1 /*- 2 * Copyright (c) 2012 Chelsio Communications, Inc. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 #include <sys/cdefs.h> 27 __FBSDID("$FreeBSD$"); 28 29 #include "opt_inet.h" 30 #include "opt_inet6.h" 31 32 #include <sys/param.h> 33 #include <sys/systm.h> 34 #include <sys/kernel.h> 35 #include <sys/module.h> 36 #include <sys/bus.h> 37 #include <sys/lock.h> 38 #include <sys/mutex.h> 39 #include <sys/rwlock.h> 40 #include <sys/socket.h> 41 #include <sys/sbuf.h> 42 #include <netinet/in.h> 43 44 #include "common/common.h" 45 #include "common/jhash.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 refereces 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[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 /* 110 * Write an L2T entry. Must be called with the entry locked. 111 * The write may be synchronous or asynchronous. 112 */ 113 int 114 t4_write_l2e(struct adapter *sc, struct l2t_entry *e, int sync) 115 { 116 struct wrqe *wr; 117 struct cpl_l2t_write_req *req; 118 119 mtx_assert(&e->lock, MA_OWNED); 120 121 wr = alloc_wrqe(sizeof(*req), &sc->sge.mgmtq); 122 if (wr == NULL) 123 return (ENOMEM); 124 req = wrtod(wr); 125 126 INIT_TP_WR(req, 0); 127 OPCODE_TID(req) = htonl(MK_OPCODE_TID(CPL_L2T_WRITE_REQ, e->idx | 128 V_SYNC_WR(sync) | V_TID_QID(sc->sge.fwq.abs_id))); 129 req->params = htons(V_L2T_W_PORT(e->lport) | V_L2T_W_NOREPLY(!sync)); 130 req->l2t_idx = htons(e->idx); 131 req->vlan = htons(e->vlan); 132 memcpy(req->dst_mac, e->dmac, sizeof(req->dst_mac)); 133 134 t4_wrq_tx(sc, wr); 135 136 if (sync && e->state != L2T_STATE_SWITCHING) 137 e->state = L2T_STATE_SYNC_WRITE; 138 139 return (0); 140 } 141 142 /* 143 * Allocate an L2T entry for use by a switching rule. Such need to be 144 * explicitly freed and while busy they are not on any hash chain, so normal 145 * address resolution updates do not see them. 146 */ 147 struct l2t_entry * 148 t4_l2t_alloc_switching(struct l2t_data *d) 149 { 150 struct l2t_entry *e; 151 152 rw_wlock(&d->lock); 153 e = t4_alloc_l2e(d); 154 if (e) { 155 mtx_lock(&e->lock); /* avoid race with t4_l2t_free */ 156 e->state = L2T_STATE_SWITCHING; 157 atomic_store_rel_int(&e->refcnt, 1); 158 mtx_unlock(&e->lock); 159 } 160 rw_wunlock(&d->lock); 161 return e; 162 } 163 164 /* 165 * Sets/updates the contents of a switching L2T entry that has been allocated 166 * with an earlier call to @t4_l2t_alloc_switching. 167 */ 168 int 169 t4_l2t_set_switching(struct adapter *sc, struct l2t_entry *e, uint16_t vlan, 170 uint8_t port, uint8_t *eth_addr) 171 { 172 int rc; 173 174 e->vlan = vlan; 175 e->lport = port; 176 memcpy(e->dmac, eth_addr, ETHER_ADDR_LEN); 177 mtx_lock(&e->lock); 178 rc = t4_write_l2e(sc, e, 0); 179 mtx_unlock(&e->lock); 180 return (rc); 181 } 182 183 int 184 t4_init_l2t(struct adapter *sc, int flags) 185 { 186 int i; 187 struct l2t_data *d; 188 189 d = malloc(sizeof(*d), M_CXGBE, M_ZERO | flags); 190 if (!d) 191 return (ENOMEM); 192 193 d->rover = d->l2tab; 194 atomic_store_rel_int(&d->nfree, L2T_SIZE); 195 rw_init(&d->lock, "L2T"); 196 197 for (i = 0; i < L2T_SIZE; i++) { 198 struct l2t_entry *e = &d->l2tab[i]; 199 200 e->idx = i; 201 e->state = L2T_STATE_UNUSED; 202 mtx_init(&e->lock, "L2T_E", NULL, MTX_DEF); 203 STAILQ_INIT(&e->wr_list); 204 atomic_store_rel_int(&e->refcnt, 0); 205 } 206 207 sc->l2t = d; 208 t4_register_cpl_handler(sc, CPL_L2T_WRITE_RPL, do_l2t_write_rpl); 209 210 return (0); 211 } 212 213 int 214 t4_free_l2t(struct l2t_data *d) 215 { 216 int i; 217 218 for (i = 0; i < L2T_SIZE; i++) 219 mtx_destroy(&d->l2tab[i].lock); 220 rw_destroy(&d->lock); 221 free(d, M_CXGBE); 222 223 return (0); 224 } 225 226 int 227 do_l2t_write_rpl(struct sge_iq *iq, const struct rss_header *rss, 228 struct mbuf *m) 229 { 230 const struct cpl_l2t_write_rpl *rpl = (const void *)(rss + 1); 231 unsigned int tid = GET_TID(rpl); 232 unsigned int idx = tid & (L2T_SIZE - 1); 233 234 if (__predict_false(rpl->status != CPL_ERR_NONE)) { 235 log(LOG_ERR, 236 "Unexpected L2T_WRITE_RPL status %u for entry %u\n", 237 rpl->status, idx); 238 return (EINVAL); 239 } 240 241 return (0); 242 } 243 244 #ifdef SBUF_DRAIN 245 static inline unsigned int 246 vlan_prio(const struct l2t_entry *e) 247 { 248 return e->vlan >> 13; 249 } 250 251 static char 252 l2e_state(const struct l2t_entry *e) 253 { 254 switch (e->state) { 255 case L2T_STATE_VALID: return 'V'; /* valid, fast-path entry */ 256 case L2T_STATE_STALE: return 'S'; /* needs revalidation, but usable */ 257 case L2T_STATE_SYNC_WRITE: return 'W'; 258 case L2T_STATE_RESOLVING: return STAILQ_EMPTY(&e->wr_list) ? 'R' : 'A'; 259 case L2T_STATE_SWITCHING: return 'X'; 260 default: return 'U'; 261 } 262 } 263 264 int 265 sysctl_l2t(SYSCTL_HANDLER_ARGS) 266 { 267 struct adapter *sc = arg1; 268 struct l2t_data *l2t = sc->l2t; 269 struct l2t_entry *e; 270 struct sbuf *sb; 271 int rc, i, header = 0; 272 char ip[60]; 273 274 if (l2t == NULL) 275 return (ENXIO); 276 277 rc = sysctl_wire_old_buffer(req, 0); 278 if (rc != 0) 279 return (rc); 280 281 sb = sbuf_new_for_sysctl(NULL, NULL, 4096, req); 282 if (sb == NULL) 283 return (ENOMEM); 284 285 e = &l2t->l2tab[0]; 286 for (i = 0; i < L2T_SIZE; i++, e++) { 287 mtx_lock(&e->lock); 288 if (e->state == L2T_STATE_UNUSED) 289 goto skip; 290 291 if (header == 0) { 292 sbuf_printf(sb, " Idx IP address " 293 "Ethernet address VLAN/P LP State Users Port"); 294 header = 1; 295 } 296 if (e->state == L2T_STATE_SWITCHING) 297 ip[0] = 0; 298 else 299 snprintf(ip, sizeof(ip), "%s", 300 inet_ntoa(*(struct in_addr *)&e->addr)); 301 302 /* XXX: e->ifp may not be around */ 303 sbuf_printf(sb, "\n%4u %-15s %02x:%02x:%02x:%02x:%02x:%02x %4d" 304 " %u %2u %c %5u %s", 305 e->idx, ip, e->dmac[0], e->dmac[1], e->dmac[2], 306 e->dmac[3], e->dmac[4], e->dmac[5], 307 e->vlan & 0xfff, vlan_prio(e), e->lport, 308 l2e_state(e), atomic_load_acq_int(&e->refcnt), 309 e->ifp->if_xname); 310 skip: 311 mtx_unlock(&e->lock); 312 } 313 314 rc = sbuf_finish(sb); 315 sbuf_delete(sb); 316 317 return (rc); 318 } 319 #endif 320