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/overflow.h>
7 #include <linux/sizes.h>
8 #include <linux/bitfield.h>
9 
10 #include "../nfp_app.h"
11 #include "../nfp_net.h"
12 #include "../nfp_net_dp.h"
13 #include "../crypto/crypto.h"
14 #include "../crypto/fw.h"
15 #include "nfdk.h"
16 
nfp_nfdk_tx_ring_should_wake(struct nfp_net_tx_ring * tx_ring)17 static int nfp_nfdk_tx_ring_should_wake(struct nfp_net_tx_ring *tx_ring)
18 {
19 	return !nfp_net_tx_full(tx_ring, NFDK_TX_DESC_STOP_CNT * 2);
20 }
21 
nfp_nfdk_tx_ring_should_stop(struct nfp_net_tx_ring * tx_ring)22 static int nfp_nfdk_tx_ring_should_stop(struct nfp_net_tx_ring *tx_ring)
23 {
24 	return nfp_net_tx_full(tx_ring, NFDK_TX_DESC_STOP_CNT);
25 }
26 
nfp_nfdk_tx_ring_stop(struct netdev_queue * nd_q,struct nfp_net_tx_ring * tx_ring)27 static void nfp_nfdk_tx_ring_stop(struct netdev_queue *nd_q,
28 				  struct nfp_net_tx_ring *tx_ring)
29 {
30 	netif_tx_stop_queue(nd_q);
31 
32 	/* We can race with the TX completion out of NAPI so recheck */
33 	smp_mb();
34 	if (unlikely(nfp_nfdk_tx_ring_should_wake(tx_ring)))
35 		netif_tx_start_queue(nd_q);
36 }
37 
38 static __le64
nfp_nfdk_tx_tso(struct nfp_net_r_vector * r_vec,struct nfp_nfdk_tx_buf * txbuf,struct sk_buff * skb)39 nfp_nfdk_tx_tso(struct nfp_net_r_vector *r_vec, struct nfp_nfdk_tx_buf *txbuf,
40 		struct sk_buff *skb)
41 {
42 	u32 segs, hdrlen, l3_offset, l4_offset;
43 	struct nfp_nfdk_tx_desc txd;
44 	u16 mss;
45 
46 	if (!skb->encapsulation) {
47 		l3_offset = skb_network_offset(skb);
48 		l4_offset = skb_transport_offset(skb);
49 		hdrlen = skb_tcp_all_headers(skb);
50 	} else {
51 		l3_offset = skb_inner_network_offset(skb);
52 		l4_offset = skb_inner_transport_offset(skb);
53 		hdrlen = skb_inner_tcp_all_headers(skb);
54 	}
55 
56 	segs = skb_shinfo(skb)->gso_segs;
57 	mss = skb_shinfo(skb)->gso_size & NFDK_DESC_TX_MSS_MASK;
58 
59 	txd.l3_offset = l3_offset;
60 	txd.l4_offset = l4_offset;
61 	txd.lso_meta_res = 0;
62 	txd.mss = cpu_to_le16(mss);
63 	txd.lso_hdrlen = hdrlen;
64 	txd.lso_totsegs = segs;
65 
66 	txbuf->pkt_cnt = segs;
67 	txbuf->real_len = skb->len + hdrlen * (txbuf->pkt_cnt - 1);
68 
69 	u64_stats_update_begin(&r_vec->tx_sync);
70 	r_vec->tx_lso++;
71 	u64_stats_update_end(&r_vec->tx_sync);
72 
73 	return txd.raw;
74 }
75 
76 static u8
nfp_nfdk_tx_csum(struct nfp_net_dp * dp,struct nfp_net_r_vector * r_vec,unsigned int pkt_cnt,struct sk_buff * skb,u64 flags)77 nfp_nfdk_tx_csum(struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
78 		 unsigned int pkt_cnt, struct sk_buff *skb, u64 flags)
79 {
80 	struct ipv6hdr *ipv6h;
81 	struct iphdr *iph;
82 
83 	if (!(dp->ctrl & NFP_NET_CFG_CTRL_TXCSUM))
84 		return flags;
85 
86 	if (skb->ip_summed != CHECKSUM_PARTIAL)
87 		return flags;
88 
89 	flags |= NFDK_DESC_TX_L4_CSUM;
90 
91 	iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
92 	ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);
93 
94 	/* L3 checksum offloading flag is not required for ipv6 */
95 	if (iph->version == 4) {
96 		flags |= NFDK_DESC_TX_L3_CSUM;
97 	} else if (ipv6h->version != 6) {
98 		nn_dp_warn(dp, "partial checksum but ipv=%x!\n", iph->version);
99 		return flags;
100 	}
101 
102 	u64_stats_update_begin(&r_vec->tx_sync);
103 	if (!skb->encapsulation) {
104 		r_vec->hw_csum_tx += pkt_cnt;
105 	} else {
106 		flags |= NFDK_DESC_TX_ENCAP;
107 		r_vec->hw_csum_tx_inner += pkt_cnt;
108 	}
109 	u64_stats_update_end(&r_vec->tx_sync);
110 
111 	return flags;
112 }
113 
114 static int
nfp_nfdk_tx_maybe_close_block(struct nfp_net_tx_ring * tx_ring,struct sk_buff * skb)115 nfp_nfdk_tx_maybe_close_block(struct nfp_net_tx_ring *tx_ring,
116 			      struct sk_buff *skb)
117 {
118 	unsigned int n_descs, wr_p, nop_slots;
119 	const skb_frag_t *frag, *fend;
120 	struct nfp_nfdk_tx_desc *txd;
121 	unsigned int nr_frags;
122 	unsigned int wr_idx;
123 	int err;
124 
125 recount_descs:
126 	n_descs = nfp_nfdk_headlen_to_segs(skb_headlen(skb));
127 	nr_frags = skb_shinfo(skb)->nr_frags;
128 	frag = skb_shinfo(skb)->frags;
129 	fend = frag + nr_frags;
130 	for (; frag < fend; frag++)
131 		n_descs += DIV_ROUND_UP(skb_frag_size(frag),
132 					NFDK_TX_MAX_DATA_PER_DESC);
133 
134 	if (unlikely(n_descs > NFDK_TX_DESC_GATHER_MAX)) {
135 		if (skb_is_nonlinear(skb)) {
136 			err = skb_linearize(skb);
137 			if (err)
138 				return err;
139 			goto recount_descs;
140 		}
141 		return -EINVAL;
142 	}
143 
144 	/* Under count by 1 (don't count meta) for the round down to work out */
145 	n_descs += !!skb_is_gso(skb);
146 
147 	if (round_down(tx_ring->wr_p, NFDK_TX_DESC_BLOCK_CNT) !=
148 	    round_down(tx_ring->wr_p + n_descs, NFDK_TX_DESC_BLOCK_CNT))
149 		goto close_block;
150 
151 	if ((u32)tx_ring->data_pending + skb->len > NFDK_TX_MAX_DATA_PER_BLOCK)
152 		goto close_block;
153 
154 	return 0;
155 
156 close_block:
157 	wr_p = tx_ring->wr_p;
158 	nop_slots = D_BLOCK_CPL(wr_p);
159 
160 	wr_idx = D_IDX(tx_ring, wr_p);
161 	tx_ring->ktxbufs[wr_idx].skb = NULL;
162 	txd = &tx_ring->ktxds[wr_idx];
163 
164 	memset(txd, 0, array_size(nop_slots, sizeof(struct nfp_nfdk_tx_desc)));
165 
166 	tx_ring->data_pending = 0;
167 	tx_ring->wr_p += nop_slots;
168 	tx_ring->wr_ptr_add += nop_slots;
169 
170 	return 0;
171 }
172 
173 static int
nfp_nfdk_prep_tx_meta(struct nfp_net_dp * dp,struct nfp_app * app,struct sk_buff * skb)174 nfp_nfdk_prep_tx_meta(struct nfp_net_dp *dp, struct nfp_app *app,
175 		      struct sk_buff *skb)
176 {
177 	struct metadata_dst *md_dst = skb_metadata_dst(skb);
178 	unsigned char *data;
179 	bool vlan_insert;
180 	u32 meta_id = 0;
181 	int md_bytes;
182 
183 	if (unlikely(md_dst && md_dst->type != METADATA_HW_PORT_MUX))
184 		md_dst = NULL;
185 
186 	vlan_insert = skb_vlan_tag_present(skb) && (dp->ctrl & NFP_NET_CFG_CTRL_TXVLAN_V2);
187 
188 	if (!(md_dst || vlan_insert))
189 		return 0;
190 
191 	md_bytes = sizeof(meta_id) +
192 		   !!md_dst * NFP_NET_META_PORTID_SIZE +
193 		   vlan_insert * NFP_NET_META_VLAN_SIZE;
194 
195 	if (unlikely(skb_cow_head(skb, md_bytes)))
196 		return -ENOMEM;
197 
198 	data = skb_push(skb, md_bytes) + md_bytes;
199 	if (md_dst) {
200 		data -= NFP_NET_META_PORTID_SIZE;
201 		put_unaligned_be32(md_dst->u.port_info.port_id, data);
202 		meta_id = NFP_NET_META_PORTID;
203 	}
204 	if (vlan_insert) {
205 		data -= NFP_NET_META_VLAN_SIZE;
206 		/* data type of skb->vlan_proto is __be16
207 		 * so it fills metadata without calling put_unaligned_be16
208 		 */
209 		memcpy(data, &skb->vlan_proto, sizeof(skb->vlan_proto));
210 		put_unaligned_be16(skb_vlan_tag_get(skb), data + sizeof(skb->vlan_proto));
211 		meta_id <<= NFP_NET_META_FIELD_SIZE;
212 		meta_id |= NFP_NET_META_VLAN;
213 	}
214 
215 	meta_id = FIELD_PREP(NFDK_META_LEN, md_bytes) |
216 		  FIELD_PREP(NFDK_META_FIELDS, meta_id);
217 
218 	data -= sizeof(meta_id);
219 	put_unaligned_be32(meta_id, data);
220 
221 	return NFDK_DESC_TX_CHAIN_META;
222 }
223 
224 /**
225  * nfp_nfdk_tx() - Main transmit entry point
226  * @skb:    SKB to transmit
227  * @netdev: netdev structure
228  *
229  * Return: NETDEV_TX_OK on success.
230  */
nfp_nfdk_tx(struct sk_buff * skb,struct net_device * netdev)231 netdev_tx_t nfp_nfdk_tx(struct sk_buff *skb, struct net_device *netdev)
232 {
233 	struct nfp_net *nn = netdev_priv(netdev);
234 	struct nfp_nfdk_tx_buf *txbuf, *etxbuf;
235 	u32 cnt, tmp_dlen, dlen_type = 0;
236 	struct nfp_net_tx_ring *tx_ring;
237 	struct nfp_net_r_vector *r_vec;
238 	const skb_frag_t *frag, *fend;
239 	struct nfp_nfdk_tx_desc *txd;
240 	unsigned int real_len, qidx;
241 	unsigned int dma_len, type;
242 	struct netdev_queue *nd_q;
243 	struct nfp_net_dp *dp;
244 	int nr_frags, wr_idx;
245 	dma_addr_t dma_addr;
246 	u64 metadata;
247 
248 	dp = &nn->dp;
249 	qidx = skb_get_queue_mapping(skb);
250 	tx_ring = &dp->tx_rings[qidx];
251 	r_vec = tx_ring->r_vec;
252 	nd_q = netdev_get_tx_queue(dp->netdev, qidx);
253 
254 	/* Don't bother counting frags, assume the worst */
255 	if (unlikely(nfp_net_tx_full(tx_ring, NFDK_TX_DESC_STOP_CNT))) {
256 		nn_dp_warn(dp, "TX ring %d busy. wrp=%u rdp=%u\n",
257 			   qidx, tx_ring->wr_p, tx_ring->rd_p);
258 		netif_tx_stop_queue(nd_q);
259 		nfp_net_tx_xmit_more_flush(tx_ring);
260 		u64_stats_update_begin(&r_vec->tx_sync);
261 		r_vec->tx_busy++;
262 		u64_stats_update_end(&r_vec->tx_sync);
263 		return NETDEV_TX_BUSY;
264 	}
265 
266 	metadata = nfp_nfdk_prep_tx_meta(dp, nn->app, skb);
267 	if (unlikely((int)metadata < 0))
268 		goto err_flush;
269 
270 	if (nfp_nfdk_tx_maybe_close_block(tx_ring, skb))
271 		goto err_flush;
272 
273 	/* nr_frags will change after skb_linearize so we get nr_frags after
274 	 * nfp_nfdk_tx_maybe_close_block function
275 	 */
276 	nr_frags = skb_shinfo(skb)->nr_frags;
277 	/* DMA map all */
278 	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
279 	txd = &tx_ring->ktxds[wr_idx];
280 	txbuf = &tx_ring->ktxbufs[wr_idx];
281 
282 	dma_len = skb_headlen(skb);
283 	if (skb_is_gso(skb))
284 		type = NFDK_DESC_TX_TYPE_TSO;
285 	else if (!nr_frags && dma_len <= NFDK_TX_MAX_DATA_PER_HEAD)
286 		type = NFDK_DESC_TX_TYPE_SIMPLE;
287 	else
288 		type = NFDK_DESC_TX_TYPE_GATHER;
289 
290 	dma_addr = dma_map_single(dp->dev, skb->data, dma_len, DMA_TO_DEVICE);
291 	if (dma_mapping_error(dp->dev, dma_addr))
292 		goto err_warn_dma;
293 
294 	txbuf->skb = skb;
295 	txbuf++;
296 
297 	txbuf->dma_addr = dma_addr;
298 	txbuf++;
299 
300 	/* FIELD_PREP() implicitly truncates to chunk */
301 	dma_len -= 1;
302 
303 	/* We will do our best to pass as much data as we can in descriptor
304 	 * and we need to make sure the first descriptor includes whole head
305 	 * since there is limitation in firmware side. Sometimes the value of
306 	 * dma_len bitwise and NFDK_DESC_TX_DMA_LEN_HEAD will less than
307 	 * headlen.
308 	 */
309 	dlen_type = FIELD_PREP(NFDK_DESC_TX_DMA_LEN_HEAD,
310 			       dma_len > NFDK_DESC_TX_DMA_LEN_HEAD ?
311 			       NFDK_DESC_TX_DMA_LEN_HEAD : dma_len) |
312 		    FIELD_PREP(NFDK_DESC_TX_TYPE_HEAD, type);
313 
314 	txd->dma_len_type = cpu_to_le16(dlen_type);
315 	nfp_desc_set_dma_addr_48b(txd, dma_addr);
316 
317 	/* starts at bit 0 */
318 	BUILD_BUG_ON(!(NFDK_DESC_TX_DMA_LEN_HEAD & 1));
319 
320 	/* Preserve the original dlen_type, this way below the EOP logic
321 	 * can use dlen_type.
322 	 */
323 	tmp_dlen = dlen_type & NFDK_DESC_TX_DMA_LEN_HEAD;
324 	dma_len -= tmp_dlen;
325 	dma_addr += tmp_dlen + 1;
326 	txd++;
327 
328 	/* The rest of the data (if any) will be in larger dma descritors
329 	 * and is handled with the fragment loop.
330 	 */
331 	frag = skb_shinfo(skb)->frags;
332 	fend = frag + nr_frags;
333 
334 	while (true) {
335 		while (dma_len > 0) {
336 			dma_len -= 1;
337 			dlen_type = FIELD_PREP(NFDK_DESC_TX_DMA_LEN, dma_len);
338 
339 			txd->dma_len_type = cpu_to_le16(dlen_type);
340 			nfp_desc_set_dma_addr_48b(txd, dma_addr);
341 
342 			dma_len -= dlen_type;
343 			dma_addr += dlen_type + 1;
344 			txd++;
345 		}
346 
347 		if (frag >= fend)
348 			break;
349 
350 		dma_len = skb_frag_size(frag);
351 		dma_addr = skb_frag_dma_map(dp->dev, frag, 0, dma_len,
352 					    DMA_TO_DEVICE);
353 		if (dma_mapping_error(dp->dev, dma_addr))
354 			goto err_unmap;
355 
356 		txbuf->dma_addr = dma_addr;
357 		txbuf++;
358 
359 		frag++;
360 	}
361 
362 	(txd - 1)->dma_len_type = cpu_to_le16(dlen_type | NFDK_DESC_TX_EOP);
363 
364 	if (!skb_is_gso(skb)) {
365 		real_len = skb->len;
366 		/* Metadata desc */
367 		metadata = nfp_nfdk_tx_csum(dp, r_vec, 1, skb, metadata);
368 		txd->raw = cpu_to_le64(metadata);
369 		txd++;
370 	} else {
371 		/* lso desc should be placed after metadata desc */
372 		(txd + 1)->raw = nfp_nfdk_tx_tso(r_vec, txbuf, skb);
373 		real_len = txbuf->real_len;
374 		/* Metadata desc */
375 		metadata = nfp_nfdk_tx_csum(dp, r_vec, txbuf->pkt_cnt, skb, metadata);
376 		txd->raw = cpu_to_le64(metadata);
377 		txd += 2;
378 		txbuf++;
379 	}
380 
381 	cnt = txd - tx_ring->ktxds - wr_idx;
382 	if (unlikely(round_down(wr_idx, NFDK_TX_DESC_BLOCK_CNT) !=
383 		     round_down(wr_idx + cnt - 1, NFDK_TX_DESC_BLOCK_CNT)))
384 		goto err_warn_overflow;
385 
386 	skb_tx_timestamp(skb);
387 
388 	tx_ring->wr_p += cnt;
389 	if (tx_ring->wr_p % NFDK_TX_DESC_BLOCK_CNT)
390 		tx_ring->data_pending += skb->len;
391 	else
392 		tx_ring->data_pending = 0;
393 
394 	if (nfp_nfdk_tx_ring_should_stop(tx_ring))
395 		nfp_nfdk_tx_ring_stop(nd_q, tx_ring);
396 
397 	tx_ring->wr_ptr_add += cnt;
398 	if (__netdev_tx_sent_queue(nd_q, real_len, netdev_xmit_more()))
399 		nfp_net_tx_xmit_more_flush(tx_ring);
400 
401 	return NETDEV_TX_OK;
402 
403 err_warn_overflow:
404 	WARN_ONCE(1, "unable to fit packet into a descriptor wr_idx:%d head:%d frags:%d cnt:%d",
405 		  wr_idx, skb_headlen(skb), nr_frags, cnt);
406 	if (skb_is_gso(skb))
407 		txbuf--;
408 err_unmap:
409 	/* txbuf pointed to the next-to-use */
410 	etxbuf = txbuf;
411 	/* first txbuf holds the skb */
412 	txbuf = &tx_ring->ktxbufs[wr_idx + 1];
413 	if (txbuf < etxbuf) {
414 		dma_unmap_single(dp->dev, txbuf->dma_addr,
415 				 skb_headlen(skb), DMA_TO_DEVICE);
416 		txbuf->raw = 0;
417 		txbuf++;
418 	}
419 	frag = skb_shinfo(skb)->frags;
420 	while (etxbuf < txbuf) {
421 		dma_unmap_page(dp->dev, txbuf->dma_addr,
422 			       skb_frag_size(frag), DMA_TO_DEVICE);
423 		txbuf->raw = 0;
424 		frag++;
425 		txbuf++;
426 	}
427 err_warn_dma:
428 	nn_dp_warn(dp, "Failed to map DMA TX buffer\n");
429 err_flush:
430 	nfp_net_tx_xmit_more_flush(tx_ring);
431 	u64_stats_update_begin(&r_vec->tx_sync);
432 	r_vec->tx_errors++;
433 	u64_stats_update_end(&r_vec->tx_sync);
434 	dev_kfree_skb_any(skb);
435 	return NETDEV_TX_OK;
436 }
437 
438 /**
439  * nfp_nfdk_tx_complete() - Handled completed TX packets
440  * @tx_ring:	TX ring structure
441  * @budget:	NAPI budget (only used as bool to determine if in NAPI context)
442  */
nfp_nfdk_tx_complete(struct nfp_net_tx_ring * tx_ring,int budget)443 static void nfp_nfdk_tx_complete(struct nfp_net_tx_ring *tx_ring, int budget)
444 {
445 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
446 	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
447 	u32 done_pkts = 0, done_bytes = 0;
448 	struct nfp_nfdk_tx_buf *ktxbufs;
449 	struct device *dev = dp->dev;
450 	struct netdev_queue *nd_q;
451 	u32 rd_p, qcp_rd_p;
452 	int todo;
453 
454 	rd_p = tx_ring->rd_p;
455 	if (tx_ring->wr_p == rd_p)
456 		return;
457 
458 	/* Work out how many descriptors have been transmitted */
459 	qcp_rd_p = nfp_net_read_tx_cmpl(tx_ring, dp);
460 
461 	if (qcp_rd_p == tx_ring->qcp_rd_p)
462 		return;
463 
464 	todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);
465 	ktxbufs = tx_ring->ktxbufs;
466 
467 	while (todo > 0) {
468 		const skb_frag_t *frag, *fend;
469 		unsigned int size, n_descs = 1;
470 		struct nfp_nfdk_tx_buf *txbuf;
471 		struct sk_buff *skb;
472 
473 		txbuf = &ktxbufs[D_IDX(tx_ring, rd_p)];
474 		skb = txbuf->skb;
475 		txbuf++;
476 
477 		/* Closed block */
478 		if (!skb) {
479 			n_descs = D_BLOCK_CPL(rd_p);
480 			goto next;
481 		}
482 
483 		/* Unmap head */
484 		size = skb_headlen(skb);
485 		n_descs += nfp_nfdk_headlen_to_segs(size);
486 		dma_unmap_single(dev, txbuf->dma_addr, size, DMA_TO_DEVICE);
487 		txbuf++;
488 
489 		/* Unmap frags */
490 		frag = skb_shinfo(skb)->frags;
491 		fend = frag + skb_shinfo(skb)->nr_frags;
492 		for (; frag < fend; frag++) {
493 			size = skb_frag_size(frag);
494 			n_descs += DIV_ROUND_UP(size,
495 						NFDK_TX_MAX_DATA_PER_DESC);
496 			dma_unmap_page(dev, txbuf->dma_addr,
497 				       skb_frag_size(frag), DMA_TO_DEVICE);
498 			txbuf++;
499 		}
500 
501 		if (!skb_is_gso(skb)) {
502 			done_bytes += skb->len;
503 			done_pkts++;
504 		} else {
505 			done_bytes += txbuf->real_len;
506 			done_pkts += txbuf->pkt_cnt;
507 			n_descs++;
508 		}
509 
510 		napi_consume_skb(skb, budget);
511 next:
512 		rd_p += n_descs;
513 		todo -= n_descs;
514 	}
515 
516 	tx_ring->rd_p = rd_p;
517 	tx_ring->qcp_rd_p = qcp_rd_p;
518 
519 	u64_stats_update_begin(&r_vec->tx_sync);
520 	r_vec->tx_bytes += done_bytes;
521 	r_vec->tx_pkts += done_pkts;
522 	u64_stats_update_end(&r_vec->tx_sync);
523 
524 	if (!dp->netdev)
525 		return;
526 
527 	nd_q = netdev_get_tx_queue(dp->netdev, tx_ring->idx);
528 	netdev_tx_completed_queue(nd_q, done_pkts, done_bytes);
529 	if (nfp_nfdk_tx_ring_should_wake(tx_ring)) {
530 		/* Make sure TX thread will see updated tx_ring->rd_p */
531 		smp_mb();
532 
533 		if (unlikely(netif_tx_queue_stopped(nd_q)))
534 			netif_tx_wake_queue(nd_q);
535 	}
536 
537 	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
538 		  "TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
539 		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
540 }
541 
542 /* Receive processing */
543 static void *
nfp_nfdk_napi_alloc_one(struct nfp_net_dp * dp,dma_addr_t * dma_addr)544 nfp_nfdk_napi_alloc_one(struct nfp_net_dp *dp, dma_addr_t *dma_addr)
545 {
546 	void *frag;
547 
548 	if (!dp->xdp_prog) {
549 		frag = napi_alloc_frag(dp->fl_bufsz);
550 		if (unlikely(!frag))
551 			return NULL;
552 	} else {
553 		struct page *page;
554 
555 		page = dev_alloc_page();
556 		if (unlikely(!page))
557 			return NULL;
558 		frag = page_address(page);
559 	}
560 
561 	*dma_addr = nfp_net_dma_map_rx(dp, frag);
562 	if (dma_mapping_error(dp->dev, *dma_addr)) {
563 		nfp_net_free_frag(frag, dp->xdp_prog);
564 		nn_dp_warn(dp, "Failed to map DMA RX buffer\n");
565 		return NULL;
566 	}
567 
568 	return frag;
569 }
570 
571 /**
572  * nfp_nfdk_rx_give_one() - Put mapped skb on the software and hardware rings
573  * @dp:		NFP Net data path struct
574  * @rx_ring:	RX ring structure
575  * @frag:	page fragment buffer
576  * @dma_addr:	DMA address of skb mapping
577  */
578 static void
nfp_nfdk_rx_give_one(const struct nfp_net_dp * dp,struct nfp_net_rx_ring * rx_ring,void * frag,dma_addr_t dma_addr)579 nfp_nfdk_rx_give_one(const struct nfp_net_dp *dp,
580 		     struct nfp_net_rx_ring *rx_ring,
581 		     void *frag, dma_addr_t dma_addr)
582 {
583 	unsigned int wr_idx;
584 
585 	wr_idx = D_IDX(rx_ring, rx_ring->wr_p);
586 
587 	nfp_net_dma_sync_dev_rx(dp, dma_addr);
588 
589 	/* Stash SKB and DMA address away */
590 	rx_ring->rxbufs[wr_idx].frag = frag;
591 	rx_ring->rxbufs[wr_idx].dma_addr = dma_addr;
592 
593 	/* Fill freelist descriptor */
594 	rx_ring->rxds[wr_idx].fld.reserved = 0;
595 	rx_ring->rxds[wr_idx].fld.meta_len_dd = 0;
596 	nfp_desc_set_dma_addr_48b(&rx_ring->rxds[wr_idx].fld,
597 				  dma_addr + dp->rx_dma_off);
598 
599 	rx_ring->wr_p++;
600 	if (!(rx_ring->wr_p % NFP_NET_FL_BATCH)) {
601 		/* Update write pointer of the freelist queue. Make
602 		 * sure all writes are flushed before telling the hardware.
603 		 */
604 		wmb();
605 		nfp_qcp_wr_ptr_add(rx_ring->qcp_fl, NFP_NET_FL_BATCH);
606 	}
607 }
608 
609 /**
610  * nfp_nfdk_rx_ring_fill_freelist() - Give buffers from the ring to FW
611  * @dp:	     NFP Net data path struct
612  * @rx_ring: RX ring to fill
613  */
nfp_nfdk_rx_ring_fill_freelist(struct nfp_net_dp * dp,struct nfp_net_rx_ring * rx_ring)614 void nfp_nfdk_rx_ring_fill_freelist(struct nfp_net_dp *dp,
615 				    struct nfp_net_rx_ring *rx_ring)
616 {
617 	unsigned int i;
618 
619 	for (i = 0; i < rx_ring->cnt - 1; i++)
620 		nfp_nfdk_rx_give_one(dp, rx_ring, rx_ring->rxbufs[i].frag,
621 				     rx_ring->rxbufs[i].dma_addr);
622 }
623 
624 /**
625  * nfp_nfdk_rx_csum_has_errors() - group check if rxd has any csum errors
626  * @flags: RX descriptor flags field in CPU byte order
627  */
nfp_nfdk_rx_csum_has_errors(u16 flags)628 static int nfp_nfdk_rx_csum_has_errors(u16 flags)
629 {
630 	u16 csum_all_checked, csum_all_ok;
631 
632 	csum_all_checked = flags & __PCIE_DESC_RX_CSUM_ALL;
633 	csum_all_ok = flags & __PCIE_DESC_RX_CSUM_ALL_OK;
634 
635 	return csum_all_checked != (csum_all_ok << PCIE_DESC_RX_CSUM_OK_SHIFT);
636 }
637 
638 /**
639  * nfp_nfdk_rx_csum() - set SKB checksum field based on RX descriptor flags
640  * @dp:  NFP Net data path struct
641  * @r_vec: per-ring structure
642  * @rxd: Pointer to RX descriptor
643  * @meta: Parsed metadata prepend
644  * @skb: Pointer to SKB
645  */
646 static void
nfp_nfdk_rx_csum(struct nfp_net_dp * dp,struct nfp_net_r_vector * r_vec,struct nfp_net_rx_desc * rxd,struct nfp_meta_parsed * meta,struct sk_buff * skb)647 nfp_nfdk_rx_csum(struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
648 		 struct nfp_net_rx_desc *rxd, struct nfp_meta_parsed *meta,
649 		 struct sk_buff *skb)
650 {
651 	skb_checksum_none_assert(skb);
652 
653 	if (!(dp->netdev->features & NETIF_F_RXCSUM))
654 		return;
655 
656 	if (meta->csum_type) {
657 		skb->ip_summed = meta->csum_type;
658 		skb->csum = meta->csum;
659 		u64_stats_update_begin(&r_vec->rx_sync);
660 		r_vec->hw_csum_rx_complete++;
661 		u64_stats_update_end(&r_vec->rx_sync);
662 		return;
663 	}
664 
665 	if (nfp_nfdk_rx_csum_has_errors(le16_to_cpu(rxd->rxd.flags))) {
666 		u64_stats_update_begin(&r_vec->rx_sync);
667 		r_vec->hw_csum_rx_error++;
668 		u64_stats_update_end(&r_vec->rx_sync);
669 		return;
670 	}
671 
672 	/* Assume that the firmware will never report inner CSUM_OK unless outer
673 	 * L4 headers were successfully parsed. FW will always report zero UDP
674 	 * checksum as CSUM_OK.
675 	 */
676 	if (rxd->rxd.flags & PCIE_DESC_RX_TCP_CSUM_OK ||
677 	    rxd->rxd.flags & PCIE_DESC_RX_UDP_CSUM_OK) {
678 		__skb_incr_checksum_unnecessary(skb);
679 		u64_stats_update_begin(&r_vec->rx_sync);
680 		r_vec->hw_csum_rx_ok++;
681 		u64_stats_update_end(&r_vec->rx_sync);
682 	}
683 
684 	if (rxd->rxd.flags & PCIE_DESC_RX_I_TCP_CSUM_OK ||
685 	    rxd->rxd.flags & PCIE_DESC_RX_I_UDP_CSUM_OK) {
686 		__skb_incr_checksum_unnecessary(skb);
687 		u64_stats_update_begin(&r_vec->rx_sync);
688 		r_vec->hw_csum_rx_inner_ok++;
689 		u64_stats_update_end(&r_vec->rx_sync);
690 	}
691 }
692 
693 static void
nfp_nfdk_set_hash(struct net_device * netdev,struct nfp_meta_parsed * meta,unsigned int type,__be32 * hash)694 nfp_nfdk_set_hash(struct net_device *netdev, struct nfp_meta_parsed *meta,
695 		  unsigned int type, __be32 *hash)
696 {
697 	if (!(netdev->features & NETIF_F_RXHASH))
698 		return;
699 
700 	switch (type) {
701 	case NFP_NET_RSS_IPV4:
702 	case NFP_NET_RSS_IPV6:
703 	case NFP_NET_RSS_IPV6_EX:
704 		meta->hash_type = PKT_HASH_TYPE_L3;
705 		break;
706 	default:
707 		meta->hash_type = PKT_HASH_TYPE_L4;
708 		break;
709 	}
710 
711 	meta->hash = get_unaligned_be32(hash);
712 }
713 
714 static bool
nfp_nfdk_parse_meta(struct net_device * netdev,struct nfp_meta_parsed * meta,void * data,void * pkt,unsigned int pkt_len,int meta_len)715 nfp_nfdk_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
716 		    void *data, void *pkt, unsigned int pkt_len, int meta_len)
717 {
718 	u32 meta_info, vlan_info;
719 
720 	meta_info = get_unaligned_be32(data);
721 	data += 4;
722 
723 	while (meta_info) {
724 		switch (meta_info & NFP_NET_META_FIELD_MASK) {
725 		case NFP_NET_META_HASH:
726 			meta_info >>= NFP_NET_META_FIELD_SIZE;
727 			nfp_nfdk_set_hash(netdev, meta,
728 					  meta_info & NFP_NET_META_FIELD_MASK,
729 					  (__be32 *)data);
730 			data += 4;
731 			break;
732 		case NFP_NET_META_MARK:
733 			meta->mark = get_unaligned_be32(data);
734 			data += 4;
735 			break;
736 		case NFP_NET_META_VLAN:
737 			vlan_info = get_unaligned_be32(data);
738 			if (FIELD_GET(NFP_NET_META_VLAN_STRIP, vlan_info)) {
739 				meta->vlan.stripped = true;
740 				meta->vlan.tpid = FIELD_GET(NFP_NET_META_VLAN_TPID_MASK,
741 							    vlan_info);
742 				meta->vlan.tci = FIELD_GET(NFP_NET_META_VLAN_TCI_MASK,
743 							   vlan_info);
744 			}
745 			data += 4;
746 			break;
747 		case NFP_NET_META_PORTID:
748 			meta->portid = get_unaligned_be32(data);
749 			data += 4;
750 			break;
751 		case NFP_NET_META_CSUM:
752 			meta->csum_type = CHECKSUM_COMPLETE;
753 			meta->csum =
754 				(__force __wsum)__get_unaligned_cpu32(data);
755 			data += 4;
756 			break;
757 		case NFP_NET_META_RESYNC_INFO:
758 			if (nfp_net_tls_rx_resync_req(netdev, data, pkt,
759 						      pkt_len))
760 				return false;
761 			data += sizeof(struct nfp_net_tls_resync_req);
762 			break;
763 		default:
764 			return true;
765 		}
766 
767 		meta_info >>= NFP_NET_META_FIELD_SIZE;
768 	}
769 
770 	return data != pkt;
771 }
772 
773 static void
nfp_nfdk_rx_drop(const struct nfp_net_dp * dp,struct nfp_net_r_vector * r_vec,struct nfp_net_rx_ring * rx_ring,struct nfp_net_rx_buf * rxbuf,struct sk_buff * skb)774 nfp_nfdk_rx_drop(const struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
775 		 struct nfp_net_rx_ring *rx_ring, struct nfp_net_rx_buf *rxbuf,
776 		 struct sk_buff *skb)
777 {
778 	u64_stats_update_begin(&r_vec->rx_sync);
779 	r_vec->rx_drops++;
780 	/* If we have both skb and rxbuf the replacement buffer allocation
781 	 * must have failed, count this as an alloc failure.
782 	 */
783 	if (skb && rxbuf)
784 		r_vec->rx_replace_buf_alloc_fail++;
785 	u64_stats_update_end(&r_vec->rx_sync);
786 
787 	/* skb is build based on the frag, free_skb() would free the frag
788 	 * so to be able to reuse it we need an extra ref.
789 	 */
790 	if (skb && rxbuf && skb->head == rxbuf->frag)
791 		page_ref_inc(virt_to_head_page(rxbuf->frag));
792 	if (rxbuf)
793 		nfp_nfdk_rx_give_one(dp, rx_ring, rxbuf->frag, rxbuf->dma_addr);
794 	if (skb)
795 		dev_kfree_skb_any(skb);
796 }
797 
nfp_nfdk_xdp_complete(struct nfp_net_tx_ring * tx_ring)798 static bool nfp_nfdk_xdp_complete(struct nfp_net_tx_ring *tx_ring)
799 {
800 	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
801 	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
802 	struct nfp_net_rx_ring *rx_ring;
803 	u32 qcp_rd_p, done = 0;
804 	bool done_all;
805 	int todo;
806 
807 	/* Work out how many descriptors have been transmitted */
808 	qcp_rd_p = nfp_net_read_tx_cmpl(tx_ring, dp);
809 	if (qcp_rd_p == tx_ring->qcp_rd_p)
810 		return true;
811 
812 	todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);
813 
814 	done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
815 	todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);
816 
817 	rx_ring = r_vec->rx_ring;
818 	while (todo > 0) {
819 		int idx = D_IDX(tx_ring, tx_ring->rd_p + done);
820 		struct nfp_nfdk_tx_buf *txbuf;
821 		unsigned int step = 1;
822 
823 		txbuf = &tx_ring->ktxbufs[idx];
824 		if (!txbuf->raw)
825 			goto next;
826 
827 		if (NFDK_TX_BUF_INFO(txbuf->val) != NFDK_TX_BUF_INFO_SOP) {
828 			WARN_ONCE(1, "Unexpected TX buffer in XDP TX ring\n");
829 			goto next;
830 		}
831 
832 		/* Two successive txbufs are used to stash virtual and dma
833 		 * address respectively, recycle and clean them here.
834 		 */
835 		nfp_nfdk_rx_give_one(dp, rx_ring,
836 				     (void *)NFDK_TX_BUF_PTR(txbuf[0].val),
837 				     txbuf[1].dma_addr);
838 		txbuf[0].raw = 0;
839 		txbuf[1].raw = 0;
840 		step = 2;
841 
842 		u64_stats_update_begin(&r_vec->tx_sync);
843 		/* Note: tx_bytes not accumulated. */
844 		r_vec->tx_pkts++;
845 		u64_stats_update_end(&r_vec->tx_sync);
846 next:
847 		todo -= step;
848 		done += step;
849 	}
850 
851 	tx_ring->qcp_rd_p = D_IDX(tx_ring, tx_ring->qcp_rd_p + done);
852 	tx_ring->rd_p += done;
853 
854 	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
855 		  "XDP TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
856 		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
857 
858 	return done_all;
859 }
860 
861 static bool
nfp_nfdk_tx_xdp_buf(struct nfp_net_dp * dp,struct nfp_net_rx_ring * rx_ring,struct nfp_net_tx_ring * tx_ring,struct nfp_net_rx_buf * rxbuf,unsigned int dma_off,unsigned int pkt_len,bool * completed)862 nfp_nfdk_tx_xdp_buf(struct nfp_net_dp *dp, struct nfp_net_rx_ring *rx_ring,
863 		    struct nfp_net_tx_ring *tx_ring,
864 		    struct nfp_net_rx_buf *rxbuf, unsigned int dma_off,
865 		    unsigned int pkt_len, bool *completed)
866 {
867 	unsigned int dma_map_sz = dp->fl_bufsz - NFP_NET_RX_BUF_NON_DATA;
868 	unsigned int dma_len, type, cnt, dlen_type, tmp_dlen;
869 	struct nfp_nfdk_tx_buf *txbuf;
870 	struct nfp_nfdk_tx_desc *txd;
871 	unsigned int n_descs;
872 	dma_addr_t dma_addr;
873 	int wr_idx;
874 
875 	/* Reject if xdp_adjust_tail grow packet beyond DMA area */
876 	if (pkt_len + dma_off > dma_map_sz)
877 		return false;
878 
879 	/* Make sure there's still at least one block available after
880 	 * aligning to block boundary, so that the txds used below
881 	 * won't wrap around the tx_ring.
882 	 */
883 	if (unlikely(nfp_net_tx_full(tx_ring, NFDK_TX_DESC_STOP_CNT))) {
884 		if (!*completed) {
885 			nfp_nfdk_xdp_complete(tx_ring);
886 			*completed = true;
887 		}
888 
889 		if (unlikely(nfp_net_tx_full(tx_ring, NFDK_TX_DESC_STOP_CNT))) {
890 			nfp_nfdk_rx_drop(dp, rx_ring->r_vec, rx_ring, rxbuf,
891 					 NULL);
892 			return false;
893 		}
894 	}
895 
896 	/* Check if cross block boundary */
897 	n_descs = nfp_nfdk_headlen_to_segs(pkt_len);
898 	if ((round_down(tx_ring->wr_p, NFDK_TX_DESC_BLOCK_CNT) !=
899 	     round_down(tx_ring->wr_p + n_descs, NFDK_TX_DESC_BLOCK_CNT)) ||
900 	    ((u32)tx_ring->data_pending + pkt_len >
901 	     NFDK_TX_MAX_DATA_PER_BLOCK)) {
902 		unsigned int nop_slots = D_BLOCK_CPL(tx_ring->wr_p);
903 
904 		wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
905 		txd = &tx_ring->ktxds[wr_idx];
906 		memset(txd, 0,
907 		       array_size(nop_slots, sizeof(struct nfp_nfdk_tx_desc)));
908 
909 		tx_ring->data_pending = 0;
910 		tx_ring->wr_p += nop_slots;
911 		tx_ring->wr_ptr_add += nop_slots;
912 	}
913 
914 	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
915 
916 	txbuf = &tx_ring->ktxbufs[wr_idx];
917 
918 	txbuf[0].val = (unsigned long)rxbuf->frag | NFDK_TX_BUF_INFO_SOP;
919 	txbuf[1].dma_addr = rxbuf->dma_addr;
920 	/* Note: pkt len not stored */
921 
922 	dma_sync_single_for_device(dp->dev, rxbuf->dma_addr + dma_off,
923 				   pkt_len, DMA_BIDIRECTIONAL);
924 
925 	/* Build TX descriptor */
926 	txd = &tx_ring->ktxds[wr_idx];
927 	dma_len = pkt_len;
928 	dma_addr = rxbuf->dma_addr + dma_off;
929 
930 	if (dma_len <= NFDK_TX_MAX_DATA_PER_HEAD)
931 		type = NFDK_DESC_TX_TYPE_SIMPLE;
932 	else
933 		type = NFDK_DESC_TX_TYPE_GATHER;
934 
935 	/* FIELD_PREP() implicitly truncates to chunk */
936 	dma_len -= 1;
937 	dlen_type = FIELD_PREP(NFDK_DESC_TX_DMA_LEN_HEAD,
938 			       dma_len > NFDK_DESC_TX_DMA_LEN_HEAD ?
939 			       NFDK_DESC_TX_DMA_LEN_HEAD : dma_len) |
940 		    FIELD_PREP(NFDK_DESC_TX_TYPE_HEAD, type);
941 
942 	txd->dma_len_type = cpu_to_le16(dlen_type);
943 	nfp_desc_set_dma_addr_48b(txd, dma_addr);
944 
945 	tmp_dlen = dlen_type & NFDK_DESC_TX_DMA_LEN_HEAD;
946 	dma_len -= tmp_dlen;
947 	dma_addr += tmp_dlen + 1;
948 	txd++;
949 
950 	while (dma_len > 0) {
951 		dma_len -= 1;
952 		dlen_type = FIELD_PREP(NFDK_DESC_TX_DMA_LEN, dma_len);
953 		txd->dma_len_type = cpu_to_le16(dlen_type);
954 		nfp_desc_set_dma_addr_48b(txd, dma_addr);
955 
956 		dlen_type &= NFDK_DESC_TX_DMA_LEN;
957 		dma_len -= dlen_type;
958 		dma_addr += dlen_type + 1;
959 		txd++;
960 	}
961 
962 	(txd - 1)->dma_len_type = cpu_to_le16(dlen_type | NFDK_DESC_TX_EOP);
963 
964 	/* Metadata desc */
965 	txd->raw = 0;
966 	txd++;
967 
968 	cnt = txd - tx_ring->ktxds - wr_idx;
969 	tx_ring->wr_p += cnt;
970 	if (tx_ring->wr_p % NFDK_TX_DESC_BLOCK_CNT)
971 		tx_ring->data_pending += pkt_len;
972 	else
973 		tx_ring->data_pending = 0;
974 
975 	tx_ring->wr_ptr_add += cnt;
976 	return true;
977 }
978 
979 /**
980  * nfp_nfdk_rx() - receive up to @budget packets on @rx_ring
981  * @rx_ring:   RX ring to receive from
982  * @budget:    NAPI budget
983  *
984  * Note, this function is separated out from the napi poll function to
985  * more cleanly separate packet receive code from other bookkeeping
986  * functions performed in the napi poll function.
987  *
988  * Return: Number of packets received.
989  */
nfp_nfdk_rx(struct nfp_net_rx_ring * rx_ring,int budget)990 static int nfp_nfdk_rx(struct nfp_net_rx_ring *rx_ring, int budget)
991 {
992 	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
993 	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
994 	struct nfp_net_tx_ring *tx_ring;
995 	struct bpf_prog *xdp_prog;
996 	bool xdp_tx_cmpl = false;
997 	unsigned int true_bufsz;
998 	struct sk_buff *skb;
999 	int pkts_polled = 0;
1000 	struct xdp_buff xdp;
1001 	int idx;
1002 
1003 	xdp_prog = READ_ONCE(dp->xdp_prog);
1004 	true_bufsz = xdp_prog ? PAGE_SIZE : dp->fl_bufsz;
1005 	xdp_init_buff(&xdp, PAGE_SIZE - NFP_NET_RX_BUF_HEADROOM,
1006 		      &rx_ring->xdp_rxq);
1007 	tx_ring = r_vec->xdp_ring;
1008 
1009 	while (pkts_polled < budget) {
1010 		unsigned int meta_len, data_len, meta_off, pkt_len, pkt_off;
1011 		struct nfp_net_rx_buf *rxbuf;
1012 		struct nfp_net_rx_desc *rxd;
1013 		struct nfp_meta_parsed meta;
1014 		bool redir_egress = false;
1015 		struct net_device *netdev;
1016 		dma_addr_t new_dma_addr;
1017 		u32 meta_len_xdp = 0;
1018 		void *new_frag;
1019 
1020 		idx = D_IDX(rx_ring, rx_ring->rd_p);
1021 
1022 		rxd = &rx_ring->rxds[idx];
1023 		if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
1024 			break;
1025 
1026 		/* Memory barrier to ensure that we won't do other reads
1027 		 * before the DD bit.
1028 		 */
1029 		dma_rmb();
1030 
1031 		memset(&meta, 0, sizeof(meta));
1032 
1033 		rx_ring->rd_p++;
1034 		pkts_polled++;
1035 
1036 		rxbuf =	&rx_ring->rxbufs[idx];
1037 		/*         < meta_len >
1038 		 *  <-- [rx_offset] -->
1039 		 *  ---------------------------------------------------------
1040 		 * | [XX] |  metadata  |             packet           | XXXX |
1041 		 *  ---------------------------------------------------------
1042 		 *         <---------------- data_len --------------->
1043 		 *
1044 		 * The rx_offset is fixed for all packets, the meta_len can vary
1045 		 * on a packet by packet basis. If rx_offset is set to zero
1046 		 * (_RX_OFFSET_DYNAMIC) metadata starts at the beginning of the
1047 		 * buffer and is immediately followed by the packet (no [XX]).
1048 		 */
1049 		meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
1050 		data_len = le16_to_cpu(rxd->rxd.data_len);
1051 		pkt_len = data_len - meta_len;
1052 
1053 		pkt_off = NFP_NET_RX_BUF_HEADROOM + dp->rx_dma_off;
1054 		if (dp->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
1055 			pkt_off += meta_len;
1056 		else
1057 			pkt_off += dp->rx_offset;
1058 		meta_off = pkt_off - meta_len;
1059 
1060 		/* Stats update */
1061 		u64_stats_update_begin(&r_vec->rx_sync);
1062 		r_vec->rx_pkts++;
1063 		r_vec->rx_bytes += pkt_len;
1064 		u64_stats_update_end(&r_vec->rx_sync);
1065 
1066 		if (unlikely(meta_len > NFP_NET_MAX_PREPEND ||
1067 			     (dp->rx_offset && meta_len > dp->rx_offset))) {
1068 			nn_dp_warn(dp, "oversized RX packet metadata %u\n",
1069 				   meta_len);
1070 			nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1071 			continue;
1072 		}
1073 
1074 		nfp_net_dma_sync_cpu_rx(dp, rxbuf->dma_addr + meta_off,
1075 					data_len);
1076 
1077 		if (meta_len) {
1078 			if (unlikely(nfp_nfdk_parse_meta(dp->netdev, &meta,
1079 							 rxbuf->frag + meta_off,
1080 							 rxbuf->frag + pkt_off,
1081 							 pkt_len, meta_len))) {
1082 				nn_dp_warn(dp, "invalid RX packet metadata\n");
1083 				nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf,
1084 						 NULL);
1085 				continue;
1086 			}
1087 		}
1088 
1089 		if (xdp_prog && !meta.portid) {
1090 			void *orig_data = rxbuf->frag + pkt_off;
1091 			unsigned int dma_off;
1092 			int act;
1093 
1094 			xdp_prepare_buff(&xdp,
1095 					 rxbuf->frag + NFP_NET_RX_BUF_HEADROOM,
1096 					 pkt_off - NFP_NET_RX_BUF_HEADROOM,
1097 					 pkt_len, true);
1098 
1099 			act = bpf_prog_run_xdp(xdp_prog, &xdp);
1100 
1101 			pkt_len = xdp.data_end - xdp.data;
1102 			pkt_off += xdp.data - orig_data;
1103 
1104 			switch (act) {
1105 			case XDP_PASS:
1106 				meta_len_xdp = xdp.data - xdp.data_meta;
1107 				break;
1108 			case XDP_TX:
1109 				dma_off = pkt_off - NFP_NET_RX_BUF_HEADROOM;
1110 				if (unlikely(!nfp_nfdk_tx_xdp_buf(dp, rx_ring,
1111 								  tx_ring,
1112 								  rxbuf,
1113 								  dma_off,
1114 								  pkt_len,
1115 								  &xdp_tx_cmpl)))
1116 					trace_xdp_exception(dp->netdev,
1117 							    xdp_prog, act);
1118 				continue;
1119 			default:
1120 				bpf_warn_invalid_xdp_action(dp->netdev, xdp_prog, act);
1121 				fallthrough;
1122 			case XDP_ABORTED:
1123 				trace_xdp_exception(dp->netdev, xdp_prog, act);
1124 				fallthrough;
1125 			case XDP_DROP:
1126 				nfp_nfdk_rx_give_one(dp, rx_ring, rxbuf->frag,
1127 						     rxbuf->dma_addr);
1128 				continue;
1129 			}
1130 		}
1131 
1132 		if (likely(!meta.portid)) {
1133 			netdev = dp->netdev;
1134 		} else if (meta.portid == NFP_META_PORT_ID_CTRL) {
1135 			struct nfp_net *nn = netdev_priv(dp->netdev);
1136 
1137 			nfp_app_ctrl_rx_raw(nn->app, rxbuf->frag + pkt_off,
1138 					    pkt_len);
1139 			nfp_nfdk_rx_give_one(dp, rx_ring, rxbuf->frag,
1140 					     rxbuf->dma_addr);
1141 			continue;
1142 		} else {
1143 			struct nfp_net *nn;
1144 
1145 			nn = netdev_priv(dp->netdev);
1146 			netdev = nfp_app_dev_get(nn->app, meta.portid,
1147 						 &redir_egress);
1148 			if (unlikely(!netdev)) {
1149 				nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf,
1150 						 NULL);
1151 				continue;
1152 			}
1153 
1154 			if (nfp_netdev_is_nfp_repr(netdev))
1155 				nfp_repr_inc_rx_stats(netdev, pkt_len);
1156 		}
1157 
1158 		skb = build_skb(rxbuf->frag, true_bufsz);
1159 		if (unlikely(!skb)) {
1160 			nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1161 			continue;
1162 		}
1163 		new_frag = nfp_nfdk_napi_alloc_one(dp, &new_dma_addr);
1164 		if (unlikely(!new_frag)) {
1165 			nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf, skb);
1166 			continue;
1167 		}
1168 
1169 		nfp_net_dma_unmap_rx(dp, rxbuf->dma_addr);
1170 
1171 		nfp_nfdk_rx_give_one(dp, rx_ring, new_frag, new_dma_addr);
1172 
1173 		skb_reserve(skb, pkt_off);
1174 		skb_put(skb, pkt_len);
1175 
1176 		skb->mark = meta.mark;
1177 		skb_set_hash(skb, meta.hash, meta.hash_type);
1178 
1179 		skb_record_rx_queue(skb, rx_ring->idx);
1180 		skb->protocol = eth_type_trans(skb, netdev);
1181 
1182 		nfp_nfdk_rx_csum(dp, r_vec, rxd, &meta, skb);
1183 
1184 		if (unlikely(!nfp_net_vlan_strip(skb, rxd, &meta))) {
1185 			nfp_nfdk_rx_drop(dp, r_vec, rx_ring, NULL, skb);
1186 			continue;
1187 		}
1188 
1189 		if (meta_len_xdp)
1190 			skb_metadata_set(skb, meta_len_xdp);
1191 
1192 		if (likely(!redir_egress)) {
1193 			napi_gro_receive(&rx_ring->r_vec->napi, skb);
1194 		} else {
1195 			skb->dev = netdev;
1196 			skb_reset_network_header(skb);
1197 			__skb_push(skb, ETH_HLEN);
1198 			dev_queue_xmit(skb);
1199 		}
1200 	}
1201 
1202 	if (xdp_prog) {
1203 		if (tx_ring->wr_ptr_add)
1204 			nfp_net_tx_xmit_more_flush(tx_ring);
1205 		else if (unlikely(tx_ring->wr_p != tx_ring->rd_p) &&
1206 			 !xdp_tx_cmpl)
1207 			if (!nfp_nfdk_xdp_complete(tx_ring))
1208 				pkts_polled = budget;
1209 	}
1210 
1211 	return pkts_polled;
1212 }
1213 
1214 /**
1215  * nfp_nfdk_poll() - napi poll function
1216  * @napi:    NAPI structure
1217  * @budget:  NAPI budget
1218  *
1219  * Return: number of packets polled.
1220  */
nfp_nfdk_poll(struct napi_struct * napi,int budget)1221 int nfp_nfdk_poll(struct napi_struct *napi, int budget)
1222 {
1223 	struct nfp_net_r_vector *r_vec =
1224 		container_of(napi, struct nfp_net_r_vector, napi);
1225 	unsigned int pkts_polled = 0;
1226 
1227 	if (r_vec->tx_ring)
1228 		nfp_nfdk_tx_complete(r_vec->tx_ring, budget);
1229 	if (r_vec->rx_ring)
1230 		pkts_polled = nfp_nfdk_rx(r_vec->rx_ring, budget);
1231 
1232 	if (pkts_polled < budget)
1233 		if (napi_complete_done(napi, pkts_polled))
1234 			nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
1235 
1236 	if (r_vec->nfp_net->rx_coalesce_adapt_on && r_vec->rx_ring) {
1237 		struct dim_sample dim_sample = {};
1238 		unsigned int start;
1239 		u64 pkts, bytes;
1240 
1241 		do {
1242 			start = u64_stats_fetch_begin(&r_vec->rx_sync);
1243 			pkts = r_vec->rx_pkts;
1244 			bytes = r_vec->rx_bytes;
1245 		} while (u64_stats_fetch_retry(&r_vec->rx_sync, start));
1246 
1247 		dim_update_sample(r_vec->event_ctr, pkts, bytes, &dim_sample);
1248 		net_dim(&r_vec->rx_dim, dim_sample);
1249 	}
1250 
1251 	if (r_vec->nfp_net->tx_coalesce_adapt_on && r_vec->tx_ring) {
1252 		struct dim_sample dim_sample = {};
1253 		unsigned int start;
1254 		u64 pkts, bytes;
1255 
1256 		do {
1257 			start = u64_stats_fetch_begin(&r_vec->tx_sync);
1258 			pkts = r_vec->tx_pkts;
1259 			bytes = r_vec->tx_bytes;
1260 		} while (u64_stats_fetch_retry(&r_vec->tx_sync, start));
1261 
1262 		dim_update_sample(r_vec->event_ctr, pkts, bytes, &dim_sample);
1263 		net_dim(&r_vec->tx_dim, dim_sample);
1264 	}
1265 
1266 	return pkts_polled;
1267 }
1268 
1269 /* Control device data path
1270  */
1271 
1272 bool
nfp_nfdk_ctrl_tx_one(struct nfp_net * nn,struct nfp_net_r_vector * r_vec,struct sk_buff * skb,bool old)1273 nfp_nfdk_ctrl_tx_one(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
1274 		     struct sk_buff *skb, bool old)
1275 {
1276 	u32 cnt, tmp_dlen, dlen_type = 0;
1277 	struct nfp_net_tx_ring *tx_ring;
1278 	struct nfp_nfdk_tx_buf *txbuf;
1279 	struct nfp_nfdk_tx_desc *txd;
1280 	unsigned int dma_len, type;
1281 	struct nfp_net_dp *dp;
1282 	dma_addr_t dma_addr;
1283 	u64 metadata = 0;
1284 	int wr_idx;
1285 
1286 	dp = &r_vec->nfp_net->dp;
1287 	tx_ring = r_vec->tx_ring;
1288 
1289 	if (WARN_ON_ONCE(skb_shinfo(skb)->nr_frags)) {
1290 		nn_dp_warn(dp, "Driver's CTRL TX does not implement gather\n");
1291 		goto err_free;
1292 	}
1293 
1294 	/* Don't bother counting frags, assume the worst */
1295 	if (unlikely(nfp_net_tx_full(tx_ring, NFDK_TX_DESC_STOP_CNT))) {
1296 		u64_stats_update_begin(&r_vec->tx_sync);
1297 		r_vec->tx_busy++;
1298 		u64_stats_update_end(&r_vec->tx_sync);
1299 		if (!old)
1300 			__skb_queue_tail(&r_vec->queue, skb);
1301 		else
1302 			__skb_queue_head(&r_vec->queue, skb);
1303 		return NETDEV_TX_BUSY;
1304 	}
1305 
1306 	if (nfp_app_ctrl_has_meta(nn->app)) {
1307 		if (unlikely(skb_headroom(skb) < 8)) {
1308 			nn_dp_warn(dp, "CTRL TX on skb without headroom\n");
1309 			goto err_free;
1310 		}
1311 		metadata = NFDK_DESC_TX_CHAIN_META;
1312 		put_unaligned_be32(NFP_META_PORT_ID_CTRL, skb_push(skb, 4));
1313 		put_unaligned_be32(FIELD_PREP(NFDK_META_LEN, 8) |
1314 				   FIELD_PREP(NFDK_META_FIELDS,
1315 					      NFP_NET_META_PORTID),
1316 				   skb_push(skb, 4));
1317 	}
1318 
1319 	if (nfp_nfdk_tx_maybe_close_block(tx_ring, skb))
1320 		goto err_free;
1321 
1322 	/* DMA map all */
1323 	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);
1324 	txd = &tx_ring->ktxds[wr_idx];
1325 	txbuf = &tx_ring->ktxbufs[wr_idx];
1326 
1327 	dma_len = skb_headlen(skb);
1328 	if (dma_len <= NFDK_TX_MAX_DATA_PER_HEAD)
1329 		type = NFDK_DESC_TX_TYPE_SIMPLE;
1330 	else
1331 		type = NFDK_DESC_TX_TYPE_GATHER;
1332 
1333 	dma_addr = dma_map_single(dp->dev, skb->data, dma_len, DMA_TO_DEVICE);
1334 	if (dma_mapping_error(dp->dev, dma_addr))
1335 		goto err_warn_dma;
1336 
1337 	txbuf->skb = skb;
1338 	txbuf++;
1339 
1340 	txbuf->dma_addr = dma_addr;
1341 	txbuf++;
1342 
1343 	dma_len -= 1;
1344 	dlen_type = FIELD_PREP(NFDK_DESC_TX_DMA_LEN_HEAD,
1345 			       dma_len > NFDK_DESC_TX_DMA_LEN_HEAD ?
1346 			       NFDK_DESC_TX_DMA_LEN_HEAD : dma_len) |
1347 		    FIELD_PREP(NFDK_DESC_TX_TYPE_HEAD, type);
1348 
1349 	txd->dma_len_type = cpu_to_le16(dlen_type);
1350 	nfp_desc_set_dma_addr_48b(txd, dma_addr);
1351 
1352 	tmp_dlen = dlen_type & NFDK_DESC_TX_DMA_LEN_HEAD;
1353 	dma_len -= tmp_dlen;
1354 	dma_addr += tmp_dlen + 1;
1355 	txd++;
1356 
1357 	while (dma_len > 0) {
1358 		dma_len -= 1;
1359 		dlen_type = FIELD_PREP(NFDK_DESC_TX_DMA_LEN, dma_len);
1360 		txd->dma_len_type = cpu_to_le16(dlen_type);
1361 		nfp_desc_set_dma_addr_48b(txd, dma_addr);
1362 
1363 		dlen_type &= NFDK_DESC_TX_DMA_LEN;
1364 		dma_len -= dlen_type;
1365 		dma_addr += dlen_type + 1;
1366 		txd++;
1367 	}
1368 
1369 	(txd - 1)->dma_len_type = cpu_to_le16(dlen_type | NFDK_DESC_TX_EOP);
1370 
1371 	/* Metadata desc */
1372 	txd->raw = cpu_to_le64(metadata);
1373 	txd++;
1374 
1375 	cnt = txd - tx_ring->ktxds - wr_idx;
1376 	if (unlikely(round_down(wr_idx, NFDK_TX_DESC_BLOCK_CNT) !=
1377 		     round_down(wr_idx + cnt - 1, NFDK_TX_DESC_BLOCK_CNT)))
1378 		goto err_warn_overflow;
1379 
1380 	tx_ring->wr_p += cnt;
1381 	if (tx_ring->wr_p % NFDK_TX_DESC_BLOCK_CNT)
1382 		tx_ring->data_pending += skb->len;
1383 	else
1384 		tx_ring->data_pending = 0;
1385 
1386 	tx_ring->wr_ptr_add += cnt;
1387 	nfp_net_tx_xmit_more_flush(tx_ring);
1388 
1389 	return NETDEV_TX_OK;
1390 
1391 err_warn_overflow:
1392 	WARN_ONCE(1, "unable to fit packet into a descriptor wr_idx:%d head:%d frags:%d cnt:%d",
1393 		  wr_idx, skb_headlen(skb), 0, cnt);
1394 	txbuf--;
1395 	dma_unmap_single(dp->dev, txbuf->dma_addr,
1396 			 skb_headlen(skb), DMA_TO_DEVICE);
1397 	txbuf->raw = 0;
1398 err_warn_dma:
1399 	nn_dp_warn(dp, "Failed to map DMA TX buffer\n");
1400 err_free:
1401 	u64_stats_update_begin(&r_vec->tx_sync);
1402 	r_vec->tx_errors++;
1403 	u64_stats_update_end(&r_vec->tx_sync);
1404 	dev_kfree_skb_any(skb);
1405 	return NETDEV_TX_OK;
1406 }
1407 
__nfp_ctrl_tx_queued(struct nfp_net_r_vector * r_vec)1408 static void __nfp_ctrl_tx_queued(struct nfp_net_r_vector *r_vec)
1409 {
1410 	struct sk_buff *skb;
1411 
1412 	while ((skb = __skb_dequeue(&r_vec->queue)))
1413 		if (nfp_nfdk_ctrl_tx_one(r_vec->nfp_net, r_vec, skb, true))
1414 			return;
1415 }
1416 
1417 static bool
nfp_ctrl_meta_ok(struct nfp_net * nn,void * data,unsigned int meta_len)1418 nfp_ctrl_meta_ok(struct nfp_net *nn, void *data, unsigned int meta_len)
1419 {
1420 	u32 meta_type, meta_tag;
1421 
1422 	if (!nfp_app_ctrl_has_meta(nn->app))
1423 		return !meta_len;
1424 
1425 	if (meta_len != 8)
1426 		return false;
1427 
1428 	meta_type = get_unaligned_be32(data);
1429 	meta_tag = get_unaligned_be32(data + 4);
1430 
1431 	return (meta_type == NFP_NET_META_PORTID &&
1432 		meta_tag == NFP_META_PORT_ID_CTRL);
1433 }
1434 
1435 static bool
nfp_ctrl_rx_one(struct nfp_net * nn,struct nfp_net_dp * dp,struct nfp_net_r_vector * r_vec,struct nfp_net_rx_ring * rx_ring)1436 nfp_ctrl_rx_one(struct nfp_net *nn, struct nfp_net_dp *dp,
1437 		struct nfp_net_r_vector *r_vec, struct nfp_net_rx_ring *rx_ring)
1438 {
1439 	unsigned int meta_len, data_len, meta_off, pkt_len, pkt_off;
1440 	struct nfp_net_rx_buf *rxbuf;
1441 	struct nfp_net_rx_desc *rxd;
1442 	dma_addr_t new_dma_addr;
1443 	struct sk_buff *skb;
1444 	void *new_frag;
1445 	int idx;
1446 
1447 	idx = D_IDX(rx_ring, rx_ring->rd_p);
1448 
1449 	rxd = &rx_ring->rxds[idx];
1450 	if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
1451 		return false;
1452 
1453 	/* Memory barrier to ensure that we won't do other reads
1454 	 * before the DD bit.
1455 	 */
1456 	dma_rmb();
1457 
1458 	rx_ring->rd_p++;
1459 
1460 	rxbuf =	&rx_ring->rxbufs[idx];
1461 	meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
1462 	data_len = le16_to_cpu(rxd->rxd.data_len);
1463 	pkt_len = data_len - meta_len;
1464 
1465 	pkt_off = NFP_NET_RX_BUF_HEADROOM + dp->rx_dma_off;
1466 	if (dp->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
1467 		pkt_off += meta_len;
1468 	else
1469 		pkt_off += dp->rx_offset;
1470 	meta_off = pkt_off - meta_len;
1471 
1472 	/* Stats update */
1473 	u64_stats_update_begin(&r_vec->rx_sync);
1474 	r_vec->rx_pkts++;
1475 	r_vec->rx_bytes += pkt_len;
1476 	u64_stats_update_end(&r_vec->rx_sync);
1477 
1478 	nfp_net_dma_sync_cpu_rx(dp, rxbuf->dma_addr + meta_off,	data_len);
1479 
1480 	if (unlikely(!nfp_ctrl_meta_ok(nn, rxbuf->frag + meta_off, meta_len))) {
1481 		nn_dp_warn(dp, "incorrect metadata for ctrl packet (%d)\n",
1482 			   meta_len);
1483 		nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1484 		return true;
1485 	}
1486 
1487 	skb = build_skb(rxbuf->frag, dp->fl_bufsz);
1488 	if (unlikely(!skb)) {
1489 		nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
1490 		return true;
1491 	}
1492 	new_frag = nfp_nfdk_napi_alloc_one(dp, &new_dma_addr);
1493 	if (unlikely(!new_frag)) {
1494 		nfp_nfdk_rx_drop(dp, r_vec, rx_ring, rxbuf, skb);
1495 		return true;
1496 	}
1497 
1498 	nfp_net_dma_unmap_rx(dp, rxbuf->dma_addr);
1499 
1500 	nfp_nfdk_rx_give_one(dp, rx_ring, new_frag, new_dma_addr);
1501 
1502 	skb_reserve(skb, pkt_off);
1503 	skb_put(skb, pkt_len);
1504 
1505 	nfp_app_ctrl_rx(nn->app, skb);
1506 
1507 	return true;
1508 }
1509 
nfp_ctrl_rx(struct nfp_net_r_vector * r_vec)1510 static bool nfp_ctrl_rx(struct nfp_net_r_vector *r_vec)
1511 {
1512 	struct nfp_net_rx_ring *rx_ring = r_vec->rx_ring;
1513 	struct nfp_net *nn = r_vec->nfp_net;
1514 	struct nfp_net_dp *dp = &nn->dp;
1515 	unsigned int budget = 512;
1516 
1517 	while (nfp_ctrl_rx_one(nn, dp, r_vec, rx_ring) && budget--)
1518 		continue;
1519 
1520 	return budget;
1521 }
1522 
nfp_nfdk_ctrl_poll(struct tasklet_struct * t)1523 void nfp_nfdk_ctrl_poll(struct tasklet_struct *t)
1524 {
1525 	struct nfp_net_r_vector *r_vec = from_tasklet(r_vec, t, tasklet);
1526 
1527 	spin_lock(&r_vec->lock);
1528 	nfp_nfdk_tx_complete(r_vec->tx_ring, 0);
1529 	__nfp_ctrl_tx_queued(r_vec);
1530 	spin_unlock(&r_vec->lock);
1531 
1532 	if (nfp_ctrl_rx(r_vec)) {
1533 		nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
1534 	} else {
1535 		tasklet_schedule(&r_vec->tasklet);
1536 		nn_dp_warn(&r_vec->nfp_net->dp,
1537 			   "control message budget exceeded!\n");
1538 	}
1539 }
1540