summaryrefslogtreecommitdiff
path: root/drivers/infiniband/hw/hfi1/ipoib_tx.c
blob: d6bbdb8fcb50a2945fa010c6bb338fad18fb4df1 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
/*
 * Copyright(c) 2020 Intel Corporation.
 *
 */

/*
 * This file contains HFI1 support for IPOIB SDMA functionality
 */

#include <linux/log2.h>
#include <linux/circ_buf.h>

#include "sdma.h"
#include "verbs.h"
#include "trace_ibhdrs.h"
#include "ipoib.h"
#include "trace_tx.h"

/* Add a convenience helper */
#define CIRC_ADD(val, add, size) (((val) + (add)) & ((size) - 1))
#define CIRC_NEXT(val, size) CIRC_ADD(val, 1, size)
#define CIRC_PREV(val, size) CIRC_ADD(val, -1, size)

struct ipoib_txparms {
	struct hfi1_devdata        *dd;
	struct rdma_ah_attr        *ah_attr;
	struct hfi1_ibport         *ibp;
	struct hfi1_ipoib_txq      *txq;
	union hfi1_ipoib_flow       flow;
	u32                         dqpn;
	u8                          hdr_dwords;
	u8                          entropy;
};

static struct ipoib_txreq *
hfi1_txreq_from_idx(struct hfi1_ipoib_circ_buf *r, u32 idx)
{
	return (struct ipoib_txreq *)(r->items + (idx << r->shift));
}

static u32 hfi1_ipoib_txreqs(const u64 sent, const u64 completed)
{
	return sent - completed;
}

static u64 hfi1_ipoib_used(struct hfi1_ipoib_txq *txq)
{
	return hfi1_ipoib_txreqs(txq->tx_ring.sent_txreqs,
				 txq->tx_ring.complete_txreqs);
}

static void hfi1_ipoib_stop_txq(struct hfi1_ipoib_txq *txq)
{
	trace_hfi1_txq_stop(txq);
	if (atomic_inc_return(&txq->tx_ring.stops) == 1)
		netif_stop_subqueue(txq->priv->netdev, txq->q_idx);
}

static void hfi1_ipoib_wake_txq(struct hfi1_ipoib_txq *txq)
{
	trace_hfi1_txq_wake(txq);
	if (atomic_dec_and_test(&txq->tx_ring.stops))
		netif_wake_subqueue(txq->priv->netdev, txq->q_idx);
}

static uint hfi1_ipoib_ring_hwat(struct hfi1_ipoib_txq *txq)
{
	return min_t(uint, txq->priv->netdev->tx_queue_len,
		     txq->tx_ring.max_items - 1);
}

static uint hfi1_ipoib_ring_lwat(struct hfi1_ipoib_txq *txq)
{
	return min_t(uint, txq->priv->netdev->tx_queue_len,
		     txq->tx_ring.max_items) >> 1;
}

static void hfi1_ipoib_check_queue_depth(struct hfi1_ipoib_txq *txq)
{
	++txq->tx_ring.sent_txreqs;
	if (hfi1_ipoib_used(txq) >= hfi1_ipoib_ring_hwat(txq) &&
	    !atomic_xchg(&txq->tx_ring.ring_full, 1)) {
		trace_hfi1_txq_full(txq);
		hfi1_ipoib_stop_txq(txq);
	}
}

static void hfi1_ipoib_check_queue_stopped(struct hfi1_ipoib_txq *txq)
{
	struct net_device *dev = txq->priv->netdev;

	/* If shutting down just return as queue state is irrelevant */
	if (unlikely(dev->reg_state != NETREG_REGISTERED))
		return;

	/*
	 * When the queue has been drained to less than half full it will be
	 * restarted.
	 * The size of the txreq ring is fixed at initialization.
	 * The tx queue len can be adjusted upward while the interface is
	 * running.
	 * The tx queue len can be large enough to overflow the txreq_ring.
	 * Use the minimum of the current tx_queue_len or the rings max txreqs
	 * to protect against ring overflow.
	 */
	if (hfi1_ipoib_used(txq) < hfi1_ipoib_ring_lwat(txq) &&
	    atomic_xchg(&txq->tx_ring.ring_full, 0)) {
		trace_hfi1_txq_xmit_unstopped(txq);
		hfi1_ipoib_wake_txq(txq);
	}
}

static void hfi1_ipoib_free_tx(struct ipoib_txreq *tx, int budget)
{
	struct hfi1_ipoib_dev_priv *priv = tx->txq->priv;

	if (likely(!tx->sdma_status)) {
		dev_sw_netstats_tx_add(priv->netdev, 1, tx->skb->len);
	} else {
		++priv->netdev->stats.tx_errors;
		dd_dev_warn(priv->dd,
			    "%s: Status = 0x%x pbc 0x%llx txq = %d sde = %d\n",
			    __func__, tx->sdma_status,
			    le64_to_cpu(tx->sdma_hdr->pbc), tx->txq->q_idx,
			    tx->txq->sde->this_idx);
	}

	napi_consume_skb(tx->skb, budget);
	tx->skb = NULL;
	sdma_txclean(priv->dd, &tx->txreq);
}

static void hfi1_ipoib_drain_tx_ring(struct hfi1_ipoib_txq *txq)
{
	struct hfi1_ipoib_circ_buf *tx_ring = &txq->tx_ring;
	int i;
	struct ipoib_txreq *tx;

	for (i = 0; i < tx_ring->max_items; i++) {
		tx = hfi1_txreq_from_idx(tx_ring, i);
		tx->complete = 0;
		dev_kfree_skb_any(tx->skb);
		tx->skb = NULL;
		sdma_txclean(txq->priv->dd, &tx->txreq);
	}
	tx_ring->head = 0;
	tx_ring->tail = 0;
	tx_ring->complete_txreqs = 0;
	tx_ring->sent_txreqs = 0;
	tx_ring->avail = hfi1_ipoib_ring_hwat(txq);
}

static int hfi1_ipoib_poll_tx_ring(struct napi_struct *napi, int budget)
{
	struct hfi1_ipoib_txq *txq =
		container_of(napi, struct hfi1_ipoib_txq, napi);
	struct hfi1_ipoib_circ_buf *tx_ring = &txq->tx_ring;
	u32 head = tx_ring->head;
	u32 max_tx = tx_ring->max_items;
	int work_done;
	struct ipoib_txreq *tx =  hfi1_txreq_from_idx(tx_ring, head);

	trace_hfi1_txq_poll(txq);
	for (work_done = 0; work_done < budget; work_done++) {
		/* See hfi1_ipoib_sdma_complete() */
		if (!smp_load_acquire(&tx->complete))
			break;
		tx->complete = 0;
		trace_hfi1_tx_produce(tx, head);
		hfi1_ipoib_free_tx(tx, budget);
		head = CIRC_NEXT(head, max_tx);
		tx =  hfi1_txreq_from_idx(tx_ring, head);
	}
	tx_ring->complete_txreqs += work_done;

	/* Finished freeing tx items so store the head value. */
	smp_store_release(&tx_ring->head, head);

	hfi1_ipoib_check_queue_stopped(txq);

	if (work_done < budget)
		napi_complete_done(napi, work_done);

	return work_done;
}

static void hfi1_ipoib_sdma_complete(struct sdma_txreq *txreq, int status)
{
	struct ipoib_txreq *tx = container_of(txreq, struct ipoib_txreq, txreq);

	trace_hfi1_txq_complete(tx->txq);
	tx->sdma_status = status;
	/* see hfi1_ipoib_poll_tx_ring */
	smp_store_release(&tx->complete, 1);
	napi_schedule_irqoff(&tx->txq->napi);
}

static int hfi1_ipoib_build_ulp_payload(struct ipoib_txreq *tx,
					struct ipoib_txparms *txp)
{
	struct hfi1_devdata *dd = txp->dd;
	struct sdma_txreq *txreq = &tx->txreq;
	struct sk_buff *skb = tx->skb;
	int ret = 0;
	int i;

	if (skb_headlen(skb)) {
		ret = sdma_txadd_kvaddr(dd, txreq, skb->data, skb_headlen(skb));
		if (unlikely(ret))
			return ret;
	}

	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
		const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

		ret = sdma_txadd_page(dd,
				      txreq,
				      skb_frag_page(frag),
				      frag->bv_offset,
				      skb_frag_size(frag));
		if (unlikely(ret))
			break;
	}

	return ret;
}

static int hfi1_ipoib_build_tx_desc(struct ipoib_txreq *tx,
				    struct ipoib_txparms *txp)
{
	struct hfi1_devdata *dd = txp->dd;
	struct sdma_txreq *txreq = &tx->txreq;
	struct hfi1_sdma_header *sdma_hdr = tx->sdma_hdr;
	u16 pkt_bytes =
		sizeof(sdma_hdr->pbc) + (txp->hdr_dwords << 2) + tx->skb->len;
	int ret;

	ret = sdma_txinit(txreq, 0, pkt_bytes, hfi1_ipoib_sdma_complete);
	if (unlikely(ret))
		return ret;

	/* add pbc + headers */
	ret = sdma_txadd_kvaddr(dd,
				txreq,
				sdma_hdr,
				sizeof(sdma_hdr->pbc) + (txp->hdr_dwords << 2));
	if (unlikely(ret))
		return ret;

	/* add the ulp payload */
	return hfi1_ipoib_build_ulp_payload(tx, txp);
}

static void hfi1_ipoib_build_ib_tx_headers(struct ipoib_txreq *tx,
					   struct ipoib_txparms *txp)
{
	struct hfi1_ipoib_dev_priv *priv = tx->txq->priv;
	struct hfi1_sdma_header *sdma_hdr = tx->sdma_hdr;
	struct sk_buff *skb = tx->skb;
	struct hfi1_pportdata *ppd = ppd_from_ibp(txp->ibp);
	struct rdma_ah_attr *ah_attr = txp->ah_attr;
	struct ib_other_headers *ohdr;
	struct ib_grh *grh;
	u16 dwords;
	u16 slid;
	u16 dlid;
	u16 lrh0;
	u32 bth0;
	u32 sqpn = (u32)(priv->netdev->dev_addr[1] << 16 |
			 priv->netdev->dev_addr[2] << 8 |
			 priv->netdev->dev_addr[3]);
	u16 payload_dwords;
	u8 pad_cnt;

	pad_cnt = -skb->len & 3;

	/* Includes ICRC */
	payload_dwords = ((skb->len + pad_cnt) >> 2) + SIZE_OF_CRC;

	/* header size in dwords LRH+BTH+DETH = (8+12+8)/4. */
	txp->hdr_dwords = 7;

	if (rdma_ah_get_ah_flags(ah_attr) & IB_AH_GRH) {
		grh = &sdma_hdr->hdr.ibh.u.l.grh;
		txp->hdr_dwords +=
			hfi1_make_grh(txp->ibp,
				      grh,
				      rdma_ah_read_grh(ah_attr),
				      txp->hdr_dwords - LRH_9B_DWORDS,
				      payload_dwords);
		lrh0 = HFI1_LRH_GRH;
		ohdr = &sdma_hdr->hdr.ibh.u.l.oth;
	} else {
		lrh0 = HFI1_LRH_BTH;
		ohdr = &sdma_hdr->hdr.ibh.u.oth;
	}

	lrh0 |= (rdma_ah_get_sl(ah_attr) & 0xf) << 4;
	lrh0 |= (txp->flow.sc5 & 0xf) << 12;

	dlid = opa_get_lid(rdma_ah_get_dlid(ah_attr), 9B);
	if (dlid == be16_to_cpu(IB_LID_PERMISSIVE)) {
		slid = be16_to_cpu(IB_LID_PERMISSIVE);
	} else {
		u16 lid = (u16)ppd->lid;

		if (lid) {
			lid |= rdma_ah_get_path_bits(ah_attr) &
				((1 << ppd->lmc) - 1);
			slid = lid;
		} else {
			slid = be16_to_cpu(IB_LID_PERMISSIVE);
		}
	}

	/* Includes ICRC */
	dwords = txp->hdr_dwords + payload_dwords;

	/* Build the lrh */
	sdma_hdr->hdr.hdr_type = HFI1_PKT_TYPE_9B;
	hfi1_make_ib_hdr(&sdma_hdr->hdr.ibh, lrh0, dwords, dlid, slid);

	/* Build the bth */
	bth0 = (IB_OPCODE_UD_SEND_ONLY << 24) | (pad_cnt << 20) | priv->pkey;

	ohdr->bth[0] = cpu_to_be32(bth0);
	ohdr->bth[1] = cpu_to_be32(txp->dqpn);
	ohdr->bth[2] = cpu_to_be32(mask_psn((u32)txp->txq->tx_ring.sent_txreqs));

	/* Build the deth */
	ohdr->u.ud.deth[0] = cpu_to_be32(priv->qkey);
	ohdr->u.ud.deth[1] = cpu_to_be32((txp->entropy <<
					  HFI1_IPOIB_ENTROPY_SHIFT) | sqpn);

	/* Construct the pbc. */
	sdma_hdr->pbc =
		cpu_to_le64(create_pbc(ppd,
				       ib_is_sc5(txp->flow.sc5) <<
							      PBC_DC_INFO_SHIFT,
				       0,
				       sc_to_vlt(priv->dd, txp->flow.sc5),
				       dwords - SIZE_OF_CRC +
						(sizeof(sdma_hdr->pbc) >> 2)));
}

static struct ipoib_txreq *hfi1_ipoib_send_dma_common(struct net_device *dev,
						      struct sk_buff *skb,
						      struct ipoib_txparms *txp)
{
	struct hfi1_ipoib_dev_priv *priv = hfi1_ipoib_priv(dev);
	struct hfi1_ipoib_txq *txq = txp->txq;
	struct ipoib_txreq *tx;
	struct hfi1_ipoib_circ_buf *tx_ring = &txq->tx_ring;
	u32 tail = tx_ring->tail;
	int ret;

	if (unlikely(!tx_ring->avail)) {
		u32 head;

		if (hfi1_ipoib_used(txq) >= hfi1_ipoib_ring_hwat(txq))
			/* This shouldn't happen with a stopped queue */
			return ERR_PTR(-ENOMEM);
		/* See hfi1_ipoib_poll_tx_ring() */
		head = smp_load_acquire(&tx_ring->head);
		tx_ring->avail =
			min_t(u32, hfi1_ipoib_ring_hwat(txq),
			      CIRC_CNT(head, tail, tx_ring->max_items));
	} else {
		tx_ring->avail--;
	}
	tx = hfi1_txreq_from_idx(tx_ring, tail);
	trace_hfi1_txq_alloc_tx(txq);

	/* so that we can test if the sdma descriptors are there */
	tx->txreq.num_desc = 0;
	tx->txq = txq;
	tx->skb = skb;
	INIT_LIST_HEAD(&tx->txreq.list);

	hfi1_ipoib_build_ib_tx_headers(tx, txp);

	ret = hfi1_ipoib_build_tx_desc(tx, txp);
	if (likely(!ret)) {
		if (txq->flow.as_int != txp->flow.as_int) {
			txq->flow.tx_queue = txp->flow.tx_queue;
			txq->flow.sc5 = txp->flow.sc5;
			txq->sde =
				sdma_select_engine_sc(priv->dd,
						      txp->flow.tx_queue,
						      txp->flow.sc5);
			trace_hfi1_flow_switch(txq);
		}

		return tx;
	}

	sdma_txclean(priv->dd, &tx->txreq);

	return ERR_PTR(ret);
}

static int hfi1_ipoib_submit_tx_list(struct net_device *dev,
				     struct hfi1_ipoib_txq *txq)
{
	int ret;
	u16 count_out;

	ret = sdma_send_txlist(txq->sde,
			       iowait_get_ib_work(&txq->wait),
			       &txq->tx_list,
			       &count_out);
	if (likely(!ret) || ret == -EBUSY || ret == -ECOMM)
		return ret;

	dd_dev_warn(txq->priv->dd, "cannot send skb tx list, err %d.\n", ret);

	return ret;
}

static int hfi1_ipoib_flush_tx_list(struct net_device *dev,
				    struct hfi1_ipoib_txq *txq)
{
	int ret = 0;

	if (!list_empty(&txq->tx_list)) {
		/* Flush the current list */
		ret = hfi1_ipoib_submit_tx_list(dev, txq);

		if (unlikely(ret))
			if (ret != -EBUSY)
				++dev->stats.tx_carrier_errors;
	}

	return ret;
}

static int hfi1_ipoib_submit_tx(struct hfi1_ipoib_txq *txq,
				struct ipoib_txreq *tx)
{
	int ret;

	ret = sdma_send_txreq(txq->sde,
			      iowait_get_ib_work(&txq->wait),
			      &tx->txreq,
			      txq->pkts_sent);
	if (likely(!ret)) {
		txq->pkts_sent = true;
		iowait_starve_clear(txq->pkts_sent, &txq->wait);
	}

	return ret;
}

static int hfi1_ipoib_send_dma_single(struct net_device *dev,
				      struct sk_buff *skb,
				      struct ipoib_txparms *txp)
{
	struct hfi1_ipoib_txq *txq = txp->txq;
	struct hfi1_ipoib_circ_buf *tx_ring;
	struct ipoib_txreq *tx;
	int ret;

	tx = hfi1_ipoib_send_dma_common(dev, skb, txp);
	if (IS_ERR(tx)) {
		int ret = PTR_ERR(tx);

		dev_kfree_skb_any(skb);

		if (ret == -ENOMEM)
			++dev->stats.tx_errors;
		else
			++dev->stats.tx_carrier_errors;

		return NETDEV_TX_OK;
	}

	tx_ring = &txq->tx_ring;
	trace_hfi1_tx_consume(tx, tx_ring->tail);
	/* consume tx */
	smp_store_release(&tx_ring->tail, CIRC_NEXT(tx_ring->tail, tx_ring->max_items));
	ret = hfi1_ipoib_submit_tx(txq, tx);
	if (likely(!ret)) {
tx_ok:
		trace_sdma_output_ibhdr(txq->priv->dd,
					&tx->sdma_hdr->hdr,
					ib_is_sc5(txp->flow.sc5));
		hfi1_ipoib_check_queue_depth(txq);
		return NETDEV_TX_OK;
	}

	txq->pkts_sent = false;

	if (ret == -EBUSY || ret == -ECOMM)
		goto tx_ok;

	/* mark complete and kick napi tx */
	smp_store_release(&tx->complete, 1);
	napi_schedule(&tx->txq->napi);

	++dev->stats.tx_carrier_errors;

	return NETDEV_TX_OK;
}

static int hfi1_ipoib_send_dma_list(struct net_device *dev,
				    struct sk_buff *skb,
				    struct ipoib_txparms *txp)
{
	struct hfi1_ipoib_txq *txq = txp->txq;
	struct hfi1_ipoib_circ_buf *tx_ring;
	struct ipoib_txreq *tx;

	/* Has the flow change ? */
	if (txq->flow.as_int != txp->flow.as_int) {
		int ret;

		trace_hfi1_flow_flush(txq);
		ret = hfi1_ipoib_flush_tx_list(dev, txq);
		if (unlikely(ret)) {
			if (ret == -EBUSY)
				++dev->stats.tx_dropped;
			dev_kfree_skb_any(skb);
			return NETDEV_TX_OK;
		}
	}
	tx = hfi1_ipoib_send_dma_common(dev, skb, txp);
	if (IS_ERR(tx)) {
		int ret = PTR_ERR(tx);

		dev_kfree_skb_any(skb);

		if (ret == -ENOMEM)
			++dev->stats.tx_errors;
		else
			++dev->stats.tx_carrier_errors;

		return NETDEV_TX_OK;
	}

	tx_ring = &txq->tx_ring;
	trace_hfi1_tx_consume(tx, tx_ring->tail);
	/* consume tx */
	smp_store_release(&tx_ring->tail, CIRC_NEXT(tx_ring->tail, tx_ring->max_items));
	list_add_tail(&tx->txreq.list, &txq->tx_list);

	hfi1_ipoib_check_queue_depth(txq);

	trace_sdma_output_ibhdr(txq->priv->dd,
				&tx->sdma_hdr->hdr,
				ib_is_sc5(txp->flow.sc5));

	if (!netdev_xmit_more())
		(void)hfi1_ipoib_flush_tx_list(dev, txq);

	return NETDEV_TX_OK;
}

static u8 hfi1_ipoib_calc_entropy(struct sk_buff *skb)
{
	if (skb_transport_header_was_set(skb)) {
		u8 *hdr = (u8 *)skb_transport_header(skb);

		return (hdr[0] ^ hdr[1] ^ hdr[2] ^ hdr[3]);
	}

	return (u8)skb_get_queue_mapping(skb);
}

int hfi1_ipoib_send(struct net_device *dev,
		    struct sk_buff *skb,
		    struct ib_ah *address,
		    u32 dqpn)
{
	struct hfi1_ipoib_dev_priv *priv = hfi1_ipoib_priv(dev);
	struct ipoib_txparms txp;
	struct rdma_netdev *rn = netdev_priv(dev);

	if (unlikely(skb->len > rn->mtu + HFI1_IPOIB_ENCAP_LEN)) {
		dd_dev_warn(priv->dd, "packet len %d (> %d) too long to send, dropping\n",
			    skb->len,
			    rn->mtu + HFI1_IPOIB_ENCAP_LEN);
		++dev->stats.tx_dropped;
		++dev->stats.tx_errors;
		dev_kfree_skb_any(skb);
		return NETDEV_TX_OK;
	}

	txp.dd = priv->dd;
	txp.ah_attr = &ibah_to_rvtah(address)->attr;
	txp.ibp = to_iport(priv->device, priv->port_num);
	txp.txq = &priv->txqs[skb_get_queue_mapping(skb)];
	txp.dqpn = dqpn;
	txp.flow.sc5 = txp.ibp->sl_to_sc[rdma_ah_get_sl(txp.ah_attr)];
	txp.flow.tx_queue = (u8)skb_get_queue_mapping(skb);
	txp.entropy = hfi1_ipoib_calc_entropy(skb);

	if (netdev_xmit_more() || !list_empty(&txp.txq->tx_list))
		return hfi1_ipoib_send_dma_list(dev, skb, &txp);

	return hfi1_ipoib_send_dma_single(dev, skb,  &txp);
}

/*
 * hfi1_ipoib_sdma_sleep - ipoib sdma sleep function
 *
 * This function gets called from sdma_send_txreq() when there are not enough
 * sdma descriptors available to send the packet. It adds Tx queue's wait
 * structure to sdma engine's dmawait list to be woken up when descriptors
 * become available.
 */
static int hfi1_ipoib_sdma_sleep(struct sdma_engine *sde,
				 struct iowait_work *wait,
				 struct sdma_txreq *txreq,
				 uint seq,
				 bool pkts_sent)
{
	struct hfi1_ipoib_txq *txq =
		container_of(wait->iow, struct hfi1_ipoib_txq, wait);

	write_seqlock(&sde->waitlock);

	if (likely(txq->priv->netdev->reg_state == NETREG_REGISTERED)) {
		if (sdma_progress(sde, seq, txreq)) {
			write_sequnlock(&sde->waitlock);
			return -EAGAIN;
		}

		if (list_empty(&txreq->list))
			/* came from non-list submit */
			list_add_tail(&txreq->list, &txq->tx_list);
		if (list_empty(&txq->wait.list)) {
			struct hfi1_ibport *ibp = &sde->ppd->ibport_data;

			if (!atomic_xchg(&txq->tx_ring.no_desc, 1)) {
				trace_hfi1_txq_queued(txq);
				hfi1_ipoib_stop_txq(txq);
			}
			ibp->rvp.n_dmawait++;
			iowait_queue(pkts_sent, wait->iow, &sde->dmawait);
		}

		write_sequnlock(&sde->waitlock);
		return -EBUSY;
	}

	write_sequnlock(&sde->waitlock);
	return -EINVAL;
}

/*
 * hfi1_ipoib_sdma_wakeup - ipoib sdma wakeup function
 *
 * This function gets called when SDMA descriptors becomes available and Tx
 * queue's wait structure was previously added to sdma engine's dmawait list.
 */
static void hfi1_ipoib_sdma_wakeup(struct iowait *wait, int reason)
{
	struct hfi1_ipoib_txq *txq =
		container_of(wait, struct hfi1_ipoib_txq, wait);

	trace_hfi1_txq_wakeup(txq);
	if (likely(txq->priv->netdev->reg_state == NETREG_REGISTERED))
		iowait_schedule(wait, system_highpri_wq, WORK_CPU_UNBOUND);
}

static void hfi1_ipoib_flush_txq(struct work_struct *work)
{
	struct iowait_work *ioww =
		container_of(work, struct iowait_work, iowork);
	struct iowait *wait = iowait_ioww_to_iow(ioww);
	struct hfi1_ipoib_txq *txq =
		container_of(wait, struct hfi1_ipoib_txq, wait);
	struct net_device *dev = txq->priv->netdev;

	if (likely(dev->reg_state == NETREG_REGISTERED) &&
	    likely(!hfi1_ipoib_flush_tx_list(dev, txq)))
		if (atomic_xchg(&txq->tx_ring.no_desc, 0))
			hfi1_ipoib_wake_txq(txq);
}

int hfi1_ipoib_txreq_init(struct hfi1_ipoib_dev_priv *priv)
{
	struct net_device *dev = priv->netdev;
	u32 tx_ring_size, tx_item_size;
	struct hfi1_ipoib_circ_buf *tx_ring;
	int i, j;

	/*
	 * Ring holds 1 less than tx_ring_size
	 * Round up to next power of 2 in order to hold at least tx_queue_len
	 */
	tx_ring_size = roundup_pow_of_two(dev->tx_queue_len + 1);
	tx_item_size = roundup_pow_of_two(sizeof(struct ipoib_txreq));

	priv->txqs = kcalloc_node(dev->num_tx_queues,
				  sizeof(struct hfi1_ipoib_txq),
				  GFP_KERNEL,
				  priv->dd->node);
	if (!priv->txqs)
		return -ENOMEM;

	for (i = 0; i < dev->num_tx_queues; i++) {
		struct hfi1_ipoib_txq *txq = &priv->txqs[i];
		struct ipoib_txreq *tx;

		tx_ring = &txq->tx_ring;
		iowait_init(&txq->wait,
			    0,
			    hfi1_ipoib_flush_txq,
			    NULL,
			    hfi1_ipoib_sdma_sleep,
			    hfi1_ipoib_sdma_wakeup,
			    NULL,
			    NULL);
		txq->priv = priv;
		txq->sde = NULL;
		INIT_LIST_HEAD(&txq->tx_list);
		atomic_set(&txq->tx_ring.stops, 0);
		atomic_set(&txq->tx_ring.ring_full, 0);
		atomic_set(&txq->tx_ring.no_desc, 0);
		txq->q_idx = i;
		txq->flow.tx_queue = 0xff;
		txq->flow.sc5 = 0xff;
		txq->pkts_sent = false;

		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
					     priv->dd->node);

		txq->tx_ring.items =
			kvzalloc_node(array_size(tx_ring_size, tx_item_size),
				      GFP_KERNEL, priv->dd->node);
		if (!txq->tx_ring.items)
			goto free_txqs;

		txq->tx_ring.max_items = tx_ring_size;
		txq->tx_ring.shift = ilog2(tx_item_size);
		txq->tx_ring.avail = hfi1_ipoib_ring_hwat(txq);
		tx_ring = &txq->tx_ring;
		for (j = 0; j < tx_ring_size; j++)
			hfi1_txreq_from_idx(tx_ring, j)->sdma_hdr =
				kzalloc_node(sizeof(*tx->sdma_hdr),
					     GFP_KERNEL, priv->dd->node);

		netif_tx_napi_add(dev, &txq->napi,
				  hfi1_ipoib_poll_tx_ring,
				  NAPI_POLL_WEIGHT);
	}

	return 0;

free_txqs:
	for (i--; i >= 0; i--) {
		struct hfi1_ipoib_txq *txq = &priv->txqs[i];

		netif_napi_del(&txq->napi);
		tx_ring = &txq->tx_ring;
		for (j = 0; j < tx_ring_size; j++)
			kfree(hfi1_txreq_from_idx(tx_ring, j)->sdma_hdr);
		kvfree(tx_ring->items);
	}

	kfree(priv->txqs);
	priv->txqs = NULL;
	return -ENOMEM;
}

static void hfi1_ipoib_drain_tx_list(struct hfi1_ipoib_txq *txq)
{
	struct sdma_txreq *txreq;
	struct sdma_txreq *txreq_tmp;

	list_for_each_entry_safe(txreq, txreq_tmp, &txq->tx_list, list) {
		struct ipoib_txreq *tx =
			container_of(txreq, struct ipoib_txreq, txreq);

		list_del(&txreq->list);
		sdma_txclean(txq->priv->dd, &tx->txreq);
		dev_kfree_skb_any(tx->skb);
		tx->skb = NULL;
		txq->tx_ring.complete_txreqs++;
	}

	if (hfi1_ipoib_used(txq))
		dd_dev_warn(txq->priv->dd,
			    "txq %d not empty found %u requests\n",
			    txq->q_idx,
			    hfi1_ipoib_txreqs(txq->tx_ring.sent_txreqs,
					      txq->tx_ring.complete_txreqs));
}

void hfi1_ipoib_txreq_deinit(struct hfi1_ipoib_dev_priv *priv)
{
	int i, j;

	for (i = 0; i < priv->netdev->num_tx_queues; i++) {
		struct hfi1_ipoib_txq *txq = &priv->txqs[i];
		struct hfi1_ipoib_circ_buf *tx_ring = &txq->tx_ring;

		iowait_cancel_work(&txq->wait);
		iowait_sdma_drain(&txq->wait);
		hfi1_ipoib_drain_tx_list(txq);
		netif_napi_del(&txq->napi);
		hfi1_ipoib_drain_tx_ring(txq);
		for (j = 0; j < tx_ring->max_items; j++)
			kfree(hfi1_txreq_from_idx(tx_ring, j)->sdma_hdr);
		kvfree(tx_ring->items);
	}

	kfree(priv->txqs);
	priv->txqs = NULL;
}

void hfi1_ipoib_napi_tx_enable(struct net_device *dev)
{
	struct hfi1_ipoib_dev_priv *priv = hfi1_ipoib_priv(dev);
	int i;

	for (i = 0; i < dev->num_tx_queues; i++) {
		struct hfi1_ipoib_txq *txq = &priv->txqs[i];

		napi_enable(&txq->napi);
	}
}

void hfi1_ipoib_napi_tx_disable(struct net_device *dev)
{
	struct hfi1_ipoib_dev_priv *priv = hfi1_ipoib_priv(dev);
	int i;

	for (i = 0; i < dev->num_tx_queues; i++) {
		struct hfi1_ipoib_txq *txq = &priv->txqs[i];

		napi_disable(&txq->napi);
		hfi1_ipoib_drain_tx_ring(txq);
	}
}

void hfi1_ipoib_tx_timeout(struct net_device *dev, unsigned int q)
{
	struct hfi1_ipoib_dev_priv *priv = hfi1_ipoib_priv(dev);
	struct hfi1_ipoib_txq *txq = &priv->txqs[q];

	dd_dev_info(priv->dd, "timeout txq %p q %u stopped %u stops %d no_desc %d ring_full %d\n",
		    txq, q,
		    __netif_subqueue_stopped(dev, txq->q_idx),
		    atomic_read(&txq->tx_ring.stops),
		    atomic_read(&txq->tx_ring.no_desc),
		    atomic_read(&txq->tx_ring.ring_full));
	dd_dev_info(priv->dd, "sde %p engine %u\n",
		    txq->sde,
		    txq->sde ? txq->sde->this_idx : 0);
	dd_dev_info(priv->dd, "flow %x\n", txq->flow.as_int);
	dd_dev_info(priv->dd, "sent %llu completed %llu used %llu\n",
		    txq->tx_ring.sent_txreqs, txq->tx_ring.complete_txreqs,
		    hfi1_ipoib_used(txq));
	dd_dev_info(priv->dd, "tx_queue_len %u max_items %u\n",
		    dev->tx_queue_len, txq->tx_ring.max_items);
	dd_dev_info(priv->dd, "head %u tail %u\n",
		    txq->tx_ring.head, txq->tx_ring.tail);
	dd_dev_info(priv->dd, "wait queued %u\n",
		    !list_empty(&txq->wait.list));
	dd_dev_info(priv->dd, "tx_list empty %u\n",
		    list_empty(&txq->tx_list));
}