xref: /freebsd/sys/ofed/drivers/infiniband/ulp/sdp/sdp_rx.c (revision f81cdf24ba5436367377f7c8e8f51f6df2a75ca7)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause OR GPL-2.0
3  *
4  * Copyright (c) 2009 Mellanox Technologies Ltd.  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 #include "sdp.h"
35 
36 SDP_MODPARAM_INT(rcvbuf_initial_size, 32 * 1024,
37 		"Receive buffer initial size in bytes.");
38 SDP_MODPARAM_SINT(rcvbuf_scale, 0x8,
39 		"Receive buffer size scale factor.");
40 
41 /* Like tcp_fin - called when SDP_MID_DISCONNECT is received */
42 static void
43 sdp_handle_disconn(struct sdp_sock *ssk)
44 {
45 
46 	sdp_dbg(ssk->socket, "%s\n", __func__);
47 
48 	SDP_WLOCK_ASSERT(ssk);
49 	if (TCPS_HAVERCVDFIN(ssk->state) == 0)
50 		socantrcvmore(ssk->socket);
51 
52 	switch (ssk->state) {
53 	case TCPS_SYN_RECEIVED:
54 	case TCPS_ESTABLISHED:
55 		ssk->state = TCPS_CLOSE_WAIT;
56 		break;
57 
58 	case TCPS_FIN_WAIT_1:
59 		/* Received a reply FIN - start Infiniband tear down */
60 		sdp_dbg(ssk->socket,
61 		    "%s: Starting Infiniband tear down sending DREQ\n",
62 		    __func__);
63 
64 		sdp_cancel_dreq_wait_timeout(ssk);
65 		ssk->qp_active = 0;
66 		if (ssk->id) {
67 			struct rdma_cm_id *id;
68 
69 			id = ssk->id;
70 			SDP_WUNLOCK(ssk);
71 			rdma_disconnect(id);
72 			SDP_WLOCK(ssk);
73 		} else {
74 			sdp_warn(ssk->socket,
75 			    "%s: ssk->id is NULL\n", __func__);
76 			return;
77 		}
78 		break;
79 	case TCPS_TIME_WAIT:
80 		/* This is a mutual close situation and we've got the DREQ from
81 		   the peer before the SDP_MID_DISCONNECT */
82 		break;
83 	case TCPS_CLOSED:
84 		/* FIN arrived after IB teardown started - do nothing */
85 		sdp_dbg(ssk->socket, "%s: fin in state %s\n",
86 		    __func__, sdp_state_str(ssk->state));
87 		return;
88 	default:
89 		sdp_warn(ssk->socket,
90 		    "%s: FIN in unexpected state. state=%d\n",
91 		    __func__, ssk->state);
92 		break;
93 	}
94 }
95 
96 static int
97 sdp_post_recv(struct sdp_sock *ssk)
98 {
99 	struct sdp_buf *rx_req;
100 	int i, rc;
101 	u64 addr;
102 	struct ib_device *dev;
103 	struct ib_recv_wr rx_wr = { NULL };
104 	struct ib_sge ibsge[SDP_MAX_RECV_SGES];
105 	struct ib_sge *sge = ibsge;
106 	const struct ib_recv_wr *bad_wr;
107 	struct mbuf *mb, *m;
108 	struct sdp_bsdh *h;
109 	int id = ring_head(ssk->rx_ring);
110 
111 	/* Now, allocate and repost recv */
112 	sdp_prf(ssk->socket, mb, "Posting mb");
113 	mb = m_getm2(NULL, ssk->recv_bytes, M_NOWAIT, MT_DATA, M_PKTHDR);
114 	if (mb == NULL) {
115 		/* Retry so we can't stall out with no memory. */
116 		if (!rx_ring_posted(ssk))
117 			queue_work(rx_comp_wq, &ssk->rx_comp_work);
118 		return -1;
119 	}
120 	for (m = mb; m != NULL; m = m->m_next) {
121 		m->m_len = M_SIZE(m);
122 		mb->m_pkthdr.len += m->m_len;
123 	}
124 	h = mtod(mb, struct sdp_bsdh *);
125 	rx_req = ssk->rx_ring.buffer + (id & (SDP_RX_SIZE - 1));
126 	rx_req->mb = mb;
127 	dev = ssk->ib_device;
128         for (i = 0;  mb != NULL; i++, mb = mb->m_next, sge++) {
129 		addr = ib_dma_map_single(dev, mb->m_data, mb->m_len,
130 		    DMA_TO_DEVICE);
131 		/* TODO: proper error handling */
132 		BUG_ON(ib_dma_mapping_error(dev, addr));
133 		BUG_ON(i >= SDP_MAX_RECV_SGES);
134 		rx_req->mapping[i] = addr;
135 		sge->addr = addr;
136 		sge->length = mb->m_len;
137 		sge->lkey = ssk->sdp_dev->pd->local_dma_lkey;
138         }
139 
140 	rx_wr.next = NULL;
141 	rx_wr.wr_id = id | SDP_OP_RECV;
142 	rx_wr.sg_list = ibsge;
143 	rx_wr.num_sge = i;
144 	rc = ib_post_recv(ssk->qp, &rx_wr, &bad_wr);
145 	if (unlikely(rc)) {
146 		sdp_warn(ssk->socket, "ib_post_recv failed. status %d\n", rc);
147 
148 		sdp_cleanup_sdp_buf(ssk, rx_req, DMA_FROM_DEVICE);
149 		m_freem(mb);
150 
151 		sdp_notify(ssk, ECONNRESET);
152 
153 		return -1;
154 	}
155 
156 	atomic_inc(&ssk->rx_ring.head);
157 	SDPSTATS_COUNTER_INC(post_recv);
158 
159 	return 0;
160 }
161 
162 static inline int
163 sdp_post_recvs_needed(struct sdp_sock *ssk)
164 {
165 	unsigned long bytes_in_process;
166 	unsigned long max_bytes;
167 	int buffer_size;
168 	int posted;
169 
170 	if (!ssk->qp_active || !ssk->socket)
171 		return 0;
172 
173 	posted = rx_ring_posted(ssk);
174 	if (posted >= SDP_RX_SIZE)
175 		return 0;
176 	if (posted < SDP_MIN_TX_CREDITS)
177 		return 1;
178 
179 	buffer_size = ssk->recv_bytes;
180 	max_bytes = max(ssk->socket->so_rcv.sb_hiwat,
181 	    (1 + SDP_MIN_TX_CREDITS) * buffer_size);
182 	max_bytes *= rcvbuf_scale;
183 	/*
184 	 * Compute bytes in the receive queue and socket buffer.
185 	 */
186 	bytes_in_process = (posted - SDP_MIN_TX_CREDITS) * buffer_size;
187 	bytes_in_process += sbused(&ssk->socket->so_rcv);
188 
189 	return bytes_in_process < max_bytes;
190 }
191 
192 static inline void
193 sdp_post_recvs(struct sdp_sock *ssk)
194 {
195 
196 	while (sdp_post_recvs_needed(ssk))
197 		if (sdp_post_recv(ssk))
198 			return;
199 }
200 
201 static inline struct mbuf *
202 sdp_sock_queue_rcv_mb(struct socket *sk, struct mbuf *mb)
203 {
204 	struct sdp_sock *ssk = sdp_sk(sk);
205 	struct sdp_bsdh *h;
206 
207 	h = mtod(mb, struct sdp_bsdh *);
208 
209 #ifdef SDP_ZCOPY
210 	SDP_SKB_CB(mb)->seq = rcv_nxt(ssk);
211 	if (h->mid == SDP_MID_SRCAVAIL) {
212 		struct sdp_srcah *srcah = (struct sdp_srcah *)(h+1);
213 		struct rx_srcavail_state *rx_sa;
214 
215 		ssk->srcavail_cancel_mseq = 0;
216 
217 		ssk->rx_sa = rx_sa = RX_SRCAVAIL_STATE(mb) = kzalloc(
218 				sizeof(struct rx_srcavail_state), M_NOWAIT);
219 
220 		rx_sa->mseq = ntohl(h->mseq);
221 		rx_sa->used = 0;
222 		rx_sa->len = mb_len = ntohl(srcah->len);
223 		rx_sa->rkey = ntohl(srcah->rkey);
224 		rx_sa->vaddr = be64_to_cpu(srcah->vaddr);
225 		rx_sa->flags = 0;
226 
227 		if (ssk->tx_sa) {
228 			sdp_dbg_data(ssk->socket, "got RX SrcAvail while waiting "
229 					"for TX SrcAvail. waking up TX SrcAvail"
230 					"to be aborted\n");
231 			wake_up(sk->sk_sleep);
232 		}
233 
234 		atomic_add(mb->len, &ssk->rcv_nxt);
235 		sdp_dbg_data(sk, "queueing SrcAvail. mb_len = %d vaddr = %lld\n",
236 			mb_len, rx_sa->vaddr);
237 	} else
238 #endif
239 	{
240 		atomic_add(mb->m_pkthdr.len, &ssk->rcv_nxt);
241 	}
242 
243 	m_adj(mb, SDP_HEAD_SIZE);
244 	SOCKBUF_LOCK(&sk->so_rcv);
245 	if (unlikely(h->flags & SDP_OOB_PRES))
246 		sdp_urg(ssk, mb);
247 	sbappend_locked(&sk->so_rcv, mb, 0);
248 	sorwakeup_locked(sk);
249 	return mb;
250 }
251 
252 static int
253 sdp_get_recv_bytes(struct sdp_sock *ssk, u32 new_size)
254 {
255 
256 	return MIN(new_size, SDP_MAX_PACKET);
257 }
258 
259 int
260 sdp_init_buffers(struct sdp_sock *ssk, u32 new_size)
261 {
262 
263 	ssk->recv_bytes = sdp_get_recv_bytes(ssk, new_size);
264 	sdp_post_recvs(ssk);
265 
266 	return 0;
267 }
268 
269 int
270 sdp_resize_buffers(struct sdp_sock *ssk, u32 new_size)
271 {
272 	u32 curr_size = ssk->recv_bytes;
273 	u32 max_size = SDP_MAX_PACKET;
274 
275 	if (new_size > curr_size && new_size <= max_size) {
276 		ssk->recv_bytes = sdp_get_recv_bytes(ssk, new_size);
277 		return 0;
278 	}
279 	return -1;
280 }
281 
282 static void
283 sdp_handle_resize_request(struct sdp_sock *ssk, struct sdp_chrecvbuf *buf)
284 {
285 	if (sdp_resize_buffers(ssk, ntohl(buf->size)) == 0)
286 		ssk->recv_request_head = ring_head(ssk->rx_ring) + 1;
287 	else
288 		ssk->recv_request_head = ring_tail(ssk->rx_ring);
289 	ssk->recv_request = 1;
290 }
291 
292 static void
293 sdp_handle_resize_ack(struct sdp_sock *ssk, struct sdp_chrecvbuf *buf)
294 {
295 	u32 new_size = ntohl(buf->size);
296 
297 	if (new_size > ssk->xmit_size_goal)
298 		ssk->xmit_size_goal = new_size;
299 }
300 
301 static struct mbuf *
302 sdp_recv_completion(struct sdp_sock *ssk, int id)
303 {
304 	struct sdp_buf *rx_req;
305 	struct ib_device *dev;
306 	struct mbuf *mb;
307 
308 	if (unlikely(id != ring_tail(ssk->rx_ring))) {
309 		printk(KERN_WARNING "Bogus recv completion id %d tail %d\n",
310 			id, ring_tail(ssk->rx_ring));
311 		return NULL;
312 	}
313 
314 	dev = ssk->ib_device;
315 	rx_req = &ssk->rx_ring.buffer[id & (SDP_RX_SIZE - 1)];
316 	mb = rx_req->mb;
317 	sdp_cleanup_sdp_buf(ssk, rx_req, DMA_FROM_DEVICE);
318 
319 	atomic_inc(&ssk->rx_ring.tail);
320 	atomic_dec(&ssk->remote_credits);
321 	return mb;
322 }
323 
324 static void
325 sdp_process_rx_ctl_mb(struct sdp_sock *ssk, struct mbuf *mb)
326 {
327 	struct sdp_bsdh *h;
328 	struct socket *sk;
329 
330 	SDP_WLOCK_ASSERT(ssk);
331 
332 	sk = ssk->socket;
333  	h = mtod(mb, struct sdp_bsdh *);
334 	switch (h->mid) {
335 	case SDP_MID_DATA:
336 	case SDP_MID_SRCAVAIL:
337 		sdp_dbg(sk, "DATA after socket rcv was shutdown\n");
338 
339 		/* got data in RCV_SHUTDOWN */
340 		if (ssk->state == TCPS_FIN_WAIT_1) {
341 			sdp_dbg(sk, "RX data when state = FIN_WAIT1\n");
342 			sdp_notify(ssk, ECONNRESET);
343 		}
344 
345 		break;
346 #ifdef SDP_ZCOPY
347 	case SDP_MID_RDMARDCOMPL:
348 		break;
349 	case SDP_MID_SENDSM:
350 		sdp_handle_sendsm(ssk, ntohl(h->mseq_ack));
351 		break;
352 	case SDP_MID_SRCAVAIL_CANCEL:
353 		sdp_dbg_data(sk, "Handling SrcAvailCancel\n");
354 		sdp_prf(sk, NULL, "Handling SrcAvailCancel");
355 		if (ssk->rx_sa) {
356 			ssk->srcavail_cancel_mseq = ntohl(h->mseq);
357 			ssk->rx_sa->flags |= RX_SA_ABORTED;
358 			ssk->rx_sa = NULL; /* TODO: change it into SDP_MID_DATA and get
359 			                      the dirty logic from recvmsg */
360 		} else {
361 			sdp_dbg(sk, "Got SrcAvailCancel - "
362 					"but no SrcAvail in process\n");
363 		}
364 		break;
365 	case SDP_MID_SINKAVAIL:
366 		sdp_dbg_data(sk, "Got SinkAvail - not supported: ignored\n");
367 		sdp_prf(sk, NULL, "Got SinkAvail - not supported: ignored");
368 		/* FALLTHROUGH */
369 #endif
370 	case SDP_MID_ABORT:
371 		sdp_dbg_data(sk, "Handling ABORT\n");
372 		sdp_prf(sk, NULL, "Handling ABORT");
373 		sdp_notify(ssk, ECONNRESET);
374 		break;
375 	case SDP_MID_DISCONN:
376 		sdp_dbg_data(sk, "Handling DISCONN\n");
377 		sdp_prf(sk, NULL, "Handling DISCONN");
378 		sdp_handle_disconn(ssk);
379 		break;
380 	case SDP_MID_CHRCVBUF:
381 		sdp_dbg_data(sk, "Handling RX CHRCVBUF\n");
382 		sdp_handle_resize_request(ssk, (struct sdp_chrecvbuf *)(h+1));
383 		break;
384 	case SDP_MID_CHRCVBUF_ACK:
385 		sdp_dbg_data(sk, "Handling RX CHRCVBUF_ACK\n");
386 		sdp_handle_resize_ack(ssk, (struct sdp_chrecvbuf *)(h+1));
387 		break;
388 	default:
389 		/* TODO: Handle other messages */
390 		sdp_warn(sk, "SDP: FIXME MID %d\n", h->mid);
391 		break;
392 	}
393 	m_freem(mb);
394 }
395 
396 static int
397 sdp_process_rx_mb(struct sdp_sock *ssk, struct mbuf *mb)
398 {
399 	struct socket *sk;
400 	struct sdp_bsdh *h;
401 	unsigned long mseq_ack;
402 	int credits_before;
403 
404 	h = mtod(mb, struct sdp_bsdh *);
405 	sk = ssk->socket;
406 	/*
407 	 * If another thread is in so_pcbfree this may be partially torn
408 	 * down but no further synchronization is required as the destroying
409 	 * thread will wait for receive to shutdown before discarding the
410 	 * socket.
411 	 */
412 	if (sk == NULL) {
413 		m_freem(mb);
414 		return 0;
415 	}
416 
417 	SDPSTATS_HIST_LINEAR(credits_before_update, tx_credits(ssk));
418 
419 	mseq_ack = ntohl(h->mseq_ack);
420 	credits_before = tx_credits(ssk);
421 	atomic_set(&ssk->tx_ring.credits, mseq_ack - ring_head(ssk->tx_ring) +
422 			1 + ntohs(h->bufs));
423 	if (mseq_ack >= ssk->nagle_last_unacked)
424 		ssk->nagle_last_unacked = 0;
425 
426 	sdp_prf1(ssk->socket, mb, "RX %s +%d c:%d->%d mseq:%d ack:%d\n",
427 		mid2str(h->mid), ntohs(h->bufs), credits_before,
428 		tx_credits(ssk), ntohl(h->mseq), ntohl(h->mseq_ack));
429 
430 	if (unlikely(h->mid == SDP_MID_DATA &&
431 	    mb->m_pkthdr.len == SDP_HEAD_SIZE)) {
432 		/* Credit update is valid even after RCV_SHUTDOWN */
433 		m_freem(mb);
434 		return 0;
435 	}
436 
437 	if ((h->mid != SDP_MID_DATA && h->mid != SDP_MID_SRCAVAIL) ||
438 	    TCPS_HAVERCVDFIN(ssk->state)) {
439 		sdp_prf(sk, NULL, "Control mb - queing to control queue");
440 #ifdef SDP_ZCOPY
441 		if (h->mid == SDP_MID_SRCAVAIL_CANCEL) {
442 			sdp_dbg_data(sk, "Got SrcAvailCancel. "
443 					"seq: 0x%d seq_ack: 0x%d\n",
444 					ntohl(h->mseq), ntohl(h->mseq_ack));
445 			ssk->srcavail_cancel_mseq = ntohl(h->mseq);
446 		}
447 
448 
449 		if (h->mid == SDP_MID_RDMARDCOMPL) {
450 			struct sdp_rrch *rrch = (struct sdp_rrch *)(h+1);
451 			sdp_dbg_data(sk, "RdmaRdCompl message arrived\n");
452 			sdp_handle_rdma_read_compl(ssk, ntohl(h->mseq_ack),
453 					ntohl(rrch->len));
454 		}
455 #endif
456 		if (mbufq_enqueue(&ssk->rxctlq, mb) != 0)
457 			m_freem(mb);
458 		return (0);
459 	}
460 
461 	sdp_prf1(sk, NULL, "queueing %s mb\n", mid2str(h->mid));
462 	mb = sdp_sock_queue_rcv_mb(sk, mb);
463 
464 
465 	return 0;
466 }
467 
468 /* called only from irq */
469 static struct mbuf *
470 sdp_process_rx_wc(struct sdp_sock *ssk, struct ib_wc *wc)
471 {
472 	struct mbuf *mb;
473 	struct sdp_bsdh *h;
474 	struct socket *sk = ssk->socket;
475 	int mseq;
476 
477 	mb = sdp_recv_completion(ssk, wc->wr_id);
478 	if (unlikely(!mb))
479 		return NULL;
480 
481 	if (unlikely(wc->status)) {
482 		if (ssk->qp_active && sk) {
483 			sdp_dbg(sk, "Recv completion with error. "
484 			    "Status %s (%d), vendor: %d\n",
485 			    ib_wc_status_msg(wc->status), wc->status,
486 			    wc->vendor_err);
487 			sdp_abort(sk);
488 			ssk->qp_active = 0;
489 		}
490 		m_freem(mb);
491 		return NULL;
492 	}
493 
494 	sdp_dbg_data(sk, "Recv completion. ID %d Length %d\n",
495 			(int)wc->wr_id, wc->byte_len);
496 	if (unlikely(wc->byte_len < sizeof(struct sdp_bsdh))) {
497 		sdp_warn(sk, "SDP BUG! byte_len %d < %zd\n",
498 				wc->byte_len, sizeof(struct sdp_bsdh));
499 		m_freem(mb);
500 		return NULL;
501 	}
502 	/* Use m_adj to trim the tail of data we didn't use. */
503 	m_adj(mb, -(mb->m_pkthdr.len - wc->byte_len));
504 	h = mtod(mb, struct sdp_bsdh *);
505 
506 	SDP_DUMP_PACKET(ssk->socket, "RX", mb, h);
507 
508 	ssk->rx_packets++;
509 	ssk->rx_bytes += mb->m_pkthdr.len;
510 
511 	mseq = ntohl(h->mseq);
512 	atomic_set(&ssk->mseq_ack, mseq);
513 	if (mseq != (int)wc->wr_id)
514 		sdp_warn(sk, "SDP BUG! mseq %d != wrid %d\n",
515 				mseq, (int)wc->wr_id);
516 
517 	return mb;
518 }
519 
520 /* Wakeup writers if we now have credits. */
521 static void
522 sdp_bzcopy_write_space(struct sdp_sock *ssk)
523 {
524 	struct socket *sk = ssk->socket;
525 
526 	if (tx_credits(ssk) >= ssk->min_bufs && sk)
527 		sowwakeup(sk);
528 }
529 
530 /* only from interrupt. */
531 static int
532 sdp_poll_rx_cq(struct sdp_sock *ssk)
533 {
534 	struct ib_cq *cq = ssk->rx_ring.cq;
535 	struct ib_wc ibwc[SDP_NUM_WC];
536 	int n, i;
537 	int wc_processed = 0;
538 	struct mbuf *mb;
539 
540 	do {
541 		n = ib_poll_cq(cq, SDP_NUM_WC, ibwc);
542 		for (i = 0; i < n; ++i) {
543 			struct ib_wc *wc = &ibwc[i];
544 
545 			BUG_ON(!(wc->wr_id & SDP_OP_RECV));
546 			mb = sdp_process_rx_wc(ssk, wc);
547 			if (!mb)
548 				continue;
549 
550 			sdp_process_rx_mb(ssk, mb);
551 			wc_processed++;
552 		}
553 	} while (n == SDP_NUM_WC);
554 
555 	if (wc_processed)
556 		sdp_bzcopy_write_space(ssk);
557 
558 	return wc_processed;
559 }
560 
561 static void
562 sdp_rx_comp_work(struct work_struct *work)
563 {
564 	struct sdp_sock *ssk = container_of(work, struct sdp_sock,
565 			rx_comp_work);
566 
567 	sdp_prf(ssk->socket, NULL, "%s", __func__);
568 
569 	SDP_WLOCK(ssk);
570 	if (unlikely(!ssk->qp)) {
571 		sdp_prf(ssk->socket, NULL, "qp was destroyed");
572 		goto out;
573 	}
574 	if (unlikely(!ssk->rx_ring.cq)) {
575 		sdp_prf(ssk->socket, NULL, "rx_ring.cq is NULL");
576 		goto out;
577 	}
578 
579 	if (unlikely(!ssk->poll_cq)) {
580 		struct rdma_cm_id *id = ssk->id;
581 		if (id && id->qp)
582 			rdma_notify(id, IB_EVENT_COMM_EST);
583 		goto out;
584 	}
585 
586 	sdp_do_posts(ssk);
587 out:
588 	SDP_WUNLOCK(ssk);
589 }
590 
591 void
592 sdp_do_posts(struct sdp_sock *ssk)
593 {
594 	struct socket *sk = ssk->socket;
595 	int xmit_poll_force;
596 	struct mbuf *mb;
597 
598 	SDP_WLOCK_ASSERT(ssk);
599 	if (!ssk->qp_active) {
600 		sdp_dbg(sk, "QP is deactivated\n");
601 		return;
602 	}
603 
604 	while ((mb = mbufq_dequeue(&ssk->rxctlq)) != NULL)
605 		sdp_process_rx_ctl_mb(ssk, mb);
606 
607 	if (ssk->state == TCPS_TIME_WAIT)
608 		return;
609 
610 	if (!ssk->rx_ring.cq || !ssk->tx_ring.cq)
611 		return;
612 
613 	sdp_post_recvs(ssk);
614 
615 	if (tx_ring_posted(ssk))
616 		sdp_xmit_poll(ssk, 1);
617 
618 	sdp_post_sends(ssk, M_NOWAIT);
619 
620 	xmit_poll_force = tx_credits(ssk) < SDP_MIN_TX_CREDITS;
621 
622 	if (credit_update_needed(ssk) || xmit_poll_force) {
623 		/* if has pending tx because run out of tx_credits - xmit it */
624 		sdp_prf(sk, NULL, "Processing to free pending sends");
625 		sdp_xmit_poll(ssk,  xmit_poll_force);
626 		sdp_prf(sk, NULL, "Sending credit update");
627 		sdp_post_sends(ssk, M_NOWAIT);
628 	}
629 
630 }
631 
632 int
633 sdp_process_rx(struct sdp_sock *ssk)
634 {
635 	int wc_processed = 0;
636 	int credits_before;
637 
638 	if (!rx_ring_trylock(&ssk->rx_ring)) {
639 		sdp_dbg(ssk->socket, "ring destroyed. not polling it\n");
640 		return 0;
641 	}
642 
643 	credits_before = tx_credits(ssk);
644 
645 	wc_processed = sdp_poll_rx_cq(ssk);
646 	sdp_prf(ssk->socket, NULL, "processed %d", wc_processed);
647 
648 	if (wc_processed) {
649 		sdp_prf(ssk->socket, NULL, "credits:  %d -> %d",
650 				credits_before, tx_credits(ssk));
651 		queue_work(rx_comp_wq, &ssk->rx_comp_work);
652 	}
653 	sdp_arm_rx_cq(ssk);
654 
655 	rx_ring_unlock(&ssk->rx_ring);
656 
657 	return (wc_processed);
658 }
659 
660 static void
661 sdp_rx_irq(struct ib_cq *cq, void *cq_context)
662 {
663 	struct sdp_sock *ssk;
664 
665 	ssk = cq_context;
666 	KASSERT(cq == ssk->rx_ring.cq,
667 	    ("%s: mismatched cq on %p", __func__, ssk));
668 
669 	SDPSTATS_COUNTER_INC(rx_int_count);
670 
671 	sdp_prf(sk, NULL, "rx irq");
672 
673 	sdp_process_rx(ssk);
674 }
675 
676 static
677 void sdp_rx_ring_purge(struct sdp_sock *ssk)
678 {
679 	while (rx_ring_posted(ssk) > 0) {
680 		struct mbuf *mb;
681 		mb = sdp_recv_completion(ssk, ring_tail(ssk->rx_ring));
682 		if (!mb)
683 			break;
684 		m_freem(mb);
685 	}
686 }
687 
688 void
689 sdp_rx_ring_init(struct sdp_sock *ssk)
690 {
691 	ssk->rx_ring.buffer = NULL;
692 	ssk->rx_ring.destroyed = 0;
693 	rw_init(&ssk->rx_ring.destroyed_lock, "sdp rx lock");
694 }
695 
696 static void
697 sdp_rx_cq_event_handler(struct ib_event *event, void *data)
698 {
699 }
700 
701 int
702 sdp_rx_ring_create(struct sdp_sock *ssk, struct ib_device *device)
703 {
704 	struct ib_cq_init_attr rx_cq_attr = {
705 		.cqe = SDP_RX_SIZE,
706 		.comp_vector = 0,
707 		.flags = 0,
708 	};
709 	struct ib_cq *rx_cq;
710 	int rc = 0;
711 
712 	sdp_dbg(ssk->socket, "rx ring created");
713 	INIT_WORK(&ssk->rx_comp_work, sdp_rx_comp_work);
714 	atomic_set(&ssk->rx_ring.head, 1);
715 	atomic_set(&ssk->rx_ring.tail, 1);
716 
717 	ssk->rx_ring.buffer = malloc(sizeof(*ssk->rx_ring.buffer) * SDP_RX_SIZE,
718 	    M_SDP, M_WAITOK);
719 
720 	rx_cq = ib_create_cq(device, sdp_rx_irq, sdp_rx_cq_event_handler,
721 	    ssk, &rx_cq_attr);
722 	if (IS_ERR(rx_cq)) {
723 		rc = PTR_ERR(rx_cq);
724 		sdp_warn(ssk->socket, "Unable to allocate RX CQ: %d.\n", rc);
725 		goto err_cq;
726 	}
727 
728 	sdp_sk(ssk->socket)->rx_ring.cq = rx_cq;
729 	sdp_arm_rx_cq(ssk);
730 
731 	return 0;
732 
733 err_cq:
734 	free(ssk->rx_ring.buffer, M_SDP);
735 	ssk->rx_ring.buffer = NULL;
736 	return rc;
737 }
738 
739 void
740 sdp_rx_ring_destroy(struct sdp_sock *ssk)
741 {
742 
743 	cancel_work_sync(&ssk->rx_comp_work);
744 	rx_ring_destroy_lock(&ssk->rx_ring);
745 
746 	if (ssk->rx_ring.buffer) {
747 		sdp_rx_ring_purge(ssk);
748 		free(ssk->rx_ring.buffer, M_SDP);
749 		ssk->rx_ring.buffer = NULL;
750 	}
751 
752 	if (ssk->rx_ring.cq) {
753 		ib_destroy_cq(ssk->rx_ring.cq);
754 		ssk->rx_ring.cq = NULL;
755 	}
756 
757 	WARN_ON(ring_head(ssk->rx_ring) != ring_tail(ssk->rx_ring));
758 }
759