xref: /freebsd/sys/dev/cxgbe/t4_smt.c (revision faf25f48d601ae39f5752602f3020e2e92605625)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2018 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 #include <sys/param.h>
35 #include <sys/eventhandler.h>
36 #include <sys/systm.h>
37 #include <sys/kernel.h>
38 #include <sys/module.h>
39 #include <sys/bus.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 #include <sys/rwlock.h>
43 #include <sys/socket.h>
44 #include <sys/sbuf.h>
45 #include <netinet/in.h>
46 
47 #include "common/common.h"
48 #include "common/t4_msg.h"
49 #include "t4_smt.h"
50 
51 /*
52  * Module locking notes:  There is a RW lock protecting the SMAC table as a
53  * whole plus a spinlock per SMT entry.  Entry lookups and allocations happen
54  * under the protection of the table lock, individual entry changes happen
55  * while holding that entry's spinlock.  The table lock nests outside the
56  * entry locks.  Allocations of new entries take the table lock as writers so
57  * no other lookups can happen while allocating new entries.  Entry updates
58  * take the table lock as readers so multiple entries can be updated in
59  * parallel.  An SMT entry can be dropped by decrementing its reference count
60  * and therefore can happen in parallel with entry allocation but no entry
61  * can change state or increment its ref count during allocation as both of
62  * these perform lookups.
63  *
64  * Note: We do not take references to ifnets in this module because both
65  * the TOE and the sockets already hold references to the interfaces and the
66  * lifetime of an SMT entry is fully contained in the lifetime of the TOE.
67  */
68 
69 /*
70  * Allocate a free SMT entry.  Must be called with smt_data.lock held.
71  */
72 struct smt_entry *
73 t4_find_or_alloc_sme(struct smt_data *s, uint8_t *smac)
74 {
75 	struct smt_entry *end, *e;
76 	struct smt_entry *first_free = NULL;
77 
78 	rw_assert(&s->lock, RA_WLOCKED);
79 	for (e = &s->smtab[0], end = &s->smtab[s->smt_size]; e != end; ++e) {
80 		if (atomic_load_acq_int(&e->refcnt) == 0) {
81 			if (!first_free)
82 				first_free = e;
83 		} else {
84 			if (e->state == SMT_STATE_SWITCHING) {
85 				/*
86 				 * This entry is actually in use. See if we can
87 				 * re-use it?
88 				 */
89 				if (memcmp(e->smac, smac, ETHER_ADDR_LEN) == 0)
90 					goto found_reuse;
91 			}
92 		}
93 	}
94 	if (first_free) {
95 		e = first_free;
96 		goto found;
97 	}
98 	return NULL;
99 
100 found:
101 	e->state = SMT_STATE_UNUSED;
102 found_reuse:
103 	atomic_add_int(&e->refcnt, 1);
104 	return e;
105 }
106 
107 /*
108  * Write an SMT entry.  Must be called with the entry locked.
109  */
110 int
111 t4_write_sme(struct smt_entry *e)
112 {
113 	struct smt_data *s;
114 	struct sge_wrq *wrq;
115 	struct adapter *sc;
116 	struct wrq_cookie cookie;
117 	struct cpl_smt_write_req *req;
118 	struct cpl_t6_smt_write_req *t6req;
119 	u8 row;
120 
121 	mtx_assert(&e->lock, MA_OWNED);
122 
123 	MPASS(e->wrq != NULL);
124 	wrq = e->wrq;
125 	sc = wrq->adapter;
126 	MPASS(wrq->adapter != NULL);
127 	s = sc->smt;
128 
129 
130 	if (chip_id(sc) <= CHELSIO_T5) {
131 		/* Source MAC Table (SMT) contains 256 SMAC entries
132 		 * organized in 128 rows of 2 entries each.
133 		 */
134 		req = start_wrq_wr(wrq, howmany(sizeof(*req), 16), &cookie);
135 		if (req == NULL)
136 			return (ENOMEM);
137 		INIT_TP_WR(req, 0);
138 		/* Each row contains an SMAC pair.
139 		 * LSB selects the SMAC entry within a row
140 		 */
141 		row = (e->idx >> 1);
142 		if (e->idx & 1) {
143 			req->pfvf1 = 0x0;
144 			memcpy(req->src_mac1, e->smac, ETHER_ADDR_LEN);
145 			/* fill pfvf0/src_mac0 with entry
146 			 * at prev index from smt-tab.
147 			 */
148 			req->pfvf0 = 0x0;
149 			memcpy(req->src_mac0, s->smtab[e->idx - 1].smac,
150 					ETHER_ADDR_LEN);
151 		} else {
152 			req->pfvf0 = 0x0;
153 			memcpy(req->src_mac0, e->smac, ETHER_ADDR_LEN);
154 			/* fill pfvf1/src_mac1 with entry
155 			 * at next index from smt-tab
156 			 */
157 			req->pfvf1 = 0x0;
158 			memcpy(req->src_mac1, s->smtab[e->idx + 1].smac,
159 					ETHER_ADDR_LEN);
160 		}
161 	} else {
162 		/* Source MAC Table (SMT) contains 256 SMAC entries */
163 		t6req = start_wrq_wr(wrq, howmany(sizeof(*t6req), 16), &cookie);
164 		if (t6req == NULL)
165 			return (ENOMEM);
166 		INIT_TP_WR(t6req, 0);
167 		req = (struct cpl_smt_write_req *)t6req;
168 
169 		/* fill pfvf0/src_mac0 from smt-tab */
170 		req->pfvf0 = 0x0;
171 		memcpy(req->src_mac0, s->smtab[e->idx].smac, ETHER_ADDR_LEN);
172 		row = e->idx;
173 	}
174 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_SMT_WRITE_REQ, e->idx |
175 					V_TID_QID(e->iqid)));
176 	req->params = htonl(V_SMTW_NORPL(0) |
177 			V_SMTW_IDX(row) |
178 			V_SMTW_OVLAN_IDX(0));
179 
180 	commit_wrq_wr(wrq, req, &cookie);
181 
182 	return (0);
183 }
184 
185 /*
186  * Allocate an SMT entry for use by a switching rule.
187  */
188 struct smt_entry *
189 t4_smt_alloc_switching(struct smt_data *s, uint8_t *smac)
190 {
191 	struct smt_entry *e;
192 
193 	MPASS(s != NULL);
194 	rw_wlock(&s->lock);
195 	e = t4_find_or_alloc_sme(s, smac);
196 	rw_wunlock(&s->lock);
197 	return e;
198 }
199 
200 /*
201  * Sets/updates the contents of a switching SMT entry that has been allocated
202  * with an earlier call to @t4_smt_alloc_switching.
203  */
204 int
205 t4_smt_set_switching(struct adapter *sc, struct smt_entry *e, uint16_t pfvf,
206 								uint8_t *smac)
207 {
208 	int rc = 0;
209 
210 	if (atomic_load_acq_int(&e->refcnt) == 1) {
211 		/* Setup the entry for the first time */
212 		mtx_lock(&e->lock);
213 		e->wrq = &sc->sge.ctrlq[0];
214 		e->iqid = sc->sge.fwq.abs_id;
215 		e->pfvf =  pfvf;
216 		e->state = SMT_STATE_SWITCHING;
217 		memcpy(e->smac, smac, ETHER_ADDR_LEN);
218 		rc = t4_write_sme(e);
219 		mtx_unlock(&e->lock);
220 	}
221 
222 	return (rc);
223 }
224 
225 int
226 t4_init_smt(struct adapter *sc, int flags)
227 {
228 	int i, smt_size;
229 	struct smt_data *s;
230 
231 	smt_size = SMT_SIZE;
232 	s = malloc(sizeof(*s) + smt_size * sizeof (struct smt_entry), M_CXGBE,
233 	    M_ZERO | flags);
234 	if (!s)
235 		return (ENOMEM);
236 
237 	s->smt_size = smt_size;
238 	rw_init(&s->lock, "SMT");
239 
240 	for (i = 0; i < smt_size; i++) {
241 		struct smt_entry *e = &s->smtab[i];
242 
243 		e->idx = i;
244 		e->state = SMT_STATE_UNUSED;
245 		mtx_init(&e->lock, "SMT_E", NULL, MTX_DEF);
246 		atomic_store_rel_int(&e->refcnt, 0);
247 	}
248 
249 	sc->smt = s;
250 
251 	return (0);
252 }
253 
254 int
255 t4_free_smt(struct smt_data *s)
256 {
257 	int i;
258 
259 	for (i = 0; i < s->smt_size; i++)
260 		mtx_destroy(&s->smtab[i].lock);
261 	rw_destroy(&s->lock);
262 	free(s, M_CXGBE);
263 
264 	return (0);
265 }
266 
267 int
268 do_smt_write_rpl(struct sge_iq *iq, const struct rss_header *rss,
269 		struct mbuf *m)
270 {
271 	struct adapter *sc = iq->adapter;
272 	const struct cpl_smt_write_rpl *rpl = (const void *)(rss + 1);
273 	unsigned int tid = GET_TID(rpl);
274 	unsigned int smtidx = G_TID_TID(tid);
275 
276 	if (__predict_false(rpl->status != CPL_ERR_NONE)) {
277 		struct smt_entry *e = &sc->smt->smtab[smtidx];
278 		log(LOG_ERR,
279 		    "Unexpected SMT_WRITE_RPL (%u) for entry at hw_idx %u\n",
280 		    rpl->status, smtidx);
281 		mtx_lock(&e->lock);
282 		e->state = SMT_STATE_ERROR;
283 		mtx_unlock(&e->lock);
284 		return (EINVAL);
285 	}
286 
287 	return (0);
288 }
289 
290 static char
291 smt_state(const struct smt_entry *e)
292 {
293 	switch (e->state) {
294 	case SMT_STATE_SWITCHING: return 'X';
295 	case SMT_STATE_ERROR: return 'E';
296 	default: return 'U';
297 	}
298 }
299 
300 int
301 sysctl_smt(SYSCTL_HANDLER_ARGS)
302 {
303 	struct adapter *sc = arg1;
304 	struct smt_data *smt = sc->smt;
305 	struct smt_entry *e;
306 	struct sbuf *sb;
307 	int rc, i, header = 0;
308 
309 	if (smt == NULL)
310 		return (ENXIO);
311 
312 	rc = sysctl_wire_old_buffer(req, 0);
313 	if (rc != 0)
314 		return (rc);
315 
316 	sb = sbuf_new_for_sysctl(NULL, NULL, SMT_SIZE, req);
317 	if (sb == NULL)
318 		return (ENOMEM);
319 
320 	e = &smt->smtab[0];
321 	for (i = 0; i < smt->smt_size; i++, e++) {
322 		mtx_lock(&e->lock);
323 		if (e->state == SMT_STATE_UNUSED)
324 			goto skip;
325 
326 		if (header == 0) {
327 			sbuf_printf(sb, " Idx "
328 			    "Ethernet address  State Users");
329 			header = 1;
330 		}
331 		sbuf_printf(sb, "\n%4u %02x:%02x:%02x:%02x:%02x:%02x "
332 			   "%c   %5u",
333 			   e->idx, e->smac[0], e->smac[1], e->smac[2],
334 			   e->smac[3], e->smac[4], e->smac[5],
335 			   smt_state(e), atomic_load_acq_int(&e->refcnt));
336 skip:
337 		mtx_unlock(&e->lock);
338 	}
339 
340 	rc = sbuf_finish(sb);
341 	sbuf_delete(sb);
342 
343 	return (rc);
344 }
345