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 
162 	return 0;
163 }
164 
165 /**
166  * i40e_xsk_umem_setup - Enable/disassociate a UMEM to/from a ring/qid
167  * @vsi: Current VSI
168  * @umem: UMEM to enable/associate to a ring, or NULL to disable
169  * @qid: Rx ring to (dis)associate UMEM (from)to
170  *
171  * This function enables or disables a UMEM to a certain ring.
172  *
173  * Returns 0 on success, <0 on failure
174  **/
175 int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
176 			u16 qid)
177 {
178 	return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
179 		i40e_xsk_umem_disable(vsi, qid);
180 }
181 
182 /**
183  * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
184  * @rx_ring: Rx ring
185  * @xdp: xdp_buff used as input to the XDP program
186  *
187  * This function enables or disables a UMEM to a certain ring.
188  *
189  * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
190  **/
191 static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
192 {
193 	struct xdp_umem *umem = rx_ring->xsk_umem;
194 	int err, result = I40E_XDP_PASS;
195 	struct i40e_ring *xdp_ring;
196 	struct bpf_prog *xdp_prog;
197 	u64 offset;
198 	u32 act;
199 
200 	rcu_read_lock();
201 	/* NB! xdp_prog will always be !NULL, due to the fact that
202 	 * this path is enabled by setting an XDP program.
203 	 */
204 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
205 	act = bpf_prog_run_xdp(xdp_prog, xdp);
206 	offset = xdp->data - xdp->data_hard_start;
207 
208 	xdp->handle = xsk_umem_adjust_offset(umem, xdp->handle, offset);
209 
210 	switch (act) {
211 	case XDP_PASS:
212 		break;
213 	case XDP_TX:
214 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
215 		result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
216 		break;
217 	case XDP_REDIRECT:
218 		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
219 		result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
220 		break;
221 	default:
222 		bpf_warn_invalid_xdp_action(act);
223 		/* fall through */
224 	case XDP_ABORTED:
225 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
226 		/* fallthrough -- handle aborts by dropping packet */
227 	case XDP_DROP:
228 		result = I40E_XDP_CONSUMED;
229 		break;
230 	}
231 	rcu_read_unlock();
232 	return result;
233 }
234 
235 /**
236  * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
237  * @rx_ring: Rx ring
238  * @bi: Rx buffer to populate
239  *
240  * This function allocates an Rx buffer. The buffer can come from fill
241  * queue, or via the recycle queue (next_to_alloc).
242  *
243  * Returns true for a successful allocation, false otherwise
244  **/
245 static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
246 				 struct i40e_rx_buffer *bi)
247 {
248 	struct xdp_umem *umem = rx_ring->xsk_umem;
249 	void *addr = bi->addr;
250 	u64 handle, hr;
251 
252 	if (addr) {
253 		rx_ring->rx_stats.page_reuse_count++;
254 		return true;
255 	}
256 
257 	if (!xsk_umem_peek_addr(umem, &handle)) {
258 		rx_ring->rx_stats.alloc_page_failed++;
259 		return false;
260 	}
261 
262 	hr = umem->headroom + XDP_PACKET_HEADROOM;
263 
264 	bi->dma = xdp_umem_get_dma(umem, handle);
265 	bi->dma += hr;
266 
267 	bi->addr = xdp_umem_get_data(umem, handle);
268 	bi->addr += hr;
269 
270 	bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom);
271 
272 	xsk_umem_release_addr(umem);
273 	return true;
274 }
275 
276 /**
277  * i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
278  * @rx_ring: Rx ring
279  * @bi: Rx buffer to populate
280  *
281  * This function allocates an Rx buffer. The buffer can come from fill
282  * queue, or via the reuse queue.
283  *
284  * Returns true for a successful allocation, false otherwise
285  **/
286 static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
287 				      struct i40e_rx_buffer *bi)
288 {
289 	struct xdp_umem *umem = rx_ring->xsk_umem;
290 	u64 handle, hr;
291 
292 	if (!xsk_umem_peek_addr_rq(umem, &handle)) {
293 		rx_ring->rx_stats.alloc_page_failed++;
294 		return false;
295 	}
296 
297 	handle &= rx_ring->xsk_umem->chunk_mask;
298 
299 	hr = umem->headroom + XDP_PACKET_HEADROOM;
300 
301 	bi->dma = xdp_umem_get_dma(umem, handle);
302 	bi->dma += hr;
303 
304 	bi->addr = xdp_umem_get_data(umem, handle);
305 	bi->addr += hr;
306 
307 	bi->handle = xsk_umem_adjust_offset(umem, handle, umem->headroom);
308 
309 	xsk_umem_release_addr_rq(umem);
310 	return true;
311 }
312 
313 static __always_inline bool
314 __i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
315 			   bool alloc(struct i40e_ring *rx_ring,
316 				      struct i40e_rx_buffer *bi))
317 {
318 	u16 ntu = rx_ring->next_to_use;
319 	union i40e_rx_desc *rx_desc;
320 	struct i40e_rx_buffer *bi;
321 	bool ok = true;
322 
323 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
324 	bi = &rx_ring->rx_bi[ntu];
325 	do {
326 		if (!alloc(rx_ring, bi)) {
327 			ok = false;
328 			goto no_buffers;
329 		}
330 
331 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
332 						 rx_ring->rx_buf_len,
333 						 DMA_BIDIRECTIONAL);
334 
335 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
336 
337 		rx_desc++;
338 		bi++;
339 		ntu++;
340 
341 		if (unlikely(ntu == rx_ring->count)) {
342 			rx_desc = I40E_RX_DESC(rx_ring, 0);
343 			bi = rx_ring->rx_bi;
344 			ntu = 0;
345 		}
346 
347 		rx_desc->wb.qword1.status_error_len = 0;
348 		count--;
349 	} while (count);
350 
351 no_buffers:
352 	if (rx_ring->next_to_use != ntu)
353 		i40e_release_rx_desc(rx_ring, ntu);
354 
355 	return ok;
356 }
357 
358 /**
359  * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
360  * @rx_ring: Rx ring
361  * @count: The number of buffers to allocate
362  *
363  * This function allocates a number of Rx buffers from the reuse queue
364  * or fill ring and places them on the Rx ring.
365  *
366  * Returns true for a successful allocation, false otherwise
367  **/
368 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
369 {
370 	return __i40e_alloc_rx_buffers_zc(rx_ring, count,
371 					  i40e_alloc_buffer_slow_zc);
372 }
373 
374 /**
375  * i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
376  * @rx_ring: Rx ring
377  * @count: The number of buffers to allocate
378  *
379  * This function allocates a number of Rx buffers from the fill ring
380  * or the internal recycle mechanism and places them on the Rx ring.
381  *
382  * Returns true for a successful allocation, false otherwise
383  **/
384 static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
385 {
386 	return __i40e_alloc_rx_buffers_zc(rx_ring, count,
387 					  i40e_alloc_buffer_zc);
388 }
389 
390 /**
391  * i40e_get_rx_buffer_zc - Return the current Rx buffer
392  * @rx_ring: Rx ring
393  * @size: The size of the rx buffer (read from descriptor)
394  *
395  * This function returns the current, received Rx buffer, and also
396  * does DMA synchronization.  the Rx ring.
397  *
398  * Returns the received Rx buffer
399  **/
400 static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
401 						    const unsigned int size)
402 {
403 	struct i40e_rx_buffer *bi;
404 
405 	bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
406 
407 	/* we are reusing so sync this buffer for CPU use */
408 	dma_sync_single_range_for_cpu(rx_ring->dev,
409 				      bi->dma, 0,
410 				      size,
411 				      DMA_BIDIRECTIONAL);
412 
413 	return bi;
414 }
415 
416 /**
417  * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
418  * @rx_ring: Rx ring
419  * @old_bi: The Rx buffer to recycle
420  *
421  * This function recycles a finished Rx buffer, and places it on the
422  * recycle queue (next_to_alloc).
423  **/
424 static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
425 				    struct i40e_rx_buffer *old_bi)
426 {
427 	struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
428 	u16 nta = rx_ring->next_to_alloc;
429 
430 	/* update, and store next to alloc */
431 	nta++;
432 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
433 
434 	/* transfer page from old buffer to new buffer */
435 	new_bi->dma = old_bi->dma;
436 	new_bi->addr = old_bi->addr;
437 	new_bi->handle = old_bi->handle;
438 
439 	old_bi->addr = NULL;
440 }
441 
442 /**
443  * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
444  * @alloc: Zero-copy allocator
445  * @handle: Buffer handle
446  **/
447 void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
448 {
449 	struct i40e_rx_buffer *bi;
450 	struct i40e_ring *rx_ring;
451 	u64 hr, mask;
452 	u16 nta;
453 
454 	rx_ring = container_of(alloc, struct i40e_ring, zca);
455 	hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
456 	mask = rx_ring->xsk_umem->chunk_mask;
457 
458 	nta = rx_ring->next_to_alloc;
459 	bi = &rx_ring->rx_bi[nta];
460 
461 	nta++;
462 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
463 
464 	handle &= mask;
465 
466 	bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
467 	bi->dma += hr;
468 
469 	bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
470 	bi->addr += hr;
471 
472 	bi->handle = xsk_umem_adjust_offset(rx_ring->xsk_umem, (u64)handle,
473 					    rx_ring->xsk_umem->headroom);
474 }
475 
476 /**
477  * i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
478  * @rx_ring: Rx ring
479  * @bi: Rx buffer
480  * @xdp: xdp_buff
481  *
482  * This functions allocates a new skb from a zero-copy Rx buffer.
483  *
484  * Returns the skb, or NULL on failure.
485  **/
486 static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
487 					     struct i40e_rx_buffer *bi,
488 					     struct xdp_buff *xdp)
489 {
490 	unsigned int metasize = xdp->data - xdp->data_meta;
491 	unsigned int datasize = xdp->data_end - xdp->data;
492 	struct sk_buff *skb;
493 
494 	/* allocate a skb to store the frags */
495 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
496 			       xdp->data_end - xdp->data_hard_start,
497 			       GFP_ATOMIC | __GFP_NOWARN);
498 	if (unlikely(!skb))
499 		return NULL;
500 
501 	skb_reserve(skb, xdp->data - xdp->data_hard_start);
502 	memcpy(__skb_put(skb, datasize), xdp->data, datasize);
503 	if (metasize)
504 		skb_metadata_set(skb, metasize);
505 
506 	i40e_reuse_rx_buffer_zc(rx_ring, bi);
507 	return skb;
508 }
509 
510 /**
511  * i40e_inc_ntc: Advance the next_to_clean index
512  * @rx_ring: Rx ring
513  **/
514 static void i40e_inc_ntc(struct i40e_ring *rx_ring)
515 {
516 	u32 ntc = rx_ring->next_to_clean + 1;
517 
518 	ntc = (ntc < rx_ring->count) ? ntc : 0;
519 	rx_ring->next_to_clean = ntc;
520 	prefetch(I40E_RX_DESC(rx_ring, ntc));
521 }
522 
523 /**
524  * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
525  * @rx_ring: Rx ring
526  * @budget: NAPI budget
527  *
528  * Returns amount of work completed
529  **/
530 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
531 {
532 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
533 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
534 	unsigned int xdp_res, xdp_xmit = 0;
535 	bool failure = false;
536 	struct sk_buff *skb;
537 	struct xdp_buff xdp;
538 
539 	xdp.rxq = &rx_ring->xdp_rxq;
540 
541 	while (likely(total_rx_packets < (unsigned int)budget)) {
542 		struct i40e_rx_buffer *bi;
543 		union i40e_rx_desc *rx_desc;
544 		unsigned int size;
545 		u64 qword;
546 
547 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
548 			failure = failure ||
549 				  !i40e_alloc_rx_buffers_fast_zc(rx_ring,
550 								 cleaned_count);
551 			cleaned_count = 0;
552 		}
553 
554 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
555 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
556 
557 		/* This memory barrier is needed to keep us from reading
558 		 * any other fields out of the rx_desc until we have
559 		 * verified the descriptor has been written back.
560 		 */
561 		dma_rmb();
562 
563 		bi = i40e_clean_programming_status(rx_ring, rx_desc,
564 						   qword);
565 		if (unlikely(bi)) {
566 			i40e_reuse_rx_buffer_zc(rx_ring, bi);
567 			cleaned_count++;
568 			continue;
569 		}
570 
571 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
572 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
573 		if (!size)
574 			break;
575 
576 		bi = i40e_get_rx_buffer_zc(rx_ring, size);
577 		xdp.data = bi->addr;
578 		xdp.data_meta = xdp.data;
579 		xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
580 		xdp.data_end = xdp.data + size;
581 		xdp.handle = bi->handle;
582 
583 		xdp_res = i40e_run_xdp_zc(rx_ring, &xdp);
584 		if (xdp_res) {
585 			if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
586 				xdp_xmit |= xdp_res;
587 				bi->addr = NULL;
588 			} else {
589 				i40e_reuse_rx_buffer_zc(rx_ring, bi);
590 			}
591 
592 			total_rx_bytes += size;
593 			total_rx_packets++;
594 
595 			cleaned_count++;
596 			i40e_inc_ntc(rx_ring);
597 			continue;
598 		}
599 
600 		/* XDP_PASS path */
601 
602 		/* NB! We are not checking for errors using
603 		 * i40e_test_staterr with
604 		 * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
605 		 * SBP is *not* set in PRT_SBPVSI (default not set).
606 		 */
607 		skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
608 		if (!skb) {
609 			rx_ring->rx_stats.alloc_buff_failed++;
610 			break;
611 		}
612 
613 		cleaned_count++;
614 		i40e_inc_ntc(rx_ring);
615 
616 		if (eth_skb_pad(skb))
617 			continue;
618 
619 		total_rx_bytes += skb->len;
620 		total_rx_packets++;
621 
622 		i40e_process_skb_fields(rx_ring, rx_desc, skb);
623 		napi_gro_receive(&rx_ring->q_vector->napi, skb);
624 	}
625 
626 	i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
627 	i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
628 
629 	if (xsk_umem_uses_need_wakeup(rx_ring->xsk_umem)) {
630 		if (failure || rx_ring->next_to_clean == rx_ring->next_to_use)
631 			xsk_set_rx_need_wakeup(rx_ring->xsk_umem);
632 		else
633 			xsk_clear_rx_need_wakeup(rx_ring->xsk_umem);
634 
635 		return (int)total_rx_packets;
636 	}
637 	return failure ? budget : (int)total_rx_packets;
638 }
639 
640 /**
641  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
642  * @xdp_ring: XDP Tx ring
643  * @budget: NAPI budget
644  *
645  * Returns true if the work is finished.
646  **/
647 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
648 {
649 	struct i40e_tx_desc *tx_desc = NULL;
650 	struct i40e_tx_buffer *tx_bi;
651 	bool work_done = true;
652 	struct xdp_desc desc;
653 	dma_addr_t dma;
654 
655 	while (budget-- > 0) {
656 		if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
657 			xdp_ring->tx_stats.tx_busy++;
658 			work_done = false;
659 			break;
660 		}
661 
662 		if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &desc))
663 			break;
664 
665 		dma = xdp_umem_get_dma(xdp_ring->xsk_umem, desc.addr);
666 
667 		dma_sync_single_for_device(xdp_ring->dev, dma, desc.len,
668 					   DMA_BIDIRECTIONAL);
669 
670 		tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
671 		tx_bi->bytecount = desc.len;
672 
673 		tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
674 		tx_desc->buffer_addr = cpu_to_le64(dma);
675 		tx_desc->cmd_type_offset_bsz =
676 			build_ctob(I40E_TX_DESC_CMD_ICRC
677 				   | I40E_TX_DESC_CMD_EOP,
678 				   0, desc.len, 0);
679 
680 		xdp_ring->next_to_use++;
681 		if (xdp_ring->next_to_use == xdp_ring->count)
682 			xdp_ring->next_to_use = 0;
683 	}
684 
685 	if (tx_desc) {
686 		/* Request an interrupt for the last frame and bump tail ptr. */
687 		tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
688 						 I40E_TXD_QW1_CMD_SHIFT);
689 		i40e_xdp_ring_update_tail(xdp_ring);
690 
691 		xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
692 	}
693 
694 	return !!budget && work_done;
695 }
696 
697 /**
698  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
699  * @tx_ring: XDP Tx ring
700  * @tx_bi: Tx buffer info to clean
701  **/
702 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
703 				     struct i40e_tx_buffer *tx_bi)
704 {
705 	xdp_return_frame(tx_bi->xdpf);
706 	dma_unmap_single(tx_ring->dev,
707 			 dma_unmap_addr(tx_bi, dma),
708 			 dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
709 	dma_unmap_len_set(tx_bi, len, 0);
710 }
711 
712 /**
713  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
714  * @tx_ring: XDP Tx ring
715  * @tx_bi: Tx buffer info to clean
716  *
717  * Returns true if cleanup/tranmission is done.
718  **/
719 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
720 			   struct i40e_ring *tx_ring, int napi_budget)
721 {
722 	unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
723 	u32 i, completed_frames, frames_ready, xsk_frames = 0;
724 	struct xdp_umem *umem = tx_ring->xsk_umem;
725 	u32 head_idx = i40e_get_head(tx_ring);
726 	bool work_done = true, xmit_done;
727 	struct i40e_tx_buffer *tx_bi;
728 
729 	if (head_idx < tx_ring->next_to_clean)
730 		head_idx += tx_ring->count;
731 	frames_ready = head_idx - tx_ring->next_to_clean;
732 
733 	if (frames_ready == 0) {
734 		goto out_xmit;
735 	} else if (frames_ready > budget) {
736 		completed_frames = budget;
737 		work_done = false;
738 	} else {
739 		completed_frames = frames_ready;
740 	}
741 
742 	ntc = tx_ring->next_to_clean;
743 
744 	for (i = 0; i < completed_frames; i++) {
745 		tx_bi = &tx_ring->tx_bi[ntc];
746 
747 		if (tx_bi->xdpf)
748 			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
749 		else
750 			xsk_frames++;
751 
752 		tx_bi->xdpf = NULL;
753 		total_bytes += tx_bi->bytecount;
754 
755 		if (++ntc >= tx_ring->count)
756 			ntc = 0;
757 	}
758 
759 	tx_ring->next_to_clean += completed_frames;
760 	if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
761 		tx_ring->next_to_clean -= tx_ring->count;
762 
763 	if (xsk_frames)
764 		xsk_umem_complete_tx(umem, xsk_frames);
765 
766 	i40e_arm_wb(tx_ring, vsi, budget);
767 	i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
768 
769 out_xmit:
770 	if (xsk_umem_uses_need_wakeup(tx_ring->xsk_umem))
771 		xsk_set_tx_need_wakeup(tx_ring->xsk_umem);
772 
773 	xmit_done = i40e_xmit_zc(tx_ring, budget);
774 
775 	return work_done && xmit_done;
776 }
777 
778 /**
779  * i40e_xsk_wakeup - Implements the ndo_xsk_wakeup
780  * @dev: the netdevice
781  * @queue_id: queue id to wake up
782  * @flags: ignored in our case since we have Rx and Tx in the same NAPI.
783  *
784  * Returns <0 for errors, 0 otherwise.
785  **/
786 int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
787 {
788 	struct i40e_netdev_priv *np = netdev_priv(dev);
789 	struct i40e_vsi *vsi = np->vsi;
790 	struct i40e_pf *pf = vsi->back;
791 	struct i40e_ring *ring;
792 
793 	if (test_bit(__I40E_CONFIG_BUSY, pf->state))
794 		return -EAGAIN;
795 
796 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
797 		return -ENETDOWN;
798 
799 	if (!i40e_enabled_xdp_vsi(vsi))
800 		return -ENXIO;
801 
802 	if (queue_id >= vsi->num_queue_pairs)
803 		return -ENXIO;
804 
805 	if (!vsi->xdp_rings[queue_id]->xsk_umem)
806 		return -ENXIO;
807 
808 	ring = vsi->xdp_rings[queue_id];
809 
810 	/* The idea here is that if NAPI is running, mark a miss, so
811 	 * it will run again. If not, trigger an interrupt and
812 	 * schedule the NAPI from interrupt context. If NAPI would be
813 	 * scheduled here, the interrupt affinity would not be
814 	 * honored.
815 	 */
816 	if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
817 		i40e_force_wb(vsi, ring->q_vector);
818 
819 	return 0;
820 }
821 
822 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
823 {
824 	u16 i;
825 
826 	for (i = 0; i < rx_ring->count; i++) {
827 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
828 
829 		if (!rx_bi->addr)
830 			continue;
831 
832 		xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
833 		rx_bi->addr = NULL;
834 	}
835 }
836 
837 /**
838  * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
839  * @xdp_ring: XDP Tx ring
840  **/
841 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
842 {
843 	u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
844 	struct xdp_umem *umem = tx_ring->xsk_umem;
845 	struct i40e_tx_buffer *tx_bi;
846 	u32 xsk_frames = 0;
847 
848 	while (ntc != ntu) {
849 		tx_bi = &tx_ring->tx_bi[ntc];
850 
851 		if (tx_bi->xdpf)
852 			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
853 		else
854 			xsk_frames++;
855 
856 		tx_bi->xdpf = NULL;
857 
858 		ntc++;
859 		if (ntc >= tx_ring->count)
860 			ntc = 0;
861 	}
862 
863 	if (xsk_frames)
864 		xsk_umem_complete_tx(umem, xsk_frames);
865 }
866 
867 /**
868  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
869  * @vsi: vsi
870  *
871  * Returns true if any of the Rx rings has an AF_XDP UMEM attached
872  **/
873 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
874 {
875 	struct net_device *netdev = vsi->netdev;
876 	int i;
877 
878 	for (i = 0; i < vsi->num_queue_pairs; i++) {
879 		if (xdp_get_umem_from_qid(netdev, i))
880 			return true;
881 	}
882 
883 	return false;
884 }
885