xref: /linux/drivers/net/ethernet/intel/ice/ice_txrx.c (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
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 FDIR_DESC_RXDID 0x40
24 #define ICE_FDIR_CLEAN_DELAY 10
25 
26 /**
27  * ice_prgm_fdir_fltr - Program a Flow Director filter
28  * @vsi: VSI to send dummy packet
29  * @fdir_desc: flow director descriptor
30  * @raw_packet: allocated buffer for flow director
31  */
32 int
33 ice_prgm_fdir_fltr(struct ice_vsi *vsi, struct ice_fltr_desc *fdir_desc,
34 		   u8 *raw_packet)
35 {
36 	struct ice_tx_buf *tx_buf, *first;
37 	struct ice_fltr_desc *f_desc;
38 	struct ice_tx_desc *tx_desc;
39 	struct ice_tx_ring *tx_ring;
40 	struct device *dev;
41 	dma_addr_t dma;
42 	u32 td_cmd;
43 	u16 i;
44 
45 	/* VSI and Tx ring */
46 	if (!vsi)
47 		return -ENOENT;
48 	tx_ring = vsi->tx_rings[0];
49 	if (!tx_ring || !tx_ring->desc)
50 		return -ENOENT;
51 	dev = tx_ring->dev;
52 
53 	/* we are using two descriptors to add/del a filter and we can wait */
54 	for (i = ICE_FDIR_CLEAN_DELAY; ICE_DESC_UNUSED(tx_ring) < 2; i--) {
55 		if (!i)
56 			return -EAGAIN;
57 		msleep_interruptible(1);
58 	}
59 
60 	dma = dma_map_single(dev, raw_packet, ICE_FDIR_MAX_RAW_PKT_SIZE,
61 			     DMA_TO_DEVICE);
62 
63 	if (dma_mapping_error(dev, dma))
64 		return -EINVAL;
65 
66 	/* grab the next descriptor */
67 	i = tx_ring->next_to_use;
68 	first = &tx_ring->tx_buf[i];
69 	f_desc = ICE_TX_FDIRDESC(tx_ring, i);
70 	memcpy(f_desc, fdir_desc, sizeof(*f_desc));
71 
72 	i++;
73 	i = (i < tx_ring->count) ? i : 0;
74 	tx_desc = ICE_TX_DESC(tx_ring, i);
75 	tx_buf = &tx_ring->tx_buf[i];
76 
77 	i++;
78 	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
79 
80 	memset(tx_buf, 0, sizeof(*tx_buf));
81 	dma_unmap_len_set(tx_buf, len, ICE_FDIR_MAX_RAW_PKT_SIZE);
82 	dma_unmap_addr_set(tx_buf, dma, dma);
83 
84 	tx_desc->buf_addr = cpu_to_le64(dma);
85 	td_cmd = ICE_TXD_LAST_DESC_CMD | ICE_TX_DESC_CMD_DUMMY |
86 		 ICE_TX_DESC_CMD_RE;
87 
88 	tx_buf->type = ICE_TX_BUF_DUMMY;
89 	tx_buf->raw_buf = raw_packet;
90 
91 	tx_desc->cmd_type_offset_bsz =
92 		ice_build_ctob(td_cmd, 0, ICE_FDIR_MAX_RAW_PKT_SIZE, 0);
93 
94 	/* Force memory write to complete before letting h/w know
95 	 * there are new descriptors to fetch.
96 	 */
97 	wmb();
98 
99 	/* mark the data descriptor to be watched */
100 	first->next_to_watch = tx_desc;
101 
102 	writel(tx_ring->next_to_use, tx_ring->tail);
103 
104 	return 0;
105 }
106 
107 /**
108  * ice_unmap_and_free_tx_buf - Release a Tx buffer
109  * @ring: the ring that owns the buffer
110  * @tx_buf: the buffer to free
111  */
112 static void
113 ice_unmap_and_free_tx_buf(struct ice_tx_ring *ring, struct ice_tx_buf *tx_buf)
114 {
115 	if (dma_unmap_len(tx_buf, len))
116 		dma_unmap_page(ring->dev,
117 			       dma_unmap_addr(tx_buf, dma),
118 			       dma_unmap_len(tx_buf, len),
119 			       DMA_TO_DEVICE);
120 
121 	switch (tx_buf->type) {
122 	case ICE_TX_BUF_DUMMY:
123 		devm_kfree(ring->dev, tx_buf->raw_buf);
124 		break;
125 	case ICE_TX_BUF_SKB:
126 		dev_kfree_skb_any(tx_buf->skb);
127 		break;
128 	case ICE_TX_BUF_XDP_TX:
129 		page_frag_free(tx_buf->raw_buf);
130 		break;
131 	case ICE_TX_BUF_XDP_XMIT:
132 		xdp_return_frame(tx_buf->xdpf);
133 		break;
134 	}
135 
136 	tx_buf->next_to_watch = NULL;
137 	tx_buf->type = ICE_TX_BUF_EMPTY;
138 	dma_unmap_len_set(tx_buf, len, 0);
139 	/* tx_buf must be completely set up in the transmit path */
140 }
141 
142 static struct netdev_queue *txring_txq(const struct ice_tx_ring *ring)
143 {
144 	return netdev_get_tx_queue(ring->netdev, ring->q_index);
145 }
146 
147 /**
148  * ice_clean_tx_ring - Free any empty Tx buffers
149  * @tx_ring: ring to be cleaned
150  */
151 void ice_clean_tx_ring(struct ice_tx_ring *tx_ring)
152 {
153 	u32 size;
154 	u16 i;
155 
156 	if (ice_ring_is_xdp(tx_ring) && tx_ring->xsk_pool) {
157 		ice_xsk_clean_xdp_ring(tx_ring);
158 		goto tx_skip_free;
159 	}
160 
161 	/* ring already cleared, nothing to do */
162 	if (!tx_ring->tx_buf)
163 		return;
164 
165 	/* Free all the Tx ring sk_buffs */
166 	for (i = 0; i < tx_ring->count; i++)
167 		ice_unmap_and_free_tx_buf(tx_ring, &tx_ring->tx_buf[i]);
168 
169 tx_skip_free:
170 	memset(tx_ring->tx_buf, 0, sizeof(*tx_ring->tx_buf) * tx_ring->count);
171 
172 	size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
173 		     PAGE_SIZE);
174 	/* Zero out the descriptor ring */
175 	memset(tx_ring->desc, 0, size);
176 
177 	tx_ring->next_to_use = 0;
178 	tx_ring->next_to_clean = 0;
179 
180 	if (!tx_ring->netdev)
181 		return;
182 
183 	/* cleanup Tx queue statistics */
184 	netdev_tx_reset_queue(txring_txq(tx_ring));
185 }
186 
187 /**
188  * ice_free_tx_ring - Free Tx resources per queue
189  * @tx_ring: Tx descriptor ring for a specific queue
190  *
191  * Free all transmit software resources
192  */
193 void ice_free_tx_ring(struct ice_tx_ring *tx_ring)
194 {
195 	u32 size;
196 
197 	ice_clean_tx_ring(tx_ring);
198 	devm_kfree(tx_ring->dev, tx_ring->tx_buf);
199 	tx_ring->tx_buf = NULL;
200 
201 	if (tx_ring->desc) {
202 		size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
203 			     PAGE_SIZE);
204 		dmam_free_coherent(tx_ring->dev, size,
205 				   tx_ring->desc, tx_ring->dma);
206 		tx_ring->desc = NULL;
207 	}
208 }
209 
210 /**
211  * ice_clean_tx_irq - Reclaim resources after transmit completes
212  * @tx_ring: Tx ring to clean
213  * @napi_budget: Used to determine if we are in netpoll
214  *
215  * Returns true if there's any budget left (e.g. the clean is finished)
216  */
217 static bool ice_clean_tx_irq(struct ice_tx_ring *tx_ring, int napi_budget)
218 {
219 	unsigned int total_bytes = 0, total_pkts = 0;
220 	unsigned int budget = ICE_DFLT_IRQ_WORK;
221 	struct ice_vsi *vsi = tx_ring->vsi;
222 	s16 i = tx_ring->next_to_clean;
223 	struct ice_tx_desc *tx_desc;
224 	struct ice_tx_buf *tx_buf;
225 
226 	/* get the bql data ready */
227 	netdev_txq_bql_complete_prefetchw(txring_txq(tx_ring));
228 
229 	tx_buf = &tx_ring->tx_buf[i];
230 	tx_desc = ICE_TX_DESC(tx_ring, i);
231 	i -= tx_ring->count;
232 
233 	prefetch(&vsi->state);
234 
235 	do {
236 		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
237 
238 		/* if next_to_watch is not set then there is no work pending */
239 		if (!eop_desc)
240 			break;
241 
242 		/* follow the guidelines of other drivers */
243 		prefetchw(&tx_buf->skb->users);
244 
245 		smp_rmb();	/* prevent any other reads prior to eop_desc */
246 
247 		ice_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
248 		/* if the descriptor isn't done, no work yet to do */
249 		if (!(eop_desc->cmd_type_offset_bsz &
250 		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
251 			break;
252 
253 		/* clear next_to_watch to prevent false hangs */
254 		tx_buf->next_to_watch = NULL;
255 
256 		/* update the statistics for this packet */
257 		total_bytes += tx_buf->bytecount;
258 		total_pkts += tx_buf->gso_segs;
259 
260 		/* free the skb */
261 		napi_consume_skb(tx_buf->skb, napi_budget);
262 
263 		/* unmap skb header data */
264 		dma_unmap_single(tx_ring->dev,
265 				 dma_unmap_addr(tx_buf, dma),
266 				 dma_unmap_len(tx_buf, len),
267 				 DMA_TO_DEVICE);
268 
269 		/* clear tx_buf data */
270 		tx_buf->type = ICE_TX_BUF_EMPTY;
271 		dma_unmap_len_set(tx_buf, len, 0);
272 
273 		/* unmap remaining buffers */
274 		while (tx_desc != eop_desc) {
275 			ice_trace(clean_tx_irq_unmap, tx_ring, tx_desc, tx_buf);
276 			tx_buf++;
277 			tx_desc++;
278 			i++;
279 			if (unlikely(!i)) {
280 				i -= tx_ring->count;
281 				tx_buf = tx_ring->tx_buf;
282 				tx_desc = ICE_TX_DESC(tx_ring, 0);
283 			}
284 
285 			/* unmap any remaining paged data */
286 			if (dma_unmap_len(tx_buf, len)) {
287 				dma_unmap_page(tx_ring->dev,
288 					       dma_unmap_addr(tx_buf, dma),
289 					       dma_unmap_len(tx_buf, len),
290 					       DMA_TO_DEVICE);
291 				dma_unmap_len_set(tx_buf, len, 0);
292 			}
293 		}
294 		ice_trace(clean_tx_irq_unmap_eop, tx_ring, tx_desc, tx_buf);
295 
296 		/* move us one more past the eop_desc for start of next pkt */
297 		tx_buf++;
298 		tx_desc++;
299 		i++;
300 		if (unlikely(!i)) {
301 			i -= tx_ring->count;
302 			tx_buf = tx_ring->tx_buf;
303 			tx_desc = ICE_TX_DESC(tx_ring, 0);
304 		}
305 
306 		prefetch(tx_desc);
307 
308 		/* update budget accounting */
309 		budget--;
310 	} while (likely(budget));
311 
312 	i += tx_ring->count;
313 	tx_ring->next_to_clean = i;
314 
315 	ice_update_tx_ring_stats(tx_ring, total_pkts, total_bytes);
316 	netdev_tx_completed_queue(txring_txq(tx_ring), total_pkts, total_bytes);
317 
318 #define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
319 	if (unlikely(total_pkts && netif_carrier_ok(tx_ring->netdev) &&
320 		     (ICE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
321 		/* Make sure that anybody stopping the queue after this
322 		 * sees the new next_to_clean.
323 		 */
324 		smp_mb();
325 		if (netif_tx_queue_stopped(txring_txq(tx_ring)) &&
326 		    !test_bit(ICE_VSI_DOWN, vsi->state)) {
327 			netif_tx_wake_queue(txring_txq(tx_ring));
328 			++tx_ring->ring_stats->tx_stats.restart_q;
329 		}
330 	}
331 
332 	return !!budget;
333 }
334 
335 /**
336  * ice_setup_tx_ring - Allocate the Tx descriptors
337  * @tx_ring: the Tx ring to set up
338  *
339  * Return 0 on success, negative on error
340  */
341 int ice_setup_tx_ring(struct ice_tx_ring *tx_ring)
342 {
343 	struct device *dev = tx_ring->dev;
344 	u32 size;
345 
346 	if (!dev)
347 		return -ENOMEM;
348 
349 	/* warn if we are about to overwrite the pointer */
350 	WARN_ON(tx_ring->tx_buf);
351 	tx_ring->tx_buf =
352 		devm_kcalloc(dev, sizeof(*tx_ring->tx_buf), tx_ring->count,
353 			     GFP_KERNEL);
354 	if (!tx_ring->tx_buf)
355 		return -ENOMEM;
356 
357 	/* round up to nearest page */
358 	size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
359 		     PAGE_SIZE);
360 	tx_ring->desc = dmam_alloc_coherent(dev, size, &tx_ring->dma,
361 					    GFP_KERNEL);
362 	if (!tx_ring->desc) {
363 		dev_err(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
364 			size);
365 		goto err;
366 	}
367 
368 	tx_ring->next_to_use = 0;
369 	tx_ring->next_to_clean = 0;
370 	tx_ring->ring_stats->tx_stats.prev_pkt = -1;
371 	return 0;
372 
373 err:
374 	devm_kfree(dev, tx_ring->tx_buf);
375 	tx_ring->tx_buf = NULL;
376 	return -ENOMEM;
377 }
378 
379 /**
380  * ice_clean_rx_ring - Free Rx buffers
381  * @rx_ring: ring to be cleaned
382  */
383 void ice_clean_rx_ring(struct ice_rx_ring *rx_ring)
384 {
385 	struct xdp_buff *xdp = &rx_ring->xdp;
386 	struct device *dev = rx_ring->dev;
387 	u32 size;
388 	u16 i;
389 
390 	/* ring already cleared, nothing to do */
391 	if (!rx_ring->rx_buf)
392 		return;
393 
394 	if (rx_ring->xsk_pool) {
395 		ice_xsk_clean_rx_ring(rx_ring);
396 		goto rx_skip_free;
397 	}
398 
399 	if (xdp->data) {
400 		xdp_return_buff(xdp);
401 		xdp->data = NULL;
402 	}
403 
404 	/* Free all the Rx ring sk_buffs */
405 	for (i = 0; i < rx_ring->count; i++) {
406 		struct ice_rx_buf *rx_buf = &rx_ring->rx_buf[i];
407 
408 		if (!rx_buf->page)
409 			continue;
410 
411 		/* Invalidate cache lines that may have been written to by
412 		 * device so that we avoid corrupting memory.
413 		 */
414 		dma_sync_single_range_for_cpu(dev, rx_buf->dma,
415 					      rx_buf->page_offset,
416 					      rx_ring->rx_buf_len,
417 					      DMA_FROM_DEVICE);
418 
419 		/* free resources associated with mapping */
420 		dma_unmap_page_attrs(dev, rx_buf->dma, ice_rx_pg_size(rx_ring),
421 				     DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
422 		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
423 
424 		rx_buf->page = NULL;
425 		rx_buf->page_offset = 0;
426 	}
427 
428 rx_skip_free:
429 	if (rx_ring->xsk_pool)
430 		memset(rx_ring->xdp_buf, 0, array_size(rx_ring->count, sizeof(*rx_ring->xdp_buf)));
431 	else
432 		memset(rx_ring->rx_buf, 0, array_size(rx_ring->count, sizeof(*rx_ring->rx_buf)));
433 
434 	/* Zero out the descriptor ring */
435 	size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
436 		     PAGE_SIZE);
437 	memset(rx_ring->desc, 0, size);
438 
439 	rx_ring->next_to_alloc = 0;
440 	rx_ring->next_to_clean = 0;
441 	rx_ring->first_desc = 0;
442 	rx_ring->next_to_use = 0;
443 }
444 
445 /**
446  * ice_free_rx_ring - Free Rx resources
447  * @rx_ring: ring to clean the resources from
448  *
449  * Free all receive software resources
450  */
451 void ice_free_rx_ring(struct ice_rx_ring *rx_ring)
452 {
453 	u32 size;
454 
455 	ice_clean_rx_ring(rx_ring);
456 	if (rx_ring->vsi->type == ICE_VSI_PF)
457 		if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
458 			xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
459 	rx_ring->xdp_prog = NULL;
460 	if (rx_ring->xsk_pool) {
461 		kfree(rx_ring->xdp_buf);
462 		rx_ring->xdp_buf = NULL;
463 	} else {
464 		kfree(rx_ring->rx_buf);
465 		rx_ring->rx_buf = NULL;
466 	}
467 
468 	if (rx_ring->desc) {
469 		size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
470 			     PAGE_SIZE);
471 		dmam_free_coherent(rx_ring->dev, size,
472 				   rx_ring->desc, rx_ring->dma);
473 		rx_ring->desc = NULL;
474 	}
475 }
476 
477 /**
478  * ice_setup_rx_ring - Allocate the Rx descriptors
479  * @rx_ring: the Rx ring to set up
480  *
481  * Return 0 on success, negative on error
482  */
483 int ice_setup_rx_ring(struct ice_rx_ring *rx_ring)
484 {
485 	struct device *dev = rx_ring->dev;
486 	u32 size;
487 
488 	if (!dev)
489 		return -ENOMEM;
490 
491 	/* warn if we are about to overwrite the pointer */
492 	WARN_ON(rx_ring->rx_buf);
493 	rx_ring->rx_buf =
494 		kcalloc(rx_ring->count, sizeof(*rx_ring->rx_buf), GFP_KERNEL);
495 	if (!rx_ring->rx_buf)
496 		return -ENOMEM;
497 
498 	/* round up to nearest page */
499 	size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
500 		     PAGE_SIZE);
501 	rx_ring->desc = dmam_alloc_coherent(dev, size, &rx_ring->dma,
502 					    GFP_KERNEL);
503 	if (!rx_ring->desc) {
504 		dev_err(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
505 			size);
506 		goto err;
507 	}
508 
509 	rx_ring->next_to_use = 0;
510 	rx_ring->next_to_clean = 0;
511 	rx_ring->first_desc = 0;
512 
513 	if (ice_is_xdp_ena_vsi(rx_ring->vsi))
514 		WRITE_ONCE(rx_ring->xdp_prog, rx_ring->vsi->xdp_prog);
515 
516 	return 0;
517 
518 err:
519 	kfree(rx_ring->rx_buf);
520 	rx_ring->rx_buf = NULL;
521 	return -ENOMEM;
522 }
523 
524 /**
525  * ice_rx_frame_truesize
526  * @rx_ring: ptr to Rx ring
527  * @size: size
528  *
529  * calculate the truesize with taking into the account PAGE_SIZE of
530  * underlying arch
531  */
532 static unsigned int
533 ice_rx_frame_truesize(struct ice_rx_ring *rx_ring, const unsigned int size)
534 {
535 	unsigned int truesize;
536 
537 #if (PAGE_SIZE < 8192)
538 	truesize = ice_rx_pg_size(rx_ring) / 2; /* Must be power-of-2 */
539 #else
540 	truesize = rx_ring->rx_offset ?
541 		SKB_DATA_ALIGN(rx_ring->rx_offset + size) +
542 		SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) :
543 		SKB_DATA_ALIGN(size);
544 #endif
545 	return truesize;
546 }
547 
548 /**
549  * ice_run_xdp - Executes an XDP program on initialized xdp_buff
550  * @rx_ring: Rx ring
551  * @xdp: xdp_buff used as input to the XDP program
552  * @xdp_prog: XDP program to run
553  * @xdp_ring: ring to be used for XDP_TX action
554  * @rx_buf: Rx buffer to store the XDP action
555  * @eop_desc: Last descriptor in packet to read metadata from
556  *
557  * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR}
558  */
559 static void
560 ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
561 	    struct bpf_prog *xdp_prog, struct ice_tx_ring *xdp_ring,
562 	    struct ice_rx_buf *rx_buf, union ice_32b_rx_flex_desc *eop_desc)
563 {
564 	unsigned int ret = ICE_XDP_PASS;
565 	u32 act;
566 
567 	if (!xdp_prog)
568 		goto exit;
569 
570 	ice_xdp_meta_set_desc(xdp, eop_desc);
571 
572 	act = bpf_prog_run_xdp(xdp_prog, xdp);
573 	switch (act) {
574 	case XDP_PASS:
575 		break;
576 	case XDP_TX:
577 		if (static_branch_unlikely(&ice_xdp_locking_key))
578 			spin_lock(&xdp_ring->tx_lock);
579 		ret = __ice_xmit_xdp_ring(xdp, xdp_ring, false);
580 		if (static_branch_unlikely(&ice_xdp_locking_key))
581 			spin_unlock(&xdp_ring->tx_lock);
582 		if (ret == ICE_XDP_CONSUMED)
583 			goto out_failure;
584 		break;
585 	case XDP_REDIRECT:
586 		if (xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog))
587 			goto out_failure;
588 		ret = ICE_XDP_REDIR;
589 		break;
590 	default:
591 		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
592 		fallthrough;
593 	case XDP_ABORTED:
594 out_failure:
595 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
596 		fallthrough;
597 	case XDP_DROP:
598 		ret = ICE_XDP_CONSUMED;
599 	}
600 exit:
601 	ice_set_rx_bufs_act(xdp, rx_ring, ret);
602 }
603 
604 /**
605  * ice_xmit_xdp_ring - submit frame to XDP ring for transmission
606  * @xdpf: XDP frame that will be converted to XDP buff
607  * @xdp_ring: XDP ring for transmission
608  */
609 static int ice_xmit_xdp_ring(const struct xdp_frame *xdpf,
610 			     struct ice_tx_ring *xdp_ring)
611 {
612 	struct xdp_buff xdp;
613 
614 	xdp.data_hard_start = (void *)xdpf;
615 	xdp.data = xdpf->data;
616 	xdp.data_end = xdp.data + xdpf->len;
617 	xdp.frame_sz = xdpf->frame_sz;
618 	xdp.flags = xdpf->flags;
619 
620 	return __ice_xmit_xdp_ring(&xdp, xdp_ring, true);
621 }
622 
623 /**
624  * ice_xdp_xmit - submit packets to XDP ring for transmission
625  * @dev: netdev
626  * @n: number of XDP frames to be transmitted
627  * @frames: XDP frames to be transmitted
628  * @flags: transmit flags
629  *
630  * Returns number of frames successfully sent. Failed frames
631  * will be free'ed by XDP core.
632  * For error cases, a negative errno code is returned and no-frames
633  * are transmitted (caller must handle freeing frames).
634  */
635 int
636 ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
637 	     u32 flags)
638 {
639 	struct ice_netdev_priv *np = netdev_priv(dev);
640 	unsigned int queue_index = smp_processor_id();
641 	struct ice_vsi *vsi = np->vsi;
642 	struct ice_tx_ring *xdp_ring;
643 	struct ice_tx_buf *tx_buf;
644 	int nxmit = 0, i;
645 
646 	if (test_bit(ICE_VSI_DOWN, vsi->state))
647 		return -ENETDOWN;
648 
649 	if (!ice_is_xdp_ena_vsi(vsi))
650 		return -ENXIO;
651 
652 	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
653 		return -EINVAL;
654 
655 	if (static_branch_unlikely(&ice_xdp_locking_key)) {
656 		queue_index %= vsi->num_xdp_txq;
657 		xdp_ring = vsi->xdp_rings[queue_index];
658 		spin_lock(&xdp_ring->tx_lock);
659 	} else {
660 		/* Generally, should not happen */
661 		if (unlikely(queue_index >= vsi->num_xdp_txq))
662 			return -ENXIO;
663 		xdp_ring = vsi->xdp_rings[queue_index];
664 	}
665 
666 	tx_buf = &xdp_ring->tx_buf[xdp_ring->next_to_use];
667 	for (i = 0; i < n; i++) {
668 		const struct xdp_frame *xdpf = frames[i];
669 		int err;
670 
671 		err = ice_xmit_xdp_ring(xdpf, xdp_ring);
672 		if (err != ICE_XDP_TX)
673 			break;
674 		nxmit++;
675 	}
676 
677 	tx_buf->rs_idx = ice_set_rs_bit(xdp_ring);
678 	if (unlikely(flags & XDP_XMIT_FLUSH))
679 		ice_xdp_ring_update_tail(xdp_ring);
680 
681 	if (static_branch_unlikely(&ice_xdp_locking_key))
682 		spin_unlock(&xdp_ring->tx_lock);
683 
684 	return nxmit;
685 }
686 
687 /**
688  * ice_alloc_mapped_page - recycle or make a new page
689  * @rx_ring: ring to use
690  * @bi: rx_buf struct to modify
691  *
692  * Returns true if the page was successfully allocated or
693  * reused.
694  */
695 static bool
696 ice_alloc_mapped_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *bi)
697 {
698 	struct page *page = bi->page;
699 	dma_addr_t dma;
700 
701 	/* since we are recycling buffers we should seldom need to alloc */
702 	if (likely(page))
703 		return true;
704 
705 	/* alloc new page for storage */
706 	page = dev_alloc_pages(ice_rx_pg_order(rx_ring));
707 	if (unlikely(!page)) {
708 		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
709 		return false;
710 	}
711 
712 	/* map page for use */
713 	dma = dma_map_page_attrs(rx_ring->dev, page, 0, ice_rx_pg_size(rx_ring),
714 				 DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
715 
716 	/* if mapping failed free memory back to system since
717 	 * there isn't much point in holding memory we can't use
718 	 */
719 	if (dma_mapping_error(rx_ring->dev, dma)) {
720 		__free_pages(page, ice_rx_pg_order(rx_ring));
721 		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
722 		return false;
723 	}
724 
725 	bi->dma = dma;
726 	bi->page = page;
727 	bi->page_offset = rx_ring->rx_offset;
728 	page_ref_add(page, USHRT_MAX - 1);
729 	bi->pagecnt_bias = USHRT_MAX;
730 
731 	return true;
732 }
733 
734 /**
735  * ice_alloc_rx_bufs - Replace used receive buffers
736  * @rx_ring: ring to place buffers on
737  * @cleaned_count: number of buffers to replace
738  *
739  * Returns false if all allocations were successful, true if any fail. Returning
740  * true signals to the caller that we didn't replace cleaned_count buffers and
741  * there is more work to do.
742  *
743  * First, try to clean "cleaned_count" Rx buffers. Then refill the cleaned Rx
744  * buffers. Then bump tail at most one time. Grouping like this lets us avoid
745  * multiple tail writes per call.
746  */
747 bool ice_alloc_rx_bufs(struct ice_rx_ring *rx_ring, unsigned int cleaned_count)
748 {
749 	union ice_32b_rx_flex_desc *rx_desc;
750 	u16 ntu = rx_ring->next_to_use;
751 	struct ice_rx_buf *bi;
752 
753 	/* do nothing if no valid netdev defined */
754 	if ((!rx_ring->netdev && rx_ring->vsi->type != ICE_VSI_CTRL) ||
755 	    !cleaned_count)
756 		return false;
757 
758 	/* get the Rx descriptor and buffer based on next_to_use */
759 	rx_desc = ICE_RX_DESC(rx_ring, ntu);
760 	bi = &rx_ring->rx_buf[ntu];
761 
762 	do {
763 		/* if we fail here, we have work remaining */
764 		if (!ice_alloc_mapped_page(rx_ring, bi))
765 			break;
766 
767 		/* sync the buffer for use by the device */
768 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
769 						 bi->page_offset,
770 						 rx_ring->rx_buf_len,
771 						 DMA_FROM_DEVICE);
772 
773 		/* Refresh the desc even if buffer_addrs didn't change
774 		 * because each write-back erases this info.
775 		 */
776 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
777 
778 		rx_desc++;
779 		bi++;
780 		ntu++;
781 		if (unlikely(ntu == rx_ring->count)) {
782 			rx_desc = ICE_RX_DESC(rx_ring, 0);
783 			bi = rx_ring->rx_buf;
784 			ntu = 0;
785 		}
786 
787 		/* clear the status bits for the next_to_use descriptor */
788 		rx_desc->wb.status_error0 = 0;
789 
790 		cleaned_count--;
791 	} while (cleaned_count);
792 
793 	if (rx_ring->next_to_use != ntu)
794 		ice_release_rx_desc(rx_ring, ntu);
795 
796 	return !!cleaned_count;
797 }
798 
799 /**
800  * ice_rx_buf_adjust_pg_offset - Prepare Rx buffer for reuse
801  * @rx_buf: Rx buffer to adjust
802  * @size: Size of adjustment
803  *
804  * Update the offset within page so that Rx buf will be ready to be reused.
805  * For systems with PAGE_SIZE < 8192 this function will flip the page offset
806  * so the second half of page assigned to Rx buffer will be used, otherwise
807  * the offset is moved by "size" bytes
808  */
809 static void
810 ice_rx_buf_adjust_pg_offset(struct ice_rx_buf *rx_buf, unsigned int size)
811 {
812 #if (PAGE_SIZE < 8192)
813 	/* flip page offset to other buffer */
814 	rx_buf->page_offset ^= size;
815 #else
816 	/* move offset up to the next cache line */
817 	rx_buf->page_offset += size;
818 #endif
819 }
820 
821 /**
822  * ice_can_reuse_rx_page - Determine if page can be reused for another Rx
823  * @rx_buf: buffer containing the page
824  *
825  * If page is reusable, we have a green light for calling ice_reuse_rx_page,
826  * which will assign the current buffer to the buffer that next_to_alloc is
827  * pointing to; otherwise, the DMA mapping needs to be destroyed and
828  * page freed
829  */
830 static bool
831 ice_can_reuse_rx_page(struct ice_rx_buf *rx_buf)
832 {
833 	unsigned int pagecnt_bias = rx_buf->pagecnt_bias;
834 	struct page *page = rx_buf->page;
835 
836 	/* avoid re-using remote and pfmemalloc pages */
837 	if (!dev_page_is_reusable(page))
838 		return false;
839 
840 #if (PAGE_SIZE < 8192)
841 	/* if we are only owner of page we can reuse it */
842 	if (unlikely(rx_buf->pgcnt - pagecnt_bias > 1))
843 		return false;
844 #else
845 #define ICE_LAST_OFFSET \
846 	(SKB_WITH_OVERHEAD(PAGE_SIZE) - ICE_RXBUF_2048)
847 	if (rx_buf->page_offset > ICE_LAST_OFFSET)
848 		return false;
849 #endif /* PAGE_SIZE < 8192) */
850 
851 	/* If we have drained the page fragment pool we need to update
852 	 * the pagecnt_bias and page count so that we fully restock the
853 	 * number of references the driver holds.
854 	 */
855 	if (unlikely(pagecnt_bias == 1)) {
856 		page_ref_add(page, USHRT_MAX - 1);
857 		rx_buf->pagecnt_bias = USHRT_MAX;
858 	}
859 
860 	return true;
861 }
862 
863 /**
864  * ice_add_xdp_frag - Add contents of Rx buffer to xdp buf as a frag
865  * @rx_ring: Rx descriptor ring to transact packets on
866  * @xdp: xdp buff to place the data into
867  * @rx_buf: buffer containing page to add
868  * @size: packet length from rx_desc
869  *
870  * This function will add the data contained in rx_buf->page to the xdp buf.
871  * It will just attach the page as a frag.
872  */
873 static int
874 ice_add_xdp_frag(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
875 		 struct ice_rx_buf *rx_buf, const unsigned int size)
876 {
877 	struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp);
878 
879 	if (!size)
880 		return 0;
881 
882 	if (!xdp_buff_has_frags(xdp)) {
883 		sinfo->nr_frags = 0;
884 		sinfo->xdp_frags_size = 0;
885 		xdp_buff_set_frags_flag(xdp);
886 	}
887 
888 	if (unlikely(sinfo->nr_frags == MAX_SKB_FRAGS)) {
889 		ice_set_rx_bufs_act(xdp, rx_ring, ICE_XDP_CONSUMED);
890 		return -ENOMEM;
891 	}
892 
893 	__skb_fill_page_desc_noacc(sinfo, sinfo->nr_frags++, rx_buf->page,
894 				   rx_buf->page_offset, size);
895 	sinfo->xdp_frags_size += size;
896 	/* remember frag count before XDP prog execution; bpf_xdp_adjust_tail()
897 	 * can pop off frags but driver has to handle it on its own
898 	 */
899 	rx_ring->nr_frags = sinfo->nr_frags;
900 
901 	if (page_is_pfmemalloc(rx_buf->page))
902 		xdp_buff_set_frag_pfmemalloc(xdp);
903 
904 	return 0;
905 }
906 
907 /**
908  * ice_reuse_rx_page - page flip buffer and store it back on the ring
909  * @rx_ring: Rx descriptor ring to store buffers on
910  * @old_buf: donor buffer to have page reused
911  *
912  * Synchronizes page for reuse by the adapter
913  */
914 static void
915 ice_reuse_rx_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *old_buf)
916 {
917 	u16 nta = rx_ring->next_to_alloc;
918 	struct ice_rx_buf *new_buf;
919 
920 	new_buf = &rx_ring->rx_buf[nta];
921 
922 	/* update, and store next to alloc */
923 	nta++;
924 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
925 
926 	/* Transfer page from old buffer to new buffer.
927 	 * Move each member individually to avoid possible store
928 	 * forwarding stalls and unnecessary copy of skb.
929 	 */
930 	new_buf->dma = old_buf->dma;
931 	new_buf->page = old_buf->page;
932 	new_buf->page_offset = old_buf->page_offset;
933 	new_buf->pagecnt_bias = old_buf->pagecnt_bias;
934 }
935 
936 /**
937  * ice_get_rx_buf - Fetch Rx buffer and synchronize data for use
938  * @rx_ring: Rx descriptor ring to transact packets on
939  * @size: size of buffer to add to skb
940  * @ntc: index of next to clean element
941  *
942  * This function will pull an Rx buffer from the ring and synchronize it
943  * for use by the CPU.
944  */
945 static struct ice_rx_buf *
946 ice_get_rx_buf(struct ice_rx_ring *rx_ring, const unsigned int size,
947 	       const unsigned int ntc)
948 {
949 	struct ice_rx_buf *rx_buf;
950 
951 	rx_buf = &rx_ring->rx_buf[ntc];
952 	rx_buf->pgcnt =
953 #if (PAGE_SIZE < 8192)
954 		page_count(rx_buf->page);
955 #else
956 		0;
957 #endif
958 	prefetchw(rx_buf->page);
959 
960 	if (!size)
961 		return rx_buf;
962 	/* we are reusing so sync this buffer for CPU use */
963 	dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
964 				      rx_buf->page_offset, size,
965 				      DMA_FROM_DEVICE);
966 
967 	/* We have pulled a buffer for use, so decrement pagecnt_bias */
968 	rx_buf->pagecnt_bias--;
969 
970 	return rx_buf;
971 }
972 
973 /**
974  * ice_build_skb - Build skb around an existing buffer
975  * @rx_ring: Rx descriptor ring to transact packets on
976  * @xdp: xdp_buff pointing to the data
977  *
978  * This function builds an skb around an existing XDP buffer, taking care
979  * to set up the skb correctly and avoid any memcpy overhead. Driver has
980  * already combined frags (if any) to skb_shared_info.
981  */
982 static struct sk_buff *
983 ice_build_skb(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp)
984 {
985 	u8 metasize = xdp->data - xdp->data_meta;
986 	struct skb_shared_info *sinfo = NULL;
987 	unsigned int nr_frags;
988 	struct sk_buff *skb;
989 
990 	if (unlikely(xdp_buff_has_frags(xdp))) {
991 		sinfo = xdp_get_shared_info_from_buff(xdp);
992 		nr_frags = sinfo->nr_frags;
993 	}
994 
995 	/* Prefetch first cache line of first page. If xdp->data_meta
996 	 * is unused, this points exactly as xdp->data, otherwise we
997 	 * likely have a consumer accessing first few bytes of meta
998 	 * data, and then actual data.
999 	 */
1000 	net_prefetch(xdp->data_meta);
1001 	/* build an skb around the page buffer */
1002 	skb = napi_build_skb(xdp->data_hard_start, xdp->frame_sz);
1003 	if (unlikely(!skb))
1004 		return NULL;
1005 
1006 	/* must to record Rx queue, otherwise OS features such as
1007 	 * symmetric queue won't work
1008 	 */
1009 	skb_record_rx_queue(skb, rx_ring->q_index);
1010 
1011 	/* update pointers within the skb to store the data */
1012 	skb_reserve(skb, xdp->data - xdp->data_hard_start);
1013 	__skb_put(skb, xdp->data_end - xdp->data);
1014 	if (metasize)
1015 		skb_metadata_set(skb, metasize);
1016 
1017 	if (unlikely(xdp_buff_has_frags(xdp)))
1018 		xdp_update_skb_shared_info(skb, nr_frags,
1019 					   sinfo->xdp_frags_size,
1020 					   nr_frags * xdp->frame_sz,
1021 					   xdp_buff_is_frag_pfmemalloc(xdp));
1022 
1023 	return skb;
1024 }
1025 
1026 /**
1027  * ice_construct_skb - Allocate skb and populate it
1028  * @rx_ring: Rx descriptor ring to transact packets on
1029  * @xdp: xdp_buff pointing to the data
1030  *
1031  * This function allocates an skb. It then populates it with the page
1032  * data from the current receive descriptor, taking care to set up the
1033  * skb correctly.
1034  */
1035 static struct sk_buff *
1036 ice_construct_skb(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp)
1037 {
1038 	unsigned int size = xdp->data_end - xdp->data;
1039 	struct skb_shared_info *sinfo = NULL;
1040 	struct ice_rx_buf *rx_buf;
1041 	unsigned int nr_frags = 0;
1042 	unsigned int headlen;
1043 	struct sk_buff *skb;
1044 
1045 	/* prefetch first cache line of first page */
1046 	net_prefetch(xdp->data);
1047 
1048 	if (unlikely(xdp_buff_has_frags(xdp))) {
1049 		sinfo = xdp_get_shared_info_from_buff(xdp);
1050 		nr_frags = sinfo->nr_frags;
1051 	}
1052 
1053 	/* allocate a skb to store the frags */
1054 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi, ICE_RX_HDR_SIZE,
1055 			       GFP_ATOMIC | __GFP_NOWARN);
1056 	if (unlikely(!skb))
1057 		return NULL;
1058 
1059 	rx_buf = &rx_ring->rx_buf[rx_ring->first_desc];
1060 	skb_record_rx_queue(skb, rx_ring->q_index);
1061 	/* Determine available headroom for copy */
1062 	headlen = size;
1063 	if (headlen > ICE_RX_HDR_SIZE)
1064 		headlen = eth_get_headlen(skb->dev, xdp->data, ICE_RX_HDR_SIZE);
1065 
1066 	/* align pull length to size of long to optimize memcpy performance */
1067 	memcpy(__skb_put(skb, headlen), xdp->data, ALIGN(headlen,
1068 							 sizeof(long)));
1069 
1070 	/* if we exhaust the linear part then add what is left as a frag */
1071 	size -= headlen;
1072 	if (size) {
1073 		/* besides adding here a partial frag, we are going to add
1074 		 * frags from xdp_buff, make sure there is enough space for
1075 		 * them
1076 		 */
1077 		if (unlikely(nr_frags >= MAX_SKB_FRAGS - 1)) {
1078 			dev_kfree_skb(skb);
1079 			return NULL;
1080 		}
1081 		skb_add_rx_frag(skb, 0, rx_buf->page,
1082 				rx_buf->page_offset + headlen, size,
1083 				xdp->frame_sz);
1084 	} else {
1085 		/* buffer is unused, change the act that should be taken later
1086 		 * on; data was copied onto skb's linear part so there's no
1087 		 * need for adjusting page offset and we can reuse this buffer
1088 		 * as-is
1089 		 */
1090 		rx_buf->act = ICE_SKB_CONSUMED;
1091 	}
1092 
1093 	if (unlikely(xdp_buff_has_frags(xdp))) {
1094 		struct skb_shared_info *skinfo = skb_shinfo(skb);
1095 
1096 		memcpy(&skinfo->frags[skinfo->nr_frags], &sinfo->frags[0],
1097 		       sizeof(skb_frag_t) * nr_frags);
1098 
1099 		xdp_update_skb_shared_info(skb, skinfo->nr_frags + nr_frags,
1100 					   sinfo->xdp_frags_size,
1101 					   nr_frags * xdp->frame_sz,
1102 					   xdp_buff_is_frag_pfmemalloc(xdp));
1103 	}
1104 
1105 	return skb;
1106 }
1107 
1108 /**
1109  * ice_put_rx_buf - Clean up used buffer and either recycle or free
1110  * @rx_ring: Rx descriptor ring to transact packets on
1111  * @rx_buf: Rx buffer to pull data from
1112  *
1113  * This function will clean up the contents of the rx_buf. It will either
1114  * recycle the buffer or unmap it and free the associated resources.
1115  */
1116 static void
1117 ice_put_rx_buf(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf)
1118 {
1119 	if (!rx_buf)
1120 		return;
1121 
1122 	if (ice_can_reuse_rx_page(rx_buf)) {
1123 		/* hand second half of page back to the ring */
1124 		ice_reuse_rx_page(rx_ring, rx_buf);
1125 	} else {
1126 		/* we are not reusing the buffer so unmap it */
1127 		dma_unmap_page_attrs(rx_ring->dev, rx_buf->dma,
1128 				     ice_rx_pg_size(rx_ring), DMA_FROM_DEVICE,
1129 				     ICE_RX_DMA_ATTR);
1130 		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
1131 	}
1132 
1133 	/* clear contents of buffer_info */
1134 	rx_buf->page = NULL;
1135 }
1136 
1137 /**
1138  * ice_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
1139  * @rx_ring: Rx descriptor ring to transact packets on
1140  * @budget: Total limit on number of packets to process
1141  *
1142  * This function provides a "bounce buffer" approach to Rx interrupt
1143  * processing. The advantage to this is that on systems that have
1144  * expensive overhead for IOMMU access this provides a means of avoiding
1145  * it by maintaining the mapping of the page to the system.
1146  *
1147  * Returns amount of work completed
1148  */
1149 int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget)
1150 {
1151 	unsigned int total_rx_bytes = 0, total_rx_pkts = 0;
1152 	unsigned int offset = rx_ring->rx_offset;
1153 	struct xdp_buff *xdp = &rx_ring->xdp;
1154 	u32 cached_ntc = rx_ring->first_desc;
1155 	struct ice_tx_ring *xdp_ring = NULL;
1156 	struct bpf_prog *xdp_prog = NULL;
1157 	u32 ntc = rx_ring->next_to_clean;
1158 	u32 cnt = rx_ring->count;
1159 	u32 xdp_xmit = 0;
1160 	u32 cached_ntu;
1161 	bool failure;
1162 	u32 first;
1163 
1164 	/* Frame size depend on rx_ring setup when PAGE_SIZE=4K */
1165 #if (PAGE_SIZE < 8192)
1166 	xdp->frame_sz = ice_rx_frame_truesize(rx_ring, 0);
1167 #endif
1168 
1169 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
1170 	if (xdp_prog) {
1171 		xdp_ring = rx_ring->xdp_ring;
1172 		cached_ntu = xdp_ring->next_to_use;
1173 	}
1174 
1175 	/* start the loop to process Rx packets bounded by 'budget' */
1176 	while (likely(total_rx_pkts < (unsigned int)budget)) {
1177 		union ice_32b_rx_flex_desc *rx_desc;
1178 		struct ice_rx_buf *rx_buf;
1179 		struct sk_buff *skb;
1180 		unsigned int size;
1181 		u16 stat_err_bits;
1182 		u16 vlan_tci;
1183 
1184 		/* get the Rx desc from Rx ring based on 'next_to_clean' */
1185 		rx_desc = ICE_RX_DESC(rx_ring, ntc);
1186 
1187 		/* status_error_len will always be zero for unused descriptors
1188 		 * because it's cleared in cleanup, and overlaps with hdr_addr
1189 		 * which is always zero because packet split isn't used, if the
1190 		 * hardware wrote DD then it will be non-zero
1191 		 */
1192 		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_DD_S);
1193 		if (!ice_test_staterr(rx_desc->wb.status_error0, stat_err_bits))
1194 			break;
1195 
1196 		/* This memory barrier is needed to keep us from reading
1197 		 * any other fields out of the rx_desc until we know the
1198 		 * DD bit is set.
1199 		 */
1200 		dma_rmb();
1201 
1202 		ice_trace(clean_rx_irq, rx_ring, rx_desc);
1203 		if (rx_desc->wb.rxdid == FDIR_DESC_RXDID || !rx_ring->netdev) {
1204 			struct ice_vsi *ctrl_vsi = rx_ring->vsi;
1205 
1206 			if (rx_desc->wb.rxdid == FDIR_DESC_RXDID &&
1207 			    ctrl_vsi->vf)
1208 				ice_vc_fdir_irq_handler(ctrl_vsi, rx_desc);
1209 			if (++ntc == cnt)
1210 				ntc = 0;
1211 			rx_ring->first_desc = ntc;
1212 			continue;
1213 		}
1214 
1215 		size = le16_to_cpu(rx_desc->wb.pkt_len) &
1216 			ICE_RX_FLX_DESC_PKT_LEN_M;
1217 
1218 		/* retrieve a buffer from the ring */
1219 		rx_buf = ice_get_rx_buf(rx_ring, size, ntc);
1220 
1221 		if (!xdp->data) {
1222 			void *hard_start;
1223 
1224 			hard_start = page_address(rx_buf->page) + rx_buf->page_offset -
1225 				     offset;
1226 			xdp_prepare_buff(xdp, hard_start, offset, size, !!offset);
1227 #if (PAGE_SIZE > 4096)
1228 			/* At larger PAGE_SIZE, frame_sz depend on len size */
1229 			xdp->frame_sz = ice_rx_frame_truesize(rx_ring, size);
1230 #endif
1231 			xdp_buff_clear_frags_flag(xdp);
1232 		} else if (ice_add_xdp_frag(rx_ring, xdp, rx_buf, size)) {
1233 			break;
1234 		}
1235 		if (++ntc == cnt)
1236 			ntc = 0;
1237 
1238 		/* skip if it is NOP desc */
1239 		if (ice_is_non_eop(rx_ring, rx_desc))
1240 			continue;
1241 
1242 		ice_run_xdp(rx_ring, xdp, xdp_prog, xdp_ring, rx_buf, rx_desc);
1243 		if (rx_buf->act == ICE_XDP_PASS)
1244 			goto construct_skb;
1245 		total_rx_bytes += xdp_get_buff_len(xdp);
1246 		total_rx_pkts++;
1247 
1248 		xdp->data = NULL;
1249 		rx_ring->first_desc = ntc;
1250 		rx_ring->nr_frags = 0;
1251 		continue;
1252 construct_skb:
1253 		if (likely(ice_ring_uses_build_skb(rx_ring)))
1254 			skb = ice_build_skb(rx_ring, xdp);
1255 		else
1256 			skb = ice_construct_skb(rx_ring, xdp);
1257 		/* exit if we failed to retrieve a buffer */
1258 		if (!skb) {
1259 			rx_ring->ring_stats->rx_stats.alloc_page_failed++;
1260 			rx_buf->act = ICE_XDP_CONSUMED;
1261 			if (unlikely(xdp_buff_has_frags(xdp)))
1262 				ice_set_rx_bufs_act(xdp, rx_ring,
1263 						    ICE_XDP_CONSUMED);
1264 			xdp->data = NULL;
1265 			rx_ring->first_desc = ntc;
1266 			rx_ring->nr_frags = 0;
1267 			break;
1268 		}
1269 		xdp->data = NULL;
1270 		rx_ring->first_desc = ntc;
1271 		rx_ring->nr_frags = 0;
1272 
1273 		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_RXE_S);
1274 		if (unlikely(ice_test_staterr(rx_desc->wb.status_error0,
1275 					      stat_err_bits))) {
1276 			dev_kfree_skb_any(skb);
1277 			continue;
1278 		}
1279 
1280 		vlan_tci = ice_get_vlan_tci(rx_desc);
1281 
1282 		/* pad the skb if needed, to make a valid ethernet frame */
1283 		if (eth_skb_pad(skb))
1284 			continue;
1285 
1286 		/* probably a little skewed due to removing CRC */
1287 		total_rx_bytes += skb->len;
1288 
1289 		/* populate checksum, VLAN, and protocol */
1290 		ice_process_skb_fields(rx_ring, rx_desc, skb);
1291 
1292 		ice_trace(clean_rx_irq_indicate, rx_ring, rx_desc, skb);
1293 		/* send completed skb up the stack */
1294 		ice_receive_skb(rx_ring, skb, vlan_tci);
1295 
1296 		/* update budget accounting */
1297 		total_rx_pkts++;
1298 	}
1299 
1300 	first = rx_ring->first_desc;
1301 	while (cached_ntc != first) {
1302 		struct ice_rx_buf *buf = &rx_ring->rx_buf[cached_ntc];
1303 
1304 		if (buf->act & (ICE_XDP_TX | ICE_XDP_REDIR)) {
1305 			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);
1306 			xdp_xmit |= buf->act;
1307 		} else if (buf->act & ICE_XDP_CONSUMED) {
1308 			buf->pagecnt_bias++;
1309 		} else if (buf->act == ICE_XDP_PASS) {
1310 			ice_rx_buf_adjust_pg_offset(buf, xdp->frame_sz);
1311 		}
1312 
1313 		ice_put_rx_buf(rx_ring, buf);
1314 		if (++cached_ntc >= cnt)
1315 			cached_ntc = 0;
1316 	}
1317 	rx_ring->next_to_clean = ntc;
1318 	/* return up to cleaned_count buffers to hardware */
1319 	failure = ice_alloc_rx_bufs(rx_ring, ICE_RX_DESC_UNUSED(rx_ring));
1320 
1321 	if (xdp_xmit)
1322 		ice_finalize_xdp_rx(xdp_ring, xdp_xmit, cached_ntu);
1323 
1324 	if (rx_ring->ring_stats)
1325 		ice_update_rx_ring_stats(rx_ring, total_rx_pkts,
1326 					 total_rx_bytes);
1327 
1328 	/* guarantee a trip back through this routine if there was a failure */
1329 	return failure ? budget : (int)total_rx_pkts;
1330 }
1331 
1332 static void __ice_update_sample(struct ice_q_vector *q_vector,
1333 				struct ice_ring_container *rc,
1334 				struct dim_sample *sample,
1335 				bool is_tx)
1336 {
1337 	u64 packets = 0, bytes = 0;
1338 
1339 	if (is_tx) {
1340 		struct ice_tx_ring *tx_ring;
1341 
1342 		ice_for_each_tx_ring(tx_ring, *rc) {
1343 			struct ice_ring_stats *ring_stats;
1344 
1345 			ring_stats = tx_ring->ring_stats;
1346 			if (!ring_stats)
1347 				continue;
1348 			packets += ring_stats->stats.pkts;
1349 			bytes += ring_stats->stats.bytes;
1350 		}
1351 	} else {
1352 		struct ice_rx_ring *rx_ring;
1353 
1354 		ice_for_each_rx_ring(rx_ring, *rc) {
1355 			struct ice_ring_stats *ring_stats;
1356 
1357 			ring_stats = rx_ring->ring_stats;
1358 			if (!ring_stats)
1359 				continue;
1360 			packets += ring_stats->stats.pkts;
1361 			bytes += ring_stats->stats.bytes;
1362 		}
1363 	}
1364 
1365 	dim_update_sample(q_vector->total_events, packets, bytes, sample);
1366 	sample->comp_ctr = 0;
1367 
1368 	/* if dim settings get stale, like when not updated for 1
1369 	 * second or longer, force it to start again. This addresses the
1370 	 * frequent case of an idle queue being switched to by the
1371 	 * scheduler. The 1,000 here means 1,000 milliseconds.
1372 	 */
1373 	if (ktime_ms_delta(sample->time, rc->dim.start_sample.time) >= 1000)
1374 		rc->dim.state = DIM_START_MEASURE;
1375 }
1376 
1377 /**
1378  * ice_net_dim - Update net DIM algorithm
1379  * @q_vector: the vector associated with the interrupt
1380  *
1381  * Create a DIM sample and notify net_dim() so that it can possibly decide
1382  * a new ITR value based on incoming packets, bytes, and interrupts.
1383  *
1384  * This function is a no-op if the ring is not configured to dynamic ITR.
1385  */
1386 static void ice_net_dim(struct ice_q_vector *q_vector)
1387 {
1388 	struct ice_ring_container *tx = &q_vector->tx;
1389 	struct ice_ring_container *rx = &q_vector->rx;
1390 
1391 	if (ITR_IS_DYNAMIC(tx)) {
1392 		struct dim_sample dim_sample;
1393 
1394 		__ice_update_sample(q_vector, tx, &dim_sample, true);
1395 		net_dim(&tx->dim, dim_sample);
1396 	}
1397 
1398 	if (ITR_IS_DYNAMIC(rx)) {
1399 		struct dim_sample dim_sample;
1400 
1401 		__ice_update_sample(q_vector, rx, &dim_sample, false);
1402 		net_dim(&rx->dim, dim_sample);
1403 	}
1404 }
1405 
1406 /**
1407  * ice_buildreg_itr - build value for writing to the GLINT_DYN_CTL register
1408  * @itr_idx: interrupt throttling index
1409  * @itr: interrupt throttling value in usecs
1410  */
1411 static u32 ice_buildreg_itr(u16 itr_idx, u16 itr)
1412 {
1413 	/* The ITR value is reported in microseconds, and the register value is
1414 	 * recorded in 2 microsecond units. For this reason we only need to
1415 	 * shift by the GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S to apply this
1416 	 * granularity as a shift instead of division. The mask makes sure the
1417 	 * ITR value is never odd so we don't accidentally write into the field
1418 	 * prior to the ITR field.
1419 	 */
1420 	itr &= ICE_ITR_MASK;
1421 
1422 	return GLINT_DYN_CTL_INTENA_M | GLINT_DYN_CTL_CLEARPBA_M |
1423 		(itr_idx << GLINT_DYN_CTL_ITR_INDX_S) |
1424 		(itr << (GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S));
1425 }
1426 
1427 /**
1428  * ice_enable_interrupt - re-enable MSI-X interrupt
1429  * @q_vector: the vector associated with the interrupt to enable
1430  *
1431  * If the VSI is down, the interrupt will not be re-enabled. Also,
1432  * when enabling the interrupt always reset the wb_on_itr to false
1433  * and trigger a software interrupt to clean out internal state.
1434  */
1435 static void ice_enable_interrupt(struct ice_q_vector *q_vector)
1436 {
1437 	struct ice_vsi *vsi = q_vector->vsi;
1438 	bool wb_en = q_vector->wb_on_itr;
1439 	u32 itr_val;
1440 
1441 	if (test_bit(ICE_DOWN, vsi->state))
1442 		return;
1443 
1444 	/* trigger an ITR delayed software interrupt when exiting busy poll, to
1445 	 * make sure to catch any pending cleanups that might have been missed
1446 	 * due to interrupt state transition. If busy poll or poll isn't
1447 	 * enabled, then don't update ITR, and just enable the interrupt.
1448 	 */
1449 	if (!wb_en) {
1450 		itr_val = ice_buildreg_itr(ICE_ITR_NONE, 0);
1451 	} else {
1452 		q_vector->wb_on_itr = false;
1453 
1454 		/* do two things here with a single write. Set up the third ITR
1455 		 * index to be used for software interrupt moderation, and then
1456 		 * trigger a software interrupt with a rate limit of 20K on
1457 		 * software interrupts, this will help avoid high interrupt
1458 		 * loads due to frequently polling and exiting polling.
1459 		 */
1460 		itr_val = ice_buildreg_itr(ICE_IDX_ITR2, ICE_ITR_20K);
1461 		itr_val |= GLINT_DYN_CTL_SWINT_TRIG_M |
1462 			   ICE_IDX_ITR2 << GLINT_DYN_CTL_SW_ITR_INDX_S |
1463 			   GLINT_DYN_CTL_SW_ITR_INDX_ENA_M;
1464 	}
1465 	wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
1466 }
1467 
1468 /**
1469  * ice_set_wb_on_itr - set WB_ON_ITR for this q_vector
1470  * @q_vector: q_vector to set WB_ON_ITR on
1471  *
1472  * We need to tell hardware to write-back completed descriptors even when
1473  * interrupts are disabled. Descriptors will be written back on cache line
1474  * boundaries without WB_ON_ITR enabled, but if we don't enable WB_ON_ITR
1475  * descriptors may not be written back if they don't fill a cache line until
1476  * the next interrupt.
1477  *
1478  * This sets the write-back frequency to whatever was set previously for the
1479  * ITR indices. Also, set the INTENA_MSK bit to make sure hardware knows we
1480  * aren't meddling with the INTENA_M bit.
1481  */
1482 static void ice_set_wb_on_itr(struct ice_q_vector *q_vector)
1483 {
1484 	struct ice_vsi *vsi = q_vector->vsi;
1485 
1486 	/* already in wb_on_itr mode no need to change it */
1487 	if (q_vector->wb_on_itr)
1488 		return;
1489 
1490 	/* use previously set ITR values for all of the ITR indices by
1491 	 * specifying ICE_ITR_NONE, which will vary in adaptive (AIM) mode and
1492 	 * be static in non-adaptive mode (user configured)
1493 	 */
1494 	wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1495 	     FIELD_PREP(GLINT_DYN_CTL_ITR_INDX_M, ICE_ITR_NONE) |
1496 	     FIELD_PREP(GLINT_DYN_CTL_INTENA_MSK_M, 1) |
1497 	     FIELD_PREP(GLINT_DYN_CTL_WB_ON_ITR_M, 1));
1498 
1499 	q_vector->wb_on_itr = true;
1500 }
1501 
1502 /**
1503  * ice_napi_poll - NAPI polling Rx/Tx cleanup routine
1504  * @napi: napi struct with our devices info in it
1505  * @budget: amount of work driver is allowed to do this pass, in packets
1506  *
1507  * This function will clean all queues associated with a q_vector.
1508  *
1509  * Returns the amount of work done
1510  */
1511 int ice_napi_poll(struct napi_struct *napi, int budget)
1512 {
1513 	struct ice_q_vector *q_vector =
1514 				container_of(napi, struct ice_q_vector, napi);
1515 	struct ice_tx_ring *tx_ring;
1516 	struct ice_rx_ring *rx_ring;
1517 	bool clean_complete = true;
1518 	int budget_per_ring;
1519 	int work_done = 0;
1520 
1521 	/* Since the actual Tx work is minimal, we can give the Tx a larger
1522 	 * budget and be more aggressive about cleaning up the Tx descriptors.
1523 	 */
1524 	ice_for_each_tx_ring(tx_ring, q_vector->tx) {
1525 		bool wd;
1526 
1527 		if (tx_ring->xsk_pool)
1528 			wd = ice_xmit_zc(tx_ring);
1529 		else if (ice_ring_is_xdp(tx_ring))
1530 			wd = true;
1531 		else
1532 			wd = ice_clean_tx_irq(tx_ring, budget);
1533 
1534 		if (!wd)
1535 			clean_complete = false;
1536 	}
1537 
1538 	/* Handle case where we are called by netpoll with a budget of 0 */
1539 	if (unlikely(budget <= 0))
1540 		return budget;
1541 
1542 	/* normally we have 1 Rx ring per q_vector */
1543 	if (unlikely(q_vector->num_ring_rx > 1))
1544 		/* We attempt to distribute budget to each Rx queue fairly, but
1545 		 * don't allow the budget to go below 1 because that would exit
1546 		 * polling early.
1547 		 */
1548 		budget_per_ring = max_t(int, budget / q_vector->num_ring_rx, 1);
1549 	else
1550 		/* Max of 1 Rx ring in this q_vector so give it the budget */
1551 		budget_per_ring = budget;
1552 
1553 	ice_for_each_rx_ring(rx_ring, q_vector->rx) {
1554 		int cleaned;
1555 
1556 		/* A dedicated path for zero-copy allows making a single
1557 		 * comparison in the irq context instead of many inside the
1558 		 * ice_clean_rx_irq function and makes the codebase cleaner.
1559 		 */
1560 		cleaned = rx_ring->xsk_pool ?
1561 			  ice_clean_rx_irq_zc(rx_ring, budget_per_ring) :
1562 			  ice_clean_rx_irq(rx_ring, budget_per_ring);
1563 		work_done += cleaned;
1564 		/* if we clean as many as budgeted, we must not be done */
1565 		if (cleaned >= budget_per_ring)
1566 			clean_complete = false;
1567 	}
1568 
1569 	/* If work not completed, return budget and polling will return */
1570 	if (!clean_complete) {
1571 		/* Set the writeback on ITR so partial completions of
1572 		 * cache-lines will still continue even if we're polling.
1573 		 */
1574 		ice_set_wb_on_itr(q_vector);
1575 		return budget;
1576 	}
1577 
1578 	/* Exit the polling mode, but don't re-enable interrupts if stack might
1579 	 * poll us due to busy-polling
1580 	 */
1581 	if (napi_complete_done(napi, work_done)) {
1582 		ice_net_dim(q_vector);
1583 		ice_enable_interrupt(q_vector);
1584 	} else {
1585 		ice_set_wb_on_itr(q_vector);
1586 	}
1587 
1588 	return min_t(int, work_done, budget - 1);
1589 }
1590 
1591 /**
1592  * __ice_maybe_stop_tx - 2nd level check for Tx stop conditions
1593  * @tx_ring: the ring to be checked
1594  * @size: the size buffer we want to assure is available
1595  *
1596  * Returns -EBUSY if a stop is needed, else 0
1597  */
1598 static int __ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
1599 {
1600 	netif_tx_stop_queue(txring_txq(tx_ring));
1601 	/* Memory barrier before checking head and tail */
1602 	smp_mb();
1603 
1604 	/* Check again in a case another CPU has just made room available. */
1605 	if (likely(ICE_DESC_UNUSED(tx_ring) < size))
1606 		return -EBUSY;
1607 
1608 	/* A reprieve! - use start_queue because it doesn't call schedule */
1609 	netif_tx_start_queue(txring_txq(tx_ring));
1610 	++tx_ring->ring_stats->tx_stats.restart_q;
1611 	return 0;
1612 }
1613 
1614 /**
1615  * ice_maybe_stop_tx - 1st level check for Tx stop conditions
1616  * @tx_ring: the ring to be checked
1617  * @size:    the size buffer we want to assure is available
1618  *
1619  * Returns 0 if stop is not needed
1620  */
1621 static int ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
1622 {
1623 	if (likely(ICE_DESC_UNUSED(tx_ring) >= size))
1624 		return 0;
1625 
1626 	return __ice_maybe_stop_tx(tx_ring, size);
1627 }
1628 
1629 /**
1630  * ice_tx_map - Build the Tx descriptor
1631  * @tx_ring: ring to send buffer on
1632  * @first: first buffer info buffer to use
1633  * @off: pointer to struct that holds offload parameters
1634  *
1635  * This function loops over the skb data pointed to by *first
1636  * and gets a physical address for each memory location and programs
1637  * it and the length into the transmit descriptor.
1638  */
1639 static void
1640 ice_tx_map(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first,
1641 	   struct ice_tx_offload_params *off)
1642 {
1643 	u64 td_offset, td_tag, td_cmd;
1644 	u16 i = tx_ring->next_to_use;
1645 	unsigned int data_len, size;
1646 	struct ice_tx_desc *tx_desc;
1647 	struct ice_tx_buf *tx_buf;
1648 	struct sk_buff *skb;
1649 	skb_frag_t *frag;
1650 	dma_addr_t dma;
1651 	bool kick;
1652 
1653 	td_tag = off->td_l2tag1;
1654 	td_cmd = off->td_cmd;
1655 	td_offset = off->td_offset;
1656 	skb = first->skb;
1657 
1658 	data_len = skb->data_len;
1659 	size = skb_headlen(skb);
1660 
1661 	tx_desc = ICE_TX_DESC(tx_ring, i);
1662 
1663 	if (first->tx_flags & ICE_TX_FLAGS_HW_VLAN) {
1664 		td_cmd |= (u64)ICE_TX_DESC_CMD_IL2TAG1;
1665 		td_tag = first->vid;
1666 	}
1667 
1668 	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1669 
1670 	tx_buf = first;
1671 
1672 	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1673 		unsigned int max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1674 
1675 		if (dma_mapping_error(tx_ring->dev, dma))
1676 			goto dma_error;
1677 
1678 		/* record length, and DMA address */
1679 		dma_unmap_len_set(tx_buf, len, size);
1680 		dma_unmap_addr_set(tx_buf, dma, dma);
1681 
1682 		/* align size to end of page */
1683 		max_data += -dma & (ICE_MAX_READ_REQ_SIZE - 1);
1684 		tx_desc->buf_addr = cpu_to_le64(dma);
1685 
1686 		/* account for data chunks larger than the hardware
1687 		 * can handle
1688 		 */
1689 		while (unlikely(size > ICE_MAX_DATA_PER_TXD)) {
1690 			tx_desc->cmd_type_offset_bsz =
1691 				ice_build_ctob(td_cmd, td_offset, max_data,
1692 					       td_tag);
1693 
1694 			tx_desc++;
1695 			i++;
1696 
1697 			if (i == tx_ring->count) {
1698 				tx_desc = ICE_TX_DESC(tx_ring, 0);
1699 				i = 0;
1700 			}
1701 
1702 			dma += max_data;
1703 			size -= max_data;
1704 
1705 			max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1706 			tx_desc->buf_addr = cpu_to_le64(dma);
1707 		}
1708 
1709 		if (likely(!data_len))
1710 			break;
1711 
1712 		tx_desc->cmd_type_offset_bsz = ice_build_ctob(td_cmd, td_offset,
1713 							      size, td_tag);
1714 
1715 		tx_desc++;
1716 		i++;
1717 
1718 		if (i == tx_ring->count) {
1719 			tx_desc = ICE_TX_DESC(tx_ring, 0);
1720 			i = 0;
1721 		}
1722 
1723 		size = skb_frag_size(frag);
1724 		data_len -= size;
1725 
1726 		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1727 				       DMA_TO_DEVICE);
1728 
1729 		tx_buf = &tx_ring->tx_buf[i];
1730 		tx_buf->type = ICE_TX_BUF_FRAG;
1731 	}
1732 
1733 	/* record SW timestamp if HW timestamp is not available */
1734 	skb_tx_timestamp(first->skb);
1735 
1736 	i++;
1737 	if (i == tx_ring->count)
1738 		i = 0;
1739 
1740 	/* write last descriptor with RS and EOP bits */
1741 	td_cmd |= (u64)ICE_TXD_LAST_DESC_CMD;
1742 	tx_desc->cmd_type_offset_bsz =
1743 			ice_build_ctob(td_cmd, td_offset, size, td_tag);
1744 
1745 	/* Force memory writes to complete before letting h/w know there
1746 	 * are new descriptors to fetch.
1747 	 *
1748 	 * We also use this memory barrier to make certain all of the
1749 	 * status bits have been updated before next_to_watch is written.
1750 	 */
1751 	wmb();
1752 
1753 	/* set next_to_watch value indicating a packet is present */
1754 	first->next_to_watch = tx_desc;
1755 
1756 	tx_ring->next_to_use = i;
1757 
1758 	ice_maybe_stop_tx(tx_ring, DESC_NEEDED);
1759 
1760 	/* notify HW of packet */
1761 	kick = __netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount,
1762 				      netdev_xmit_more());
1763 	if (kick)
1764 		/* notify HW of packet */
1765 		writel(i, tx_ring->tail);
1766 
1767 	return;
1768 
1769 dma_error:
1770 	/* clear DMA mappings for failed tx_buf map */
1771 	for (;;) {
1772 		tx_buf = &tx_ring->tx_buf[i];
1773 		ice_unmap_and_free_tx_buf(tx_ring, tx_buf);
1774 		if (tx_buf == first)
1775 			break;
1776 		if (i == 0)
1777 			i = tx_ring->count;
1778 		i--;
1779 	}
1780 
1781 	tx_ring->next_to_use = i;
1782 }
1783 
1784 /**
1785  * ice_tx_csum - Enable Tx checksum offloads
1786  * @first: pointer to the first descriptor
1787  * @off: pointer to struct that holds offload parameters
1788  *
1789  * Returns 0 or error (negative) if checksum offload can't happen, 1 otherwise.
1790  */
1791 static
1792 int ice_tx_csum(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
1793 {
1794 	u32 l4_len = 0, l3_len = 0, l2_len = 0;
1795 	struct sk_buff *skb = first->skb;
1796 	union {
1797 		struct iphdr *v4;
1798 		struct ipv6hdr *v6;
1799 		unsigned char *hdr;
1800 	} ip;
1801 	union {
1802 		struct tcphdr *tcp;
1803 		unsigned char *hdr;
1804 	} l4;
1805 	__be16 frag_off, protocol;
1806 	unsigned char *exthdr;
1807 	u32 offset, cmd = 0;
1808 	u8 l4_proto = 0;
1809 
1810 	if (skb->ip_summed != CHECKSUM_PARTIAL)
1811 		return 0;
1812 
1813 	protocol = vlan_get_protocol(skb);
1814 
1815 	if (eth_p_mpls(protocol)) {
1816 		ip.hdr = skb_inner_network_header(skb);
1817 		l4.hdr = skb_checksum_start(skb);
1818 	} else {
1819 		ip.hdr = skb_network_header(skb);
1820 		l4.hdr = skb_transport_header(skb);
1821 	}
1822 
1823 	/* compute outer L2 header size */
1824 	l2_len = ip.hdr - skb->data;
1825 	offset = (l2_len / 2) << ICE_TX_DESC_LEN_MACLEN_S;
1826 
1827 	/* set the tx_flags to indicate the IP protocol type. this is
1828 	 * required so that checksum header computation below is accurate.
1829 	 */
1830 	if (ip.v4->version == 4)
1831 		first->tx_flags |= ICE_TX_FLAGS_IPV4;
1832 	else if (ip.v6->version == 6)
1833 		first->tx_flags |= ICE_TX_FLAGS_IPV6;
1834 
1835 	if (skb->encapsulation) {
1836 		bool gso_ena = false;
1837 		u32 tunnel = 0;
1838 
1839 		/* define outer network header type */
1840 		if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1841 			tunnel |= (first->tx_flags & ICE_TX_FLAGS_TSO) ?
1842 				  ICE_TX_CTX_EIPT_IPV4 :
1843 				  ICE_TX_CTX_EIPT_IPV4_NO_CSUM;
1844 			l4_proto = ip.v4->protocol;
1845 		} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
1846 			int ret;
1847 
1848 			tunnel |= ICE_TX_CTX_EIPT_IPV6;
1849 			exthdr = ip.hdr + sizeof(*ip.v6);
1850 			l4_proto = ip.v6->nexthdr;
1851 			ret = ipv6_skip_exthdr(skb, exthdr - skb->data,
1852 					       &l4_proto, &frag_off);
1853 			if (ret < 0)
1854 				return -1;
1855 		}
1856 
1857 		/* define outer transport */
1858 		switch (l4_proto) {
1859 		case IPPROTO_UDP:
1860 			tunnel |= ICE_TXD_CTX_UDP_TUNNELING;
1861 			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1862 			break;
1863 		case IPPROTO_GRE:
1864 			tunnel |= ICE_TXD_CTX_GRE_TUNNELING;
1865 			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1866 			break;
1867 		case IPPROTO_IPIP:
1868 		case IPPROTO_IPV6:
1869 			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1870 			l4.hdr = skb_inner_network_header(skb);
1871 			break;
1872 		default:
1873 			if (first->tx_flags & ICE_TX_FLAGS_TSO)
1874 				return -1;
1875 
1876 			skb_checksum_help(skb);
1877 			return 0;
1878 		}
1879 
1880 		/* compute outer L3 header size */
1881 		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
1882 			  ICE_TXD_CTX_QW0_EIPLEN_S;
1883 
1884 		/* switch IP header pointer from outer to inner header */
1885 		ip.hdr = skb_inner_network_header(skb);
1886 
1887 		/* compute tunnel header size */
1888 		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
1889 			   ICE_TXD_CTX_QW0_NATLEN_S;
1890 
1891 		gso_ena = skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL;
1892 		/* indicate if we need to offload outer UDP header */
1893 		if ((first->tx_flags & ICE_TX_FLAGS_TSO) && !gso_ena &&
1894 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
1895 			tunnel |= ICE_TXD_CTX_QW0_L4T_CS_M;
1896 
1897 		/* record tunnel offload values */
1898 		off->cd_tunnel_params |= tunnel;
1899 
1900 		/* set DTYP=1 to indicate that it's an Tx context descriptor
1901 		 * in IPsec tunnel mode with Tx offloads in Quad word 1
1902 		 */
1903 		off->cd_qw1 |= (u64)ICE_TX_DESC_DTYPE_CTX;
1904 
1905 		/* switch L4 header pointer from outer to inner */
1906 		l4.hdr = skb_inner_transport_header(skb);
1907 		l4_proto = 0;
1908 
1909 		/* reset type as we transition from outer to inner headers */
1910 		first->tx_flags &= ~(ICE_TX_FLAGS_IPV4 | ICE_TX_FLAGS_IPV6);
1911 		if (ip.v4->version == 4)
1912 			first->tx_flags |= ICE_TX_FLAGS_IPV4;
1913 		if (ip.v6->version == 6)
1914 			first->tx_flags |= ICE_TX_FLAGS_IPV6;
1915 	}
1916 
1917 	/* Enable IP checksum offloads */
1918 	if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1919 		l4_proto = ip.v4->protocol;
1920 		/* the stack computes the IP header already, the only time we
1921 		 * need the hardware to recompute it is in the case of TSO.
1922 		 */
1923 		if (first->tx_flags & ICE_TX_FLAGS_TSO)
1924 			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4_CSUM;
1925 		else
1926 			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4;
1927 
1928 	} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
1929 		cmd |= ICE_TX_DESC_CMD_IIPT_IPV6;
1930 		exthdr = ip.hdr + sizeof(*ip.v6);
1931 		l4_proto = ip.v6->nexthdr;
1932 		if (l4.hdr != exthdr)
1933 			ipv6_skip_exthdr(skb, exthdr - skb->data, &l4_proto,
1934 					 &frag_off);
1935 	} else {
1936 		return -1;
1937 	}
1938 
1939 	/* compute inner L3 header size */
1940 	l3_len = l4.hdr - ip.hdr;
1941 	offset |= (l3_len / 4) << ICE_TX_DESC_LEN_IPLEN_S;
1942 
1943 	/* Enable L4 checksum offloads */
1944 	switch (l4_proto) {
1945 	case IPPROTO_TCP:
1946 		/* enable checksum offloads */
1947 		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_TCP;
1948 		l4_len = l4.tcp->doff;
1949 		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
1950 		break;
1951 	case IPPROTO_UDP:
1952 		/* enable UDP checksum offload */
1953 		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_UDP;
1954 		l4_len = (sizeof(struct udphdr) >> 2);
1955 		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
1956 		break;
1957 	case IPPROTO_SCTP:
1958 		/* enable SCTP checksum offload */
1959 		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_SCTP;
1960 		l4_len = sizeof(struct sctphdr) >> 2;
1961 		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
1962 		break;
1963 
1964 	default:
1965 		if (first->tx_flags & ICE_TX_FLAGS_TSO)
1966 			return -1;
1967 		skb_checksum_help(skb);
1968 		return 0;
1969 	}
1970 
1971 	off->td_cmd |= cmd;
1972 	off->td_offset |= offset;
1973 	return 1;
1974 }
1975 
1976 /**
1977  * ice_tx_prepare_vlan_flags - prepare generic Tx VLAN tagging flags for HW
1978  * @tx_ring: ring to send buffer on
1979  * @first: pointer to struct ice_tx_buf
1980  *
1981  * Checks the skb and set up correspondingly several generic transmit flags
1982  * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
1983  */
1984 static void
1985 ice_tx_prepare_vlan_flags(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first)
1986 {
1987 	struct sk_buff *skb = first->skb;
1988 
1989 	/* nothing left to do, software offloaded VLAN */
1990 	if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol))
1991 		return;
1992 
1993 	/* the VLAN ethertype/tpid is determined by VSI configuration and netdev
1994 	 * feature flags, which the driver only allows either 802.1Q or 802.1ad
1995 	 * VLAN offloads exclusively so we only care about the VLAN ID here
1996 	 */
1997 	if (skb_vlan_tag_present(skb)) {
1998 		first->vid = skb_vlan_tag_get(skb);
1999 		if (tx_ring->flags & ICE_TX_FLAGS_RING_VLAN_L2TAG2)
2000 			first->tx_flags |= ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN;
2001 		else
2002 			first->tx_flags |= ICE_TX_FLAGS_HW_VLAN;
2003 	}
2004 
2005 	ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
2006 }
2007 
2008 /**
2009  * ice_tso - computes mss and TSO length to prepare for TSO
2010  * @first: pointer to struct ice_tx_buf
2011  * @off: pointer to struct that holds offload parameters
2012  *
2013  * Returns 0 or error (negative) if TSO can't happen, 1 otherwise.
2014  */
2015 static
2016 int ice_tso(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2017 {
2018 	struct sk_buff *skb = first->skb;
2019 	union {
2020 		struct iphdr *v4;
2021 		struct ipv6hdr *v6;
2022 		unsigned char *hdr;
2023 	} ip;
2024 	union {
2025 		struct tcphdr *tcp;
2026 		struct udphdr *udp;
2027 		unsigned char *hdr;
2028 	} l4;
2029 	u64 cd_mss, cd_tso_len;
2030 	__be16 protocol;
2031 	u32 paylen;
2032 	u8 l4_start;
2033 	int err;
2034 
2035 	if (skb->ip_summed != CHECKSUM_PARTIAL)
2036 		return 0;
2037 
2038 	if (!skb_is_gso(skb))
2039 		return 0;
2040 
2041 	err = skb_cow_head(skb, 0);
2042 	if (err < 0)
2043 		return err;
2044 
2045 	protocol = vlan_get_protocol(skb);
2046 
2047 	if (eth_p_mpls(protocol))
2048 		ip.hdr = skb_inner_network_header(skb);
2049 	else
2050 		ip.hdr = skb_network_header(skb);
2051 	l4.hdr = skb_checksum_start(skb);
2052 
2053 	/* initialize outer IP header fields */
2054 	if (ip.v4->version == 4) {
2055 		ip.v4->tot_len = 0;
2056 		ip.v4->check = 0;
2057 	} else {
2058 		ip.v6->payload_len = 0;
2059 	}
2060 
2061 	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2062 					 SKB_GSO_GRE_CSUM |
2063 					 SKB_GSO_IPXIP4 |
2064 					 SKB_GSO_IPXIP6 |
2065 					 SKB_GSO_UDP_TUNNEL |
2066 					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2067 		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2068 		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2069 			l4.udp->len = 0;
2070 
2071 			/* determine offset of outer transport header */
2072 			l4_start = (u8)(l4.hdr - skb->data);
2073 
2074 			/* remove payload length from outer checksum */
2075 			paylen = skb->len - l4_start;
2076 			csum_replace_by_diff(&l4.udp->check,
2077 					     (__force __wsum)htonl(paylen));
2078 		}
2079 
2080 		/* reset pointers to inner headers */
2081 		ip.hdr = skb_inner_network_header(skb);
2082 		l4.hdr = skb_inner_transport_header(skb);
2083 
2084 		/* initialize inner IP header fields */
2085 		if (ip.v4->version == 4) {
2086 			ip.v4->tot_len = 0;
2087 			ip.v4->check = 0;
2088 		} else {
2089 			ip.v6->payload_len = 0;
2090 		}
2091 	}
2092 
2093 	/* determine offset of transport header */
2094 	l4_start = (u8)(l4.hdr - skb->data);
2095 
2096 	/* remove payload length from checksum */
2097 	paylen = skb->len - l4_start;
2098 
2099 	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
2100 		csum_replace_by_diff(&l4.udp->check,
2101 				     (__force __wsum)htonl(paylen));
2102 		/* compute length of UDP segmentation header */
2103 		off->header_len = (u8)sizeof(l4.udp) + l4_start;
2104 	} else {
2105 		csum_replace_by_diff(&l4.tcp->check,
2106 				     (__force __wsum)htonl(paylen));
2107 		/* compute length of TCP segmentation header */
2108 		off->header_len = (u8)((l4.tcp->doff * 4) + l4_start);
2109 	}
2110 
2111 	/* update gso_segs and bytecount */
2112 	first->gso_segs = skb_shinfo(skb)->gso_segs;
2113 	first->bytecount += (first->gso_segs - 1) * off->header_len;
2114 
2115 	cd_tso_len = skb->len - off->header_len;
2116 	cd_mss = skb_shinfo(skb)->gso_size;
2117 
2118 	/* record cdesc_qw1 with TSO parameters */
2119 	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2120 			     (ICE_TX_CTX_DESC_TSO << ICE_TXD_CTX_QW1_CMD_S) |
2121 			     (cd_tso_len << ICE_TXD_CTX_QW1_TSO_LEN_S) |
2122 			     (cd_mss << ICE_TXD_CTX_QW1_MSS_S));
2123 	first->tx_flags |= ICE_TX_FLAGS_TSO;
2124 	return 1;
2125 }
2126 
2127 /**
2128  * ice_txd_use_count  - estimate the number of descriptors needed for Tx
2129  * @size: transmit request size in bytes
2130  *
2131  * Due to hardware alignment restrictions (4K alignment), we need to
2132  * assume that we can have no more than 12K of data per descriptor, even
2133  * though each descriptor can take up to 16K - 1 bytes of aligned memory.
2134  * Thus, we need to divide by 12K. But division is slow! Instead,
2135  * we decompose the operation into shifts and one relatively cheap
2136  * multiply operation.
2137  *
2138  * To divide by 12K, we first divide by 4K, then divide by 3:
2139  *     To divide by 4K, shift right by 12 bits
2140  *     To divide by 3, multiply by 85, then divide by 256
2141  *     (Divide by 256 is done by shifting right by 8 bits)
2142  * Finally, we add one to round up. Because 256 isn't an exact multiple of
2143  * 3, we'll underestimate near each multiple of 12K. This is actually more
2144  * accurate as we have 4K - 1 of wiggle room that we can fit into the last
2145  * segment. For our purposes this is accurate out to 1M which is orders of
2146  * magnitude greater than our largest possible GSO size.
2147  *
2148  * This would then be implemented as:
2149  *     return (((size >> 12) * 85) >> 8) + ICE_DESCS_FOR_SKB_DATA_PTR;
2150  *
2151  * Since multiplication and division are commutative, we can reorder
2152  * operations into:
2153  *     return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2154  */
2155 static unsigned int ice_txd_use_count(unsigned int size)
2156 {
2157 	return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2158 }
2159 
2160 /**
2161  * ice_xmit_desc_count - calculate number of Tx descriptors needed
2162  * @skb: send buffer
2163  *
2164  * Returns number of data descriptors needed for this skb.
2165  */
2166 static unsigned int ice_xmit_desc_count(struct sk_buff *skb)
2167 {
2168 	const skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
2169 	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
2170 	unsigned int count = 0, size = skb_headlen(skb);
2171 
2172 	for (;;) {
2173 		count += ice_txd_use_count(size);
2174 
2175 		if (!nr_frags--)
2176 			break;
2177 
2178 		size = skb_frag_size(frag++);
2179 	}
2180 
2181 	return count;
2182 }
2183 
2184 /**
2185  * __ice_chk_linearize - Check if there are more than 8 buffers per packet
2186  * @skb: send buffer
2187  *
2188  * Note: This HW can't DMA more than 8 buffers to build a packet on the wire
2189  * and so we need to figure out the cases where we need to linearize the skb.
2190  *
2191  * For TSO we need to count the TSO header and segment payload separately.
2192  * As such we need to check cases where we have 7 fragments or more as we
2193  * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2194  * the segment payload in the first descriptor, and another 7 for the
2195  * fragments.
2196  */
2197 static bool __ice_chk_linearize(struct sk_buff *skb)
2198 {
2199 	const skb_frag_t *frag, *stale;
2200 	int nr_frags, sum;
2201 
2202 	/* no need to check if number of frags is less than 7 */
2203 	nr_frags = skb_shinfo(skb)->nr_frags;
2204 	if (nr_frags < (ICE_MAX_BUF_TXD - 1))
2205 		return false;
2206 
2207 	/* We need to walk through the list and validate that each group
2208 	 * of 6 fragments totals at least gso_size.
2209 	 */
2210 	nr_frags -= ICE_MAX_BUF_TXD - 2;
2211 	frag = &skb_shinfo(skb)->frags[0];
2212 
2213 	/* Initialize size to the negative value of gso_size minus 1. We
2214 	 * use this as the worst case scenario in which the frag ahead
2215 	 * of us only provides one byte which is why we are limited to 6
2216 	 * descriptors for a single transmit as the header and previous
2217 	 * fragment are already consuming 2 descriptors.
2218 	 */
2219 	sum = 1 - skb_shinfo(skb)->gso_size;
2220 
2221 	/* Add size of frags 0 through 4 to create our initial sum */
2222 	sum += skb_frag_size(frag++);
2223 	sum += skb_frag_size(frag++);
2224 	sum += skb_frag_size(frag++);
2225 	sum += skb_frag_size(frag++);
2226 	sum += skb_frag_size(frag++);
2227 
2228 	/* Walk through fragments adding latest fragment, testing it, and
2229 	 * then removing stale fragments from the sum.
2230 	 */
2231 	for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
2232 		int stale_size = skb_frag_size(stale);
2233 
2234 		sum += skb_frag_size(frag++);
2235 
2236 		/* The stale fragment may present us with a smaller
2237 		 * descriptor than the actual fragment size. To account
2238 		 * for that we need to remove all the data on the front and
2239 		 * figure out what the remainder would be in the last
2240 		 * descriptor associated with the fragment.
2241 		 */
2242 		if (stale_size > ICE_MAX_DATA_PER_TXD) {
2243 			int align_pad = -(skb_frag_off(stale)) &
2244 					(ICE_MAX_READ_REQ_SIZE - 1);
2245 
2246 			sum -= align_pad;
2247 			stale_size -= align_pad;
2248 
2249 			do {
2250 				sum -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2251 				stale_size -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2252 			} while (stale_size > ICE_MAX_DATA_PER_TXD);
2253 		}
2254 
2255 		/* if sum is negative we failed to make sufficient progress */
2256 		if (sum < 0)
2257 			return true;
2258 
2259 		if (!nr_frags--)
2260 			break;
2261 
2262 		sum -= stale_size;
2263 	}
2264 
2265 	return false;
2266 }
2267 
2268 /**
2269  * ice_chk_linearize - Check if there are more than 8 fragments per packet
2270  * @skb:      send buffer
2271  * @count:    number of buffers used
2272  *
2273  * Note: Our HW can't scatter-gather more than 8 fragments to build
2274  * a packet on the wire and so we need to figure out the cases where we
2275  * need to linearize the skb.
2276  */
2277 static bool ice_chk_linearize(struct sk_buff *skb, unsigned int count)
2278 {
2279 	/* Both TSO and single send will work if count is less than 8 */
2280 	if (likely(count < ICE_MAX_BUF_TXD))
2281 		return false;
2282 
2283 	if (skb_is_gso(skb))
2284 		return __ice_chk_linearize(skb);
2285 
2286 	/* we can support up to 8 data buffers for a single send */
2287 	return count != ICE_MAX_BUF_TXD;
2288 }
2289 
2290 /**
2291  * ice_tstamp - set up context descriptor for hardware timestamp
2292  * @tx_ring: pointer to the Tx ring to send buffer on
2293  * @skb: pointer to the SKB we're sending
2294  * @first: Tx buffer
2295  * @off: Tx offload parameters
2296  */
2297 static void
2298 ice_tstamp(struct ice_tx_ring *tx_ring, struct sk_buff *skb,
2299 	   struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2300 {
2301 	s8 idx;
2302 
2303 	/* only timestamp the outbound packet if the user has requested it */
2304 	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2305 		return;
2306 
2307 	/* Tx timestamps cannot be sampled when doing TSO */
2308 	if (first->tx_flags & ICE_TX_FLAGS_TSO)
2309 		return;
2310 
2311 	/* Grab an open timestamp slot */
2312 	idx = ice_ptp_request_ts(tx_ring->tx_tstamps, skb);
2313 	if (idx < 0) {
2314 		tx_ring->vsi->back->ptp.tx_hwtstamp_skipped++;
2315 		return;
2316 	}
2317 
2318 	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2319 			     (ICE_TX_CTX_DESC_TSYN << ICE_TXD_CTX_QW1_CMD_S) |
2320 			     ((u64)idx << ICE_TXD_CTX_QW1_TSO_LEN_S));
2321 	first->tx_flags |= ICE_TX_FLAGS_TSYN;
2322 }
2323 
2324 /**
2325  * ice_xmit_frame_ring - Sends buffer on Tx ring
2326  * @skb: send buffer
2327  * @tx_ring: ring to send buffer on
2328  *
2329  * Returns NETDEV_TX_OK if sent, else an error code
2330  */
2331 static netdev_tx_t
2332 ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
2333 {
2334 	struct ice_tx_offload_params offload = { 0 };
2335 	struct ice_vsi *vsi = tx_ring->vsi;
2336 	struct ice_tx_buf *first;
2337 	struct ethhdr *eth;
2338 	unsigned int count;
2339 	int tso, csum;
2340 
2341 	ice_trace(xmit_frame_ring, tx_ring, skb);
2342 
2343 	if (unlikely(ipv6_hopopt_jumbo_remove(skb)))
2344 		goto out_drop;
2345 
2346 	count = ice_xmit_desc_count(skb);
2347 	if (ice_chk_linearize(skb, count)) {
2348 		if (__skb_linearize(skb))
2349 			goto out_drop;
2350 		count = ice_txd_use_count(skb->len);
2351 		tx_ring->ring_stats->tx_stats.tx_linearize++;
2352 	}
2353 
2354 	/* need: 1 descriptor per page * PAGE_SIZE/ICE_MAX_DATA_PER_TXD,
2355 	 *       + 1 desc for skb_head_len/ICE_MAX_DATA_PER_TXD,
2356 	 *       + 4 desc gap to avoid the cache line where head is,
2357 	 *       + 1 desc for context descriptor,
2358 	 * otherwise try next time
2359 	 */
2360 	if (ice_maybe_stop_tx(tx_ring, count + ICE_DESCS_PER_CACHE_LINE +
2361 			      ICE_DESCS_FOR_CTX_DESC)) {
2362 		tx_ring->ring_stats->tx_stats.tx_busy++;
2363 		return NETDEV_TX_BUSY;
2364 	}
2365 
2366 	/* prefetch for bql data which is infrequently used */
2367 	netdev_txq_bql_enqueue_prefetchw(txring_txq(tx_ring));
2368 
2369 	offload.tx_ring = tx_ring;
2370 
2371 	/* record the location of the first descriptor for this packet */
2372 	first = &tx_ring->tx_buf[tx_ring->next_to_use];
2373 	first->skb = skb;
2374 	first->type = ICE_TX_BUF_SKB;
2375 	first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
2376 	first->gso_segs = 1;
2377 	first->tx_flags = 0;
2378 
2379 	/* prepare the VLAN tagging flags for Tx */
2380 	ice_tx_prepare_vlan_flags(tx_ring, first);
2381 	if (first->tx_flags & ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN) {
2382 		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2383 					(ICE_TX_CTX_DESC_IL2TAG2 <<
2384 					ICE_TXD_CTX_QW1_CMD_S));
2385 		offload.cd_l2tag2 = first->vid;
2386 	}
2387 
2388 	/* set up TSO offload */
2389 	tso = ice_tso(first, &offload);
2390 	if (tso < 0)
2391 		goto out_drop;
2392 
2393 	/* always set up Tx checksum offload */
2394 	csum = ice_tx_csum(first, &offload);
2395 	if (csum < 0)
2396 		goto out_drop;
2397 
2398 	/* allow CONTROL frames egress from main VSI if FW LLDP disabled */
2399 	eth = (struct ethhdr *)skb_mac_header(skb);
2400 	if (unlikely((skb->priority == TC_PRIO_CONTROL ||
2401 		      eth->h_proto == htons(ETH_P_LLDP)) &&
2402 		     vsi->type == ICE_VSI_PF &&
2403 		     vsi->port_info->qos_cfg.is_sw_lldp))
2404 		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2405 					ICE_TX_CTX_DESC_SWTCH_UPLINK <<
2406 					ICE_TXD_CTX_QW1_CMD_S);
2407 
2408 	ice_tstamp(tx_ring, skb, first, &offload);
2409 	if (ice_is_switchdev_running(vsi->back))
2410 		ice_eswitch_set_target_vsi(skb, &offload);
2411 
2412 	if (offload.cd_qw1 & ICE_TX_DESC_DTYPE_CTX) {
2413 		struct ice_tx_ctx_desc *cdesc;
2414 		u16 i = tx_ring->next_to_use;
2415 
2416 		/* grab the next descriptor */
2417 		cdesc = ICE_TX_CTX_DESC(tx_ring, i);
2418 		i++;
2419 		tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2420 
2421 		/* setup context descriptor */
2422 		cdesc->tunneling_params = cpu_to_le32(offload.cd_tunnel_params);
2423 		cdesc->l2tag2 = cpu_to_le16(offload.cd_l2tag2);
2424 		cdesc->rsvd = cpu_to_le16(0);
2425 		cdesc->qw1 = cpu_to_le64(offload.cd_qw1);
2426 	}
2427 
2428 	ice_tx_map(tx_ring, first, &offload);
2429 	return NETDEV_TX_OK;
2430 
2431 out_drop:
2432 	ice_trace(xmit_frame_ring_drop, tx_ring, skb);
2433 	dev_kfree_skb_any(skb);
2434 	return NETDEV_TX_OK;
2435 }
2436 
2437 /**
2438  * ice_start_xmit - Selects the correct VSI and Tx queue to send buffer
2439  * @skb: send buffer
2440  * @netdev: network interface device structure
2441  *
2442  * Returns NETDEV_TX_OK if sent, else an error code
2443  */
2444 netdev_tx_t ice_start_xmit(struct sk_buff *skb, struct net_device *netdev)
2445 {
2446 	struct ice_netdev_priv *np = netdev_priv(netdev);
2447 	struct ice_vsi *vsi = np->vsi;
2448 	struct ice_tx_ring *tx_ring;
2449 
2450 	tx_ring = vsi->tx_rings[skb->queue_mapping];
2451 
2452 	/* hardware can't handle really short frames, hardware padding works
2453 	 * beyond this point
2454 	 */
2455 	if (skb_put_padto(skb, ICE_MIN_TX_LEN))
2456 		return NETDEV_TX_OK;
2457 
2458 	return ice_xmit_frame_ring(skb, tx_ring);
2459 }
2460 
2461 /**
2462  * ice_get_dscp_up - return the UP/TC value for a SKB
2463  * @dcbcfg: DCB config that contains DSCP to UP/TC mapping
2464  * @skb: SKB to query for info to determine UP/TC
2465  *
2466  * This function is to only be called when the PF is in L3 DSCP PFC mode
2467  */
2468 static u8 ice_get_dscp_up(struct ice_dcbx_cfg *dcbcfg, struct sk_buff *skb)
2469 {
2470 	u8 dscp = 0;
2471 
2472 	if (skb->protocol == htons(ETH_P_IP))
2473 		dscp = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
2474 	else if (skb->protocol == htons(ETH_P_IPV6))
2475 		dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
2476 
2477 	return dcbcfg->dscp_map[dscp];
2478 }
2479 
2480 u16
2481 ice_select_queue(struct net_device *netdev, struct sk_buff *skb,
2482 		 struct net_device *sb_dev)
2483 {
2484 	struct ice_pf *pf = ice_netdev_to_pf(netdev);
2485 	struct ice_dcbx_cfg *dcbcfg;
2486 
2487 	dcbcfg = &pf->hw.port_info->qos_cfg.local_dcbx_cfg;
2488 	if (dcbcfg->pfc_mode == ICE_QOS_MODE_DSCP)
2489 		skb->priority = ice_get_dscp_up(dcbcfg, skb);
2490 
2491 	return netdev_pick_tx(netdev, skb, sb_dev);
2492 }
2493 
2494 /**
2495  * ice_clean_ctrl_tx_irq - interrupt handler for flow director Tx queue
2496  * @tx_ring: tx_ring to clean
2497  */
2498 void ice_clean_ctrl_tx_irq(struct ice_tx_ring *tx_ring)
2499 {
2500 	struct ice_vsi *vsi = tx_ring->vsi;
2501 	s16 i = tx_ring->next_to_clean;
2502 	int budget = ICE_DFLT_IRQ_WORK;
2503 	struct ice_tx_desc *tx_desc;
2504 	struct ice_tx_buf *tx_buf;
2505 
2506 	tx_buf = &tx_ring->tx_buf[i];
2507 	tx_desc = ICE_TX_DESC(tx_ring, i);
2508 	i -= tx_ring->count;
2509 
2510 	do {
2511 		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
2512 
2513 		/* if next_to_watch is not set then there is no pending work */
2514 		if (!eop_desc)
2515 			break;
2516 
2517 		/* prevent any other reads prior to eop_desc */
2518 		smp_rmb();
2519 
2520 		/* if the descriptor isn't done, no work to do */
2521 		if (!(eop_desc->cmd_type_offset_bsz &
2522 		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
2523 			break;
2524 
2525 		/* clear next_to_watch to prevent false hangs */
2526 		tx_buf->next_to_watch = NULL;
2527 		tx_desc->buf_addr = 0;
2528 		tx_desc->cmd_type_offset_bsz = 0;
2529 
2530 		/* move past filter desc */
2531 		tx_buf++;
2532 		tx_desc++;
2533 		i++;
2534 		if (unlikely(!i)) {
2535 			i -= tx_ring->count;
2536 			tx_buf = tx_ring->tx_buf;
2537 			tx_desc = ICE_TX_DESC(tx_ring, 0);
2538 		}
2539 
2540 		/* unmap the data header */
2541 		if (dma_unmap_len(tx_buf, len))
2542 			dma_unmap_single(tx_ring->dev,
2543 					 dma_unmap_addr(tx_buf, dma),
2544 					 dma_unmap_len(tx_buf, len),
2545 					 DMA_TO_DEVICE);
2546 		if (tx_buf->type == ICE_TX_BUF_DUMMY)
2547 			devm_kfree(tx_ring->dev, tx_buf->raw_buf);
2548 
2549 		/* clear next_to_watch to prevent false hangs */
2550 		tx_buf->type = ICE_TX_BUF_EMPTY;
2551 		tx_buf->tx_flags = 0;
2552 		tx_buf->next_to_watch = NULL;
2553 		dma_unmap_len_set(tx_buf, len, 0);
2554 		tx_desc->buf_addr = 0;
2555 		tx_desc->cmd_type_offset_bsz = 0;
2556 
2557 		/* move past eop_desc for start of next FD desc */
2558 		tx_buf++;
2559 		tx_desc++;
2560 		i++;
2561 		if (unlikely(!i)) {
2562 			i -= tx_ring->count;
2563 			tx_buf = tx_ring->tx_buf;
2564 			tx_desc = ICE_TX_DESC(tx_ring, 0);
2565 		}
2566 
2567 		budget--;
2568 	} while (likely(budget));
2569 
2570 	i += tx_ring->count;
2571 	tx_ring->next_to_clean = i;
2572 
2573 	/* re-enable interrupt if needed */
2574 	ice_irq_dynamic_ena(&vsi->back->hw, vsi, vsi->q_vectors[0]);
2575 }
2576