1/*
2 * Copyright(c) 2015 - 2018 Intel Corporation.
3 *
4 * This file is provided under a dual BSD/GPLv2 license.  When using or
5 * redistributing this file, you may do so under either license.
6 *
7 * GPL LICENSE SUMMARY
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of version 2 of the GNU General Public License as
11 * published by the Free Software Foundation.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16 * General Public License for more details.
17 *
18 * BSD LICENSE
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
23 *
24 *  - Redistributions of source code must retain the above copyright
25 *    notice, this list of conditions and the following disclaimer.
26 *  - Redistributions in binary form must reproduce the above copyright
27 *    notice, this list of conditions and the following disclaimer in
28 *    the documentation and/or other materials provided with the
29 *    distribution.
30 *  - Neither the name of Intel Corporation nor the names of its
31 *    contributors may be used to endorse or promote products derived
32 *    from this software without specific prior written permission.
33 *
34 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
35 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
36 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
37 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
38 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
39 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
40 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
41 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
42 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
43 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
44 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 *
46 */
47
48#include <linux/io.h>
49#include <rdma/rdma_vt.h>
50#include <rdma/rdmavt_qp.h>
51
52#include "hfi.h"
53#include "qp.h"
54#include "rc.h"
55#include "verbs_txreq.h"
56#include "trace.h"
57
58struct rvt_ack_entry *find_prev_entry(struct rvt_qp *qp, u32 psn, u8 *prev,
59				      u8 *prev_ack, bool *scheduled)
60	__must_hold(&qp->s_lock)
61{
62	struct rvt_ack_entry *e = NULL;
63	u8 i, p;
64	bool s = true;
65
66	for (i = qp->r_head_ack_queue; ; i = p) {
67		if (i == qp->s_tail_ack_queue)
68			s = false;
69		if (i)
70			p = i - 1;
71		else
72			p = rvt_size_atomic(ib_to_rvt(qp->ibqp.device));
73		if (p == qp->r_head_ack_queue) {
74			e = NULL;
75			break;
76		}
77		e = &qp->s_ack_queue[p];
78		if (!e->opcode) {
79			e = NULL;
80			break;
81		}
82		if (cmp_psn(psn, e->psn) >= 0) {
83			if (p == qp->s_tail_ack_queue &&
84			    cmp_psn(psn, e->lpsn) <= 0)
85				s = false;
86			break;
87		}
88	}
89	if (prev)
90		*prev = p;
91	if (prev_ack)
92		*prev_ack = i;
93	if (scheduled)
94		*scheduled = s;
95	return e;
96}
97
98/**
99 * make_rc_ack - construct a response packet (ACK, NAK, or RDMA read)
100 * @dev: the device for this QP
101 * @qp: a pointer to the QP
102 * @ohdr: a pointer to the IB header being constructed
103 * @ps: the xmit packet state
104 *
105 * Return 1 if constructed; otherwise, return 0.
106 * Note that we are in the responder's side of the QP context.
107 * Note the QP s_lock must be held.
108 */
109static int make_rc_ack(struct hfi1_ibdev *dev, struct rvt_qp *qp,
110		       struct ib_other_headers *ohdr,
111		       struct hfi1_pkt_state *ps)
112{
113	struct rvt_ack_entry *e;
114	u32 hwords, hdrlen;
115	u32 len = 0;
116	u32 bth0 = 0, bth2 = 0;
117	u32 bth1 = qp->remote_qpn | (HFI1_CAP_IS_KSET(OPFN) << IB_BTHE_E_SHIFT);
118	int middle = 0;
119	u32 pmtu = qp->pmtu;
120	struct hfi1_qp_priv *qpriv = qp->priv;
121	bool last_pkt;
122	u32 delta;
123	u8 next = qp->s_tail_ack_queue;
124	struct tid_rdma_request *req;
125
126	trace_hfi1_rsp_make_rc_ack(qp, 0);
127	lockdep_assert_held(&qp->s_lock);
128	/* Don't send an ACK if we aren't supposed to. */
129	if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
130		goto bail;
131
132	if (qpriv->hdr_type == HFI1_PKT_TYPE_9B)
133		/* header size in 32-bit words LRH+BTH = (8+12)/4. */
134		hwords = 5;
135	else
136		/* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
137		hwords = 7;
138
139	switch (qp->s_ack_state) {
140	case OP(RDMA_READ_RESPONSE_LAST):
141	case OP(RDMA_READ_RESPONSE_ONLY):
142		e = &qp->s_ack_queue[qp->s_tail_ack_queue];
143		release_rdma_sge_mr(e);
144		fallthrough;
145	case OP(ATOMIC_ACKNOWLEDGE):
146		/*
147		 * We can increment the tail pointer now that the last
148		 * response has been sent instead of only being
149		 * constructed.
150		 */
151		if (++next > rvt_size_atomic(&dev->rdi))
152			next = 0;
153		/*
154		 * Only advance the s_acked_ack_queue pointer if there
155		 * have been no TID RDMA requests.
156		 */
157		e = &qp->s_ack_queue[qp->s_tail_ack_queue];
158		if (e->opcode != TID_OP(WRITE_REQ) &&
159		    qp->s_acked_ack_queue == qp->s_tail_ack_queue)
160			qp->s_acked_ack_queue = next;
161		qp->s_tail_ack_queue = next;
162		trace_hfi1_rsp_make_rc_ack(qp, e->psn);
163		fallthrough;
164	case OP(SEND_ONLY):
165	case OP(ACKNOWLEDGE):
166		/* Check for no next entry in the queue. */
167		if (qp->r_head_ack_queue == qp->s_tail_ack_queue) {
168			if (qp->s_flags & RVT_S_ACK_PENDING)
169				goto normal;
170			goto bail;
171		}
172
173		e = &qp->s_ack_queue[qp->s_tail_ack_queue];
174		/* Check for tid write fence */
175		if ((qpriv->s_flags & HFI1_R_TID_WAIT_INTERLCK) ||
176		    hfi1_tid_rdma_ack_interlock(qp, e)) {
177			iowait_set_flag(&qpriv->s_iowait, IOWAIT_PENDING_IB);
178			goto bail;
179		}
180		if (e->opcode == OP(RDMA_READ_REQUEST)) {
181			/*
182			 * If a RDMA read response is being resent and
183			 * we haven't seen the duplicate request yet,
184			 * then stop sending the remaining responses the
185			 * responder has seen until the requester re-sends it.
186			 */
187			len = e->rdma_sge.sge_length;
188			if (len && !e->rdma_sge.mr) {
189				if (qp->s_acked_ack_queue ==
190				    qp->s_tail_ack_queue)
191					qp->s_acked_ack_queue =
192						qp->r_head_ack_queue;
193				qp->s_tail_ack_queue = qp->r_head_ack_queue;
194				goto bail;
195			}
196			/* Copy SGE state in case we need to resend */
197			ps->s_txreq->mr = e->rdma_sge.mr;
198			if (ps->s_txreq->mr)
199				rvt_get_mr(ps->s_txreq->mr);
200			qp->s_ack_rdma_sge.sge = e->rdma_sge;
201			qp->s_ack_rdma_sge.num_sge = 1;
202			ps->s_txreq->ss = &qp->s_ack_rdma_sge;
203			if (len > pmtu) {
204				len = pmtu;
205				qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST);
206			} else {
207				qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY);
208				e->sent = 1;
209			}
210			ohdr->u.aeth = rvt_compute_aeth(qp);
211			hwords++;
212			qp->s_ack_rdma_psn = e->psn;
213			bth2 = mask_psn(qp->s_ack_rdma_psn++);
214		} else if (e->opcode == TID_OP(WRITE_REQ)) {
215			/*
216			 * If a TID RDMA WRITE RESP is being resent, we have to
217			 * wait for the actual request. All requests that are to
218			 * be resent will have their state set to
219			 * TID_REQUEST_RESEND. When the new request arrives, the
220			 * state will be changed to TID_REQUEST_RESEND_ACTIVE.
221			 */
222			req = ack_to_tid_req(e);
223			if (req->state == TID_REQUEST_RESEND ||
224			    req->state == TID_REQUEST_INIT_RESEND)
225				goto bail;
226			qp->s_ack_state = TID_OP(WRITE_RESP);
227			qp->s_ack_rdma_psn = mask_psn(e->psn + req->cur_seg);
228			goto write_resp;
229		} else if (e->opcode == TID_OP(READ_REQ)) {
230			/*
231			 * If a TID RDMA read response is being resent and
232			 * we haven't seen the duplicate request yet,
233			 * then stop sending the remaining responses the
234			 * responder has seen until the requester re-sends it.
235			 */
236			len = e->rdma_sge.sge_length;
237			if (len && !e->rdma_sge.mr) {
238				if (qp->s_acked_ack_queue ==
239				    qp->s_tail_ack_queue)
240					qp->s_acked_ack_queue =
241						qp->r_head_ack_queue;
242				qp->s_tail_ack_queue = qp->r_head_ack_queue;
243				goto bail;
244			}
245			/* Copy SGE state in case we need to resend */
246			ps->s_txreq->mr = e->rdma_sge.mr;
247			if (ps->s_txreq->mr)
248				rvt_get_mr(ps->s_txreq->mr);
249			qp->s_ack_rdma_sge.sge = e->rdma_sge;
250			qp->s_ack_rdma_sge.num_sge = 1;
251			qp->s_ack_state = TID_OP(READ_RESP);
252			goto read_resp;
253		} else {
254			/* COMPARE_SWAP or FETCH_ADD */
255			ps->s_txreq->ss = NULL;
256			len = 0;
257			qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
258			ohdr->u.at.aeth = rvt_compute_aeth(qp);
259			ib_u64_put(e->atomic_data, &ohdr->u.at.atomic_ack_eth);
260			hwords += sizeof(ohdr->u.at) / sizeof(u32);
261			bth2 = mask_psn(e->psn);
262			e->sent = 1;
263		}
264		trace_hfi1_tid_write_rsp_make_rc_ack(qp);
265		bth0 = qp->s_ack_state << 24;
266		break;
267
268	case OP(RDMA_READ_RESPONSE_FIRST):
269		qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE);
270		fallthrough;
271	case OP(RDMA_READ_RESPONSE_MIDDLE):
272		ps->s_txreq->ss = &qp->s_ack_rdma_sge;
273		ps->s_txreq->mr = qp->s_ack_rdma_sge.sge.mr;
274		if (ps->s_txreq->mr)
275			rvt_get_mr(ps->s_txreq->mr);
276		len = qp->s_ack_rdma_sge.sge.sge_length;
277		if (len > pmtu) {
278			len = pmtu;
279			middle = HFI1_CAP_IS_KSET(SDMA_AHG);
280		} else {
281			ohdr->u.aeth = rvt_compute_aeth(qp);
282			hwords++;
283			qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
284			e = &qp->s_ack_queue[qp->s_tail_ack_queue];
285			e->sent = 1;
286		}
287		bth0 = qp->s_ack_state << 24;
288		bth2 = mask_psn(qp->s_ack_rdma_psn++);
289		break;
290
291	case TID_OP(WRITE_RESP):
292write_resp:
293		/*
294		 * 1. Check if RVT_S_ACK_PENDING is set. If yes,
295		 *    goto normal.
296		 * 2. Attempt to allocate TID resources.
297		 * 3. Remove RVT_S_RESP_PENDING flags from s_flags
298		 * 4. If resources not available:
299		 *    4.1 Set RVT_S_WAIT_TID_SPACE
300		 *    4.2 Queue QP on RCD TID queue
301		 *    4.3 Put QP on iowait list.
302		 *    4.4 Build IB RNR NAK with appropriate timeout value
303		 *    4.5 Return indication progress made.
304		 * 5. If resources are available:
305		 *    5.1 Program HW flow CSRs
306		 *    5.2 Build TID RDMA WRITE RESP packet
307		 *    5.3 If more resources needed, do 2.1 - 2.3.
308		 *    5.4 Wake up next QP on RCD TID queue.
309		 *    5.5 Return indication progress made.
310		 */
311
312		e = &qp->s_ack_queue[qp->s_tail_ack_queue];
313		req = ack_to_tid_req(e);
314
315		/*
316		 * Send scheduled RNR NAK's. RNR NAK's need to be sent at
317		 * segment boundaries, not at request boundaries. Don't change
318		 * s_ack_state because we are still in the middle of a request
319		 */
320		if (qpriv->rnr_nak_state == TID_RNR_NAK_SEND &&
321		    qp->s_tail_ack_queue == qpriv->r_tid_alloc &&
322		    req->cur_seg == req->alloc_seg) {
323			qpriv->rnr_nak_state = TID_RNR_NAK_SENT;
324			goto normal_no_state;
325		}
326
327		bth2 = mask_psn(qp->s_ack_rdma_psn);
328		hdrlen = hfi1_build_tid_rdma_write_resp(qp, e, ohdr, &bth1,
329							bth2, &len,
330							&ps->s_txreq->ss);
331		if (!hdrlen)
332			return 0;
333
334		hwords += hdrlen;
335		bth0 = qp->s_ack_state << 24;
336		qp->s_ack_rdma_psn++;
337		trace_hfi1_tid_req_make_rc_ack_write(qp, 0, e->opcode, e->psn,
338						     e->lpsn, req);
339		if (req->cur_seg != req->total_segs)
340			break;
341
342		e->sent = 1;
343		/* Do not free e->rdma_sge until all data are received */
344		qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE);
345		break;
346
347	case TID_OP(READ_RESP):
348read_resp:
349		e = &qp->s_ack_queue[qp->s_tail_ack_queue];
350		ps->s_txreq->ss = &qp->s_ack_rdma_sge;
351		delta = hfi1_build_tid_rdma_read_resp(qp, e, ohdr, &bth0,
352						      &bth1, &bth2, &len,
353						      &last_pkt);
354		if (delta == 0)
355			goto error_qp;
356		hwords += delta;
357		if (last_pkt) {
358			e->sent = 1;
359			/*
360			 * Increment qp->s_tail_ack_queue through s_ack_state
361			 * transition.
362			 */
363			qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST);
364		}
365		break;
366	case TID_OP(READ_REQ):
367		goto bail;
368
369	default:
370normal:
371		/*
372		 * Send a regular ACK.
373		 * Set the s_ack_state so we wait until after sending
374		 * the ACK before setting s_ack_state to ACKNOWLEDGE
375		 * (see above).
376		 */
377		qp->s_ack_state = OP(SEND_ONLY);
378normal_no_state:
379		if (qp->s_nak_state)
380			ohdr->u.aeth =
381				cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
382					    (qp->s_nak_state <<
383					     IB_AETH_CREDIT_SHIFT));
384		else
385			ohdr->u.aeth = rvt_compute_aeth(qp);
386		hwords++;
387		len = 0;
388		bth0 = OP(ACKNOWLEDGE) << 24;
389		bth2 = mask_psn(qp->s_ack_psn);
390		qp->s_flags &= ~RVT_S_ACK_PENDING;
391		ps->s_txreq->txreq.flags |= SDMA_TXREQ_F_VIP;
392		ps->s_txreq->ss = NULL;
393	}
394	qp->s_rdma_ack_cnt++;
395	ps->s_txreq->sde = qpriv->s_sde;
396	ps->s_txreq->s_cur_size = len;
397	ps->s_txreq->hdr_dwords = hwords;
398	hfi1_make_ruc_header(qp, ohdr, bth0, bth1, bth2, middle, ps);
399	return 1;
400error_qp:
401	spin_unlock_irqrestore(&qp->s_lock, ps->flags);
402	spin_lock_irqsave(&qp->r_lock, ps->flags);
403	spin_lock(&qp->s_lock);
404	rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
405	spin_unlock(&qp->s_lock);
406	spin_unlock_irqrestore(&qp->r_lock, ps->flags);
407	spin_lock_irqsave(&qp->s_lock, ps->flags);
408bail:
409	qp->s_ack_state = OP(ACKNOWLEDGE);
410	/*
411	 * Ensure s_rdma_ack_cnt changes are committed prior to resetting
412	 * RVT_S_RESP_PENDING
413	 */
414	smp_wmb();
415	qp->s_flags &= ~(RVT_S_RESP_PENDING
416				| RVT_S_ACK_PENDING
417				| HFI1_S_AHG_VALID);
418	return 0;
419}
420
421/**
422 * hfi1_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC)
423 * @qp: a pointer to the QP
424 *
425 * Assumes s_lock is held.
426 *
427 * Return 1 if constructed; otherwise, return 0.
428 */
429int hfi1_make_rc_req(struct rvt_qp *qp, struct hfi1_pkt_state *ps)
430{
431	struct hfi1_qp_priv *priv = qp->priv;
432	struct hfi1_ibdev *dev = to_idev(qp->ibqp.device);
433	struct ib_other_headers *ohdr;
434	struct rvt_sge_state *ss = NULL;
435	struct rvt_swqe *wqe;
436	struct hfi1_swqe_priv *wpriv;
437	struct tid_rdma_request *req = NULL;
438	/* header size in 32-bit words LRH+BTH = (8+12)/4. */
439	u32 hwords = 5;
440	u32 len = 0;
441	u32 bth0 = 0, bth2 = 0;
442	u32 bth1 = qp->remote_qpn | (HFI1_CAP_IS_KSET(OPFN) << IB_BTHE_E_SHIFT);
443	u32 pmtu = qp->pmtu;
444	char newreq;
445	int middle = 0;
446	int delta;
447	struct tid_rdma_flow *flow = NULL;
448	struct tid_rdma_params *remote;
449
450	trace_hfi1_sender_make_rc_req(qp);
451	lockdep_assert_held(&qp->s_lock);
452	ps->s_txreq = get_txreq(ps->dev, qp);
453	if (!ps->s_txreq)
454		goto bail_no_tx;
455
456	if (priv->hdr_type == HFI1_PKT_TYPE_9B) {
457		/* header size in 32-bit words LRH+BTH = (8+12)/4. */
458		hwords = 5;
459		if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)
460			ohdr = &ps->s_txreq->phdr.hdr.ibh.u.l.oth;
461		else
462			ohdr = &ps->s_txreq->phdr.hdr.ibh.u.oth;
463	} else {
464		/* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
465		hwords = 7;
466		if ((rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
467		    (hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))))
468			ohdr = &ps->s_txreq->phdr.hdr.opah.u.l.oth;
469		else
470			ohdr = &ps->s_txreq->phdr.hdr.opah.u.oth;
471	}
472
473	/* Sending responses has higher priority over sending requests. */
474	if ((qp->s_flags & RVT_S_RESP_PENDING) &&
475	    make_rc_ack(dev, qp, ohdr, ps))
476		return 1;
477
478	if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
479		if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND))
480			goto bail;
481		/* We are in the error state, flush the work request. */
482		if (qp->s_last == READ_ONCE(qp->s_head))
483			goto bail;
484		/* If DMAs are in progress, we can't flush immediately. */
485		if (iowait_sdma_pending(&priv->s_iowait)) {
486			qp->s_flags |= RVT_S_WAIT_DMA;
487			goto bail;
488		}
489		clear_ahg(qp);
490		wqe = rvt_get_swqe_ptr(qp, qp->s_last);
491		hfi1_trdma_send_complete(qp, wqe, qp->s_last != qp->s_acked ?
492					 IB_WC_SUCCESS : IB_WC_WR_FLUSH_ERR);
493		/* will get called again */
494		goto done_free_tx;
495	}
496
497	if (qp->s_flags & (RVT_S_WAIT_RNR | RVT_S_WAIT_ACK | HFI1_S_WAIT_HALT))
498		goto bail;
499
500	if (cmp_psn(qp->s_psn, qp->s_sending_hpsn) <= 0) {
501		if (cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0) {
502			qp->s_flags |= RVT_S_WAIT_PSN;
503			goto bail;
504		}
505		qp->s_sending_psn = qp->s_psn;
506		qp->s_sending_hpsn = qp->s_psn - 1;
507	}
508
509	/* Send a request. */
510	wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
511check_s_state:
512	switch (qp->s_state) {
513	default:
514		if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_NEXT_SEND_OK))
515			goto bail;
516		/*
517		 * Resend an old request or start a new one.
518		 *
519		 * We keep track of the current SWQE so that
520		 * we don't reset the "furthest progress" state
521		 * if we need to back up.
522		 */
523		newreq = 0;
524		if (qp->s_cur == qp->s_tail) {
525			/* Check if send work queue is empty. */
526			if (qp->s_tail == READ_ONCE(qp->s_head)) {
527				clear_ahg(qp);
528				goto bail;
529			}
530			/*
531			 * If a fence is requested, wait for previous
532			 * RDMA read and atomic operations to finish.
533			 * However, there is no need to guard against
534			 * TID RDMA READ after TID RDMA READ.
535			 */
536			if ((wqe->wr.send_flags & IB_SEND_FENCE) &&
537			    qp->s_num_rd_atomic &&
538			    (wqe->wr.opcode != IB_WR_TID_RDMA_READ ||
539			     priv->pending_tid_r_segs < qp->s_num_rd_atomic)) {
540				qp->s_flags |= RVT_S_WAIT_FENCE;
541				goto bail;
542			}
543			/*
544			 * Local operations are processed immediately
545			 * after all prior requests have completed
546			 */
547			if (wqe->wr.opcode == IB_WR_REG_MR ||
548			    wqe->wr.opcode == IB_WR_LOCAL_INV) {
549				int local_ops = 0;
550				int err = 0;
551
552				if (qp->s_last != qp->s_cur)
553					goto bail;
554				if (++qp->s_cur == qp->s_size)
555					qp->s_cur = 0;
556				if (++qp->s_tail == qp->s_size)
557					qp->s_tail = 0;
558				if (!(wqe->wr.send_flags &
559				      RVT_SEND_COMPLETION_ONLY)) {
560					err = rvt_invalidate_rkey(
561						qp,
562						wqe->wr.ex.invalidate_rkey);
563					local_ops = 1;
564				}
565				rvt_send_complete(qp, wqe,
566						  err ? IB_WC_LOC_PROT_ERR
567						      : IB_WC_SUCCESS);
568				if (local_ops)
569					atomic_dec(&qp->local_ops_pending);
570				goto done_free_tx;
571			}
572
573			newreq = 1;
574			qp->s_psn = wqe->psn;
575		}
576		/*
577		 * Note that we have to be careful not to modify the
578		 * original work request since we may need to resend
579		 * it.
580		 */
581		len = wqe->length;
582		ss = &qp->s_sge;
583		bth2 = mask_psn(qp->s_psn);
584
585		/*
586		 * Interlock between various IB requests and TID RDMA
587		 * if necessary.
588		 */
589		if ((priv->s_flags & HFI1_S_TID_WAIT_INTERLCK) ||
590		    hfi1_tid_rdma_wqe_interlock(qp, wqe))
591			goto bail;
592
593		switch (wqe->wr.opcode) {
594		case IB_WR_SEND:
595		case IB_WR_SEND_WITH_IMM:
596		case IB_WR_SEND_WITH_INV:
597			/* If no credit, return. */
598			if (!rvt_rc_credit_avail(qp, wqe))
599				goto bail;
600			if (len > pmtu) {
601				qp->s_state = OP(SEND_FIRST);
602				len = pmtu;
603				break;
604			}
605			if (wqe->wr.opcode == IB_WR_SEND) {
606				qp->s_state = OP(SEND_ONLY);
607			} else if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
608				qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE);
609				/* Immediate data comes after the BTH */
610				ohdr->u.imm_data = wqe->wr.ex.imm_data;
611				hwords += 1;
612			} else {
613				qp->s_state = OP(SEND_ONLY_WITH_INVALIDATE);
614				/* Invalidate rkey comes after the BTH */
615				ohdr->u.ieth = cpu_to_be32(
616						wqe->wr.ex.invalidate_rkey);
617				hwords += 1;
618			}
619			if (wqe->wr.send_flags & IB_SEND_SOLICITED)
620				bth0 |= IB_BTH_SOLICITED;
621			bth2 |= IB_BTH_REQ_ACK;
622			if (++qp->s_cur == qp->s_size)
623				qp->s_cur = 0;
624			break;
625
626		case IB_WR_RDMA_WRITE:
627			if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
628				qp->s_lsn++;
629			goto no_flow_control;
630		case IB_WR_RDMA_WRITE_WITH_IMM:
631			/* If no credit, return. */
632			if (!rvt_rc_credit_avail(qp, wqe))
633				goto bail;
634no_flow_control:
635			put_ib_reth_vaddr(
636				wqe->rdma_wr.remote_addr,
637				&ohdr->u.rc.reth);
638			ohdr->u.rc.reth.rkey =
639				cpu_to_be32(wqe->rdma_wr.rkey);
640			ohdr->u.rc.reth.length = cpu_to_be32(len);
641			hwords += sizeof(struct ib_reth) / sizeof(u32);
642			if (len > pmtu) {
643				qp->s_state = OP(RDMA_WRITE_FIRST);
644				len = pmtu;
645				break;
646			}
647			if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
648				qp->s_state = OP(RDMA_WRITE_ONLY);
649			} else {
650				qp->s_state =
651					OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE);
652				/* Immediate data comes after RETH */
653				ohdr->u.rc.imm_data = wqe->wr.ex.imm_data;
654				hwords += 1;
655				if (wqe->wr.send_flags & IB_SEND_SOLICITED)
656					bth0 |= IB_BTH_SOLICITED;
657			}
658			bth2 |= IB_BTH_REQ_ACK;
659			if (++qp->s_cur == qp->s_size)
660				qp->s_cur = 0;
661			break;
662
663		case IB_WR_TID_RDMA_WRITE:
664			if (newreq) {
665				/*
666				 * Limit the number of TID RDMA WRITE requests.
667				 */
668				if (atomic_read(&priv->n_tid_requests) >=
669				    HFI1_TID_RDMA_WRITE_CNT)
670					goto bail;
671
672				if (!(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
673					qp->s_lsn++;
674			}
675
676			hwords += hfi1_build_tid_rdma_write_req(qp, wqe, ohdr,
677								&bth1, &bth2,
678								&len);
679			ss = NULL;
680			if (priv->s_tid_cur == HFI1_QP_WQE_INVALID) {
681				priv->s_tid_cur = qp->s_cur;
682				if (priv->s_tid_tail == HFI1_QP_WQE_INVALID) {
683					priv->s_tid_tail = qp->s_cur;
684					priv->s_state = TID_OP(WRITE_RESP);
685				}
686			} else if (priv->s_tid_cur == priv->s_tid_head) {
687				struct rvt_swqe *__w;
688				struct tid_rdma_request *__r;
689
690				__w = rvt_get_swqe_ptr(qp, priv->s_tid_cur);
691				__r = wqe_to_tid_req(__w);
692
693				/*
694				 * The s_tid_cur pointer is advanced to s_cur if
695				 * any of the following conditions about the WQE
696				 * to which s_ti_cur currently points to are
697				 * satisfied:
698				 *   1. The request is not a TID RDMA WRITE
699				 *      request,
700				 *   2. The request is in the INACTIVE or
701				 *      COMPLETE states (TID RDMA READ requests
702				 *      stay at INACTIVE and TID RDMA WRITE
703				 *      transition to COMPLETE when done),
704				 *   3. The request is in the ACTIVE or SYNC
705				 *      state and the number of completed
706				 *      segments is equal to the total segment
707				 *      count.
708				 *      (If ACTIVE, the request is waiting for
709				 *       ACKs. If SYNC, the request has not
710				 *       received any responses because it's
711				 *       waiting on a sync point.)
712				 */
713				if (__w->wr.opcode != IB_WR_TID_RDMA_WRITE ||
714				    __r->state == TID_REQUEST_INACTIVE ||
715				    __r->state == TID_REQUEST_COMPLETE ||
716				    ((__r->state == TID_REQUEST_ACTIVE ||
717				      __r->state == TID_REQUEST_SYNC) &&
718				     __r->comp_seg == __r->total_segs)) {
719					if (priv->s_tid_tail ==
720					    priv->s_tid_cur &&
721					    priv->s_state ==
722					    TID_OP(WRITE_DATA_LAST)) {
723						priv->s_tid_tail = qp->s_cur;
724						priv->s_state =
725							TID_OP(WRITE_RESP);
726					}
727					priv->s_tid_cur = qp->s_cur;
728				}
729				/*
730				 * A corner case: when the last TID RDMA WRITE
731				 * request was completed, s_tid_head,
732				 * s_tid_cur, and s_tid_tail all point to the
733				 * same location. Other requests are posted and
734				 * s_cur wraps around to the same location,
735				 * where a new TID RDMA WRITE is posted. In
736				 * this case, none of the indices need to be
737				 * updated. However, the priv->s_state should.
738				 */
739				if (priv->s_tid_tail == qp->s_cur &&
740				    priv->s_state == TID_OP(WRITE_DATA_LAST))
741					priv->s_state = TID_OP(WRITE_RESP);
742			}
743			req = wqe_to_tid_req(wqe);
744			if (newreq) {
745				priv->s_tid_head = qp->s_cur;
746				priv->pending_tid_w_resp += req->total_segs;
747				atomic_inc(&priv->n_tid_requests);
748				atomic_dec(&priv->n_requests);
749			} else {
750				req->state = TID_REQUEST_RESEND;
751				req->comp_seg = delta_psn(bth2, wqe->psn);
752				/*
753				 * Pull back any segments since we are going
754				 * to re-receive them.
755				 */
756				req->setup_head = req->clear_tail;
757				priv->pending_tid_w_resp +=
758					delta_psn(wqe->lpsn, bth2) + 1;
759			}
760
761			trace_hfi1_tid_write_sender_make_req(qp, newreq);
762			trace_hfi1_tid_req_make_req_write(qp, newreq,
763							  wqe->wr.opcode,
764							  wqe->psn, wqe->lpsn,
765							  req);
766			if (++qp->s_cur == qp->s_size)
767				qp->s_cur = 0;
768			break;
769
770		case IB_WR_RDMA_READ:
771			/*
772			 * Don't allow more operations to be started
773			 * than the QP limits allow.
774			 */
775			if (qp->s_num_rd_atomic >=
776			    qp->s_max_rd_atomic) {
777				qp->s_flags |= RVT_S_WAIT_RDMAR;
778				goto bail;
779			}
780			qp->s_num_rd_atomic++;
781			if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
782				qp->s_lsn++;
783			put_ib_reth_vaddr(
784				wqe->rdma_wr.remote_addr,
785				&ohdr->u.rc.reth);
786			ohdr->u.rc.reth.rkey =
787				cpu_to_be32(wqe->rdma_wr.rkey);
788			ohdr->u.rc.reth.length = cpu_to_be32(len);
789			qp->s_state = OP(RDMA_READ_REQUEST);
790			hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
791			ss = NULL;
792			len = 0;
793			bth2 |= IB_BTH_REQ_ACK;
794			if (++qp->s_cur == qp->s_size)
795				qp->s_cur = 0;
796			break;
797
798		case IB_WR_TID_RDMA_READ:
799			trace_hfi1_tid_read_sender_make_req(qp, newreq);
800			wpriv = wqe->priv;
801			req = wqe_to_tid_req(wqe);
802			trace_hfi1_tid_req_make_req_read(qp, newreq,
803							 wqe->wr.opcode,
804							 wqe->psn, wqe->lpsn,
805							 req);
806			delta = cmp_psn(qp->s_psn, wqe->psn);
807
808			/*
809			 * Don't allow more operations to be started
810			 * than the QP limits allow. We could get here under
811			 * three conditions; (1) It's a new request; (2) We are
812			 * sending the second or later segment of a request,
813			 * but the qp->s_state is set to OP(RDMA_READ_REQUEST)
814			 * when the last segment of a previous request is
815			 * received just before this; (3) We are re-sending a
816			 * request.
817			 */
818			if (qp->s_num_rd_atomic >= qp->s_max_rd_atomic) {
819				qp->s_flags |= RVT_S_WAIT_RDMAR;
820				goto bail;
821			}
822			if (newreq) {
823				struct tid_rdma_flow *flow =
824					&req->flows[req->setup_head];
825
826				/*
827				 * Set up s_sge as it is needed for TID
828				 * allocation. However, if the pages have been
829				 * walked and mapped, skip it. An earlier try
830				 * has failed to allocate the TID entries.
831				 */
832				if (!flow->npagesets) {
833					qp->s_sge.sge = wqe->sg_list[0];
834					qp->s_sge.sg_list = wqe->sg_list + 1;
835					qp->s_sge.num_sge = wqe->wr.num_sge;
836					qp->s_sge.total_len = wqe->length;
837					qp->s_len = wqe->length;
838					req->isge = 0;
839					req->clear_tail = req->setup_head;
840					req->flow_idx = req->setup_head;
841					req->state = TID_REQUEST_ACTIVE;
842				}
843			} else if (delta == 0) {
844				/* Re-send a request */
845				req->cur_seg = 0;
846				req->comp_seg = 0;
847				req->ack_pending = 0;
848				req->flow_idx = req->clear_tail;
849				req->state = TID_REQUEST_RESEND;
850			}
851			req->s_next_psn = qp->s_psn;
852			/* Read one segment at a time */
853			len = min_t(u32, req->seg_len,
854				    wqe->length - req->seg_len * req->cur_seg);
855			delta = hfi1_build_tid_rdma_read_req(qp, wqe, ohdr,
856							     &bth1, &bth2,
857							     &len);
858			if (delta <= 0) {
859				/* Wait for TID space */
860				goto bail;
861			}
862			if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
863				qp->s_lsn++;
864			hwords += delta;
865			ss = &wpriv->ss;
866			/* Check if this is the last segment */
867			if (req->cur_seg >= req->total_segs &&
868			    ++qp->s_cur == qp->s_size)
869				qp->s_cur = 0;
870			break;
871
872		case IB_WR_ATOMIC_CMP_AND_SWP:
873		case IB_WR_ATOMIC_FETCH_AND_ADD:
874			/*
875			 * Don't allow more operations to be started
876			 * than the QP limits allow.
877			 */
878			if (qp->s_num_rd_atomic >=
879			    qp->s_max_rd_atomic) {
880				qp->s_flags |= RVT_S_WAIT_RDMAR;
881				goto bail;
882			}
883			qp->s_num_rd_atomic++;
884			fallthrough;
885		case IB_WR_OPFN:
886			if (newreq && !(qp->s_flags & RVT_S_UNLIMITED_CREDIT))
887				qp->s_lsn++;
888			if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
889			    wqe->wr.opcode == IB_WR_OPFN) {
890				qp->s_state = OP(COMPARE_SWAP);
891				put_ib_ateth_swap(wqe->atomic_wr.swap,
892						  &ohdr->u.atomic_eth);
893				put_ib_ateth_compare(wqe->atomic_wr.compare_add,
894						     &ohdr->u.atomic_eth);
895			} else {
896				qp->s_state = OP(FETCH_ADD);
897				put_ib_ateth_swap(wqe->atomic_wr.compare_add,
898						  &ohdr->u.atomic_eth);
899				put_ib_ateth_compare(0, &ohdr->u.atomic_eth);
900			}
901			put_ib_ateth_vaddr(wqe->atomic_wr.remote_addr,
902					   &ohdr->u.atomic_eth);
903			ohdr->u.atomic_eth.rkey = cpu_to_be32(
904				wqe->atomic_wr.rkey);
905			hwords += sizeof(struct ib_atomic_eth) / sizeof(u32);
906			ss = NULL;
907			len = 0;
908			bth2 |= IB_BTH_REQ_ACK;
909			if (++qp->s_cur == qp->s_size)
910				qp->s_cur = 0;
911			break;
912
913		default:
914			goto bail;
915		}
916		if (wqe->wr.opcode != IB_WR_TID_RDMA_READ) {
917			qp->s_sge.sge = wqe->sg_list[0];
918			qp->s_sge.sg_list = wqe->sg_list + 1;
919			qp->s_sge.num_sge = wqe->wr.num_sge;
920			qp->s_sge.total_len = wqe->length;
921			qp->s_len = wqe->length;
922		}
923		if (newreq) {
924			qp->s_tail++;
925			if (qp->s_tail >= qp->s_size)
926				qp->s_tail = 0;
927		}
928		if (wqe->wr.opcode == IB_WR_RDMA_READ ||
929		    wqe->wr.opcode == IB_WR_TID_RDMA_WRITE)
930			qp->s_psn = wqe->lpsn + 1;
931		else if (wqe->wr.opcode == IB_WR_TID_RDMA_READ)
932			qp->s_psn = req->s_next_psn;
933		else
934			qp->s_psn++;
935		break;
936
937	case OP(RDMA_READ_RESPONSE_FIRST):
938		/*
939		 * qp->s_state is normally set to the opcode of the
940		 * last packet constructed for new requests and therefore
941		 * is never set to RDMA read response.
942		 * RDMA_READ_RESPONSE_FIRST is used by the ACK processing
943		 * thread to indicate a SEND needs to be restarted from an
944		 * earlier PSN without interfering with the sending thread.
945		 * See restart_rc().
946		 */
947		qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
948		fallthrough;
949	case OP(SEND_FIRST):
950		qp->s_state = OP(SEND_MIDDLE);
951		fallthrough;
952	case OP(SEND_MIDDLE):
953		bth2 = mask_psn(qp->s_psn++);
954		ss = &qp->s_sge;
955		len = qp->s_len;
956		if (len > pmtu) {
957			len = pmtu;
958			middle = HFI1_CAP_IS_KSET(SDMA_AHG);
959			break;
960		}
961		if (wqe->wr.opcode == IB_WR_SEND) {
962			qp->s_state = OP(SEND_LAST);
963		} else if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
964			qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE);
965			/* Immediate data comes after the BTH */
966			ohdr->u.imm_data = wqe->wr.ex.imm_data;
967			hwords += 1;
968		} else {
969			qp->s_state = OP(SEND_LAST_WITH_INVALIDATE);
970			/* invalidate data comes after the BTH */
971			ohdr->u.ieth = cpu_to_be32(wqe->wr.ex.invalidate_rkey);
972			hwords += 1;
973		}
974		if (wqe->wr.send_flags & IB_SEND_SOLICITED)
975			bth0 |= IB_BTH_SOLICITED;
976		bth2 |= IB_BTH_REQ_ACK;
977		qp->s_cur++;
978		if (qp->s_cur >= qp->s_size)
979			qp->s_cur = 0;
980		break;
981
982	case OP(RDMA_READ_RESPONSE_LAST):
983		/*
984		 * qp->s_state is normally set to the opcode of the
985		 * last packet constructed for new requests and therefore
986		 * is never set to RDMA read response.
987		 * RDMA_READ_RESPONSE_LAST is used by the ACK processing
988		 * thread to indicate a RDMA write needs to be restarted from
989		 * an earlier PSN without interfering with the sending thread.
990		 * See restart_rc().
991		 */
992		qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, pmtu);
993		fallthrough;
994	case OP(RDMA_WRITE_FIRST):
995		qp->s_state = OP(RDMA_WRITE_MIDDLE);
996		fallthrough;
997	case OP(RDMA_WRITE_MIDDLE):
998		bth2 = mask_psn(qp->s_psn++);
999		ss = &qp->s_sge;
1000		len = qp->s_len;
1001		if (len > pmtu) {
1002			len = pmtu;
1003			middle = HFI1_CAP_IS_KSET(SDMA_AHG);
1004			break;
1005		}
1006		if (wqe->wr.opcode == IB_WR_RDMA_WRITE) {
1007			qp->s_state = OP(RDMA_WRITE_LAST);
1008		} else {
1009			qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE);
1010			/* Immediate data comes after the BTH */
1011			ohdr->u.imm_data = wqe->wr.ex.imm_data;
1012			hwords += 1;
1013			if (wqe->wr.send_flags & IB_SEND_SOLICITED)
1014				bth0 |= IB_BTH_SOLICITED;
1015		}
1016		bth2 |= IB_BTH_REQ_ACK;
1017		qp->s_cur++;
1018		if (qp->s_cur >= qp->s_size)
1019			qp->s_cur = 0;
1020		break;
1021
1022	case OP(RDMA_READ_RESPONSE_MIDDLE):
1023		/*
1024		 * qp->s_state is normally set to the opcode of the
1025		 * last packet constructed for new requests and therefore
1026		 * is never set to RDMA read response.
1027		 * RDMA_READ_RESPONSE_MIDDLE is used by the ACK processing
1028		 * thread to indicate a RDMA read needs to be restarted from
1029		 * an earlier PSN without interfering with the sending thread.
1030		 * See restart_rc().
1031		 */
1032		len = (delta_psn(qp->s_psn, wqe->psn)) * pmtu;
1033		put_ib_reth_vaddr(
1034			wqe->rdma_wr.remote_addr + len,
1035			&ohdr->u.rc.reth);
1036		ohdr->u.rc.reth.rkey =
1037			cpu_to_be32(wqe->rdma_wr.rkey);
1038		ohdr->u.rc.reth.length = cpu_to_be32(wqe->length - len);
1039		qp->s_state = OP(RDMA_READ_REQUEST);
1040		hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32);
1041		bth2 = mask_psn(qp->s_psn) | IB_BTH_REQ_ACK;
1042		qp->s_psn = wqe->lpsn + 1;
1043		ss = NULL;
1044		len = 0;
1045		qp->s_cur++;
1046		if (qp->s_cur == qp->s_size)
1047			qp->s_cur = 0;
1048		break;
1049
1050	case TID_OP(WRITE_RESP):
1051		/*
1052		 * This value for s_state is used for restarting a TID RDMA
1053		 * WRITE request. See comment in OP(RDMA_READ_RESPONSE_MIDDLE
1054		 * for more).
1055		 */
1056		req = wqe_to_tid_req(wqe);
1057		req->state = TID_REQUEST_RESEND;
1058		rcu_read_lock();
1059		remote = rcu_dereference(priv->tid_rdma.remote);
1060		req->comp_seg = delta_psn(qp->s_psn, wqe->psn);
1061		len = wqe->length - (req->comp_seg * remote->max_len);
1062		rcu_read_unlock();
1063
1064		bth2 = mask_psn(qp->s_psn);
1065		hwords += hfi1_build_tid_rdma_write_req(qp, wqe, ohdr, &bth1,
1066							&bth2, &len);
1067		qp->s_psn = wqe->lpsn + 1;
1068		ss = NULL;
1069		qp->s_state = TID_OP(WRITE_REQ);
1070		priv->pending_tid_w_resp += delta_psn(wqe->lpsn, bth2) + 1;
1071		priv->s_tid_cur = qp->s_cur;
1072		if (++qp->s_cur == qp->s_size)
1073			qp->s_cur = 0;
1074		trace_hfi1_tid_req_make_req_write(qp, 0, wqe->wr.opcode,
1075						  wqe->psn, wqe->lpsn, req);
1076		break;
1077
1078	case TID_OP(READ_RESP):
1079		if (wqe->wr.opcode != IB_WR_TID_RDMA_READ)
1080			goto bail;
1081		/* This is used to restart a TID read request */
1082		req = wqe_to_tid_req(wqe);
1083		wpriv = wqe->priv;
1084		/*
1085		 * Back down. The field qp->s_psn has been set to the psn with
1086		 * which the request should be restart. It's OK to use division
1087		 * as this is on the retry path.
1088		 */
1089		req->cur_seg = delta_psn(qp->s_psn, wqe->psn) / priv->pkts_ps;
1090
1091		/*
1092		 * The following function need to be redefined to return the
1093		 * status to make sure that we find the flow. At the same
1094		 * time, we can use the req->state change to check if the
1095		 * call succeeds or not.
1096		 */
1097		req->state = TID_REQUEST_RESEND;
1098		hfi1_tid_rdma_restart_req(qp, wqe, &bth2);
1099		if (req->state != TID_REQUEST_ACTIVE) {
1100			/*
1101			 * Failed to find the flow. Release all allocated tid
1102			 * resources.
1103			 */
1104			hfi1_kern_exp_rcv_clear_all(req);
1105			hfi1_kern_clear_hw_flow(priv->rcd, qp);
1106
1107			hfi1_trdma_send_complete(qp, wqe, IB_WC_LOC_QP_OP_ERR);
1108			goto bail;
1109		}
1110		req->state = TID_REQUEST_RESEND;
1111		len = min_t(u32, req->seg_len,
1112			    wqe->length - req->seg_len * req->cur_seg);
1113		flow = &req->flows[req->flow_idx];
1114		len -= flow->sent;
1115		req->s_next_psn = flow->flow_state.ib_lpsn + 1;
1116		delta = hfi1_build_tid_rdma_read_packet(wqe, ohdr, &bth1,
1117							&bth2, &len);
1118		if (delta <= 0) {
1119			/* Wait for TID space */
1120			goto bail;
1121		}
1122		hwords += delta;
1123		ss = &wpriv->ss;
1124		/* Check if this is the last segment */
1125		if (req->cur_seg >= req->total_segs &&
1126		    ++qp->s_cur == qp->s_size)
1127			qp->s_cur = 0;
1128		qp->s_psn = req->s_next_psn;
1129		trace_hfi1_tid_req_make_req_read(qp, 0, wqe->wr.opcode,
1130						 wqe->psn, wqe->lpsn, req);
1131		break;
1132	case TID_OP(READ_REQ):
1133		req = wqe_to_tid_req(wqe);
1134		delta = cmp_psn(qp->s_psn, wqe->psn);
1135		/*
1136		 * If the current WR is not TID RDMA READ, or this is the start
1137		 * of a new request, we need to change the qp->s_state so that
1138		 * the request can be set up properly.
1139		 */
1140		if (wqe->wr.opcode != IB_WR_TID_RDMA_READ || delta == 0 ||
1141		    qp->s_cur == qp->s_tail) {
1142			qp->s_state = OP(RDMA_READ_REQUEST);
1143			if (delta == 0 || qp->s_cur == qp->s_tail)
1144				goto check_s_state;
1145			else
1146				goto bail;
1147		}
1148
1149		/* Rate limiting */
1150		if (qp->s_num_rd_atomic >= qp->s_max_rd_atomic) {
1151			qp->s_flags |= RVT_S_WAIT_RDMAR;
1152			goto bail;
1153		}
1154
1155		wpriv = wqe->priv;
1156		/* Read one segment at a time */
1157		len = min_t(u32, req->seg_len,
1158			    wqe->length - req->seg_len * req->cur_seg);
1159		delta = hfi1_build_tid_rdma_read_req(qp, wqe, ohdr, &bth1,
1160						     &bth2, &len);
1161		if (delta <= 0) {
1162			/* Wait for TID space */
1163			goto bail;
1164		}
1165		hwords += delta;
1166		ss = &wpriv->ss;
1167		/* Check if this is the last segment */
1168		if (req->cur_seg >= req->total_segs &&
1169		    ++qp->s_cur == qp->s_size)
1170			qp->s_cur = 0;
1171		qp->s_psn = req->s_next_psn;
1172		trace_hfi1_tid_req_make_req_read(qp, 0, wqe->wr.opcode,
1173						 wqe->psn, wqe->lpsn, req);
1174		break;
1175	}
1176	qp->s_sending_hpsn = bth2;
1177	delta = delta_psn(bth2, wqe->psn);
1178	if (delta && delta % HFI1_PSN_CREDIT == 0 &&
1179	    wqe->wr.opcode != IB_WR_TID_RDMA_WRITE)
1180		bth2 |= IB_BTH_REQ_ACK;
1181	if (qp->s_flags & RVT_S_SEND_ONE) {
1182		qp->s_flags &= ~RVT_S_SEND_ONE;
1183		qp->s_flags |= RVT_S_WAIT_ACK;
1184		bth2 |= IB_BTH_REQ_ACK;
1185	}
1186	qp->s_len -= len;
1187	ps->s_txreq->hdr_dwords = hwords;
1188	ps->s_txreq->sde = priv->s_sde;
1189	ps->s_txreq->ss = ss;
1190	ps->s_txreq->s_cur_size = len;
1191	hfi1_make_ruc_header(
1192		qp,
1193		ohdr,
1194		bth0 | (qp->s_state << 24),
1195		bth1,
1196		bth2,
1197		middle,
1198		ps);
1199	return 1;
1200
1201done_free_tx:
1202	hfi1_put_txreq(ps->s_txreq);
1203	ps->s_txreq = NULL;
1204	return 1;
1205
1206bail:
1207	hfi1_put_txreq(ps->s_txreq);
1208
1209bail_no_tx:
1210	ps->s_txreq = NULL;
1211	qp->s_flags &= ~RVT_S_BUSY;
1212	/*
1213	 * If we didn't get a txreq, the QP will be woken up later to try
1214	 * again. Set the flags to indicate which work item to wake
1215	 * up.
1216	 */
1217	iowait_set_flag(&priv->s_iowait, IOWAIT_PENDING_IB);
1218	return 0;
1219}
1220
1221static inline void hfi1_make_bth_aeth(struct rvt_qp *qp,
1222				      struct ib_other_headers *ohdr,
1223				      u32 bth0, u32 bth1)
1224{
1225	if (qp->r_nak_state)
1226		ohdr->u.aeth = cpu_to_be32((qp->r_msn & IB_MSN_MASK) |
1227					    (qp->r_nak_state <<
1228					     IB_AETH_CREDIT_SHIFT));
1229	else
1230		ohdr->u.aeth = rvt_compute_aeth(qp);
1231
1232	ohdr->bth[0] = cpu_to_be32(bth0);
1233	ohdr->bth[1] = cpu_to_be32(bth1 | qp->remote_qpn);
1234	ohdr->bth[2] = cpu_to_be32(mask_psn(qp->r_ack_psn));
1235}
1236
1237static inline void hfi1_queue_rc_ack(struct hfi1_packet *packet, bool is_fecn)
1238{
1239	struct rvt_qp *qp = packet->qp;
1240	struct hfi1_ibport *ibp;
1241	unsigned long flags;
1242
1243	spin_lock_irqsave(&qp->s_lock, flags);
1244	if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK))
1245		goto unlock;
1246	ibp = rcd_to_iport(packet->rcd);
1247	this_cpu_inc(*ibp->rvp.rc_qacks);
1248	qp->s_flags |= RVT_S_ACK_PENDING | RVT_S_RESP_PENDING;
1249	qp->s_nak_state = qp->r_nak_state;
1250	qp->s_ack_psn = qp->r_ack_psn;
1251	if (is_fecn)
1252		qp->s_flags |= RVT_S_ECN;
1253
1254	/* Schedule the send tasklet. */
1255	hfi1_schedule_send(qp);
1256unlock:
1257	spin_unlock_irqrestore(&qp->s_lock, flags);
1258}
1259
1260static inline void hfi1_make_rc_ack_9B(struct hfi1_packet *packet,
1261				       struct hfi1_opa_header *opa_hdr,
1262				       u8 sc5, bool is_fecn,
1263				       u64 *pbc_flags, u32 *hwords,
1264				       u32 *nwords)
1265{
1266	struct rvt_qp *qp = packet->qp;
1267	struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
1268	struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1269	struct ib_header *hdr = &opa_hdr->ibh;
1270	struct ib_other_headers *ohdr;
1271	u16 lrh0 = HFI1_LRH_BTH;
1272	u16 pkey;
1273	u32 bth0, bth1;
1274
1275	opa_hdr->hdr_type = HFI1_PKT_TYPE_9B;
1276	ohdr = &hdr->u.oth;
1277	/* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4 */
1278	*hwords = 6;
1279
1280	if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)) {
1281		*hwords += hfi1_make_grh(ibp, &hdr->u.l.grh,
1282					 rdma_ah_read_grh(&qp->remote_ah_attr),
1283					 *hwords - 2, SIZE_OF_CRC);
1284		ohdr = &hdr->u.l.oth;
1285		lrh0 = HFI1_LRH_GRH;
1286	}
1287	/* set PBC_DC_INFO bit (aka SC[4]) in pbc_flags */
1288	*pbc_flags |= ((!!(sc5 & 0x10)) << PBC_DC_INFO_SHIFT);
1289
1290	/* read pkey_index w/o lock (its atomic) */
1291	pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
1292
1293	lrh0 |= (sc5 & IB_SC_MASK) << IB_SC_SHIFT |
1294		(rdma_ah_get_sl(&qp->remote_ah_attr) & IB_SL_MASK) <<
1295			IB_SL_SHIFT;
1296
1297	hfi1_make_ib_hdr(hdr, lrh0, *hwords + SIZE_OF_CRC,
1298			 opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr), 9B),
1299			 ppd->lid | rdma_ah_get_path_bits(&qp->remote_ah_attr));
1300
1301	bth0 = pkey | (OP(ACKNOWLEDGE) << 24);
1302	if (qp->s_mig_state == IB_MIG_MIGRATED)
1303		bth0 |= IB_BTH_MIG_REQ;
1304	bth1 = (!!is_fecn) << IB_BECN_SHIFT;
1305	/*
1306	 * Inline ACKs go out without the use of the Verbs send engine, so
1307	 * we need to set the STL Verbs Extended bit here
1308	 */
1309	bth1 |= HFI1_CAP_IS_KSET(OPFN) << IB_BTHE_E_SHIFT;
1310	hfi1_make_bth_aeth(qp, ohdr, bth0, bth1);
1311}
1312
1313static inline void hfi1_make_rc_ack_16B(struct hfi1_packet *packet,
1314					struct hfi1_opa_header *opa_hdr,
1315					u8 sc5, bool is_fecn,
1316					u64 *pbc_flags, u32 *hwords,
1317					u32 *nwords)
1318{
1319	struct rvt_qp *qp = packet->qp;
1320	struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
1321	struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1322	struct hfi1_16b_header *hdr = &opa_hdr->opah;
1323	struct ib_other_headers *ohdr;
1324	u32 bth0, bth1 = 0;
1325	u16 len, pkey;
1326	bool becn = is_fecn;
1327	u8 l4 = OPA_16B_L4_IB_LOCAL;
1328	u8 extra_bytes;
1329
1330	opa_hdr->hdr_type = HFI1_PKT_TYPE_16B;
1331	ohdr = &hdr->u.oth;
1332	/* header size in 32-bit words 16B LRH+BTH+AETH = (16+12+4)/4 */
1333	*hwords = 8;
1334	extra_bytes = hfi1_get_16b_padding(*hwords << 2, 0);
1335	*nwords = SIZE_OF_CRC + ((extra_bytes + SIZE_OF_LT) >> 2);
1336
1337	if (unlikely(rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
1338	    hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))) {
1339		*hwords += hfi1_make_grh(ibp, &hdr->u.l.grh,
1340					 rdma_ah_read_grh(&qp->remote_ah_attr),
1341					 *hwords - 4, *nwords);
1342		ohdr = &hdr->u.l.oth;
1343		l4 = OPA_16B_L4_IB_GLOBAL;
1344	}
1345	*pbc_flags |= PBC_PACKET_BYPASS | PBC_INSERT_BYPASS_ICRC;
1346
1347	/* read pkey_index w/o lock (its atomic) */
1348	pkey = hfi1_get_pkey(ibp, qp->s_pkey_index);
1349
1350	/* Convert dwords to flits */
1351	len = (*hwords + *nwords) >> 1;
1352
1353	hfi1_make_16b_hdr(hdr, ppd->lid |
1354			  (rdma_ah_get_path_bits(&qp->remote_ah_attr) &
1355			  ((1 << ppd->lmc) - 1)),
1356			  opa_get_lid(rdma_ah_get_dlid(&qp->remote_ah_attr),
1357				      16B), len, pkey, becn, 0, l4, sc5);
1358
1359	bth0 = pkey | (OP(ACKNOWLEDGE) << 24);
1360	bth0 |= extra_bytes << 20;
1361	if (qp->s_mig_state == IB_MIG_MIGRATED)
1362		bth1 = OPA_BTH_MIG_REQ;
1363	hfi1_make_bth_aeth(qp, ohdr, bth0, bth1);
1364}
1365
1366typedef void (*hfi1_make_rc_ack)(struct hfi1_packet *packet,
1367				 struct hfi1_opa_header *opa_hdr,
1368				 u8 sc5, bool is_fecn,
1369				 u64 *pbc_flags, u32 *hwords,
1370				 u32 *nwords);
1371
1372/* We support only two types - 9B and 16B for now */
1373static const hfi1_make_rc_ack hfi1_make_rc_ack_tbl[2] = {
1374	[HFI1_PKT_TYPE_9B] = &hfi1_make_rc_ack_9B,
1375	[HFI1_PKT_TYPE_16B] = &hfi1_make_rc_ack_16B
1376};
1377
1378/**
1379 * hfi1_send_rc_ack - Construct an ACK packet and send it
1380 * @qp: a pointer to the QP
1381 *
1382 * This is called from hfi1_rc_rcv() and handle_receive_interrupt().
1383 * Note that RDMA reads and atomics are handled in the
1384 * send side QP state and send engine.
1385 */
1386void hfi1_send_rc_ack(struct hfi1_packet *packet, bool is_fecn)
1387{
1388	struct hfi1_ctxtdata *rcd = packet->rcd;
1389	struct rvt_qp *qp = packet->qp;
1390	struct hfi1_ibport *ibp = rcd_to_iport(rcd);
1391	struct hfi1_qp_priv *priv = qp->priv;
1392	struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1393	u8 sc5 = ibp->sl_to_sc[rdma_ah_get_sl(&qp->remote_ah_attr)];
1394	u64 pbc, pbc_flags = 0;
1395	u32 hwords = 0;
1396	u32 nwords = 0;
1397	u32 plen;
1398	struct pio_buf *pbuf;
1399	struct hfi1_opa_header opa_hdr;
1400
1401	/* clear the defer count */
1402	qp->r_adefered = 0;
1403
1404	/* Don't send ACK or NAK if a RDMA read or atomic is pending. */
1405	if (qp->s_flags & RVT_S_RESP_PENDING) {
1406		hfi1_queue_rc_ack(packet, is_fecn);
1407		return;
1408	}
1409
1410	/* Ensure s_rdma_ack_cnt changes are committed */
1411	if (qp->s_rdma_ack_cnt) {
1412		hfi1_queue_rc_ack(packet, is_fecn);
1413		return;
1414	}
1415
1416	/* Don't try to send ACKs if the link isn't ACTIVE */
1417	if (driver_lstate(ppd) != IB_PORT_ACTIVE)
1418		return;
1419
1420	/* Make the appropriate header */
1421	hfi1_make_rc_ack_tbl[priv->hdr_type](packet, &opa_hdr, sc5, is_fecn,
1422					     &pbc_flags, &hwords, &nwords);
1423
1424	plen = 2 /* PBC */ + hwords + nwords;
1425	pbc = create_pbc(ppd, pbc_flags, qp->srate_mbps,
1426			 sc_to_vlt(ppd->dd, sc5), plen);
1427	pbuf = sc_buffer_alloc(rcd->sc, plen, NULL, NULL);
1428	if (IS_ERR_OR_NULL(pbuf)) {
1429		/*
1430		 * We have no room to send at the moment.  Pass
1431		 * responsibility for sending the ACK to the send engine
1432		 * so that when enough buffer space becomes available,
1433		 * the ACK is sent ahead of other outgoing packets.
1434		 */
1435		hfi1_queue_rc_ack(packet, is_fecn);
1436		return;
1437	}
1438	trace_ack_output_ibhdr(dd_from_ibdev(qp->ibqp.device),
1439			       &opa_hdr, ib_is_sc5(sc5));
1440
1441	/* write the pbc and data */
1442	ppd->dd->pio_inline_send(ppd->dd, pbuf, pbc,
1443				 (priv->hdr_type == HFI1_PKT_TYPE_9B ?
1444				 (void *)&opa_hdr.ibh :
1445				 (void *)&opa_hdr.opah), hwords);
1446	return;
1447}
1448
1449/**
1450 * update_num_rd_atomic - update the qp->s_num_rd_atomic
1451 * @qp: the QP
1452 * @psn: the packet sequence number to restart at
1453 * @wqe: the wqe
1454 *
1455 * This is called from reset_psn() to update qp->s_num_rd_atomic
1456 * for the current wqe.
1457 * Called at interrupt level with the QP s_lock held.
1458 */
1459static void update_num_rd_atomic(struct rvt_qp *qp, u32 psn,
1460				 struct rvt_swqe *wqe)
1461{
1462	u32 opcode = wqe->wr.opcode;
1463
1464	if (opcode == IB_WR_RDMA_READ ||
1465	    opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
1466	    opcode == IB_WR_ATOMIC_FETCH_AND_ADD) {
1467		qp->s_num_rd_atomic++;
1468	} else if (opcode == IB_WR_TID_RDMA_READ) {
1469		struct tid_rdma_request *req = wqe_to_tid_req(wqe);
1470		struct hfi1_qp_priv *priv = qp->priv;
1471
1472		if (cmp_psn(psn, wqe->lpsn) <= 0) {
1473			u32 cur_seg;
1474
1475			cur_seg = (psn - wqe->psn) / priv->pkts_ps;
1476			req->ack_pending = cur_seg - req->comp_seg;
1477			priv->pending_tid_r_segs += req->ack_pending;
1478			qp->s_num_rd_atomic += req->ack_pending;
1479			trace_hfi1_tid_req_update_num_rd_atomic(qp, 0,
1480								wqe->wr.opcode,
1481								wqe->psn,
1482								wqe->lpsn,
1483								req);
1484		} else {
1485			priv->pending_tid_r_segs += req->total_segs;
1486			qp->s_num_rd_atomic += req->total_segs;
1487		}
1488	}
1489}
1490
1491/**
1492 * reset_psn - reset the QP state to send starting from PSN
1493 * @qp: the QP
1494 * @psn: the packet sequence number to restart at
1495 *
1496 * This is called from hfi1_rc_rcv() to process an incoming RC ACK
1497 * for the given QP.
1498 * Called at interrupt level with the QP s_lock held.
1499 */
1500static void reset_psn(struct rvt_qp *qp, u32 psn)
1501{
1502	u32 n = qp->s_acked;
1503	struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, n);
1504	u32 opcode;
1505	struct hfi1_qp_priv *priv = qp->priv;
1506
1507	lockdep_assert_held(&qp->s_lock);
1508	qp->s_cur = n;
1509	priv->pending_tid_r_segs = 0;
1510	priv->pending_tid_w_resp = 0;
1511	qp->s_num_rd_atomic = 0;
1512
1513	/*
1514	 * If we are starting the request from the beginning,
1515	 * let the normal send code handle initialization.
1516	 */
1517	if (cmp_psn(psn, wqe->psn) <= 0) {
1518		qp->s_state = OP(SEND_LAST);
1519		goto done;
1520	}
1521	update_num_rd_atomic(qp, psn, wqe);
1522
1523	/* Find the work request opcode corresponding to the given PSN. */
1524	for (;;) {
1525		int diff;
1526
1527		if (++n == qp->s_size)
1528			n = 0;
1529		if (n == qp->s_tail)
1530			break;
1531		wqe = rvt_get_swqe_ptr(qp, n);
1532		diff = cmp_psn(psn, wqe->psn);
1533		if (diff < 0) {
1534			/* Point wqe back to the previous one*/
1535			wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
1536			break;
1537		}
1538		qp->s_cur = n;
1539		/*
1540		 * If we are starting the request from the beginning,
1541		 * let the normal send code handle initialization.
1542		 */
1543		if (diff == 0) {
1544			qp->s_state = OP(SEND_LAST);
1545			goto done;
1546		}
1547
1548		update_num_rd_atomic(qp, psn, wqe);
1549	}
1550	opcode = wqe->wr.opcode;
1551
1552	/*
1553	 * Set the state to restart in the middle of a request.
1554	 * Don't change the s_sge, s_cur_sge, or s_cur_size.
1555	 * See hfi1_make_rc_req().
1556	 */
1557	switch (opcode) {
1558	case IB_WR_SEND:
1559	case IB_WR_SEND_WITH_IMM:
1560		qp->s_state = OP(RDMA_READ_RESPONSE_FIRST);
1561		break;
1562
1563	case IB_WR_RDMA_WRITE:
1564	case IB_WR_RDMA_WRITE_WITH_IMM:
1565		qp->s_state = OP(RDMA_READ_RESPONSE_LAST);
1566		break;
1567
1568	case IB_WR_TID_RDMA_WRITE:
1569		qp->s_state = TID_OP(WRITE_RESP);
1570		break;
1571
1572	case IB_WR_RDMA_READ:
1573		qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE);
1574		break;
1575
1576	case IB_WR_TID_RDMA_READ:
1577		qp->s_state = TID_OP(READ_RESP);
1578		break;
1579
1580	default:
1581		/*
1582		 * This case shouldn't happen since its only
1583		 * one PSN per req.
1584		 */
1585		qp->s_state = OP(SEND_LAST);
1586	}
1587done:
1588	priv->s_flags &= ~HFI1_S_TID_WAIT_INTERLCK;
1589	qp->s_psn = psn;
1590	/*
1591	 * Set RVT_S_WAIT_PSN as rc_complete() may start the timer
1592	 * asynchronously before the send engine can get scheduled.
1593	 * Doing it in hfi1_make_rc_req() is too late.
1594	 */
1595	if ((cmp_psn(qp->s_psn, qp->s_sending_hpsn) <= 0) &&
1596	    (cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0))
1597		qp->s_flags |= RVT_S_WAIT_PSN;
1598	qp->s_flags &= ~HFI1_S_AHG_VALID;
1599	trace_hfi1_sender_reset_psn(qp);
1600}
1601
1602/*
1603 * Back up requester to resend the last un-ACKed request.
1604 * The QP r_lock and s_lock should be held and interrupts disabled.
1605 */
1606void hfi1_restart_rc(struct rvt_qp *qp, u32 psn, int wait)
1607{
1608	struct hfi1_qp_priv *priv = qp->priv;
1609	struct rvt_swqe *wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1610	struct hfi1_ibport *ibp;
1611
1612	lockdep_assert_held(&qp->r_lock);
1613	lockdep_assert_held(&qp->s_lock);
1614	trace_hfi1_sender_restart_rc(qp);
1615	if (qp->s_retry == 0) {
1616		if (qp->s_mig_state == IB_MIG_ARMED) {
1617			hfi1_migrate_qp(qp);
1618			qp->s_retry = qp->s_retry_cnt;
1619		} else if (qp->s_last == qp->s_acked) {
1620			/*
1621			 * We need special handling for the OPFN request WQEs as
1622			 * they are not allowed to generate real user errors
1623			 */
1624			if (wqe->wr.opcode == IB_WR_OPFN) {
1625				struct hfi1_ibport *ibp =
1626					to_iport(qp->ibqp.device, qp->port_num);
1627				/*
1628				 * Call opfn_conn_reply() with capcode and
1629				 * remaining data as 0 to close out the
1630				 * current request
1631				 */
1632				opfn_conn_reply(qp, priv->opfn.curr);
1633				wqe = do_rc_completion(qp, wqe, ibp);
1634				qp->s_flags &= ~RVT_S_WAIT_ACK;
1635			} else {
1636				trace_hfi1_tid_write_sender_restart_rc(qp, 0);
1637				if (wqe->wr.opcode == IB_WR_TID_RDMA_READ) {
1638					struct tid_rdma_request *req;
1639
1640					req = wqe_to_tid_req(wqe);
1641					hfi1_kern_exp_rcv_clear_all(req);
1642					hfi1_kern_clear_hw_flow(priv->rcd, qp);
1643				}
1644
1645				hfi1_trdma_send_complete(qp, wqe,
1646							 IB_WC_RETRY_EXC_ERR);
1647				rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
1648			}
1649			return;
1650		} else { /* need to handle delayed completion */
1651			return;
1652		}
1653	} else {
1654		qp->s_retry--;
1655	}
1656
1657	ibp = to_iport(qp->ibqp.device, qp->port_num);
1658	if (wqe->wr.opcode == IB_WR_RDMA_READ ||
1659	    wqe->wr.opcode == IB_WR_TID_RDMA_READ)
1660		ibp->rvp.n_rc_resends++;
1661	else
1662		ibp->rvp.n_rc_resends += delta_psn(qp->s_psn, psn);
1663
1664	qp->s_flags &= ~(RVT_S_WAIT_FENCE | RVT_S_WAIT_RDMAR |
1665			 RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_PSN |
1666			 RVT_S_WAIT_ACK | HFI1_S_WAIT_TID_RESP);
1667	if (wait)
1668		qp->s_flags |= RVT_S_SEND_ONE;
1669	reset_psn(qp, psn);
1670}
1671
1672/*
1673 * Set qp->s_sending_psn to the next PSN after the given one.
1674 * This would be psn+1 except when RDMA reads or TID RDMA ops
1675 * are present.
1676 */
1677static void reset_sending_psn(struct rvt_qp *qp, u32 psn)
1678{
1679	struct rvt_swqe *wqe;
1680	u32 n = qp->s_last;
1681
1682	lockdep_assert_held(&qp->s_lock);
1683	/* Find the work request corresponding to the given PSN. */
1684	for (;;) {
1685		wqe = rvt_get_swqe_ptr(qp, n);
1686		if (cmp_psn(psn, wqe->lpsn) <= 0) {
1687			if (wqe->wr.opcode == IB_WR_RDMA_READ ||
1688			    wqe->wr.opcode == IB_WR_TID_RDMA_READ ||
1689			    wqe->wr.opcode == IB_WR_TID_RDMA_WRITE)
1690				qp->s_sending_psn = wqe->lpsn + 1;
1691			else
1692				qp->s_sending_psn = psn + 1;
1693			break;
1694		}
1695		if (++n == qp->s_size)
1696			n = 0;
1697		if (n == qp->s_tail)
1698			break;
1699	}
1700}
1701
1702/**
1703 * hfi1_rc_verbs_aborted - handle abort status
1704 * @qp: the QP
1705 * @opah: the opa header
1706 *
1707 * This code modifies both ACK bit in BTH[2]
1708 * and the s_flags to go into send one mode.
1709 *
1710 * This serves to throttle the send engine to only
1711 * send a single packet in the likely case the
1712 * a link has gone down.
1713 */
1714void hfi1_rc_verbs_aborted(struct rvt_qp *qp, struct hfi1_opa_header *opah)
1715{
1716	struct ib_other_headers *ohdr = hfi1_get_rc_ohdr(opah);
1717	u8 opcode = ib_bth_get_opcode(ohdr);
1718	u32 psn;
1719
1720	/* ignore responses */
1721	if ((opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1722	     opcode <= OP(ATOMIC_ACKNOWLEDGE)) ||
1723	    opcode == TID_OP(READ_RESP) ||
1724	    opcode == TID_OP(WRITE_RESP))
1725		return;
1726
1727	psn = ib_bth_get_psn(ohdr) | IB_BTH_REQ_ACK;
1728	ohdr->bth[2] = cpu_to_be32(psn);
1729	qp->s_flags |= RVT_S_SEND_ONE;
1730}
1731
1732/*
1733 * This should be called with the QP s_lock held and interrupts disabled.
1734 */
1735void hfi1_rc_send_complete(struct rvt_qp *qp, struct hfi1_opa_header *opah)
1736{
1737	struct ib_other_headers *ohdr;
1738	struct hfi1_qp_priv *priv = qp->priv;
1739	struct rvt_swqe *wqe;
1740	u32 opcode, head, tail;
1741	u32 psn;
1742	struct tid_rdma_request *req;
1743
1744	lockdep_assert_held(&qp->s_lock);
1745	if (!(ib_rvt_state_ops[qp->state] & RVT_SEND_OR_FLUSH_OR_RECV_OK))
1746		return;
1747
1748	ohdr = hfi1_get_rc_ohdr(opah);
1749	opcode = ib_bth_get_opcode(ohdr);
1750	if ((opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
1751	     opcode <= OP(ATOMIC_ACKNOWLEDGE)) ||
1752	    opcode == TID_OP(READ_RESP) ||
1753	    opcode == TID_OP(WRITE_RESP)) {
1754		WARN_ON(!qp->s_rdma_ack_cnt);
1755		qp->s_rdma_ack_cnt--;
1756		return;
1757	}
1758
1759	psn = ib_bth_get_psn(ohdr);
1760	/*
1761	 * Don't attempt to reset the sending PSN for packets in the
1762	 * KDETH PSN space since the PSN does not match anything.
1763	 */
1764	if (opcode != TID_OP(WRITE_DATA) &&
1765	    opcode != TID_OP(WRITE_DATA_LAST) &&
1766	    opcode != TID_OP(ACK) && opcode != TID_OP(RESYNC))
1767		reset_sending_psn(qp, psn);
1768
1769	/* Handle TID RDMA WRITE packets differently */
1770	if (opcode >= TID_OP(WRITE_REQ) &&
1771	    opcode <= TID_OP(WRITE_DATA_LAST)) {
1772		head = priv->s_tid_head;
1773		tail = priv->s_tid_cur;
1774		/*
1775		 * s_tid_cur is set to s_tid_head in the case, where
1776		 * a new TID RDMA request is being started and all
1777		 * previous ones have been completed.
1778		 * Therefore, we need to do a secondary check in order
1779		 * to properly determine whether we should start the
1780		 * RC timer.
1781		 */
1782		wqe = rvt_get_swqe_ptr(qp, tail);
1783		req = wqe_to_tid_req(wqe);
1784		if (head == tail && req->comp_seg < req->total_segs) {
1785			if (tail == 0)
1786				tail = qp->s_size - 1;
1787			else
1788				tail -= 1;
1789		}
1790	} else {
1791		head = qp->s_tail;
1792		tail = qp->s_acked;
1793	}
1794
1795	/*
1796	 * Start timer after a packet requesting an ACK has been sent and
1797	 * there are still requests that haven't been acked.
1798	 */
1799	if ((psn & IB_BTH_REQ_ACK) && tail != head &&
1800	    opcode != TID_OP(WRITE_DATA) && opcode != TID_OP(WRITE_DATA_LAST) &&
1801	    opcode != TID_OP(RESYNC) &&
1802	    !(qp->s_flags &
1803	      (RVT_S_TIMER | RVT_S_WAIT_RNR | RVT_S_WAIT_PSN)) &&
1804	    (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) {
1805		if (opcode == TID_OP(READ_REQ))
1806			rvt_add_retry_timer_ext(qp, priv->timeout_shift);
1807		else
1808			rvt_add_retry_timer(qp);
1809	}
1810
1811	/* Start TID RDMA ACK timer */
1812	if ((opcode == TID_OP(WRITE_DATA) ||
1813	     opcode == TID_OP(WRITE_DATA_LAST) ||
1814	     opcode == TID_OP(RESYNC)) &&
1815	    (psn & IB_BTH_REQ_ACK) &&
1816	    !(priv->s_flags & HFI1_S_TID_RETRY_TIMER) &&
1817	    (ib_rvt_state_ops[qp->state] & RVT_PROCESS_RECV_OK)) {
1818		/*
1819		 * The TID RDMA ACK packet could be received before this
1820		 * function is called. Therefore, add the timer only if TID
1821		 * RDMA ACK packets are actually pending.
1822		 */
1823		wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1824		req = wqe_to_tid_req(wqe);
1825		if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE &&
1826		    req->ack_seg < req->cur_seg)
1827			hfi1_add_tid_retry_timer(qp);
1828	}
1829
1830	while (qp->s_last != qp->s_acked) {
1831		wqe = rvt_get_swqe_ptr(qp, qp->s_last);
1832		if (cmp_psn(wqe->lpsn, qp->s_sending_psn) >= 0 &&
1833		    cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) <= 0)
1834			break;
1835		trdma_clean_swqe(qp, wqe);
1836		trace_hfi1_qp_send_completion(qp, wqe, qp->s_last);
1837		rvt_qp_complete_swqe(qp,
1838				     wqe,
1839				     ib_hfi1_wc_opcode[wqe->wr.opcode],
1840				     IB_WC_SUCCESS);
1841	}
1842	/*
1843	 * If we were waiting for sends to complete before re-sending,
1844	 * and they are now complete, restart sending.
1845	 */
1846	trace_hfi1_sendcomplete(qp, psn);
1847	if (qp->s_flags & RVT_S_WAIT_PSN &&
1848	    cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
1849		qp->s_flags &= ~RVT_S_WAIT_PSN;
1850		qp->s_sending_psn = qp->s_psn;
1851		qp->s_sending_hpsn = qp->s_psn - 1;
1852		hfi1_schedule_send(qp);
1853	}
1854}
1855
1856static inline void update_last_psn(struct rvt_qp *qp, u32 psn)
1857{
1858	qp->s_last_psn = psn;
1859}
1860
1861/*
1862 * Generate a SWQE completion.
1863 * This is similar to hfi1_send_complete but has to check to be sure
1864 * that the SGEs are not being referenced if the SWQE is being resent.
1865 */
1866struct rvt_swqe *do_rc_completion(struct rvt_qp *qp,
1867				  struct rvt_swqe *wqe,
1868				  struct hfi1_ibport *ibp)
1869{
1870	struct hfi1_qp_priv *priv = qp->priv;
1871
1872	lockdep_assert_held(&qp->s_lock);
1873	/*
1874	 * Don't decrement refcount and don't generate a
1875	 * completion if the SWQE is being resent until the send
1876	 * is finished.
1877	 */
1878	trace_hfi1_rc_completion(qp, wqe->lpsn);
1879	if (cmp_psn(wqe->lpsn, qp->s_sending_psn) < 0 ||
1880	    cmp_psn(qp->s_sending_psn, qp->s_sending_hpsn) > 0) {
1881		trdma_clean_swqe(qp, wqe);
1882		trace_hfi1_qp_send_completion(qp, wqe, qp->s_last);
1883		rvt_qp_complete_swqe(qp,
1884				     wqe,
1885				     ib_hfi1_wc_opcode[wqe->wr.opcode],
1886				     IB_WC_SUCCESS);
1887	} else {
1888		struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
1889
1890		this_cpu_inc(*ibp->rvp.rc_delayed_comp);
1891		/*
1892		 * If send progress not running attempt to progress
1893		 * SDMA queue.
1894		 */
1895		if (ppd->dd->flags & HFI1_HAS_SEND_DMA) {
1896			struct sdma_engine *engine;
1897			u8 sl = rdma_ah_get_sl(&qp->remote_ah_attr);
1898			u8 sc5;
1899
1900			/* For now use sc to find engine */
1901			sc5 = ibp->sl_to_sc[sl];
1902			engine = qp_to_sdma_engine(qp, sc5);
1903			sdma_engine_progress_schedule(engine);
1904		}
1905	}
1906
1907	qp->s_retry = qp->s_retry_cnt;
1908	/*
1909	 * Don't update the last PSN if the request being completed is
1910	 * a TID RDMA WRITE request.
1911	 * Completion of the TID RDMA WRITE requests are done by the
1912	 * TID RDMA ACKs and as such could be for a request that has
1913	 * already been ACKed as far as the IB state machine is
1914	 * concerned.
1915	 */
1916	if (wqe->wr.opcode != IB_WR_TID_RDMA_WRITE)
1917		update_last_psn(qp, wqe->lpsn);
1918
1919	/*
1920	 * If we are completing a request which is in the process of
1921	 * being resent, we can stop re-sending it since we know the
1922	 * responder has already seen it.
1923	 */
1924	if (qp->s_acked == qp->s_cur) {
1925		if (++qp->s_cur >= qp->s_size)
1926			qp->s_cur = 0;
1927		qp->s_acked = qp->s_cur;
1928		wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
1929		if (qp->s_acked != qp->s_tail) {
1930			qp->s_state = OP(SEND_LAST);
1931			qp->s_psn = wqe->psn;
1932		}
1933	} else {
1934		if (++qp->s_acked >= qp->s_size)
1935			qp->s_acked = 0;
1936		if (qp->state == IB_QPS_SQD && qp->s_acked == qp->s_cur)
1937			qp->s_draining = 0;
1938		wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
1939	}
1940	if (priv->s_flags & HFI1_S_TID_WAIT_INTERLCK) {
1941		priv->s_flags &= ~HFI1_S_TID_WAIT_INTERLCK;
1942		hfi1_schedule_send(qp);
1943	}
1944	return wqe;
1945}
1946
1947static void set_restart_qp(struct rvt_qp *qp, struct hfi1_ctxtdata *rcd)
1948{
1949	/* Retry this request. */
1950	if (!(qp->r_flags & RVT_R_RDMAR_SEQ)) {
1951		qp->r_flags |= RVT_R_RDMAR_SEQ;
1952		hfi1_restart_rc(qp, qp->s_last_psn + 1, 0);
1953		if (list_empty(&qp->rspwait)) {
1954			qp->r_flags |= RVT_R_RSP_SEND;
1955			rvt_get_qp(qp);
1956			list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
1957		}
1958	}
1959}
1960
1961/**
1962 * update_qp_retry_state - Update qp retry state.
1963 * @qp: the QP
1964 * @psn: the packet sequence number of the TID RDMA WRITE RESP.
1965 * @spsn:  The start psn for the given TID RDMA WRITE swqe.
1966 * @lpsn:  The last psn for the given TID RDMA WRITE swqe.
1967 *
1968 * This function is called to update the qp retry state upon
1969 * receiving a TID WRITE RESP after the qp is scheduled to retry
1970 * a request.
1971 */
1972static void update_qp_retry_state(struct rvt_qp *qp, u32 psn, u32 spsn,
1973				  u32 lpsn)
1974{
1975	struct hfi1_qp_priv *qpriv = qp->priv;
1976
1977	qp->s_psn = psn + 1;
1978	/*
1979	 * If this is the first TID RDMA WRITE RESP packet for the current
1980	 * request, change the s_state so that the retry will be processed
1981	 * correctly. Similarly, if this is the last TID RDMA WRITE RESP
1982	 * packet, change the s_state and advance the s_cur.
1983	 */
1984	if (cmp_psn(psn, lpsn) >= 0) {
1985		qp->s_cur = qpriv->s_tid_cur + 1;
1986		if (qp->s_cur >= qp->s_size)
1987			qp->s_cur = 0;
1988		qp->s_state = TID_OP(WRITE_REQ);
1989	} else  if (!cmp_psn(psn, spsn)) {
1990		qp->s_cur = qpriv->s_tid_cur;
1991		qp->s_state = TID_OP(WRITE_RESP);
1992	}
1993}
1994
1995/**
1996 * do_rc_ack - process an incoming RC ACK
1997 * @qp: the QP the ACK came in on
1998 * @psn: the packet sequence number of the ACK
1999 * @opcode: the opcode of the request that resulted in the ACK
2000 *
2001 * This is called from rc_rcv_resp() to process an incoming RC ACK
2002 * for the given QP.
2003 * May be called at interrupt level, with the QP s_lock held.
2004 * Returns 1 if OK, 0 if current operation should be aborted (NAK).
2005 */
2006int do_rc_ack(struct rvt_qp *qp, u32 aeth, u32 psn, int opcode,
2007	      u64 val, struct hfi1_ctxtdata *rcd)
2008{
2009	struct hfi1_ibport *ibp;
2010	enum ib_wc_status status;
2011	struct hfi1_qp_priv *qpriv = qp->priv;
2012	struct rvt_swqe *wqe;
2013	int ret = 0;
2014	u32 ack_psn;
2015	int diff;
2016	struct rvt_dev_info *rdi;
2017
2018	lockdep_assert_held(&qp->s_lock);
2019	/*
2020	 * Note that NAKs implicitly ACK outstanding SEND and RDMA write
2021	 * requests and implicitly NAK RDMA read and atomic requests issued
2022	 * before the NAK'ed request.  The MSN won't include the NAK'ed
2023	 * request but will include an ACK'ed request(s).
2024	 */
2025	ack_psn = psn;
2026	if (aeth >> IB_AETH_NAK_SHIFT)
2027		ack_psn--;
2028	wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2029	ibp = rcd_to_iport(rcd);
2030
2031	/*
2032	 * The MSN might be for a later WQE than the PSN indicates so
2033	 * only complete WQEs that the PSN finishes.
2034	 */
2035	while ((diff = delta_psn(ack_psn, wqe->lpsn)) >= 0) {
2036		/*
2037		 * RDMA_READ_RESPONSE_ONLY is a special case since
2038		 * we want to generate completion events for everything
2039		 * before the RDMA read, copy the data, then generate
2040		 * the completion for the read.
2041		 */
2042		if (wqe->wr.opcode == IB_WR_RDMA_READ &&
2043		    opcode == OP(RDMA_READ_RESPONSE_ONLY) &&
2044		    diff == 0) {
2045			ret = 1;
2046			goto bail_stop;
2047		}
2048		/*
2049		 * If this request is a RDMA read or atomic, and the ACK is
2050		 * for a later operation, this ACK NAKs the RDMA read or
2051		 * atomic.  In other words, only a RDMA_READ_LAST or ONLY
2052		 * can ACK a RDMA read and likewise for atomic ops.  Note
2053		 * that the NAK case can only happen if relaxed ordering is
2054		 * used and requests are sent after an RDMA read or atomic
2055		 * is sent but before the response is received.
2056		 */
2057		if ((wqe->wr.opcode == IB_WR_RDMA_READ &&
2058		     (opcode != OP(RDMA_READ_RESPONSE_LAST) || diff != 0)) ||
2059		    (wqe->wr.opcode == IB_WR_TID_RDMA_READ &&
2060		     (opcode != TID_OP(READ_RESP) || diff != 0)) ||
2061		    ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2062		      wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) &&
2063		     (opcode != OP(ATOMIC_ACKNOWLEDGE) || diff != 0)) ||
2064		    (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE &&
2065		     (delta_psn(psn, qp->s_last_psn) != 1))) {
2066			set_restart_qp(qp, rcd);
2067			/*
2068			 * No need to process the ACK/NAK since we are
2069			 * restarting an earlier request.
2070			 */
2071			goto bail_stop;
2072		}
2073		if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2074		    wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) {
2075			u64 *vaddr = wqe->sg_list[0].vaddr;
2076			*vaddr = val;
2077		}
2078		if (wqe->wr.opcode == IB_WR_OPFN)
2079			opfn_conn_reply(qp, val);
2080
2081		if (qp->s_num_rd_atomic &&
2082		    (wqe->wr.opcode == IB_WR_RDMA_READ ||
2083		     wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2084		     wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)) {
2085			qp->s_num_rd_atomic--;
2086			/* Restart sending task if fence is complete */
2087			if ((qp->s_flags & RVT_S_WAIT_FENCE) &&
2088			    !qp->s_num_rd_atomic) {
2089				qp->s_flags &= ~(RVT_S_WAIT_FENCE |
2090						 RVT_S_WAIT_ACK);
2091				hfi1_schedule_send(qp);
2092			} else if (qp->s_flags & RVT_S_WAIT_RDMAR) {
2093				qp->s_flags &= ~(RVT_S_WAIT_RDMAR |
2094						 RVT_S_WAIT_ACK);
2095				hfi1_schedule_send(qp);
2096			}
2097		}
2098
2099		/*
2100		 * TID RDMA WRITE requests will be completed by the TID RDMA
2101		 * ACK packet handler (see tid_rdma.c).
2102		 */
2103		if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE)
2104			break;
2105
2106		wqe = do_rc_completion(qp, wqe, ibp);
2107		if (qp->s_acked == qp->s_tail)
2108			break;
2109	}
2110
2111	trace_hfi1_rc_ack_do(qp, aeth, psn, wqe);
2112	trace_hfi1_sender_do_rc_ack(qp);
2113	switch (aeth >> IB_AETH_NAK_SHIFT) {
2114	case 0:         /* ACK */
2115		this_cpu_inc(*ibp->rvp.rc_acks);
2116		if (wqe->wr.opcode == IB_WR_TID_RDMA_READ) {
2117			if (wqe_to_tid_req(wqe)->ack_pending)
2118				rvt_mod_retry_timer_ext(qp,
2119							qpriv->timeout_shift);
2120			else
2121				rvt_stop_rc_timers(qp);
2122		} else if (qp->s_acked != qp->s_tail) {
2123			struct rvt_swqe *__w = NULL;
2124
2125			if (qpriv->s_tid_cur != HFI1_QP_WQE_INVALID)
2126				__w = rvt_get_swqe_ptr(qp, qpriv->s_tid_cur);
2127
2128			/*
2129			 * Stop timers if we've received all of the TID RDMA
2130			 * WRITE * responses.
2131			 */
2132			if (__w && __w->wr.opcode == IB_WR_TID_RDMA_WRITE &&
2133			    opcode == TID_OP(WRITE_RESP)) {
2134				/*
2135				 * Normally, the loop above would correctly
2136				 * process all WQEs from s_acked onward and
2137				 * either complete them or check for correct
2138				 * PSN sequencing.
2139				 * However, for TID RDMA, due to pipelining,
2140				 * the response may not be for the request at
2141				 * s_acked so the above look would just be
2142				 * skipped. This does not allow for checking
2143				 * the PSN sequencing. It has to be done
2144				 * separately.
2145				 */
2146				if (cmp_psn(psn, qp->s_last_psn + 1)) {
2147					set_restart_qp(qp, rcd);
2148					goto bail_stop;
2149				}
2150				/*
2151				 * If the psn is being resent, stop the
2152				 * resending.
2153				 */
2154				if (qp->s_cur != qp->s_tail &&
2155				    cmp_psn(qp->s_psn, psn) <= 0)
2156					update_qp_retry_state(qp, psn,
2157							      __w->psn,
2158							      __w->lpsn);
2159				else if (--qpriv->pending_tid_w_resp)
2160					rvt_mod_retry_timer(qp);
2161				else
2162					rvt_stop_rc_timers(qp);
2163			} else {
2164				/*
2165				 * We are expecting more ACKs so
2166				 * mod the retry timer.
2167				 */
2168				rvt_mod_retry_timer(qp);
2169				/*
2170				 * We can stop re-sending the earlier packets
2171				 * and continue with the next packet the
2172				 * receiver wants.
2173				 */
2174				if (cmp_psn(qp->s_psn, psn) <= 0)
2175					reset_psn(qp, psn + 1);
2176			}
2177		} else {
2178			/* No more acks - kill all timers */
2179			rvt_stop_rc_timers(qp);
2180			if (cmp_psn(qp->s_psn, psn) <= 0) {
2181				qp->s_state = OP(SEND_LAST);
2182				qp->s_psn = psn + 1;
2183			}
2184		}
2185		if (qp->s_flags & RVT_S_WAIT_ACK) {
2186			qp->s_flags &= ~RVT_S_WAIT_ACK;
2187			hfi1_schedule_send(qp);
2188		}
2189		rvt_get_credit(qp, aeth);
2190		qp->s_rnr_retry = qp->s_rnr_retry_cnt;
2191		qp->s_retry = qp->s_retry_cnt;
2192		/*
2193		 * If the current request is a TID RDMA WRITE request and the
2194		 * response is not a TID RDMA WRITE RESP packet, s_last_psn
2195		 * can't be advanced.
2196		 */
2197		if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE &&
2198		    opcode != TID_OP(WRITE_RESP) &&
2199		    cmp_psn(psn, wqe->psn) >= 0)
2200			return 1;
2201		update_last_psn(qp, psn);
2202		return 1;
2203
2204	case 1:         /* RNR NAK */
2205		ibp->rvp.n_rnr_naks++;
2206		if (qp->s_acked == qp->s_tail)
2207			goto bail_stop;
2208		if (qp->s_flags & RVT_S_WAIT_RNR)
2209			goto bail_stop;
2210		rdi = ib_to_rvt(qp->ibqp.device);
2211		if (!(rdi->post_parms[wqe->wr.opcode].flags &
2212		       RVT_OPERATION_IGN_RNR_CNT)) {
2213			if (qp->s_rnr_retry == 0) {
2214				status = IB_WC_RNR_RETRY_EXC_ERR;
2215				goto class_b;
2216			}
2217			if (qp->s_rnr_retry_cnt < 7 && qp->s_rnr_retry_cnt > 0)
2218				qp->s_rnr_retry--;
2219		}
2220
2221		/*
2222		 * The last valid PSN is the previous PSN. For TID RDMA WRITE
2223		 * request, s_last_psn should be incremented only when a TID
2224		 * RDMA WRITE RESP is received to avoid skipping lost TID RDMA
2225		 * WRITE RESP packets.
2226		 */
2227		if (wqe->wr.opcode == IB_WR_TID_RDMA_WRITE) {
2228			reset_psn(qp, qp->s_last_psn + 1);
2229		} else {
2230			update_last_psn(qp, psn - 1);
2231			reset_psn(qp, psn);
2232		}
2233
2234		ibp->rvp.n_rc_resends += delta_psn(qp->s_psn, psn);
2235		qp->s_flags &= ~(RVT_S_WAIT_SSN_CREDIT | RVT_S_WAIT_ACK);
2236		rvt_stop_rc_timers(qp);
2237		rvt_add_rnr_timer(qp, aeth);
2238		return 0;
2239
2240	case 3:         /* NAK */
2241		if (qp->s_acked == qp->s_tail)
2242			goto bail_stop;
2243		/* The last valid PSN is the previous PSN. */
2244		update_last_psn(qp, psn - 1);
2245		switch ((aeth >> IB_AETH_CREDIT_SHIFT) &
2246			IB_AETH_CREDIT_MASK) {
2247		case 0: /* PSN sequence error */
2248			ibp->rvp.n_seq_naks++;
2249			/*
2250			 * Back up to the responder's expected PSN.
2251			 * Note that we might get a NAK in the middle of an
2252			 * RDMA READ response which terminates the RDMA
2253			 * READ.
2254			 */
2255			hfi1_restart_rc(qp, psn, 0);
2256			hfi1_schedule_send(qp);
2257			break;
2258
2259		case 1: /* Invalid Request */
2260			status = IB_WC_REM_INV_REQ_ERR;
2261			ibp->rvp.n_other_naks++;
2262			goto class_b;
2263
2264		case 2: /* Remote Access Error */
2265			status = IB_WC_REM_ACCESS_ERR;
2266			ibp->rvp.n_other_naks++;
2267			goto class_b;
2268
2269		case 3: /* Remote Operation Error */
2270			status = IB_WC_REM_OP_ERR;
2271			ibp->rvp.n_other_naks++;
2272class_b:
2273			if (qp->s_last == qp->s_acked) {
2274				if (wqe->wr.opcode == IB_WR_TID_RDMA_READ)
2275					hfi1_kern_read_tid_flow_free(qp);
2276
2277				hfi1_trdma_send_complete(qp, wqe, status);
2278				rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
2279			}
2280			break;
2281
2282		default:
2283			/* Ignore other reserved NAK error codes */
2284			goto reserved;
2285		}
2286		qp->s_retry = qp->s_retry_cnt;
2287		qp->s_rnr_retry = qp->s_rnr_retry_cnt;
2288		goto bail_stop;
2289
2290	default:                /* 2: reserved */
2291reserved:
2292		/* Ignore reserved NAK codes. */
2293		goto bail_stop;
2294	}
2295	/* cannot be reached  */
2296bail_stop:
2297	rvt_stop_rc_timers(qp);
2298	return ret;
2299}
2300
2301/*
2302 * We have seen an out of sequence RDMA read middle or last packet.
2303 * This ACKs SENDs and RDMA writes up to the first RDMA read or atomic SWQE.
2304 */
2305static void rdma_seq_err(struct rvt_qp *qp, struct hfi1_ibport *ibp, u32 psn,
2306			 struct hfi1_ctxtdata *rcd)
2307{
2308	struct rvt_swqe *wqe;
2309
2310	lockdep_assert_held(&qp->s_lock);
2311	/* Remove QP from retry timer */
2312	rvt_stop_rc_timers(qp);
2313
2314	wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2315
2316	while (cmp_psn(psn, wqe->lpsn) > 0) {
2317		if (wqe->wr.opcode == IB_WR_RDMA_READ ||
2318		    wqe->wr.opcode == IB_WR_TID_RDMA_READ ||
2319		    wqe->wr.opcode == IB_WR_TID_RDMA_WRITE ||
2320		    wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP ||
2321		    wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)
2322			break;
2323		wqe = do_rc_completion(qp, wqe, ibp);
2324	}
2325
2326	ibp->rvp.n_rdma_seq++;
2327	qp->r_flags |= RVT_R_RDMAR_SEQ;
2328	hfi1_restart_rc(qp, qp->s_last_psn + 1, 0);
2329	if (list_empty(&qp->rspwait)) {
2330		qp->r_flags |= RVT_R_RSP_SEND;
2331		rvt_get_qp(qp);
2332		list_add_tail(&qp->rspwait, &rcd->qp_wait_list);
2333	}
2334}
2335
2336/**
2337 * rc_rcv_resp - process an incoming RC response packet
2338 * @packet: data packet information
2339 *
2340 * This is called from hfi1_rc_rcv() to process an incoming RC response
2341 * packet for the given QP.
2342 * Called at interrupt level.
2343 */
2344static void rc_rcv_resp(struct hfi1_packet *packet)
2345{
2346	struct hfi1_ctxtdata *rcd = packet->rcd;
2347	void *data = packet->payload;
2348	u32 tlen = packet->tlen;
2349	struct rvt_qp *qp = packet->qp;
2350	struct hfi1_ibport *ibp;
2351	struct ib_other_headers *ohdr = packet->ohdr;
2352	struct rvt_swqe *wqe;
2353	enum ib_wc_status status;
2354	unsigned long flags;
2355	int diff;
2356	u64 val;
2357	u32 aeth;
2358	u32 psn = ib_bth_get_psn(packet->ohdr);
2359	u32 pmtu = qp->pmtu;
2360	u16 hdrsize = packet->hlen;
2361	u8 opcode = packet->opcode;
2362	u8 pad = packet->pad;
2363	u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
2364
2365	spin_lock_irqsave(&qp->s_lock, flags);
2366	trace_hfi1_ack(qp, psn);
2367
2368	/* Ignore invalid responses. */
2369	if (cmp_psn(psn, READ_ONCE(qp->s_next_psn)) >= 0)
2370		goto ack_done;
2371
2372	/* Ignore duplicate responses. */
2373	diff = cmp_psn(psn, qp->s_last_psn);
2374	if (unlikely(diff <= 0)) {
2375		/* Update credits for "ghost" ACKs */
2376		if (diff == 0 && opcode == OP(ACKNOWLEDGE)) {
2377			aeth = be32_to_cpu(ohdr->u.aeth);
2378			if ((aeth >> IB_AETH_NAK_SHIFT) == 0)
2379				rvt_get_credit(qp, aeth);
2380		}
2381		goto ack_done;
2382	}
2383
2384	/*
2385	 * Skip everything other than the PSN we expect, if we are waiting
2386	 * for a reply to a restarted RDMA read or atomic op.
2387	 */
2388	if (qp->r_flags & RVT_R_RDMAR_SEQ) {
2389		if (cmp_psn(psn, qp->s_last_psn + 1) != 0)
2390			goto ack_done;
2391		qp->r_flags &= ~RVT_R_RDMAR_SEQ;
2392	}
2393
2394	if (unlikely(qp->s_acked == qp->s_tail))
2395		goto ack_done;
2396	wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2397	status = IB_WC_SUCCESS;
2398
2399	switch (opcode) {
2400	case OP(ACKNOWLEDGE):
2401	case OP(ATOMIC_ACKNOWLEDGE):
2402	case OP(RDMA_READ_RESPONSE_FIRST):
2403		aeth = be32_to_cpu(ohdr->u.aeth);
2404		if (opcode == OP(ATOMIC_ACKNOWLEDGE))
2405			val = ib_u64_get(&ohdr->u.at.atomic_ack_eth);
2406		else
2407			val = 0;
2408		if (!do_rc_ack(qp, aeth, psn, opcode, val, rcd) ||
2409		    opcode != OP(RDMA_READ_RESPONSE_FIRST))
2410			goto ack_done;
2411		wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2412		if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
2413			goto ack_op_err;
2414		/*
2415		 * If this is a response to a resent RDMA read, we
2416		 * have to be careful to copy the data to the right
2417		 * location.
2418		 */
2419		qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
2420						  wqe, psn, pmtu);
2421		goto read_middle;
2422
2423	case OP(RDMA_READ_RESPONSE_MIDDLE):
2424		/* no AETH, no ACK */
2425		if (unlikely(cmp_psn(psn, qp->s_last_psn + 1)))
2426			goto ack_seq_err;
2427		if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
2428			goto ack_op_err;
2429read_middle:
2430		if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
2431			goto ack_len_err;
2432		if (unlikely(pmtu >= qp->s_rdma_read_len))
2433			goto ack_len_err;
2434
2435		/*
2436		 * We got a response so update the timeout.
2437		 * 4.096 usec. * (1 << qp->timeout)
2438		 */
2439		rvt_mod_retry_timer(qp);
2440		if (qp->s_flags & RVT_S_WAIT_ACK) {
2441			qp->s_flags &= ~RVT_S_WAIT_ACK;
2442			hfi1_schedule_send(qp);
2443		}
2444
2445		if (opcode == OP(RDMA_READ_RESPONSE_MIDDLE))
2446			qp->s_retry = qp->s_retry_cnt;
2447
2448		/*
2449		 * Update the RDMA receive state but do the copy w/o
2450		 * holding the locks and blocking interrupts.
2451		 */
2452		qp->s_rdma_read_len -= pmtu;
2453		update_last_psn(qp, psn);
2454		spin_unlock_irqrestore(&qp->s_lock, flags);
2455		rvt_copy_sge(qp, &qp->s_rdma_read_sge,
2456			     data, pmtu, false, false);
2457		goto bail;
2458
2459	case OP(RDMA_READ_RESPONSE_ONLY):
2460		aeth = be32_to_cpu(ohdr->u.aeth);
2461		if (!do_rc_ack(qp, aeth, psn, opcode, 0, rcd))
2462			goto ack_done;
2463		/*
2464		 * Check that the data size is >= 0 && <= pmtu.
2465		 * Remember to account for ICRC (4).
2466		 */
2467		if (unlikely(tlen < (hdrsize + extra_bytes)))
2468			goto ack_len_err;
2469		/*
2470		 * If this is a response to a resent RDMA read, we
2471		 * have to be careful to copy the data to the right
2472		 * location.
2473		 */
2474		wqe = rvt_get_swqe_ptr(qp, qp->s_acked);
2475		qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge,
2476						  wqe, psn, pmtu);
2477		goto read_last;
2478
2479	case OP(RDMA_READ_RESPONSE_LAST):
2480		/* ACKs READ req. */
2481		if (unlikely(cmp_psn(psn, qp->s_last_psn + 1)))
2482			goto ack_seq_err;
2483		if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ))
2484			goto ack_op_err;
2485		/*
2486		 * Check that the data size is >= 1 && <= pmtu.
2487		 * Remember to account for ICRC (4).
2488		 */
2489		if (unlikely(tlen <= (hdrsize + extra_bytes)))
2490			goto ack_len_err;
2491read_last:
2492		tlen -= hdrsize + extra_bytes;
2493		if (unlikely(tlen != qp->s_rdma_read_len))
2494			goto ack_len_err;
2495		aeth = be32_to_cpu(ohdr->u.aeth);
2496		rvt_copy_sge(qp, &qp->s_rdma_read_sge,
2497			     data, tlen, false, false);
2498		WARN_ON(qp->s_rdma_read_sge.num_sge);
2499		(void)do_rc_ack(qp, aeth, psn,
2500				 OP(RDMA_READ_RESPONSE_LAST), 0, rcd);
2501		goto ack_done;
2502	}
2503
2504ack_op_err:
2505	status = IB_WC_LOC_QP_OP_ERR;
2506	goto ack_err;
2507
2508ack_seq_err:
2509	ibp = rcd_to_iport(rcd);
2510	rdma_seq_err(qp, ibp, psn, rcd);
2511	goto ack_done;
2512
2513ack_len_err:
2514	status = IB_WC_LOC_LEN_ERR;
2515ack_err:
2516	if (qp->s_last == qp->s_acked) {
2517		rvt_send_complete(qp, wqe, status);
2518		rvt_error_qp(qp, IB_WC_WR_FLUSH_ERR);
2519	}
2520ack_done:
2521	spin_unlock_irqrestore(&qp->s_lock, flags);
2522bail:
2523	return;
2524}
2525
2526static inline void rc_cancel_ack(struct rvt_qp *qp)
2527{
2528	qp->r_adefered = 0;
2529	if (list_empty(&qp->rspwait))
2530		return;
2531	list_del_init(&qp->rspwait);
2532	qp->r_flags &= ~RVT_R_RSP_NAK;
2533	rvt_put_qp(qp);
2534}
2535
2536/**
2537 * rc_rcv_error - process an incoming duplicate or error RC packet
2538 * @ohdr: the other headers for this packet
2539 * @data: the packet data
2540 * @qp: the QP for this packet
2541 * @opcode: the opcode for this packet
2542 * @psn: the packet sequence number for this packet
2543 * @diff: the difference between the PSN and the expected PSN
2544 *
2545 * This is called from hfi1_rc_rcv() to process an unexpected
2546 * incoming RC packet for the given QP.
2547 * Called at interrupt level.
2548 * Return 1 if no more processing is needed; otherwise return 0 to
2549 * schedule a response to be sent.
2550 */
2551static noinline int rc_rcv_error(struct ib_other_headers *ohdr, void *data,
2552				 struct rvt_qp *qp, u32 opcode, u32 psn,
2553				 int diff, struct hfi1_ctxtdata *rcd)
2554{
2555	struct hfi1_ibport *ibp = rcd_to_iport(rcd);
2556	struct rvt_ack_entry *e;
2557	unsigned long flags;
2558	u8 prev;
2559	u8 mra; /* most recent ACK */
2560	bool old_req;
2561
2562	trace_hfi1_rcv_error(qp, psn);
2563	if (diff > 0) {
2564		/*
2565		 * Packet sequence error.
2566		 * A NAK will ACK earlier sends and RDMA writes.
2567		 * Don't queue the NAK if we already sent one.
2568		 */
2569		if (!qp->r_nak_state) {
2570			ibp->rvp.n_rc_seqnak++;
2571			qp->r_nak_state = IB_NAK_PSN_ERROR;
2572			/* Use the expected PSN. */
2573			qp->r_ack_psn = qp->r_psn;
2574			/*
2575			 * Wait to send the sequence NAK until all packets
2576			 * in the receive queue have been processed.
2577			 * Otherwise, we end up propagating congestion.
2578			 */
2579			rc_defered_ack(rcd, qp);
2580		}
2581		goto done;
2582	}
2583
2584	/*
2585	 * Handle a duplicate request.  Don't re-execute SEND, RDMA
2586	 * write or atomic op.  Don't NAK errors, just silently drop
2587	 * the duplicate request.  Note that r_sge, r_len, and
2588	 * r_rcv_len may be in use so don't modify them.
2589	 *
2590	 * We are supposed to ACK the earliest duplicate PSN but we
2591	 * can coalesce an outstanding duplicate ACK.  We have to
2592	 * send the earliest so that RDMA reads can be restarted at
2593	 * the requester's expected PSN.
2594	 *
2595	 * First, find where this duplicate PSN falls within the
2596	 * ACKs previously sent.
2597	 * old_req is true if there is an older response that is scheduled
2598	 * to be sent before sending this one.
2599	 */
2600	e = NULL;
2601	old_req = true;
2602	ibp->rvp.n_rc_dupreq++;
2603
2604	spin_lock_irqsave(&qp->s_lock, flags);
2605
2606	e = find_prev_entry(qp, psn, &prev, &mra, &old_req);
2607
2608	switch (opcode) {
2609	case OP(RDMA_READ_REQUEST): {
2610		struct ib_reth *reth;
2611		u32 offset;
2612		u32 len;
2613
2614		/*
2615		 * If we didn't find the RDMA read request in the ack queue,
2616		 * we can ignore this request.
2617		 */
2618		if (!e || e->opcode != OP(RDMA_READ_REQUEST))
2619			goto unlock_done;
2620		/* RETH comes after BTH */
2621		reth = &ohdr->u.rc.reth;
2622		/*
2623		 * Address range must be a subset of the original
2624		 * request and start on pmtu boundaries.
2625		 * We reuse the old ack_queue slot since the requester
2626		 * should not back up and request an earlier PSN for the
2627		 * same request.
2628		 */
2629		offset = delta_psn(psn, e->psn) * qp->pmtu;
2630		len = be32_to_cpu(reth->length);
2631		if (unlikely(offset + len != e->rdma_sge.sge_length))
2632			goto unlock_done;
2633		release_rdma_sge_mr(e);
2634		if (len != 0) {
2635			u32 rkey = be32_to_cpu(reth->rkey);
2636			u64 vaddr = get_ib_reth_vaddr(reth);
2637			int ok;
2638
2639			ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey,
2640					 IB_ACCESS_REMOTE_READ);
2641			if (unlikely(!ok))
2642				goto unlock_done;
2643		} else {
2644			e->rdma_sge.vaddr = NULL;
2645			e->rdma_sge.length = 0;
2646			e->rdma_sge.sge_length = 0;
2647		}
2648		e->psn = psn;
2649		if (old_req)
2650			goto unlock_done;
2651		if (qp->s_acked_ack_queue == qp->s_tail_ack_queue)
2652			qp->s_acked_ack_queue = prev;
2653		qp->s_tail_ack_queue = prev;
2654		break;
2655	}
2656
2657	case OP(COMPARE_SWAP):
2658	case OP(FETCH_ADD): {
2659		/*
2660		 * If we didn't find the atomic request in the ack queue
2661		 * or the send engine is already backed up to send an
2662		 * earlier entry, we can ignore this request.
2663		 */
2664		if (!e || e->opcode != (u8)opcode || old_req)
2665			goto unlock_done;
2666		if (qp->s_tail_ack_queue == qp->s_acked_ack_queue)
2667			qp->s_acked_ack_queue = prev;
2668		qp->s_tail_ack_queue = prev;
2669		break;
2670	}
2671
2672	default:
2673		/*
2674		 * Ignore this operation if it doesn't request an ACK
2675		 * or an earlier RDMA read or atomic is going to be resent.
2676		 */
2677		if (!(psn & IB_BTH_REQ_ACK) || old_req)
2678			goto unlock_done;
2679		/*
2680		 * Resend the most recent ACK if this request is
2681		 * after all the previous RDMA reads and atomics.
2682		 */
2683		if (mra == qp->r_head_ack_queue) {
2684			spin_unlock_irqrestore(&qp->s_lock, flags);
2685			qp->r_nak_state = 0;
2686			qp->r_ack_psn = qp->r_psn - 1;
2687			goto send_ack;
2688		}
2689
2690		/*
2691		 * Resend the RDMA read or atomic op which
2692		 * ACKs this duplicate request.
2693		 */
2694		if (qp->s_tail_ack_queue == qp->s_acked_ack_queue)
2695			qp->s_acked_ack_queue = mra;
2696		qp->s_tail_ack_queue = mra;
2697		break;
2698	}
2699	qp->s_ack_state = OP(ACKNOWLEDGE);
2700	qp->s_flags |= RVT_S_RESP_PENDING;
2701	qp->r_nak_state = 0;
2702	hfi1_schedule_send(qp);
2703
2704unlock_done:
2705	spin_unlock_irqrestore(&qp->s_lock, flags);
2706done:
2707	return 1;
2708
2709send_ack:
2710	return 0;
2711}
2712
2713static void log_cca_event(struct hfi1_pportdata *ppd, u8 sl, u32 rlid,
2714			  u32 lqpn, u32 rqpn, u8 svc_type)
2715{
2716	struct opa_hfi1_cong_log_event_internal *cc_event;
2717	unsigned long flags;
2718
2719	if (sl >= OPA_MAX_SLS)
2720		return;
2721
2722	spin_lock_irqsave(&ppd->cc_log_lock, flags);
2723
2724	ppd->threshold_cong_event_map[sl / 8] |= 1 << (sl % 8);
2725	ppd->threshold_event_counter++;
2726
2727	cc_event = &ppd->cc_events[ppd->cc_log_idx++];
2728	if (ppd->cc_log_idx == OPA_CONG_LOG_ELEMS)
2729		ppd->cc_log_idx = 0;
2730	cc_event->lqpn = lqpn & RVT_QPN_MASK;
2731	cc_event->rqpn = rqpn & RVT_QPN_MASK;
2732	cc_event->sl = sl;
2733	cc_event->svc_type = svc_type;
2734	cc_event->rlid = rlid;
2735	/* keep timestamp in units of 1.024 usec */
2736	cc_event->timestamp = ktime_get_ns() / 1024;
2737
2738	spin_unlock_irqrestore(&ppd->cc_log_lock, flags);
2739}
2740
2741void process_becn(struct hfi1_pportdata *ppd, u8 sl, u32 rlid, u32 lqpn,
2742		  u32 rqpn, u8 svc_type)
2743{
2744	struct cca_timer *cca_timer;
2745	u16 ccti, ccti_incr, ccti_timer, ccti_limit;
2746	u8 trigger_threshold;
2747	struct cc_state *cc_state;
2748	unsigned long flags;
2749
2750	if (sl >= OPA_MAX_SLS)
2751		return;
2752
2753	cc_state = get_cc_state(ppd);
2754
2755	if (!cc_state)
2756		return;
2757
2758	/*
2759	 * 1) increase CCTI (for this SL)
2760	 * 2) select IPG (i.e., call set_link_ipg())
2761	 * 3) start timer
2762	 */
2763	ccti_limit = cc_state->cct.ccti_limit;
2764	ccti_incr = cc_state->cong_setting.entries[sl].ccti_increase;
2765	ccti_timer = cc_state->cong_setting.entries[sl].ccti_timer;
2766	trigger_threshold =
2767		cc_state->cong_setting.entries[sl].trigger_threshold;
2768
2769	spin_lock_irqsave(&ppd->cca_timer_lock, flags);
2770
2771	cca_timer = &ppd->cca_timer[sl];
2772	if (cca_timer->ccti < ccti_limit) {
2773		if (cca_timer->ccti + ccti_incr <= ccti_limit)
2774			cca_timer->ccti += ccti_incr;
2775		else
2776			cca_timer->ccti = ccti_limit;
2777		set_link_ipg(ppd);
2778	}
2779
2780	ccti = cca_timer->ccti;
2781
2782	if (!hrtimer_active(&cca_timer->hrtimer)) {
2783		/* ccti_timer is in units of 1.024 usec */
2784		unsigned long nsec = 1024 * ccti_timer;
2785
2786		hrtimer_start(&cca_timer->hrtimer, ns_to_ktime(nsec),
2787			      HRTIMER_MODE_REL_PINNED);
2788	}
2789
2790	spin_unlock_irqrestore(&ppd->cca_timer_lock, flags);
2791
2792	if ((trigger_threshold != 0) && (ccti >= trigger_threshold))
2793		log_cca_event(ppd, sl, rlid, lqpn, rqpn, svc_type);
2794}
2795
2796/**
2797 * hfi1_rc_rcv - process an incoming RC packet
2798 * @packet: data packet information
2799 *
2800 * This is called from qp_rcv() to process an incoming RC packet
2801 * for the given QP.
2802 * May be called at interrupt level.
2803 */
2804void hfi1_rc_rcv(struct hfi1_packet *packet)
2805{
2806	struct hfi1_ctxtdata *rcd = packet->rcd;
2807	void *data = packet->payload;
2808	u32 tlen = packet->tlen;
2809	struct rvt_qp *qp = packet->qp;
2810	struct hfi1_qp_priv *qpriv = qp->priv;
2811	struct hfi1_ibport *ibp = rcd_to_iport(rcd);
2812	struct ib_other_headers *ohdr = packet->ohdr;
2813	u32 opcode = packet->opcode;
2814	u32 hdrsize = packet->hlen;
2815	u32 psn = ib_bth_get_psn(packet->ohdr);
2816	u32 pad = packet->pad;
2817	struct ib_wc wc;
2818	u32 pmtu = qp->pmtu;
2819	int diff;
2820	struct ib_reth *reth;
2821	unsigned long flags;
2822	int ret;
2823	bool copy_last = false, fecn;
2824	u32 rkey;
2825	u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);
2826
2827	lockdep_assert_held(&qp->r_lock);
2828
2829	if (hfi1_ruc_check_hdr(ibp, packet))
2830		return;
2831
2832	fecn = process_ecn(qp, packet);
2833	opfn_trigger_conn_request(qp, be32_to_cpu(ohdr->bth[1]));
2834
2835	/*
2836	 * Process responses (ACKs) before anything else.  Note that the
2837	 * packet sequence number will be for something in the send work
2838	 * queue rather than the expected receive packet sequence number.
2839	 * In other words, this QP is the requester.
2840	 */
2841	if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) &&
2842	    opcode <= OP(ATOMIC_ACKNOWLEDGE)) {
2843		rc_rcv_resp(packet);
2844		return;
2845	}
2846
2847	/* Compute 24 bits worth of difference. */
2848	diff = delta_psn(psn, qp->r_psn);
2849	if (unlikely(diff)) {
2850		if (rc_rcv_error(ohdr, data, qp, opcode, psn, diff, rcd))
2851			return;
2852		goto send_ack;
2853	}
2854
2855	/* Check for opcode sequence errors. */
2856	switch (qp->r_state) {
2857	case OP(SEND_FIRST):
2858	case OP(SEND_MIDDLE):
2859		if (opcode == OP(SEND_MIDDLE) ||
2860		    opcode == OP(SEND_LAST) ||
2861		    opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
2862		    opcode == OP(SEND_LAST_WITH_INVALIDATE))
2863			break;
2864		goto nack_inv;
2865
2866	case OP(RDMA_WRITE_FIRST):
2867	case OP(RDMA_WRITE_MIDDLE):
2868		if (opcode == OP(RDMA_WRITE_MIDDLE) ||
2869		    opcode == OP(RDMA_WRITE_LAST) ||
2870		    opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
2871			break;
2872		goto nack_inv;
2873
2874	default:
2875		if (opcode == OP(SEND_MIDDLE) ||
2876		    opcode == OP(SEND_LAST) ||
2877		    opcode == OP(SEND_LAST_WITH_IMMEDIATE) ||
2878		    opcode == OP(SEND_LAST_WITH_INVALIDATE) ||
2879		    opcode == OP(RDMA_WRITE_MIDDLE) ||
2880		    opcode == OP(RDMA_WRITE_LAST) ||
2881		    opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE))
2882			goto nack_inv;
2883		/*
2884		 * Note that it is up to the requester to not send a new
2885		 * RDMA read or atomic operation before receiving an ACK
2886		 * for the previous operation.
2887		 */
2888		break;
2889	}
2890
2891	if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST))
2892		rvt_comm_est(qp);
2893
2894	/* OK, process the packet. */
2895	switch (opcode) {
2896	case OP(SEND_FIRST):
2897		ret = rvt_get_rwqe(qp, false);
2898		if (ret < 0)
2899			goto nack_op_err;
2900		if (!ret)
2901			goto rnr_nak;
2902		qp->r_rcv_len = 0;
2903		fallthrough;
2904	case OP(SEND_MIDDLE):
2905	case OP(RDMA_WRITE_MIDDLE):
2906send_middle:
2907		/* Check for invalid length PMTU or posted rwqe len. */
2908		/*
2909		 * There will be no padding for 9B packet but 16B packets
2910		 * will come in with some padding since we always add
2911		 * CRC and LT bytes which will need to be flit aligned
2912		 */
2913		if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
2914			goto nack_inv;
2915		qp->r_rcv_len += pmtu;
2916		if (unlikely(qp->r_rcv_len > qp->r_len))
2917			goto nack_inv;
2918		rvt_copy_sge(qp, &qp->r_sge, data, pmtu, true, false);
2919		break;
2920
2921	case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
2922		/* consume RWQE */
2923		ret = rvt_get_rwqe(qp, true);
2924		if (ret < 0)
2925			goto nack_op_err;
2926		if (!ret)
2927			goto rnr_nak;
2928		goto send_last_imm;
2929
2930	case OP(SEND_ONLY):
2931	case OP(SEND_ONLY_WITH_IMMEDIATE):
2932	case OP(SEND_ONLY_WITH_INVALIDATE):
2933		ret = rvt_get_rwqe(qp, false);
2934		if (ret < 0)
2935			goto nack_op_err;
2936		if (!ret)
2937			goto rnr_nak;
2938		qp->r_rcv_len = 0;
2939		if (opcode == OP(SEND_ONLY))
2940			goto no_immediate_data;
2941		if (opcode == OP(SEND_ONLY_WITH_INVALIDATE))
2942			goto send_last_inv;
2943		fallthrough;	/* for SEND_ONLY_WITH_IMMEDIATE */
2944	case OP(SEND_LAST_WITH_IMMEDIATE):
2945send_last_imm:
2946		wc.ex.imm_data = ohdr->u.imm_data;
2947		wc.wc_flags = IB_WC_WITH_IMM;
2948		goto send_last;
2949	case OP(SEND_LAST_WITH_INVALIDATE):
2950send_last_inv:
2951		rkey = be32_to_cpu(ohdr->u.ieth);
2952		if (rvt_invalidate_rkey(qp, rkey))
2953			goto no_immediate_data;
2954		wc.ex.invalidate_rkey = rkey;
2955		wc.wc_flags = IB_WC_WITH_INVALIDATE;
2956		goto send_last;
2957	case OP(RDMA_WRITE_LAST):
2958		copy_last = rvt_is_user_qp(qp);
2959		fallthrough;
2960	case OP(SEND_LAST):
2961no_immediate_data:
2962		wc.wc_flags = 0;
2963		wc.ex.imm_data = 0;
2964send_last:
2965		/* Check for invalid length. */
2966		/* LAST len should be >= 1 */
2967		if (unlikely(tlen < (hdrsize + extra_bytes)))
2968			goto nack_inv;
2969		/* Don't count the CRC(and padding and LT byte for 16B). */
2970		tlen -= (hdrsize + extra_bytes);
2971		wc.byte_len = tlen + qp->r_rcv_len;
2972		if (unlikely(wc.byte_len > qp->r_len))
2973			goto nack_inv;
2974		rvt_copy_sge(qp, &qp->r_sge, data, tlen, true, copy_last);
2975		rvt_put_ss(&qp->r_sge);
2976		qp->r_msn++;
2977		if (!__test_and_clear_bit(RVT_R_WRID_VALID, &qp->r_aflags))
2978			break;
2979		wc.wr_id = qp->r_wr_id;
2980		wc.status = IB_WC_SUCCESS;
2981		if (opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE) ||
2982		    opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
2983			wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
2984		else
2985			wc.opcode = IB_WC_RECV;
2986		wc.qp = &qp->ibqp;
2987		wc.src_qp = qp->remote_qpn;
2988		wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
2989		/*
2990		 * It seems that IB mandates the presence of an SL in a
2991		 * work completion only for the UD transport (see section
2992		 * 11.4.2 of IBTA Vol. 1).
2993		 *
2994		 * However, the way the SL is chosen below is consistent
2995		 * with the way that IB/qib works and is trying avoid
2996		 * introducing incompatibilities.
2997		 *
2998		 * See also OPA Vol. 1, section 9.7.6, and table 9-17.
2999		 */
3000		wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
3001		/* zero fields that are N/A */
3002		wc.vendor_err = 0;
3003		wc.pkey_index = 0;
3004		wc.dlid_path_bits = 0;
3005		wc.port_num = 0;
3006		/* Signal completion event if the solicited bit is set. */
3007		rvt_recv_cq(qp, &wc, ib_bth_is_solicited(ohdr));
3008		break;
3009
3010	case OP(RDMA_WRITE_ONLY):
3011		copy_last = rvt_is_user_qp(qp);
3012		fallthrough;
3013	case OP(RDMA_WRITE_FIRST):
3014	case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
3015		if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
3016			goto nack_inv;
3017		/* consume RWQE */
3018		reth = &ohdr->u.rc.reth;
3019		qp->r_len = be32_to_cpu(reth->length);
3020		qp->r_rcv_len = 0;
3021		qp->r_sge.sg_list = NULL;
3022		if (qp->r_len != 0) {
3023			u32 rkey = be32_to_cpu(reth->rkey);
3024			u64 vaddr = get_ib_reth_vaddr(reth);
3025			int ok;
3026
3027			/* Check rkey & NAK */
3028			ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len, vaddr,
3029					 rkey, IB_ACCESS_REMOTE_WRITE);
3030			if (unlikely(!ok))
3031				goto nack_acc;
3032			qp->r_sge.num_sge = 1;
3033		} else {
3034			qp->r_sge.num_sge = 0;
3035			qp->r_sge.sge.mr = NULL;
3036			qp->r_sge.sge.vaddr = NULL;
3037			qp->r_sge.sge.length = 0;
3038			qp->r_sge.sge.sge_length = 0;
3039		}
3040		if (opcode == OP(RDMA_WRITE_FIRST))
3041			goto send_middle;
3042		else if (opcode == OP(RDMA_WRITE_ONLY))
3043			goto no_immediate_data;
3044		ret = rvt_get_rwqe(qp, true);
3045		if (ret < 0)
3046			goto nack_op_err;
3047		if (!ret) {
3048			/* peer will send again */
3049			rvt_put_ss(&qp->r_sge);
3050			goto rnr_nak;
3051		}
3052		wc.ex.imm_data = ohdr->u.rc.imm_data;
3053		wc.wc_flags = IB_WC_WITH_IMM;
3054		goto send_last;
3055
3056	case OP(RDMA_READ_REQUEST): {
3057		struct rvt_ack_entry *e;
3058		u32 len;
3059		u8 next;
3060
3061		if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
3062			goto nack_inv;
3063		next = qp->r_head_ack_queue + 1;
3064		/* s_ack_queue is size rvt_size_atomic()+1 so use > not >= */
3065		if (next > rvt_size_atomic(ib_to_rvt(qp->ibqp.device)))
3066			next = 0;
3067		spin_lock_irqsave(&qp->s_lock, flags);
3068		if (unlikely(next == qp->s_acked_ack_queue)) {
3069			if (!qp->s_ack_queue[next].sent)
3070				goto nack_inv_unlck;
3071			update_ack_queue(qp, next);
3072		}
3073		e = &qp->s_ack_queue[qp->r_head_ack_queue];
3074		release_rdma_sge_mr(e);
3075		reth = &ohdr->u.rc.reth;
3076		len = be32_to_cpu(reth->length);
3077		if (len) {
3078			u32 rkey = be32_to_cpu(reth->rkey);
3079			u64 vaddr = get_ib_reth_vaddr(reth);
3080			int ok;
3081
3082			/* Check rkey & NAK */
3083			ok = rvt_rkey_ok(qp, &e->rdma_sge, len, vaddr,
3084					 rkey, IB_ACCESS_REMOTE_READ);
3085			if (unlikely(!ok))
3086				goto nack_acc_unlck;
3087			/*
3088			 * Update the next expected PSN.  We add 1 later
3089			 * below, so only add the remainder here.
3090			 */
3091			qp->r_psn += rvt_div_mtu(qp, len - 1);
3092		} else {
3093			e->rdma_sge.mr = NULL;
3094			e->rdma_sge.vaddr = NULL;
3095			e->rdma_sge.length = 0;
3096			e->rdma_sge.sge_length = 0;
3097		}
3098		e->opcode = opcode;
3099		e->sent = 0;
3100		e->psn = psn;
3101		e->lpsn = qp->r_psn;
3102		/*
3103		 * We need to increment the MSN here instead of when we
3104		 * finish sending the result since a duplicate request would
3105		 * increment it more than once.
3106		 */
3107		qp->r_msn++;
3108		qp->r_psn++;
3109		qp->r_state = opcode;
3110		qp->r_nak_state = 0;
3111		qp->r_head_ack_queue = next;
3112		qpriv->r_tid_alloc = qp->r_head_ack_queue;
3113
3114		/* Schedule the send engine. */
3115		qp->s_flags |= RVT_S_RESP_PENDING;
3116		if (fecn)
3117			qp->s_flags |= RVT_S_ECN;
3118		hfi1_schedule_send(qp);
3119
3120		spin_unlock_irqrestore(&qp->s_lock, flags);
3121		return;
3122	}
3123
3124	case OP(COMPARE_SWAP):
3125	case OP(FETCH_ADD): {
3126		struct ib_atomic_eth *ateth = &ohdr->u.atomic_eth;
3127		u64 vaddr = get_ib_ateth_vaddr(ateth);
3128		bool opfn = opcode == OP(COMPARE_SWAP) &&
3129			vaddr == HFI1_VERBS_E_ATOMIC_VADDR;
3130		struct rvt_ack_entry *e;
3131		atomic64_t *maddr;
3132		u64 sdata;
3133		u32 rkey;
3134		u8 next;
3135
3136		if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC) &&
3137			     !opfn))
3138			goto nack_inv;
3139		next = qp->r_head_ack_queue + 1;
3140		if (next > rvt_size_atomic(ib_to_rvt(qp->ibqp.device)))
3141			next = 0;
3142		spin_lock_irqsave(&qp->s_lock, flags);
3143		if (unlikely(next == qp->s_acked_ack_queue)) {
3144			if (!qp->s_ack_queue[next].sent)
3145				goto nack_inv_unlck;
3146			update_ack_queue(qp, next);
3147		}
3148		e = &qp->s_ack_queue[qp->r_head_ack_queue];
3149		release_rdma_sge_mr(e);
3150		/* Process OPFN special virtual address */
3151		if (opfn) {
3152			opfn_conn_response(qp, e, ateth);
3153			goto ack;
3154		}
3155		if (unlikely(vaddr & (sizeof(u64) - 1)))
3156			goto nack_inv_unlck;
3157		rkey = be32_to_cpu(ateth->rkey);
3158		/* Check rkey & NAK */
3159		if (unlikely(!rvt_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
3160					  vaddr, rkey,
3161					  IB_ACCESS_REMOTE_ATOMIC)))
3162			goto nack_acc_unlck;
3163		/* Perform atomic OP and save result. */
3164		maddr = (atomic64_t *)qp->r_sge.sge.vaddr;
3165		sdata = get_ib_ateth_swap(ateth);
3166		e->atomic_data = (opcode == OP(FETCH_ADD)) ?
3167			(u64)atomic64_add_return(sdata, maddr) - sdata :
3168			(u64)cmpxchg((u64 *)qp->r_sge.sge.vaddr,
3169				      get_ib_ateth_compare(ateth),
3170				      sdata);
3171		rvt_put_mr(qp->r_sge.sge.mr);
3172		qp->r_sge.num_sge = 0;
3173ack:
3174		e->opcode = opcode;
3175		e->sent = 0;
3176		e->psn = psn;
3177		e->lpsn = psn;
3178		qp->r_msn++;
3179		qp->r_psn++;
3180		qp->r_state = opcode;
3181		qp->r_nak_state = 0;
3182		qp->r_head_ack_queue = next;
3183		qpriv->r_tid_alloc = qp->r_head_ack_queue;
3184
3185		/* Schedule the send engine. */
3186		qp->s_flags |= RVT_S_RESP_PENDING;
3187		if (fecn)
3188			qp->s_flags |= RVT_S_ECN;
3189		hfi1_schedule_send(qp);
3190
3191		spin_unlock_irqrestore(&qp->s_lock, flags);
3192		return;
3193	}
3194
3195	default:
3196		/* NAK unknown opcodes. */
3197		goto nack_inv;
3198	}
3199	qp->r_psn++;
3200	qp->r_state = opcode;
3201	qp->r_ack_psn = psn;
3202	qp->r_nak_state = 0;
3203	/* Send an ACK if requested or required. */
3204	if (psn & IB_BTH_REQ_ACK || fecn) {
3205		if (packet->numpkt == 0 || fecn ||
3206		    qp->r_adefered >= HFI1_PSN_CREDIT) {
3207			rc_cancel_ack(qp);
3208			goto send_ack;
3209		}
3210		qp->r_adefered++;
3211		rc_defered_ack(rcd, qp);
3212	}
3213	return;
3214
3215rnr_nak:
3216	qp->r_nak_state = qp->r_min_rnr_timer | IB_RNR_NAK;
3217	qp->r_ack_psn = qp->r_psn;
3218	/* Queue RNR NAK for later */
3219	rc_defered_ack(rcd, qp);
3220	return;
3221
3222nack_op_err:
3223	rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
3224	qp->r_nak_state = IB_NAK_REMOTE_OPERATIONAL_ERROR;
3225	qp->r_ack_psn = qp->r_psn;
3226	/* Queue NAK for later */
3227	rc_defered_ack(rcd, qp);
3228	return;
3229
3230nack_inv_unlck:
3231	spin_unlock_irqrestore(&qp->s_lock, flags);
3232nack_inv:
3233	rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
3234	qp->r_nak_state = IB_NAK_INVALID_REQUEST;
3235	qp->r_ack_psn = qp->r_psn;
3236	/* Queue NAK for later */
3237	rc_defered_ack(rcd, qp);
3238	return;
3239
3240nack_acc_unlck:
3241	spin_unlock_irqrestore(&qp->s_lock, flags);
3242nack_acc:
3243	rvt_rc_error(qp, IB_WC_LOC_PROT_ERR);
3244	qp->r_nak_state = IB_NAK_REMOTE_ACCESS_ERROR;
3245	qp->r_ack_psn = qp->r_psn;
3246send_ack:
3247	hfi1_send_rc_ack(packet, fecn);
3248}
3249
3250void hfi1_rc_hdrerr(
3251	struct hfi1_ctxtdata *rcd,
3252	struct hfi1_packet *packet,
3253	struct rvt_qp *qp)
3254{
3255	struct hfi1_ibport *ibp = rcd_to_iport(rcd);
3256	int diff;
3257	u32 opcode;
3258	u32 psn;
3259
3260	if (hfi1_ruc_check_hdr(ibp, packet))
3261		return;
3262
3263	psn = ib_bth_get_psn(packet->ohdr);
3264	opcode = ib_bth_get_opcode(packet->ohdr);
3265
3266	/* Only deal with RDMA Writes for now */
3267	if (opcode < IB_OPCODE_RC_RDMA_READ_RESPONSE_FIRST) {
3268		diff = delta_psn(psn, qp->r_psn);
3269		if (!qp->r_nak_state && diff >= 0) {
3270			ibp->rvp.n_rc_seqnak++;
3271			qp->r_nak_state = IB_NAK_PSN_ERROR;
3272			/* Use the expected PSN. */
3273			qp->r_ack_psn = qp->r_psn;
3274			/*
3275			 * Wait to send the sequence
3276			 * NAK until all packets
3277			 * in the receive queue have
3278			 * been processed.
3279			 * Otherwise, we end up
3280			 * propagating congestion.
3281			 */
3282			rc_defered_ack(rcd, qp);
3283		} /* Out of sequence NAK */
3284	} /* QP Request NAKs */
3285}
3286