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 77 if (!atomic_load_acq_int(&d->nfree)) 78 return (NULL); 79 80 /* there's definitely a free entry */ 81 for (e = d->rover, end = &d->l2tab[d->l2t_size]; e != end; ++e) 82 if (atomic_load_acq_int(&e->refcnt) == 0) 83 goto found; 84 85 for (e = d->l2tab; atomic_load_acq_int(&e->refcnt); ++e) 86 continue; 87 found: 88 d->rover = e + 1; 89 atomic_subtract_int(&d->nfree, 1); 90 91 /* 92 * The entry we found may be an inactive entry that is 93 * presently in the hash table. We need to remove it. 94 */ 95 if (e->state < L2T_STATE_SWITCHING) { 96 for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next) { 97 if (*p == e) { 98 *p = e->next; 99 e->next = NULL; 100 break; 101 } 102 } 103 } 104 105 e->state = L2T_STATE_UNUSED; 106 return (e); 107 } 108 109 static struct l2t_entry * 110 find_or_alloc_l2e(struct l2t_data *d, uint16_t vlan, uint8_t port, uint8_t *dmac) 111 { 112 struct l2t_entry *end, *e, **p; 113 struct l2t_entry *first_free = NULL; 114 115 for (e = &d->l2tab[0], end = &d->l2tab[d->l2t_size]; e != end; ++e) { 116 if (atomic_load_acq_int(&e->refcnt) == 0) { 117 if (!first_free) 118 first_free = e; 119 } else if (e->state == L2T_STATE_SWITCHING && 120 memcmp(e->dmac, dmac, ETHER_ADDR_LEN) == 0 && 121 e->vlan == vlan && e->lport == port) 122 return (e); /* Found existing entry that matches. */ 123 } 124 125 if (first_free == NULL) 126 return (NULL); /* No match and no room for a new entry. */ 127 128 /* 129 * The entry we found may be an inactive entry that is 130 * presently in the hash table. We need to remove it. 131 */ 132 e = first_free; 133 if (e->state < L2T_STATE_SWITCHING) { 134 for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next) { 135 if (*p == e) { 136 *p = e->next; 137 e->next = NULL; 138 break; 139 } 140 } 141 } 142 e->state = L2T_STATE_UNUSED; 143 return (e); 144 } 145 146 static void 147 mk_write_l2e(struct adapter *sc, struct l2t_entry *e, int sync, int reply, 148 void *dst) 149 { 150 struct cpl_l2t_write_req *req; 151 int idx; 152 153 req = dst; 154 idx = e->idx + sc->vres.l2t.start; 155 INIT_TP_WR(req, 0); 156 OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, idx | 157 V_SYNC_WR(sync) | V_TID_QID(e->iqid))); 158 req->params = htons(V_L2T_W_PORT(e->lport) | V_L2T_W_NOREPLY(!reply)); 159 req->l2t_idx = htons(idx); 160 req->vlan = htons(e->vlan); 161 memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac)); 162 } 163 164 /* 165 * Write an L2T entry. Must be called with the entry locked. 166 * The write may be synchronous or asynchronous. 167 */ 168 int 169 t4_write_l2e(struct l2t_entry *e, int sync) 170 { 171 struct sge_wrq *wrq; 172 struct adapter *sc; 173 struct wrq_cookie cookie; 174 struct cpl_l2t_write_req *req; 175 176 mtx_assert(&e->lock, MA_OWNED); 177 MPASS(e->wrq != NULL); 178 179 wrq = e->wrq; 180 sc = wrq->adapter; 181 182 req = start_wrq_wr(wrq, howmany(sizeof(*req), 16), &cookie); 183 if (req == NULL) 184 return (ENOMEM); 185 186 mk_write_l2e(sc, e, sync, sync, req); 187 188 commit_wrq_wr(wrq, req, &cookie); 189 190 if (sync && e->state != L2T_STATE_SWITCHING) 191 e->state = L2T_STATE_SYNC_WRITE; 192 193 return (0); 194 } 195 196 /* 197 * Allocate an L2T entry for use by a TLS connection. These entries are 198 * associated with a specific VLAN and destination MAC that never changes. 199 * However, multiple TLS connections might share a single entry. 200 * 201 * If a new L2T entry is allocated, a work request to initialize it is 202 * written to 'txq' and 'ndesc' will be set to 1. Otherwise, 'ndesc' 203 * will be set to 0. 204 * 205 * To avoid races, separate L2T entries are reserved for individual 206 * queues since the L2T entry update is written to a txq just prior to 207 * TLS work requests that will depend on it being written. 208 */ 209 struct l2t_entry * 210 t4_l2t_alloc_tls(struct adapter *sc, struct sge_txq *txq, void *dst, 211 int *ndesc, uint16_t vlan, uint8_t port, uint8_t *eth_addr) 212 { 213 struct l2t_data *d; 214 struct l2t_entry *e; 215 int i; 216 217 TXQ_LOCK_ASSERT_OWNED(txq); 218 219 d = sc->l2t; 220 *ndesc = 0; 221 222 rw_rlock(&d->lock); 223 224 /* First, try to find an existing entry. */ 225 for (i = 0; i < d->l2t_size; i++) { 226 e = &d->l2tab[i]; 227 if (e->state != L2T_STATE_TLS) 228 continue; 229 if (e->vlan == vlan && e->lport == port && 230 e->wrq == (struct sge_wrq *)txq && 231 memcmp(e->dmac, eth_addr, ETHER_ADDR_LEN) == 0) { 232 if (atomic_fetchadd_int(&e->refcnt, 1) == 0) { 233 /* 234 * This entry wasn't held but is still 235 * valid, so decrement nfree. 236 */ 237 atomic_subtract_int(&d->nfree, 1); 238 } 239 KASSERT(e->refcnt > 0, 240 ("%s: refcount overflow", __func__)); 241 rw_runlock(&d->lock); 242 return (e); 243 } 244 } 245 246 /* 247 * Don't bother rechecking if the upgrade fails since the txq is 248 * already locked. 249 */ 250 if (!rw_try_upgrade(&d->lock)) { 251 rw_runlock(&d->lock); 252 rw_wlock(&d->lock); 253 } 254 255 /* Match not found, allocate a new entry. */ 256 e = t4_alloc_l2e(d); 257 if (e == NULL) { 258 rw_wunlock(&d->lock); 259 return (e); 260 } 261 262 /* Initialize the entry. */ 263 e->state = L2T_STATE_TLS; 264 e->vlan = vlan; 265 e->lport = port; 266 e->iqid = sc->sge.fwq.abs_id; 267 e->wrq = (struct sge_wrq *)txq; 268 memcpy(e->dmac, eth_addr, ETHER_ADDR_LEN); 269 atomic_store_rel_int(&e->refcnt, 1); 270 rw_wunlock(&d->lock); 271 272 /* Write out the work request. */ 273 *ndesc = howmany(sizeof(struct cpl_l2t_write_req), EQ_ESIZE); 274 MPASS(*ndesc == 1); 275 mk_write_l2e(sc, e, 1, 0, dst); 276 277 return (e); 278 } 279 280 /* 281 * Allocate an L2T entry for use by a switching rule. Such need to be 282 * explicitly freed and while busy they are not on any hash chain, so normal 283 * address resolution updates do not see them. 284 */ 285 struct l2t_entry * 286 t4_l2t_alloc_switching(struct adapter *sc, uint16_t vlan, uint8_t port, 287 uint8_t *eth_addr) 288 { 289 struct l2t_data *d = sc->l2t; 290 struct l2t_entry *e; 291 int rc; 292 293 rw_wlock(&d->lock); 294 e = find_or_alloc_l2e(d, vlan, port, eth_addr); 295 if (e) { 296 if (atomic_load_acq_int(&e->refcnt) == 0) { 297 mtx_lock(&e->lock); /* avoid race with t4_l2t_free */ 298 e->wrq = &sc->sge.ctrlq[0]; 299 e->iqid = sc->sge.fwq.abs_id; 300 e->state = L2T_STATE_SWITCHING; 301 e->vlan = vlan; 302 e->lport = port; 303 memcpy(e->dmac, eth_addr, ETHER_ADDR_LEN); 304 atomic_store_rel_int(&e->refcnt, 1); 305 atomic_subtract_int(&d->nfree, 1); 306 rc = t4_write_l2e(e, 0); 307 mtx_unlock(&e->lock); 308 if (rc != 0) 309 e = NULL; 310 } else { 311 MPASS(e->vlan == vlan); 312 MPASS(e->lport == port); 313 atomic_add_int(&e->refcnt, 1); 314 } 315 } 316 rw_wunlock(&d->lock); 317 return (e); 318 } 319 320 int 321 t4_init_l2t(struct adapter *sc, int flags) 322 { 323 int i, l2t_size; 324 struct l2t_data *d; 325 326 l2t_size = sc->vres.l2t.size; 327 if (l2t_size < 2) /* At least 1 bucket for IP and 1 for IPv6 */ 328 return (EINVAL); 329 330 d = malloc(sizeof(*d) + l2t_size * sizeof (struct l2t_entry), M_CXGBE, 331 M_ZERO | flags); 332 if (!d) 333 return (ENOMEM); 334 335 d->l2t_size = l2t_size; 336 d->rover = d->l2tab; 337 atomic_store_rel_int(&d->nfree, l2t_size); 338 rw_init(&d->lock, "L2T"); 339 340 for (i = 0; i < l2t_size; i++) { 341 struct l2t_entry *e = &d->l2tab[i]; 342 343 e->idx = i; 344 e->state = L2T_STATE_UNUSED; 345 mtx_init(&e->lock, "L2T_E", NULL, MTX_DEF); 346 STAILQ_INIT(&e->wr_list); 347 atomic_store_rel_int(&e->refcnt, 0); 348 } 349 350 sc->l2t = d; 351 352 return (0); 353 } 354 355 int 356 t4_free_l2t(struct l2t_data *d) 357 { 358 int i; 359 360 for (i = 0; i < d->l2t_size; i++) 361 mtx_destroy(&d->l2tab[i].lock); 362 rw_destroy(&d->lock); 363 free(d, M_CXGBE); 364 365 return (0); 366 } 367 368 int 369 do_l2t_write_rpl(struct sge_iq *iq, const struct rss_header *rss, 370 struct mbuf *m) 371 { 372 const struct cpl_l2t_write_rpl *rpl = (const void *)(rss + 1); 373 unsigned int tid = GET_TID(rpl); 374 unsigned int idx = tid % L2T_SIZE; 375 376 if (__predict_false(rpl->status != CPL_ERR_NONE)) { 377 log(LOG_ERR, 378 "Unexpected L2T_WRITE_RPL (%u) for entry at hw_idx %u\n", 379 rpl->status, idx); 380 return (EINVAL); 381 } 382 383 return (0); 384 } 385 386 static inline unsigned int 387 vlan_prio(const struct l2t_entry *e) 388 { 389 return e->vlan >> 13; 390 } 391 392 static char 393 l2e_state(const struct l2t_entry *e) 394 { 395 switch (e->state) { 396 case L2T_STATE_VALID: return 'V'; /* valid, fast-path entry */ 397 case L2T_STATE_STALE: return 'S'; /* needs revalidation, but usable */ 398 case L2T_STATE_SYNC_WRITE: return 'W'; 399 case L2T_STATE_RESOLVING: return STAILQ_EMPTY(&e->wr_list) ? 'R' : 'A'; 400 case L2T_STATE_SWITCHING: return 'X'; 401 case L2T_STATE_TLS: return 'T'; 402 default: return 'U'; 403 } 404 } 405 406 int 407 sysctl_l2t(SYSCTL_HANDLER_ARGS) 408 { 409 struct adapter *sc = arg1; 410 struct l2t_data *l2t = sc->l2t; 411 struct l2t_entry *e; 412 struct sbuf *sb; 413 int rc, i, header = 0; 414 char ip[INET6_ADDRSTRLEN]; 415 416 if (l2t == NULL) 417 return (ENXIO); 418 419 rc = sysctl_wire_old_buffer(req, 0); 420 if (rc != 0) 421 return (rc); 422 423 sb = sbuf_new_for_sysctl(NULL, NULL, 4096, req); 424 if (sb == NULL) 425 return (ENOMEM); 426 427 e = &l2t->l2tab[0]; 428 for (i = 0; i < l2t->l2t_size; i++, e++) { 429 mtx_lock(&e->lock); 430 if (e->state == L2T_STATE_UNUSED) 431 goto skip; 432 433 if (header == 0) { 434 sbuf_printf(sb, " Idx IP address " 435 "Ethernet address VLAN/P LP State Users Port"); 436 header = 1; 437 } 438 if (e->state >= L2T_STATE_SWITCHING) 439 ip[0] = 0; 440 else { 441 inet_ntop(e->ipv6 ? AF_INET6 : AF_INET, &e->addr[0], 442 &ip[0], sizeof(ip)); 443 } 444 445 /* 446 * XXX: IPv6 addresses may not align properly in the output. 447 */ 448 sbuf_printf(sb, "\n%4u %-15s %02x:%02x:%02x:%02x:%02x:%02x %4d" 449 " %u %2u %c %5u %s", 450 e->idx, ip, e->dmac[0], e->dmac[1], e->dmac[2], 451 e->dmac[3], e->dmac[4], e->dmac[5], 452 e->vlan & 0xfff, vlan_prio(e), e->lport, 453 l2e_state(e), atomic_load_acq_int(&e->refcnt), 454 e->ifp ? if_name(e->ifp) : "-"); 455 skip: 456 mtx_unlock(&e->lock); 457 } 458 459 rc = sbuf_finish(sb); 460 sbuf_delete(sb); 461 462 return (rc); 463 } 464