1// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2/* Copyright (C) 2015-2019 Netronome Systems, Inc. */
3
4#include <linux/bpf_trace.h>
5#include <linux/netdevice.h>
6#include <linux/bitfield.h>
7#include <net/xfrm.h>
8
9#include "../nfp_app.h"
10#include "../nfp_net.h"
11#include "../nfp_net_dp.h"
12#include "../nfp_net_xsk.h"
13#include "../crypto/crypto.h"
14#include "../crypto/fw.h"
15#include "nfd3.h"
16
17/* Transmit processing
18 *
19 * One queue controller peripheral queue is used for transmit. The
20 * driver en-queues packets for transmit by advancing the write
21 * pointer. The device indicates that packets have transmitted by
22 * advancing the read pointer. The driver maintains a local copy of
23 * the read and write pointer in @struct nfp_net_tx_ring. The driver
24 * keeps @wr_p in sync with the queue controller write pointer and can
25 * determine how many packets have been transmitted by comparing its
26 * copy of the read pointer @rd_p with the read pointer maintained by
27 * the queue controller peripheral.
28 */
29
30/* Wrappers for deciding when to stop and restart TX queues */
31static int nfp_nfd3_tx_ring_should_wake(struct nfp_net_tx_ring *tx_ring)
32{
33 return !nfp_net_tx_full(tx_ring, MAX_SKB_FRAGS * 4);
34}
35
36static int nfp_nfd3_tx_ring_should_stop(struct nfp_net_tx_ring *tx_ring)
37{
38 return nfp_net_tx_full(tx_ring, MAX_SKB_FRAGS + 1);
39}
40
41/**
42 * nfp_nfd3_tx_ring_stop() - stop tx ring
43 * @nd_q: netdev queue
44 * @tx_ring: driver tx queue structure
45 *
46 * Safely stop TX ring. Remember that while we are running .start_xmit()
47 * someone else may be cleaning the TX ring completions so we need to be
48 * extra careful here.
49 */
50static void
51nfp_nfd3_tx_ring_stop(struct netdev_queue *nd_q,
52 struct nfp_net_tx_ring *tx_ring)
53{
54 netif_tx_stop_queue(dev_queue: nd_q);
55
56 /* We can race with the TX completion out of NAPI so recheck */
57 smp_mb();
58 if (unlikely(nfp_nfd3_tx_ring_should_wake(tx_ring)))
59 netif_tx_start_queue(dev_queue: nd_q);
60}
61
62/**
63 * nfp_nfd3_tx_tso() - Set up Tx descriptor for LSO
64 * @r_vec: per-ring structure
65 * @txbuf: Pointer to driver soft TX descriptor
66 * @txd: Pointer to HW TX descriptor
67 * @skb: Pointer to SKB
68 * @md_bytes: Prepend length
69 *
70 * Set up Tx descriptor for LSO, do nothing for non-LSO skbs.
71 * Return error on packet header greater than maximum supported LSO header size.
72 */
73static void
74nfp_nfd3_tx_tso(struct nfp_net_r_vector *r_vec, struct nfp_nfd3_tx_buf *txbuf,
75 struct nfp_nfd3_tx_desc *txd, struct sk_buff *skb, u32 md_bytes)
76{
77 u32 l3_offset, l4_offset, hdrlen, l4_hdrlen;
78 u16 mss;
79
80 if (!skb_is_gso(skb))
81 return;
82
83 if (!skb->encapsulation) {
84 l3_offset = skb_network_offset(skb);
85 l4_offset = skb_transport_offset(skb);
86 l4_hdrlen = (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ?
87 sizeof(struct udphdr) : tcp_hdrlen(skb);
88 } else {
89 l3_offset = skb_inner_network_offset(skb);
90 l4_offset = skb_inner_transport_offset(skb);
91 l4_hdrlen = (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) ?
92 sizeof(struct udphdr) : inner_tcp_hdrlen(skb);
93 }
94
95 hdrlen = l4_offset + l4_hdrlen;
96 txbuf->pkt_cnt = skb_shinfo(skb)->gso_segs;
97 txbuf->real_len += hdrlen * (txbuf->pkt_cnt - 1);
98
99 mss = skb_shinfo(skb)->gso_size & NFD3_DESC_TX_MSS_MASK;
100 txd->l3_offset = l3_offset - md_bytes;
101 txd->l4_offset = l4_offset - md_bytes;
102 txd->lso_hdrlen = hdrlen - md_bytes;
103 txd->mss = cpu_to_le16(mss);
104 txd->flags |= NFD3_DESC_TX_LSO;
105
106 u64_stats_update_begin(syncp: &r_vec->tx_sync);
107 r_vec->tx_lso++;
108 u64_stats_update_end(syncp: &r_vec->tx_sync);
109}
110
111/**
112 * nfp_nfd3_tx_csum() - Set TX CSUM offload flags in TX descriptor
113 * @dp: NFP Net data path struct
114 * @r_vec: per-ring structure
115 * @txbuf: Pointer to driver soft TX descriptor
116 * @txd: Pointer to TX descriptor
117 * @skb: Pointer to SKB
118 *
119 * This function sets the TX checksum flags in the TX descriptor based
120 * on the configuration and the protocol of the packet to be transmitted.
121 */
122static void
123nfp_nfd3_tx_csum(struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
124 struct nfp_nfd3_tx_buf *txbuf, struct nfp_nfd3_tx_desc *txd,
125 struct sk_buff *skb)
126{
127 struct ipv6hdr *ipv6h;
128 struct iphdr *iph;
129 u8 l4_hdr;
130
131 if (!(dp->ctrl & NFP_NET_CFG_CTRL_TXCSUM))
132 return;
133
134 if (skb->ip_summed != CHECKSUM_PARTIAL)
135 return;
136
137 txd->flags |= NFD3_DESC_TX_CSUM;
138 if (skb->encapsulation)
139 txd->flags |= NFD3_DESC_TX_ENCAP;
140
141 iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
142 ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
143
144 if (iph->version == 4) {
145 txd->flags |= NFD3_DESC_TX_IP4_CSUM;
146 l4_hdr = iph->protocol;
147 } else if (ipv6h->version == 6) {
148 l4_hdr = ipv6h->nexthdr;
149 } else {
150 nn_dp_warn(dp, "partial checksum but ipv=%x!\n", iph->version);
151 return;
152 }
153
154 switch (l4_hdr) {
155 case IPPROTO_TCP:
156 txd->flags |= NFD3_DESC_TX_TCP_CSUM;
157 break;
158 case IPPROTO_UDP:
159 txd->flags |= NFD3_DESC_TX_UDP_CSUM;
160 break;
161 default:
162 nn_dp_warn(dp, "partial checksum but l4 proto=%x!\n", l4_hdr);
163 return;
164 }
165
166 u64_stats_update_begin(syncp: &r_vec->tx_sync);
167 if (skb->encapsulation)
168 r_vec->hw_csum_tx_inner += txbuf->pkt_cnt;
169 else
170 r_vec->hw_csum_tx += txbuf->pkt_cnt;
171 u64_stats_update_end(syncp: &r_vec->tx_sync);
172}
173
174static int nfp_nfd3_prep_tx_meta(struct nfp_net_dp *dp, struct sk_buff *skb,
175 u64 tls_handle, bool *ipsec)
176{
177 struct metadata_dst *md_dst = skb_metadata_dst(skb);
178 struct nfp_ipsec_offload offload_info;
179 unsigned char *data;
180 bool vlan_insert;
181 u32 meta_id = 0;
182 int md_bytes;
183
184#ifdef CONFIG_NFP_NET_IPSEC
185 if (xfrm_offload(skb))
186 *ipsec = nfp_net_ipsec_tx_prep(dp, skb, offload_info: &offload_info);
187#endif
188
189 if (unlikely(md_dst && md_dst->type != METADATA_HW_PORT_MUX))
190 md_dst = NULL;
191
192 vlan_insert = skb_vlan_tag_present(skb) && (dp->ctrl & NFP_NET_CFG_CTRL_TXVLAN_V2);
193
194 if (!(md_dst || tls_handle || vlan_insert || *ipsec))
195 return 0;
196
197 md_bytes = sizeof(meta_id) +
198 (!!md_dst ? NFP_NET_META_PORTID_SIZE : 0) +
199 (!!tls_handle ? NFP_NET_META_CONN_HANDLE_SIZE : 0) +
200 (vlan_insert ? NFP_NET_META_VLAN_SIZE : 0) +
201 (*ipsec ? NFP_NET_META_IPSEC_FIELD_SIZE : 0);
202
203 if (unlikely(skb_cow_head(skb, md_bytes)))
204 return -ENOMEM;
205
206 data = skb_push(skb, len: md_bytes) + md_bytes;
207 if (md_dst) {
208 data -= NFP_NET_META_PORTID_SIZE;
209 put_unaligned_be32(val: md_dst->u.port_info.port_id, p: data);
210 meta_id = NFP_NET_META_PORTID;
211 }
212 if (tls_handle) {
213 /* conn handle is opaque, we just use u64 to be able to quickly
214 * compare it to zero
215 */
216 data -= NFP_NET_META_CONN_HANDLE_SIZE;
217 memcpy(data, &tls_handle, sizeof(tls_handle));
218 meta_id <<= NFP_NET_META_FIELD_SIZE;
219 meta_id |= NFP_NET_META_CONN_HANDLE;
220 }
221 if (vlan_insert) {
222 data -= NFP_NET_META_VLAN_SIZE;
223 /* data type of skb->vlan_proto is __be16
224 * so it fills metadata without calling put_unaligned_be16
225 */
226 memcpy(data, &skb->vlan_proto, sizeof(skb->vlan_proto));
227 put_unaligned_be16(skb_vlan_tag_get(skb), p: data + sizeof(skb->vlan_proto));
228 meta_id <<= NFP_NET_META_FIELD_SIZE;
229 meta_id |= NFP_NET_META_VLAN;
230 }
231 if (*ipsec) {
232 data -= NFP_NET_META_IPSEC_SIZE;
233 put_unaligned_be32(val: offload_info.seq_hi, p: data);
234 data -= NFP_NET_META_IPSEC_SIZE;
235 put_unaligned_be32(val: offload_info.seq_low, p: data);
236 data -= NFP_NET_META_IPSEC_SIZE;
237 put_unaligned_be32(val: offload_info.handle - 1, p: data);
238 meta_id <<= NFP_NET_META_IPSEC_FIELD_SIZE;
239 meta_id |= NFP_NET_META_IPSEC << 8 | NFP_NET_META_IPSEC << 4 | NFP_NET_META_IPSEC;
240 }
241
242 data -= sizeof(meta_id);
243 put_unaligned_be32(val: meta_id, p: data);
244
245 return md_bytes;
246}
247
248/**
249 * nfp_nfd3_tx() - Main transmit entry point
250 * @skb: SKB to transmit
251 * @netdev: netdev structure
252 *
253 * Return: NETDEV_TX_OK on success.
254 */
255netdev_tx_t nfp_nfd3_tx(struct sk_buff *skb, struct net_device *netdev)
256{
257 struct nfp_net *nn = netdev_priv(dev: netdev);
258 int f, nr_frags, wr_idx, md_bytes;
259 struct nfp_net_tx_ring *tx_ring;
260 struct nfp_net_r_vector *r_vec;
261 struct nfp_nfd3_tx_buf *txbuf;
262 struct nfp_nfd3_tx_desc *txd;
263 struct netdev_queue *nd_q;
264 const skb_frag_t *frag;
265 struct nfp_net_dp *dp;
266 dma_addr_t dma_addr;
267 unsigned int fsize;
268 u64 tls_handle = 0;
269 bool ipsec = false;
270 u16 qidx;
271
272 dp = &nn->dp;
273 qidx = skb_get_queue_mapping(skb);
274 tx_ring = &dp->tx_rings[qidx];
275 r_vec = tx_ring->r_vec;
276
277 nr_frags = skb_shinfo(skb)->nr_frags;
278
279 if (unlikely(nfp_net_tx_full(tx_ring, nr_frags + 1))) {
280 nn_dp_warn(dp, "TX ring %d busy. wrp=%u rdp=%u\n",
281 qidx, tx_ring->wr_p, tx_ring->rd_p);
282 nd_q = netdev_get_tx_queue(dev: dp->netdev, index: qidx);
283 netif_tx_stop_queue(dev_queue: nd_q);
284 nfp_net_tx_xmit_more_flush(tx_ring);
285 u64_stats_update_begin(syncp: &r_vec->tx_sync);
286 r_vec->tx_busy++;
287 u64_stats_update_end(syncp: &r_vec->tx_sync);
288 return NETDEV_TX_BUSY;
289 }
290
291 skb = nfp_net_tls_tx(dp, r_vec, skb, tls_handle: &tls_handle, nr_frags: &nr_frags);
292 if (unlikely(!skb)) {
293 nfp_net_tx_xmit_more_flush(tx_ring);
294 return NETDEV_TX_OK;
295 }
296
297 md_bytes = nfp_nfd3_prep_tx_meta(dp, skb, tls_handle, ipsec: &ipsec);
298 if (unlikely(md_bytes < 0))
299 goto err_flush;
300
301 /* Start with the head skbuf */
302 dma_addr = dma_map_single(dp->dev, skb->data, skb_headlen(skb),
303 DMA_TO_DEVICE);
304 if (dma_mapping_error(dev: dp->dev, dma_addr))
305 goto err_dma_err;
306
307 wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
308
309 /* Stash the soft descriptor of the head then initialize it */
310 txbuf = &tx_ring->txbufs[wr_idx];
311 txbuf->skb = skb;
312 txbuf->dma_addr = dma_addr;
313 txbuf->fidx = -1;
314 txbuf->pkt_cnt = 1;
315 txbuf->real_len = skb->len;
316
317 /* Build TX descriptor */
318 txd = &tx_ring->txds[wr_idx];
319 txd->offset_eop = (nr_frags ? 0 : NFD3_DESC_TX_EOP) | md_bytes;
320 txd->dma_len = cpu_to_le16(skb_headlen(skb));
321 nfp_desc_set_dma_addr_40b(txd, dma_addr);
322 txd->data_len = cpu_to_le16(skb->len);
323
324 txd->flags = 0;
325 txd->mss = 0;
326 txd->lso_hdrlen = 0;
327
328 /* Do not reorder - tso may adjust pkt cnt, vlan may override fields */
329 nfp_nfd3_tx_tso(r_vec, txbuf, txd, skb, md_bytes);
330 if (ipsec)
331 nfp_nfd3_ipsec_tx(txd, skb);
332 else
333 nfp_nfd3_tx_csum(dp, r_vec, txbuf, txd, skb);
334 if (skb_vlan_tag_present(skb) && dp->ctrl & NFP_NET_CFG_CTRL_TXVLAN) {
335 txd->flags |= NFD3_DESC_TX_VLAN;
336 txd->vlan = cpu_to_le16(skb_vlan_tag_get(skb));
337 }
338
339 /* Gather DMA */
340 if (nr_frags > 0) {
341 __le64 second_half;
342
343 /* all descs must match except for in addr, length and eop */
344 second_half = txd->vals8[1];
345
346 for (f = 0; f < nr_frags; f++) {
347 frag = &skb_shinfo(skb)->frags[f];
348 fsize = skb_frag_size(frag);
349
350 dma_addr = skb_frag_dma_map(dev: dp->dev, frag, offset: 0,
351 size: fsize, dir: DMA_TO_DEVICE);
352 if (dma_mapping_error(dev: dp->dev, dma_addr))
353 goto err_unmap;
354
355 wr_idx = D_IDX(tx_ring, wr_idx + 1);
356 tx_ring->txbufs[wr_idx].skb = skb;
357 tx_ring->txbufs[wr_idx].dma_addr = dma_addr;
358 tx_ring->txbufs[wr_idx].fidx = f;
359
360 txd = &tx_ring->txds[wr_idx];
361 txd->dma_len = cpu_to_le16(fsize);
362 nfp_desc_set_dma_addr_40b(txd, dma_addr);
363 txd->offset_eop = md_bytes |
364 ((f == nr_frags - 1) ? NFD3_DESC_TX_EOP : 0);
365 txd->vals8[1] = second_half;
366 }
367
368 u64_stats_update_begin(syncp: &r_vec->tx_sync);
369 r_vec->tx_gather++;
370 u64_stats_update_end(syncp: &r_vec->tx_sync);
371 }
372
373 skb_tx_timestamp(skb);
374
375 nd_q = netdev_get_tx_queue(dev: dp->netdev, index: tx_ring->idx);
376
377 tx_ring->wr_p += nr_frags + 1;
378 if (nfp_nfd3_tx_ring_should_stop(tx_ring))
379 nfp_nfd3_tx_ring_stop(nd_q, tx_ring);
380
381 tx_ring->wr_ptr_add += nr_frags + 1;
382 if (__netdev_tx_sent_queue(dev_queue: nd_q, bytes: txbuf->real_len, xmit_more: netdev_xmit_more()))
383 nfp_net_tx_xmit_more_flush(tx_ring);
384
385 return NETDEV_TX_OK;
386
387err_unmap:
388 while (--f >= 0) {
389 frag = &skb_shinfo(skb)->frags[f];
390 dma_unmap_page(dp->dev, tx_ring->txbufs[wr_idx].dma_addr,
391 skb_frag_size(frag), DMA_TO_DEVICE);
392 tx_ring->txbufs[wr_idx].skb = NULL;
393 tx_ring->txbufs[wr_idx].dma_addr = 0;
394 tx_ring->txbufs[wr_idx].fidx = -2;
395 wr_idx = wr_idx - 1;
396 if (wr_idx < 0)
397 wr_idx += tx_ring->cnt;
398 }
399 dma_unmap_single(dp->dev, tx_ring->txbufs[wr_idx].dma_addr,
400 skb_headlen(skb), DMA_TO_DEVICE);
401 tx_ring->txbufs[wr_idx].skb = NULL;
402 tx_ring->txbufs[wr_idx].dma_addr = 0;
403 tx_ring->txbufs[wr_idx].fidx = -2;
404err_dma_err:
405 nn_dp_warn(dp, "Failed to map DMA TX buffer\n");
406err_flush:
407 nfp_net_tx_xmit_more_flush(tx_ring);
408 u64_stats_update_begin(syncp: &r_vec->tx_sync);
409 r_vec->tx_errors++;
410 u64_stats_update_end(syncp: &r_vec->tx_sync);
411 nfp_net_tls_tx_undo(skb, tls_handle);
412 dev_kfree_skb_any(skb);
413 return NETDEV_TX_OK;
414}
415
416/**
417 * nfp_nfd3_tx_complete() - Handled completed TX packets
418 * @tx_ring: TX ring structure
419 * @budget: NAPI budget (only used as bool to determine if in NAPI context)
420 */
421void nfp_nfd3_tx_complete(struct nfp_net_tx_ring *tx_ring, int budget)
422{
423 struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
424 struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
425 u32 done_pkts = 0, done_bytes = 0;
426 struct netdev_queue *nd_q;
427 u32 qcp_rd_p;
428 int todo;
429
430 if (tx_ring->wr_p == tx_ring->rd_p)
431 return;
432
433 /* Work out how many descriptors have been transmitted */
434 qcp_rd_p = nfp_net_read_tx_cmpl(tx_ring, dp);
435
436 if (qcp_rd_p == tx_ring->qcp_rd_p)
437 return;
438
439 todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);
440
441 while (todo--) {
442 const skb_frag_t *frag;
443 struct nfp_nfd3_tx_buf *tx_buf;
444 struct sk_buff *skb;
445 int fidx, nr_frags;
446 int idx;
447
448 idx = D_IDX(tx_ring, tx_ring->rd_p++);
449 tx_buf = &tx_ring->txbufs[idx];
450
451 skb = tx_buf->skb;
452 if (!skb)
453 continue;
454
455 nr_frags = skb_shinfo(skb)->nr_frags;
456 fidx = tx_buf->fidx;
457
458 if (fidx == -1) {
459 /* unmap head */
460 dma_unmap_single(dp->dev, tx_buf->dma_addr,
461 skb_headlen(skb), DMA_TO_DEVICE);
462
463 done_pkts += tx_buf->pkt_cnt;
464 done_bytes += tx_buf->real_len;
465 } else {
466 /* unmap fragment */
467 frag = &skb_shinfo(skb)->frags[fidx];
468 dma_unmap_page(dp->dev, tx_buf->dma_addr,
469 skb_frag_size(frag), DMA_TO_DEVICE);
470 }
471
472 /* check for last gather fragment */
473 if (fidx == nr_frags - 1)
474 napi_consume_skb(skb, budget);
475
476 tx_buf->dma_addr = 0;
477 tx_buf->skb = NULL;
478 tx_buf->fidx = -2;
479 }
480
481 tx_ring->qcp_rd_p = qcp_rd_p;
482
483 u64_stats_update_begin(syncp: &r_vec->tx_sync);
484 r_vec->tx_bytes += done_bytes;
485 r_vec->tx_pkts += done_pkts;
486 u64_stats_update_end(syncp: &r_vec->tx_sync);
487
488 if (!dp->netdev)
489 return;
490
491 nd_q = netdev_get_tx_queue(dev: dp->netdev, index: tx_ring->idx);
492 netdev_tx_completed_queue(dev_queue: nd_q, pkts: done_pkts, bytes: done_bytes);
493 if (nfp_nfd3_tx_ring_should_wake(tx_ring)) {
494 /* Make sure TX thread will see updated tx_ring->rd_p */
495 smp_mb();
496
497 if (unlikely(netif_tx_queue_stopped(nd_q)))
498 netif_tx_wake_queue(dev_queue: nd_q);
499 }
500
501 WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
502 "TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
503 tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
504}
505
506static bool nfp_nfd3_xdp_complete(struct nfp_net_tx_ring *tx_ring)
507{
508 struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
509 struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
510 u32 done_pkts = 0, done_bytes = 0;
511 bool done_all;
512 int idx, todo;
513 u32 qcp_rd_p;
514
515 /* Work out how many descriptors have been transmitted */
516 qcp_rd_p = nfp_net_read_tx_cmpl(tx_ring, dp);
517
518 if (qcp_rd_p == tx_ring->qcp_rd_p)
519 return true;
520
521 todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);
522
523 done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
524 todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);
525
526 tx_ring->qcp_rd_p = D_IDX(tx_ring, tx_ring->qcp_rd_p + todo);
527
528 done_pkts = todo;
529 while (todo--) {
530 idx = D_IDX(tx_ring, tx_ring->rd_p);
531 tx_ring->rd_p++;
532
533 done_bytes += tx_ring->txbufs[idx].real_len;
534 }
535
536 u64_stats_update_begin(syncp: &r_vec->tx_sync);
537 r_vec->tx_bytes += done_bytes;
538 r_vec->tx_pkts += done_pkts;
539 u64_stats_update_end(syncp: &r_vec->tx_sync);
540
541 WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
542 "XDP TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
543 tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
544
545 return done_all;
546}
547
548/* Receive processing
549 */
550
551static void *
552nfp_nfd3_napi_alloc_one(struct nfp_net_dp *dp, dma_addr_t *dma_addr)
553{
554 void *frag;
555
556 if (!dp->xdp_prog) {
557 frag = napi_alloc_frag(fragsz: dp->fl_bufsz);
558 if (unlikely(!frag))
559 return NULL;
560 } else {
561 struct page *page;
562
563 page = dev_alloc_page();
564 if (unlikely(!page))
565 return NULL;
566 frag = page_address(page);
567 }
568
569 *dma_addr = nfp_net_dma_map_rx(dp, frag);
570 if (dma_mapping_error(dev: dp->dev, dma_addr: *dma_addr)) {
571 nfp_net_free_frag(frag, xdp: dp->xdp_prog);
572 nn_dp_warn(dp, "Failed to map DMA RX buffer\n");
573 return NULL;
574 }
575
576 return frag;
577}
578
579/**
580 * nfp_nfd3_rx_give_one() - Put mapped skb on the software and hardware rings
581 * @dp: NFP Net data path struct
582 * @rx_ring: RX ring structure
583 * @frag: page fragment buffer
584 * @dma_addr: DMA address of skb mapping
585 */
586static void
587nfp_nfd3_rx_give_one(const struct nfp_net_dp *dp,
588 struct nfp_net_rx_ring *rx_ring,
589 void *frag, dma_addr_t dma_addr)
590{
591 unsigned int wr_idx;
592
593 wr_idx = D_IDX(rx_ring, rx_ring->wr_p);
594
595 nfp_net_dma_sync_dev_rx(dp, dma_addr);
596
597 /* Stash SKB and DMA address away */
598 rx_ring->rxbufs[wr_idx].frag = frag;
599 rx_ring->rxbufs[wr_idx].dma_addr = dma_addr;
600
601 /* Fill freelist descriptor */
602 rx_ring->rxds[wr_idx].fld.reserved = 0;
603 rx_ring->rxds[wr_idx].fld.meta_len_dd = 0;
604 /* DMA address is expanded to 48-bit width in freelist for NFP3800,
605 * so the *_48b macro is used accordingly, it's also OK to fill
606 * a 40-bit address since the top 8 bits are get set to 0.
607 */
608 nfp_desc_set_dma_addr_48b(&rx_ring->rxds[wr_idx].fld,
609 dma_addr + dp->rx_dma_off);
610
611 rx_ring->wr_p++;
612 if (!(rx_ring->wr_p % NFP_NET_FL_BATCH)) {
613 /* Update write pointer of the freelist queue. Make
614 * sure all writes are flushed before telling the hardware.
615 */
616 wmb();
617 nfp_qcp_wr_ptr_add(q: rx_ring->qcp_fl, NFP_NET_FL_BATCH);
618 }
619}
620
621/**
622 * nfp_nfd3_rx_ring_fill_freelist() - Give buffers from the ring to FW
623 * @dp: NFP Net data path struct
624 * @rx_ring: RX ring to fill
625 */
626void nfp_nfd3_rx_ring_fill_freelist(struct nfp_net_dp *dp,
627 struct nfp_net_rx_ring *rx_ring)
628{
629 unsigned int i;
630
631 if (nfp_net_has_xsk_pool_slow(dp, qid: rx_ring->idx))
632 return nfp_net_xsk_rx_ring_fill_freelist(rx_ring);
633
634 for (i = 0; i < rx_ring->cnt - 1; i++)
635 nfp_nfd3_rx_give_one(dp, rx_ring, frag: rx_ring->rxbufs[i].frag,
636 dma_addr: rx_ring->rxbufs[i].dma_addr);
637}
638
639/**
640 * nfp_nfd3_rx_csum_has_errors() - group check if rxd has any csum errors
641 * @flags: RX descriptor flags field in CPU byte order
642 */
643static int nfp_nfd3_rx_csum_has_errors(u16 flags)
644{
645 u16 csum_all_checked, csum_all_ok;
646
647 csum_all_checked = flags & __PCIE_DESC_RX_CSUM_ALL;
648 csum_all_ok = flags & __PCIE_DESC_RX_CSUM_ALL_OK;
649
650 return csum_all_checked != (csum_all_ok << PCIE_DESC_RX_CSUM_OK_SHIFT);
651}
652
653/**
654 * nfp_nfd3_rx_csum() - set SKB checksum field based on RX descriptor flags
655 * @dp: NFP Net data path struct
656 * @r_vec: per-ring structure
657 * @rxd: Pointer to RX descriptor
658 * @meta: Parsed metadata prepend
659 * @skb: Pointer to SKB
660 */
661void
662nfp_nfd3_rx_csum(const struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
663 const struct nfp_net_rx_desc *rxd,
664 const struct nfp_meta_parsed *meta, struct sk_buff *skb)
665{
666 skb_checksum_none_assert(skb);
667
668 if (!(dp->netdev->features & NETIF_F_RXCSUM))
669 return;
670
671 if (meta->csum_type) {
672 skb->ip_summed = meta->csum_type;
673 skb->csum = meta->csum;
674 u64_stats_update_begin(syncp: &r_vec->rx_sync);
675 r_vec->hw_csum_rx_complete++;
676 u64_stats_update_end(syncp: &r_vec->rx_sync);
677 return;
678 }
679
680 if (nfp_nfd3_rx_csum_has_errors(le16_to_cpu(rxd->rxd.flags))) {
681 u64_stats_update_begin(syncp: &r_vec->rx_sync);
682 r_vec->hw_csum_rx_error++;
683 u64_stats_update_end(syncp: &r_vec->rx_sync);
684 return;
685 }
686
687 /* Assume that the firmware will never report inner CSUM_OK unless outer
688 * L4 headers were successfully parsed. FW will always report zero UDP
689 * checksum as CSUM_OK.
690 */
691 if (rxd->rxd.flags & PCIE_DESC_RX_TCP_CSUM_OK ||
692 rxd->rxd.flags & PCIE_DESC_RX_UDP_CSUM_OK) {
693 __skb_incr_checksum_unnecessary(skb);
694 u64_stats_update_begin(syncp: &r_vec->rx_sync);
695 r_vec->hw_csum_rx_ok++;
696 u64_stats_update_end(syncp: &r_vec->rx_sync);
697 }
698
699 if (rxd->rxd.flags & PCIE_DESC_RX_I_TCP_CSUM_OK ||
700 rxd->rxd.flags & PCIE_DESC_RX_I_UDP_CSUM_OK) {
701 __skb_incr_checksum_unnecessary(skb);
702 u64_stats_update_begin(syncp: &r_vec->rx_sync);
703 r_vec->hw_csum_rx_inner_ok++;
704 u64_stats_update_end(syncp: &r_vec->rx_sync);
705 }
706}
707
708static void
709nfp_nfd3_set_hash(struct net_device *netdev, struct nfp_meta_parsed *meta,
710 unsigned int type, __be32 *hash)
711{
712 if (!(netdev->features & NETIF_F_RXHASH))
713 return;
714
715 switch (type) {
716 case NFP_NET_RSS_IPV4:
717 case NFP_NET_RSS_IPV6:
718 case NFP_NET_RSS_IPV6_EX:
719 meta->hash_type = PKT_HASH_TYPE_L3;
720 break;
721 default:
722 meta->hash_type = PKT_HASH_TYPE_L4;
723 break;
724 }
725
726 meta->hash = get_unaligned_be32(p: hash);
727}
728
729static void
730nfp_nfd3_set_hash_desc(struct net_device *netdev, struct nfp_meta_parsed *meta,
731 void *data, struct nfp_net_rx_desc *rxd)
732{
733 struct nfp_net_rx_hash *rx_hash = data;
734
735 if (!(rxd->rxd.flags & PCIE_DESC_RX_RSS))
736 return;
737
738 nfp_nfd3_set_hash(netdev, meta, type: get_unaligned_be32(p: &rx_hash->hash_type),
739 hash: &rx_hash->hash);
740}
741
742bool
743nfp_nfd3_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
744 void *data, void *pkt, unsigned int pkt_len, int meta_len)
745{
746 u32 meta_info, vlan_info;
747
748 meta_info = get_unaligned_be32(p: data);
749 data += 4;
750
751 while (meta_info) {
752 switch (meta_info & NFP_NET_META_FIELD_MASK) {
753 case NFP_NET_META_HASH:
754 meta_info >>= NFP_NET_META_FIELD_SIZE;
755 nfp_nfd3_set_hash(netdev, meta,
756 type: meta_info & NFP_NET_META_FIELD_MASK,
757 hash: (__be32 *)data);
758 data += 4;
759 break;
760 case NFP_NET_META_MARK:
761 meta->mark = get_unaligned_be32(p: data);
762 data += 4;
763 break;
764 case NFP_NET_META_VLAN:
765 vlan_info = get_unaligned_be32(p: data);
766 if (FIELD_GET(NFP_NET_META_VLAN_STRIP, vlan_info)) {
767 meta->vlan.stripped = true;
768 meta->vlan.tpid = FIELD_GET(NFP_NET_META_VLAN_TPID_MASK,
769 vlan_info);
770 meta->vlan.tci = FIELD_GET(NFP_NET_META_VLAN_TCI_MASK,
771 vlan_info);
772 }
773 data += 4;
774 break;
775 case NFP_NET_META_PORTID:
776 meta->portid = get_unaligned_be32(p: data);
777 data += 4;
778 break;
779 case NFP_NET_META_CSUM:
780 meta->csum_type = CHECKSUM_COMPLETE;
781 meta->csum =
782 (__force __wsum)__get_unaligned_cpu32(p: data);
783 data += 4;
784 break;
785 case NFP_NET_META_RESYNC_INFO:
786 if (nfp_net_tls_rx_resync_req(netdev, req: data, pkt,
787 pkt_len))
788 return false;
789 data += sizeof(struct nfp_net_tls_resync_req);
790 break;
791#ifdef CONFIG_NFP_NET_IPSEC
792 case NFP_NET_META_IPSEC:
793 /* Note: IPsec packet will have zero saidx, so need add 1
794 * to indicate packet is IPsec packet within driver.
795 */
796 meta->ipsec_saidx = get_unaligned_be32(p: data) + 1;
797 data += 4;
798 break;
799#endif
800 default:
801 return true;
802 }
803
804 meta_info >>= NFP_NET_META_FIELD_SIZE;
805 }
806
807 return data != pkt;
808}
809
810static void
811nfp_nfd3_rx_drop(const struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
812 struct nfp_net_rx_ring *rx_ring, struct nfp_net_rx_buf *rxbuf,
813 struct sk_buff *skb)
814{
815 u64_stats_update_begin(syncp: &r_vec->rx_sync);
816 r_vec->rx_drops++;
817 /* If we have both skb and rxbuf the replacement buffer allocation
818 * must have failed, count this as an alloc failure.
819 */
820 if (skb && rxbuf)
821 r_vec->rx_replace_buf_alloc_fail++;
822 u64_stats_update_end(syncp: &r_vec->rx_sync);
823
824 /* skb is build based on the frag, free_skb() would free the frag
825 * so to be able to reuse it we need an extra ref.
826 */
827 if (skb && rxbuf && skb->head == rxbuf->frag)
828 page_ref_inc(page: virt_to_head_page(x: rxbuf->frag));
829 if (rxbuf)
830 nfp_nfd3_rx_give_one(dp, rx_ring, frag: rxbuf->frag, dma_addr: rxbuf->dma_addr);
831 if (skb)
832 dev_kfree_skb_any(skb);
833}
834
835static bool
836nfp_nfd3_tx_xdp_buf(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring,
837 struct nfp_net_tx_ring *tx_ring,
838 struct nfp_net_rx_buf *rxbuf, unsigned int dma_off,
839 unsigned int pkt_len, bool *completed)
840{
841 unsigned int dma_map_sz = dp->fl_bufsz - NFP_NET_RX_BUF_NON_DATA;
842 struct nfp_nfd3_tx_buf *txbuf;
843 struct nfp_nfd3_tx_desc *txd;
844 int wr_idx;
845
846 /* Reject if xdp_adjust_tail grow packet beyond DMA area */
847 if (pkt_len + dma_off > dma_map_sz)
848 return false;
849
850 if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
851 if (!*completed) {
852 nfp_nfd3_xdp_complete(tx_ring);
853 *completed = true;
854 }
855
856 if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
857 nfp_nfd3_rx_drop(dp, r_vec: rx_ring->r_vec, rx_ring, rxbuf,
858 NULL);
859 return false;
860 }
861 }
862
863 wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
864
865 /* Stash the soft descriptor of the head then initialize it */
866 txbuf = &tx_ring->txbufs[wr_idx];
867
868 nfp_nfd3_rx_give_one(dp, rx_ring, frag: txbuf->frag, dma_addr: txbuf->dma_addr);
869
870 txbuf->frag = rxbuf->frag;
871 txbuf->dma_addr = rxbuf->dma_addr;
872 txbuf->fidx = -1;
873 txbuf->pkt_cnt = 1;
874 txbuf->real_len = pkt_len;
875
876 dma_sync_single_for_device(dev: dp->dev, addr: rxbuf->dma_addr + dma_off,
877 size: pkt_len, dir: DMA_BIDIRECTIONAL);
878
879 /* Build TX descriptor */
880 txd = &tx_ring->txds[wr_idx];
881 txd->offset_eop = NFD3_DESC_TX_EOP;
882 txd->dma_len = cpu_to_le16(pkt_len);
883 nfp_desc_set_dma_addr_40b(txd, rxbuf->dma_addr + dma_off);
884 txd->data_len = cpu_to_le16(pkt_len);
885
886 txd->flags = 0;
887 txd->mss = 0;
888 txd->lso_hdrlen = 0;
889
890 tx_ring->wr_p++;
891 tx_ring->wr_ptr_add++;
892 return true;
893}
894
895/**
896 * nfp_nfd3_rx() - receive up to @budget packets on @rx_ring
897 * @rx_ring: RX ring to receive from
898 * @budget: NAPI budget
899 *
900 * Note, this function is separated out from the napi poll function to
901 * more cleanly separate packet receive code from other bookkeeping
902 * functions performed in the napi poll function.
903 *
904 * Return: Number of packets received.
905 */
906static int nfp_nfd3_rx(struct nfp_net_rx_ring *rx_ring, int budget)
907{
908 struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
909 struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
910 struct nfp_net_tx_ring *tx_ring;
911 struct bpf_prog *xdp_prog;
912 int idx, pkts_polled = 0;
913 bool xdp_tx_cmpl = false;
914 unsigned int true_bufsz;
915 struct sk_buff *skb;
916 struct xdp_buff xdp;
917
918 xdp_prog = READ_ONCE(dp->xdp_prog);
919 true_bufsz = xdp_prog ? PAGE_SIZE : dp->fl_bufsz;
920 xdp_init_buff(xdp: &xdp, PAGE_SIZE - NFP_NET_RX_BUF_HEADROOM,
921 rxq: &rx_ring->xdp_rxq);
922 tx_ring = r_vec->xdp_ring;
923
924 while (pkts_polled < budget) {
925 unsigned int meta_len, data_len, meta_off, pkt_len, pkt_off;
926 struct nfp_net_rx_buf *rxbuf;
927 struct nfp_net_rx_desc *rxd;
928 struct nfp_meta_parsed meta;
929 bool redir_egress = false;
930 struct net_device *netdev;
931 dma_addr_t new_dma_addr;
932 u32 meta_len_xdp = 0;
933 void *new_frag;
934
935 idx = D_IDX(rx_ring, rx_ring->rd_p);
936
937 rxd = &rx_ring->rxds[idx];
938 if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
939 break;
940
941 /* Memory barrier to ensure that we won't do other reads
942 * before the DD bit.
943 */
944 dma_rmb();
945
946 memset(&meta, 0, sizeof(meta));
947
948 rx_ring->rd_p++;
949 pkts_polled++;
950
951 rxbuf = &rx_ring->rxbufs[idx];
952 /* < meta_len >
953 * <-- [rx_offset] -->
954 * ---------------------------------------------------------
955 * | [XX] | metadata | packet | XXXX |
956 * ---------------------------------------------------------
957 * <---------------- data_len --------------->
958 *
959 * The rx_offset is fixed for all packets, the meta_len can vary
960 * on a packet by packet basis. If rx_offset is set to zero
961 * (_RX_OFFSET_DYNAMIC) metadata starts at the beginning of the
962 * buffer and is immediately followed by the packet (no [XX]).
963 */
964 meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
965 data_len = le16_to_cpu(rxd->rxd.data_len);
966 pkt_len = data_len - meta_len;
967
968 pkt_off = NFP_NET_RX_BUF_HEADROOM + dp->rx_dma_off;
969 if (dp->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
970 pkt_off += meta_len;
971 else
972 pkt_off += dp->rx_offset;
973 meta_off = pkt_off - meta_len;
974
975 /* Stats update */
976 u64_stats_update_begin(syncp: &r_vec->rx_sync);
977 r_vec->rx_pkts++;
978 r_vec->rx_bytes += pkt_len;
979 u64_stats_update_end(syncp: &r_vec->rx_sync);
980
981 if (unlikely(meta_len > NFP_NET_MAX_PREPEND ||
982 (dp->rx_offset && meta_len > dp->rx_offset))) {
983 nn_dp_warn(dp, "oversized RX packet metadata %u\n",
984 meta_len);
985 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
986 continue;
987 }
988
989 nfp_net_dma_sync_cpu_rx(dp, dma_addr: rxbuf->dma_addr + meta_off,
990 len: data_len);
991
992 if (!dp->chained_metadata_format) {
993 nfp_nfd3_set_hash_desc(netdev: dp->netdev, meta: &meta,
994 data: rxbuf->frag + meta_off, rxd);
995 } else if (meta_len) {
996 if (unlikely(nfp_nfd3_parse_meta(dp->netdev, &meta,
997 rxbuf->frag + meta_off,
998 rxbuf->frag + pkt_off,
999 pkt_len, meta_len))) {
1000 nn_dp_warn(dp, "invalid RX packet metadata\n");
1001 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf,
1002 NULL);
1003 continue;
1004 }
1005 }
1006
1007 if (xdp_prog && !meta.portid) {
1008 void *orig_data = rxbuf->frag + pkt_off;
1009 unsigned int dma_off;
1010 int act;
1011
1012 xdp_prepare_buff(xdp: &xdp,
1013 hard_start: rxbuf->frag + NFP_NET_RX_BUF_HEADROOM,
1014 headroom: pkt_off - NFP_NET_RX_BUF_HEADROOM,
1015 data_len: pkt_len, meta_valid: true);
1016
1017 act = bpf_prog_run_xdp(prog: xdp_prog, xdp: &xdp);
1018
1019 pkt_len = xdp.data_end - xdp.data;
1020 pkt_off += xdp.data - orig_data;
1021
1022 switch (act) {
1023 case XDP_PASS:
1024 meta_len_xdp = xdp.data - xdp.data_meta;
1025 break;
1026 case XDP_TX:
1027 dma_off = pkt_off - NFP_NET_RX_BUF_HEADROOM;
1028 if (unlikely(!nfp_nfd3_tx_xdp_buf(dp, rx_ring,
1029 tx_ring,
1030 rxbuf,
1031 dma_off,
1032 pkt_len,
1033 &xdp_tx_cmpl)))
1034 trace_xdp_exception(dev: dp->netdev,
1035 xdp: xdp_prog, act);
1036 continue;
1037 default:
1038 bpf_warn_invalid_xdp_action(dev: dp->netdev, prog: xdp_prog, act);
1039 fallthrough;
1040 case XDP_ABORTED:
1041 trace_xdp_exception(dev: dp->netdev, xdp: xdp_prog, act);
1042 fallthrough;
1043 case XDP_DROP:
1044 nfp_nfd3_rx_give_one(dp, rx_ring, frag: rxbuf->frag,
1045 dma_addr: rxbuf->dma_addr);
1046 continue;
1047 }
1048 }
1049
1050 if (likely(!meta.portid)) {
1051 netdev = dp->netdev;
1052 } else if (meta.portid == NFP_META_PORT_ID_CTRL) {
1053 struct nfp_net *nn = netdev_priv(dev: dp->netdev);
1054
1055 nfp_app_ctrl_rx_raw(app: nn->app, data: rxbuf->frag + pkt_off,
1056 len: pkt_len);
1057 nfp_nfd3_rx_give_one(dp, rx_ring, frag: rxbuf->frag,
1058 dma_addr: rxbuf->dma_addr);
1059 continue;
1060 } else {
1061 struct nfp_net *nn;
1062
1063 nn = netdev_priv(dev: dp->netdev);
1064 netdev = nfp_app_dev_get(app: nn->app, id: meta.portid,
1065 redir_egress: &redir_egress);
1066 if (unlikely(!netdev)) {
1067 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf,
1068 NULL);
1069 continue;
1070 }
1071
1072 if (nfp_netdev_is_nfp_repr(netdev))
1073 nfp_repr_inc_rx_stats(netdev, len: pkt_len);
1074 }
1075
1076 skb = napi_build_skb(data: rxbuf->frag, frag_size: true_bufsz);
1077 if (unlikely(!skb)) {
1078 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1079 continue;
1080 }
1081 new_frag = nfp_nfd3_napi_alloc_one(dp, dma_addr: &new_dma_addr);
1082 if (unlikely(!new_frag)) {
1083 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, skb);
1084 continue;
1085 }
1086
1087 nfp_net_dma_unmap_rx(dp, dma_addr: rxbuf->dma_addr);
1088
1089 nfp_nfd3_rx_give_one(dp, rx_ring, frag: new_frag, dma_addr: new_dma_addr);
1090
1091 skb_reserve(skb, len: pkt_off);
1092 skb_put(skb, len: pkt_len);
1093
1094 skb->mark = meta.mark;
1095 skb_set_hash(skb, hash: meta.hash, type: meta.hash_type);
1096
1097 skb_record_rx_queue(skb, rx_queue: rx_ring->idx);
1098 skb->protocol = eth_type_trans(skb, dev: netdev);
1099
1100 nfp_nfd3_rx_csum(dp, r_vec, rxd, meta: &meta, skb);
1101
1102#ifdef CONFIG_TLS_DEVICE
1103 if (rxd->rxd.flags & PCIE_DESC_RX_DECRYPTED) {
1104 skb->decrypted = true;
1105 u64_stats_update_begin(syncp: &r_vec->rx_sync);
1106 r_vec->hw_tls_rx++;
1107 u64_stats_update_end(syncp: &r_vec->rx_sync);
1108 }
1109#endif
1110
1111 if (unlikely(!nfp_net_vlan_strip(skb, rxd, &meta))) {
1112 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, NULL, skb);
1113 continue;
1114 }
1115
1116#ifdef CONFIG_NFP_NET_IPSEC
1117 if (meta.ipsec_saidx != 0 && unlikely(nfp_net_ipsec_rx(&meta, skb))) {
1118 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, NULL, skb);
1119 continue;
1120 }
1121#endif
1122
1123 if (meta_len_xdp)
1124 skb_metadata_set(skb, meta_len: meta_len_xdp);
1125
1126 if (likely(!redir_egress)) {
1127 napi_gro_receive(napi: &rx_ring->r_vec->napi, skb);
1128 } else {
1129 skb->dev = netdev;
1130 skb_reset_network_header(skb);
1131 __skb_push(skb, ETH_HLEN);
1132 dev_queue_xmit(skb);
1133 }
1134 }
1135
1136 if (xdp_prog) {
1137 if (tx_ring->wr_ptr_add)
1138 nfp_net_tx_xmit_more_flush(tx_ring);
1139 else if (unlikely(tx_ring->wr_p != tx_ring->rd_p) &&
1140 !xdp_tx_cmpl)
1141 if (!nfp_nfd3_xdp_complete(tx_ring))
1142 pkts_polled = budget;
1143 }
1144
1145 return pkts_polled;
1146}
1147
1148/**
1149 * nfp_nfd3_poll() - napi poll function
1150 * @napi: NAPI structure
1151 * @budget: NAPI budget
1152 *
1153 * Return: number of packets polled.
1154 */
1155int nfp_nfd3_poll(struct napi_struct *napi, int budget)
1156{
1157 struct nfp_net_r_vector *r_vec =
1158 container_of(napi, struct nfp_net_r_vector, napi);
1159 unsigned int pkts_polled = 0;
1160
1161 if (r_vec->tx_ring)
1162 nfp_nfd3_tx_complete(tx_ring: r_vec->tx_ring, budget);
1163 if (r_vec->rx_ring)
1164 pkts_polled = nfp_nfd3_rx(rx_ring: r_vec->rx_ring, budget);
1165
1166 if (pkts_polled < budget)
1167 if (napi_complete_done(n: napi, work_done: pkts_polled))
1168 nfp_net_irq_unmask(nn: r_vec->nfp_net, entry_nr: r_vec->irq_entry);
1169
1170 if (r_vec->nfp_net->rx_coalesce_adapt_on && r_vec->rx_ring) {
1171 struct dim_sample dim_sample = {};
1172 unsigned int start;
1173 u64 pkts, bytes;
1174
1175 do {
1176 start = u64_stats_fetch_begin(syncp: &r_vec->rx_sync);
1177 pkts = r_vec->rx_pkts;
1178 bytes = r_vec->rx_bytes;
1179 } while (u64_stats_fetch_retry(syncp: &r_vec->rx_sync, start));
1180
1181 dim_update_sample(event_ctr: r_vec->event_ctr, packets: pkts, bytes, s: &dim_sample);
1182 net_dim(dim: &r_vec->rx_dim, end_sample: dim_sample);
1183 }
1184
1185 if (r_vec->nfp_net->tx_coalesce_adapt_on && r_vec->tx_ring) {
1186 struct dim_sample dim_sample = {};
1187 unsigned int start;
1188 u64 pkts, bytes;
1189
1190 do {
1191 start = u64_stats_fetch_begin(syncp: &r_vec->tx_sync);
1192 pkts = r_vec->tx_pkts;
1193 bytes = r_vec->tx_bytes;
1194 } while (u64_stats_fetch_retry(syncp: &r_vec->tx_sync, start));
1195
1196 dim_update_sample(event_ctr: r_vec->event_ctr, packets: pkts, bytes, s: &dim_sample);
1197 net_dim(dim: &r_vec->tx_dim, end_sample: dim_sample);
1198 }
1199
1200 return pkts_polled;
1201}
1202
1203/* Control device data path
1204 */
1205
1206bool
1207nfp_nfd3_ctrl_tx_one(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
1208 struct sk_buff *skb, bool old)
1209{
1210 unsigned int real_len = skb->len, meta_len = 0;
1211 struct nfp_net_tx_ring *tx_ring;
1212 struct nfp_nfd3_tx_buf *txbuf;
1213 struct nfp_nfd3_tx_desc *txd;
1214 struct nfp_net_dp *dp;
1215 dma_addr_t dma_addr;
1216 int wr_idx;
1217
1218 dp = &r_vec->nfp_net->dp;
1219 tx_ring = r_vec->tx_ring;
1220
1221 if (WARN_ON_ONCE(skb_shinfo(skb)->nr_frags)) {
1222 nn_dp_warn(dp, "Driver's CTRL TX does not implement gather\n");
1223 goto err_free;
1224 }
1225
1226 if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
1227 u64_stats_update_begin(syncp: &r_vec->tx_sync);
1228 r_vec->tx_busy++;
1229 u64_stats_update_end(syncp: &r_vec->tx_sync);
1230 if (!old)
1231 __skb_queue_tail(list: &r_vec->queue, newsk: skb);
1232 else
1233 __skb_queue_head(list: &r_vec->queue, newsk: skb);
1234 return true;
1235 }
1236
1237 if (nfp_app_ctrl_has_meta(app: nn->app)) {
1238 if (unlikely(skb_headroom(skb) < 8)) {
1239 nn_dp_warn(dp, "CTRL TX on skb without headroom\n");
1240 goto err_free;
1241 }
1242 meta_len = 8;
1243 put_unaligned_be32(NFP_META_PORT_ID_CTRL, p: skb_push(skb, len: 4));
1244 put_unaligned_be32(NFP_NET_META_PORTID, p: skb_push(skb, len: 4));
1245 }
1246
1247 /* Start with the head skbuf */
1248 dma_addr = dma_map_single(dp->dev, skb->data, skb_headlen(skb),
1249 DMA_TO_DEVICE);
1250 if (dma_mapping_error(dev: dp->dev, dma_addr))
1251 goto err_dma_warn;
1252
1253 wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
1254
1255 /* Stash the soft descriptor of the head then initialize it */
1256 txbuf = &tx_ring->txbufs[wr_idx];
1257 txbuf->skb = skb;
1258 txbuf->dma_addr = dma_addr;
1259 txbuf->fidx = -1;
1260 txbuf->pkt_cnt = 1;
1261 txbuf->real_len = real_len;
1262
1263 /* Build TX descriptor */
1264 txd = &tx_ring->txds[wr_idx];
1265 txd->offset_eop = meta_len | NFD3_DESC_TX_EOP;
1266 txd->dma_len = cpu_to_le16(skb_headlen(skb));
1267 nfp_desc_set_dma_addr_40b(txd, dma_addr);
1268 txd->data_len = cpu_to_le16(skb->len);
1269
1270 txd->flags = 0;
1271 txd->mss = 0;
1272 txd->lso_hdrlen = 0;
1273
1274 tx_ring->wr_p++;
1275 tx_ring->wr_ptr_add++;
1276 nfp_net_tx_xmit_more_flush(tx_ring);
1277
1278 return false;
1279
1280err_dma_warn:
1281 nn_dp_warn(dp, "Failed to DMA map TX CTRL buffer\n");
1282err_free:
1283 u64_stats_update_begin(syncp: &r_vec->tx_sync);
1284 r_vec->tx_errors++;
1285 u64_stats_update_end(syncp: &r_vec->tx_sync);
1286 dev_kfree_skb_any(skb);
1287 return false;
1288}
1289
1290static void __nfp_ctrl_tx_queued(struct nfp_net_r_vector *r_vec)
1291{
1292 struct sk_buff *skb;
1293
1294 while ((skb = __skb_dequeue(list: &r_vec->queue)))
1295 if (nfp_nfd3_ctrl_tx_one(nn: r_vec->nfp_net, r_vec, skb, old: true))
1296 return;
1297}
1298
1299static bool
1300nfp_ctrl_meta_ok(struct nfp_net *nn, void *data, unsigned int meta_len)
1301{
1302 u32 meta_type, meta_tag;
1303
1304 if (!nfp_app_ctrl_has_meta(app: nn->app))
1305 return !meta_len;
1306
1307 if (meta_len != 8)
1308 return false;
1309
1310 meta_type = get_unaligned_be32(p: data);
1311 meta_tag = get_unaligned_be32(p: data + 4);
1312
1313 return (meta_type == NFP_NET_META_PORTID &&
1314 meta_tag == NFP_META_PORT_ID_CTRL);
1315}
1316
1317static bool
1318nfp_ctrl_rx_one(struct nfp_net *nn, struct nfp_net_dp *dp,
1319 struct nfp_net_r_vector *r_vec, struct nfp_net_rx_ring *rx_ring)
1320{
1321 unsigned int meta_len, data_len, meta_off, pkt_len, pkt_off;
1322 struct nfp_net_rx_buf *rxbuf;
1323 struct nfp_net_rx_desc *rxd;
1324 dma_addr_t new_dma_addr;
1325 struct sk_buff *skb;
1326 void *new_frag;
1327 int idx;
1328
1329 idx = D_IDX(rx_ring, rx_ring->rd_p);
1330
1331 rxd = &rx_ring->rxds[idx];
1332 if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
1333 return false;
1334
1335 /* Memory barrier to ensure that we won't do other reads
1336 * before the DD bit.
1337 */
1338 dma_rmb();
1339
1340 rx_ring->rd_p++;
1341
1342 rxbuf = &rx_ring->rxbufs[idx];
1343 meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
1344 data_len = le16_to_cpu(rxd->rxd.data_len);
1345 pkt_len = data_len - meta_len;
1346
1347 pkt_off = NFP_NET_RX_BUF_HEADROOM + dp->rx_dma_off;
1348 if (dp->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
1349 pkt_off += meta_len;
1350 else
1351 pkt_off += dp->rx_offset;
1352 meta_off = pkt_off - meta_len;
1353
1354 /* Stats update */
1355 u64_stats_update_begin(syncp: &r_vec->rx_sync);
1356 r_vec->rx_pkts++;
1357 r_vec->rx_bytes += pkt_len;
1358 u64_stats_update_end(syncp: &r_vec->rx_sync);
1359
1360 nfp_net_dma_sync_cpu_rx(dp, dma_addr: rxbuf->dma_addr + meta_off, len: data_len);
1361
1362 if (unlikely(!nfp_ctrl_meta_ok(nn, rxbuf->frag + meta_off, meta_len))) {
1363 nn_dp_warn(dp, "incorrect metadata for ctrl packet (%d)\n",
1364 meta_len);
1365 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1366 return true;
1367 }
1368
1369 skb = build_skb(data: rxbuf->frag, frag_size: dp->fl_bufsz);
1370 if (unlikely(!skb)) {
1371 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1372 return true;
1373 }
1374 new_frag = nfp_nfd3_napi_alloc_one(dp, dma_addr: &new_dma_addr);
1375 if (unlikely(!new_frag)) {
1376 nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, skb);
1377 return true;
1378 }
1379
1380 nfp_net_dma_unmap_rx(dp, dma_addr: rxbuf->dma_addr);
1381
1382 nfp_nfd3_rx_give_one(dp, rx_ring, frag: new_frag, dma_addr: new_dma_addr);
1383
1384 skb_reserve(skb, len: pkt_off);
1385 skb_put(skb, len: pkt_len);
1386
1387 nfp_app_ctrl_rx(app: nn->app, skb);
1388
1389 return true;
1390}
1391
1392static bool nfp_ctrl_rx(struct nfp_net_r_vector *r_vec)
1393{
1394 struct nfp_net_rx_ring *rx_ring = r_vec->rx_ring;
1395 struct nfp_net *nn = r_vec->nfp_net;
1396 struct nfp_net_dp *dp = &nn->dp;
1397 unsigned int budget = 512;
1398
1399 while (nfp_ctrl_rx_one(nn, dp, r_vec, rx_ring) && budget--)
1400 continue;
1401
1402 return budget;
1403}
1404
1405void nfp_nfd3_ctrl_poll(struct tasklet_struct *t)
1406{
1407 struct nfp_net_r_vector *r_vec = from_tasklet(r_vec, t, tasklet);
1408
1409 spin_lock(lock: &r_vec->lock);
1410 nfp_nfd3_tx_complete(tx_ring: r_vec->tx_ring, budget: 0);
1411 __nfp_ctrl_tx_queued(r_vec);
1412 spin_unlock(lock: &r_vec->lock);
1413
1414 if (nfp_ctrl_rx(r_vec)) {
1415 nfp_net_irq_unmask(nn: r_vec->nfp_net, entry_nr: r_vec->irq_entry);
1416 } else {
1417 tasklet_schedule(t: &r_vec->tasklet);
1418 nn_dp_warn(&r_vec->nfp_net->dp,
1419 "control message budget exceeded!\n");
1420 }
1421}
1422

source code of linux/drivers/net/ethernet/netronome/nfp/nfd3/dp.c