xref: /linux/drivers/net/ethernet/intel/i40e/i40e_xsk.c (revision bd628c1bed7902ec1f24ba0fe70758949146abbe)
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_alloc_xsk_umems - Allocate an array to store per ring UMEMs
14  * @vsi: Current VSI
15  *
16  * Returns 0 on success, <0 on failure
17  **/
18 static int i40e_alloc_xsk_umems(struct i40e_vsi *vsi)
19 {
20 	if (vsi->xsk_umems)
21 		return 0;
22 
23 	vsi->num_xsk_umems_used = 0;
24 	vsi->num_xsk_umems = vsi->alloc_queue_pairs;
25 	vsi->xsk_umems = kcalloc(vsi->num_xsk_umems, sizeof(*vsi->xsk_umems),
26 				 GFP_KERNEL);
27 	if (!vsi->xsk_umems) {
28 		vsi->num_xsk_umems = 0;
29 		return -ENOMEM;
30 	}
31 
32 	return 0;
33 }
34 
35 /**
36  * i40e_add_xsk_umem - Store a UMEM for a certain ring/qid
37  * @vsi: Current VSI
38  * @umem: UMEM to store
39  * @qid: Ring/qid to associate with the UMEM
40  *
41  * Returns 0 on success, <0 on failure
42  **/
43 static int i40e_add_xsk_umem(struct i40e_vsi *vsi, struct xdp_umem *umem,
44 			     u16 qid)
45 {
46 	int err;
47 
48 	err = i40e_alloc_xsk_umems(vsi);
49 	if (err)
50 		return err;
51 
52 	vsi->xsk_umems[qid] = umem;
53 	vsi->num_xsk_umems_used++;
54 
55 	return 0;
56 }
57 
58 /**
59  * i40e_remove_xsk_umem - Remove a UMEM for a certain ring/qid
60  * @vsi: Current VSI
61  * @qid: Ring/qid associated with the UMEM
62  **/
63 static void i40e_remove_xsk_umem(struct i40e_vsi *vsi, u16 qid)
64 {
65 	vsi->xsk_umems[qid] = NULL;
66 	vsi->num_xsk_umems_used--;
67 
68 	if (vsi->num_xsk_umems == 0) {
69 		kfree(vsi->xsk_umems);
70 		vsi->xsk_umems = NULL;
71 		vsi->num_xsk_umems = 0;
72 	}
73 }
74 
75 /**
76  * i40e_xsk_umem_dma_map - DMA maps all UMEM memory for the netdev
77  * @vsi: Current VSI
78  * @umem: UMEM to DMA map
79  *
80  * Returns 0 on success, <0 on failure
81  **/
82 static int i40e_xsk_umem_dma_map(struct i40e_vsi *vsi, struct xdp_umem *umem)
83 {
84 	struct i40e_pf *pf = vsi->back;
85 	struct device *dev;
86 	unsigned int i, j;
87 	dma_addr_t dma;
88 
89 	dev = &pf->pdev->dev;
90 	for (i = 0; i < umem->npgs; i++) {
91 		dma = dma_map_page_attrs(dev, umem->pgs[i], 0, PAGE_SIZE,
92 					 DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
93 		if (dma_mapping_error(dev, dma))
94 			goto out_unmap;
95 
96 		umem->pages[i].dma = dma;
97 	}
98 
99 	return 0;
100 
101 out_unmap:
102 	for (j = 0; j < i; j++) {
103 		dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
104 				     DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
105 		umem->pages[i].dma = 0;
106 	}
107 
108 	return -1;
109 }
110 
111 /**
112  * i40e_xsk_umem_dma_unmap - DMA unmaps all UMEM memory for the netdev
113  * @vsi: Current VSI
114  * @umem: UMEM to DMA map
115  **/
116 static void i40e_xsk_umem_dma_unmap(struct i40e_vsi *vsi, struct xdp_umem *umem)
117 {
118 	struct i40e_pf *pf = vsi->back;
119 	struct device *dev;
120 	unsigned int i;
121 
122 	dev = &pf->pdev->dev;
123 
124 	for (i = 0; i < umem->npgs; i++) {
125 		dma_unmap_page_attrs(dev, umem->pages[i].dma, PAGE_SIZE,
126 				     DMA_BIDIRECTIONAL, I40E_RX_DMA_ATTR);
127 
128 		umem->pages[i].dma = 0;
129 	}
130 }
131 
132 /**
133  * i40e_xsk_umem_enable - Enable/associate a UMEM to a certain ring/qid
134  * @vsi: Current VSI
135  * @umem: UMEM
136  * @qid: Rx ring to associate UMEM to
137  *
138  * Returns 0 on success, <0 on failure
139  **/
140 static int i40e_xsk_umem_enable(struct i40e_vsi *vsi, struct xdp_umem *umem,
141 				u16 qid)
142 {
143 	struct xdp_umem_fq_reuse *reuseq;
144 	bool if_running;
145 	int err;
146 
147 	if (vsi->type != I40E_VSI_MAIN)
148 		return -EINVAL;
149 
150 	if (qid >= vsi->num_queue_pairs)
151 		return -EINVAL;
152 
153 	if (vsi->xsk_umems) {
154 		if (qid >= vsi->num_xsk_umems)
155 			return -EINVAL;
156 		if (vsi->xsk_umems[qid])
157 			return -EBUSY;
158 	}
159 
160 	reuseq = xsk_reuseq_prepare(vsi->rx_rings[0]->count);
161 	if (!reuseq)
162 		return -ENOMEM;
163 
164 	xsk_reuseq_free(xsk_reuseq_swap(umem, reuseq));
165 
166 	err = i40e_xsk_umem_dma_map(vsi, umem);
167 	if (err)
168 		return err;
169 
170 	if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
171 
172 	if (if_running) {
173 		err = i40e_queue_pair_disable(vsi, qid);
174 		if (err)
175 			return err;
176 	}
177 
178 	err = i40e_add_xsk_umem(vsi, umem, qid);
179 	if (err)
180 		return err;
181 
182 	if (if_running) {
183 		err = i40e_queue_pair_enable(vsi, qid);
184 		if (err)
185 			return err;
186 	}
187 
188 	return 0;
189 }
190 
191 /**
192  * i40e_xsk_umem_disable - Disassociate a UMEM from a certain ring/qid
193  * @vsi: Current VSI
194  * @qid: Rx ring to associate UMEM to
195  *
196  * Returns 0 on success, <0 on failure
197  **/
198 static int i40e_xsk_umem_disable(struct i40e_vsi *vsi, u16 qid)
199 {
200 	bool if_running;
201 	int err;
202 
203 	if (!vsi->xsk_umems || qid >= vsi->num_xsk_umems ||
204 	    !vsi->xsk_umems[qid])
205 		return -EINVAL;
206 
207 	if_running = netif_running(vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
208 
209 	if (if_running) {
210 		err = i40e_queue_pair_disable(vsi, qid);
211 		if (err)
212 			return err;
213 	}
214 
215 	i40e_xsk_umem_dma_unmap(vsi, vsi->xsk_umems[qid]);
216 	i40e_remove_xsk_umem(vsi, qid);
217 
218 	if (if_running) {
219 		err = i40e_queue_pair_enable(vsi, qid);
220 		if (err)
221 			return err;
222 	}
223 
224 	return 0;
225 }
226 
227 /**
228  * i40e_xsk_umem_query - Queries a certain ring/qid for its UMEM
229  * @vsi: Current VSI
230  * @umem: UMEM associated to the ring, if any
231  * @qid: Rx ring to associate UMEM to
232  *
233  * This function will store, if any, the UMEM associated to certain ring.
234  *
235  * Returns 0 on success, <0 on failure
236  **/
237 int i40e_xsk_umem_query(struct i40e_vsi *vsi, struct xdp_umem **umem,
238 			u16 qid)
239 {
240 	if (vsi->type != I40E_VSI_MAIN)
241 		return -EINVAL;
242 
243 	if (qid >= vsi->num_queue_pairs)
244 		return -EINVAL;
245 
246 	if (vsi->xsk_umems) {
247 		if (qid >= vsi->num_xsk_umems)
248 			return -EINVAL;
249 		*umem = vsi->xsk_umems[qid];
250 		return 0;
251 	}
252 
253 	*umem = NULL;
254 	return 0;
255 }
256 
257 /**
258  * i40e_xsk_umem_setup - Enable/disassociate a UMEM to/from a ring/qid
259  * @vsi: Current VSI
260  * @umem: UMEM to enable/associate to a ring, or NULL to disable
261  * @qid: Rx ring to (dis)associate UMEM (from)to
262  *
263  * This function enables or disables a UMEM to a certain ring.
264  *
265  * Returns 0 on success, <0 on failure
266  **/
267 int i40e_xsk_umem_setup(struct i40e_vsi *vsi, struct xdp_umem *umem,
268 			u16 qid)
269 {
270 	return umem ? i40e_xsk_umem_enable(vsi, umem, qid) :
271 		i40e_xsk_umem_disable(vsi, qid);
272 }
273 
274 /**
275  * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
276  * @rx_ring: Rx ring
277  * @xdp: xdp_buff used as input to the XDP program
278  *
279  * This function enables or disables a UMEM to a certain ring.
280  *
281  * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
282  **/
283 static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp)
284 {
285 	int err, result = I40E_XDP_PASS;
286 	struct i40e_ring *xdp_ring;
287 	struct bpf_prog *xdp_prog;
288 	u32 act;
289 
290 	rcu_read_lock();
291 	/* NB! xdp_prog will always be !NULL, due to the fact that
292 	 * this path is enabled by setting an XDP program.
293 	 */
294 	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
295 	act = bpf_prog_run_xdp(xdp_prog, xdp);
296 	xdp->handle += xdp->data - xdp->data_hard_start;
297 	switch (act) {
298 	case XDP_PASS:
299 		break;
300 	case XDP_TX:
301 		xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
302 		result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
303 		break;
304 	case XDP_REDIRECT:
305 		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
306 		result = !err ? I40E_XDP_REDIR : I40E_XDP_CONSUMED;
307 		break;
308 	default:
309 		bpf_warn_invalid_xdp_action(act);
310 	case XDP_ABORTED:
311 		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
312 		/* fallthrough -- handle aborts by dropping packet */
313 	case XDP_DROP:
314 		result = I40E_XDP_CONSUMED;
315 		break;
316 	}
317 	rcu_read_unlock();
318 	return result;
319 }
320 
321 /**
322  * i40e_alloc_buffer_zc - Allocates an i40e_rx_buffer
323  * @rx_ring: Rx ring
324  * @bi: Rx buffer to populate
325  *
326  * This function allocates an Rx buffer. The buffer can come from fill
327  * queue, or via the recycle queue (next_to_alloc).
328  *
329  * Returns true for a successful allocation, false otherwise
330  **/
331 static bool i40e_alloc_buffer_zc(struct i40e_ring *rx_ring,
332 				 struct i40e_rx_buffer *bi)
333 {
334 	struct xdp_umem *umem = rx_ring->xsk_umem;
335 	void *addr = bi->addr;
336 	u64 handle, hr;
337 
338 	if (addr) {
339 		rx_ring->rx_stats.page_reuse_count++;
340 		return true;
341 	}
342 
343 	if (!xsk_umem_peek_addr(umem, &handle)) {
344 		rx_ring->rx_stats.alloc_page_failed++;
345 		return false;
346 	}
347 
348 	hr = umem->headroom + XDP_PACKET_HEADROOM;
349 
350 	bi->dma = xdp_umem_get_dma(umem, handle);
351 	bi->dma += hr;
352 
353 	bi->addr = xdp_umem_get_data(umem, handle);
354 	bi->addr += hr;
355 
356 	bi->handle = handle + umem->headroom;
357 
358 	xsk_umem_discard_addr(umem);
359 	return true;
360 }
361 
362 /**
363  * i40e_alloc_buffer_slow_zc - Allocates an i40e_rx_buffer
364  * @rx_ring: Rx ring
365  * @bi: Rx buffer to populate
366  *
367  * This function allocates an Rx buffer. The buffer can come from fill
368  * queue, or via the reuse queue.
369  *
370  * Returns true for a successful allocation, false otherwise
371  **/
372 static bool i40e_alloc_buffer_slow_zc(struct i40e_ring *rx_ring,
373 				      struct i40e_rx_buffer *bi)
374 {
375 	struct xdp_umem *umem = rx_ring->xsk_umem;
376 	u64 handle, hr;
377 
378 	if (!xsk_umem_peek_addr_rq(umem, &handle)) {
379 		rx_ring->rx_stats.alloc_page_failed++;
380 		return false;
381 	}
382 
383 	handle &= rx_ring->xsk_umem->chunk_mask;
384 
385 	hr = umem->headroom + XDP_PACKET_HEADROOM;
386 
387 	bi->dma = xdp_umem_get_dma(umem, handle);
388 	bi->dma += hr;
389 
390 	bi->addr = xdp_umem_get_data(umem, handle);
391 	bi->addr += hr;
392 
393 	bi->handle = handle + umem->headroom;
394 
395 	xsk_umem_discard_addr_rq(umem);
396 	return true;
397 }
398 
399 static __always_inline bool
400 __i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count,
401 			   bool alloc(struct i40e_ring *rx_ring,
402 				      struct i40e_rx_buffer *bi))
403 {
404 	u16 ntu = rx_ring->next_to_use;
405 	union i40e_rx_desc *rx_desc;
406 	struct i40e_rx_buffer *bi;
407 	bool ok = true;
408 
409 	rx_desc = I40E_RX_DESC(rx_ring, ntu);
410 	bi = &rx_ring->rx_bi[ntu];
411 	do {
412 		if (!alloc(rx_ring, bi)) {
413 			ok = false;
414 			goto no_buffers;
415 		}
416 
417 		dma_sync_single_range_for_device(rx_ring->dev, bi->dma, 0,
418 						 rx_ring->rx_buf_len,
419 						 DMA_BIDIRECTIONAL);
420 
421 		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma);
422 
423 		rx_desc++;
424 		bi++;
425 		ntu++;
426 
427 		if (unlikely(ntu == rx_ring->count)) {
428 			rx_desc = I40E_RX_DESC(rx_ring, 0);
429 			bi = rx_ring->rx_bi;
430 			ntu = 0;
431 		}
432 
433 		rx_desc->wb.qword1.status_error_len = 0;
434 		count--;
435 	} while (count);
436 
437 no_buffers:
438 	if (rx_ring->next_to_use != ntu)
439 		i40e_release_rx_desc(rx_ring, ntu);
440 
441 	return ok;
442 }
443 
444 /**
445  * i40e_alloc_rx_buffers_zc - Allocates a number of Rx buffers
446  * @rx_ring: Rx ring
447  * @count: The number of buffers to allocate
448  *
449  * This function allocates a number of Rx buffers from the reuse queue
450  * or fill ring and places them on the Rx ring.
451  *
452  * Returns true for a successful allocation, false otherwise
453  **/
454 bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
455 {
456 	return __i40e_alloc_rx_buffers_zc(rx_ring, count,
457 					  i40e_alloc_buffer_slow_zc);
458 }
459 
460 /**
461  * i40e_alloc_rx_buffers_fast_zc - Allocates a number of Rx buffers
462  * @rx_ring: Rx ring
463  * @count: The number of buffers to allocate
464  *
465  * This function allocates a number of Rx buffers from the fill ring
466  * or the internal recycle mechanism and places them on the Rx ring.
467  *
468  * Returns true for a successful allocation, false otherwise
469  **/
470 static bool i40e_alloc_rx_buffers_fast_zc(struct i40e_ring *rx_ring, u16 count)
471 {
472 	return __i40e_alloc_rx_buffers_zc(rx_ring, count,
473 					  i40e_alloc_buffer_zc);
474 }
475 
476 /**
477  * i40e_get_rx_buffer_zc - Return the current Rx buffer
478  * @rx_ring: Rx ring
479  * @size: The size of the rx buffer (read from descriptor)
480  *
481  * This function returns the current, received Rx buffer, and also
482  * does DMA synchronization.  the Rx ring.
483  *
484  * Returns the received Rx buffer
485  **/
486 static struct i40e_rx_buffer *i40e_get_rx_buffer_zc(struct i40e_ring *rx_ring,
487 						    const unsigned int size)
488 {
489 	struct i40e_rx_buffer *bi;
490 
491 	bi = &rx_ring->rx_bi[rx_ring->next_to_clean];
492 
493 	/* we are reusing so sync this buffer for CPU use */
494 	dma_sync_single_range_for_cpu(rx_ring->dev,
495 				      bi->dma, 0,
496 				      size,
497 				      DMA_BIDIRECTIONAL);
498 
499 	return bi;
500 }
501 
502 /**
503  * i40e_reuse_rx_buffer_zc - Recycle an Rx buffer
504  * @rx_ring: Rx ring
505  * @old_bi: The Rx buffer to recycle
506  *
507  * This function recycles a finished Rx buffer, and places it on the
508  * recycle queue (next_to_alloc).
509  **/
510 static void i40e_reuse_rx_buffer_zc(struct i40e_ring *rx_ring,
511 				    struct i40e_rx_buffer *old_bi)
512 {
513 	struct i40e_rx_buffer *new_bi = &rx_ring->rx_bi[rx_ring->next_to_alloc];
514 	unsigned long mask = (unsigned long)rx_ring->xsk_umem->chunk_mask;
515 	u64 hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
516 	u16 nta = rx_ring->next_to_alloc;
517 
518 	/* update, and store next to alloc */
519 	nta++;
520 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
521 
522 	/* transfer page from old buffer to new buffer */
523 	new_bi->dma = old_bi->dma & mask;
524 	new_bi->dma += hr;
525 
526 	new_bi->addr = (void *)((unsigned long)old_bi->addr & mask);
527 	new_bi->addr += hr;
528 
529 	new_bi->handle = old_bi->handle & mask;
530 	new_bi->handle += rx_ring->xsk_umem->headroom;
531 
532 	old_bi->addr = NULL;
533 }
534 
535 /**
536  * i40e_zca_free - Free callback for MEM_TYPE_ZERO_COPY allocations
537  * @alloc: Zero-copy allocator
538  * @handle: Buffer handle
539  **/
540 void i40e_zca_free(struct zero_copy_allocator *alloc, unsigned long handle)
541 {
542 	struct i40e_rx_buffer *bi;
543 	struct i40e_ring *rx_ring;
544 	u64 hr, mask;
545 	u16 nta;
546 
547 	rx_ring = container_of(alloc, struct i40e_ring, zca);
548 	hr = rx_ring->xsk_umem->headroom + XDP_PACKET_HEADROOM;
549 	mask = rx_ring->xsk_umem->chunk_mask;
550 
551 	nta = rx_ring->next_to_alloc;
552 	bi = &rx_ring->rx_bi[nta];
553 
554 	nta++;
555 	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
556 
557 	handle &= mask;
558 
559 	bi->dma = xdp_umem_get_dma(rx_ring->xsk_umem, handle);
560 	bi->dma += hr;
561 
562 	bi->addr = xdp_umem_get_data(rx_ring->xsk_umem, handle);
563 	bi->addr += hr;
564 
565 	bi->handle = (u64)handle + rx_ring->xsk_umem->headroom;
566 }
567 
568 /**
569  * i40e_construct_skb_zc - Create skbufff from zero-copy Rx buffer
570  * @rx_ring: Rx ring
571  * @bi: Rx buffer
572  * @xdp: xdp_buff
573  *
574  * This functions allocates a new skb from a zero-copy Rx buffer.
575  *
576  * Returns the skb, or NULL on failure.
577  **/
578 static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
579 					     struct i40e_rx_buffer *bi,
580 					     struct xdp_buff *xdp)
581 {
582 	unsigned int metasize = xdp->data - xdp->data_meta;
583 	unsigned int datasize = xdp->data_end - xdp->data;
584 	struct sk_buff *skb;
585 
586 	/* allocate a skb to store the frags */
587 	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
588 			       xdp->data_end - xdp->data_hard_start,
589 			       GFP_ATOMIC | __GFP_NOWARN);
590 	if (unlikely(!skb))
591 		return NULL;
592 
593 	skb_reserve(skb, xdp->data - xdp->data_hard_start);
594 	memcpy(__skb_put(skb, datasize), xdp->data, datasize);
595 	if (metasize)
596 		skb_metadata_set(skb, metasize);
597 
598 	i40e_reuse_rx_buffer_zc(rx_ring, bi);
599 	return skb;
600 }
601 
602 /**
603  * i40e_inc_ntc: Advance the next_to_clean index
604  * @rx_ring: Rx ring
605  **/
606 static void i40e_inc_ntc(struct i40e_ring *rx_ring)
607 {
608 	u32 ntc = rx_ring->next_to_clean + 1;
609 
610 	ntc = (ntc < rx_ring->count) ? ntc : 0;
611 	rx_ring->next_to_clean = ntc;
612 	prefetch(I40E_RX_DESC(rx_ring, ntc));
613 }
614 
615 /**
616  * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
617  * @rx_ring: Rx ring
618  * @budget: NAPI budget
619  *
620  * Returns amount of work completed
621  **/
622 int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
623 {
624 	unsigned int total_rx_bytes = 0, total_rx_packets = 0;
625 	u16 cleaned_count = I40E_DESC_UNUSED(rx_ring);
626 	unsigned int xdp_res, xdp_xmit = 0;
627 	bool failure = false;
628 	struct sk_buff *skb;
629 	struct xdp_buff xdp;
630 
631 	xdp.rxq = &rx_ring->xdp_rxq;
632 
633 	while (likely(total_rx_packets < (unsigned int)budget)) {
634 		struct i40e_rx_buffer *bi;
635 		union i40e_rx_desc *rx_desc;
636 		unsigned int size;
637 		u64 qword;
638 
639 		if (cleaned_count >= I40E_RX_BUFFER_WRITE) {
640 			failure = failure ||
641 				  !i40e_alloc_rx_buffers_fast_zc(rx_ring,
642 								 cleaned_count);
643 			cleaned_count = 0;
644 		}
645 
646 		rx_desc = I40E_RX_DESC(rx_ring, rx_ring->next_to_clean);
647 		qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
648 
649 		/* This memory barrier is needed to keep us from reading
650 		 * any other fields out of the rx_desc until we have
651 		 * verified the descriptor has been written back.
652 		 */
653 		dma_rmb();
654 
655 		bi = i40e_clean_programming_status(rx_ring, rx_desc,
656 						   qword);
657 		if (unlikely(bi)) {
658 			i40e_reuse_rx_buffer_zc(rx_ring, bi);
659 			cleaned_count++;
660 			continue;
661 		}
662 
663 		size = (qword & I40E_RXD_QW1_LENGTH_PBUF_MASK) >>
664 		       I40E_RXD_QW1_LENGTH_PBUF_SHIFT;
665 		if (!size)
666 			break;
667 
668 		bi = i40e_get_rx_buffer_zc(rx_ring, size);
669 		xdp.data = bi->addr;
670 		xdp.data_meta = xdp.data;
671 		xdp.data_hard_start = xdp.data - XDP_PACKET_HEADROOM;
672 		xdp.data_end = xdp.data + size;
673 		xdp.handle = bi->handle;
674 
675 		xdp_res = i40e_run_xdp_zc(rx_ring, &xdp);
676 		if (xdp_res) {
677 			if (xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR)) {
678 				xdp_xmit |= xdp_res;
679 				bi->addr = NULL;
680 			} else {
681 				i40e_reuse_rx_buffer_zc(rx_ring, bi);
682 			}
683 
684 			total_rx_bytes += size;
685 			total_rx_packets++;
686 
687 			cleaned_count++;
688 			i40e_inc_ntc(rx_ring);
689 			continue;
690 		}
691 
692 		/* XDP_PASS path */
693 
694 		/* NB! We are not checking for errors using
695 		 * i40e_test_staterr with
696 		 * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
697 		 * SBP is *not* set in PRT_SBPVSI (default not set).
698 		 */
699 		skb = i40e_construct_skb_zc(rx_ring, bi, &xdp);
700 		if (!skb) {
701 			rx_ring->rx_stats.alloc_buff_failed++;
702 			break;
703 		}
704 
705 		cleaned_count++;
706 		i40e_inc_ntc(rx_ring);
707 
708 		if (eth_skb_pad(skb))
709 			continue;
710 
711 		total_rx_bytes += skb->len;
712 		total_rx_packets++;
713 
714 		i40e_process_skb_fields(rx_ring, rx_desc, skb);
715 		napi_gro_receive(&rx_ring->q_vector->napi, skb);
716 	}
717 
718 	i40e_finalize_xdp_rx(rx_ring, xdp_xmit);
719 	i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
720 	return failure ? budget : (int)total_rx_packets;
721 }
722 
723 /**
724  * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
725  * @xdp_ring: XDP Tx ring
726  * @budget: NAPI budget
727  *
728  * Returns true if the work is finished.
729  **/
730 static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
731 {
732 	struct i40e_tx_desc *tx_desc = NULL;
733 	struct i40e_tx_buffer *tx_bi;
734 	bool work_done = true;
735 	dma_addr_t dma;
736 	u32 len;
737 
738 	while (budget-- > 0) {
739 		if (!unlikely(I40E_DESC_UNUSED(xdp_ring))) {
740 			xdp_ring->tx_stats.tx_busy++;
741 			work_done = false;
742 			break;
743 		}
744 
745 		if (!xsk_umem_consume_tx(xdp_ring->xsk_umem, &dma, &len))
746 			break;
747 
748 		dma_sync_single_for_device(xdp_ring->dev, dma, len,
749 					   DMA_BIDIRECTIONAL);
750 
751 		tx_bi = &xdp_ring->tx_bi[xdp_ring->next_to_use];
752 		tx_bi->bytecount = len;
753 
754 		tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use);
755 		tx_desc->buffer_addr = cpu_to_le64(dma);
756 		tx_desc->cmd_type_offset_bsz =
757 			build_ctob(I40E_TX_DESC_CMD_ICRC
758 				   | I40E_TX_DESC_CMD_EOP,
759 				   0, len, 0);
760 
761 		xdp_ring->next_to_use++;
762 		if (xdp_ring->next_to_use == xdp_ring->count)
763 			xdp_ring->next_to_use = 0;
764 	}
765 
766 	if (tx_desc) {
767 		/* Request an interrupt for the last frame and bump tail ptr. */
768 		tx_desc->cmd_type_offset_bsz |= (I40E_TX_DESC_CMD_RS <<
769 						 I40E_TXD_QW1_CMD_SHIFT);
770 		i40e_xdp_ring_update_tail(xdp_ring);
771 
772 		xsk_umem_consume_tx_done(xdp_ring->xsk_umem);
773 	}
774 
775 	return !!budget && work_done;
776 }
777 
778 /**
779  * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
780  * @tx_ring: XDP Tx ring
781  * @tx_bi: Tx buffer info to clean
782  **/
783 static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
784 				     struct i40e_tx_buffer *tx_bi)
785 {
786 	xdp_return_frame(tx_bi->xdpf);
787 	dma_unmap_single(tx_ring->dev,
788 			 dma_unmap_addr(tx_bi, dma),
789 			 dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
790 	dma_unmap_len_set(tx_bi, len, 0);
791 }
792 
793 /**
794  * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
795  * @tx_ring: XDP Tx ring
796  * @tx_bi: Tx buffer info to clean
797  *
798  * Returns true if cleanup/tranmission is done.
799  **/
800 bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi,
801 			   struct i40e_ring *tx_ring, int napi_budget)
802 {
803 	unsigned int ntc, total_bytes = 0, budget = vsi->work_limit;
804 	u32 i, completed_frames, frames_ready, xsk_frames = 0;
805 	struct xdp_umem *umem = tx_ring->xsk_umem;
806 	u32 head_idx = i40e_get_head(tx_ring);
807 	bool work_done = true, xmit_done;
808 	struct i40e_tx_buffer *tx_bi;
809 
810 	if (head_idx < tx_ring->next_to_clean)
811 		head_idx += tx_ring->count;
812 	frames_ready = head_idx - tx_ring->next_to_clean;
813 
814 	if (frames_ready == 0) {
815 		goto out_xmit;
816 	} else if (frames_ready > budget) {
817 		completed_frames = budget;
818 		work_done = false;
819 	} else {
820 		completed_frames = frames_ready;
821 	}
822 
823 	ntc = tx_ring->next_to_clean;
824 
825 	for (i = 0; i < completed_frames; i++) {
826 		tx_bi = &tx_ring->tx_bi[ntc];
827 
828 		if (tx_bi->xdpf)
829 			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
830 		else
831 			xsk_frames++;
832 
833 		tx_bi->xdpf = NULL;
834 		total_bytes += tx_bi->bytecount;
835 
836 		if (++ntc >= tx_ring->count)
837 			ntc = 0;
838 	}
839 
840 	tx_ring->next_to_clean += completed_frames;
841 	if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
842 		tx_ring->next_to_clean -= tx_ring->count;
843 
844 	if (xsk_frames)
845 		xsk_umem_complete_tx(umem, xsk_frames);
846 
847 	i40e_arm_wb(tx_ring, vsi, budget);
848 	i40e_update_tx_stats(tx_ring, completed_frames, total_bytes);
849 
850 out_xmit:
851 	xmit_done = i40e_xmit_zc(tx_ring, budget);
852 
853 	return work_done && xmit_done;
854 }
855 
856 /**
857  * i40e_xsk_async_xmit - Implements the ndo_xsk_async_xmit
858  * @dev: the netdevice
859  * @queue_id: queue id to wake up
860  *
861  * Returns <0 for errors, 0 otherwise.
862  **/
863 int i40e_xsk_async_xmit(struct net_device *dev, u32 queue_id)
864 {
865 	struct i40e_netdev_priv *np = netdev_priv(dev);
866 	struct i40e_vsi *vsi = np->vsi;
867 	struct i40e_ring *ring;
868 
869 	if (test_bit(__I40E_VSI_DOWN, vsi->state))
870 		return -ENETDOWN;
871 
872 	if (!i40e_enabled_xdp_vsi(vsi))
873 		return -ENXIO;
874 
875 	if (queue_id >= vsi->num_queue_pairs)
876 		return -ENXIO;
877 
878 	if (!vsi->xdp_rings[queue_id]->xsk_umem)
879 		return -ENXIO;
880 
881 	ring = vsi->xdp_rings[queue_id];
882 
883 	/* The idea here is that if NAPI is running, mark a miss, so
884 	 * it will run again. If not, trigger an interrupt and
885 	 * schedule the NAPI from interrupt context. If NAPI would be
886 	 * scheduled here, the interrupt affinity would not be
887 	 * honored.
888 	 */
889 	if (!napi_if_scheduled_mark_missed(&ring->q_vector->napi))
890 		i40e_force_wb(vsi, ring->q_vector);
891 
892 	return 0;
893 }
894 
895 void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
896 {
897 	u16 i;
898 
899 	for (i = 0; i < rx_ring->count; i++) {
900 		struct i40e_rx_buffer *rx_bi = &rx_ring->rx_bi[i];
901 
902 		if (!rx_bi->addr)
903 			continue;
904 
905 		xsk_umem_fq_reuse(rx_ring->xsk_umem, rx_bi->handle);
906 		rx_bi->addr = NULL;
907 	}
908 }
909 
910 /**
911  * i40e_xsk_clean_xdp_ring - Clean the XDP Tx ring on shutdown
912  * @xdp_ring: XDP Tx ring
913  **/
914 void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
915 {
916 	u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
917 	struct xdp_umem *umem = tx_ring->xsk_umem;
918 	struct i40e_tx_buffer *tx_bi;
919 	u32 xsk_frames = 0;
920 
921 	while (ntc != ntu) {
922 		tx_bi = &tx_ring->tx_bi[ntc];
923 
924 		if (tx_bi->xdpf)
925 			i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
926 		else
927 			xsk_frames++;
928 
929 		tx_bi->xdpf = NULL;
930 
931 		ntc++;
932 		if (ntc >= tx_ring->count)
933 			ntc = 0;
934 	}
935 
936 	if (xsk_frames)
937 		xsk_umem_complete_tx(umem, xsk_frames);
938 }
939 
940 /**
941  * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have AF_XDP UMEM attached
942  * @vsi: vsi
943  *
944  * Returns true if any of the Rx rings has an AF_XDP UMEM attached
945  **/
946 bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
947 {
948 	int i;
949 
950 	if (!vsi->xsk_umems)
951 		return false;
952 
953 	for (i = 0; i < vsi->num_queue_pairs; i++) {
954 		if (vsi->xsk_umems[i])
955 			return true;
956 	}
957 
958 	return false;
959 }
960