1 /*
2  * Copyright (c) 2005 Intel Inc. All rights reserved.
3  * Copyright (c) 2005-2006 Voltaire, Inc. All rights reserved.
4  * Copyright (c) 2014 Intel Corporation.  All rights reserved.
5  *
6  * This software is available to you under a choice of one of two
7  * licenses.  You may choose to be licensed under the terms of the GNU
8  * General Public License (GPL) Version 2, available from the file
9  * COPYING in the main directory of this source tree, or the
10  * OpenIB.org BSD license below:
11  *
12  *     Redistribution and use in source and binary forms, with or
13  *     without modification, are permitted provided that the following
14  *     conditions are met:
15  *
16  *      - Redistributions of source code must retain the above
17  *        copyright notice, this list of conditions and the following
18  *        disclaimer.
19  *
20  *      - Redistributions in binary form must reproduce the above
21  *        copyright notice, this list of conditions and the following
22  *        disclaimer in the documentation and/or other materials
23  *        provided with the distribution.
24  *
25  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32  * SOFTWARE.
33  */
34 
35 #include <linux/slab.h>
36 
37 #include "mad_priv.h"
38 #include "mad_rmpp.h"
39 
40 enum rmpp_state {
41 	RMPP_STATE_ACTIVE,
42 	RMPP_STATE_TIMEOUT,
43 	RMPP_STATE_COMPLETE
44 };
45 
46 struct mad_rmpp_recv {
47 	struct ib_mad_agent_private *agent;
48 	struct list_head list;
49 	struct delayed_work timeout_work;
50 	struct delayed_work cleanup_work;
51 	struct completion comp;
52 	enum rmpp_state state;
53 	spinlock_t lock;
54 	refcount_t refcount;
55 
56 	struct ib_ah *ah;
57 	struct ib_mad_recv_wc *rmpp_wc;
58 	struct ib_mad_recv_buf *cur_seg_buf;
59 	int last_ack;
60 	int seg_num;
61 	int newwin;
62 	int repwin;
63 
64 	__be64 tid;
65 	u32 src_qp;
66 	u32 slid;
67 	u8 mgmt_class;
68 	u8 class_version;
69 	u8 method;
70 	u8 base_version;
71 };
72 
73 static inline void deref_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
74 {
75 	if (refcount_dec_and_test(&rmpp_recv->refcount))
76 		complete(&rmpp_recv->comp);
77 }
78 
79 static void destroy_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
80 {
81 	deref_rmpp_recv(rmpp_recv);
82 	wait_for_completion(&rmpp_recv->comp);
83 	rdma_destroy_ah(rmpp_recv->ah, RDMA_DESTROY_AH_SLEEPABLE);
84 	kfree(rmpp_recv);
85 }
86 
87 void ib_cancel_rmpp_recvs(struct ib_mad_agent_private *agent)
88 {
89 	struct mad_rmpp_recv *rmpp_recv, *temp_rmpp_recv;
90 	unsigned long flags;
91 
92 	spin_lock_irqsave(&agent->lock, flags);
93 	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
94 		cancel_delayed_work(&rmpp_recv->timeout_work);
95 		cancel_delayed_work(&rmpp_recv->cleanup_work);
96 	}
97 	spin_unlock_irqrestore(&agent->lock, flags);
98 
99 	flush_workqueue(agent->qp_info->port_priv->wq);
100 
101 	list_for_each_entry_safe(rmpp_recv, temp_rmpp_recv,
102 				 &agent->rmpp_list, list) {
103 		list_del(&rmpp_recv->list);
104 		if (rmpp_recv->state != RMPP_STATE_COMPLETE)
105 			ib_free_recv_mad(rmpp_recv->rmpp_wc);
106 		destroy_rmpp_recv(rmpp_recv);
107 	}
108 }
109 
110 static void format_ack(struct ib_mad_send_buf *msg,
111 		       struct ib_rmpp_mad *data,
112 		       struct mad_rmpp_recv *rmpp_recv)
113 {
114 	struct ib_rmpp_mad *ack = msg->mad;
115 	unsigned long flags;
116 
117 	memcpy(ack, &data->mad_hdr, msg->hdr_len);
118 
119 	ack->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
120 	ack->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ACK;
121 	ib_set_rmpp_flags(&ack->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
122 
123 	spin_lock_irqsave(&rmpp_recv->lock, flags);
124 	rmpp_recv->last_ack = rmpp_recv->seg_num;
125 	ack->rmpp_hdr.seg_num = cpu_to_be32(rmpp_recv->seg_num);
126 	ack->rmpp_hdr.paylen_newwin = cpu_to_be32(rmpp_recv->newwin);
127 	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
128 }
129 
130 static void ack_recv(struct mad_rmpp_recv *rmpp_recv,
131 		     struct ib_mad_recv_wc *recv_wc)
132 {
133 	struct ib_mad_send_buf *msg;
134 	int ret, hdr_len;
135 
136 	hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
137 	msg = ib_create_send_mad(&rmpp_recv->agent->agent, recv_wc->wc->src_qp,
138 				 recv_wc->wc->pkey_index, 1, hdr_len,
139 				 0, GFP_KERNEL,
140 				 IB_MGMT_BASE_VERSION);
141 	if (IS_ERR(msg))
142 		return;
143 
144 	format_ack(msg, (struct ib_rmpp_mad *) recv_wc->recv_buf.mad, rmpp_recv);
145 	msg->ah = rmpp_recv->ah;
146 	ret = ib_post_send_mad(msg, NULL);
147 	if (ret)
148 		ib_free_send_mad(msg);
149 }
150 
151 static struct ib_mad_send_buf *alloc_response_msg(struct ib_mad_agent *agent,
152 						  struct ib_mad_recv_wc *recv_wc)
153 {
154 	struct ib_mad_send_buf *msg;
155 	struct ib_ah *ah;
156 	int hdr_len;
157 
158 	ah = ib_create_ah_from_wc(agent->qp->pd, recv_wc->wc,
159 				  recv_wc->recv_buf.grh, agent->port_num);
160 	if (IS_ERR(ah))
161 		return (void *) ah;
162 
163 	hdr_len = ib_get_mad_data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
164 	msg = ib_create_send_mad(agent, recv_wc->wc->src_qp,
165 				 recv_wc->wc->pkey_index, 1,
166 				 hdr_len, 0, GFP_KERNEL,
167 				 IB_MGMT_BASE_VERSION);
168 	if (IS_ERR(msg))
169 		rdma_destroy_ah(ah, RDMA_DESTROY_AH_SLEEPABLE);
170 	else {
171 		msg->ah = ah;
172 		msg->context[0] = ah;
173 	}
174 
175 	return msg;
176 }
177 
178 static void ack_ds_ack(struct ib_mad_agent_private *agent,
179 		       struct ib_mad_recv_wc *recv_wc)
180 {
181 	struct ib_mad_send_buf *msg;
182 	struct ib_rmpp_mad *rmpp_mad;
183 	int ret;
184 
185 	msg = alloc_response_msg(&agent->agent, recv_wc);
186 	if (IS_ERR(msg))
187 		return;
188 
189 	rmpp_mad = msg->mad;
190 	memcpy(rmpp_mad, recv_wc->recv_buf.mad, msg->hdr_len);
191 
192 	rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
193 	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
194 	rmpp_mad->rmpp_hdr.seg_num = 0;
195 	rmpp_mad->rmpp_hdr.paylen_newwin = cpu_to_be32(1);
196 
197 	ret = ib_post_send_mad(msg, NULL);
198 	if (ret) {
199 		rdma_destroy_ah(msg->ah, RDMA_DESTROY_AH_SLEEPABLE);
200 		ib_free_send_mad(msg);
201 	}
202 }
203 
204 void ib_rmpp_send_handler(struct ib_mad_send_wc *mad_send_wc)
205 {
206 	if (mad_send_wc->send_buf->context[0] == mad_send_wc->send_buf->ah)
207 		rdma_destroy_ah(mad_send_wc->send_buf->ah,
208 				RDMA_DESTROY_AH_SLEEPABLE);
209 	ib_free_send_mad(mad_send_wc->send_buf);
210 }
211 
212 static void nack_recv(struct ib_mad_agent_private *agent,
213 		      struct ib_mad_recv_wc *recv_wc, u8 rmpp_status)
214 {
215 	struct ib_mad_send_buf *msg;
216 	struct ib_rmpp_mad *rmpp_mad;
217 	int ret;
218 
219 	msg = alloc_response_msg(&agent->agent, recv_wc);
220 	if (IS_ERR(msg))
221 		return;
222 
223 	rmpp_mad = msg->mad;
224 	memcpy(rmpp_mad, recv_wc->recv_buf.mad, msg->hdr_len);
225 
226 	rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
227 	rmpp_mad->rmpp_hdr.rmpp_version = IB_MGMT_RMPP_VERSION;
228 	rmpp_mad->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ABORT;
229 	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
230 	rmpp_mad->rmpp_hdr.rmpp_status = rmpp_status;
231 	rmpp_mad->rmpp_hdr.seg_num = 0;
232 	rmpp_mad->rmpp_hdr.paylen_newwin = 0;
233 
234 	ret = ib_post_send_mad(msg, NULL);
235 	if (ret) {
236 		rdma_destroy_ah(msg->ah, RDMA_DESTROY_AH_SLEEPABLE);
237 		ib_free_send_mad(msg);
238 	}
239 }
240 
241 static void recv_timeout_handler(struct work_struct *work)
242 {
243 	struct mad_rmpp_recv *rmpp_recv =
244 		container_of(work, struct mad_rmpp_recv, timeout_work.work);
245 	struct ib_mad_recv_wc *rmpp_wc;
246 	unsigned long flags;
247 
248 	spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
249 	if (rmpp_recv->state != RMPP_STATE_ACTIVE) {
250 		spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
251 		return;
252 	}
253 	rmpp_recv->state = RMPP_STATE_TIMEOUT;
254 	list_del(&rmpp_recv->list);
255 	spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
256 
257 	rmpp_wc = rmpp_recv->rmpp_wc;
258 	nack_recv(rmpp_recv->agent, rmpp_wc, IB_MGMT_RMPP_STATUS_T2L);
259 	destroy_rmpp_recv(rmpp_recv);
260 	ib_free_recv_mad(rmpp_wc);
261 }
262 
263 static void recv_cleanup_handler(struct work_struct *work)
264 {
265 	struct mad_rmpp_recv *rmpp_recv =
266 		container_of(work, struct mad_rmpp_recv, cleanup_work.work);
267 	unsigned long flags;
268 
269 	spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
270 	list_del(&rmpp_recv->list);
271 	spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
272 	destroy_rmpp_recv(rmpp_recv);
273 }
274 
275 static struct mad_rmpp_recv *
276 create_rmpp_recv(struct ib_mad_agent_private *agent,
277 		 struct ib_mad_recv_wc *mad_recv_wc)
278 {
279 	struct mad_rmpp_recv *rmpp_recv;
280 	struct ib_mad_hdr *mad_hdr;
281 
282 	rmpp_recv = kmalloc(sizeof *rmpp_recv, GFP_KERNEL);
283 	if (!rmpp_recv)
284 		return NULL;
285 
286 	rmpp_recv->ah = ib_create_ah_from_wc(agent->agent.qp->pd,
287 					     mad_recv_wc->wc,
288 					     mad_recv_wc->recv_buf.grh,
289 					     agent->agent.port_num);
290 	if (IS_ERR(rmpp_recv->ah))
291 		goto error;
292 
293 	rmpp_recv->agent = agent;
294 	init_completion(&rmpp_recv->comp);
295 	INIT_DELAYED_WORK(&rmpp_recv->timeout_work, recv_timeout_handler);
296 	INIT_DELAYED_WORK(&rmpp_recv->cleanup_work, recv_cleanup_handler);
297 	spin_lock_init(&rmpp_recv->lock);
298 	rmpp_recv->state = RMPP_STATE_ACTIVE;
299 	refcount_set(&rmpp_recv->refcount, 1);
300 
301 	rmpp_recv->rmpp_wc = mad_recv_wc;
302 	rmpp_recv->cur_seg_buf = &mad_recv_wc->recv_buf;
303 	rmpp_recv->newwin = 1;
304 	rmpp_recv->seg_num = 1;
305 	rmpp_recv->last_ack = 0;
306 	rmpp_recv->repwin = 1;
307 
308 	mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
309 	rmpp_recv->tid = mad_hdr->tid;
310 	rmpp_recv->src_qp = mad_recv_wc->wc->src_qp;
311 	rmpp_recv->slid = mad_recv_wc->wc->slid;
312 	rmpp_recv->mgmt_class = mad_hdr->mgmt_class;
313 	rmpp_recv->class_version = mad_hdr->class_version;
314 	rmpp_recv->method  = mad_hdr->method;
315 	rmpp_recv->base_version  = mad_hdr->base_version;
316 	return rmpp_recv;
317 
318 error:	kfree(rmpp_recv);
319 	return NULL;
320 }
321 
322 static struct mad_rmpp_recv *
323 find_rmpp_recv(struct ib_mad_agent_private *agent,
324 	       struct ib_mad_recv_wc *mad_recv_wc)
325 {
326 	struct mad_rmpp_recv *rmpp_recv;
327 	struct ib_mad_hdr *mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
328 
329 	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
330 		if (rmpp_recv->tid == mad_hdr->tid &&
331 		    rmpp_recv->src_qp == mad_recv_wc->wc->src_qp &&
332 		    rmpp_recv->slid == mad_recv_wc->wc->slid &&
333 		    rmpp_recv->mgmt_class == mad_hdr->mgmt_class &&
334 		    rmpp_recv->class_version == mad_hdr->class_version &&
335 		    rmpp_recv->method == mad_hdr->method)
336 			return rmpp_recv;
337 	}
338 	return NULL;
339 }
340 
341 static struct mad_rmpp_recv *
342 acquire_rmpp_recv(struct ib_mad_agent_private *agent,
343 		  struct ib_mad_recv_wc *mad_recv_wc)
344 {
345 	struct mad_rmpp_recv *rmpp_recv;
346 	unsigned long flags;
347 
348 	spin_lock_irqsave(&agent->lock, flags);
349 	rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
350 	if (rmpp_recv)
351 		refcount_inc(&rmpp_recv->refcount);
352 	spin_unlock_irqrestore(&agent->lock, flags);
353 	return rmpp_recv;
354 }
355 
356 static struct mad_rmpp_recv *
357 insert_rmpp_recv(struct ib_mad_agent_private *agent,
358 		 struct mad_rmpp_recv *rmpp_recv)
359 {
360 	struct mad_rmpp_recv *cur_rmpp_recv;
361 
362 	cur_rmpp_recv = find_rmpp_recv(agent, rmpp_recv->rmpp_wc);
363 	if (!cur_rmpp_recv)
364 		list_add_tail(&rmpp_recv->list, &agent->rmpp_list);
365 
366 	return cur_rmpp_recv;
367 }
368 
369 static inline int get_last_flag(struct ib_mad_recv_buf *seg)
370 {
371 	struct ib_rmpp_mad *rmpp_mad;
372 
373 	rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
374 	return ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) & IB_MGMT_RMPP_FLAG_LAST;
375 }
376 
377 static inline int get_seg_num(struct ib_mad_recv_buf *seg)
378 {
379 	struct ib_rmpp_mad *rmpp_mad;
380 
381 	rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
382 	return be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
383 }
384 
385 static inline struct ib_mad_recv_buf * get_next_seg(struct list_head *rmpp_list,
386 						    struct ib_mad_recv_buf *seg)
387 {
388 	if (seg->list.next == rmpp_list)
389 		return NULL;
390 
391 	return container_of(seg->list.next, struct ib_mad_recv_buf, list);
392 }
393 
394 static inline int window_size(struct ib_mad_agent_private *agent)
395 {
396 	return max(agent->qp_info->recv_queue.max_active >> 3, 1);
397 }
398 
399 static struct ib_mad_recv_buf * find_seg_location(struct list_head *rmpp_list,
400 						  int seg_num)
401 {
402 	struct ib_mad_recv_buf *seg_buf;
403 	int cur_seg_num;
404 
405 	list_for_each_entry_reverse(seg_buf, rmpp_list, list) {
406 		cur_seg_num = get_seg_num(seg_buf);
407 		if (seg_num > cur_seg_num)
408 			return seg_buf;
409 		if (seg_num == cur_seg_num)
410 			break;
411 	}
412 	return NULL;
413 }
414 
415 static void update_seg_num(struct mad_rmpp_recv *rmpp_recv,
416 			   struct ib_mad_recv_buf *new_buf)
417 {
418 	struct list_head *rmpp_list = &rmpp_recv->rmpp_wc->rmpp_list;
419 
420 	while (new_buf && (get_seg_num(new_buf) == rmpp_recv->seg_num + 1)) {
421 		rmpp_recv->cur_seg_buf = new_buf;
422 		rmpp_recv->seg_num++;
423 		new_buf = get_next_seg(rmpp_list, new_buf);
424 	}
425 }
426 
427 static inline int get_mad_len(struct mad_rmpp_recv *rmpp_recv)
428 {
429 	struct ib_rmpp_mad *rmpp_mad;
430 	int hdr_size, data_size, pad;
431 	bool opa = rdma_cap_opa_mad(rmpp_recv->agent->qp_info->port_priv->device,
432 				    rmpp_recv->agent->qp_info->port_priv->port_num);
433 
434 	rmpp_mad = (struct ib_rmpp_mad *)rmpp_recv->cur_seg_buf->mad;
435 
436 	hdr_size = ib_get_mad_data_offset(rmpp_mad->mad_hdr.mgmt_class);
437 	if (opa && rmpp_recv->base_version == OPA_MGMT_BASE_VERSION) {
438 		data_size = sizeof(struct opa_rmpp_mad) - hdr_size;
439 		pad = OPA_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
440 		if (pad > OPA_MGMT_RMPP_DATA || pad < 0)
441 			pad = 0;
442 	} else {
443 		data_size = sizeof(struct ib_rmpp_mad) - hdr_size;
444 		pad = IB_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
445 		if (pad > IB_MGMT_RMPP_DATA || pad < 0)
446 			pad = 0;
447 	}
448 
449 	return hdr_size + rmpp_recv->seg_num * data_size - pad;
450 }
451 
452 static struct ib_mad_recv_wc * complete_rmpp(struct mad_rmpp_recv *rmpp_recv)
453 {
454 	struct ib_mad_recv_wc *rmpp_wc;
455 
456 	ack_recv(rmpp_recv, rmpp_recv->rmpp_wc);
457 	if (rmpp_recv->seg_num > 1)
458 		cancel_delayed_work(&rmpp_recv->timeout_work);
459 
460 	rmpp_wc = rmpp_recv->rmpp_wc;
461 	rmpp_wc->mad_len = get_mad_len(rmpp_recv);
462 	/* 10 seconds until we can find the packet lifetime */
463 	queue_delayed_work(rmpp_recv->agent->qp_info->port_priv->wq,
464 			   &rmpp_recv->cleanup_work, msecs_to_jiffies(10000));
465 	return rmpp_wc;
466 }
467 
468 static struct ib_mad_recv_wc *
469 continue_rmpp(struct ib_mad_agent_private *agent,
470 	      struct ib_mad_recv_wc *mad_recv_wc)
471 {
472 	struct mad_rmpp_recv *rmpp_recv;
473 	struct ib_mad_recv_buf *prev_buf;
474 	struct ib_mad_recv_wc *done_wc;
475 	int seg_num;
476 	unsigned long flags;
477 
478 	rmpp_recv = acquire_rmpp_recv(agent, mad_recv_wc);
479 	if (!rmpp_recv)
480 		goto drop1;
481 
482 	seg_num = get_seg_num(&mad_recv_wc->recv_buf);
483 
484 	spin_lock_irqsave(&rmpp_recv->lock, flags);
485 	if ((rmpp_recv->state == RMPP_STATE_TIMEOUT) ||
486 	    (seg_num > rmpp_recv->newwin))
487 		goto drop3;
488 
489 	if ((seg_num <= rmpp_recv->last_ack) ||
490 	    (rmpp_recv->state == RMPP_STATE_COMPLETE)) {
491 		spin_unlock_irqrestore(&rmpp_recv->lock, flags);
492 		ack_recv(rmpp_recv, mad_recv_wc);
493 		goto drop2;
494 	}
495 
496 	prev_buf = find_seg_location(&rmpp_recv->rmpp_wc->rmpp_list, seg_num);
497 	if (!prev_buf)
498 		goto drop3;
499 
500 	done_wc = NULL;
501 	list_add(&mad_recv_wc->recv_buf.list, &prev_buf->list);
502 	if (rmpp_recv->cur_seg_buf == prev_buf) {
503 		update_seg_num(rmpp_recv, &mad_recv_wc->recv_buf);
504 		if (get_last_flag(rmpp_recv->cur_seg_buf)) {
505 			rmpp_recv->state = RMPP_STATE_COMPLETE;
506 			spin_unlock_irqrestore(&rmpp_recv->lock, flags);
507 			done_wc = complete_rmpp(rmpp_recv);
508 			goto out;
509 		} else if (rmpp_recv->seg_num == rmpp_recv->newwin) {
510 			rmpp_recv->newwin += window_size(agent);
511 			spin_unlock_irqrestore(&rmpp_recv->lock, flags);
512 			ack_recv(rmpp_recv, mad_recv_wc);
513 			goto out;
514 		}
515 	}
516 	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
517 out:
518 	deref_rmpp_recv(rmpp_recv);
519 	return done_wc;
520 
521 drop3:	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
522 drop2:	deref_rmpp_recv(rmpp_recv);
523 drop1:	ib_free_recv_mad(mad_recv_wc);
524 	return NULL;
525 }
526 
527 static struct ib_mad_recv_wc *
528 start_rmpp(struct ib_mad_agent_private *agent,
529 	   struct ib_mad_recv_wc *mad_recv_wc)
530 {
531 	struct mad_rmpp_recv *rmpp_recv;
532 	unsigned long flags;
533 
534 	rmpp_recv = create_rmpp_recv(agent, mad_recv_wc);
535 	if (!rmpp_recv) {
536 		ib_free_recv_mad(mad_recv_wc);
537 		return NULL;
538 	}
539 
540 	spin_lock_irqsave(&agent->lock, flags);
541 	if (insert_rmpp_recv(agent, rmpp_recv)) {
542 		spin_unlock_irqrestore(&agent->lock, flags);
543 		/* duplicate first MAD */
544 		destroy_rmpp_recv(rmpp_recv);
545 		return continue_rmpp(agent, mad_recv_wc);
546 	}
547 	refcount_inc(&rmpp_recv->refcount);
548 
549 	if (get_last_flag(&mad_recv_wc->recv_buf)) {
550 		rmpp_recv->state = RMPP_STATE_COMPLETE;
551 		spin_unlock_irqrestore(&agent->lock, flags);
552 		complete_rmpp(rmpp_recv);
553 	} else {
554 		spin_unlock_irqrestore(&agent->lock, flags);
555 		/* 40 seconds until we can find the packet lifetimes */
556 		queue_delayed_work(agent->qp_info->port_priv->wq,
557 				   &rmpp_recv->timeout_work,
558 				   msecs_to_jiffies(40000));
559 		rmpp_recv->newwin += window_size(agent);
560 		ack_recv(rmpp_recv, mad_recv_wc);
561 		mad_recv_wc = NULL;
562 	}
563 	deref_rmpp_recv(rmpp_recv);
564 	return mad_recv_wc;
565 }
566 
567 static int send_next_seg(struct ib_mad_send_wr_private *mad_send_wr)
568 {
569 	struct ib_rmpp_mad *rmpp_mad;
570 	int timeout;
571 	u32 paylen = 0;
572 
573 	rmpp_mad = mad_send_wr->send_buf.mad;
574 	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
575 	rmpp_mad->rmpp_hdr.seg_num = cpu_to_be32(++mad_send_wr->seg_num);
576 
577 	if (mad_send_wr->seg_num == 1) {
578 		rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_FIRST;
579 		paylen = (mad_send_wr->send_buf.seg_count *
580 			  mad_send_wr->send_buf.seg_rmpp_size) -
581 			  mad_send_wr->pad;
582 	}
583 
584 	if (mad_send_wr->seg_num == mad_send_wr->send_buf.seg_count) {
585 		rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_LAST;
586 		paylen = mad_send_wr->send_buf.seg_rmpp_size - mad_send_wr->pad;
587 	}
588 	rmpp_mad->rmpp_hdr.paylen_newwin = cpu_to_be32(paylen);
589 
590 	/* 2 seconds for an ACK until we can find the packet lifetime */
591 	timeout = mad_send_wr->send_buf.timeout_ms;
592 	if (!timeout || timeout > 2000)
593 		mad_send_wr->timeout = msecs_to_jiffies(2000);
594 
595 	return ib_send_mad(mad_send_wr);
596 }
597 
598 static void abort_send(struct ib_mad_agent_private *agent,
599 		       struct ib_mad_recv_wc *mad_recv_wc, u8 rmpp_status)
600 {
601 	struct ib_mad_send_wr_private *mad_send_wr;
602 	struct ib_mad_send_wc wc;
603 	unsigned long flags;
604 
605 	spin_lock_irqsave(&agent->lock, flags);
606 	mad_send_wr = ib_find_send_mad(agent, mad_recv_wc);
607 	if (!mad_send_wr)
608 		goto out;	/* Unmatched send */
609 
610 	if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) ||
611 	    (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
612 		goto out;	/* Send is already done */
613 
614 	ib_mark_mad_done(mad_send_wr);
615 	spin_unlock_irqrestore(&agent->lock, flags);
616 
617 	wc.status = IB_WC_REM_ABORT_ERR;
618 	wc.vendor_err = rmpp_status;
619 	wc.send_buf = &mad_send_wr->send_buf;
620 	ib_mad_complete_send_wr(mad_send_wr, &wc);
621 	return;
622 out:
623 	spin_unlock_irqrestore(&agent->lock, flags);
624 }
625 
626 static inline void adjust_last_ack(struct ib_mad_send_wr_private *wr,
627 				   int seg_num)
628 {
629 	struct list_head *list;
630 
631 	wr->last_ack = seg_num;
632 	list = &wr->last_ack_seg->list;
633 	list_for_each_entry(wr->last_ack_seg, list, list)
634 		if (wr->last_ack_seg->num == seg_num)
635 			break;
636 }
637 
638 static void process_ds_ack(struct ib_mad_agent_private *agent,
639 			   struct ib_mad_recv_wc *mad_recv_wc, int newwin)
640 {
641 	struct mad_rmpp_recv *rmpp_recv;
642 
643 	rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
644 	if (rmpp_recv && rmpp_recv->state == RMPP_STATE_COMPLETE)
645 		rmpp_recv->repwin = newwin;
646 }
647 
648 static void process_rmpp_ack(struct ib_mad_agent_private *agent,
649 			     struct ib_mad_recv_wc *mad_recv_wc)
650 {
651 	struct ib_mad_send_wr_private *mad_send_wr;
652 	struct ib_rmpp_mad *rmpp_mad;
653 	unsigned long flags;
654 	int seg_num, newwin, ret;
655 
656 	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
657 	if (rmpp_mad->rmpp_hdr.rmpp_status) {
658 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
659 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
660 		return;
661 	}
662 
663 	seg_num = be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
664 	newwin = be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
665 	if (newwin < seg_num) {
666 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_W2S);
667 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_W2S);
668 		return;
669 	}
670 
671 	spin_lock_irqsave(&agent->lock, flags);
672 	mad_send_wr = ib_find_send_mad(agent, mad_recv_wc);
673 	if (!mad_send_wr) {
674 		if (!seg_num)
675 			process_ds_ack(agent, mad_recv_wc, newwin);
676 		goto out;	/* Unmatched or DS RMPP ACK */
677 	}
678 
679 	if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) &&
680 	    (mad_send_wr->timeout)) {
681 		spin_unlock_irqrestore(&agent->lock, flags);
682 		ack_ds_ack(agent, mad_recv_wc);
683 		return;		/* Repeated ACK for DS RMPP transaction */
684 	}
685 
686 	if ((mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) ||
687 	    (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
688 		goto out;	/* Send is already done */
689 
690 	if (seg_num > mad_send_wr->send_buf.seg_count ||
691 	    seg_num > mad_send_wr->newwin) {
692 		spin_unlock_irqrestore(&agent->lock, flags);
693 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_S2B);
694 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_S2B);
695 		return;
696 	}
697 
698 	if (newwin < mad_send_wr->newwin || seg_num < mad_send_wr->last_ack)
699 		goto out;	/* Old ACK */
700 
701 	if (seg_num > mad_send_wr->last_ack) {
702 		adjust_last_ack(mad_send_wr, seg_num);
703 		mad_send_wr->retries_left = mad_send_wr->max_retries;
704 	}
705 	mad_send_wr->newwin = newwin;
706 	if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) {
707 		/* If no response is expected, the ACK completes the send */
708 		if (!mad_send_wr->send_buf.timeout_ms) {
709 			struct ib_mad_send_wc wc;
710 
711 			ib_mark_mad_done(mad_send_wr);
712 			spin_unlock_irqrestore(&agent->lock, flags);
713 
714 			wc.status = IB_WC_SUCCESS;
715 			wc.vendor_err = 0;
716 			wc.send_buf = &mad_send_wr->send_buf;
717 			ib_mad_complete_send_wr(mad_send_wr, &wc);
718 			return;
719 		}
720 		if (mad_send_wr->refcount == 1)
721 			ib_reset_mad_timeout(mad_send_wr,
722 					     mad_send_wr->send_buf.timeout_ms);
723 		spin_unlock_irqrestore(&agent->lock, flags);
724 		ack_ds_ack(agent, mad_recv_wc);
725 		return;
726 	} else if (mad_send_wr->refcount == 1 &&
727 		   mad_send_wr->seg_num < mad_send_wr->newwin &&
728 		   mad_send_wr->seg_num < mad_send_wr->send_buf.seg_count) {
729 		/* Send failure will just result in a timeout/retry */
730 		ret = send_next_seg(mad_send_wr);
731 		if (ret)
732 			goto out;
733 
734 		mad_send_wr->refcount++;
735 		list_move_tail(&mad_send_wr->agent_list,
736 			      &mad_send_wr->mad_agent_priv->send_list);
737 	}
738 out:
739 	spin_unlock_irqrestore(&agent->lock, flags);
740 }
741 
742 static struct ib_mad_recv_wc *
743 process_rmpp_data(struct ib_mad_agent_private *agent,
744 		  struct ib_mad_recv_wc *mad_recv_wc)
745 {
746 	struct ib_rmpp_hdr *rmpp_hdr;
747 	u8 rmpp_status;
748 
749 	rmpp_hdr = &((struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad)->rmpp_hdr;
750 
751 	if (rmpp_hdr->rmpp_status) {
752 		rmpp_status = IB_MGMT_RMPP_STATUS_BAD_STATUS;
753 		goto bad;
754 	}
755 
756 	if (rmpp_hdr->seg_num == cpu_to_be32(1)) {
757 		if (!(ib_get_rmpp_flags(rmpp_hdr) & IB_MGMT_RMPP_FLAG_FIRST)) {
758 			rmpp_status = IB_MGMT_RMPP_STATUS_BAD_SEG;
759 			goto bad;
760 		}
761 		return start_rmpp(agent, mad_recv_wc);
762 	} else {
763 		if (ib_get_rmpp_flags(rmpp_hdr) & IB_MGMT_RMPP_FLAG_FIRST) {
764 			rmpp_status = IB_MGMT_RMPP_STATUS_BAD_SEG;
765 			goto bad;
766 		}
767 		return continue_rmpp(agent, mad_recv_wc);
768 	}
769 bad:
770 	nack_recv(agent, mad_recv_wc, rmpp_status);
771 	ib_free_recv_mad(mad_recv_wc);
772 	return NULL;
773 }
774 
775 static void process_rmpp_stop(struct ib_mad_agent_private *agent,
776 			      struct ib_mad_recv_wc *mad_recv_wc)
777 {
778 	struct ib_rmpp_mad *rmpp_mad;
779 
780 	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
781 
782 	if (rmpp_mad->rmpp_hdr.rmpp_status != IB_MGMT_RMPP_STATUS_RESX) {
783 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
784 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
785 	} else
786 		abort_send(agent, mad_recv_wc, rmpp_mad->rmpp_hdr.rmpp_status);
787 }
788 
789 static void process_rmpp_abort(struct ib_mad_agent_private *agent,
790 			       struct ib_mad_recv_wc *mad_recv_wc)
791 {
792 	struct ib_rmpp_mad *rmpp_mad;
793 
794 	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
795 
796 	if (rmpp_mad->rmpp_hdr.rmpp_status < IB_MGMT_RMPP_STATUS_ABORT_MIN ||
797 	    rmpp_mad->rmpp_hdr.rmpp_status > IB_MGMT_RMPP_STATUS_ABORT_MAX) {
798 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
799 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BAD_STATUS);
800 	} else
801 		abort_send(agent, mad_recv_wc, rmpp_mad->rmpp_hdr.rmpp_status);
802 }
803 
804 struct ib_mad_recv_wc *
805 ib_process_rmpp_recv_wc(struct ib_mad_agent_private *agent,
806 			struct ib_mad_recv_wc *mad_recv_wc)
807 {
808 	struct ib_rmpp_mad *rmpp_mad;
809 
810 	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
811 	if (!(rmpp_mad->rmpp_hdr.rmpp_rtime_flags & IB_MGMT_RMPP_FLAG_ACTIVE))
812 		return mad_recv_wc;
813 
814 	if (rmpp_mad->rmpp_hdr.rmpp_version != IB_MGMT_RMPP_VERSION) {
815 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_UNV);
816 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_UNV);
817 		goto out;
818 	}
819 
820 	switch (rmpp_mad->rmpp_hdr.rmpp_type) {
821 	case IB_MGMT_RMPP_TYPE_DATA:
822 		return process_rmpp_data(agent, mad_recv_wc);
823 	case IB_MGMT_RMPP_TYPE_ACK:
824 		process_rmpp_ack(agent, mad_recv_wc);
825 		break;
826 	case IB_MGMT_RMPP_TYPE_STOP:
827 		process_rmpp_stop(agent, mad_recv_wc);
828 		break;
829 	case IB_MGMT_RMPP_TYPE_ABORT:
830 		process_rmpp_abort(agent, mad_recv_wc);
831 		break;
832 	default:
833 		abort_send(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BADT);
834 		nack_recv(agent, mad_recv_wc, IB_MGMT_RMPP_STATUS_BADT);
835 		break;
836 	}
837 out:
838 	ib_free_recv_mad(mad_recv_wc);
839 	return NULL;
840 }
841 
842 static int init_newwin(struct ib_mad_send_wr_private *mad_send_wr)
843 {
844 	struct ib_mad_agent_private *agent = mad_send_wr->mad_agent_priv;
845 	struct ib_mad_hdr *mad_hdr = mad_send_wr->send_buf.mad;
846 	struct mad_rmpp_recv *rmpp_recv;
847 	struct rdma_ah_attr ah_attr;
848 	unsigned long flags;
849 	int newwin = 1;
850 
851 	if (!(mad_hdr->method & IB_MGMT_METHOD_RESP))
852 		goto out;
853 
854 	spin_lock_irqsave(&agent->lock, flags);
855 	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
856 		if (rmpp_recv->tid != mad_hdr->tid ||
857 		    rmpp_recv->mgmt_class != mad_hdr->mgmt_class ||
858 		    rmpp_recv->class_version != mad_hdr->class_version ||
859 		    (rmpp_recv->method & IB_MGMT_METHOD_RESP))
860 			continue;
861 
862 		if (rdma_query_ah(mad_send_wr->send_buf.ah, &ah_attr))
863 			continue;
864 
865 		if (rmpp_recv->slid == rdma_ah_get_dlid(&ah_attr)) {
866 			newwin = rmpp_recv->repwin;
867 			break;
868 		}
869 	}
870 	spin_unlock_irqrestore(&agent->lock, flags);
871 out:
872 	return newwin;
873 }
874 
875 int ib_send_rmpp_mad(struct ib_mad_send_wr_private *mad_send_wr)
876 {
877 	struct ib_rmpp_mad *rmpp_mad;
878 	int ret;
879 
880 	rmpp_mad = mad_send_wr->send_buf.mad;
881 	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
882 	      IB_MGMT_RMPP_FLAG_ACTIVE))
883 		return IB_RMPP_RESULT_UNHANDLED;
884 
885 	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA) {
886 		mad_send_wr->seg_num = 1;
887 		return IB_RMPP_RESULT_INTERNAL;
888 	}
889 
890 	mad_send_wr->newwin = init_newwin(mad_send_wr);
891 
892 	/* We need to wait for the final ACK even if there isn't a response */
893 	mad_send_wr->refcount += (mad_send_wr->timeout == 0);
894 	ret = send_next_seg(mad_send_wr);
895 	if (!ret)
896 		return IB_RMPP_RESULT_CONSUMED;
897 	return ret;
898 }
899 
900 int ib_process_rmpp_send_wc(struct ib_mad_send_wr_private *mad_send_wr,
901 			    struct ib_mad_send_wc *mad_send_wc)
902 {
903 	struct ib_rmpp_mad *rmpp_mad;
904 	int ret;
905 
906 	rmpp_mad = mad_send_wr->send_buf.mad;
907 	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
908 	      IB_MGMT_RMPP_FLAG_ACTIVE))
909 		return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */
910 
911 	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA)
912 		return IB_RMPP_RESULT_INTERNAL;	 /* ACK, STOP, or ABORT */
913 
914 	if (mad_send_wc->status != IB_WC_SUCCESS ||
915 	    mad_send_wr->status != IB_WC_SUCCESS)
916 		return IB_RMPP_RESULT_PROCESSED; /* Canceled or send error */
917 
918 	if (!mad_send_wr->timeout)
919 		return IB_RMPP_RESULT_PROCESSED; /* Response received */
920 
921 	if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count) {
922 		mad_send_wr->timeout =
923 			msecs_to_jiffies(mad_send_wr->send_buf.timeout_ms);
924 		return IB_RMPP_RESULT_PROCESSED; /* Send done */
925 	}
926 
927 	if (mad_send_wr->seg_num == mad_send_wr->newwin ||
928 	    mad_send_wr->seg_num == mad_send_wr->send_buf.seg_count)
929 		return IB_RMPP_RESULT_PROCESSED; /* Wait for ACK */
930 
931 	ret = send_next_seg(mad_send_wr);
932 	if (ret) {
933 		mad_send_wc->status = IB_WC_GENERAL_ERR;
934 		return IB_RMPP_RESULT_PROCESSED;
935 	}
936 	return IB_RMPP_RESULT_CONSUMED;
937 }
938 
939 int ib_retry_rmpp(struct ib_mad_send_wr_private *mad_send_wr)
940 {
941 	struct ib_rmpp_mad *rmpp_mad;
942 	int ret;
943 
944 	rmpp_mad = mad_send_wr->send_buf.mad;
945 	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
946 	      IB_MGMT_RMPP_FLAG_ACTIVE))
947 		return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */
948 
949 	if (mad_send_wr->last_ack == mad_send_wr->send_buf.seg_count)
950 		return IB_RMPP_RESULT_PROCESSED;
951 
952 	mad_send_wr->seg_num = mad_send_wr->last_ack;
953 	mad_send_wr->cur_seg = mad_send_wr->last_ack_seg;
954 
955 	ret = send_next_seg(mad_send_wr);
956 	if (ret)
957 		return IB_RMPP_RESULT_PROCESSED;
958 
959 	return IB_RMPP_RESULT_CONSUMED;
960 }
961