xref: /linux/arch/sparc/kernel/viohs.c (revision f884ab15afdc5514e88105c92a4e2e1e6539869a)
1 /* viohs.c: LDOM Virtual I/O handshake helper layer.
2  *
3  * Copyright (C) 2007 David S. Miller <davem@davemloft.net>
4  */
5 
6 #include <linux/kernel.h>
7 #include <linux/export.h>
8 #include <linux/string.h>
9 #include <linux/delay.h>
10 #include <linux/sched.h>
11 #include <linux/slab.h>
12 
13 #include <asm/ldc.h>
14 #include <asm/vio.h>
15 
16 int vio_ldc_send(struct vio_driver_state *vio, void *data, int len)
17 {
18 	int err, limit = 1000;
19 
20 	err = -EINVAL;
21 	while (limit-- > 0) {
22 		err = ldc_write(vio->lp, data, len);
23 		if (!err || (err != -EAGAIN))
24 			break;
25 		udelay(1);
26 	}
27 
28 	return err;
29 }
30 EXPORT_SYMBOL(vio_ldc_send);
31 
32 static int send_ctrl(struct vio_driver_state *vio,
33 		     struct vio_msg_tag *tag, int len)
34 {
35 	tag->sid = vio_send_sid(vio);
36 	return vio_ldc_send(vio, tag, len);
37 }
38 
39 static void init_tag(struct vio_msg_tag *tag, u8 type, u8 stype, u16 stype_env)
40 {
41 	tag->type = type;
42 	tag->stype = stype;
43 	tag->stype_env = stype_env;
44 }
45 
46 static int send_version(struct vio_driver_state *vio, u16 major, u16 minor)
47 {
48 	struct vio_ver_info pkt;
49 
50 	vio->_local_sid = (u32) sched_clock();
51 
52 	memset(&pkt, 0, sizeof(pkt));
53 	init_tag(&pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_VER_INFO);
54 	pkt.major = major;
55 	pkt.minor = minor;
56 	pkt.dev_class = vio->dev_class;
57 
58 	viodbg(HS, "SEND VERSION INFO maj[%u] min[%u] devclass[%u]\n",
59 	       major, minor, vio->dev_class);
60 
61 	return send_ctrl(vio, &pkt.tag, sizeof(pkt));
62 }
63 
64 static int start_handshake(struct vio_driver_state *vio)
65 {
66 	int err;
67 
68 	viodbg(HS, "START HANDSHAKE\n");
69 
70 	vio->hs_state = VIO_HS_INVALID;
71 
72 	err = send_version(vio,
73 			   vio->ver_table[0].major,
74 			   vio->ver_table[0].minor);
75 	if (err < 0)
76 		return err;
77 
78 	return 0;
79 }
80 
81 static void flush_rx_dring(struct vio_driver_state *vio)
82 {
83 	struct vio_dring_state *dr;
84 	u64 ident;
85 
86 	BUG_ON(!(vio->dr_state & VIO_DR_STATE_RXREG));
87 
88 	dr = &vio->drings[VIO_DRIVER_RX_RING];
89 	ident = dr->ident;
90 
91 	BUG_ON(!vio->desc_buf);
92 	kfree(vio->desc_buf);
93 	vio->desc_buf = NULL;
94 
95 	memset(dr, 0, sizeof(*dr));
96 	dr->ident = ident;
97 }
98 
99 void vio_link_state_change(struct vio_driver_state *vio, int event)
100 {
101 	if (event == LDC_EVENT_UP) {
102 		vio->hs_state = VIO_HS_INVALID;
103 
104 		switch (vio->dev_class) {
105 		case VDEV_NETWORK:
106 		case VDEV_NETWORK_SWITCH:
107 			vio->dr_state = (VIO_DR_STATE_TXREQ |
108 					 VIO_DR_STATE_RXREQ);
109 			break;
110 
111 		case VDEV_DISK:
112 			vio->dr_state = VIO_DR_STATE_TXREQ;
113 			break;
114 		case VDEV_DISK_SERVER:
115 			vio->dr_state = VIO_DR_STATE_RXREQ;
116 			break;
117 		}
118 		start_handshake(vio);
119 	} else if (event == LDC_EVENT_RESET) {
120 		vio->hs_state = VIO_HS_INVALID;
121 
122 		if (vio->dr_state & VIO_DR_STATE_RXREG)
123 			flush_rx_dring(vio);
124 
125 		vio->dr_state = 0x00;
126 		memset(&vio->ver, 0, sizeof(vio->ver));
127 
128 		ldc_disconnect(vio->lp);
129 	}
130 }
131 EXPORT_SYMBOL(vio_link_state_change);
132 
133 static int handshake_failure(struct vio_driver_state *vio)
134 {
135 	struct vio_dring_state *dr;
136 
137 	/* XXX Put policy here...  Perhaps start a timer to fire
138 	 * XXX in 100 ms, which will bring the link up and retry
139 	 * XXX the handshake.
140 	 */
141 
142 	viodbg(HS, "HANDSHAKE FAILURE\n");
143 
144 	vio->dr_state &= ~(VIO_DR_STATE_TXREG |
145 			   VIO_DR_STATE_RXREG);
146 
147 	dr = &vio->drings[VIO_DRIVER_RX_RING];
148 	memset(dr, 0, sizeof(*dr));
149 
150 	kfree(vio->desc_buf);
151 	vio->desc_buf = NULL;
152 	vio->desc_buf_len = 0;
153 
154 	vio->hs_state = VIO_HS_INVALID;
155 
156 	return -ECONNRESET;
157 }
158 
159 static int process_unknown(struct vio_driver_state *vio, void *arg)
160 {
161 	struct vio_msg_tag *pkt = arg;
162 
163 	viodbg(HS, "UNKNOWN CONTROL [%02x:%02x:%04x:%08x]\n",
164 	       pkt->type, pkt->stype, pkt->stype_env, pkt->sid);
165 
166 	printk(KERN_ERR "vio: ID[%lu] Resetting connection.\n",
167 	       vio->vdev->channel_id);
168 
169 	ldc_disconnect(vio->lp);
170 
171 	return -ECONNRESET;
172 }
173 
174 static int send_dreg(struct vio_driver_state *vio)
175 {
176 	struct vio_dring_state *dr = &vio->drings[VIO_DRIVER_TX_RING];
177 	union {
178 		struct vio_dring_register pkt;
179 		char all[sizeof(struct vio_dring_register) +
180 			 (sizeof(struct ldc_trans_cookie) *
181 			  dr->ncookies)];
182 	} u;
183 	int i;
184 
185 	memset(&u, 0, sizeof(u));
186 	init_tag(&u.pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_DRING_REG);
187 	u.pkt.dring_ident = 0;
188 	u.pkt.num_descr = dr->num_entries;
189 	u.pkt.descr_size = dr->entry_size;
190 	u.pkt.options = VIO_TX_DRING;
191 	u.pkt.num_cookies = dr->ncookies;
192 
193 	viodbg(HS, "SEND DRING_REG INFO ndesc[%u] dsz[%u] opt[0x%x] "
194 	       "ncookies[%u]\n",
195 	       u.pkt.num_descr, u.pkt.descr_size, u.pkt.options,
196 	       u.pkt.num_cookies);
197 
198 	for (i = 0; i < dr->ncookies; i++) {
199 		u.pkt.cookies[i] = dr->cookies[i];
200 
201 		viodbg(HS, "DRING COOKIE(%d) [%016llx:%016llx]\n",
202 		       i,
203 		       (unsigned long long) u.pkt.cookies[i].cookie_addr,
204 		       (unsigned long long) u.pkt.cookies[i].cookie_size);
205 	}
206 
207 	return send_ctrl(vio, &u.pkt.tag, sizeof(u));
208 }
209 
210 static int send_rdx(struct vio_driver_state *vio)
211 {
212 	struct vio_rdx pkt;
213 
214 	memset(&pkt, 0, sizeof(pkt));
215 
216 	init_tag(&pkt.tag, VIO_TYPE_CTRL, VIO_SUBTYPE_INFO, VIO_RDX);
217 
218 	viodbg(HS, "SEND RDX INFO\n");
219 
220 	return send_ctrl(vio, &pkt.tag, sizeof(pkt));
221 }
222 
223 static int send_attr(struct vio_driver_state *vio)
224 {
225 	return vio->ops->send_attr(vio);
226 }
227 
228 static struct vio_version *find_by_major(struct vio_driver_state *vio,
229 					 u16 major)
230 {
231 	struct vio_version *ret = NULL;
232 	int i;
233 
234 	for (i = 0; i < vio->ver_table_entries; i++) {
235 		struct vio_version *v = &vio->ver_table[i];
236 		if (v->major <= major) {
237 			ret = v;
238 			break;
239 		}
240 	}
241 	return ret;
242 }
243 
244 static int process_ver_info(struct vio_driver_state *vio,
245 			    struct vio_ver_info *pkt)
246 {
247 	struct vio_version *vap;
248 	int err;
249 
250 	viodbg(HS, "GOT VERSION INFO maj[%u] min[%u] devclass[%u]\n",
251 	       pkt->major, pkt->minor, pkt->dev_class);
252 
253 	if (vio->hs_state != VIO_HS_INVALID) {
254 		/* XXX Perhaps invoke start_handshake? XXX */
255 		memset(&vio->ver, 0, sizeof(vio->ver));
256 		vio->hs_state = VIO_HS_INVALID;
257 	}
258 
259 	vap = find_by_major(vio, pkt->major);
260 
261 	vio->_peer_sid = pkt->tag.sid;
262 
263 	if (!vap) {
264 		pkt->tag.stype = VIO_SUBTYPE_NACK;
265 		pkt->major = 0;
266 		pkt->minor = 0;
267 		viodbg(HS, "SEND VERSION NACK maj[0] min[0]\n");
268 		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
269 	} else if (vap->major != pkt->major) {
270 		pkt->tag.stype = VIO_SUBTYPE_NACK;
271 		pkt->major = vap->major;
272 		pkt->minor = vap->minor;
273 		viodbg(HS, "SEND VERSION NACK maj[%u] min[%u]\n",
274 		       pkt->major, pkt->minor);
275 		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
276 	} else {
277 		struct vio_version ver = {
278 			.major = pkt->major,
279 			.minor = pkt->minor,
280 		};
281 		if (ver.minor > vap->minor)
282 			ver.minor = vap->minor;
283 		pkt->minor = ver.minor;
284 		pkt->tag.stype = VIO_SUBTYPE_ACK;
285 		viodbg(HS, "SEND VERSION ACK maj[%u] min[%u]\n",
286 		       pkt->major, pkt->minor);
287 		err = send_ctrl(vio, &pkt->tag, sizeof(*pkt));
288 		if (err > 0) {
289 			vio->ver = ver;
290 			vio->hs_state = VIO_HS_GOTVERS;
291 		}
292 	}
293 	if (err < 0)
294 		return handshake_failure(vio);
295 
296 	return 0;
297 }
298 
299 static int process_ver_ack(struct vio_driver_state *vio,
300 			   struct vio_ver_info *pkt)
301 {
302 	viodbg(HS, "GOT VERSION ACK maj[%u] min[%u] devclass[%u]\n",
303 	       pkt->major, pkt->minor, pkt->dev_class);
304 
305 	if (vio->hs_state & VIO_HS_GOTVERS) {
306 		if (vio->ver.major != pkt->major ||
307 		    vio->ver.minor != pkt->minor) {
308 			pkt->tag.stype = VIO_SUBTYPE_NACK;
309 			(void) send_ctrl(vio, &pkt->tag, sizeof(*pkt));
310 			return handshake_failure(vio);
311 		}
312 	} else {
313 		vio->ver.major = pkt->major;
314 		vio->ver.minor = pkt->minor;
315 		vio->hs_state = VIO_HS_GOTVERS;
316 	}
317 
318 	switch (vio->dev_class) {
319 	case VDEV_NETWORK:
320 	case VDEV_DISK:
321 		if (send_attr(vio) < 0)
322 			return handshake_failure(vio);
323 		break;
324 
325 	default:
326 		break;
327 	}
328 
329 	return 0;
330 }
331 
332 static int process_ver_nack(struct vio_driver_state *vio,
333 			    struct vio_ver_info *pkt)
334 {
335 	struct vio_version *nver;
336 
337 	viodbg(HS, "GOT VERSION NACK maj[%u] min[%u] devclass[%u]\n",
338 	       pkt->major, pkt->minor, pkt->dev_class);
339 
340 	if (pkt->major == 0 && pkt->minor == 0)
341 		return handshake_failure(vio);
342 	nver = find_by_major(vio, pkt->major);
343 	if (!nver)
344 		return handshake_failure(vio);
345 
346 	if (send_version(vio, nver->major, nver->minor) < 0)
347 		return handshake_failure(vio);
348 
349 	return 0;
350 }
351 
352 static int process_ver(struct vio_driver_state *vio, struct vio_ver_info *pkt)
353 {
354 	switch (pkt->tag.stype) {
355 	case VIO_SUBTYPE_INFO:
356 		return process_ver_info(vio, pkt);
357 
358 	case VIO_SUBTYPE_ACK:
359 		return process_ver_ack(vio, pkt);
360 
361 	case VIO_SUBTYPE_NACK:
362 		return process_ver_nack(vio, pkt);
363 
364 	default:
365 		return handshake_failure(vio);
366 	}
367 }
368 
369 static int process_attr(struct vio_driver_state *vio, void *pkt)
370 {
371 	int err;
372 
373 	if (!(vio->hs_state & VIO_HS_GOTVERS))
374 		return handshake_failure(vio);
375 
376 	err = vio->ops->handle_attr(vio, pkt);
377 	if (err < 0) {
378 		return handshake_failure(vio);
379 	} else {
380 		vio->hs_state |= VIO_HS_GOT_ATTR;
381 
382 		if ((vio->dr_state & VIO_DR_STATE_TXREQ) &&
383 		    !(vio->hs_state & VIO_HS_SENT_DREG)) {
384 			if (send_dreg(vio) < 0)
385 				return handshake_failure(vio);
386 
387 			vio->hs_state |= VIO_HS_SENT_DREG;
388 		}
389 	}
390 	return 0;
391 }
392 
393 static int all_drings_registered(struct vio_driver_state *vio)
394 {
395 	int need_rx, need_tx;
396 
397 	need_rx = (vio->dr_state & VIO_DR_STATE_RXREQ);
398 	need_tx = (vio->dr_state & VIO_DR_STATE_TXREQ);
399 
400 	if (need_rx &&
401 	    !(vio->dr_state & VIO_DR_STATE_RXREG))
402 		return 0;
403 
404 	if (need_tx &&
405 	    !(vio->dr_state & VIO_DR_STATE_TXREG))
406 		return 0;
407 
408 	return 1;
409 }
410 
411 static int process_dreg_info(struct vio_driver_state *vio,
412 			     struct vio_dring_register *pkt)
413 {
414 	struct vio_dring_state *dr;
415 	int i, len;
416 
417 	viodbg(HS, "GOT DRING_REG INFO ident[%llx] "
418 	       "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
419 	       (unsigned long long) pkt->dring_ident,
420 	       pkt->num_descr, pkt->descr_size, pkt->options,
421 	       pkt->num_cookies);
422 
423 	if (!(vio->dr_state & VIO_DR_STATE_RXREQ))
424 		goto send_nack;
425 
426 	if (vio->dr_state & VIO_DR_STATE_RXREG)
427 		goto send_nack;
428 
429 	BUG_ON(vio->desc_buf);
430 
431 	vio->desc_buf = kzalloc(pkt->descr_size, GFP_ATOMIC);
432 	if (!vio->desc_buf)
433 		goto send_nack;
434 
435 	vio->desc_buf_len = pkt->descr_size;
436 
437 	dr = &vio->drings[VIO_DRIVER_RX_RING];
438 
439 	dr->num_entries = pkt->num_descr;
440 	dr->entry_size = pkt->descr_size;
441 	dr->ncookies = pkt->num_cookies;
442 	for (i = 0; i < dr->ncookies; i++) {
443 		dr->cookies[i] = pkt->cookies[i];
444 
445 		viodbg(HS, "DRING COOKIE(%d) [%016llx:%016llx]\n",
446 		       i,
447 		       (unsigned long long)
448 		       pkt->cookies[i].cookie_addr,
449 		       (unsigned long long)
450 		       pkt->cookies[i].cookie_size);
451 	}
452 
453 	pkt->tag.stype = VIO_SUBTYPE_ACK;
454 	pkt->dring_ident = ++dr->ident;
455 
456 	viodbg(HS, "SEND DRING_REG ACK ident[%llx]\n",
457 	       (unsigned long long) pkt->dring_ident);
458 
459 	len = (sizeof(*pkt) +
460 	       (dr->ncookies * sizeof(struct ldc_trans_cookie)));
461 	if (send_ctrl(vio, &pkt->tag, len) < 0)
462 		goto send_nack;
463 
464 	vio->dr_state |= VIO_DR_STATE_RXREG;
465 
466 	return 0;
467 
468 send_nack:
469 	pkt->tag.stype = VIO_SUBTYPE_NACK;
470 	viodbg(HS, "SEND DRING_REG NACK\n");
471 	(void) send_ctrl(vio, &pkt->tag, sizeof(*pkt));
472 
473 	return handshake_failure(vio);
474 }
475 
476 static int process_dreg_ack(struct vio_driver_state *vio,
477 			    struct vio_dring_register *pkt)
478 {
479 	struct vio_dring_state *dr;
480 
481 	viodbg(HS, "GOT DRING_REG ACK ident[%llx] "
482 	       "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
483 	       (unsigned long long) pkt->dring_ident,
484 	       pkt->num_descr, pkt->descr_size, pkt->options,
485 	       pkt->num_cookies);
486 
487 	dr = &vio->drings[VIO_DRIVER_TX_RING];
488 
489 	if (!(vio->dr_state & VIO_DR_STATE_TXREQ))
490 		return handshake_failure(vio);
491 
492 	dr->ident = pkt->dring_ident;
493 	vio->dr_state |= VIO_DR_STATE_TXREG;
494 
495 	if (all_drings_registered(vio)) {
496 		if (send_rdx(vio) < 0)
497 			return handshake_failure(vio);
498 		vio->hs_state = VIO_HS_SENT_RDX;
499 	}
500 	return 0;
501 }
502 
503 static int process_dreg_nack(struct vio_driver_state *vio,
504 			     struct vio_dring_register *pkt)
505 {
506 	viodbg(HS, "GOT DRING_REG NACK ident[%llx] "
507 	       "ndesc[%u] dsz[%u] opt[0x%x] ncookies[%u]\n",
508 	       (unsigned long long) pkt->dring_ident,
509 	       pkt->num_descr, pkt->descr_size, pkt->options,
510 	       pkt->num_cookies);
511 
512 	return handshake_failure(vio);
513 }
514 
515 static int process_dreg(struct vio_driver_state *vio,
516 			struct vio_dring_register *pkt)
517 {
518 	if (!(vio->hs_state & VIO_HS_GOTVERS))
519 		return handshake_failure(vio);
520 
521 	switch (pkt->tag.stype) {
522 	case VIO_SUBTYPE_INFO:
523 		return process_dreg_info(vio, pkt);
524 
525 	case VIO_SUBTYPE_ACK:
526 		return process_dreg_ack(vio, pkt);
527 
528 	case VIO_SUBTYPE_NACK:
529 		return process_dreg_nack(vio, pkt);
530 
531 	default:
532 		return handshake_failure(vio);
533 	}
534 }
535 
536 static int process_dunreg(struct vio_driver_state *vio,
537 			  struct vio_dring_unregister *pkt)
538 {
539 	struct vio_dring_state *dr = &vio->drings[VIO_DRIVER_RX_RING];
540 
541 	viodbg(HS, "GOT DRING_UNREG\n");
542 
543 	if (pkt->dring_ident != dr->ident)
544 		return 0;
545 
546 	vio->dr_state &= ~VIO_DR_STATE_RXREG;
547 
548 	memset(dr, 0, sizeof(*dr));
549 
550 	kfree(vio->desc_buf);
551 	vio->desc_buf = NULL;
552 	vio->desc_buf_len = 0;
553 
554 	return 0;
555 }
556 
557 static int process_rdx_info(struct vio_driver_state *vio, struct vio_rdx *pkt)
558 {
559 	viodbg(HS, "GOT RDX INFO\n");
560 
561 	pkt->tag.stype = VIO_SUBTYPE_ACK;
562 	viodbg(HS, "SEND RDX ACK\n");
563 	if (send_ctrl(vio, &pkt->tag, sizeof(*pkt)) < 0)
564 		return handshake_failure(vio);
565 
566 	vio->hs_state |= VIO_HS_SENT_RDX_ACK;
567 	return 0;
568 }
569 
570 static int process_rdx_ack(struct vio_driver_state *vio, struct vio_rdx *pkt)
571 {
572 	viodbg(HS, "GOT RDX ACK\n");
573 
574 	if (!(vio->hs_state & VIO_HS_SENT_RDX))
575 		return handshake_failure(vio);
576 
577 	vio->hs_state |= VIO_HS_GOT_RDX_ACK;
578 	return 0;
579 }
580 
581 static int process_rdx_nack(struct vio_driver_state *vio, struct vio_rdx *pkt)
582 {
583 	viodbg(HS, "GOT RDX NACK\n");
584 
585 	return handshake_failure(vio);
586 }
587 
588 static int process_rdx(struct vio_driver_state *vio, struct vio_rdx *pkt)
589 {
590 	if (!all_drings_registered(vio))
591 		handshake_failure(vio);
592 
593 	switch (pkt->tag.stype) {
594 	case VIO_SUBTYPE_INFO:
595 		return process_rdx_info(vio, pkt);
596 
597 	case VIO_SUBTYPE_ACK:
598 		return process_rdx_ack(vio, pkt);
599 
600 	case VIO_SUBTYPE_NACK:
601 		return process_rdx_nack(vio, pkt);
602 
603 	default:
604 		return handshake_failure(vio);
605 	}
606 }
607 
608 int vio_control_pkt_engine(struct vio_driver_state *vio, void *pkt)
609 {
610 	struct vio_msg_tag *tag = pkt;
611 	u8 prev_state = vio->hs_state;
612 	int err;
613 
614 	switch (tag->stype_env) {
615 	case VIO_VER_INFO:
616 		err = process_ver(vio, pkt);
617 		break;
618 
619 	case VIO_ATTR_INFO:
620 		err = process_attr(vio, pkt);
621 		break;
622 
623 	case VIO_DRING_REG:
624 		err = process_dreg(vio, pkt);
625 		break;
626 
627 	case VIO_DRING_UNREG:
628 		err = process_dunreg(vio, pkt);
629 		break;
630 
631 	case VIO_RDX:
632 		err = process_rdx(vio, pkt);
633 		break;
634 
635 	default:
636 		err = process_unknown(vio, pkt);
637 		break;
638 	}
639 	if (!err &&
640 	    vio->hs_state != prev_state &&
641 	    (vio->hs_state & VIO_HS_COMPLETE))
642 		vio->ops->handshake_complete(vio);
643 
644 	return err;
645 }
646 EXPORT_SYMBOL(vio_control_pkt_engine);
647 
648 void vio_conn_reset(struct vio_driver_state *vio)
649 {
650 }
651 EXPORT_SYMBOL(vio_conn_reset);
652 
653 /* The issue is that the Solaris virtual disk server just mirrors the
654  * SID values it gets from the client peer.  So we work around that
655  * here in vio_{validate,send}_sid() so that the drivers don't need
656  * to be aware of this crap.
657  */
658 int vio_validate_sid(struct vio_driver_state *vio, struct vio_msg_tag *tp)
659 {
660 	u32 sid;
661 
662 	/* Always let VERSION+INFO packets through unchecked, they
663 	 * define the new SID.
664 	 */
665 	if (tp->type == VIO_TYPE_CTRL &&
666 	    tp->stype == VIO_SUBTYPE_INFO &&
667 	    tp->stype_env == VIO_VER_INFO)
668 		return 0;
669 
670 	/* Ok, now figure out which SID to use.  */
671 	switch (vio->dev_class) {
672 	case VDEV_NETWORK:
673 	case VDEV_NETWORK_SWITCH:
674 	case VDEV_DISK_SERVER:
675 	default:
676 		sid = vio->_peer_sid;
677 		break;
678 
679 	case VDEV_DISK:
680 		sid = vio->_local_sid;
681 		break;
682 	}
683 
684 	if (sid == tp->sid)
685 		return 0;
686 	viodbg(DATA, "BAD SID tag->sid[%08x] peer_sid[%08x] local_sid[%08x]\n",
687 	       tp->sid, vio->_peer_sid, vio->_local_sid);
688 	return -EINVAL;
689 }
690 EXPORT_SYMBOL(vio_validate_sid);
691 
692 u32 vio_send_sid(struct vio_driver_state *vio)
693 {
694 	switch (vio->dev_class) {
695 	case VDEV_NETWORK:
696 	case VDEV_NETWORK_SWITCH:
697 	case VDEV_DISK:
698 	default:
699 		return vio->_local_sid;
700 
701 	case VDEV_DISK_SERVER:
702 		return vio->_peer_sid;
703 	}
704 }
705 EXPORT_SYMBOL(vio_send_sid);
706 
707 int vio_ldc_alloc(struct vio_driver_state *vio,
708 			 struct ldc_channel_config *base_cfg,
709 			 void *event_arg)
710 {
711 	struct ldc_channel_config cfg = *base_cfg;
712 	struct ldc_channel *lp;
713 
714 	cfg.tx_irq = vio->vdev->tx_irq;
715 	cfg.rx_irq = vio->vdev->rx_irq;
716 
717 	lp = ldc_alloc(vio->vdev->channel_id, &cfg, event_arg);
718 	if (IS_ERR(lp))
719 		return PTR_ERR(lp);
720 
721 	vio->lp = lp;
722 
723 	return 0;
724 }
725 EXPORT_SYMBOL(vio_ldc_alloc);
726 
727 void vio_ldc_free(struct vio_driver_state *vio)
728 {
729 	ldc_free(vio->lp);
730 	vio->lp = NULL;
731 
732 	kfree(vio->desc_buf);
733 	vio->desc_buf = NULL;
734 	vio->desc_buf_len = 0;
735 }
736 EXPORT_SYMBOL(vio_ldc_free);
737 
738 void vio_port_up(struct vio_driver_state *vio)
739 {
740 	unsigned long flags;
741 	int err, state;
742 
743 	spin_lock_irqsave(&vio->lock, flags);
744 
745 	state = ldc_state(vio->lp);
746 
747 	err = 0;
748 	if (state == LDC_STATE_INIT) {
749 		err = ldc_bind(vio->lp, vio->name);
750 		if (err)
751 			printk(KERN_WARNING "%s: Port %lu bind failed, "
752 			       "err=%d\n",
753 			       vio->name, vio->vdev->channel_id, err);
754 	}
755 
756 	if (!err) {
757 		err = ldc_connect(vio->lp);
758 		if (err)
759 			printk(KERN_WARNING "%s: Port %lu connect failed, "
760 			       "err=%d\n",
761 			       vio->name, vio->vdev->channel_id, err);
762 	}
763 	if (err) {
764 		unsigned long expires = jiffies + HZ;
765 
766 		expires = round_jiffies(expires);
767 		mod_timer(&vio->timer, expires);
768 	}
769 
770 	spin_unlock_irqrestore(&vio->lock, flags);
771 }
772 EXPORT_SYMBOL(vio_port_up);
773 
774 static void vio_port_timer(unsigned long _arg)
775 {
776 	struct vio_driver_state *vio = (struct vio_driver_state *) _arg;
777 
778 	vio_port_up(vio);
779 }
780 
781 int vio_driver_init(struct vio_driver_state *vio, struct vio_dev *vdev,
782 		    u8 dev_class, struct vio_version *ver_table,
783 		    int ver_table_size, struct vio_driver_ops *ops,
784 		    char *name)
785 {
786 	switch (dev_class) {
787 	case VDEV_NETWORK:
788 	case VDEV_NETWORK_SWITCH:
789 	case VDEV_DISK:
790 	case VDEV_DISK_SERVER:
791 		break;
792 
793 	default:
794 		return -EINVAL;
795 	}
796 
797 	if (!ops->send_attr ||
798 	    !ops->handle_attr ||
799 	    !ops->handshake_complete)
800 		return -EINVAL;
801 
802 	if (!ver_table || ver_table_size < 0)
803 		return -EINVAL;
804 
805 	if (!name)
806 		return -EINVAL;
807 
808 	spin_lock_init(&vio->lock);
809 
810 	vio->name = name;
811 
812 	vio->dev_class = dev_class;
813 	vio->vdev = vdev;
814 
815 	vio->ver_table = ver_table;
816 	vio->ver_table_entries = ver_table_size;
817 
818 	vio->ops = ops;
819 
820 	setup_timer(&vio->timer, vio_port_timer, (unsigned long) vio);
821 
822 	return 0;
823 }
824 EXPORT_SYMBOL(vio_driver_init);
825