2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2012 Chelsio Communications, Inc.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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
28 #include <sys/cdefs.h>
30 #include "opt_inet6.h"
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>
39 #include <sys/mutex.h>
40 #include <sys/rwlock.h>
41 #include <sys/socket.h>
43 #include <netinet/in.h>
45 #include "common/common.h"
46 #include "common/t4_msg.h"
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.
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.
68 * Allocate a free L2T entry. Must be called with l2t_data.lock held.
71 t4_alloc_l2e(struct l2t_data *d)
73 struct l2t_entry *end, *e, **p;
75 rw_assert(&d->lock, RA_WLOCKED);
77 if (!atomic_load_acq_int(&d->nfree))
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)
85 for (e = d->l2tab; atomic_load_acq_int(&e->refcnt); ++e)
89 atomic_subtract_int(&d->nfree, 1);
92 * The entry we found may be an inactive entry that is
93 * presently in the hash table. We need to remove it.
95 if (e->state < L2T_STATE_SWITCHING) {
96 for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next) {
105 e->state = L2T_STATE_UNUSED;
109 static struct l2t_entry *
110 find_or_alloc_l2e(struct l2t_data *d, uint16_t vlan, uint8_t port, uint8_t *dmac)
112 struct l2t_entry *end, *e, **p;
113 struct l2t_entry *first_free = NULL;
115 for (e = &d->l2tab[0], end = &d->l2tab[d->l2t_size]; e != end; ++e) {
116 if (atomic_load_acq_int(&e->refcnt) == 0) {
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. */
125 if (first_free == NULL)
126 return (NULL); /* No match and no room for a new entry. */
129 * The entry we found may be an inactive entry that is
130 * presently in the hash table. We need to remove it.
133 if (e->state < L2T_STATE_SWITCHING) {
134 for (p = &d->l2tab[e->hash].first; *p; p = &(*p)->next) {
142 e->state = L2T_STATE_UNUSED;
147 mk_write_l2e(struct adapter *sc, struct l2t_entry *e, int sync, int reply,
150 struct cpl_l2t_write_req *req;
154 idx = e->idx + sc->vres.l2t.start;
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));
165 * Write an L2T entry. Must be called with the entry locked.
166 * The write may be synchronous or asynchronous.
169 t4_write_l2e(struct l2t_entry *e, int sync)
173 struct wrq_cookie cookie;
174 struct cpl_l2t_write_req *req;
176 mtx_assert(&e->lock, MA_OWNED);
177 MPASS(e->wrq != NULL);
182 req = start_wrq_wr(wrq, howmany(sizeof(*req), 16), &cookie);
186 mk_write_l2e(sc, e, sync, sync, req);
188 commit_wrq_wr(wrq, req, &cookie);
190 if (sync && e->state != L2T_STATE_SWITCHING)
191 e->state = L2T_STATE_SYNC_WRITE;
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.
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'
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.
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)
217 TXQ_LOCK_ASSERT_OWNED(txq);
224 /* First, try to find an existing entry. */
225 for (i = 0; i < d->l2t_size; i++) {
227 if (e->state != L2T_STATE_TLS)
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) {
234 * This entry wasn't held but is still
235 * valid, so decrement nfree.
237 atomic_subtract_int(&d->nfree, 1);
239 KASSERT(e->refcnt > 0,
240 ("%s: refcount overflow", __func__));
241 rw_runlock(&d->lock);
247 * Don't bother rechecking if the upgrade fails since the txq is
250 if (!rw_try_upgrade(&d->lock)) {
251 rw_runlock(&d->lock);
255 /* Match not found, allocate a new entry. */
258 rw_wunlock(&d->lock);
262 /* Initialize the entry. */
263 e->state = L2T_STATE_TLS;
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);
272 /* Write out the work request. */
273 *ndesc = howmany(sizeof(struct cpl_l2t_write_req), EQ_ESIZE);
275 mk_write_l2e(sc, e, 1, 0, dst);
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.
286 t4_l2t_alloc_switching(struct adapter *sc, uint16_t vlan, uint8_t port,
289 struct l2t_data *d = sc->l2t;
294 e = find_or_alloc_l2e(d, vlan, port, eth_addr);
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;
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);
311 MPASS(e->vlan == vlan);
312 MPASS(e->lport == port);
313 atomic_add_int(&e->refcnt, 1);
316 rw_wunlock(&d->lock);
321 t4_init_l2t(struct adapter *sc, int flags)
326 l2t_size = sc->vres.l2t.size;
327 if (l2t_size < 2) /* At least 1 bucket for IP and 1 for IPv6 */
330 d = malloc(sizeof(*d) + l2t_size * sizeof (struct l2t_entry), M_CXGBE,
335 d->l2t_size = l2t_size;
337 atomic_store_rel_int(&d->nfree, l2t_size);
338 rw_init(&d->lock, "L2T");
340 for (i = 0; i < l2t_size; i++) {
341 struct l2t_entry *e = &d->l2tab[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);
356 t4_free_l2t(struct l2t_data *d)
360 for (i = 0; i < d->l2t_size; i++)
361 mtx_destroy(&d->l2tab[i].lock);
362 rw_destroy(&d->lock);
369 do_l2t_write_rpl(struct sge_iq *iq, const struct rss_header *rss,
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;
376 if (__predict_false(rpl->status != CPL_ERR_NONE)) {
378 "Unexpected L2T_WRITE_RPL (%u) for entry at hw_idx %u\n",
386 static inline unsigned int
387 vlan_prio(const struct l2t_entry *e)
389 return e->vlan >> 13;
393 l2e_state(const struct l2t_entry *e)
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';
407 sysctl_l2t(SYSCTL_HANDLER_ARGS)
409 struct adapter *sc = arg1;
410 struct l2t_data *l2t = sc->l2t;
413 int rc, i, header = 0;
414 char ip[INET6_ADDRSTRLEN];
419 rc = sysctl_wire_old_buffer(req, 0);
423 sb = sbuf_new_for_sysctl(NULL, NULL, 4096, req);
428 for (i = 0; i < l2t->l2t_size; i++, e++) {
430 if (e->state == L2T_STATE_UNUSED)
434 sbuf_printf(sb, " Idx IP address "
435 "Ethernet address VLAN/P LP State Users Port");
438 if (e->state >= L2T_STATE_SWITCHING)
441 inet_ntop(e->ipv6 ? AF_INET6 : AF_INET, &e->addr[0],
446 * XXX: IPv6 addresses may not align properly in the output.
448 sbuf_printf(sb, "\n%4u %-15s %02x:%02x:%02x:%02x:%02x:%02x %4d"
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) : "-");
456 mtx_unlock(&e->lock);
459 rc = sbuf_finish(sb);