xref: /freebsd/sys/dev/cxgbe/t4_smt.c (revision 02e9120893770924227138ba49df1edb3896112a)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 #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_smt.h"
48 
49 /*
50  * Module locking notes:  There is a RW lock protecting the SMAC table as a
51  * whole plus a spinlock per SMT 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 SMT 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 SMT entry is fully contained in the lifetime of the TOE.
65  */
66 
67 /*
68  * Allocate a free SMT entry.  Must be called with smt_data.lock held.
69  */
70 struct smt_entry *
71 t4_find_or_alloc_sme(struct smt_data *s, uint8_t *smac)
72 {
73 	struct smt_entry *end, *e;
74 	struct smt_entry *first_free = NULL;
75 
76 	rw_assert(&s->lock, RA_WLOCKED);
77 	for (e = &s->smtab[0], end = &s->smtab[s->smt_size]; e != end; ++e) {
78 		if (atomic_load_acq_int(&e->refcnt) == 0) {
79 			if (!first_free)
80 				first_free = e;
81 		} else {
82 			if (e->state == SMT_STATE_SWITCHING) {
83 				/*
84 				 * This entry is actually in use. See if we can
85 				 * re-use it?
86 				 */
87 				if (memcmp(e->smac, smac, ETHER_ADDR_LEN) == 0)
88 					goto found_reuse;
89 			}
90 		}
91 	}
92 	if (first_free) {
93 		e = first_free;
94 		goto found;
95 	}
96 	return NULL;
97 
98 found:
99 	e->state = SMT_STATE_UNUSED;
100 found_reuse:
101 	atomic_add_int(&e->refcnt, 1);
102 	return e;
103 }
104 
105 /*
106  * Write an SMT entry.  Must be called with the entry locked.
107  */
108 int
109 t4_write_sme(struct smt_entry *e)
110 {
111 	struct smt_data *s;
112 	struct sge_wrq *wrq;
113 	struct adapter *sc;
114 	struct wrq_cookie cookie;
115 	struct cpl_smt_write_req *req;
116 	struct cpl_t6_smt_write_req *t6req;
117 	u8 row;
118 
119 	mtx_assert(&e->lock, MA_OWNED);
120 
121 	MPASS(e->wrq != NULL);
122 	wrq = e->wrq;
123 	sc = wrq->adapter;
124 	MPASS(wrq->adapter != NULL);
125 	s = sc->smt;
126 
127 
128 	if (chip_id(sc) <= CHELSIO_T5) {
129 		/* Source MAC Table (SMT) contains 256 SMAC entries
130 		 * organized in 128 rows of 2 entries each.
131 		 */
132 		req = start_wrq_wr(wrq, howmany(sizeof(*req), 16), &cookie);
133 		if (req == NULL)
134 			return (ENOMEM);
135 		INIT_TP_WR(req, 0);
136 		/* Each row contains an SMAC pair.
137 		 * LSB selects the SMAC entry within a row
138 		 */
139 		row = (e->idx >> 1);
140 		if (e->idx & 1) {
141 			req->pfvf1 = 0x0;
142 			memcpy(req->src_mac1, e->smac, ETHER_ADDR_LEN);
143 			/* fill pfvf0/src_mac0 with entry
144 			 * at prev index from smt-tab.
145 			 */
146 			req->pfvf0 = 0x0;
147 			memcpy(req->src_mac0, s->smtab[e->idx - 1].smac,
148 					ETHER_ADDR_LEN);
149 		} else {
150 			req->pfvf0 = 0x0;
151 			memcpy(req->src_mac0, e->smac, ETHER_ADDR_LEN);
152 			/* fill pfvf1/src_mac1 with entry
153 			 * at next index from smt-tab
154 			 */
155 			req->pfvf1 = 0x0;
156 			memcpy(req->src_mac1, s->smtab[e->idx + 1].smac,
157 					ETHER_ADDR_LEN);
158 		}
159 	} else {
160 		/* Source MAC Table (SMT) contains 256 SMAC entries */
161 		t6req = start_wrq_wr(wrq, howmany(sizeof(*t6req), 16), &cookie);
162 		if (t6req == NULL)
163 			return (ENOMEM);
164 		INIT_TP_WR(t6req, 0);
165 		req = (struct cpl_smt_write_req *)t6req;
166 
167 		/* fill pfvf0/src_mac0 from smt-tab */
168 		req->pfvf0 = 0x0;
169 		memcpy(req->src_mac0, s->smtab[e->idx].smac, ETHER_ADDR_LEN);
170 		row = e->idx;
171 	}
172 	OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_SMT_WRITE_REQ, e->idx |
173 					V_TID_QID(e->iqid)));
174 	req->params = htonl(V_SMTW_NORPL(0) |
175 			V_SMTW_IDX(row) |
176 			V_SMTW_OVLAN_IDX(0));
177 
178 	commit_wrq_wr(wrq, req, &cookie);
179 
180 	return (0);
181 }
182 
183 /*
184  * Allocate an SMT entry for use by a switching rule.
185  */
186 struct smt_entry *
187 t4_smt_alloc_switching(struct smt_data *s, uint8_t *smac)
188 {
189 	struct smt_entry *e;
190 
191 	MPASS(s != NULL);
192 	rw_wlock(&s->lock);
193 	e = t4_find_or_alloc_sme(s, smac);
194 	rw_wunlock(&s->lock);
195 	return e;
196 }
197 
198 /*
199  * Sets/updates the contents of a switching SMT entry that has been allocated
200  * with an earlier call to @t4_smt_alloc_switching.
201  */
202 int
203 t4_smt_set_switching(struct adapter *sc, struct smt_entry *e, uint16_t pfvf,
204 								uint8_t *smac)
205 {
206 	int rc = 0;
207 
208 	if (atomic_load_acq_int(&e->refcnt) == 1) {
209 		/* Setup the entry for the first time */
210 		mtx_lock(&e->lock);
211 		e->wrq = &sc->sge.ctrlq[0];
212 		e->iqid = sc->sge.fwq.abs_id;
213 		e->pfvf =  pfvf;
214 		e->state = SMT_STATE_SWITCHING;
215 		memcpy(e->smac, smac, ETHER_ADDR_LEN);
216 		rc = t4_write_sme(e);
217 		mtx_unlock(&e->lock);
218 	}
219 
220 	return (rc);
221 }
222 
223 int
224 t4_init_smt(struct adapter *sc, int flags)
225 {
226 	int i, smt_size;
227 	struct smt_data *s;
228 
229 	smt_size = SMT_SIZE;
230 	s = malloc(sizeof(*s) + smt_size * sizeof (struct smt_entry), M_CXGBE,
231 	    M_ZERO | flags);
232 	if (!s)
233 		return (ENOMEM);
234 
235 	s->smt_size = smt_size;
236 	rw_init(&s->lock, "SMT");
237 
238 	for (i = 0; i < smt_size; i++) {
239 		struct smt_entry *e = &s->smtab[i];
240 
241 		e->idx = i;
242 		e->state = SMT_STATE_UNUSED;
243 		mtx_init(&e->lock, "SMT_E", NULL, MTX_DEF);
244 		atomic_store_rel_int(&e->refcnt, 0);
245 	}
246 
247 	sc->smt = s;
248 
249 	return (0);
250 }
251 
252 int
253 t4_free_smt(struct smt_data *s)
254 {
255 	int i;
256 
257 	for (i = 0; i < s->smt_size; i++)
258 		mtx_destroy(&s->smtab[i].lock);
259 	rw_destroy(&s->lock);
260 	free(s, M_CXGBE);
261 
262 	return (0);
263 }
264 
265 int
266 do_smt_write_rpl(struct sge_iq *iq, const struct rss_header *rss,
267 		struct mbuf *m)
268 {
269 	struct adapter *sc = iq->adapter;
270 	const struct cpl_smt_write_rpl *rpl = (const void *)(rss + 1);
271 	unsigned int tid = GET_TID(rpl);
272 	unsigned int smtidx = G_TID_TID(tid);
273 
274 	if (__predict_false(rpl->status != CPL_ERR_NONE)) {
275 		struct smt_entry *e = &sc->smt->smtab[smtidx];
276 		log(LOG_ERR,
277 		    "Unexpected SMT_WRITE_RPL (%u) for entry at hw_idx %u\n",
278 		    rpl->status, smtidx);
279 		mtx_lock(&e->lock);
280 		e->state = SMT_STATE_ERROR;
281 		mtx_unlock(&e->lock);
282 		return (EINVAL);
283 	}
284 
285 	return (0);
286 }
287 
288 static char
289 smt_state(const struct smt_entry *e)
290 {
291 	switch (e->state) {
292 	case SMT_STATE_SWITCHING: return 'X';
293 	case SMT_STATE_ERROR: return 'E';
294 	default: return 'U';
295 	}
296 }
297 
298 int
299 sysctl_smt(SYSCTL_HANDLER_ARGS)
300 {
301 	struct adapter *sc = arg1;
302 	struct smt_data *smt = sc->smt;
303 	struct smt_entry *e;
304 	struct sbuf *sb;
305 	int rc, i, header = 0;
306 
307 	if (smt == NULL)
308 		return (ENXIO);
309 
310 	rc = sysctl_wire_old_buffer(req, 0);
311 	if (rc != 0)
312 		return (rc);
313 
314 	sb = sbuf_new_for_sysctl(NULL, NULL, SMT_SIZE, req);
315 	if (sb == NULL)
316 		return (ENOMEM);
317 
318 	e = &smt->smtab[0];
319 	for (i = 0; i < smt->smt_size; i++, e++) {
320 		mtx_lock(&e->lock);
321 		if (e->state == SMT_STATE_UNUSED)
322 			goto skip;
323 
324 		if (header == 0) {
325 			sbuf_printf(sb, " Idx "
326 			    "Ethernet address  State Users");
327 			header = 1;
328 		}
329 		sbuf_printf(sb, "\n%4u %02x:%02x:%02x:%02x:%02x:%02x "
330 			   "%c   %5u",
331 			   e->idx, e->smac[0], e->smac[1], e->smac[2],
332 			   e->smac[3], e->smac[4], e->smac[5],
333 			   smt_state(e), atomic_load_acq_int(&e->refcnt));
334 skip:
335 		mtx_unlock(&e->lock);
336 	}
337 
338 	rc = sbuf_finish(sb);
339 	sbuf_delete(sb);
340 
341 	return (rc);
342 }
343