1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2018 Intel Corporation. */
3 
4 #include <linux/bpf_trace.h>
5 #include <net/xdp_sock.h>
6 #include <net/xdp.h>
7 
8 #include "i40e.h"
9 #include "i40e_txrx_common.h"
10 #include "i40e_xsk.h"
11 
12 /**
13  * i40e_xsk_umem_dma_map - DMA maps all UMEM memory for the netdev
14  * @vsi: Current VSI
15  * @umem: UMEM to DMA map
16  *
17  * Returns 0 on success, <0 on failure
18  **/
19 static int i40e_xsk_umem_dma_map(struct i40e_vsi *vsi, struct xdp_umem *umem)
20 {
21 	struct i40e_pf *pf = vsi->back;
22 	struct device *dev;
23 	unsigned int i, j;
24 	dma_addr_t dma;
25 
26 	dev = &pf->pdev->dev;
27 	for (i = 0; i < umem->npgs; i++) {
28 		dma = dma_map_page_attrs(dev, umem->pgs[i], 0, PAGE_SIZE,
29 					 DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
30 		if (dma_mapping_error(dev, dma))
31 			goto out_unmap;
32 
33 		umem->pages[i].dma = dma;
34 	}
35 
36 	return 0;
37 
38 out_unmap:
39 	for (j = 0; j < i; j++) {
40 		dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
41 				     DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
42 		umem->pages[i].dma = 0;
43 	}
44 
45 	return -1;
46 }
47 
48 /**
49  * i40e_xsk_umem_dma_unmap - DMA unmaps all UMEM memory for the netdev
50  * @vsi: Current VSI
51  * @umem: UMEM to DMA map
52  **/
53 static void i40e_xsk_umem_dma_unmap(struct i40e_vsi *vsi, struct xdp_umem *umem)
54 {
55 	struct i40e_pf *pf = vsi->back;
56 	struct device *dev;
57 	unsigned int i;
58 
59 	dev = &pf->pdev->dev;
60 
61 	for (i = 0; i < umem->npgs; i++) {
62 		dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
63 				     DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
64 
65 		umem->pages[i].dma = 0;
66 	}
67 }
68 
69 /**
70  * i40e_xsk_umem_enable - Enable/associate a UMEM to a certain ring/qid
71  * @vsi: Current VSI
72  * @umem: UMEM
73  * @qid: Rx ring to associate UMEM to
74  *
75  * Returns 0 on success, <0 on failure
76  **/
77 static int i40e_xsk_umem_enable(struct i40e_vsi *vsi, struct xdp_umem *umem,
78 				u16 qid)
79 {
80 	struct net_device *netdev = vsi->netdev;
81 	struct xdp_umem_fq_reuse *reuseq;
82 	bool if_running;
83 	int err;
84 
85 	if (vsi->type != I40E_VSI_MAIN)
86 		return -EINVAL;
87 
88 	if (qid >= vsi->num_queue_pairs)
89 		return -EINVAL;
90 
91 	if (qid >= netdev->real_num_rx_queues ||
92 	    qid >= netdev->real_num_tx_queues)
93 		return -EINVAL;
94 
95 	reuseq = xsk_reuseq_prepare(vsi->rx_rings[0]->count);
96 	if (!reuseq)
97 		return -ENOMEM;
98 
99 	xsk_reuseq_free(xsk_reuseq_swap(umem, reuseq));
100 
101 	err = i40e_xsk_umem_dma_map(vsi, umem);
102 	if (err)
103 		return err;
104 
105 	set_bit(qid, vsi->af_xdp_zc_qps);
106 
107 	if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
108 
109 	if (if_running) {
110 		err = i40e_queue_pair_disable(vsi, qid);
111 		if (err)
112 			return err;
113 
114 		err = i40e_queue_pair_enable(vsi, qid);
115 		if (err)
116 			return err;
117 
118 		/* Kick start the NAPI context so that receiving will start */
119 		err = i40e_xsk_wakeup(vsi->netdev, qid, XDP_WAKEUP_RX);
120 		if (err)
121 			return err;
122 	}
123 
124 	return 0;
125 }
126 
127 /**
128  * i40e_xsk_umem_disable - Disassociate a UMEM from a certain ring/qid
129  * @vsi: Current VSI
130  * @qid: Rx ring to associate UMEM to
131  *
132  * Returns 0 on success, <0 on failure
133  **/
134 static int i40e_xsk_umem_disable(struct i40e_vsi *vsi, u16 qid)
135 {
136 	struct net_device *netdev = vsi->netdev;
137 	struct xdp_umem *umem;
138 	bool if_running;
139 	int err;
140 
141 	umem = xdp_get_umem_from_qid(netdev, qid);
142 	if (!umem)
143 		return -EINVAL;
144 
145 	if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
146 
147 	if (if_running) {
148 		err = i40e_queue_pair_disable(vsi, qid);
149 		if (err)
150 			return err;
151 	}
152 
153 	clear_bit(qid, vsi->af_xdp_zc_qps);
154 	i40e_xsk_umem_dma_unmap(vsi, umem);
155 
156 	if (if_running) {
157 		err = i40e_queue_pair_enable(vsi, qid);
158 		if (err)
159 			return err;
160 
161 		/* Kick start the NAPI context so that receiving will start */
162 		err = i40e_xsk_wakeup(vsi->netdev, qid, XDP_WAKEUP_RX);
163 		if (err)
164 			return err;
165 	}
166 
167 	return 0;
168 }
169 
170 /**
171  * i40e_xsk_umem_setup - Enable/disassociate a UMEM to/from a ring/qid
172  * @vsi: Current VSI
173  * @umem: UMEM to enable/associate to a ring, or NULL to disable
174  * @qid: Rx ring to (dis)associate UMEM (from)to
175  *
176  * This function enables or disables a UMEM to a certain ring.
177  *
178  * Returns 0 on success, <0 on failure
179  **/
180 int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
181 			u16 qid)
182 {
183 	return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
184 		i40e_xsk_umem_disable(vsi, qid);
185 }
186 
187 /**
188  * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
189  * @rx_ring: Rx ring
190  * @xdp: xdp_buff used as input to the XDP program
191  *
192  * This function enables or disables a UMEM to a certain ring.
193  *
194  * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
195  **/
196 static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
197 {
198 	struct xdp_umem *umem = rx_ring->xsk_umem;
199 	int err, result = I40E_XDP_PASS;
200 	struct i40e_ring *xdp_ring;
201 	struct bpf_prog *xdp_prog;
202 	u64 offset;
203 	u32 act;
204 
205 	rcu_read_lock();
206 	/* NB! xdp_prog will always be !NULL, due to the fact that
207 	 * this path is enabled by setting an XDP program.
208 	 */
209 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
210 	act = bpf_prog_run_xdp(xdp_prog, xdp);
211 	offset = xdp->data - xdp->data_hard_start;
212 
213 	xdp->handle = xsk_umem_adjust_offset(umem, xdp->handle, offset);
214 
215 	switch (act) {
216 	case XDP_PASS:
217 		break;
218 	case XDP_TX:
219 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
220 		result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
221 		break;
222 	case XDP_REDIRECT:
223 		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
224 		result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
225 		break;
226 	default:
227 		bpf_warn_invalid_xdp_action(act);
228 		/* fall through */
229 	case XDP_ABORTED:
230 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
231 		/* fallthrough -- handle aborts by dropping packet */
232 	case XDP_DROP:
233 		result = I40E_XDP_CONSUMED;
234 		break;
235 	}
236 	rcu_read_unlock();
237 	return result;
238 }
239 
240 /**
241  * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
242  * @rx_ring: Rx ring
243  * @bi: Rx buffer to populate
244  *
245  * This function allocates an Rx buffer. The buffer can come from fill
246  * queue, or via the recycle queue (next_to_alloc).
247  *
248  * Returns true for a successful allocation, false otherwise
249  **/
250 static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
251 				 struct i40e_rx_buffer *bi)
252 {
253 	struct xdp_umem *umem = rx_ring->xsk_umem;
254 	void *addr = bi->addr;
255 	u64 handle, hr;
256 
257 	if (addr) {
258 		rx_ring->rx_stats.page_reuse_count++;
259 		return true;
260 	}
261 
262 	if (!xsk_umem_peek_addr(umem, &handle)) {
263 		rx_ring->rx_stats.alloc_page_failed++;
264 		return false;
265 	}
266 
267 	hr = umem->headroom + XDP_PACKET_HEADROOM;
268 
269 	bi->dma = xdp_umem_get_dma(umem, handle);
270 	bi->dma += hr;
271 
272 	bi->addr = xdp_umem_get_data(umem, handle);
273 	bi->addr += hr;
274 
275 	bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom);
276 
277 	xsk_umem_discard_addr(umem);
278 	return true;
279 }
280 
281 /**
282  * i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
283  * @rx_ring: Rx ring
284  * @bi: Rx buffer to populate
285  *
286  * This function allocates an Rx buffer. The buffer can come from fill
287  * queue, or via the reuse queue.
288  *
289  * Returns true for a successful allocation, false otherwise
290  **/
291 static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
292 				      struct i40e_rx_buffer *bi)
293 {
294 	struct xdp_umem *umem = rx_ring->xsk_umem;
295 	u64 handle, hr;
296 
297 	if (!xsk_umem_peek_addr_rq(umem, &handle)) {
298 		rx_ring->rx_stats.alloc_page_failed++;
299 		return false;
300 	}
301 
302 	handle &= rx_ring->xsk_umem->chunk_mask;
303 
304 	hr = umem->headroom + XDP_PACKET_HEADROOM;
305 
306 	bi->dma = xdp_umem_get_dma(umem, handle);
307 	bi->dma += hr;
308 
309 	bi->addr = xdp_umem_get_data(umem, handle);
310 	bi->addr += hr;
311 
312 	bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom);
313 
314 	xsk_umem_discard_addr_rq(umem);
315 	return true;
316 }
317 
318 static __always_inline bool
319 __i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
320 			   bool alloc(struct i40e_ring *rx_ring,
321 				      struct i40e_rx_buffer *bi))
322 {
323 	u16 ntu = rx_ring->next_to_use;
324 	union i40e_rx_desc *rx_desc;
325 	struct i40e_rx_buffer *bi;
326 	bool ok = true;
327 
328 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
329 	bi = &rx_ring->rx_bi[ntu];
330 	do {
331 		if (!alloc(rx_ring, bi)) {
332 			ok = false;
333 			goto no_buffers;
334 		}
335 
336 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
337 						 rx_ring->rx_buf_len,
338 						 DMA_BIDIRECTIONAL);
339 
340 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
341 
342 		rx_desc++;
343 		bi++;
344 		ntu++;
345 
346 		if (unlikely(ntu == rx_ring->count)) {
347 			rx_desc = I40E_RX_DESC(rx_ring, 0);
348 			bi = rx_ring->rx_bi;
349 			ntu = 0;
350 		}
351 
352 		rx_desc->wb.qword1.status_error_len = 0;
353 		count--;
354 	} while (count);
355 
356 no_buffers:
357 	if (rx_ring->next_to_use != ntu)
358 		i40e_release_rx_desc(rx_ring, ntu);
359 
360 	return ok;
361 }
362 
363 /**
364  * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
365  * @rx_ring: Rx ring
366  * @count: The number of buffers to allocate
367  *
368  * This function allocates a number of Rx buffers from the reuse queue
369  * or fill ring and places them on the Rx ring.
370  *
371  * Returns true for a successful allocation, false otherwise
372  **/
373 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
374 {
375 	return __i40e_alloc_rx_buffers_zc(rx_ring, count,
376 					  i40e_alloc_buffer_slow_zc);
377 }
378 
379 /**
380  * i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
381  * @rx_ring: Rx ring
382  * @count: The number of buffers to allocate
383  *
384  * This function allocates a number of Rx buffers from the fill ring
385  * or the internal recycle mechanism and places them on the Rx ring.
386  *
387  * Returns true for a successful allocation, false otherwise
388  **/
389 static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
390 {
391 	return __i40e_alloc_rx_buffers_zc(rx_ring, count,
392 					  i40e_alloc_buffer_zc);
393 }
394 
395 /**
396  * i40e_get_rx_buffer_zc - Return the current Rx buffer
397  * @rx_ring: Rx ring
398  * @size: The size of the rx buffer (read from descriptor)
399  *
400  * This function returns the current, received Rx buffer, and also
401  * does DMA synchronization.  the Rx ring.
402  *
403  * Returns the received Rx buffer
404  **/
405 static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
406 						    const unsigned int size)
407 {
408 	struct i40e_rx_buffer *bi;
409 
410 	bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
411 
412 	/* we are reusing so sync this buffer for CPU use */
413 	dma_sync_single_range_for_cpu(rx_ring->dev,
414 				      bi->dma, 0,
415 				      size,
416 				      DMA_BIDIRECTIONAL);
417 
418 	return bi;
419 }
420 
421 /**
422  * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
423  * @rx_ring: Rx ring
424  * @old_bi: The Rx buffer to recycle
425  *
426  * This function recycles a finished Rx buffer, and places it on the
427  * recycle queue (next_to_alloc).
428  **/
429 static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
430 				    struct i40e_rx_buffer *old_bi)
431 {
432 	struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
433 	u16 nta = rx_ring->next_to_alloc;
434 
435 	/* update, and store next to alloc */
436 	nta++;
437 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
438 
439 	/* transfer page from old buffer to new buffer */
440 	new_bi->dma = old_bi->dma;
441 	new_bi->addr = old_bi->addr;
442 	new_bi->handle = old_bi->handle;
443 
444 	old_bi->addr = NULL;
445 }
446 
447 /**
448  * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
449  * @alloc: Zero-copy allocator
450  * @handle: Buffer handle
451  **/
452 void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
453 {
454 	struct i40e_rx_buffer *bi;
455 	struct i40e_ring *rx_ring;
456 	u64 hr, mask;
457 	u16 nta;
458 
459 	rx_ring = container_of(alloc, struct i40e_ring, zca);
460 	hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
461 	mask = rx_ring->xsk_umem->chunk_mask;
462 
463 	nta = rx_ring->next_to_alloc;
464 	bi = &rx_ring->rx_bi[nta];
465 
466 	nta++;
467 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
468 
469 	handle &= mask;
470 
471 	bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
472 	bi->dma += hr;
473 
474 	bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
475 	bi->addr += hr;
476 
477 	bi->handle = xsk_umem_adjust_offset(rx_ring->xsk_umem, (u64)handle,
478 					    rx_ring->xsk_umem->headroom);
479 }
480 
481 /**
482  * i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
483  * @rx_ring: Rx ring
484  * @bi: Rx buffer
485  * @xdp: xdp_buff
486  *
487  * This functions allocates a new skb from a zero-copy Rx buffer.
488  *
489  * Returns the skb, or NULL on failure.
490  **/
491 static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
492 					     struct i40e_rx_buffer *bi,
493 					     struct xdp_buff *xdp)
494 {
495 	unsigned int metasize = xdp->data - xdp->data_meta;
496 	unsigned int datasize = xdp->data_end - xdp->data;
497 	struct sk_buff *skb;
498 
499 	/* allocate a skb to store the frags */
500 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
501 			       xdp->data_end - xdp->data_hard_start,
502 			       GFP_ATOMIC | __GFP_NOWARN);
503 	if (unlikely(!skb))
504 		return NULL;
505 
506 	skb_reserve(skb, xdp->data - xdp->data_hard_start);
507 	memcpy(__skb_put(skb, datasize), xdp->data, datasize);
508 	if (metasize)
509 		skb_metadata_set(skb, metasize);
510 
511 	i40e_reuse_rx_buffer_zc(rx_ring, bi);
512 	return skb;
513 }
514 
515 /**
516  * i40e_inc_ntc: Advance the next_to_clean index
517  * @rx_ring: Rx ring
518  **/
519 static void i40e_inc_ntc(struct i40e_ring *rx_ring)
520 {
521 	u32 ntc = rx_ring->next_to_clean + 1;
522 
523 	ntc = (ntc < rx_ring->count) ? ntc : 0;
524 	rx_ring->next_to_clean = ntc;
525 	prefetch(I40E_RX_DESC(rx_ring, ntc));
526 }
527 
528 /**
529  * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
530  * @rx_ring: Rx ring
531  * @budget: NAPI budget
532  *
533  * Returns amount of work completed
534  **/
535 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
536 {
537 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
538 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
539 	unsigned int xdp_res, xdp_xmit = 0;
540 	bool failure = false;
541 	struct sk_buff *skb;
542 	struct xdp_buff xdp;
543 
544 	xdp.rxq = &rx_ring->xdp_rxq;
545 
546 	while (likely(total_rx_packets < (unsigned int)budget)) {
547 		struct i40e_rx_buffer *bi;
548 		union i40e_rx_desc *rx_desc;
549 		unsigned int size;
550 		u64 qword;
551 
552 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
553 			failure = failure ||
554 				  !i40e_alloc_rx_buffers_fast_zc(rx_ring,
555 								 cleaned_count);
556 			cleaned_count = 0;
557 		}
558 
559 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
560 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
561 
562 		/* This memory barrier is needed to keep us from reading
563 		 * any other fields out of the rx_desc until we have
564 		 * verified the descriptor has been written back.
565 		 */
566 		dma_rmb();
567 
568 		bi = i40e_clean_programming_status(rx_ring, rx_desc,
569 						   qword);
570 		if (unlikely(bi)) {
571 			i40e_reuse_rx_buffer_zc(rx_ring, bi);
572 			cleaned_count++;
573 			continue;
574 		}
575 
576 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
577 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
578 		if (!size)
579 			break;
580 
581 		bi = i40e_get_rx_buffer_zc(rx_ring, size);
582 		xdp.data = bi->addr;
583 		xdp.data_meta = xdp.data;
584 		xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
585 		xdp.data_end = xdp.data + size;
586 		xdp.handle = bi->handle;
587 
588 		xdp_res = i40e_run_xdp_zc(rx_ring, &xdp);
589 		if (xdp_res) {
590 			if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
591 				xdp_xmit |= xdp_res;
592 				bi->addr = NULL;
593 			} else {
594 				i40e_reuse_rx_buffer_zc(rx_ring, bi);
595 			}
596 
597 			total_rx_bytes += size;
598 			total_rx_packets++;
599 
600 			cleaned_count++;
601 			i40e_inc_ntc(rx_ring);
602 			continue;
603 		}
604 
605 		/* XDP_PASS path */
606 
607 		/* NB! We are not checking for errors using
608 		 * i40e_test_staterr with
609 		 * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
610 		 * SBP is *not* set in PRT_SBPVSI (default not set).
611 		 */
612 		skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
613 		if (!skb) {
614 			rx_ring->rx_stats.alloc_buff_failed++;
615 			break;
616 		}
617 
618 		cleaned_count++;
619 		i40e_inc_ntc(rx_ring);
620 
621 		if (eth_skb_pad(skb))
622 			continue;
623 
624 		total_rx_bytes += skb->len;
625 		total_rx_packets++;
626 
627 		i40e_process_skb_fields(rx_ring, rx_desc, skb);
628 		napi_gro_receive(&rx_ring->q_vector->napi, skb);
629 	}
630 
631 	i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
632 	i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
633 
634 	if (xsk_umem_uses_need_wakeup(rx_ring->xsk_umem)) {
635 		if (failure || rx_ring->next_to_clean == rx_ring->next_to_use)
636 			xsk_set_rx_need_wakeup(rx_ring->xsk_umem);
637 		else
638 			xsk_clear_rx_need_wakeup(rx_ring->xsk_umem);
639 
640 		return (int)total_rx_packets;
641 	}
642 	return failure ? budget : (int)total_rx_packets;
643 }
644 
645 /**
646  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
647  * @xdp_ring: XDP Tx ring
648  * @budget: NAPI budget
649  *
650  * Returns true if the work is finished.
651  **/
652 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
653 {
654 	struct i40e_tx_desc *tx_desc = NULL;
655 	struct i40e_tx_buffer *tx_bi;
656 	bool work_done = true;
657 	struct xdp_desc desc;
658 	dma_addr_t dma;
659 
660 	while (budget-- > 0) {
661 		if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
662 			xdp_ring->tx_stats.tx_busy++;
663 			work_done = false;
664 			break;
665 		}
666 
667 		if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &desc))
668 			break;
669 
670 		dma = xdp_umem_get_dma(xdp_ring->xsk_umem, desc.addr);
671 
672 		dma_sync_single_for_device(xdp_ring->dev, dma, desc.len,
673 					   DMA_BIDIRECTIONAL);
674 
675 		tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
676 		tx_bi->bytecount = desc.len;
677 
678 		tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
679 		tx_desc->buffer_addr = cpu_to_le64(dma);
680 		tx_desc->cmd_type_offset_bsz =
681 			build_ctob(I40E_TX_DESC_CMD_ICRC
682 				   | I40E_TX_DESC_CMD_EOP,
683 				   0, desc.len, 0);
684 
685 		xdp_ring->next_to_use++;
686 		if (xdp_ring->next_to_use == xdp_ring->count)
687 			xdp_ring->next_to_use = 0;
688 	}
689 
690 	if (tx_desc) {
691 		/* Request an interrupt for the last frame and bump tail ptr. */
692 		tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
693 						 I40E_TXD_QW1_CMD_SHIFT);
694 		i40e_xdp_ring_update_tail(xdp_ring);
695 
696 		xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
697 		if (xsk_umem_uses_need_wakeup(xdp_ring->xsk_umem))
698 			xsk_clear_tx_need_wakeup(xdp_ring->xsk_umem);
699 	}
700 
701 	return !!budget && work_done;
702 }
703 
704 /**
705  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
706  * @tx_ring: XDP Tx ring
707  * @tx_bi: Tx buffer info to clean
708  **/
709 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
710 				     struct i40e_tx_buffer *tx_bi)
711 {
712 	xdp_return_frame(tx_bi->xdpf);
713 	dma_unmap_single(tx_ring->dev,
714 			 dma_unmap_addr(tx_bi, dma),
715 			 dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
716 	dma_unmap_len_set(tx_bi, len, 0);
717 }
718 
719 /**
720  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
721  * @tx_ring: XDP Tx ring
722  * @tx_bi: Tx buffer info to clean
723  *
724  * Returns true if cleanup/tranmission is done.
725  **/
726 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
727 			   struct i40e_ring *tx_ring, int napi_budget)
728 {
729 	unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
730 	u32 i, completed_frames, frames_ready, xsk_frames = 0;
731 	struct xdp_umem *umem = tx_ring->xsk_umem;
732 	u32 head_idx = i40e_get_head(tx_ring);
733 	bool work_done = true, xmit_done;
734 	struct i40e_tx_buffer *tx_bi;
735 
736 	if (head_idx < tx_ring->next_to_clean)
737 		head_idx += tx_ring->count;
738 	frames_ready = head_idx - tx_ring->next_to_clean;
739 
740 	if (frames_ready == 0) {
741 		goto out_xmit;
742 	} else if (frames_ready > budget) {
743 		completed_frames = budget;
744 		work_done = false;
745 	} else {
746 		completed_frames = frames_ready;
747 	}
748 
749 	ntc = tx_ring->next_to_clean;
750 
751 	for (i = 0; i < completed_frames; i++) {
752 		tx_bi = &tx_ring->tx_bi[ntc];
753 
754 		if (tx_bi->xdpf)
755 			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
756 		else
757 			xsk_frames++;
758 
759 		tx_bi->xdpf = NULL;
760 		total_bytes += tx_bi->bytecount;
761 
762 		if (++ntc >= tx_ring->count)
763 			ntc = 0;
764 	}
765 
766 	tx_ring->next_to_clean += completed_frames;
767 	if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
768 		tx_ring->next_to_clean -= tx_ring->count;
769 
770 	if (xsk_frames)
771 		xsk_umem_complete_tx(umem, xsk_frames);
772 
773 	i40e_arm_wb(tx_ring, vsi, budget);
774 	i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
775 
776 out_xmit:
777 	if (xsk_umem_uses_need_wakeup(tx_ring->xsk_umem)) {
778 		if (tx_ring->next_to_clean == tx_ring->next_to_use)
779 			xsk_set_tx_need_wakeup(tx_ring->xsk_umem);
780 		else
781 			xsk_clear_tx_need_wakeup(tx_ring->xsk_umem);
782 	}
783 
784 	xmit_done = i40e_xmit_zc(tx_ring, budget);
785 
786 	return work_done && xmit_done;
787 }
788 
789 /**
790  * i40e_xsk_wakeup - Implements the ndo_xsk_wakeup
791  * @dev: the netdevice
792  * @queue_id: queue id to wake up
793  * @flags: ignored in our case since we have Rx and Tx in the same NAPI.
794  *
795  * Returns <0 for errors, 0 otherwise.
796  **/
797 int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
798 {
799 	struct i40e_netdev_priv *np = netdev_priv(dev);
800 	struct i40e_vsi *vsi = np->vsi;
801 	struct i40e_ring *ring;
802 
803 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
804 		return -ENETDOWN;
805 
806 	if (!i40e_enabled_xdp_vsi(vsi))
807 		return -ENXIO;
808 
809 	if (queue_id >= vsi->num_queue_pairs)
810 		return -ENXIO;
811 
812 	if (!vsi->xdp_rings[queue_id]->xsk_umem)
813 		return -ENXIO;
814 
815 	ring = vsi->xdp_rings[queue_id];
816 
817 	/* The idea here is that if NAPI is running, mark a miss, so
818 	 * it will run again. If not, trigger an interrupt and
819 	 * schedule the NAPI from interrupt context. If NAPI would be
820 	 * scheduled here, the interrupt affinity would not be
821 	 * honored.
822 	 */
823 	if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
824 		i40e_force_wb(vsi, ring->q_vector);
825 
826 	return 0;
827 }
828 
829 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
830 {
831 	u16 i;
832 
833 	for (i = 0; i < rx_ring->count; i++) {
834 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
835 
836 		if (!rx_bi->addr)
837 			continue;
838 
839 		xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
840 		rx_bi->addr = NULL;
841 	}
842 }
843 
844 /**
845  * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
846  * @xdp_ring: XDP Tx ring
847  **/
848 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
849 {
850 	u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
851 	struct xdp_umem *umem = tx_ring->xsk_umem;
852 	struct i40e_tx_buffer *tx_bi;
853 	u32 xsk_frames = 0;
854 
855 	while (ntc != ntu) {
856 		tx_bi = &tx_ring->tx_bi[ntc];
857 
858 		if (tx_bi->xdpf)
859 			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
860 		else
861 			xsk_frames++;
862 
863 		tx_bi->xdpf = NULL;
864 
865 		ntc++;
866 		if (ntc >= tx_ring->count)
867 			ntc = 0;
868 	}
869 
870 	if (xsk_frames)
871 		xsk_umem_complete_tx(umem, xsk_frames);
872 }
873 
874 /**
875  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
876  * @vsi: vsi
877  *
878  * Returns true if any of the Rx rings has an AF_XDP UMEM attached
879  **/
880 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
881 {
882 	struct net_device *netdev = vsi->netdev;
883 	int i;
884 
885 	for (i = 0; i < vsi->num_queue_pairs; i++) {
886 		if (xdp_get_umem_from_qid(netdev, i))
887 			return true;
888 	}
889 
890 	return false;
891 }
892