xref: /linux/drivers/net/ethernet/intel/ice/ice_txrx.c (revision 07fdad3a93756b872da7b53647715c48d0f4a2d0)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2018, Intel Corporation. */
3 
4 /* The driver transmit and receive code */
5 
6 #include <linux/mm.h>
7 #include <linux/netdevice.h>
8 #include <linux/prefetch.h>
9 #include <linux/bpf_trace.h>
10 #include <net/dsfield.h>
11 #include <net/mpls.h>
12 #include <net/xdp.h>
13 #include "ice_txrx_lib.h"
14 #include "ice_lib.h"
15 #include "ice.h"
16 #include "ice_trace.h"
17 #include "ice_dcb_lib.h"
18 #include "ice_xsk.h"
19 #include "ice_eswitch.h"
20 
21 #define ICE_RX_HDR_SIZE		256
22 
23 #define ICE_FDIR_CLEAN_DELAY 10
24 
25 /**
26  * ice_prgm_fdir_fltr - Program a Flow Director filter
27  * @vsi: VSI to send dummy packet
28  * @fdir_desc: flow director descriptor
29  * @raw_packet: allocated buffer for flow director
30  */
31 int
32 ice_prgm_fdir_fltr(struct ice_vsi *vsi, struct ice_fltr_desc *fdir_desc,
33 		   u8 *raw_packet)
34 {
35 	struct ice_tx_buf *tx_buf, *first;
36 	struct ice_fltr_desc *f_desc;
37 	struct ice_tx_desc *tx_desc;
38 	struct ice_tx_ring *tx_ring;
39 	struct device *dev;
40 	dma_addr_t dma;
41 	u32 td_cmd;
42 	u16 i;
43 
44 	/* VSI and Tx ring */
45 	if (!vsi)
46 		return -ENOENT;
47 	tx_ring = vsi->tx_rings[0];
48 	if (!tx_ring || !tx_ring->desc)
49 		return -ENOENT;
50 	dev = tx_ring->dev;
51 
52 	/* we are using two descriptors to add/del a filter and we can wait */
53 	for (i = ICE_FDIR_CLEAN_DELAY; ICE_DESC_UNUSED(tx_ring) < 2; i--) {
54 		if (!i)
55 			return -EAGAIN;
56 		msleep_interruptible(1);
57 	}
58 
59 	dma = dma_map_single(dev, raw_packet, ICE_FDIR_MAX_RAW_PKT_SIZE,
60 			     DMA_TO_DEVICE);
61 
62 	if (dma_mapping_error(dev, dma))
63 		return -EINVAL;
64 
65 	/* grab the next descriptor */
66 	i = tx_ring->next_to_use;
67 	first = &tx_ring->tx_buf[i];
68 	f_desc = ICE_TX_FDIRDESC(tx_ring, i);
69 	memcpy(f_desc, fdir_desc, sizeof(*f_desc));
70 
71 	i++;
72 	i = (i < tx_ring->count) ? i : 0;
73 	tx_desc = ICE_TX_DESC(tx_ring, i);
74 	tx_buf = &tx_ring->tx_buf[i];
75 
76 	i++;
77 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
78 
79 	memset(tx_buf, 0, sizeof(*tx_buf));
80 	dma_unmap_len_set(tx_buf, len, ICE_FDIR_MAX_RAW_PKT_SIZE);
81 	dma_unmap_addr_set(tx_buf, dma, dma);
82 
83 	tx_desc->buf_addr = cpu_to_le64(dma);
84 	td_cmd = ICE_TXD_LAST_DESC_CMD | ICE_TX_DESC_CMD_DUMMY |
85 		 ICE_TX_DESC_CMD_RE;
86 
87 	tx_buf->type = ICE_TX_BUF_DUMMY;
88 	tx_buf->raw_buf = raw_packet;
89 
90 	tx_desc->cmd_type_offset_bsz =
91 		ice_build_ctob(td_cmd, 0, ICE_FDIR_MAX_RAW_PKT_SIZE, 0);
92 
93 	/* Force memory write to complete before letting h/w know
94 	 * there are new descriptors to fetch.
95 	 */
96 	wmb();
97 
98 	/* mark the data descriptor to be watched */
99 	first->next_to_watch = tx_desc;
100 
101 	writel(tx_ring->next_to_use, tx_ring->tail);
102 
103 	return 0;
104 }
105 
106 /**
107  * ice_unmap_and_free_tx_buf - Release a Tx buffer
108  * @ring: the ring that owns the buffer
109  * @tx_buf: the buffer to free
110  */
111 static void
112 ice_unmap_and_free_tx_buf(struct ice_tx_ring *ring, struct ice_tx_buf *tx_buf)
113 {
114 	if (dma_unmap_len(tx_buf, len))
115 		dma_unmap_page(ring->dev,
116 			       dma_unmap_addr(tx_buf, dma),
117 			       dma_unmap_len(tx_buf, len),
118 			       DMA_TO_DEVICE);
119 
120 	switch (tx_buf->type) {
121 	case ICE_TX_BUF_DUMMY:
122 		devm_kfree(ring->dev, tx_buf->raw_buf);
123 		break;
124 	case ICE_TX_BUF_SKB:
125 		dev_kfree_skb_any(tx_buf->skb);
126 		break;
127 	case ICE_TX_BUF_XDP_TX:
128 		page_frag_free(tx_buf->raw_buf);
129 		break;
130 	case ICE_TX_BUF_XDP_XMIT:
131 		xdp_return_frame(tx_buf->xdpf);
132 		break;
133 	}
134 
135 	tx_buf->next_to_watch = NULL;
136 	tx_buf->type = ICE_TX_BUF_EMPTY;
137 	dma_unmap_len_set(tx_buf, len, 0);
138 	/* tx_buf must be completely set up in the transmit path */
139 }
140 
141 static struct netdev_queue *txring_txq(const struct ice_tx_ring *ring)
142 {
143 	return netdev_get_tx_queue(ring->netdev, ring->q_index);
144 }
145 
146 /**
147  * ice_clean_tstamp_ring - clean time stamp ring
148  * @tx_ring: Tx ring to clean the Time Stamp ring for
149  */
150 static void ice_clean_tstamp_ring(struct ice_tx_ring *tx_ring)
151 {
152 	struct ice_tstamp_ring *tstamp_ring = tx_ring->tstamp_ring;
153 	u32 size;
154 
155 	if (!tstamp_ring->desc)
156 		return;
157 
158 	size = ALIGN(tstamp_ring->count * sizeof(struct ice_ts_desc),
159 		     PAGE_SIZE);
160 	memset(tstamp_ring->desc, 0, size);
161 	tstamp_ring->next_to_use = 0;
162 }
163 
164 /**
165  * ice_free_tstamp_ring - free time stamp resources per queue
166  * @tx_ring: Tx ring to free the Time Stamp ring for
167  */
168 void ice_free_tstamp_ring(struct ice_tx_ring *tx_ring)
169 {
170 	struct ice_tstamp_ring *tstamp_ring = tx_ring->tstamp_ring;
171 	u32 size;
172 
173 	if (!tstamp_ring->desc)
174 		return;
175 
176 	ice_clean_tstamp_ring(tx_ring);
177 	size = ALIGN(tstamp_ring->count * sizeof(struct ice_ts_desc),
178 		     PAGE_SIZE);
179 	dmam_free_coherent(tx_ring->dev, size, tstamp_ring->desc,
180 			   tstamp_ring->dma);
181 	tstamp_ring->desc = NULL;
182 }
183 
184 /**
185  * ice_free_tx_tstamp_ring - free time stamp resources per Tx ring
186  * @tx_ring: Tx ring to free the Time Stamp ring for
187  */
188 void ice_free_tx_tstamp_ring(struct ice_tx_ring *tx_ring)
189 {
190 	ice_free_tstamp_ring(tx_ring);
191 	kfree_rcu(tx_ring->tstamp_ring, rcu);
192 	tx_ring->tstamp_ring = NULL;
193 	tx_ring->flags &= ~ICE_TX_FLAGS_TXTIME;
194 }
195 
196 /**
197  * ice_clean_tx_ring - Free any empty Tx buffers
198  * @tx_ring: ring to be cleaned
199  */
200 void ice_clean_tx_ring(struct ice_tx_ring *tx_ring)
201 {
202 	u32 size;
203 	u16 i;
204 
205 	if (ice_ring_is_xdp(tx_ring) && tx_ring->xsk_pool) {
206 		ice_xsk_clean_xdp_ring(tx_ring);
207 		goto tx_skip_free;
208 	}
209 
210 	/* ring already cleared, nothing to do */
211 	if (!tx_ring->tx_buf)
212 		return;
213 
214 	/* Free all the Tx ring sk_buffs */
215 	for (i = 0; i < tx_ring->count; i++)
216 		ice_unmap_and_free_tx_buf(tx_ring, &tx_ring->tx_buf[i]);
217 
218 tx_skip_free:
219 	memset(tx_ring->tx_buf, 0, sizeof(*tx_ring->tx_buf) * tx_ring->count);
220 
221 	size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
222 		     PAGE_SIZE);
223 	/* Zero out the descriptor ring */
224 	memset(tx_ring->desc, 0, size);
225 
226 	tx_ring->next_to_use = 0;
227 	tx_ring->next_to_clean = 0;
228 
229 	if (!tx_ring->netdev)
230 		return;
231 
232 	/* cleanup Tx queue statistics */
233 	netdev_tx_reset_queue(txring_txq(tx_ring));
234 
235 	if (ice_is_txtime_cfg(tx_ring))
236 		ice_free_tx_tstamp_ring(tx_ring);
237 }
238 
239 /**
240  * ice_free_tx_ring - Free Tx resources per queue
241  * @tx_ring: Tx descriptor ring for a specific queue
242  *
243  * Free all transmit software resources
244  */
245 void ice_free_tx_ring(struct ice_tx_ring *tx_ring)
246 {
247 	u32 size;
248 
249 	ice_clean_tx_ring(tx_ring);
250 	devm_kfree(tx_ring->dev, tx_ring->tx_buf);
251 	tx_ring->tx_buf = NULL;
252 
253 	if (tx_ring->desc) {
254 		size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
255 			     PAGE_SIZE);
256 		dmam_free_coherent(tx_ring->dev, size,
257 				   tx_ring->desc, tx_ring->dma);
258 		tx_ring->desc = NULL;
259 	}
260 }
261 
262 /**
263  * ice_clean_tx_irq - Reclaim resources after transmit completes
264  * @tx_ring: Tx ring to clean
265  * @napi_budget: Used to determine if we are in netpoll
266  *
267  * Returns true if there's any budget left (e.g. the clean is finished)
268  */
269 static bool ice_clean_tx_irq(struct ice_tx_ring *tx_ring, int napi_budget)
270 {
271 	unsigned int total_bytes = 0, total_pkts = 0;
272 	unsigned int budget = ICE_DFLT_IRQ_WORK;
273 	struct ice_vsi *vsi = tx_ring->vsi;
274 	s16 i = tx_ring->next_to_clean;
275 	struct ice_tx_desc *tx_desc;
276 	struct ice_tx_buf *tx_buf;
277 
278 	/* get the bql data ready */
279 	netdev_txq_bql_complete_prefetchw(txring_txq(tx_ring));
280 
281 	tx_buf = &tx_ring->tx_buf[i];
282 	tx_desc = ICE_TX_DESC(tx_ring, i);
283 	i -= tx_ring->count;
284 
285 	prefetch(&vsi->state);
286 
287 	do {
288 		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
289 
290 		/* if next_to_watch is not set then there is no work pending */
291 		if (!eop_desc)
292 			break;
293 
294 		/* follow the guidelines of other drivers */
295 		prefetchw(&tx_buf->skb->users);
296 
297 		smp_rmb();	/* prevent any other reads prior to eop_desc */
298 
299 		ice_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
300 		/* if the descriptor isn't done, no work yet to do */
301 		if (!(eop_desc->cmd_type_offset_bsz &
302 		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
303 			break;
304 
305 		/* clear next_to_watch to prevent false hangs */
306 		tx_buf->next_to_watch = NULL;
307 
308 		/* update the statistics for this packet */
309 		total_bytes += tx_buf->bytecount;
310 		total_pkts += tx_buf->gso_segs;
311 
312 		/* free the skb */
313 		napi_consume_skb(tx_buf->skb, napi_budget);
314 
315 		/* unmap skb header data */
316 		dma_unmap_single(tx_ring->dev,
317 				 dma_unmap_addr(tx_buf, dma),
318 				 dma_unmap_len(tx_buf, len),
319 				 DMA_TO_DEVICE);
320 
321 		/* clear tx_buf data */
322 		tx_buf->type = ICE_TX_BUF_EMPTY;
323 		dma_unmap_len_set(tx_buf, len, 0);
324 
325 		/* unmap remaining buffers */
326 		while (tx_desc != eop_desc) {
327 			ice_trace(clean_tx_irq_unmap, tx_ring, tx_desc, tx_buf);
328 			tx_buf++;
329 			tx_desc++;
330 			i++;
331 			if (unlikely(!i)) {
332 				i -= tx_ring->count;
333 				tx_buf = tx_ring->tx_buf;
334 				tx_desc = ICE_TX_DESC(tx_ring, 0);
335 			}
336 
337 			/* unmap any remaining paged data */
338 			if (dma_unmap_len(tx_buf, len)) {
339 				dma_unmap_page(tx_ring->dev,
340 					       dma_unmap_addr(tx_buf, dma),
341 					       dma_unmap_len(tx_buf, len),
342 					       DMA_TO_DEVICE);
343 				dma_unmap_len_set(tx_buf, len, 0);
344 			}
345 		}
346 		ice_trace(clean_tx_irq_unmap_eop, tx_ring, tx_desc, tx_buf);
347 
348 		/* move us one more past the eop_desc for start of next pkt */
349 		tx_buf++;
350 		tx_desc++;
351 		i++;
352 		if (unlikely(!i)) {
353 			i -= tx_ring->count;
354 			tx_buf = tx_ring->tx_buf;
355 			tx_desc = ICE_TX_DESC(tx_ring, 0);
356 		}
357 
358 		prefetch(tx_desc);
359 
360 		/* update budget accounting */
361 		budget--;
362 	} while (likely(budget));
363 
364 	i += tx_ring->count;
365 	tx_ring->next_to_clean = i;
366 
367 	ice_update_tx_ring_stats(tx_ring, total_pkts, total_bytes);
368 	netdev_tx_completed_queue(txring_txq(tx_ring), total_pkts, total_bytes);
369 
370 #define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
371 	if (unlikely(total_pkts && netif_carrier_ok(tx_ring->netdev) &&
372 		     (ICE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
373 		/* Make sure that anybody stopping the queue after this
374 		 * sees the new next_to_clean.
375 		 */
376 		smp_mb();
377 		if (netif_tx_queue_stopped(txring_txq(tx_ring)) &&
378 		    !test_bit(ICE_VSI_DOWN, vsi->state)) {
379 			netif_tx_wake_queue(txring_txq(tx_ring));
380 			++tx_ring->ring_stats->tx_stats.restart_q;
381 		}
382 	}
383 
384 	return !!budget;
385 }
386 
387 /**
388  * ice_alloc_tstamp_ring - allocate the Time Stamp ring
389  * @tx_ring: Tx ring to allocate the Time Stamp ring for
390  *
391  * Return: 0 on success, negative on error
392  */
393 static int ice_alloc_tstamp_ring(struct ice_tx_ring *tx_ring)
394 {
395 	struct ice_tstamp_ring *tstamp_ring;
396 
397 	/* allocate with kzalloc(), free with kfree_rcu() */
398 	tstamp_ring = kzalloc(sizeof(*tstamp_ring), GFP_KERNEL);
399 	if (!tstamp_ring)
400 		return -ENOMEM;
401 
402 	tstamp_ring->tx_ring = tx_ring;
403 	tx_ring->tstamp_ring = tstamp_ring;
404 	tstamp_ring->desc = NULL;
405 	tstamp_ring->count = ice_calc_ts_ring_count(tx_ring);
406 	tx_ring->flags |= ICE_TX_FLAGS_TXTIME;
407 	return 0;
408 }
409 
410 /**
411  * ice_setup_tstamp_ring - allocate the Time Stamp ring
412  * @tx_ring: Tx ring to set up the Time Stamp ring for
413  *
414  * Return: 0 on success, negative on error
415  */
416 static int ice_setup_tstamp_ring(struct ice_tx_ring *tx_ring)
417 {
418 	struct ice_tstamp_ring *tstamp_ring = tx_ring->tstamp_ring;
419 	struct device *dev = tx_ring->dev;
420 	u32 size;
421 
422 	/* round up to nearest page */
423 	size = ALIGN(tstamp_ring->count * sizeof(struct ice_ts_desc),
424 		     PAGE_SIZE);
425 	tstamp_ring->desc = dmam_alloc_coherent(dev, size, &tstamp_ring->dma,
426 						GFP_KERNEL);
427 	if (!tstamp_ring->desc) {
428 		dev_err(dev, "Unable to allocate memory for Time stamp Ring, size=%d\n",
429 			size);
430 		return -ENOMEM;
431 	}
432 
433 	tstamp_ring->next_to_use = 0;
434 	return 0;
435 }
436 
437 /**
438  * ice_alloc_setup_tstamp_ring - Allocate and setup the Time Stamp ring
439  * @tx_ring: Tx ring to allocate and setup the Time Stamp ring for
440  *
441  * Return: 0 on success, negative on error
442  */
443 int ice_alloc_setup_tstamp_ring(struct ice_tx_ring *tx_ring)
444 {
445 	struct device *dev = tx_ring->dev;
446 	int err;
447 
448 	err = ice_alloc_tstamp_ring(tx_ring);
449 	if (err) {
450 		dev_err(dev, "Unable to allocate Time stamp ring for Tx ring %d\n",
451 			tx_ring->q_index);
452 		return err;
453 	}
454 
455 	err = ice_setup_tstamp_ring(tx_ring);
456 	if (err) {
457 		dev_err(dev, "Unable to setup Time stamp ring for Tx ring %d\n",
458 			tx_ring->q_index);
459 		ice_free_tx_tstamp_ring(tx_ring);
460 		return err;
461 	}
462 	return 0;
463 }
464 
465 /**
466  * ice_setup_tx_ring - Allocate the Tx descriptors
467  * @tx_ring: the Tx ring to set up
468  *
469  * Return 0 on success, negative on error
470  */
471 int ice_setup_tx_ring(struct ice_tx_ring *tx_ring)
472 {
473 	struct device *dev = tx_ring->dev;
474 	u32 size;
475 
476 	if (!dev)
477 		return -ENOMEM;
478 
479 	/* warn if we are about to overwrite the pointer */
480 	WARN_ON(tx_ring->tx_buf);
481 	tx_ring->tx_buf =
482 		devm_kcalloc(dev, sizeof(*tx_ring->tx_buf), tx_ring->count,
483 			     GFP_KERNEL);
484 	if (!tx_ring->tx_buf)
485 		return -ENOMEM;
486 
487 	/* round up to nearest page */
488 	size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
489 		     PAGE_SIZE);
490 	tx_ring->desc = dmam_alloc_coherent(dev, size, &tx_ring->dma,
491 					    GFP_KERNEL);
492 	if (!tx_ring->desc) {
493 		dev_err(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
494 			size);
495 		goto err;
496 	}
497 
498 	tx_ring->next_to_use = 0;
499 	tx_ring->next_to_clean = 0;
500 	tx_ring->ring_stats->tx_stats.prev_pkt = -1;
501 	return 0;
502 
503 err:
504 	devm_kfree(dev, tx_ring->tx_buf);
505 	tx_ring->tx_buf = NULL;
506 	return -ENOMEM;
507 }
508 
509 /**
510  * ice_clean_rx_ring - Free Rx buffers
511  * @rx_ring: ring to be cleaned
512  */
513 void ice_clean_rx_ring(struct ice_rx_ring *rx_ring)
514 {
515 	struct xdp_buff *xdp = &rx_ring->xdp;
516 	struct device *dev = rx_ring->dev;
517 	u32 size;
518 	u16 i;
519 
520 	/* ring already cleared, nothing to do */
521 	if (!rx_ring->rx_buf)
522 		return;
523 
524 	if (rx_ring->xsk_pool) {
525 		ice_xsk_clean_rx_ring(rx_ring);
526 		goto rx_skip_free;
527 	}
528 
529 	if (xdp->data) {
530 		xdp_return_buff(xdp);
531 		xdp->data = NULL;
532 	}
533 
534 	/* Free all the Rx ring sk_buffs */
535 	for (i = 0; i < rx_ring->count; i++) {
536 		struct ice_rx_buf *rx_buf = &rx_ring->rx_buf[i];
537 
538 		if (!rx_buf->page)
539 			continue;
540 
541 		/* Invalidate cache lines that may have been written to by
542 		 * device so that we avoid corrupting memory.
543 		 */
544 		dma_sync_single_range_for_cpu(dev, rx_buf->dma,
545 					      rx_buf->page_offset,
546 					      rx_ring->rx_buf_len,
547 					      DMA_FROM_DEVICE);
548 
549 		/* free resources associated with mapping */
550 		dma_unmap_page_attrs(dev, rx_buf->dma, ice_rx_pg_size(rx_ring),
551 				     DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
552 		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
553 
554 		rx_buf->page = NULL;
555 		rx_buf->page_offset = 0;
556 	}
557 
558 rx_skip_free:
559 	if (rx_ring->xsk_pool)
560 		memset(rx_ring->xdp_buf, 0, array_size(rx_ring->count, sizeof(*rx_ring->xdp_buf)));
561 	else
562 		memset(rx_ring->rx_buf, 0, array_size(rx_ring->count, sizeof(*rx_ring->rx_buf)));
563 
564 	/* Zero out the descriptor ring */
565 	size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
566 		     PAGE_SIZE);
567 	memset(rx_ring->desc, 0, size);
568 
569 	rx_ring->next_to_alloc = 0;
570 	rx_ring->next_to_clean = 0;
571 	rx_ring->first_desc = 0;
572 	rx_ring->next_to_use = 0;
573 }
574 
575 /**
576  * ice_free_rx_ring - Free Rx resources
577  * @rx_ring: ring to clean the resources from
578  *
579  * Free all receive software resources
580  */
581 void ice_free_rx_ring(struct ice_rx_ring *rx_ring)
582 {
583 	u32 size;
584 
585 	ice_clean_rx_ring(rx_ring);
586 	if (rx_ring->vsi->type == ICE_VSI_PF)
587 		if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
588 			xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
589 	WRITE_ONCE(rx_ring->xdp_prog, NULL);
590 	if (rx_ring->xsk_pool) {
591 		kfree(rx_ring->xdp_buf);
592 		rx_ring->xdp_buf = NULL;
593 	} else {
594 		kfree(rx_ring->rx_buf);
595 		rx_ring->rx_buf = NULL;
596 	}
597 
598 	if (rx_ring->desc) {
599 		size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
600 			     PAGE_SIZE);
601 		dmam_free_coherent(rx_ring->dev, size,
602 				   rx_ring->desc, rx_ring->dma);
603 		rx_ring->desc = NULL;
604 	}
605 }
606 
607 /**
608  * ice_setup_rx_ring - Allocate the Rx descriptors
609  * @rx_ring: the Rx ring to set up
610  *
611  * Return 0 on success, negative on error
612  */
613 int ice_setup_rx_ring(struct ice_rx_ring *rx_ring)
614 {
615 	struct device *dev = rx_ring->dev;
616 	u32 size;
617 
618 	if (!dev)
619 		return -ENOMEM;
620 
621 	/* warn if we are about to overwrite the pointer */
622 	WARN_ON(rx_ring->rx_buf);
623 	rx_ring->rx_buf =
624 		kcalloc(rx_ring->count, sizeof(*rx_ring->rx_buf), GFP_KERNEL);
625 	if (!rx_ring->rx_buf)
626 		return -ENOMEM;
627 
628 	/* round up to nearest page */
629 	size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
630 		     PAGE_SIZE);
631 	rx_ring->desc = dmam_alloc_coherent(dev, size, &rx_ring->dma,
632 					    GFP_KERNEL);
633 	if (!rx_ring->desc) {
634 		dev_err(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
635 			size);
636 		goto err;
637 	}
638 
639 	rx_ring->next_to_use = 0;
640 	rx_ring->next_to_clean = 0;
641 	rx_ring->first_desc = 0;
642 
643 	if (ice_is_xdp_ena_vsi(rx_ring->vsi))
644 		WRITE_ONCE(rx_ring->xdp_prog, rx_ring->vsi->xdp_prog);
645 
646 	return 0;
647 
648 err:
649 	kfree(rx_ring->rx_buf);
650 	rx_ring->rx_buf = NULL;
651 	return -ENOMEM;
652 }
653 
654 /**
655  * ice_run_xdp - Executes an XDP program on initialized xdp_buff
656  * @rx_ring: Rx ring
657  * @xdp: xdp_buff used as input to the XDP program
658  * @xdp_prog: XDP program to run
659  * @xdp_ring: ring to be used for XDP_TX action
660  * @eop_desc: Last descriptor in packet to read metadata from
661  *
662  * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR}
663  */
664 static u32
665 ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
666 	    struct bpf_prog *xdp_prog, struct ice_tx_ring *xdp_ring,
667 	    union ice_32b_rx_flex_desc *eop_desc)
668 {
669 	unsigned int ret = ICE_XDP_PASS;
670 	u32 act;
671 
672 	if (!xdp_prog)
673 		goto exit;
674 
675 	ice_xdp_meta_set_desc(xdp, eop_desc);
676 
677 	act = bpf_prog_run_xdp(xdp_prog, xdp);
678 	switch (act) {
679 	case XDP_PASS:
680 		break;
681 	case XDP_TX:
682 		if (static_branch_unlikely(&ice_xdp_locking_key))
683 			spin_lock(&xdp_ring->tx_lock);
684 		ret = __ice_xmit_xdp_ring(xdp, xdp_ring, false);
685 		if (static_branch_unlikely(&ice_xdp_locking_key))
686 			spin_unlock(&xdp_ring->tx_lock);
687 		if (ret == ICE_XDP_CONSUMED)
688 			goto out_failure;
689 		break;
690 	case XDP_REDIRECT:
691 		if (xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog))
692 			goto out_failure;
693 		ret = ICE_XDP_REDIR;
694 		break;
695 	default:
696 		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
697 		fallthrough;
698 	case XDP_ABORTED:
699 out_failure:
700 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
701 		fallthrough;
702 	case XDP_DROP:
703 		ret = ICE_XDP_CONSUMED;
704 	}
705 exit:
706 	return ret;
707 }
708 
709 /**
710  * ice_xmit_xdp_ring - submit frame to XDP ring for transmission
711  * @xdpf: XDP frame that will be converted to XDP buff
712  * @xdp_ring: XDP ring for transmission
713  */
714 static int ice_xmit_xdp_ring(const struct xdp_frame *xdpf,
715 			     struct ice_tx_ring *xdp_ring)
716 {
717 	struct xdp_buff xdp;
718 
719 	xdp.data_hard_start = (void *)xdpf;
720 	xdp.data = xdpf->data;
721 	xdp.data_end = xdp.data + xdpf->len;
722 	xdp.frame_sz = xdpf->frame_sz;
723 	xdp.flags = xdpf->flags;
724 
725 	return __ice_xmit_xdp_ring(&xdp, xdp_ring, true);
726 }
727 
728 /**
729  * ice_xdp_xmit - submit packets to XDP ring for transmission
730  * @dev: netdev
731  * @n: number of XDP frames to be transmitted
732  * @frames: XDP frames to be transmitted
733  * @flags: transmit flags
734  *
735  * Returns number of frames successfully sent. Failed frames
736  * will be free'ed by XDP core.
737  * For error cases, a negative errno code is returned and no-frames
738  * are transmitted (caller must handle freeing frames).
739  */
740 int
741 ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
742 	     u32 flags)
743 {
744 	struct ice_netdev_priv *np = netdev_priv(dev);
745 	unsigned int queue_index = smp_processor_id();
746 	struct ice_vsi *vsi = np->vsi;
747 	struct ice_tx_ring *xdp_ring;
748 	struct ice_tx_buf *tx_buf;
749 	int nxmit = 0, i;
750 
751 	if (test_bit(ICE_VSI_DOWN, vsi->state))
752 		return -ENETDOWN;
753 
754 	if (!ice_is_xdp_ena_vsi(vsi))
755 		return -ENXIO;
756 
757 	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
758 		return -EINVAL;
759 
760 	if (static_branch_unlikely(&ice_xdp_locking_key)) {
761 		queue_index %= vsi->num_xdp_txq;
762 		xdp_ring = vsi->xdp_rings[queue_index];
763 		spin_lock(&xdp_ring->tx_lock);
764 	} else {
765 		/* Generally, should not happen */
766 		if (unlikely(queue_index >= vsi->num_xdp_txq))
767 			return -ENXIO;
768 		xdp_ring = vsi->xdp_rings[queue_index];
769 	}
770 
771 	tx_buf = &xdp_ring->tx_buf[xdp_ring->next_to_use];
772 	for (i = 0; i < n; i++) {
773 		const struct xdp_frame *xdpf = frames[i];
774 		int err;
775 
776 		err = ice_xmit_xdp_ring(xdpf, xdp_ring);
777 		if (err != ICE_XDP_TX)
778 			break;
779 		nxmit++;
780 	}
781 
782 	tx_buf->rs_idx = ice_set_rs_bit(xdp_ring);
783 	if (unlikely(flags & XDP_XMIT_FLUSH))
784 		ice_xdp_ring_update_tail(xdp_ring);
785 
786 	if (static_branch_unlikely(&ice_xdp_locking_key))
787 		spin_unlock(&xdp_ring->tx_lock);
788 
789 	return nxmit;
790 }
791 
792 /**
793  * ice_alloc_mapped_page - recycle or make a new page
794  * @rx_ring: ring to use
795  * @bi: rx_buf struct to modify
796  *
797  * Returns true if the page was successfully allocated or
798  * reused.
799  */
800 static bool
801 ice_alloc_mapped_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *bi)
802 {
803 	struct page *page = bi->page;
804 	dma_addr_t dma;
805 
806 	/* since we are recycling buffers we should seldom need to alloc */
807 	if (likely(page))
808 		return true;
809 
810 	/* alloc new page for storage */
811 	page = dev_alloc_pages(ice_rx_pg_order(rx_ring));
812 	if (unlikely(!page)) {
813 		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
814 		return false;
815 	}
816 
817 	/* map page for use */
818 	dma = dma_map_page_attrs(rx_ring->dev, page, 0, ice_rx_pg_size(rx_ring),
819 				 DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
820 
821 	/* if mapping failed free memory back to system since
822 	 * there isn't much point in holding memory we can't use
823 	 */
824 	if (dma_mapping_error(rx_ring->dev, dma)) {
825 		__free_pages(page, ice_rx_pg_order(rx_ring));
826 		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
827 		return false;
828 	}
829 
830 	bi->dma = dma;
831 	bi->page = page;
832 	bi->page_offset = rx_ring->rx_offset;
833 	page_ref_add(page, USHRT_MAX - 1);
834 	bi->pagecnt_bias = USHRT_MAX;
835 
836 	return true;
837 }
838 
839 /**
840  * ice_init_ctrl_rx_descs - Initialize Rx descriptors for control vsi.
841  * @rx_ring: ring to init descriptors on
842  * @count: number of descriptors to initialize
843  */
844 void ice_init_ctrl_rx_descs(struct ice_rx_ring *rx_ring, u32 count)
845 {
846 	union ice_32b_rx_flex_desc *rx_desc;
847 	u32 ntu = rx_ring->next_to_use;
848 
849 	if (!count)
850 		return;
851 
852 	rx_desc = ICE_RX_DESC(rx_ring, ntu);
853 
854 	do {
855 		rx_desc++;
856 		ntu++;
857 		if (unlikely(ntu == rx_ring->count)) {
858 			rx_desc = ICE_RX_DESC(rx_ring, 0);
859 			ntu = 0;
860 		}
861 
862 		rx_desc->wb.status_error0 = 0;
863 		count--;
864 	} while (count);
865 
866 	if (rx_ring->next_to_use != ntu)
867 		ice_release_rx_desc(rx_ring, ntu);
868 }
869 
870 /**
871  * ice_alloc_rx_bufs - Replace used receive buffers
872  * @rx_ring: ring to place buffers on
873  * @cleaned_count: number of buffers to replace
874  *
875  * Returns false if all allocations were successful, true if any fail. Returning
876  * true signals to the caller that we didn't replace cleaned_count buffers and
877  * there is more work to do.
878  *
879  * First, try to clean "cleaned_count" Rx buffers. Then refill the cleaned Rx
880  * buffers. Then bump tail at most one time. Grouping like this lets us avoid
881  * multiple tail writes per call.
882  */
883 bool ice_alloc_rx_bufs(struct ice_rx_ring *rx_ring, unsigned int cleaned_count)
884 {
885 	union ice_32b_rx_flex_desc *rx_desc;
886 	u16 ntu = rx_ring->next_to_use;
887 	struct ice_rx_buf *bi;
888 
889 	/* do nothing if no valid netdev defined */
890 	if (!rx_ring->netdev || !cleaned_count)
891 		return false;
892 
893 	/* get the Rx descriptor and buffer based on next_to_use */
894 	rx_desc = ICE_RX_DESC(rx_ring, ntu);
895 	bi = &rx_ring->rx_buf[ntu];
896 
897 	do {
898 		/* if we fail here, we have work remaining */
899 		if (!ice_alloc_mapped_page(rx_ring, bi))
900 			break;
901 
902 		/* sync the buffer for use by the device */
903 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
904 						 bi->page_offset,
905 						 rx_ring->rx_buf_len,
906 						 DMA_FROM_DEVICE);
907 
908 		/* Refresh the desc even if buffer_addrs didn't change
909 		 * because each write-back erases this info.
910 		 */
911 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
912 
913 		rx_desc++;
914 		bi++;
915 		ntu++;
916 		if (unlikely(ntu == rx_ring->count)) {
917 			rx_desc = ICE_RX_DESC(rx_ring, 0);
918 			bi = rx_ring->rx_buf;
919 			ntu = 0;
920 		}
921 
922 		/* clear the status bits for the next_to_use descriptor */
923 		rx_desc->wb.status_error0 = 0;
924 
925 		cleaned_count--;
926 	} while (cleaned_count);
927 
928 	if (rx_ring->next_to_use != ntu)
929 		ice_release_rx_desc(rx_ring, ntu);
930 
931 	return !!cleaned_count;
932 }
933 
934 /**
935  * ice_rx_buf_adjust_pg_offset - Prepare Rx buffer for reuse
936  * @rx_buf: Rx buffer to adjust
937  * @size: Size of adjustment
938  *
939  * Update the offset within page so that Rx buf will be ready to be reused.
940  * For systems with PAGE_SIZE < 8192 this function will flip the page offset
941  * so the second half of page assigned to Rx buffer will be used, otherwise
942  * the offset is moved by "size" bytes
943  */
944 static void
945 ice_rx_buf_adjust_pg_offset(struct ice_rx_buf *rx_buf, unsigned int size)
946 {
947 #if (PAGE_SIZE < 8192)
948 	/* flip page offset to other buffer */
949 	rx_buf->page_offset ^= size;
950 #else
951 	/* move offset up to the next cache line */
952 	rx_buf->page_offset += size;
953 #endif
954 }
955 
956 /**
957  * ice_can_reuse_rx_page - Determine if page can be reused for another Rx
958  * @rx_buf: buffer containing the page
959  *
960  * If page is reusable, we have a green light for calling ice_reuse_rx_page,
961  * which will assign the current buffer to the buffer that next_to_alloc is
962  * pointing to; otherwise, the DMA mapping needs to be destroyed and
963  * page freed
964  */
965 static bool
966 ice_can_reuse_rx_page(struct ice_rx_buf *rx_buf)
967 {
968 	unsigned int pagecnt_bias = rx_buf->pagecnt_bias;
969 	struct page *page = rx_buf->page;
970 
971 	/* avoid re-using remote and pfmemalloc pages */
972 	if (!dev_page_is_reusable(page))
973 		return false;
974 
975 	/* if we are only owner of page we can reuse it */
976 	if (unlikely(rx_buf->pgcnt - pagecnt_bias > 1))
977 		return false;
978 #if (PAGE_SIZE >= 8192)
979 #define ICE_LAST_OFFSET \
980 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - ICE_RXBUF_3072)
981 	if (rx_buf->page_offset > ICE_LAST_OFFSET)
982 		return false;
983 #endif /* PAGE_SIZE >= 8192) */
984 
985 	/* If we have drained the page fragment pool we need to update
986 	 * the pagecnt_bias and page count so that we fully restock the
987 	 * number of references the driver holds.
988 	 */
989 	if (unlikely(pagecnt_bias == 1)) {
990 		page_ref_add(page, USHRT_MAX - 1);
991 		rx_buf->pagecnt_bias = USHRT_MAX;
992 	}
993 
994 	return true;
995 }
996 
997 /**
998  * ice_add_xdp_frag - Add contents of Rx buffer to xdp buf as a frag
999  * @rx_ring: Rx descriptor ring to transact packets on
1000  * @xdp: xdp buff to place the data into
1001  * @rx_buf: buffer containing page to add
1002  * @size: packet length from rx_desc
1003  *
1004  * This function will add the data contained in rx_buf->page to the xdp buf.
1005  * It will just attach the page as a frag.
1006  */
1007 static int
1008 ice_add_xdp_frag(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
1009 		 struct ice_rx_buf *rx_buf, const unsigned int size)
1010 {
1011 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
1012 
1013 	if (!size)
1014 		return 0;
1015 
1016 	if (!xdp_buff_has_frags(xdp)) {
1017 		sinfo->nr_frags = 0;
1018 		sinfo->xdp_frags_size = 0;
1019 		xdp_buff_set_frags_flag(xdp);
1020 	}
1021 
1022 	if (unlikely(sinfo->nr_frags == MAX_SKB_FRAGS))
1023 		return -ENOMEM;
1024 
1025 	__skb_fill_page_desc_noacc(sinfo, sinfo->nr_frags++, rx_buf->page,
1026 				   rx_buf->page_offset, size);
1027 	sinfo->xdp_frags_size += size;
1028 
1029 	if (page_is_pfmemalloc(rx_buf->page))
1030 		xdp_buff_set_frag_pfmemalloc(xdp);
1031 
1032 	return 0;
1033 }
1034 
1035 /**
1036  * ice_reuse_rx_page - page flip buffer and store it back on the ring
1037  * @rx_ring: Rx descriptor ring to store buffers on
1038  * @old_buf: donor buffer to have page reused
1039  *
1040  * Synchronizes page for reuse by the adapter
1041  */
1042 static void
1043 ice_reuse_rx_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *old_buf)
1044 {
1045 	u16 nta = rx_ring->next_to_alloc;
1046 	struct ice_rx_buf *new_buf;
1047 
1048 	new_buf = &rx_ring->rx_buf[nta];
1049 
1050 	/* update, and store next to alloc */
1051 	nta++;
1052 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
1053 
1054 	/* Transfer page from old buffer to new buffer.
1055 	 * Move each member individually to avoid possible store
1056 	 * forwarding stalls and unnecessary copy of skb.
1057 	 */
1058 	new_buf->dma = old_buf->dma;
1059 	new_buf->page = old_buf->page;
1060 	new_buf->page_offset = old_buf->page_offset;
1061 	new_buf->pagecnt_bias = old_buf->pagecnt_bias;
1062 }
1063 
1064 /**
1065  * ice_get_rx_buf - Fetch Rx buffer and synchronize data for use
1066  * @rx_ring: Rx descriptor ring to transact packets on
1067  * @size: size of buffer to add to skb
1068  * @ntc: index of next to clean element
1069  *
1070  * This function will pull an Rx buffer from the ring and synchronize it
1071  * for use by the CPU.
1072  */
1073 static struct ice_rx_buf *
1074 ice_get_rx_buf(struct ice_rx_ring *rx_ring, const unsigned int size,
1075 	       const unsigned int ntc)
1076 {
1077 	struct ice_rx_buf *rx_buf;
1078 
1079 	rx_buf = &rx_ring->rx_buf[ntc];
1080 	prefetchw(rx_buf->page);
1081 
1082 	if (!size)
1083 		return rx_buf;
1084 	/* we are reusing so sync this buffer for CPU use */
1085 	dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
1086 				      rx_buf->page_offset, size,
1087 				      DMA_FROM_DEVICE);
1088 
1089 	/* We have pulled a buffer for use, so decrement pagecnt_bias */
1090 	rx_buf->pagecnt_bias--;
1091 
1092 	return rx_buf;
1093 }
1094 
1095 /**
1096  * ice_get_pgcnts - grab page_count() for gathered fragments
1097  * @rx_ring: Rx descriptor ring to store the page counts on
1098  * @ntc: the next to clean element (not included in this frame!)
1099  *
1100  * This function is intended to be called right before running XDP
1101  * program so that the page recycling mechanism will be able to take
1102  * a correct decision regarding underlying pages; this is done in such
1103  * way as XDP program can change the refcount of page
1104  */
1105 static void ice_get_pgcnts(struct ice_rx_ring *rx_ring, unsigned int ntc)
1106 {
1107 	u32 idx = rx_ring->first_desc;
1108 	struct ice_rx_buf *rx_buf;
1109 	u32 cnt = rx_ring->count;
1110 
1111 	while (idx != ntc) {
1112 		rx_buf = &rx_ring->rx_buf[idx];
1113 		rx_buf->pgcnt = page_count(rx_buf->page);
1114 
1115 		if (++idx == cnt)
1116 			idx = 0;
1117 	}
1118 }
1119 
1120 /**
1121  * ice_build_skb - Build skb around an existing buffer
1122  * @rx_ring: Rx descriptor ring to transact packets on
1123  * @xdp: xdp_buff pointing to the data
1124  *
1125  * This function builds an skb around an existing XDP buffer, taking care
1126  * to set up the skb correctly and avoid any memcpy overhead. Driver has
1127  * already combined frags (if any) to skb_shared_info.
1128  */
1129 static struct sk_buff *
1130 ice_build_skb(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp)
1131 {
1132 	u8 metasize = xdp->data - xdp->data_meta;
1133 	struct skb_shared_info *sinfo = NULL;
1134 	unsigned int nr_frags;
1135 	struct sk_buff *skb;
1136 
1137 	if (unlikely(xdp_buff_has_frags(xdp))) {
1138 		sinfo = xdp_get_shared_info_from_buff(xdp);
1139 		nr_frags = sinfo->nr_frags;
1140 	}
1141 
1142 	/* Prefetch first cache line of first page. If xdp->data_meta
1143 	 * is unused, this points exactly as xdp->data, otherwise we
1144 	 * likely have a consumer accessing first few bytes of meta
1145 	 * data, and then actual data.
1146 	 */
1147 	net_prefetch(xdp->data_meta);
1148 	/* build an skb around the page buffer */
1149 	skb = napi_build_skb(xdp->data_hard_start, xdp->frame_sz);
1150 	if (unlikely(!skb))
1151 		return NULL;
1152 
1153 	/* must to record Rx queue, otherwise OS features such as
1154 	 * symmetric queue won't work
1155 	 */
1156 	skb_record_rx_queue(skb, rx_ring->q_index);
1157 
1158 	/* update pointers within the skb to store the data */
1159 	skb_reserve(skb, xdp->data - xdp->data_hard_start);
1160 	__skb_put(skb, xdp->data_end - xdp->data);
1161 	if (metasize)
1162 		skb_metadata_set(skb, metasize);
1163 
1164 	if (unlikely(xdp_buff_has_frags(xdp)))
1165 		xdp_update_skb_frags_info(skb, nr_frags, sinfo->xdp_frags_size,
1166 					  nr_frags * xdp->frame_sz,
1167 					  xdp_buff_get_skb_flags(xdp));
1168 
1169 	return skb;
1170 }
1171 
1172 /**
1173  * ice_construct_skb - Allocate skb and populate it
1174  * @rx_ring: Rx descriptor ring to transact packets on
1175  * @xdp: xdp_buff pointing to the data
1176  *
1177  * This function allocates an skb. It then populates it with the page
1178  * data from the current receive descriptor, taking care to set up the
1179  * skb correctly.
1180  */
1181 static struct sk_buff *
1182 ice_construct_skb(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp)
1183 {
1184 	unsigned int size = xdp->data_end - xdp->data;
1185 	struct skb_shared_info *sinfo = NULL;
1186 	struct ice_rx_buf *rx_buf;
1187 	unsigned int nr_frags = 0;
1188 	unsigned int headlen;
1189 	struct sk_buff *skb;
1190 
1191 	/* prefetch first cache line of first page */
1192 	net_prefetch(xdp->data);
1193 
1194 	if (unlikely(xdp_buff_has_frags(xdp))) {
1195 		sinfo = xdp_get_shared_info_from_buff(xdp);
1196 		nr_frags = sinfo->nr_frags;
1197 	}
1198 
1199 	/* allocate a skb to store the frags */
1200 	skb = napi_alloc_skb(&rx_ring->q_vector->napi, ICE_RX_HDR_SIZE);
1201 	if (unlikely(!skb))
1202 		return NULL;
1203 
1204 	rx_buf = &rx_ring->rx_buf[rx_ring->first_desc];
1205 	skb_record_rx_queue(skb, rx_ring->q_index);
1206 	/* Determine available headroom for copy */
1207 	headlen = size;
1208 	if (headlen > ICE_RX_HDR_SIZE)
1209 		headlen = eth_get_headlen(skb->dev, xdp->data, ICE_RX_HDR_SIZE);
1210 
1211 	/* align pull length to size of long to optimize memcpy performance */
1212 	memcpy(__skb_put(skb, headlen), xdp->data, ALIGN(headlen,
1213 							 sizeof(long)));
1214 
1215 	/* if we exhaust the linear part then add what is left as a frag */
1216 	size -= headlen;
1217 	if (size) {
1218 		/* besides adding here a partial frag, we are going to add
1219 		 * frags from xdp_buff, make sure there is enough space for
1220 		 * them
1221 		 */
1222 		if (unlikely(nr_frags >= MAX_SKB_FRAGS - 1)) {
1223 			dev_kfree_skb(skb);
1224 			return NULL;
1225 		}
1226 		skb_add_rx_frag(skb, 0, rx_buf->page,
1227 				rx_buf->page_offset + headlen, size,
1228 				xdp->frame_sz);
1229 	} else {
1230 		/* buffer is unused, restore biased page count in Rx buffer;
1231 		 * data was copied onto skb's linear part so there's no
1232 		 * need for adjusting page offset and we can reuse this buffer
1233 		 * as-is
1234 		 */
1235 		rx_buf->pagecnt_bias++;
1236 	}
1237 
1238 	if (unlikely(xdp_buff_has_frags(xdp))) {
1239 		struct skb_shared_info *skinfo = skb_shinfo(skb);
1240 
1241 		memcpy(&skinfo->frags[skinfo->nr_frags], &sinfo->frags[0],
1242 		       sizeof(skb_frag_t) * nr_frags);
1243 
1244 		xdp_update_skb_frags_info(skb, skinfo->nr_frags + nr_frags,
1245 					  sinfo->xdp_frags_size,
1246 					  nr_frags * xdp->frame_sz,
1247 					  xdp_buff_get_skb_flags(xdp));
1248 	}
1249 
1250 	return skb;
1251 }
1252 
1253 /**
1254  * ice_put_rx_buf - Clean up used buffer and either recycle or free
1255  * @rx_ring: Rx descriptor ring to transact packets on
1256  * @rx_buf: Rx buffer to pull data from
1257  *
1258  * This function will clean up the contents of the rx_buf. It will either
1259  * recycle the buffer or unmap it and free the associated resources.
1260  */
1261 static void
1262 ice_put_rx_buf(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf)
1263 {
1264 	if (!rx_buf)
1265 		return;
1266 
1267 	if (ice_can_reuse_rx_page(rx_buf)) {
1268 		/* hand second half of page back to the ring */
1269 		ice_reuse_rx_page(rx_ring, rx_buf);
1270 	} else {
1271 		/* we are not reusing the buffer so unmap it */
1272 		dma_unmap_page_attrs(rx_ring->dev, rx_buf->dma,
1273 				     ice_rx_pg_size(rx_ring), DMA_FROM_DEVICE,
1274 				     ICE_RX_DMA_ATTR);
1275 		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
1276 	}
1277 
1278 	/* clear contents of buffer_info */
1279 	rx_buf->page = NULL;
1280 }
1281 
1282 /**
1283  * ice_put_rx_mbuf - ice_put_rx_buf() caller, for all buffers in frame
1284  * @rx_ring: Rx ring with all the auxiliary data
1285  * @xdp: XDP buffer carrying linear + frags part
1286  * @ntc: the next to clean element (not included in this frame!)
1287  * @verdict: return code from XDP program execution
1288  *
1289  * Called after XDP program is completed, or on error with verdict set to
1290  * ICE_XDP_CONSUMED.
1291  *
1292  * Walk through buffers from first_desc to the end of the frame, releasing
1293  * buffers and satisfying internal page recycle mechanism. The action depends
1294  * on verdict from XDP program.
1295  */
1296 static void ice_put_rx_mbuf(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
1297 			    u32 ntc, u32 verdict)
1298 {
1299 	u32 idx = rx_ring->first_desc;
1300 	u32 cnt = rx_ring->count;
1301 	struct ice_rx_buf *buf;
1302 	u32 xdp_frags = 0;
1303 	int i = 0;
1304 
1305 	if (unlikely(xdp_buff_has_frags(xdp)))
1306 		xdp_frags = xdp_get_shared_info_from_buff(xdp)->nr_frags;
1307 
1308 	while (idx != ntc) {
1309 		buf = &rx_ring->rx_buf[idx];
1310 		if (++idx == cnt)
1311 			idx = 0;
1312 
1313 		/* An XDP program could release fragments from the end of the
1314 		 * buffer. For these, we need to keep the pagecnt_bias as-is.
1315 		 * To do this, only adjust pagecnt_bias for fragments up to
1316 		 * the total remaining after the XDP program has run.
1317 		 */
1318 		if (verdict != ICE_XDP_CONSUMED)
1319 			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);
1320 		else if (i++ <= xdp_frags)
1321 			buf->pagecnt_bias++;
1322 
1323 		ice_put_rx_buf(rx_ring, buf);
1324 	}
1325 
1326 	xdp->data = NULL;
1327 	rx_ring->first_desc = ntc;
1328 }
1329 
1330 /**
1331  * ice_clean_ctrl_rx_irq - Clean descriptors from flow director Rx ring
1332  * @rx_ring: Rx descriptor ring for ctrl_vsi to transact packets on
1333  *
1334  * This function cleans Rx descriptors from the ctrl_vsi Rx ring used
1335  * to set flow director rules on VFs.
1336  */
1337 void ice_clean_ctrl_rx_irq(struct ice_rx_ring *rx_ring)
1338 {
1339 	u32 ntc = rx_ring->next_to_clean;
1340 	unsigned int total_rx_pkts = 0;
1341 	u32 cnt = rx_ring->count;
1342 
1343 	while (likely(total_rx_pkts < ICE_DFLT_IRQ_WORK)) {
1344 		struct ice_vsi *ctrl_vsi = rx_ring->vsi;
1345 		union ice_32b_rx_flex_desc *rx_desc;
1346 		u16 stat_err_bits;
1347 
1348 		rx_desc = ICE_RX_DESC(rx_ring, ntc);
1349 
1350 		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_DD_S);
1351 		if (!ice_test_staterr(rx_desc->wb.status_error0, stat_err_bits))
1352 			break;
1353 
1354 		dma_rmb();
1355 
1356 		if (ctrl_vsi->vf)
1357 			ice_vc_fdir_irq_handler(ctrl_vsi, rx_desc);
1358 
1359 		if (++ntc == cnt)
1360 			ntc = 0;
1361 		total_rx_pkts++;
1362 	}
1363 
1364 	rx_ring->first_desc = ntc;
1365 	rx_ring->next_to_clean = ntc;
1366 	ice_init_ctrl_rx_descs(rx_ring, ICE_RX_DESC_UNUSED(rx_ring));
1367 }
1368 
1369 /**
1370  * ice_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
1371  * @rx_ring: Rx descriptor ring to transact packets on
1372  * @budget: Total limit on number of packets to process
1373  *
1374  * This function provides a "bounce buffer" approach to Rx interrupt
1375  * processing. The advantage to this is that on systems that have
1376  * expensive overhead for IOMMU access this provides a means of avoiding
1377  * it by maintaining the mapping of the page to the system.
1378  *
1379  * Returns amount of work completed
1380  */
1381 static int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget)
1382 {
1383 	unsigned int total_rx_bytes = 0, total_rx_pkts = 0;
1384 	unsigned int offset = rx_ring->rx_offset;
1385 	struct xdp_buff *xdp = &rx_ring->xdp;
1386 	struct ice_tx_ring *xdp_ring = NULL;
1387 	struct bpf_prog *xdp_prog = NULL;
1388 	u32 ntc = rx_ring->next_to_clean;
1389 	u32 cached_ntu, xdp_verdict;
1390 	u32 cnt = rx_ring->count;
1391 	u32 xdp_xmit = 0;
1392 	bool failure;
1393 
1394 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
1395 	if (xdp_prog) {
1396 		xdp_ring = rx_ring->xdp_ring;
1397 		cached_ntu = xdp_ring->next_to_use;
1398 	}
1399 
1400 	/* start the loop to process Rx packets bounded by 'budget' */
1401 	while (likely(total_rx_pkts < (unsigned int)budget)) {
1402 		union ice_32b_rx_flex_desc *rx_desc;
1403 		struct ice_rx_buf *rx_buf;
1404 		struct sk_buff *skb;
1405 		unsigned int size;
1406 		u16 stat_err_bits;
1407 		u16 vlan_tci;
1408 
1409 		/* get the Rx desc from Rx ring based on 'next_to_clean' */
1410 		rx_desc = ICE_RX_DESC(rx_ring, ntc);
1411 
1412 		/* status_error_len will always be zero for unused descriptors
1413 		 * because it's cleared in cleanup, and overlaps with hdr_addr
1414 		 * which is always zero because packet split isn't used, if the
1415 		 * hardware wrote DD then it will be non-zero
1416 		 */
1417 		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_DD_S);
1418 		if (!ice_test_staterr(rx_desc->wb.status_error0, stat_err_bits))
1419 			break;
1420 
1421 		/* This memory barrier is needed to keep us from reading
1422 		 * any other fields out of the rx_desc until we know the
1423 		 * DD bit is set.
1424 		 */
1425 		dma_rmb();
1426 
1427 		ice_trace(clean_rx_irq, rx_ring, rx_desc);
1428 
1429 		size = le16_to_cpu(rx_desc->wb.pkt_len) &
1430 			ICE_RX_FLX_DESC_PKT_LEN_M;
1431 
1432 		/* retrieve a buffer from the ring */
1433 		rx_buf = ice_get_rx_buf(rx_ring, size, ntc);
1434 
1435 		/* Increment ntc before calls to ice_put_rx_mbuf() */
1436 		if (++ntc == cnt)
1437 			ntc = 0;
1438 
1439 		if (!xdp->data) {
1440 			void *hard_start;
1441 
1442 			hard_start = page_address(rx_buf->page) + rx_buf->page_offset -
1443 				     offset;
1444 			xdp_prepare_buff(xdp, hard_start, offset, size, !!offset);
1445 			xdp_buff_clear_frags_flag(xdp);
1446 		} else if (ice_add_xdp_frag(rx_ring, xdp, rx_buf, size)) {
1447 			ice_put_rx_mbuf(rx_ring, xdp, ntc, ICE_XDP_CONSUMED);
1448 			break;
1449 		}
1450 
1451 		/* skip if it is NOP desc */
1452 		if (ice_is_non_eop(rx_ring, rx_desc))
1453 			continue;
1454 
1455 		ice_get_pgcnts(rx_ring, ntc);
1456 		xdp_verdict = ice_run_xdp(rx_ring, xdp, xdp_prog, xdp_ring, rx_desc);
1457 		if (xdp_verdict == ICE_XDP_PASS)
1458 			goto construct_skb;
1459 		total_rx_bytes += xdp_get_buff_len(xdp);
1460 		total_rx_pkts++;
1461 
1462 		ice_put_rx_mbuf(rx_ring, xdp, ntc, xdp_verdict);
1463 		xdp_xmit |= xdp_verdict & (ICE_XDP_TX | ICE_XDP_REDIR);
1464 
1465 		continue;
1466 construct_skb:
1467 		if (likely(ice_ring_uses_build_skb(rx_ring)))
1468 			skb = ice_build_skb(rx_ring, xdp);
1469 		else
1470 			skb = ice_construct_skb(rx_ring, xdp);
1471 		/* exit if we failed to retrieve a buffer */
1472 		if (!skb) {
1473 			rx_ring->ring_stats->rx_stats.alloc_buf_failed++;
1474 			xdp_verdict = ICE_XDP_CONSUMED;
1475 		}
1476 		ice_put_rx_mbuf(rx_ring, xdp, ntc, xdp_verdict);
1477 
1478 		if (!skb)
1479 			break;
1480 
1481 		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_RXE_S);
1482 		if (unlikely(ice_test_staterr(rx_desc->wb.status_error0,
1483 					      stat_err_bits))) {
1484 			dev_kfree_skb_any(skb);
1485 			continue;
1486 		}
1487 
1488 		vlan_tci = ice_get_vlan_tci(rx_desc);
1489 
1490 		/* pad the skb if needed, to make a valid ethernet frame */
1491 		if (eth_skb_pad(skb))
1492 			continue;
1493 
1494 		/* probably a little skewed due to removing CRC */
1495 		total_rx_bytes += skb->len;
1496 
1497 		/* populate checksum, VLAN, and protocol */
1498 		ice_process_skb_fields(rx_ring, rx_desc, skb);
1499 
1500 		ice_trace(clean_rx_irq_indicate, rx_ring, rx_desc, skb);
1501 		/* send completed skb up the stack */
1502 		ice_receive_skb(rx_ring, skb, vlan_tci);
1503 
1504 		/* update budget accounting */
1505 		total_rx_pkts++;
1506 	}
1507 
1508 	rx_ring->next_to_clean = ntc;
1509 	/* return up to cleaned_count buffers to hardware */
1510 	failure = ice_alloc_rx_bufs(rx_ring, ICE_RX_DESC_UNUSED(rx_ring));
1511 
1512 	if (xdp_xmit)
1513 		ice_finalize_xdp_rx(xdp_ring, xdp_xmit, cached_ntu);
1514 
1515 	if (rx_ring->ring_stats)
1516 		ice_update_rx_ring_stats(rx_ring, total_rx_pkts,
1517 					 total_rx_bytes);
1518 
1519 	/* guarantee a trip back through this routine if there was a failure */
1520 	return failure ? budget : (int)total_rx_pkts;
1521 }
1522 
1523 static void __ice_update_sample(struct ice_q_vector *q_vector,
1524 				struct ice_ring_container *rc,
1525 				struct dim_sample *sample,
1526 				bool is_tx)
1527 {
1528 	u64 packets = 0, bytes = 0;
1529 
1530 	if (is_tx) {
1531 		struct ice_tx_ring *tx_ring;
1532 
1533 		ice_for_each_tx_ring(tx_ring, *rc) {
1534 			struct ice_ring_stats *ring_stats;
1535 
1536 			ring_stats = tx_ring->ring_stats;
1537 			if (!ring_stats)
1538 				continue;
1539 			packets += ring_stats->stats.pkts;
1540 			bytes += ring_stats->stats.bytes;
1541 		}
1542 	} else {
1543 		struct ice_rx_ring *rx_ring;
1544 
1545 		ice_for_each_rx_ring(rx_ring, *rc) {
1546 			struct ice_ring_stats *ring_stats;
1547 
1548 			ring_stats = rx_ring->ring_stats;
1549 			if (!ring_stats)
1550 				continue;
1551 			packets += ring_stats->stats.pkts;
1552 			bytes += ring_stats->stats.bytes;
1553 		}
1554 	}
1555 
1556 	dim_update_sample(q_vector->total_events, packets, bytes, sample);
1557 	sample->comp_ctr = 0;
1558 
1559 	/* if dim settings get stale, like when not updated for 1
1560 	 * second or longer, force it to start again. This addresses the
1561 	 * frequent case of an idle queue being switched to by the
1562 	 * scheduler. The 1,000 here means 1,000 milliseconds.
1563 	 */
1564 	if (ktime_ms_delta(sample->time, rc->dim.start_sample.time) >= 1000)
1565 		rc->dim.state = DIM_START_MEASURE;
1566 }
1567 
1568 /**
1569  * ice_net_dim - Update net DIM algorithm
1570  * @q_vector: the vector associated with the interrupt
1571  *
1572  * Create a DIM sample and notify net_dim() so that it can possibly decide
1573  * a new ITR value based on incoming packets, bytes, and interrupts.
1574  *
1575  * This function is a no-op if the ring is not configured to dynamic ITR.
1576  */
1577 static void ice_net_dim(struct ice_q_vector *q_vector)
1578 {
1579 	struct ice_ring_container *tx = &q_vector->tx;
1580 	struct ice_ring_container *rx = &q_vector->rx;
1581 
1582 	if (ITR_IS_DYNAMIC(tx)) {
1583 		struct dim_sample dim_sample;
1584 
1585 		__ice_update_sample(q_vector, tx, &dim_sample, true);
1586 		net_dim(&tx->dim, &dim_sample);
1587 	}
1588 
1589 	if (ITR_IS_DYNAMIC(rx)) {
1590 		struct dim_sample dim_sample;
1591 
1592 		__ice_update_sample(q_vector, rx, &dim_sample, false);
1593 		net_dim(&rx->dim, &dim_sample);
1594 	}
1595 }
1596 
1597 /**
1598  * ice_buildreg_itr - build value for writing to the GLINT_DYN_CTL register
1599  * @itr_idx: interrupt throttling index
1600  * @itr: interrupt throttling value in usecs
1601  */
1602 static u32 ice_buildreg_itr(u16 itr_idx, u16 itr)
1603 {
1604 	/* The ITR value is reported in microseconds, and the register value is
1605 	 * recorded in 2 microsecond units. For this reason we only need to
1606 	 * shift by the GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S to apply this
1607 	 * granularity as a shift instead of division. The mask makes sure the
1608 	 * ITR value is never odd so we don't accidentally write into the field
1609 	 * prior to the ITR field.
1610 	 */
1611 	itr &= ICE_ITR_MASK;
1612 
1613 	return GLINT_DYN_CTL_INTENA_M | GLINT_DYN_CTL_CLEARPBA_M |
1614 		(itr_idx << GLINT_DYN_CTL_ITR_INDX_S) |
1615 		(itr << (GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S));
1616 }
1617 
1618 /**
1619  * ice_enable_interrupt - re-enable MSI-X interrupt
1620  * @q_vector: the vector associated with the interrupt to enable
1621  *
1622  * If the VSI is down, the interrupt will not be re-enabled. Also,
1623  * when enabling the interrupt always reset the wb_on_itr to false
1624  * and trigger a software interrupt to clean out internal state.
1625  */
1626 static void ice_enable_interrupt(struct ice_q_vector *q_vector)
1627 {
1628 	struct ice_vsi *vsi = q_vector->vsi;
1629 	bool wb_en = q_vector->wb_on_itr;
1630 	u32 itr_val;
1631 
1632 	if (test_bit(ICE_DOWN, vsi->state))
1633 		return;
1634 
1635 	/* trigger an ITR delayed software interrupt when exiting busy poll, to
1636 	 * make sure to catch any pending cleanups that might have been missed
1637 	 * due to interrupt state transition. If busy poll or poll isn't
1638 	 * enabled, then don't update ITR, and just enable the interrupt.
1639 	 */
1640 	if (!wb_en) {
1641 		itr_val = ice_buildreg_itr(ICE_ITR_NONE, 0);
1642 	} else {
1643 		q_vector->wb_on_itr = false;
1644 
1645 		/* do two things here with a single write. Set up the third ITR
1646 		 * index to be used for software interrupt moderation, and then
1647 		 * trigger a software interrupt with a rate limit of 20K on
1648 		 * software interrupts, this will help avoid high interrupt
1649 		 * loads due to frequently polling and exiting polling.
1650 		 */
1651 		itr_val = ice_buildreg_itr(ICE_IDX_ITR2, ICE_ITR_20K);
1652 		itr_val |= GLINT_DYN_CTL_SWINT_TRIG_M |
1653 			   ICE_IDX_ITR2 << GLINT_DYN_CTL_SW_ITR_INDX_S |
1654 			   GLINT_DYN_CTL_SW_ITR_INDX_ENA_M;
1655 	}
1656 	wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
1657 }
1658 
1659 /**
1660  * ice_set_wb_on_itr - set WB_ON_ITR for this q_vector
1661  * @q_vector: q_vector to set WB_ON_ITR on
1662  *
1663  * We need to tell hardware to write-back completed descriptors even when
1664  * interrupts are disabled. Descriptors will be written back on cache line
1665  * boundaries without WB_ON_ITR enabled, but if we don't enable WB_ON_ITR
1666  * descriptors may not be written back if they don't fill a cache line until
1667  * the next interrupt.
1668  *
1669  * This sets the write-back frequency to whatever was set previously for the
1670  * ITR indices. Also, set the INTENA_MSK bit to make sure hardware knows we
1671  * aren't meddling with the INTENA_M bit.
1672  */
1673 static void ice_set_wb_on_itr(struct ice_q_vector *q_vector)
1674 {
1675 	struct ice_vsi *vsi = q_vector->vsi;
1676 
1677 	/* already in wb_on_itr mode no need to change it */
1678 	if (q_vector->wb_on_itr)
1679 		return;
1680 
1681 	/* use previously set ITR values for all of the ITR indices by
1682 	 * specifying ICE_ITR_NONE, which will vary in adaptive (AIM) mode and
1683 	 * be static in non-adaptive mode (user configured)
1684 	 */
1685 	wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1686 	     FIELD_PREP(GLINT_DYN_CTL_ITR_INDX_M, ICE_ITR_NONE) |
1687 	     FIELD_PREP(GLINT_DYN_CTL_INTENA_MSK_M, 1) |
1688 	     FIELD_PREP(GLINT_DYN_CTL_WB_ON_ITR_M, 1));
1689 
1690 	q_vector->wb_on_itr = true;
1691 }
1692 
1693 /**
1694  * ice_napi_poll - NAPI polling Rx/Tx cleanup routine
1695  * @napi: napi struct with our devices info in it
1696  * @budget: amount of work driver is allowed to do this pass, in packets
1697  *
1698  * This function will clean all queues associated with a q_vector.
1699  *
1700  * Returns the amount of work done
1701  */
1702 int ice_napi_poll(struct napi_struct *napi, int budget)
1703 {
1704 	struct ice_q_vector *q_vector =
1705 				container_of(napi, struct ice_q_vector, napi);
1706 	struct ice_tx_ring *tx_ring;
1707 	struct ice_rx_ring *rx_ring;
1708 	bool clean_complete = true;
1709 	int budget_per_ring;
1710 	int work_done = 0;
1711 
1712 	/* Since the actual Tx work is minimal, we can give the Tx a larger
1713 	 * budget and be more aggressive about cleaning up the Tx descriptors.
1714 	 */
1715 	ice_for_each_tx_ring(tx_ring, q_vector->tx) {
1716 		struct xsk_buff_pool *xsk_pool = READ_ONCE(tx_ring->xsk_pool);
1717 		bool wd;
1718 
1719 		if (xsk_pool)
1720 			wd = ice_xmit_zc(tx_ring, xsk_pool);
1721 		else if (ice_ring_is_xdp(tx_ring))
1722 			wd = true;
1723 		else
1724 			wd = ice_clean_tx_irq(tx_ring, budget);
1725 
1726 		if (!wd)
1727 			clean_complete = false;
1728 	}
1729 
1730 	/* Handle case where we are called by netpoll with a budget of 0 */
1731 	if (unlikely(budget <= 0))
1732 		return budget;
1733 
1734 	/* normally we have 1 Rx ring per q_vector */
1735 	if (unlikely(q_vector->num_ring_rx > 1))
1736 		/* We attempt to distribute budget to each Rx queue fairly, but
1737 		 * don't allow the budget to go below 1 because that would exit
1738 		 * polling early.
1739 		 */
1740 		budget_per_ring = max_t(int, budget / q_vector->num_ring_rx, 1);
1741 	else
1742 		/* Max of 1 Rx ring in this q_vector so give it the budget */
1743 		budget_per_ring = budget;
1744 
1745 	ice_for_each_rx_ring(rx_ring, q_vector->rx) {
1746 		struct xsk_buff_pool *xsk_pool = READ_ONCE(rx_ring->xsk_pool);
1747 		int cleaned;
1748 
1749 		/* A dedicated path for zero-copy allows making a single
1750 		 * comparison in the irq context instead of many inside the
1751 		 * ice_clean_rx_irq function and makes the codebase cleaner.
1752 		 */
1753 		cleaned = rx_ring->xsk_pool ?
1754 			  ice_clean_rx_irq_zc(rx_ring, xsk_pool, budget_per_ring) :
1755 			  ice_clean_rx_irq(rx_ring, budget_per_ring);
1756 		work_done += cleaned;
1757 		/* if we clean as many as budgeted, we must not be done */
1758 		if (cleaned >= budget_per_ring)
1759 			clean_complete = false;
1760 	}
1761 
1762 	/* If work not completed, return budget and polling will return */
1763 	if (!clean_complete) {
1764 		/* Set the writeback on ITR so partial completions of
1765 		 * cache-lines will still continue even if we're polling.
1766 		 */
1767 		ice_set_wb_on_itr(q_vector);
1768 		return budget;
1769 	}
1770 
1771 	/* Exit the polling mode, but don't re-enable interrupts if stack might
1772 	 * poll us due to busy-polling
1773 	 */
1774 	if (napi_complete_done(napi, work_done)) {
1775 		ice_net_dim(q_vector);
1776 		ice_enable_interrupt(q_vector);
1777 	} else {
1778 		ice_set_wb_on_itr(q_vector);
1779 	}
1780 
1781 	return min_t(int, work_done, budget - 1);
1782 }
1783 
1784 /**
1785  * __ice_maybe_stop_tx - 2nd level check for Tx stop conditions
1786  * @tx_ring: the ring to be checked
1787  * @size: the size buffer we want to assure is available
1788  *
1789  * Returns -EBUSY if a stop is needed, else 0
1790  */
1791 static int __ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
1792 {
1793 	netif_tx_stop_queue(txring_txq(tx_ring));
1794 	/* Memory barrier before checking head and tail */
1795 	smp_mb();
1796 
1797 	/* Check again in a case another CPU has just made room available. */
1798 	if (likely(ICE_DESC_UNUSED(tx_ring) < size))
1799 		return -EBUSY;
1800 
1801 	/* A reprieve! - use start_queue because it doesn't call schedule */
1802 	netif_tx_start_queue(txring_txq(tx_ring));
1803 	++tx_ring->ring_stats->tx_stats.restart_q;
1804 	return 0;
1805 }
1806 
1807 /**
1808  * ice_maybe_stop_tx - 1st level check for Tx stop conditions
1809  * @tx_ring: the ring to be checked
1810  * @size:    the size buffer we want to assure is available
1811  *
1812  * Returns 0 if stop is not needed
1813  */
1814 static int ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
1815 {
1816 	if (likely(ICE_DESC_UNUSED(tx_ring) >= size))
1817 		return 0;
1818 
1819 	return __ice_maybe_stop_tx(tx_ring, size);
1820 }
1821 
1822 /**
1823  * ice_tx_map - Build the Tx descriptor
1824  * @tx_ring: ring to send buffer on
1825  * @first: first buffer info buffer to use
1826  * @off: pointer to struct that holds offload parameters
1827  *
1828  * This function loops over the skb data pointed to by *first
1829  * and gets a physical address for each memory location and programs
1830  * it and the length into the transmit descriptor.
1831  */
1832 static void
1833 ice_tx_map(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first,
1834 	   struct ice_tx_offload_params *off)
1835 {
1836 	u64 td_offset, td_tag, td_cmd;
1837 	u16 i = tx_ring->next_to_use;
1838 	unsigned int data_len, size;
1839 	struct ice_tx_desc *tx_desc;
1840 	struct ice_tx_buf *tx_buf;
1841 	struct sk_buff *skb;
1842 	skb_frag_t *frag;
1843 	dma_addr_t dma;
1844 	bool kick;
1845 
1846 	td_tag = off->td_l2tag1;
1847 	td_cmd = off->td_cmd;
1848 	td_offset = off->td_offset;
1849 	skb = first->skb;
1850 
1851 	data_len = skb->data_len;
1852 	size = skb_headlen(skb);
1853 
1854 	tx_desc = ICE_TX_DESC(tx_ring, i);
1855 
1856 	if (first->tx_flags & ICE_TX_FLAGS_HW_VLAN) {
1857 		td_cmd |= (u64)ICE_TX_DESC_CMD_IL2TAG1;
1858 		td_tag = first->vid;
1859 	}
1860 
1861 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1862 
1863 	tx_buf = first;
1864 
1865 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1866 		unsigned int max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1867 
1868 		if (dma_mapping_error(tx_ring->dev, dma))
1869 			goto dma_error;
1870 
1871 		/* record length, and DMA address */
1872 		dma_unmap_len_set(tx_buf, len, size);
1873 		dma_unmap_addr_set(tx_buf, dma, dma);
1874 
1875 		/* align size to end of page */
1876 		max_data += -dma & (ICE_MAX_READ_REQ_SIZE - 1);
1877 		tx_desc->buf_addr = cpu_to_le64(dma);
1878 
1879 		/* account for data chunks larger than the hardware
1880 		 * can handle
1881 		 */
1882 		while (unlikely(size > ICE_MAX_DATA_PER_TXD)) {
1883 			tx_desc->cmd_type_offset_bsz =
1884 				ice_build_ctob(td_cmd, td_offset, max_data,
1885 					       td_tag);
1886 
1887 			tx_desc++;
1888 			i++;
1889 
1890 			if (i == tx_ring->count) {
1891 				tx_desc = ICE_TX_DESC(tx_ring, 0);
1892 				i = 0;
1893 			}
1894 
1895 			dma += max_data;
1896 			size -= max_data;
1897 
1898 			max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1899 			tx_desc->buf_addr = cpu_to_le64(dma);
1900 		}
1901 
1902 		if (likely(!data_len))
1903 			break;
1904 
1905 		tx_desc->cmd_type_offset_bsz = ice_build_ctob(td_cmd, td_offset,
1906 							      size, td_tag);
1907 
1908 		tx_desc++;
1909 		i++;
1910 
1911 		if (i == tx_ring->count) {
1912 			tx_desc = ICE_TX_DESC(tx_ring, 0);
1913 			i = 0;
1914 		}
1915 
1916 		size = skb_frag_size(frag);
1917 		data_len -= size;
1918 
1919 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1920 				       DMA_TO_DEVICE);
1921 
1922 		tx_buf = &tx_ring->tx_buf[i];
1923 		tx_buf->type = ICE_TX_BUF_FRAG;
1924 	}
1925 
1926 	/* record SW timestamp if HW timestamp is not available */
1927 	skb_tx_timestamp(first->skb);
1928 
1929 	i++;
1930 	if (i == tx_ring->count)
1931 		i = 0;
1932 
1933 	/* write last descriptor with RS and EOP bits */
1934 	td_cmd |= (u64)ICE_TXD_LAST_DESC_CMD;
1935 	tx_desc->cmd_type_offset_bsz =
1936 			ice_build_ctob(td_cmd, td_offset, size, td_tag);
1937 
1938 	/* Force memory writes to complete before letting h/w know there
1939 	 * are new descriptors to fetch.
1940 	 *
1941 	 * We also use this memory barrier to make certain all of the
1942 	 * status bits have been updated before next_to_watch is written.
1943 	 */
1944 	wmb();
1945 
1946 	/* set next_to_watch value indicating a packet is present */
1947 	first->next_to_watch = tx_desc;
1948 
1949 	tx_ring->next_to_use = i;
1950 
1951 	ice_maybe_stop_tx(tx_ring, DESC_NEEDED);
1952 
1953 	/* notify HW of packet */
1954 	kick = __netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount,
1955 				      netdev_xmit_more());
1956 	if (!kick)
1957 		return;
1958 
1959 	if (ice_is_txtime_cfg(tx_ring)) {
1960 		struct ice_tstamp_ring *tstamp_ring = tx_ring->tstamp_ring;
1961 		u32 tstamp_count = tstamp_ring->count;
1962 		u32 j = tstamp_ring->next_to_use;
1963 		struct ice_ts_desc *ts_desc;
1964 		struct timespec64 ts;
1965 		u32 tstamp;
1966 
1967 		ts = ktime_to_timespec64(first->skb->tstamp);
1968 		tstamp = ts.tv_nsec >> ICE_TXTIME_CTX_RESOLUTION_128NS;
1969 
1970 		ts_desc = ICE_TS_DESC(tstamp_ring, j);
1971 		ts_desc->tx_desc_idx_tstamp = ice_build_tstamp_desc(i, tstamp);
1972 
1973 		j++;
1974 		if (j == tstamp_count) {
1975 			u32 fetch = tstamp_count - tx_ring->count;
1976 
1977 			j = 0;
1978 
1979 			/* To prevent an MDD, when wrapping the tstamp ring
1980 			 * create additional TS descriptors equal to the number
1981 			 * of the fetch TS descriptors value. HW will merge the
1982 			 * TS descriptors with the same timestamp value into a
1983 			 * single descriptor.
1984 			 */
1985 			for (; j < fetch; j++) {
1986 				ts_desc = ICE_TS_DESC(tstamp_ring, j);
1987 				ts_desc->tx_desc_idx_tstamp =
1988 				       ice_build_tstamp_desc(i, tstamp);
1989 			}
1990 		}
1991 		tstamp_ring->next_to_use = j;
1992 		writel_relaxed(j, tstamp_ring->tail);
1993 	} else {
1994 		writel_relaxed(i, tx_ring->tail);
1995 	}
1996 	return;
1997 
1998 dma_error:
1999 	/* clear DMA mappings for failed tx_buf map */
2000 	for (;;) {
2001 		tx_buf = &tx_ring->tx_buf[i];
2002 		ice_unmap_and_free_tx_buf(tx_ring, tx_buf);
2003 		if (tx_buf == first)
2004 			break;
2005 		if (i == 0)
2006 			i = tx_ring->count;
2007 		i--;
2008 	}
2009 
2010 	tx_ring->next_to_use = i;
2011 }
2012 
2013 /**
2014  * ice_tx_csum - Enable Tx checksum offloads
2015  * @first: pointer to the first descriptor
2016  * @off: pointer to struct that holds offload parameters
2017  *
2018  * Returns 0 or error (negative) if checksum offload can't happen, 1 otherwise.
2019  */
2020 static
2021 int ice_tx_csum(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2022 {
2023 	const struct ice_tx_ring *tx_ring = off->tx_ring;
2024 	u32 l4_len = 0, l3_len = 0, l2_len = 0;
2025 	struct sk_buff *skb = first->skb;
2026 	union {
2027 		struct iphdr *v4;
2028 		struct ipv6hdr *v6;
2029 		unsigned char *hdr;
2030 	} ip;
2031 	union {
2032 		struct tcphdr *tcp;
2033 		unsigned char *hdr;
2034 	} l4;
2035 	__be16 frag_off, protocol;
2036 	unsigned char *exthdr;
2037 	u32 offset, cmd = 0;
2038 	u8 l4_proto = 0;
2039 
2040 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2041 		return 0;
2042 
2043 	protocol = vlan_get_protocol(skb);
2044 
2045 	if (eth_p_mpls(protocol)) {
2046 		ip.hdr = skb_inner_network_header(skb);
2047 		l4.hdr = skb_checksum_start(skb);
2048 	} else {
2049 		ip.hdr = skb_network_header(skb);
2050 		l4.hdr = skb_transport_header(skb);
2051 	}
2052 
2053 	/* compute outer L2 header size */
2054 	l2_len = ip.hdr - skb->data;
2055 	offset = (l2_len / 2) << ICE_TX_DESC_LEN_MACLEN_S;
2056 
2057 	/* set the tx_flags to indicate the IP protocol type. this is
2058 	 * required so that checksum header computation below is accurate.
2059 	 */
2060 	if (ip.v4->version == 4)
2061 		first->tx_flags |= ICE_TX_FLAGS_IPV4;
2062 	else if (ip.v6->version == 6)
2063 		first->tx_flags |= ICE_TX_FLAGS_IPV6;
2064 
2065 	if (skb->encapsulation) {
2066 		bool gso_ena = false;
2067 		u32 tunnel = 0;
2068 
2069 		/* define outer network header type */
2070 		if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
2071 			tunnel |= (first->tx_flags & ICE_TX_FLAGS_TSO) ?
2072 				  ICE_TX_CTX_EIPT_IPV4 :
2073 				  ICE_TX_CTX_EIPT_IPV4_NO_CSUM;
2074 			l4_proto = ip.v4->protocol;
2075 		} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
2076 			int ret;
2077 
2078 			tunnel |= ICE_TX_CTX_EIPT_IPV6;
2079 			exthdr = ip.hdr + sizeof(*ip.v6);
2080 			l4_proto = ip.v6->nexthdr;
2081 			ret = ipv6_skip_exthdr(skb, exthdr - skb->data,
2082 					       &l4_proto, &frag_off);
2083 			if (ret < 0)
2084 				return -1;
2085 		}
2086 
2087 		/* define outer transport */
2088 		switch (l4_proto) {
2089 		case IPPROTO_UDP:
2090 			tunnel |= ICE_TXD_CTX_UDP_TUNNELING;
2091 			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
2092 			break;
2093 		case IPPROTO_GRE:
2094 			tunnel |= ICE_TXD_CTX_GRE_TUNNELING;
2095 			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
2096 			break;
2097 		case IPPROTO_IPIP:
2098 		case IPPROTO_IPV6:
2099 			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
2100 			l4.hdr = skb_inner_network_header(skb);
2101 			break;
2102 		default:
2103 			if (first->tx_flags & ICE_TX_FLAGS_TSO)
2104 				return -1;
2105 
2106 			skb_checksum_help(skb);
2107 			return 0;
2108 		}
2109 
2110 		/* compute outer L3 header size */
2111 		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
2112 			  ICE_TXD_CTX_QW0_EIPLEN_S;
2113 
2114 		/* switch IP header pointer from outer to inner header */
2115 		ip.hdr = skb_inner_network_header(skb);
2116 
2117 		/* compute tunnel header size */
2118 		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
2119 			   ICE_TXD_CTX_QW0_NATLEN_S;
2120 
2121 		gso_ena = skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL;
2122 		/* indicate if we need to offload outer UDP header */
2123 		if ((first->tx_flags & ICE_TX_FLAGS_TSO) && !gso_ena &&
2124 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
2125 			tunnel |= ICE_TXD_CTX_QW0_L4T_CS_M;
2126 
2127 		/* record tunnel offload values */
2128 		off->cd_tunnel_params |= tunnel;
2129 
2130 		/* set DTYP=1 to indicate that it's an Tx context descriptor
2131 		 * in IPsec tunnel mode with Tx offloads in Quad word 1
2132 		 */
2133 		off->cd_qw1 |= (u64)ICE_TX_DESC_DTYPE_CTX;
2134 
2135 		/* switch L4 header pointer from outer to inner */
2136 		l4.hdr = skb_inner_transport_header(skb);
2137 		l4_proto = 0;
2138 
2139 		/* reset type as we transition from outer to inner headers */
2140 		first->tx_flags &= ~(ICE_TX_FLAGS_IPV4 | ICE_TX_FLAGS_IPV6);
2141 		if (ip.v4->version == 4)
2142 			first->tx_flags |= ICE_TX_FLAGS_IPV4;
2143 		if (ip.v6->version == 6)
2144 			first->tx_flags |= ICE_TX_FLAGS_IPV6;
2145 	}
2146 
2147 	/* Enable IP checksum offloads */
2148 	if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
2149 		l4_proto = ip.v4->protocol;
2150 		/* the stack computes the IP header already, the only time we
2151 		 * need the hardware to recompute it is in the case of TSO.
2152 		 */
2153 		if (first->tx_flags & ICE_TX_FLAGS_TSO)
2154 			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4_CSUM;
2155 		else
2156 			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4;
2157 
2158 	} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
2159 		cmd |= ICE_TX_DESC_CMD_IIPT_IPV6;
2160 		exthdr = ip.hdr + sizeof(*ip.v6);
2161 		l4_proto = ip.v6->nexthdr;
2162 		if (l4.hdr != exthdr)
2163 			ipv6_skip_exthdr(skb, exthdr - skb->data, &l4_proto,
2164 					 &frag_off);
2165 	} else {
2166 		return -1;
2167 	}
2168 
2169 	/* compute inner L3 header size */
2170 	l3_len = l4.hdr - ip.hdr;
2171 	offset |= (l3_len / 4) << ICE_TX_DESC_LEN_IPLEN_S;
2172 
2173 	if ((tx_ring->netdev->features & NETIF_F_HW_CSUM) &&
2174 	    !(first->tx_flags & ICE_TX_FLAGS_TSO) &&
2175 	    !skb_csum_is_sctp(skb)) {
2176 		/* Set GCS */
2177 		u16 csum_start = (skb->csum_start - skb->mac_header) / 2;
2178 		u16 csum_offset = skb->csum_offset / 2;
2179 		u16 gcs_params;
2180 
2181 		gcs_params = FIELD_PREP(ICE_TX_GCS_DESC_START_M, csum_start) |
2182 			     FIELD_PREP(ICE_TX_GCS_DESC_OFFSET_M, csum_offset) |
2183 			     FIELD_PREP(ICE_TX_GCS_DESC_TYPE_M,
2184 					ICE_TX_GCS_DESC_CSUM_PSH);
2185 
2186 		/* Unlike legacy HW checksums, GCS requires a context
2187 		 * descriptor.
2188 		 */
2189 		off->cd_qw1 |= ICE_TX_DESC_DTYPE_CTX;
2190 		off->cd_gcs_params = gcs_params;
2191 		/* Fill out CSO info in data descriptors */
2192 		off->td_offset |= offset;
2193 		off->td_cmd |= cmd;
2194 		return 1;
2195 	}
2196 
2197 	/* Enable L4 checksum offloads */
2198 	switch (l4_proto) {
2199 	case IPPROTO_TCP:
2200 		/* enable checksum offloads */
2201 		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_TCP;
2202 		l4_len = l4.tcp->doff;
2203 		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2204 		break;
2205 	case IPPROTO_UDP:
2206 		/* enable UDP checksum offload */
2207 		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_UDP;
2208 		l4_len = (sizeof(struct udphdr) >> 2);
2209 		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2210 		break;
2211 	case IPPROTO_SCTP:
2212 		/* enable SCTP checksum offload */
2213 		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_SCTP;
2214 		l4_len = sizeof(struct sctphdr) >> 2;
2215 		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2216 		break;
2217 
2218 	default:
2219 		if (first->tx_flags & ICE_TX_FLAGS_TSO)
2220 			return -1;
2221 		skb_checksum_help(skb);
2222 		return 0;
2223 	}
2224 
2225 	off->td_cmd |= cmd;
2226 	off->td_offset |= offset;
2227 	return 1;
2228 }
2229 
2230 /**
2231  * ice_tx_prepare_vlan_flags - prepare generic Tx VLAN tagging flags for HW
2232  * @tx_ring: ring to send buffer on
2233  * @first: pointer to struct ice_tx_buf
2234  *
2235  * Checks the skb and set up correspondingly several generic transmit flags
2236  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2237  */
2238 static void
2239 ice_tx_prepare_vlan_flags(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first)
2240 {
2241 	struct sk_buff *skb = first->skb;
2242 
2243 	/* nothing left to do, software offloaded VLAN */
2244 	if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol))
2245 		return;
2246 
2247 	/* the VLAN ethertype/tpid is determined by VSI configuration and netdev
2248 	 * feature flags, which the driver only allows either 802.1Q or 802.1ad
2249 	 * VLAN offloads exclusively so we only care about the VLAN ID here
2250 	 */
2251 	if (skb_vlan_tag_present(skb)) {
2252 		first->vid = skb_vlan_tag_get(skb);
2253 		if (tx_ring->flags & ICE_TX_FLAGS_RING_VLAN_L2TAG2)
2254 			first->tx_flags |= ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN;
2255 		else
2256 			first->tx_flags |= ICE_TX_FLAGS_HW_VLAN;
2257 	}
2258 
2259 	ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
2260 }
2261 
2262 /**
2263  * ice_tso - computes mss and TSO length to prepare for TSO
2264  * @first: pointer to struct ice_tx_buf
2265  * @off: pointer to struct that holds offload parameters
2266  *
2267  * Returns 0 or error (negative) if TSO can't happen, 1 otherwise.
2268  */
2269 static
2270 int ice_tso(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2271 {
2272 	struct sk_buff *skb = first->skb;
2273 	union {
2274 		struct iphdr *v4;
2275 		struct ipv6hdr *v6;
2276 		unsigned char *hdr;
2277 	} ip;
2278 	union {
2279 		struct tcphdr *tcp;
2280 		struct udphdr *udp;
2281 		unsigned char *hdr;
2282 	} l4;
2283 	u64 cd_mss, cd_tso_len;
2284 	__be16 protocol;
2285 	u32 paylen;
2286 	u8 l4_start;
2287 	int err;
2288 
2289 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2290 		return 0;
2291 
2292 	if (!skb_is_gso(skb))
2293 		return 0;
2294 
2295 	err = skb_cow_head(skb, 0);
2296 	if (err < 0)
2297 		return err;
2298 
2299 	protocol = vlan_get_protocol(skb);
2300 
2301 	if (eth_p_mpls(protocol))
2302 		ip.hdr = skb_inner_network_header(skb);
2303 	else
2304 		ip.hdr = skb_network_header(skb);
2305 	l4.hdr = skb_checksum_start(skb);
2306 
2307 	/* initialize outer IP header fields */
2308 	if (ip.v4->version == 4) {
2309 		ip.v4->tot_len = 0;
2310 		ip.v4->check = 0;
2311 	} else {
2312 		ip.v6->payload_len = 0;
2313 	}
2314 
2315 	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2316 					 SKB_GSO_GRE_CSUM |
2317 					 SKB_GSO_IPXIP4 |
2318 					 SKB_GSO_IPXIP6 |
2319 					 SKB_GSO_UDP_TUNNEL |
2320 					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2321 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2322 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2323 			l4.udp->len = 0;
2324 
2325 			/* determine offset of outer transport header */
2326 			l4_start = (u8)(l4.hdr - skb->data);
2327 
2328 			/* remove payload length from outer checksum */
2329 			paylen = skb->len - l4_start;
2330 			csum_replace_by_diff(&l4.udp->check,
2331 					     (__force __wsum)htonl(paylen));
2332 		}
2333 
2334 		/* reset pointers to inner headers */
2335 		ip.hdr = skb_inner_network_header(skb);
2336 		l4.hdr = skb_inner_transport_header(skb);
2337 
2338 		/* initialize inner IP header fields */
2339 		if (ip.v4->version == 4) {
2340 			ip.v4->tot_len = 0;
2341 			ip.v4->check = 0;
2342 		} else {
2343 			ip.v6->payload_len = 0;
2344 		}
2345 	}
2346 
2347 	/* determine offset of transport header */
2348 	l4_start = (u8)(l4.hdr - skb->data);
2349 
2350 	/* remove payload length from checksum */
2351 	paylen = skb->len - l4_start;
2352 
2353 	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
2354 		csum_replace_by_diff(&l4.udp->check,
2355 				     (__force __wsum)htonl(paylen));
2356 		/* compute length of UDP segmentation header */
2357 		off->header_len = (u8)sizeof(l4.udp) + l4_start;
2358 	} else {
2359 		csum_replace_by_diff(&l4.tcp->check,
2360 				     (__force __wsum)htonl(paylen));
2361 		/* compute length of TCP segmentation header */
2362 		off->header_len = (u8)((l4.tcp->doff * 4) + l4_start);
2363 	}
2364 
2365 	/* update gso_segs and bytecount */
2366 	first->gso_segs = skb_shinfo(skb)->gso_segs;
2367 	first->bytecount += (first->gso_segs - 1) * off->header_len;
2368 
2369 	cd_tso_len = skb->len - off->header_len;
2370 	cd_mss = skb_shinfo(skb)->gso_size;
2371 
2372 	/* record cdesc_qw1 with TSO parameters */
2373 	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2374 			     (ICE_TX_CTX_DESC_TSO << ICE_TXD_CTX_QW1_CMD_S) |
2375 			     (cd_tso_len << ICE_TXD_CTX_QW1_TSO_LEN_S) |
2376 			     (cd_mss << ICE_TXD_CTX_QW1_MSS_S));
2377 	first->tx_flags |= ICE_TX_FLAGS_TSO;
2378 	return 1;
2379 }
2380 
2381 /**
2382  * ice_txd_use_count  - estimate the number of descriptors needed for Tx
2383  * @size: transmit request size in bytes
2384  *
2385  * Due to hardware alignment restrictions (4K alignment), we need to
2386  * assume that we can have no more than 12K of data per descriptor, even
2387  * though each descriptor can take up to 16K - 1 bytes of aligned memory.
2388  * Thus, we need to divide by 12K. But division is slow! Instead,
2389  * we decompose the operation into shifts and one relatively cheap
2390  * multiply operation.
2391  *
2392  * To divide by 12K, we first divide by 4K, then divide by 3:
2393  *     To divide by 4K, shift right by 12 bits
2394  *     To divide by 3, multiply by 85, then divide by 256
2395  *     (Divide by 256 is done by shifting right by 8 bits)
2396  * Finally, we add one to round up. Because 256 isn't an exact multiple of
2397  * 3, we'll underestimate near each multiple of 12K. This is actually more
2398  * accurate as we have 4K - 1 of wiggle room that we can fit into the last
2399  * segment. For our purposes this is accurate out to 1M which is orders of
2400  * magnitude greater than our largest possible GSO size.
2401  *
2402  * This would then be implemented as:
2403  *     return (((size >> 12) * 85) >> 8) + ICE_DESCS_FOR_SKB_DATA_PTR;
2404  *
2405  * Since multiplication and division are commutative, we can reorder
2406  * operations into:
2407  *     return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2408  */
2409 static unsigned int ice_txd_use_count(unsigned int size)
2410 {
2411 	return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2412 }
2413 
2414 /**
2415  * ice_xmit_desc_count - calculate number of Tx descriptors needed
2416  * @skb: send buffer
2417  *
2418  * Returns number of data descriptors needed for this skb.
2419  */
2420 static unsigned int ice_xmit_desc_count(struct sk_buff *skb)
2421 {
2422 	const skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
2423 	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
2424 	unsigned int count = 0, size = skb_headlen(skb);
2425 
2426 	for (;;) {
2427 		count += ice_txd_use_count(size);
2428 
2429 		if (!nr_frags--)
2430 			break;
2431 
2432 		size = skb_frag_size(frag++);
2433 	}
2434 
2435 	return count;
2436 }
2437 
2438 /**
2439  * __ice_chk_linearize - Check if there are more than 8 buffers per packet
2440  * @skb: send buffer
2441  *
2442  * Note: This HW can't DMA more than 8 buffers to build a packet on the wire
2443  * and so we need to figure out the cases where we need to linearize the skb.
2444  *
2445  * For TSO we need to count the TSO header and segment payload separately.
2446  * As such we need to check cases where we have 7 fragments or more as we
2447  * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2448  * the segment payload in the first descriptor, and another 7 for the
2449  * fragments.
2450  */
2451 static bool __ice_chk_linearize(struct sk_buff *skb)
2452 {
2453 	const skb_frag_t *frag, *stale;
2454 	int nr_frags, sum;
2455 
2456 	/* no need to check if number of frags is less than 7 */
2457 	nr_frags = skb_shinfo(skb)->nr_frags;
2458 	if (nr_frags < (ICE_MAX_BUF_TXD - 1))
2459 		return false;
2460 
2461 	/* We need to walk through the list and validate that each group
2462 	 * of 6 fragments totals at least gso_size.
2463 	 */
2464 	nr_frags -= ICE_MAX_BUF_TXD - 2;
2465 	frag = &skb_shinfo(skb)->frags[0];
2466 
2467 	/* Initialize size to the negative value of gso_size minus 1. We
2468 	 * use this as the worst case scenario in which the frag ahead
2469 	 * of us only provides one byte which is why we are limited to 6
2470 	 * descriptors for a single transmit as the header and previous
2471 	 * fragment are already consuming 2 descriptors.
2472 	 */
2473 	sum = 1 - skb_shinfo(skb)->gso_size;
2474 
2475 	/* Add size of frags 0 through 4 to create our initial sum */
2476 	sum += skb_frag_size(frag++);
2477 	sum += skb_frag_size(frag++);
2478 	sum += skb_frag_size(frag++);
2479 	sum += skb_frag_size(frag++);
2480 	sum += skb_frag_size(frag++);
2481 
2482 	/* Walk through fragments adding latest fragment, testing it, and
2483 	 * then removing stale fragments from the sum.
2484 	 */
2485 	for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
2486 		int stale_size = skb_frag_size(stale);
2487 
2488 		sum += skb_frag_size(frag++);
2489 
2490 		/* The stale fragment may present us with a smaller
2491 		 * descriptor than the actual fragment size. To account
2492 		 * for that we need to remove all the data on the front and
2493 		 * figure out what the remainder would be in the last
2494 		 * descriptor associated with the fragment.
2495 		 */
2496 		if (stale_size > ICE_MAX_DATA_PER_TXD) {
2497 			int align_pad = -(skb_frag_off(stale)) &
2498 					(ICE_MAX_READ_REQ_SIZE - 1);
2499 
2500 			sum -= align_pad;
2501 			stale_size -= align_pad;
2502 
2503 			do {
2504 				sum -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2505 				stale_size -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2506 			} while (stale_size > ICE_MAX_DATA_PER_TXD);
2507 		}
2508 
2509 		/* if sum is negative we failed to make sufficient progress */
2510 		if (sum < 0)
2511 			return true;
2512 
2513 		if (!nr_frags--)
2514 			break;
2515 
2516 		sum -= stale_size;
2517 	}
2518 
2519 	return false;
2520 }
2521 
2522 /**
2523  * ice_chk_linearize - Check if there are more than 8 fragments per packet
2524  * @skb:      send buffer
2525  * @count:    number of buffers used
2526  *
2527  * Note: Our HW can't scatter-gather more than 8 fragments to build
2528  * a packet on the wire and so we need to figure out the cases where we
2529  * need to linearize the skb.
2530  */
2531 static bool ice_chk_linearize(struct sk_buff *skb, unsigned int count)
2532 {
2533 	/* Both TSO and single send will work if count is less than 8 */
2534 	if (likely(count < ICE_MAX_BUF_TXD))
2535 		return false;
2536 
2537 	if (skb_is_gso(skb))
2538 		return __ice_chk_linearize(skb);
2539 
2540 	/* we can support up to 8 data buffers for a single send */
2541 	return count != ICE_MAX_BUF_TXD;
2542 }
2543 
2544 /**
2545  * ice_tstamp - set up context descriptor for hardware timestamp
2546  * @tx_ring: pointer to the Tx ring to send buffer on
2547  * @skb: pointer to the SKB we're sending
2548  * @first: Tx buffer
2549  * @off: Tx offload parameters
2550  */
2551 static void
2552 ice_tstamp(struct ice_tx_ring *tx_ring, struct sk_buff *skb,
2553 	   struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2554 {
2555 	s8 idx;
2556 
2557 	/* only timestamp the outbound packet if the user has requested it */
2558 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2559 		return;
2560 
2561 	/* Tx timestamps cannot be sampled when doing TSO */
2562 	if (first->tx_flags & ICE_TX_FLAGS_TSO)
2563 		return;
2564 
2565 	/* Grab an open timestamp slot */
2566 	idx = ice_ptp_request_ts(tx_ring->tx_tstamps, skb);
2567 	if (idx < 0) {
2568 		tx_ring->vsi->back->ptp.tx_hwtstamp_skipped++;
2569 		return;
2570 	}
2571 
2572 	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2573 			     (ICE_TX_CTX_DESC_TSYN << ICE_TXD_CTX_QW1_CMD_S) |
2574 			     ((u64)idx << ICE_TXD_CTX_QW1_TSO_LEN_S));
2575 	first->tx_flags |= ICE_TX_FLAGS_TSYN;
2576 }
2577 
2578 /**
2579  * ice_xmit_frame_ring - Sends buffer on Tx ring
2580  * @skb: send buffer
2581  * @tx_ring: ring to send buffer on
2582  *
2583  * Returns NETDEV_TX_OK if sent, else an error code
2584  */
2585 static netdev_tx_t
2586 ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
2587 {
2588 	struct ice_tx_offload_params offload = { 0 };
2589 	struct ice_vsi *vsi = tx_ring->vsi;
2590 	struct ice_tx_buf *first;
2591 	struct ethhdr *eth;
2592 	unsigned int count;
2593 	int tso, csum;
2594 
2595 	ice_trace(xmit_frame_ring, tx_ring, skb);
2596 
2597 	if (unlikely(ipv6_hopopt_jumbo_remove(skb)))
2598 		goto out_drop;
2599 
2600 	count = ice_xmit_desc_count(skb);
2601 	if (ice_chk_linearize(skb, count)) {
2602 		if (__skb_linearize(skb))
2603 			goto out_drop;
2604 		count = ice_txd_use_count(skb->len);
2605 		tx_ring->ring_stats->tx_stats.tx_linearize++;
2606 	}
2607 
2608 	/* need: 1 descriptor per page * PAGE_SIZE/ICE_MAX_DATA_PER_TXD,
2609 	 *       + 1 desc for skb_head_len/ICE_MAX_DATA_PER_TXD,
2610 	 *       + 4 desc gap to avoid the cache line where head is,
2611 	 *       + 1 desc for context descriptor,
2612 	 * otherwise try next time
2613 	 */
2614 	if (ice_maybe_stop_tx(tx_ring, count + ICE_DESCS_PER_CACHE_LINE +
2615 			      ICE_DESCS_FOR_CTX_DESC)) {
2616 		tx_ring->ring_stats->tx_stats.tx_busy++;
2617 		return NETDEV_TX_BUSY;
2618 	}
2619 
2620 	/* prefetch for bql data which is infrequently used */
2621 	netdev_txq_bql_enqueue_prefetchw(txring_txq(tx_ring));
2622 
2623 	offload.tx_ring = tx_ring;
2624 
2625 	/* record the location of the first descriptor for this packet */
2626 	first = &tx_ring->tx_buf[tx_ring->next_to_use];
2627 	first->skb = skb;
2628 	first->type = ICE_TX_BUF_SKB;
2629 	first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
2630 	first->gso_segs = 1;
2631 	first->tx_flags = 0;
2632 
2633 	/* prepare the VLAN tagging flags for Tx */
2634 	ice_tx_prepare_vlan_flags(tx_ring, first);
2635 	if (first->tx_flags & ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN) {
2636 		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2637 					(ICE_TX_CTX_DESC_IL2TAG2 <<
2638 					ICE_TXD_CTX_QW1_CMD_S));
2639 		offload.cd_l2tag2 = first->vid;
2640 	}
2641 
2642 	/* set up TSO offload */
2643 	tso = ice_tso(first, &offload);
2644 	if (tso < 0)
2645 		goto out_drop;
2646 
2647 	/* always set up Tx checksum offload */
2648 	csum = ice_tx_csum(first, &offload);
2649 	if (csum < 0)
2650 		goto out_drop;
2651 
2652 	/* allow CONTROL frames egress from main VSI if FW LLDP disabled */
2653 	eth = (struct ethhdr *)skb_mac_header(skb);
2654 
2655 	if ((ice_is_switchdev_running(vsi->back) ||
2656 	     ice_lag_is_switchdev_running(vsi->back)) &&
2657 	    vsi->type != ICE_VSI_SF)
2658 		ice_eswitch_set_target_vsi(skb, &offload);
2659 	else if (unlikely((skb->priority == TC_PRIO_CONTROL ||
2660 			   eth->h_proto == htons(ETH_P_LLDP)) &&
2661 			   vsi->type == ICE_VSI_PF &&
2662 			   vsi->port_info->qos_cfg.is_sw_lldp))
2663 		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2664 					ICE_TX_CTX_DESC_SWTCH_UPLINK <<
2665 					ICE_TXD_CTX_QW1_CMD_S);
2666 
2667 	ice_tstamp(tx_ring, skb, first, &offload);
2668 
2669 	if (offload.cd_qw1 & ICE_TX_DESC_DTYPE_CTX) {
2670 		struct ice_tx_ctx_desc *cdesc;
2671 		u16 i = tx_ring->next_to_use;
2672 
2673 		/* grab the next descriptor */
2674 		cdesc = ICE_TX_CTX_DESC(tx_ring, i);
2675 		i++;
2676 		tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2677 
2678 		/* setup context descriptor */
2679 		cdesc->tunneling_params = cpu_to_le32(offload.cd_tunnel_params);
2680 		cdesc->l2tag2 = cpu_to_le16(offload.cd_l2tag2);
2681 		cdesc->gcs = cpu_to_le16(offload.cd_gcs_params);
2682 		cdesc->qw1 = cpu_to_le64(offload.cd_qw1);
2683 	}
2684 
2685 	ice_tx_map(tx_ring, first, &offload);
2686 	return NETDEV_TX_OK;
2687 
2688 out_drop:
2689 	ice_trace(xmit_frame_ring_drop, tx_ring, skb);
2690 	dev_kfree_skb_any(skb);
2691 	return NETDEV_TX_OK;
2692 }
2693 
2694 /**
2695  * ice_start_xmit - Selects the correct VSI and Tx queue to send buffer
2696  * @skb: send buffer
2697  * @netdev: network interface device structure
2698  *
2699  * Returns NETDEV_TX_OK if sent, else an error code
2700  */
2701 netdev_tx_t ice_start_xmit(struct sk_buff *skb, struct net_device *netdev)
2702 {
2703 	struct ice_netdev_priv *np = netdev_priv(netdev);
2704 	struct ice_vsi *vsi = np->vsi;
2705 	struct ice_tx_ring *tx_ring;
2706 
2707 	tx_ring = vsi->tx_rings[skb->queue_mapping];
2708 
2709 	/* hardware can't handle really short frames, hardware padding works
2710 	 * beyond this point
2711 	 */
2712 	if (skb_put_padto(skb, ICE_MIN_TX_LEN))
2713 		return NETDEV_TX_OK;
2714 
2715 	return ice_xmit_frame_ring(skb, tx_ring);
2716 }
2717 
2718 /**
2719  * ice_get_dscp_up - return the UP/TC value for a SKB
2720  * @dcbcfg: DCB config that contains DSCP to UP/TC mapping
2721  * @skb: SKB to query for info to determine UP/TC
2722  *
2723  * This function is to only be called when the PF is in L3 DSCP PFC mode
2724  */
2725 static u8 ice_get_dscp_up(struct ice_dcbx_cfg *dcbcfg, struct sk_buff *skb)
2726 {
2727 	u8 dscp = 0;
2728 
2729 	if (skb->protocol == htons(ETH_P_IP))
2730 		dscp = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
2731 	else if (skb->protocol == htons(ETH_P_IPV6))
2732 		dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
2733 
2734 	return dcbcfg->dscp_map[dscp];
2735 }
2736 
2737 u16
2738 ice_select_queue(struct net_device *netdev, struct sk_buff *skb,
2739 		 struct net_device *sb_dev)
2740 {
2741 	struct ice_pf *pf = ice_netdev_to_pf(netdev);
2742 	struct ice_dcbx_cfg *dcbcfg;
2743 
2744 	dcbcfg = &pf->hw.port_info->qos_cfg.local_dcbx_cfg;
2745 	if (dcbcfg->pfc_mode == ICE_QOS_MODE_DSCP)
2746 		skb->priority = ice_get_dscp_up(dcbcfg, skb);
2747 
2748 	return netdev_pick_tx(netdev, skb, sb_dev);
2749 }
2750 
2751 /**
2752  * ice_clean_ctrl_tx_irq - interrupt handler for flow director Tx queue
2753  * @tx_ring: tx_ring to clean
2754  */
2755 void ice_clean_ctrl_tx_irq(struct ice_tx_ring *tx_ring)
2756 {
2757 	struct ice_vsi *vsi = tx_ring->vsi;
2758 	s16 i = tx_ring->next_to_clean;
2759 	int budget = ICE_DFLT_IRQ_WORK;
2760 	struct ice_tx_desc *tx_desc;
2761 	struct ice_tx_buf *tx_buf;
2762 
2763 	tx_buf = &tx_ring->tx_buf[i];
2764 	tx_desc = ICE_TX_DESC(tx_ring, i);
2765 	i -= tx_ring->count;
2766 
2767 	do {
2768 		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
2769 
2770 		/* if next_to_watch is not set then there is no pending work */
2771 		if (!eop_desc)
2772 			break;
2773 
2774 		/* prevent any other reads prior to eop_desc */
2775 		smp_rmb();
2776 
2777 		/* if the descriptor isn't done, no work to do */
2778 		if (!(eop_desc->cmd_type_offset_bsz &
2779 		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
2780 			break;
2781 
2782 		/* clear next_to_watch to prevent false hangs */
2783 		tx_buf->next_to_watch = NULL;
2784 		tx_desc->buf_addr = 0;
2785 		tx_desc->cmd_type_offset_bsz = 0;
2786 
2787 		/* move past filter desc */
2788 		tx_buf++;
2789 		tx_desc++;
2790 		i++;
2791 		if (unlikely(!i)) {
2792 			i -= tx_ring->count;
2793 			tx_buf = tx_ring->tx_buf;
2794 			tx_desc = ICE_TX_DESC(tx_ring, 0);
2795 		}
2796 
2797 		/* unmap the data header */
2798 		if (dma_unmap_len(tx_buf, len))
2799 			dma_unmap_single(tx_ring->dev,
2800 					 dma_unmap_addr(tx_buf, dma),
2801 					 dma_unmap_len(tx_buf, len),
2802 					 DMA_TO_DEVICE);
2803 		if (tx_buf->type == ICE_TX_BUF_DUMMY)
2804 			devm_kfree(tx_ring->dev, tx_buf->raw_buf);
2805 
2806 		/* clear next_to_watch to prevent false hangs */
2807 		tx_buf->type = ICE_TX_BUF_EMPTY;
2808 		tx_buf->tx_flags = 0;
2809 		tx_buf->next_to_watch = NULL;
2810 		dma_unmap_len_set(tx_buf, len, 0);
2811 		tx_desc->buf_addr = 0;
2812 		tx_desc->cmd_type_offset_bsz = 0;
2813 
2814 		/* move past eop_desc for start of next FD desc */
2815 		tx_buf++;
2816 		tx_desc++;
2817 		i++;
2818 		if (unlikely(!i)) {
2819 			i -= tx_ring->count;
2820 			tx_buf = tx_ring->tx_buf;
2821 			tx_desc = ICE_TX_DESC(tx_ring, 0);
2822 		}
2823 
2824 		budget--;
2825 	} while (likely(budget));
2826 
2827 	i += tx_ring->count;
2828 	tx_ring->next_to_clean = i;
2829 
2830 	/* re-enable interrupt if needed */
2831 	ice_irq_dynamic_ena(&vsi->back->hw, vsi, vsi->q_vectors[0]);
2832 }
2833