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_drv.h>
6#include "i40e_txrx_common.h"
7#include "i40e_xsk.h"
8
9void i40e_clear_rx_bi_zc(struct i40e_ring *rx_ring)
10{
11 memset(rx_ring->rx_bi_zc, 0,
12 sizeof(*rx_ring->rx_bi_zc) * rx_ring->count);
13}
14
15static struct xdp_buff **i40e_rx_bi(struct i40e_ring *rx_ring, u32 idx)
16{
17 return &rx_ring->rx_bi_zc[idx];
18}
19
20/**
21 * i40e_realloc_rx_xdp_bi - reallocate SW ring for either XSK or normal buffer
22 * @rx_ring: Current rx ring
23 * @pool_present: is pool for XSK present
24 *
25 * Try allocating memory and return ENOMEM, if failed to allocate.
26 * If allocation was successful, substitute buffer with allocated one.
27 * Returns 0 on success, negative on failure
28 */
29static int i40e_realloc_rx_xdp_bi(struct i40e_ring *rx_ring, bool pool_present)
30{
31 size_t elem_size = pool_present ? sizeof(*rx_ring->rx_bi_zc) :
32 sizeof(*rx_ring->rx_bi);
33 void *sw_ring = kcalloc(n: rx_ring->count, size: elem_size, GFP_KERNEL);
34
35 if (!sw_ring)
36 return -ENOMEM;
37
38 if (pool_present) {
39 kfree(objp: rx_ring->rx_bi);
40 rx_ring->rx_bi = NULL;
41 rx_ring->rx_bi_zc = sw_ring;
42 } else {
43 kfree(objp: rx_ring->rx_bi_zc);
44 rx_ring->rx_bi_zc = NULL;
45 rx_ring->rx_bi = sw_ring;
46 }
47 return 0;
48}
49
50/**
51 * i40e_realloc_rx_bi_zc - reallocate rx SW rings
52 * @vsi: Current VSI
53 * @zc: is zero copy set
54 *
55 * Reallocate buffer for rx_rings that might be used by XSK.
56 * XDP requires more memory, than rx_buf provides.
57 * Returns 0 on success, negative on failure
58 */
59int i40e_realloc_rx_bi_zc(struct i40e_vsi *vsi, bool zc)
60{
61 struct i40e_ring *rx_ring;
62 unsigned long q;
63
64 for_each_set_bit(q, vsi->af_xdp_zc_qps, vsi->alloc_queue_pairs) {
65 rx_ring = vsi->rx_rings[q];
66 if (i40e_realloc_rx_xdp_bi(rx_ring, pool_present: zc))
67 return -ENOMEM;
68 }
69 return 0;
70}
71
72/**
73 * i40e_xsk_pool_enable - Enable/associate an AF_XDP buffer pool to a
74 * certain ring/qid
75 * @vsi: Current VSI
76 * @pool: buffer pool
77 * @qid: Rx ring to associate buffer pool with
78 *
79 * Returns 0 on success, <0 on failure
80 **/
81static int i40e_xsk_pool_enable(struct i40e_vsi *vsi,
82 struct xsk_buff_pool *pool,
83 u16 qid)
84{
85 struct net_device *netdev = vsi->netdev;
86 bool if_running;
87 int err;
88
89 if (vsi->type != I40E_VSI_MAIN)
90 return -EINVAL;
91
92 if (qid >= vsi->num_queue_pairs)
93 return -EINVAL;
94
95 if (qid >= netdev->real_num_rx_queues ||
96 qid >= netdev->real_num_tx_queues)
97 return -EINVAL;
98
99 err = xsk_pool_dma_map(pool, dev: &vsi->back->pdev->dev, I40E_RX_DMA_ATTR);
100 if (err)
101 return err;
102
103 set_bit(nr: qid, addr: vsi->af_xdp_zc_qps);
104
105 if_running = netif_running(dev: vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
106
107 if (if_running) {
108 err = i40e_queue_pair_disable(vsi, queue_pair: qid);
109 if (err)
110 return err;
111
112 err = i40e_realloc_rx_xdp_bi(rx_ring: vsi->rx_rings[qid], pool_present: true);
113 if (err)
114 return err;
115
116 err = i40e_queue_pair_enable(vsi, queue_pair: qid);
117 if (err)
118 return err;
119
120 /* Kick start the NAPI context so that receiving will start */
121 err = i40e_xsk_wakeup(dev: vsi->netdev, queue_id: qid, XDP_WAKEUP_RX);
122 if (err)
123 return err;
124 }
125
126 return 0;
127}
128
129/**
130 * i40e_xsk_pool_disable - Disassociate an AF_XDP buffer pool from a
131 * certain ring/qid
132 * @vsi: Current VSI
133 * @qid: Rx ring to associate buffer pool with
134 *
135 * Returns 0 on success, <0 on failure
136 **/
137static int i40e_xsk_pool_disable(struct i40e_vsi *vsi, u16 qid)
138{
139 struct net_device *netdev = vsi->netdev;
140 struct xsk_buff_pool *pool;
141 bool if_running;
142 int err;
143
144 pool = xsk_get_pool_from_qid(dev: netdev, queue_id: qid);
145 if (!pool)
146 return -EINVAL;
147
148 if_running = netif_running(dev: vsi->netdev) && i40e_enabled_xdp_vsi(vsi);
149
150 if (if_running) {
151 err = i40e_queue_pair_disable(vsi, queue_pair: qid);
152 if (err)
153 return err;
154 }
155
156 clear_bit(nr: qid, addr: vsi->af_xdp_zc_qps);
157 xsk_pool_dma_unmap(pool, I40E_RX_DMA_ATTR);
158
159 if (if_running) {
160 err = i40e_realloc_rx_xdp_bi(rx_ring: vsi->rx_rings[qid], pool_present: false);
161 if (err)
162 return err;
163 err = i40e_queue_pair_enable(vsi, queue_pair: qid);
164 if (err)
165 return err;
166 }
167
168 return 0;
169}
170
171/**
172 * i40e_xsk_pool_setup - Enable/disassociate an AF_XDP buffer pool to/from
173 * a ring/qid
174 * @vsi: Current VSI
175 * @pool: Buffer pool to enable/associate to a ring, or NULL to disable
176 * @qid: Rx ring to (dis)associate buffer pool (from)to
177 *
178 * This function enables or disables a buffer pool to a certain ring.
179 *
180 * Returns 0 on success, <0 on failure
181 **/
182int i40e_xsk_pool_setup(struct i40e_vsi *vsi, struct xsk_buff_pool *pool,
183 u16 qid)
184{
185 return pool ? i40e_xsk_pool_enable(vsi, pool, qid) :
186 i40e_xsk_pool_disable(vsi, qid);
187}
188
189/**
190 * i40e_run_xdp_zc - Executes an XDP program on an xdp_buff
191 * @rx_ring: Rx ring
192 * @xdp: xdp_buff used as input to the XDP program
193 * @xdp_prog: XDP program to run
194 *
195 * Returns any of I40E_XDP_{PASS, CONSUMED, TX, REDIR}
196 **/
197static int i40e_run_xdp_zc(struct i40e_ring *rx_ring, struct xdp_buff *xdp,
198 struct bpf_prog *xdp_prog)
199{
200 int err, result = I40E_XDP_PASS;
201 struct i40e_ring *xdp_ring;
202 u32 act;
203
204 act = bpf_prog_run_xdp(prog: xdp_prog, xdp);
205
206 if (likely(act == XDP_REDIRECT)) {
207 err = xdp_do_redirect(dev: rx_ring->netdev, xdp, prog: xdp_prog);
208 if (!err)
209 return I40E_XDP_REDIR;
210 if (xsk_uses_need_wakeup(pool: rx_ring->xsk_pool) && err == -ENOBUFS)
211 result = I40E_XDP_EXIT;
212 else
213 result = I40E_XDP_CONSUMED;
214 goto out_failure;
215 }
216
217 switch (act) {
218 case XDP_PASS:
219 break;
220 case XDP_TX:
221 xdp_ring = rx_ring->vsi->xdp_rings[rx_ring->queue_index];
222 result = i40e_xmit_xdp_tx_ring(xdp, xdp_ring);
223 if (result == I40E_XDP_CONSUMED)
224 goto out_failure;
225 break;
226 case XDP_DROP:
227 result = I40E_XDP_CONSUMED;
228 break;
229 default:
230 bpf_warn_invalid_xdp_action(dev: rx_ring->netdev, prog: xdp_prog, act);
231 fallthrough;
232 case XDP_ABORTED:
233 result = I40E_XDP_CONSUMED;
234out_failure:
235 trace_xdp_exception(dev: rx_ring->netdev, xdp: xdp_prog, act);
236 }
237 return result;
238}
239
240bool i40e_alloc_rx_buffers_zc(struct i40e_ring *rx_ring, u16 count)
241{
242 u16 ntu = rx_ring->next_to_use;
243 union i40e_rx_desc *rx_desc;
244 struct xdp_buff **xdp;
245 u32 nb_buffs, i;
246 dma_addr_t dma;
247
248 rx_desc = I40E_RX_DESC(rx_ring, ntu);
249 xdp = i40e_rx_bi(rx_ring, idx: ntu);
250
251 nb_buffs = min_t(u16, count, rx_ring->count - ntu);
252 nb_buffs = xsk_buff_alloc_batch(pool: rx_ring->xsk_pool, xdp, max: nb_buffs);
253 if (!nb_buffs)
254 return false;
255
256 i = nb_buffs;
257 while (i--) {
258 dma = xsk_buff_xdp_get_dma(xdp: *xdp);
259 rx_desc->read.pkt_addr = cpu_to_le64(dma);
260 rx_desc->read.hdr_addr = 0;
261
262 rx_desc++;
263 xdp++;
264 }
265
266 ntu += nb_buffs;
267 if (ntu == rx_ring->count) {
268 rx_desc = I40E_RX_DESC(rx_ring, 0);
269 ntu = 0;
270 }
271
272 /* clear the status bits for the next_to_use descriptor */
273 rx_desc->wb.qword1.status_error_len = 0;
274 i40e_release_rx_desc(rx_ring, val: ntu);
275
276 return count == nb_buffs;
277}
278
279/**
280 * i40e_construct_skb_zc - Create skbuff from zero-copy Rx buffer
281 * @rx_ring: Rx ring
282 * @xdp: xdp_buff
283 *
284 * This functions allocates a new skb from a zero-copy Rx buffer.
285 *
286 * Returns the skb, or NULL on failure.
287 **/
288static struct sk_buff *i40e_construct_skb_zc(struct i40e_ring *rx_ring,
289 struct xdp_buff *xdp)
290{
291 unsigned int totalsize = xdp->data_end - xdp->data_meta;
292 unsigned int metasize = xdp->data - xdp->data_meta;
293 struct skb_shared_info *sinfo = NULL;
294 struct sk_buff *skb;
295 u32 nr_frags = 0;
296
297 if (unlikely(xdp_buff_has_frags(xdp))) {
298 sinfo = xdp_get_shared_info_from_buff(xdp);
299 nr_frags = sinfo->nr_frags;
300 }
301 net_prefetch(p: xdp->data_meta);
302
303 /* allocate a skb to store the frags */
304 skb = __napi_alloc_skb(napi: &rx_ring->q_vector->napi, length: totalsize,
305 GFP_ATOMIC | __GFP_NOWARN);
306 if (unlikely(!skb))
307 goto out;
308
309 memcpy(__skb_put(skb, totalsize), xdp->data_meta,
310 ALIGN(totalsize, sizeof(long)));
311
312 if (metasize) {
313 skb_metadata_set(skb, meta_len: metasize);
314 __skb_pull(skb, len: metasize);
315 }
316
317 if (likely(!xdp_buff_has_frags(xdp)))
318 goto out;
319
320 for (int i = 0; i < nr_frags; i++) {
321 struct skb_shared_info *skinfo = skb_shinfo(skb);
322 skb_frag_t *frag = &sinfo->frags[i];
323 struct page *page;
324 void *addr;
325
326 page = dev_alloc_page();
327 if (!page) {
328 dev_kfree_skb(skb);
329 return NULL;
330 }
331 addr = page_to_virt(page);
332
333 memcpy(addr, skb_frag_page(frag), skb_frag_size(frag));
334
335 __skb_fill_page_desc_noacc(shinfo: skinfo, i: skinfo->nr_frags++,
336 page: addr, off: 0, size: skb_frag_size(frag));
337 }
338
339out:
340 xsk_buff_free(xdp);
341 return skb;
342}
343
344static void i40e_handle_xdp_result_zc(struct i40e_ring *rx_ring,
345 struct xdp_buff *xdp_buff,
346 union i40e_rx_desc *rx_desc,
347 unsigned int *rx_packets,
348 unsigned int *rx_bytes,
349 unsigned int xdp_res,
350 bool *failure)
351{
352 struct sk_buff *skb;
353
354 *rx_packets = 1;
355 *rx_bytes = xdp_get_buff_len(xdp: xdp_buff);
356
357 if (likely(xdp_res == I40E_XDP_REDIR) || xdp_res == I40E_XDP_TX)
358 return;
359
360 if (xdp_res == I40E_XDP_EXIT) {
361 *failure = true;
362 return;
363 }
364
365 if (xdp_res == I40E_XDP_CONSUMED) {
366 xsk_buff_free(xdp: xdp_buff);
367 return;
368 }
369 if (xdp_res == I40E_XDP_PASS) {
370 /* NB! We are not checking for errors using
371 * i40e_test_staterr with
372 * BIT(I40E_RXD_QW1_ERROR_SHIFT). This is due to that
373 * SBP is *not* set in PRT_SBPVSI (default not set).
374 */
375 skb = i40e_construct_skb_zc(rx_ring, xdp: xdp_buff);
376 if (!skb) {
377 rx_ring->rx_stats.alloc_buff_failed++;
378 *rx_packets = 0;
379 *rx_bytes = 0;
380 return;
381 }
382
383 if (eth_skb_pad(skb)) {
384 *rx_packets = 0;
385 *rx_bytes = 0;
386 return;
387 }
388
389 i40e_process_skb_fields(rx_ring, rx_desc, skb);
390 napi_gro_receive(napi: &rx_ring->q_vector->napi, skb);
391 return;
392 }
393
394 /* Should never get here, as all valid cases have been handled already.
395 */
396 WARN_ON_ONCE(1);
397}
398
399static int
400i40e_add_xsk_frag(struct i40e_ring *rx_ring, struct xdp_buff *first,
401 struct xdp_buff *xdp, const unsigned int size)
402{
403 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp: first);
404
405 if (!xdp_buff_has_frags(xdp: first)) {
406 sinfo->nr_frags = 0;
407 sinfo->xdp_frags_size = 0;
408 xdp_buff_set_frags_flag(xdp: first);
409 }
410
411 if (unlikely(sinfo->nr_frags == MAX_SKB_FRAGS)) {
412 xsk_buff_free(xdp: first);
413 return -ENOMEM;
414 }
415
416 __skb_fill_page_desc_noacc(shinfo: sinfo, i: sinfo->nr_frags++,
417 virt_to_page(xdp->data_hard_start),
418 XDP_PACKET_HEADROOM, size);
419 sinfo->xdp_frags_size += size;
420 xsk_buff_add_frag(xdp);
421
422 return 0;
423}
424
425/**
426 * i40e_clean_rx_irq_zc - Consumes Rx packets from the hardware ring
427 * @rx_ring: Rx ring
428 * @budget: NAPI budget
429 *
430 * Returns amount of work completed
431 **/
432int i40e_clean_rx_irq_zc(struct i40e_ring *rx_ring, int budget)
433{
434 unsigned int total_rx_bytes = 0, total_rx_packets = 0;
435 u16 next_to_process = rx_ring->next_to_process;
436 u16 next_to_clean = rx_ring->next_to_clean;
437 unsigned int xdp_res, xdp_xmit = 0;
438 struct xdp_buff *first = NULL;
439 u32 count = rx_ring->count;
440 struct bpf_prog *xdp_prog;
441 u32 entries_to_alloc;
442 bool failure = false;
443
444 if (next_to_process != next_to_clean)
445 first = *i40e_rx_bi(rx_ring, idx: next_to_clean);
446
447 /* NB! xdp_prog will always be !NULL, due to the fact that
448 * this path is enabled by setting an XDP program.
449 */
450 xdp_prog = READ_ONCE(rx_ring->xdp_prog);
451
452 while (likely(total_rx_packets < (unsigned int)budget)) {
453 union i40e_rx_desc *rx_desc;
454 unsigned int rx_packets;
455 unsigned int rx_bytes;
456 struct xdp_buff *bi;
457 unsigned int size;
458 u64 qword;
459
460 rx_desc = I40E_RX_DESC(rx_ring, next_to_process);
461 qword = le64_to_cpu(rx_desc->wb.qword1.status_error_len);
462
463 /* This memory barrier is needed to keep us from reading
464 * any other fields out of the rx_desc until we have
465 * verified the descriptor has been written back.
466 */
467 dma_rmb();
468
469 if (i40e_rx_is_programming_status(qword1: qword)) {
470 i40e_clean_programming_status(rx_ring,
471 qword0_raw: rx_desc->raw.qword[0],
472 qword1: qword);
473 bi = *i40e_rx_bi(rx_ring, idx: next_to_process);
474 xsk_buff_free(xdp: bi);
475 if (++next_to_process == count)
476 next_to_process = 0;
477 continue;
478 }
479
480 size = FIELD_GET(I40E_RXD_QW1_LENGTH_PBUF_MASK, qword);
481 if (!size)
482 break;
483
484 bi = *i40e_rx_bi(rx_ring, idx: next_to_process);
485 xsk_buff_set_size(xdp: bi, size);
486 xsk_buff_dma_sync_for_cpu(xdp: bi, pool: rx_ring->xsk_pool);
487
488 if (!first)
489 first = bi;
490 else if (i40e_add_xsk_frag(rx_ring, first, xdp: bi, size))
491 break;
492
493 if (++next_to_process == count)
494 next_to_process = 0;
495
496 if (i40e_is_non_eop(rx_ring, rx_desc))
497 continue;
498
499 xdp_res = i40e_run_xdp_zc(rx_ring, xdp: first, xdp_prog);
500 i40e_handle_xdp_result_zc(rx_ring, xdp_buff: first, rx_desc, rx_packets: &rx_packets,
501 rx_bytes: &rx_bytes, xdp_res, failure: &failure);
502 next_to_clean = next_to_process;
503 if (failure)
504 break;
505 total_rx_packets += rx_packets;
506 total_rx_bytes += rx_bytes;
507 xdp_xmit |= xdp_res & (I40E_XDP_TX | I40E_XDP_REDIR);
508 first = NULL;
509 }
510
511 rx_ring->next_to_clean = next_to_clean;
512 rx_ring->next_to_process = next_to_process;
513
514 entries_to_alloc = I40E_DESC_UNUSED(rx_ring);
515 if (entries_to_alloc >= I40E_RX_BUFFER_WRITE)
516 failure |= !i40e_alloc_rx_buffers_zc(rx_ring, count: entries_to_alloc);
517
518 i40e_finalize_xdp_rx(rx_ring, xdp_res: xdp_xmit);
519 i40e_update_rx_stats(rx_ring, total_rx_bytes, total_rx_packets);
520
521 if (xsk_uses_need_wakeup(pool: rx_ring->xsk_pool)) {
522 if (failure || next_to_clean == rx_ring->next_to_use)
523 xsk_set_rx_need_wakeup(pool: rx_ring->xsk_pool);
524 else
525 xsk_clear_rx_need_wakeup(pool: rx_ring->xsk_pool);
526
527 return (int)total_rx_packets;
528 }
529 return failure ? budget : (int)total_rx_packets;
530}
531
532static void i40e_xmit_pkt(struct i40e_ring *xdp_ring, struct xdp_desc *desc,
533 unsigned int *total_bytes)
534{
535 u32 cmd = I40E_TX_DESC_CMD_ICRC | xsk_is_eop_desc(desc);
536 struct i40e_tx_desc *tx_desc;
537 dma_addr_t dma;
538
539 dma = xsk_buff_raw_get_dma(pool: xdp_ring->xsk_pool, addr: desc->addr);
540 xsk_buff_raw_dma_sync_for_device(pool: xdp_ring->xsk_pool, dma, size: desc->len);
541
542 tx_desc = I40E_TX_DESC(xdp_ring, xdp_ring->next_to_use++);
543 tx_desc->buffer_addr = cpu_to_le64(dma);
544 tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd: cmd, td_offset: 0, size: desc->len, td_tag: 0);
545
546 *total_bytes += desc->len;
547}
548
549static void i40e_xmit_pkt_batch(struct i40e_ring *xdp_ring, struct xdp_desc *desc,
550 unsigned int *total_bytes)
551{
552 u16 ntu = xdp_ring->next_to_use;
553 struct i40e_tx_desc *tx_desc;
554 dma_addr_t dma;
555 u32 i;
556
557 loop_unrolled_for(i = 0; i < PKTS_PER_BATCH; i++) {
558 u32 cmd = I40E_TX_DESC_CMD_ICRC | xsk_is_eop_desc(desc: &desc[i]);
559
560 dma = xsk_buff_raw_get_dma(pool: xdp_ring->xsk_pool, addr: desc[i].addr);
561 xsk_buff_raw_dma_sync_for_device(pool: xdp_ring->xsk_pool, dma, size: desc[i].len);
562
563 tx_desc = I40E_TX_DESC(xdp_ring, ntu++);
564 tx_desc->buffer_addr = cpu_to_le64(dma);
565 tx_desc->cmd_type_offset_bsz = build_ctob(td_cmd: cmd, td_offset: 0, size: desc[i].len, td_tag: 0);
566
567 *total_bytes += desc[i].len;
568 }
569
570 xdp_ring->next_to_use = ntu;
571}
572
573static void i40e_fill_tx_hw_ring(struct i40e_ring *xdp_ring, struct xdp_desc *descs, u32 nb_pkts,
574 unsigned int *total_bytes)
575{
576 u32 batched, leftover, i;
577
578 batched = nb_pkts & ~(PKTS_PER_BATCH - 1);
579 leftover = nb_pkts & (PKTS_PER_BATCH - 1);
580 for (i = 0; i < batched; i += PKTS_PER_BATCH)
581 i40e_xmit_pkt_batch(xdp_ring, desc: &descs[i], total_bytes);
582 for (i = batched; i < batched + leftover; i++)
583 i40e_xmit_pkt(xdp_ring, desc: &descs[i], total_bytes);
584}
585
586static void i40e_set_rs_bit(struct i40e_ring *xdp_ring)
587{
588 u16 ntu = xdp_ring->next_to_use ? xdp_ring->next_to_use - 1 : xdp_ring->count - 1;
589 struct i40e_tx_desc *tx_desc;
590
591 tx_desc = I40E_TX_DESC(xdp_ring, ntu);
592 tx_desc->cmd_type_offset_bsz |= cpu_to_le64(I40E_TX_DESC_CMD_RS << I40E_TXD_QW1_CMD_SHIFT);
593}
594
595/**
596 * i40e_xmit_zc - Performs zero-copy Tx AF_XDP
597 * @xdp_ring: XDP Tx ring
598 * @budget: NAPI budget
599 *
600 * Returns true if the work is finished.
601 **/
602static bool i40e_xmit_zc(struct i40e_ring *xdp_ring, unsigned int budget)
603{
604 struct xdp_desc *descs = xdp_ring->xsk_pool->tx_descs;
605 u32 nb_pkts, nb_processed = 0;
606 unsigned int total_bytes = 0;
607
608 nb_pkts = xsk_tx_peek_release_desc_batch(pool: xdp_ring->xsk_pool, max: budget);
609 if (!nb_pkts)
610 return true;
611
612 if (xdp_ring->next_to_use + nb_pkts >= xdp_ring->count) {
613 nb_processed = xdp_ring->count - xdp_ring->next_to_use;
614 i40e_fill_tx_hw_ring(xdp_ring, descs, nb_pkts: nb_processed, total_bytes: &total_bytes);
615 xdp_ring->next_to_use = 0;
616 }
617
618 i40e_fill_tx_hw_ring(xdp_ring, descs: &descs[nb_processed], nb_pkts: nb_pkts - nb_processed,
619 total_bytes: &total_bytes);
620
621 /* Request an interrupt for the last frame and bump tail ptr. */
622 i40e_set_rs_bit(xdp_ring);
623 i40e_xdp_ring_update_tail(xdp_ring);
624
625 i40e_update_tx_stats(tx_ring: xdp_ring, total_packets: nb_pkts, total_bytes);
626
627 return nb_pkts < budget;
628}
629
630/**
631 * i40e_clean_xdp_tx_buffer - Frees and unmaps an XDP Tx entry
632 * @tx_ring: XDP Tx ring
633 * @tx_bi: Tx buffer info to clean
634 **/
635static void i40e_clean_xdp_tx_buffer(struct i40e_ring *tx_ring,
636 struct i40e_tx_buffer *tx_bi)
637{
638 xdp_return_frame(xdpf: tx_bi->xdpf);
639 tx_ring->xdp_tx_active--;
640 dma_unmap_single(tx_ring->dev,
641 dma_unmap_addr(tx_bi, dma),
642 dma_unmap_len(tx_bi, len), DMA_TO_DEVICE);
643 dma_unmap_len_set(tx_bi, len, 0);
644}
645
646/**
647 * i40e_clean_xdp_tx_irq - Completes AF_XDP entries, and cleans XDP entries
648 * @vsi: Current VSI
649 * @tx_ring: XDP Tx ring
650 *
651 * Returns true if cleanup/transmission is done.
652 **/
653bool i40e_clean_xdp_tx_irq(struct i40e_vsi *vsi, struct i40e_ring *tx_ring)
654{
655 struct xsk_buff_pool *bp = tx_ring->xsk_pool;
656 u32 i, completed_frames, xsk_frames = 0;
657 u32 head_idx = i40e_get_head(tx_ring);
658 struct i40e_tx_buffer *tx_bi;
659 unsigned int ntc;
660
661 if (head_idx < tx_ring->next_to_clean)
662 head_idx += tx_ring->count;
663 completed_frames = head_idx - tx_ring->next_to_clean;
664
665 if (completed_frames == 0)
666 goto out_xmit;
667
668 if (likely(!tx_ring->xdp_tx_active)) {
669 xsk_frames = completed_frames;
670 goto skip;
671 }
672
673 ntc = tx_ring->next_to_clean;
674
675 for (i = 0; i < completed_frames; i++) {
676 tx_bi = &tx_ring->tx_bi[ntc];
677
678 if (tx_bi->xdpf) {
679 i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
680 tx_bi->xdpf = NULL;
681 } else {
682 xsk_frames++;
683 }
684
685 if (++ntc >= tx_ring->count)
686 ntc = 0;
687 }
688
689skip:
690 tx_ring->next_to_clean += completed_frames;
691 if (unlikely(tx_ring->next_to_clean >= tx_ring->count))
692 tx_ring->next_to_clean -= tx_ring->count;
693
694 if (xsk_frames)
695 xsk_tx_completed(pool: bp, nb_entries: xsk_frames);
696
697 i40e_arm_wb(tx_ring, vsi, budget: completed_frames);
698
699out_xmit:
700 if (xsk_uses_need_wakeup(pool: tx_ring->xsk_pool))
701 xsk_set_tx_need_wakeup(pool: tx_ring->xsk_pool);
702
703 return i40e_xmit_zc(xdp_ring: tx_ring, I40E_DESC_UNUSED(tx_ring));
704}
705
706/**
707 * i40e_xsk_wakeup - Implements the ndo_xsk_wakeup
708 * @dev: the netdevice
709 * @queue_id: queue id to wake up
710 * @flags: ignored in our case since we have Rx and Tx in the same NAPI.
711 *
712 * Returns <0 for errors, 0 otherwise.
713 **/
714int i40e_xsk_wakeup(struct net_device *dev, u32 queue_id, u32 flags)
715{
716 struct i40e_netdev_priv *np = netdev_priv(dev);
717 struct i40e_vsi *vsi = np->vsi;
718 struct i40e_pf *pf = vsi->back;
719 struct i40e_ring *ring;
720
721 if (test_bit(__I40E_CONFIG_BUSY, pf->state))
722 return -EAGAIN;
723
724 if (test_bit(__I40E_VSI_DOWN, vsi->state))
725 return -ENETDOWN;
726
727 if (!i40e_enabled_xdp_vsi(vsi))
728 return -EINVAL;
729
730 if (queue_id >= vsi->num_queue_pairs)
731 return -EINVAL;
732
733 if (!vsi->xdp_rings[queue_id]->xsk_pool)
734 return -EINVAL;
735
736 ring = vsi->xdp_rings[queue_id];
737
738 /* The idea here is that if NAPI is running, mark a miss, so
739 * it will run again. If not, trigger an interrupt and
740 * schedule the NAPI from interrupt context. If NAPI would be
741 * scheduled here, the interrupt affinity would not be
742 * honored.
743 */
744 if (!napi_if_scheduled_mark_missed(n: &ring->q_vector->napi))
745 i40e_force_wb(vsi, q_vector: ring->q_vector);
746
747 return 0;
748}
749
750void i40e_xsk_clean_rx_ring(struct i40e_ring *rx_ring)
751{
752 u16 ntc = rx_ring->next_to_clean;
753 u16 ntu = rx_ring->next_to_use;
754
755 while (ntc != ntu) {
756 struct xdp_buff *rx_bi = *i40e_rx_bi(rx_ring, idx: ntc);
757
758 xsk_buff_free(xdp: rx_bi);
759 ntc++;
760 if (ntc >= rx_ring->count)
761 ntc = 0;
762 }
763}
764
765/**
766 * i40e_xsk_clean_tx_ring - Clean the XDP Tx ring on shutdown
767 * @tx_ring: XDP Tx ring
768 **/
769void i40e_xsk_clean_tx_ring(struct i40e_ring *tx_ring)
770{
771 u16 ntc = tx_ring->next_to_clean, ntu = tx_ring->next_to_use;
772 struct xsk_buff_pool *bp = tx_ring->xsk_pool;
773 struct i40e_tx_buffer *tx_bi;
774 u32 xsk_frames = 0;
775
776 while (ntc != ntu) {
777 tx_bi = &tx_ring->tx_bi[ntc];
778
779 if (tx_bi->xdpf)
780 i40e_clean_xdp_tx_buffer(tx_ring, tx_bi);
781 else
782 xsk_frames++;
783
784 tx_bi->xdpf = NULL;
785
786 ntc++;
787 if (ntc >= tx_ring->count)
788 ntc = 0;
789 }
790
791 if (xsk_frames)
792 xsk_tx_completed(pool: bp, nb_entries: xsk_frames);
793}
794
795/**
796 * i40e_xsk_any_rx_ring_enabled - Checks if Rx rings have an AF_XDP
797 * buffer pool attached
798 * @vsi: vsi
799 *
800 * Returns true if any of the Rx rings has an AF_XDP buffer pool attached
801 **/
802bool i40e_xsk_any_rx_ring_enabled(struct i40e_vsi *vsi)
803{
804 struct net_device *netdev = vsi->netdev;
805 int i;
806
807 for (i = 0; i < vsi->num_queue_pairs; i++) {
808 if (xsk_get_pool_from_qid(dev: netdev, queue_id: i))
809 return true;
810 }
811
812 return false;
813}
814

source code of linux/drivers/net/ethernet/intel/i40e/i40e_xsk.c