1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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__FBSDID("$FreeBSD$");
30
31#include "opt_inet.h"
32#include "opt_inet6.h"
33
34#ifdef TCP_OFFLOAD
35#include <sys/param.h>
36#include <sys/systm.h>
37#include <sys/kernel.h>
38#include <sys/module.h>
39#include <sys/bus.h>
40#include <sys/fnv_hash.h>
41#include <sys/lock.h>
42#include <sys/mutex.h>
43#include <sys/rwlock.h>
44#include <sys/socket.h>
45#include <sys/sbuf.h>
46#include <sys/taskqueue.h>
47#include <net/if.h>
48#include <net/if_types.h>
49#include <net/ethernet.h>
50#include <net/if_vlan_var.h>
51#include <net/route.h>
52#include <netinet/in.h>
53#include <netinet/toecore.h>
54
55#include "common/common.h"
56#include "common/t4_msg.h"
57#include "tom/t4_tom_l2t.h"
58#include "tom/t4_tom.h"
59
60#define VLAN_NONE	0xfff
61
62static inline void
63l2t_hold(struct l2t_data *d, struct l2t_entry *e)
64{
65
66	if (atomic_fetchadd_int(&e->refcnt, 1) == 0)  /* 0 -> 1 transition */
67		atomic_subtract_int(&d->nfree, 1);
68}
69
70static inline u_int
71l2_hash(struct l2t_data *d, const struct sockaddr *sa, int ifindex)
72{
73	u_int hash, half = d->l2t_size / 2, start = 0;
74	const void *key;
75	size_t len;
76
77	KASSERT(sa->sa_family == AF_INET || sa->sa_family == AF_INET6,
78	    ("%s: sa %p has unexpected sa_family %d", __func__, sa,
79	    sa->sa_family));
80
81	if (sa->sa_family == AF_INET) {
82		const struct sockaddr_in *sin = (const void *)sa;
83
84		key = &sin->sin_addr;
85		len = sizeof(sin->sin_addr);
86	} else {
87		const struct sockaddr_in6 *sin6 = (const void *)sa;
88
89		key = &sin6->sin6_addr;
90		len = sizeof(sin6->sin6_addr);
91		start = half;
92	}
93
94	hash = fnv_32_buf(key, len, FNV1_32_INIT);
95	hash = fnv_32_buf(&ifindex, sizeof(ifindex), hash);
96	hash %= half;
97
98	return (hash + start);
99}
100
101static inline int
102l2_cmp(const struct sockaddr *sa, struct l2t_entry *e)
103{
104
105	KASSERT(sa->sa_family == AF_INET || sa->sa_family == AF_INET6,
106	    ("%s: sa %p has unexpected sa_family %d", __func__, sa,
107	    sa->sa_family));
108
109	if (sa->sa_family == AF_INET) {
110		const struct sockaddr_in *sin = (const void *)sa;
111
112		return (e->addr[0] != sin->sin_addr.s_addr);
113	} else {
114		const struct sockaddr_in6 *sin6 = (const void *)sa;
115
116		return (memcmp(&e->addr[0], &sin6->sin6_addr, sizeof(e->addr)));
117	}
118}
119
120static inline void
121l2_store(const struct sockaddr *sa, struct l2t_entry *e)
122{
123
124	KASSERT(sa->sa_family == AF_INET || sa->sa_family == AF_INET6,
125	    ("%s: sa %p has unexpected sa_family %d", __func__, sa,
126	    sa->sa_family));
127
128	if (sa->sa_family == AF_INET) {
129		const struct sockaddr_in *sin = (const void *)sa;
130
131		e->addr[0] = sin->sin_addr.s_addr;
132		e->ipv6 = 0;
133	} else {
134		const struct sockaddr_in6 *sin6 = (const void *)sa;
135
136		memcpy(&e->addr[0], &sin6->sin6_addr, sizeof(e->addr));
137		e->ipv6 = 1;
138	}
139}
140
141/*
142 * Add a WR to an L2T entry's queue of work requests awaiting resolution.
143 * Must be called with the entry's lock held.
144 */
145static inline void
146arpq_enqueue(struct l2t_entry *e, struct wrqe *wr)
147{
148	mtx_assert(&e->lock, MA_OWNED);
149
150	STAILQ_INSERT_TAIL(&e->wr_list, wr, link);
151}
152
153static inline void
154send_pending(struct adapter *sc, struct l2t_entry *e)
155{
156	struct wrqe *wr;
157
158	mtx_assert(&e->lock, MA_OWNED);
159
160	while ((wr = STAILQ_FIRST(&e->wr_list)) != NULL) {
161		STAILQ_REMOVE_HEAD(&e->wr_list, link);
162		t4_wrq_tx(sc, wr);
163	}
164}
165
166static void
167resolution_failed(struct adapter *sc, struct l2t_entry *e)
168{
169	struct tom_data *td = sc->tom_softc;
170
171	mtx_assert(&e->lock, MA_OWNED);
172
173	mtx_lock(&td->unsent_wr_lock);
174	STAILQ_CONCAT(&td->unsent_wr_list, &e->wr_list);
175	mtx_unlock(&td->unsent_wr_lock);
176
177	taskqueue_enqueue(taskqueue_thread, &td->reclaim_wr_resources);
178}
179
180static void
181update_entry(struct adapter *sc, struct l2t_entry *e, uint8_t *lladdr,
182    uint16_t vtag)
183{
184
185	mtx_assert(&e->lock, MA_OWNED);
186
187	/*
188	 * The entry may be in active use (e->refcount > 0) or not.  We update
189	 * it even when it's not as this simplifies the case where we decide to
190	 * reuse the entry later.
191	 */
192
193	if (lladdr == NULL &&
194	    (e->state == L2T_STATE_RESOLVING || e->state == L2T_STATE_FAILED)) {
195		/*
196		 * Never got a valid L2 address for this one.  Just mark it as
197		 * failed instead of removing it from the hash (for which we'd
198		 * need to wlock the table).
199		 */
200		e->state = L2T_STATE_FAILED;
201		resolution_failed(sc, e);
202		return;
203
204	} else if (lladdr == NULL) {
205
206		/* Valid or already-stale entry was deleted (or expired) */
207
208		KASSERT(e->state == L2T_STATE_VALID ||
209		    e->state == L2T_STATE_STALE,
210		    ("%s: lladdr NULL, state %d", __func__, e->state));
211
212		e->state = L2T_STATE_STALE;
213
214	} else {
215
216		if (e->state == L2T_STATE_RESOLVING ||
217		    e->state == L2T_STATE_FAILED ||
218		    memcmp(e->dmac, lladdr, ETHER_ADDR_LEN)) {
219
220			/* unresolved -> resolved; or dmac changed */
221
222			memcpy(e->dmac, lladdr, ETHER_ADDR_LEN);
223			e->vlan = vtag;
224			t4_write_l2e(e, 1);
225		}
226		e->state = L2T_STATE_VALID;
227	}
228}
229
230static int
231resolve_entry(struct adapter *sc, struct l2t_entry *e)
232{
233	struct tom_data *td = sc->tom_softc;
234	struct toedev *tod = &td->tod;
235	struct sockaddr_in sin = {0};
236	struct sockaddr_in6 sin6 = {0};
237	struct sockaddr *sa;
238	uint8_t dmac[ETHER_HDR_LEN];
239	uint16_t vtag;
240	int rc;
241
242	if (e->ipv6 == 0) {
243		sin.sin_family = AF_INET;
244		sin.sin_len = sizeof(struct sockaddr_in);
245		sin.sin_addr.s_addr = e->addr[0];
246		sa = (void *)&sin;
247	} else {
248		sin6.sin6_family = AF_INET6;
249		sin6.sin6_len = sizeof(struct sockaddr_in6);
250		memcpy(&sin6.sin6_addr, &e->addr[0], sizeof(e->addr));
251		sa = (void *)&sin6;
252	}
253
254	vtag = EVL_MAKETAG(VLAN_NONE, 0, 0);
255	rc = toe_l2_resolve(tod, e->ifp, sa, dmac, &vtag);
256	if (rc == EWOULDBLOCK)
257		return (rc);
258
259	mtx_lock(&e->lock);
260	update_entry(sc, e, rc == 0 ? dmac : NULL, vtag);
261	mtx_unlock(&e->lock);
262
263	return (rc);
264}
265
266int
267t4_l2t_send_slow(struct adapter *sc, struct wrqe *wr, struct l2t_entry *e)
268{
269
270again:
271	switch (e->state) {
272	case L2T_STATE_STALE:     /* entry is stale, kick off revalidation */
273
274		if (resolve_entry(sc, e) != EWOULDBLOCK)
275			goto again;	/* entry updated, re-examine state */
276
277		/* Fall through */
278
279	case L2T_STATE_VALID:     /* fast-path, send the packet on */
280
281		t4_wrq_tx(sc, wr);
282		return (0);
283
284	case L2T_STATE_RESOLVING:
285	case L2T_STATE_SYNC_WRITE:
286
287		mtx_lock(&e->lock);
288		if (e->state != L2T_STATE_SYNC_WRITE &&
289		    e->state != L2T_STATE_RESOLVING) {
290			/* state changed by the time we got here */
291			mtx_unlock(&e->lock);
292			goto again;
293		}
294		arpq_enqueue(e, wr);
295		mtx_unlock(&e->lock);
296
297		if (resolve_entry(sc, e) == EWOULDBLOCK)
298			break;
299
300		mtx_lock(&e->lock);
301		if (e->state == L2T_STATE_VALID && !STAILQ_EMPTY(&e->wr_list))
302			send_pending(sc, e);
303		if (e->state == L2T_STATE_FAILED)
304			resolution_failed(sc, e);
305		mtx_unlock(&e->lock);
306		break;
307
308	case L2T_STATE_FAILED:
309		return (EHOSTUNREACH);
310	}
311
312	return (0);
313}
314
315int
316do_l2t_write_rpl2(struct sge_iq *iq, const struct rss_header *rss,
317    struct mbuf *m)
318{
319	struct adapter *sc = iq->adapter;
320	const struct cpl_l2t_write_rpl *rpl = (const void *)(rss + 1);
321	unsigned int tid = GET_TID(rpl);
322	unsigned int idx = tid % L2T_SIZE;
323
324	if (__predict_false(rpl->status != CPL_ERR_NONE)) {
325		log(LOG_ERR,
326		    "Unexpected L2T_WRITE_RPL (%u) for entry at hw_idx %u\n",
327		    rpl->status, idx);
328		return (EINVAL);
329	}
330
331	if (tid & F_SYNC_WR) {
332		struct l2t_entry *e = &sc->l2t->l2tab[idx - sc->vres.l2t.start];
333
334		mtx_lock(&e->lock);
335		if (e->state != L2T_STATE_SWITCHING) {
336			send_pending(sc, e);
337			e->state = L2T_STATE_VALID;
338		}
339		mtx_unlock(&e->lock);
340	}
341
342	return (0);
343}
344
345/*
346 * The TOE wants an L2 table entry that it can use to reach the next hop over
347 * the specified port.  Produce such an entry - create one if needed.
348 *
349 * Note that the ifnet could be a pseudo-device like if_vlan, if_lagg, etc. on
350 * top of the real cxgbe interface.
351 */
352struct l2t_entry *
353t4_l2t_get(struct port_info *pi, struct ifnet *ifp, struct sockaddr *sa)
354{
355	struct l2t_entry *e;
356	struct adapter *sc = pi->adapter;
357	struct l2t_data *d = sc->l2t;
358	u_int hash, smt_idx = pi->port_id;
359	uint16_t vid, pcp, vtag;
360
361	KASSERT(sa->sa_family == AF_INET || sa->sa_family == AF_INET6,
362	    ("%s: sa %p has unexpected sa_family %d", __func__, sa,
363	    sa->sa_family));
364
365	vid = VLAN_NONE;
366	pcp = 0;
367	if (ifp->if_type == IFT_L2VLAN) {
368		VLAN_TAG(ifp, &vid);
369		VLAN_PCP(ifp, &pcp);
370	} else if (ifp->if_pcp != IFNET_PCP_NONE) {
371		vid = 0;
372		pcp = ifp->if_pcp;
373	}
374	vtag = EVL_MAKETAG(vid, pcp, 0);
375
376	hash = l2_hash(d, sa, ifp->if_index);
377	rw_wlock(&d->lock);
378	for (e = d->l2tab[hash].first; e; e = e->next) {
379		if (l2_cmp(sa, e) == 0 && e->ifp == ifp && e->vlan == vtag &&
380		    e->smt_idx == smt_idx) {
381			l2t_hold(d, e);
382			goto done;
383		}
384	}
385
386	/* Need to allocate a new entry */
387	e = t4_alloc_l2e(d);
388	if (e) {
389		mtx_lock(&e->lock);          /* avoid race with t4_l2t_free */
390		e->next = d->l2tab[hash].first;
391		d->l2tab[hash].first = e;
392
393		e->state = L2T_STATE_RESOLVING;
394		l2_store(sa, e);
395		e->ifp = ifp;
396		e->smt_idx = smt_idx;
397		e->hash = hash;
398		e->lport = pi->lport;
399		e->wrq = &sc->sge.ctrlq[pi->port_id];
400		e->iqid = sc->sge.ofld_rxq[pi->vi[0].first_ofld_rxq].iq.abs_id;
401		atomic_store_rel_int(&e->refcnt, 1);
402		e->vlan = vtag;
403		mtx_unlock(&e->lock);
404	}
405done:
406	rw_wunlock(&d->lock);
407	return e;
408}
409
410/*
411 * Called when the host's ARP layer makes a change to some entry that is loaded
412 * into the HW L2 table.
413 */
414void
415t4_l2_update(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
416    uint8_t *lladdr, uint16_t vtag)
417{
418	struct adapter *sc = tod->tod_softc;
419	struct l2t_entry *e;
420	struct l2t_data *d = sc->l2t;
421	u_int hash;
422
423	KASSERT(d != NULL, ("%s: no L2 table", __func__));
424
425	hash = l2_hash(d, sa, ifp->if_index);
426	rw_rlock(&d->lock);
427	for (e = d->l2tab[hash].first; e; e = e->next) {
428		if (l2_cmp(sa, e) == 0 && e->ifp == ifp) {
429			mtx_lock(&e->lock);
430			if (atomic_load_acq_int(&e->refcnt))
431				goto found;
432			e->state = L2T_STATE_STALE;
433			mtx_unlock(&e->lock);
434			break;
435		}
436	}
437	rw_runlock(&d->lock);
438
439	/*
440	 * This is of no interest to us.  We've never had an offloaded
441	 * connection to this destination, and we aren't attempting one right
442	 * now.
443	 */
444	return;
445
446found:
447	rw_runlock(&d->lock);
448
449	KASSERT(e->state != L2T_STATE_UNUSED,
450	    ("%s: unused entry in the hash.", __func__));
451
452	update_entry(sc, e, lladdr, vtag);
453	mtx_unlock(&e->lock);
454}
455#endif
456