 if (first_free == NULL) 127 return (NULL); /* No match and no room for a new entry. */ 128 129 /* 130 * The entry we found may be an inactive entry that is 131 * presently in the hash table. We need to remove it. 132 */ 133 e = first_free; 134 if (e->state < L2T_STATE_SWITCHING) { 135 for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next) { 136 if (*p == e) { 137 *p = e->next; 138 e->next = NULL; 139 break; 140 } 141 } 142 } 143 e->state = L2T_STATE_UNUSED; 144 return (e); 145 } 146 147 static void 148 mk_write_l2e(struct adapter *sc, struct l2t_entry *e, int sync, int reply, 149 void *dst) 150 { 151 struct cpl_l2t_write_req *req; 152 int idx; 153 154 req = dst; 155 idx = e->idx + sc->vres.l2t.start; 156 INIT_TP_WR(req, 0); 157 OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, idx | 158 V_SYNC_WR(sync) | V_TID_QID(e->iqid))); 159 req->params = htons(V_L2T_W_PORT(e->lport) | V_L2T_W_NOREPLY(!reply)); 160 req->l2t_idx = htons(idx); 161 req->vlan = htons(e->vlan); 162 memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac)); 163 } 164 165 /* 166 * Write an L2T entry. Must be called with the entry locked. 167 * The write may be synchronous or asynchronous. 168 */ 169 int 170 t4_write_l2e(struct l2t_entry *e, int sync) 171 { 172 struct sge_wrq *wrq; 173 struct adapter *sc; 174 struct wrq_cookie cookie; 175 struct cpl_l2t_write_req *req; 176 177 mtx_assert(&e->lock, MA_OWNED); 178 MPASS(e->wrq != NULL); 179 180 wrq = e->wrq; 181 sc = wrq->adapter; 182 183 req = start_wrq_wr(wrq, howmany(sizeof(*req), 16), &cookie); 184 if (req == NULL) 185 return (ENOMEM); 186 187 mk_write_l2e(sc, e, sync, sync, req); 188 189 commit_wrq_wr(wrq, req, &cookie); 190 191 if (sync && e->state != L2T_STATE_SWITCHING) 192 e->state = L2T_STATE_SYNC_WRITE; 193 194 return (0); 195 } 196 197 /* 198 * Allocate an L2T entry for use by a TLS connection. These entries are 199 * associated with a specific VLAN and destination MAC that never changes. 200 * However, multiple TLS connections might share a single entry. 201 * 202 * If a new L2T entry is allocated, a work request to initialize it is 203 * written to 'txq' and 'ndesc' will be set to 1. Otherwise, 'ndesc' 204 * will be set to 0. 205 * 206 * To avoid races, separate L2T entries are reserved for individual 207 * queues since the L2T entry update is written to a txq just prior to 208 * TLS work requests that will depend on it being written. 209 */ 210 struct l2t_entry * 211 t4_l2t_alloc_tls(struct adapter *sc, struct sge_txq *txq, void *dst, 212 int *ndesc, uint16_t vlan, uint8_t port, uint8_t *eth_addr) 213 { 214 struct l2t_data *d; 215 struct l2t_entry *e; 216 int i; 217 218 TXQ_LOCK_ASSERT_OWNED(txq); 219 220 d = sc->l2t; 221 *ndesc = 0; 222 223 rw_rlock(&d->lock); 224 225 /* First, try to find an existing entry. */ 226 for (i = 0; i < d->l2t_size; i++) { 227 e = &d->l2tab[i]; 228 if (e->state != L2T_STATE_TLS) 229 continue; 230 if (e->vlan == vlan && e->lport == port && 231 e->wrq == (struct sge_wrq *)txq && 232 memcmp(e->dmac, eth_addr, ETHER_ADDR_LEN) == 0) { 233 if (atomic_fetchadd_int(&e->refcnt, 1) == 0) { 234 /* 235 * This entry wasn't held but is still 236 * valid, so decrement nfree. 237 */ 238 atomic_subtract_int(&d->nfree, 1); 239 } 240 KASSERT(e->refcnt > 0, 241 ("%s: refcount overflow", __func__)); 242 rw_runlock(&d->lock); 243 return (e); 244 } 245 } 246 247 /* 248 * Don't bother rechecking if the upgrade fails since the txq is 249 * already locked. 250 */ 251 if (!rw_try_upgrade(&d->lock)) { 252 rw_runlock(&d->lock); 253 rw_wlock(&d->lock); 254 } 255 256 /* Match not found, allocate a new entry. */ 257 e = t4_alloc_l2e(d); 258 if (e == NULL) { 259 rw_wunlock(&d->lock); 260 return (e); 261 } 262 263 /* Initialize the entry. */ 264 e->state = L2T_STATE_TLS; 265 e->vlan = vlan; 266 e->lport = port; 267 e->iqid = sc->sge.fwq.abs_id; 268 e->wrq = (struct sge_wrq *)txq; 269 memcpy(e->dmac, eth_addr, ETHER_ADDR_LEN); 270 atomic_store_rel_int(&e->refcnt, 1); 271 rw_wunlock(&d->lock); 272 273 /* Write out the work request. */ 274 *ndesc = howmany(sizeof(struct cpl_l2t_write_req), EQ_ESIZE); 275 MPASS(*ndesc == 1); 276 mk_write_l2e(sc, e, 1, 0, dst); 277 278 return (e); 279 } 280 281 /* 282 * Allocate an L2T entry for use by a switching rule. Such need to be 283 * explicitly freed and while busy they are not on any hash chain, so normal 284 * address resolution updates do not see them. 285 */ 286 struct l2t_entry * 287 t4_l2t_alloc_switching(struct adapter *sc, uint16_t vlan, uint8_t port, 288 uint8_t *eth_addr) 289 { 290 struct l2t_data *d = sc->l2t; 291 struct l2t_entry *e; 292 int rc; 293 294 rw_wlock(&d->lock); 295 if (__predict_false(d->l2t_stopped)) 296 e = NULL; 297 else 298 e = find_or_alloc_l2e(d, vlan, port, eth_addr); 299 if (e) { 300 if (atomic_load_acq_int(&e->refcnt) == 0) { 301 mtx_lock(&e->lock); /* avoid race with t4_l2t_free */ 302 e->wrq = &sc->sge.ctrlq[0]; 303 e->iqid = sc->sge.fwq.abs_id; 304 e->state = L2T_STATE_SWITCHING; 305 e->vlan = vlan; 306 e->lport = port; 307 memcpy(e->dmac, eth_addr, ETHER_ADDR_LEN); 308 atomic_store_rel_int(&e->refcnt, 1); 309 atomic_subtract_int(&d->nfree, 1); 310 rc = t4_write_l2e(e, 0); 311 mtx_unlock(&e->lock); 312 if (rc != 0) 313 e = NULL; 314 } else { 315 MPASS(e->vlan == vlan); 316 MPASS(e->lport == port); 317 atomic_add_int(&e->refcnt, 1); 318 } 319 } 320 rw_wunlock(&d->lock); 321 return (e); 322 } 323 324 int 325 t4_init_l2t(struct adapter *sc, int flags) 326 { 327 int i, l2t_size; 328 struct l2t_data *d; 329 330 l2t_size = sc->vres.l2t.size; 331 if (l2t_size < 2) /* At least 1 bucket for IP and 1 for IPv6 */ 332 return (EINVAL); 333 334 d = malloc(sizeof(*d) + l2t_size * sizeof (struct l2t_entry), M_CXGBE, 335 M_ZERO | flags); 336 if (!d) 337 return (ENOMEM); 338 339 d->l2t_size = l2t_size; 340 d->l2t_stopped = false; 341 d->rover = d->l2tab; 342 atomic_store_rel_int(&d->nfree, l2t_size); 343 rw_init(&d->lock, "L2T"); 344 345 for (i = 0; i < l2t_size; i++) { 346 struct l2t_entry *e = &d->l2tab[i]; 347 348 e->idx = i; 349 e->state = L2T_STATE_UNUSED; 350 mtx_init(&e->lock, "L2T_E", NULL, MTX_DEF); 351 STAILQ_INIT(&e->wr_list); 352 atomic_store_rel_int(&e->refcnt, 0); 353 } 354 355 sc->l2t = d; 356 357 return (0); 358 } 359 360 int 361 t4_free_l2t(struct adapter *sc) 362 { 363 struct l2t_data *d = sc->l2t; 364 int i; 365 366 for (i = 0; i < d->l2t_size; i++) 367 mtx_destroy(&d->l2tab[i].lock); 368 rw_destroy(&d->lock); 369 free(d, M_CXGBE); 370 371 return (0); 372 } 373 374 int 375 t4_stop_l2t(struct adapter *sc) 376 { 377 struct l2t_data *d = sc->l2t; 378 379 rw_wlock(&d->lock); 380 d->l2t_stopped = true; 381 rw_wunlock(&d->lock); 382 383 return (0); 384 } 385 386 int 387 t4_restart_l2t(struct adapter *sc) 388 { 389 struct l2t_data *d = sc->l2t; 390 391 rw_wlock(&d->lock); 392 d->l2t_stopped = false; 393 rw_wunlock(&d->lock); 394 395 return (0); 396 } 397 398 int 399 do_l2t_write_rpl(struct sge_iq *iq, const struct rss_header *rss, 400 struct mbuf *m) 401 { 402 struct adapter *sc = iq->adapter; 403 const struct cpl_l2t_write_rpl *rpl = (const void *)(rss + 1); 404 const u_int hwidx = GET_TID(rpl) & ~(F_SYNC_WR | V_TID_QID(M_TID_QID)); 405 const bool sync = GET_TID(rpl) & F_SYNC_WR; 406 407 MPASS(iq->abs_id == G_TID_QID(GET_TID(rpl))); 408 409 if (__predict_false(hwidx < sc->vres.l2t.start) || 410 __predict_false(hwidx >= sc->vres.l2t.start + sc->vres.l2t.size) || 411 __predict_false(rpl->status != CPL_ERR_NONE)) { 412 CH_ERR(sc, "%s: hwidx %u, rpl %u, sync %u; L2T st %u, sz %u\n", 413 __func__, hwidx, rpl->status, sync, sc->vres.l2t.start, 414 sc->vres.l2t.size); 415 return (EINVAL); 416 } 417 418 return (0); 419 } 420 421 static inline unsigned int 422 vlan_prio(const struct l2t_entry *e) 423 { 424 return e->vlan >> 13; 425 } 426 427 static char 428 l2e_state(const struct l2t_entry *e) 429 { 430 switch (e->state) { 431 case L2T_STATE_VALID: return 'V'; /* valid, fast-path entry */ 432 case L2T_STATE_STALE: return 'S'; /* needs revalidation, but usable */ 433 case L2T_STATE_SYNC_WRITE: return 'W'; 434 case L2T_STATE_RESOLVING: return STAILQ_EMPTY(&e->wr_list) ? 'R' : 'A'; 435 case L2T_STATE_SWITCHING: return 'X'; 436 case L2T_STATE_TLS: return 'T'; 437 default: return 'U'; 438 } 439 } 440 441 int 442 sysctl_l2t(SYSCTL_HANDLER_ARGS) 443 { 444 struct adapter *sc = arg1; 445 struct l2t_data *l2t = sc->l2t; 446 struct l2t_entry *e; 447 struct sbuf *sb; 448 int rc, i, header = 0; 449 char ip[INET6_ADDRSTRLEN]; 450 451 if (l2t == NULL) 452 return (ENXIO); 453 454 rc = sysctl_wire_old_buffer(req, 0); 455 if (rc != 0) 456 return (rc); 457 458 sb = sbuf_new_for_sysctl(NULL, NULL, 4096, req); 459 if (sb == NULL) 460 return (ENOMEM); 461 462 e = &l2t->l2tab[0]; 463 for (i = 0; i < l2t->l2t_size; i++, e++) { 464 mtx_lock(&e->lock); 465 if (e->state == L2T_STATE_UNUSED) 466 goto skip; 467 468 if (header == 0) { 469 sbuf_printf(sb, " Idx IP address " 470 "Ethernet address VLAN/P LP State Users Port"); 471 header = 1; 472 } 473 if (e->state >= L2T_STATE_SWITCHING) 474 ip[0] = 0; 475 else { 476 inet_ntop(e->ipv6 ? AF_INET6 : AF_INET, &e->addr[0], 477 &ip[0], sizeof(ip)); 478 } 479 480 /* 481 * XXX: IPv6 addresses may not align properly in the output. 482 */ 483 sbuf_printf(sb, "\n%4u %-15s %02x:%02x:%02x:%02x:%02x:%02x %4d" 484 " %u %2u %c %5u %s", 485 e->idx, ip, e->dmac[0], e->dmac[1], e->dmac[2], 486 e->dmac[3], e->dmac[4], e->dmac[5], 487 e->vlan & 0xfff, vlan_prio(e), e->lport, 488 l2e_state(e), atomic_load_acq_int(&e->refcnt), 489 e->ifp ? if_name(e->ifp) : "-"); 490 skip: 491 mtx_unlock(&e->lock); 492 } 493 494 rc = sbuf_finish(sb); 495 sbuf_delete(sb); 496 497 return (rc); 498 } 499