1 /* if_en.c 4.70 82/10/17 */ 2 3 #include "en.h" 4 5 /* 6 * Xerox prototype (3 Mb) Ethernet interface driver. 7 */ 8 9 #include "../h/param.h" 10 #include "../h/systm.h" 11 #include "../h/mbuf.h" 12 #include "../h/pte.h" 13 #include "../h/buf.h" 14 #include "../h/protosw.h" 15 #include "../h/socket.h" 16 #include "../h/vmmac.h" 17 #include <errno.h> 18 19 #include "../net/if.h" 20 #include "../net/netisr.h" 21 #include "../net/route.h" 22 #include "../netinet/in.h" 23 #include "../netinet/in_systm.h" 24 #include "../netinet/ip.h" 25 #include "../netinet/ip_var.h" 26 #include "../netpup/pup.h" 27 28 #include "../vax/cpu.h" 29 #include "../vax/mtpr.h" 30 #include "../vaxif/if_en.h" 31 #include "../vaxif/if_enreg.h" 32 #include "../vaxif/if_uba.h" 33 #include "../vaxuba/ubareg.h" 34 #include "../vaxuba/ubavar.h" 35 36 #define ENMTU (1024+512) 37 #define ENMRU (1024+512+16) /* 16 is enough to receive trailer */ 38 39 int enprobe(), enattach(), enrint(), enxint(), encollide(); 40 struct uba_device *eninfo[NEN]; 41 u_short enstd[] = { 0 }; 42 struct uba_driver endriver = 43 { enprobe, 0, enattach, 0, enstd, "en", eninfo }; 44 #define ENUNIT(x) minor(x) 45 46 int eninit(),enoutput(),enreset(); 47 48 /* 49 * Ethernet software status per interface. 50 * 51 * Each interface is referenced by a network interface structure, 52 * es_if, which the routing code uses to locate the interface. 53 * This structure contains the output queue for the interface, its address, ... 54 * We also have, for each interface, a UBA interface structure, which 55 * contains information about the UNIBUS resources held by the interface: 56 * map registers, buffered data paths, etc. Information is cached in this 57 * structure for use by the if_uba.c routines in running the interface 58 * efficiently. 59 */ 60 struct en_softc { 61 struct ifnet es_if; /* network-visible interface */ 62 struct ifuba es_ifuba; /* UNIBUS resources */ 63 short es_delay; /* current output delay */ 64 short es_mask; /* mask for current output delay */ 65 short es_lastx; /* host last transmitted to */ 66 short es_oactive; /* is output active? */ 67 short es_olen; /* length of last output */ 68 } en_softc[NEN]; 69 70 /* 71 * Do output DMA to determine interface presence and 72 * interrupt vector. DMA is too short to disturb other hosts. 73 */ 74 enprobe(reg) 75 caddr_t reg; 76 { 77 register int br, cvec; /* r11, r10 value-result */ 78 register struct endevice *addr = (struct endevice *)reg; 79 80 #ifdef lint 81 br = 0; cvec = br; br = cvec; 82 enrint(0); enxint(0); encollide(0); 83 #endif 84 addr->en_istat = 0; 85 addr->en_owc = -1; 86 addr->en_oba = 0; 87 addr->en_ostat = EN_IEN|EN_GO; 88 DELAY(100000); 89 addr->en_ostat = 0; 90 #ifdef ECHACK 91 br = 0x16; 92 #endif 93 return (1); 94 } 95 96 /* 97 * Interface exists: make available by filling in network interface 98 * record. System will initialize the interface when it is ready 99 * to accept packets. 100 */ 101 enattach(ui) 102 struct uba_device *ui; 103 { 104 register struct en_softc *es = &en_softc[ui->ui_unit]; 105 register struct sockaddr_in *sin; 106 107 es->es_if.if_unit = ui->ui_unit; 108 es->es_if.if_name = "en"; 109 es->es_if.if_mtu = ENMTU; 110 es->es_if.if_net = ui->ui_flags; 111 es->es_if.if_host[0] = 112 (~(((struct endevice *)eninfo[ui->ui_unit]->ui_addr)->en_addr)) & 0xff; 113 sin = (struct sockaddr_in *)&es->es_if.if_addr; 114 sin->sin_family = AF_INET; 115 sin->sin_addr = if_makeaddr(es->es_if.if_net, es->es_if.if_host[0]); 116 sin = (struct sockaddr_in *)&es->es_if.if_broadaddr; 117 sin->sin_family = AF_INET; 118 sin->sin_addr = if_makeaddr(es->es_if.if_net, 0); 119 es->es_if.if_flags = IFF_BROADCAST; 120 es->es_if.if_init = eninit; 121 es->es_if.if_output = enoutput; 122 es->es_if.if_ubareset = enreset; 123 es->es_ifuba.ifu_flags = UBA_NEEDBDP | UBA_NEED16 | UBA_CANTWAIT; 124 if_attach(&es->es_if); 125 } 126 127 /* 128 * Reset of interface after UNIBUS reset. 129 * If interface is on specified uba, reset its state. 130 */ 131 enreset(unit, uban) 132 int unit, uban; 133 { 134 register struct uba_device *ui; 135 136 if (unit >= NEN || (ui = eninfo[unit]) == 0 || ui->ui_alive == 0 || 137 ui->ui_ubanum != uban) 138 return; 139 printf(" en%d", unit); 140 eninit(unit); 141 } 142 143 /* 144 * Initialization of interface; clear recorded pending 145 * operations, and reinitialize UNIBUS usage. 146 */ 147 eninit(unit) 148 int unit; 149 { 150 register struct en_softc *es = &en_softc[unit]; 151 register struct uba_device *ui = eninfo[unit]; 152 register struct endevice *addr; 153 int s; 154 155 if (if_ubainit(&es->es_ifuba, ui->ui_ubanum, 156 sizeof (struct en_header), (int)btoc(ENMRU)) == 0) { 157 printf("en%d: can't initialize\n", unit); 158 es->es_if.if_flags &= ~IFF_UP; 159 return; 160 } 161 addr = (struct endevice *)ui->ui_addr; 162 addr->en_istat = addr->en_ostat = 0; 163 164 /* 165 * Hang a receive and start any 166 * pending writes by faking a transmit complete. 167 */ 168 s = splimp(); 169 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 170 addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1; 171 addr->en_istat = EN_IEN|EN_GO; 172 es->es_oactive = 1; 173 es->es_if.if_flags |= IFF_UP; 174 enxint(unit); 175 splx(s); 176 if_rtinit(&es->es_if, RTF_UP); 177 } 178 179 int enalldelay = 0; 180 int enlastdel = 50; 181 int enlastmask = (~0) << 5; 182 183 /* 184 * Start or restart output on interface. 185 * If interface is already active, then this is a retransmit 186 * after a collision, and just restuff registers and delay. 187 * If interface is not already active, get another datagram 188 * to send off of the interface queue, and map it to the interface 189 * before starting the output. 190 */ 191 enstart(dev) 192 dev_t dev; 193 { 194 int unit = ENUNIT(dev); 195 struct uba_device *ui = eninfo[unit]; 196 register struct en_softc *es = &en_softc[unit]; 197 register struct endevice *addr; 198 struct mbuf *m; 199 int dest; 200 201 if (es->es_oactive) 202 goto restart; 203 204 /* 205 * Not already active: dequeue another request 206 * and map it to the UNIBUS. If no more requests, 207 * just return. 208 */ 209 IF_DEQUEUE(&es->es_if.if_snd, m); 210 if (m == 0) { 211 es->es_oactive = 0; 212 return; 213 } 214 dest = mtod(m, struct en_header *)->en_dhost; 215 es->es_olen = if_wubaput(&es->es_ifuba, m); 216 217 /* 218 * Ethernet cannot take back-to-back packets (no 219 * buffering in interface. To help avoid overrunning 220 * receivers, enforce a small delay (about 1ms) in interface: 221 * * between all packets when enalldelay 222 * * whenever last packet was broadcast 223 * * whenever this packet is to same host as last packet 224 */ 225 if (enalldelay || es->es_lastx == 0 || es->es_lastx == dest) { 226 es->es_delay = enlastdel; 227 es->es_mask = enlastmask; 228 } 229 es->es_lastx = dest; 230 231 restart: 232 /* 233 * Have request mapped to UNIBUS for transmission. 234 * Purge any stale data from this BDP, and start the otput. 235 */ 236 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 237 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_w.ifrw_bdp); 238 addr = (struct endevice *)ui->ui_addr; 239 addr->en_oba = (int)es->es_ifuba.ifu_w.ifrw_info; 240 addr->en_odelay = es->es_delay; 241 addr->en_owc = -((es->es_olen + 1) >> 1); 242 addr->en_ostat = EN_IEN|EN_GO; 243 es->es_oactive = 1; 244 } 245 246 /* 247 * Ethernet interface transmitter interrupt. 248 * Start another output if more data to send. 249 */ 250 enxint(unit) 251 int unit; 252 { 253 register struct uba_device *ui = eninfo[unit]; 254 register struct en_softc *es = &en_softc[unit]; 255 register struct endevice *addr = (struct endevice *)ui->ui_addr; 256 257 if (es->es_oactive == 0) 258 return; 259 if (es->es_mask && (addr->en_ostat&EN_OERROR)) { 260 es->es_if.if_oerrors++; 261 endocoll(unit); 262 return; 263 } 264 es->es_if.if_opackets++; 265 es->es_oactive = 0; 266 es->es_delay = 0; 267 es->es_mask = ~0; 268 if (es->es_ifuba.ifu_xtofree) { 269 m_freem(es->es_ifuba.ifu_xtofree); 270 es->es_ifuba.ifu_xtofree = 0; 271 } 272 if (es->es_if.if_snd.ifq_head == 0) { 273 es->es_lastx = 256; /* putatively illegal */ 274 return; 275 } 276 enstart(unit); 277 } 278 279 /* 280 * Collision on ethernet interface. Do exponential 281 * backoff, and retransmit. If have backed off all 282 * the way print warning diagnostic, and drop packet. 283 */ 284 encollide(unit) 285 int unit; 286 { 287 struct en_softc *es = &en_softc[unit]; 288 289 es->es_if.if_collisions++; 290 if (es->es_oactive == 0) 291 return; 292 endocoll(unit); 293 } 294 295 endocoll(unit) 296 int unit; 297 { 298 register struct en_softc *es = &en_softc[unit]; 299 300 /* 301 * Es_mask is a 16 bit number with n low zero bits, with 302 * n the number of backoffs. When es_mask is 0 we have 303 * backed off 16 times, and give up. 304 */ 305 if (es->es_mask == 0) { 306 printf("en%d: send error\n", unit); 307 enxint(unit); 308 return; 309 } 310 /* 311 * Another backoff. Restart with delay based on n low bits 312 * of the interval timer. 313 */ 314 es->es_mask <<= 1; 315 es->es_delay = mfpr(ICR) &~ es->es_mask; 316 enstart(unit); 317 } 318 319 struct sockaddr_pup pupsrc = { AF_PUP }; 320 struct sockaddr_pup pupdst = { AF_PUP }; 321 struct sockproto pupproto = { PF_PUP }; 322 /* 323 * Ethernet interface receiver interrupt. 324 * If input error just drop packet. 325 * Otherwise purge input buffered data path and examine 326 * packet to determine type. If can't determine length 327 * from type, then have to drop packet. Othewise decapsulate 328 * packet based on type and pass to type specific higher-level 329 * input routine. 330 */ 331 enrint(unit) 332 int unit; 333 { 334 register struct en_softc *es = &en_softc[unit]; 335 struct endevice *addr = (struct endevice *)eninfo[unit]->ui_addr; 336 register struct en_header *en; 337 struct mbuf *m; 338 int len; short resid; 339 register struct ifqueue *inq; 340 int off; 341 342 es->es_if.if_ipackets++; 343 344 /* 345 * Purge BDP; drop if input error indicated. 346 */ 347 if (es->es_ifuba.ifu_flags & UBA_NEEDBDP) 348 UBAPURGE(es->es_ifuba.ifu_uba, es->es_ifuba.ifu_r.ifrw_bdp); 349 if (addr->en_istat&EN_IERROR) { 350 es->es_if.if_ierrors++; 351 goto setup; 352 } 353 354 /* 355 * Calculate input data length. 356 * Get pointer to ethernet header (in input buffer). 357 * Deal with trailer protocol: if type is PUP trailer 358 * get true type from first 16-bit word past data. 359 * Remember that type was trailer by setting off. 360 */ 361 resid = addr->en_iwc; 362 if (resid) 363 resid |= 0176000; 364 len = (((sizeof (struct en_header) + ENMRU) >> 1) + resid) << 1; 365 len -= sizeof (struct en_header); 366 if (len > ENMRU) 367 goto setup; /* sanity */ 368 en = (struct en_header *)(es->es_ifuba.ifu_r.ifrw_addr); 369 #define endataaddr(en, off, type) ((type)(((caddr_t)((en)+1)+(off)))) 370 if (en->en_type >= ENPUP_TRAIL && 371 en->en_type < ENPUP_TRAIL+ENPUP_NTRAILER) { 372 off = (en->en_type - ENPUP_TRAIL) * 512; 373 if (off > ENMTU) 374 goto setup; /* sanity */ 375 en->en_type = *endataaddr(en, off, u_short *); 376 resid = *(endataaddr(en, off+2, u_short *)); 377 if (off + resid > len) 378 goto setup; /* sanity */ 379 len = off + resid; 380 } else 381 off = 0; 382 if (len == 0) 383 goto setup; 384 /* 385 * Pull packet off interface. Off is nonzero if packet 386 * has trailing header; if_rubaget will then force this header 387 * information to be at the front, but we still have to drop 388 * the type and length which are at the front of any trailer data. 389 */ 390 m = if_rubaget(&es->es_ifuba, len, off); 391 if (m == 0) 392 goto setup; 393 if (off) { 394 m->m_off += 2 * sizeof (u_short); 395 m->m_len -= 2 * sizeof (u_short); 396 } 397 switch (en->en_type) { 398 399 #ifdef INET 400 case ENPUP_IPTYPE: 401 schednetisr(NETISR_IP); 402 inq = &ipintrq; 403 break; 404 #endif 405 #ifdef PUP 406 case ENPUP_PUPTYPE: { 407 struct pup_header *pup = mtod(m, struct pup_header *); 408 409 pupproto.sp_protocol = pup->pup_type; 410 pupdst.spup_addr = pup->pup_dport; 411 pupsrc.spup_addr = pup->pup_sport; 412 raw_input(m, &pupproto, (struct sockaddr *)&pupsrc, 413 (struct sockaddr *)&pupdst); 414 goto setup; 415 } 416 #endif 417 default: 418 m_freem(m); 419 goto setup; 420 } 421 422 if (IF_QFULL(inq)) { 423 IF_DROP(inq); 424 m_freem(m); 425 } else 426 IF_ENQUEUE(inq, m); 427 428 setup: 429 /* 430 * Reset for next packet. 431 */ 432 addr->en_iba = es->es_ifuba.ifu_r.ifrw_info; 433 addr->en_iwc = -(sizeof (struct en_header) + ENMRU) >> 1; 434 addr->en_istat = EN_IEN|EN_GO; 435 } 436 437 /* 438 * Ethernet output routine. 439 * Encapsulate a packet of type family for the local net. 440 * Use trailer local net encapsulation if enough data in first 441 * packet leaves a multiple of 512 bytes of data in remainder. 442 */ 443 enoutput(ifp, m0, dst) 444 struct ifnet *ifp; 445 struct mbuf *m0; 446 struct sockaddr *dst; 447 { 448 int type, dest, s, error; 449 register struct mbuf *m = m0; 450 register struct en_header *en; 451 register int off; 452 453 switch (dst->sa_family) { 454 455 #ifdef INET 456 case AF_INET: 457 dest = ((struct sockaddr_in *)dst)->sin_addr.s_addr; 458 if (dest & 0x00ffff00) { 459 error = EPERM; /* ??? */ 460 goto bad; 461 } 462 dest = (dest >> 24) & 0xff; 463 off = ntohs((u_short)mtod(m, struct ip *)->ip_len) - m->m_len; 464 if (off > 0 && (off & 0x1ff) == 0 && 465 m->m_off >= MMINOFF + 2 * sizeof (u_short)) { 466 type = ENPUP_TRAIL + (off>>9); 467 m->m_off -= 2 * sizeof (u_short); 468 m->m_len += 2 * sizeof (u_short); 469 *mtod(m, u_short *) = ENPUP_IPTYPE; 470 *(mtod(m, u_short *) + 1) = m->m_len; 471 goto gottrailertype; 472 } 473 type = ENPUP_IPTYPE; 474 off = 0; 475 goto gottype; 476 #endif 477 #ifdef PUP 478 case AF_PUP: 479 dest = ((struct sockaddr_pup *)dst)->spup_addr.pp_host; 480 type = ENPUP_PUPTYPE; 481 off = 0; 482 goto gottype; 483 #endif 484 485 default: 486 printf("en%d: can't handle af%d\n", ifp->if_unit, 487 dst->sa_family); 488 error = EAFNOSUPPORT; 489 goto bad; 490 } 491 492 gottrailertype: 493 /* 494 * Packet to be sent as trailer: move first packet 495 * (control information) to end of chain. 496 */ 497 while (m->m_next) 498 m = m->m_next; 499 m->m_next = m0; 500 m = m0->m_next; 501 m0->m_next = 0; 502 m0 = m; 503 504 gottype: 505 /* 506 * Add local net header. If no space in first mbuf, 507 * allocate another. 508 */ 509 if (m->m_off > MMAXOFF || 510 MMINOFF + sizeof (struct en_header) > m->m_off) { 511 m = m_get(M_DONTWAIT); 512 if (m == 0) { 513 error = ENOBUFS; 514 goto bad; 515 } 516 m->m_next = m0; 517 m->m_off = MMINOFF; 518 m->m_len = sizeof (struct en_header); 519 } else { 520 m->m_off -= sizeof (struct en_header); 521 m->m_len += sizeof (struct en_header); 522 } 523 en = mtod(m, struct en_header *); 524 en->en_shost = ifp->if_host[0]; 525 en->en_dhost = dest; 526 en->en_type = type; 527 528 /* 529 * Queue message on interface, and start output if interface 530 * not yet active. 531 */ 532 s = splimp(); 533 if (IF_QFULL(&ifp->if_snd)) { 534 IF_DROP(&ifp->if_snd); 535 error = ENOBUFS; 536 goto qfull; 537 } 538 IF_ENQUEUE(&ifp->if_snd, m); 539 if (en_softc[ifp->if_unit].es_oactive == 0) 540 enstart(ifp->if_unit); 541 splx(s); 542 return (0); 543 qfull: 544 m0 = m; 545 splx(s); 546 bad: 547 m_freem(m0); 548 return (error); 549 } 550