dp.c 35.0 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394
// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (C) 2015-2019 Netronome Systems, Inc. */

#include <linux/bpf_trace.h>
#include <linux/netdevice.h>

#include "../nfp_app.h"
#include "../nfp_net.h"
#include "../nfp_net_dp.h"
#include "../nfp_net_xsk.h"
#include "../crypto/crypto.h"
#include "../crypto/fw.h"
#include "nfd3.h"

/* Transmit processing
 *
 * One queue controller peripheral queue is used for transmit.  The
 * driver en-queues packets for transmit by advancing the write
 * pointer.  The device indicates that packets have transmitted by
 * advancing the read pointer.  The driver maintains a local copy of
 * the read and write pointer in @struct nfp_net_tx_ring.  The driver
 * keeps @wr_p in sync with the queue controller write pointer and can
 * determine how many packets have been transmitted by comparing its
 * copy of the read pointer @rd_p with the read pointer maintained by
 * the queue controller peripheral.
 */

/* Wrappers for deciding when to stop and restart TX queues */
static int nfp_nfd3_tx_ring_should_wake(struct nfp_net_tx_ring *tx_ring)
{
	return !nfp_net_tx_full(tx_ring, MAX_SKB_FRAGS * 4);
}

static int nfp_nfd3_tx_ring_should_stop(struct nfp_net_tx_ring *tx_ring)
{
	return nfp_net_tx_full(tx_ring, MAX_SKB_FRAGS + 1);
}

/**
 * nfp_nfd3_tx_ring_stop() - stop tx ring
 * @nd_q:    netdev queue
 * @tx_ring: driver tx queue structure
 *
 * Safely stop TX ring.  Remember that while we are running .start_xmit()
 * someone else may be cleaning the TX ring completions so we need to be
 * extra careful here.
 */
static void
nfp_nfd3_tx_ring_stop(struct netdev_queue *nd_q,
		      struct nfp_net_tx_ring *tx_ring)
{
	netif_tx_stop_queue(nd_q);

	/* We can race with the TX completion out of NAPI so recheck */
	smp_mb();
	if (unlikely(nfp_nfd3_tx_ring_should_wake(tx_ring)))
		netif_tx_start_queue(nd_q);
}

/**
 * nfp_nfd3_tx_tso() - Set up Tx descriptor for LSO
 * @r_vec: per-ring structure
 * @txbuf: Pointer to driver soft TX descriptor
 * @txd: Pointer to HW TX descriptor
 * @skb: Pointer to SKB
 * @md_bytes: Prepend length
 *
 * Set up Tx descriptor for LSO, do nothing for non-LSO skbs.
 * Return error on packet header greater than maximum supported LSO header size.
 */
static void
nfp_nfd3_tx_tso(struct nfp_net_r_vector *r_vec, struct nfp_nfd3_tx_buf *txbuf,
		struct nfp_nfd3_tx_desc *txd, struct sk_buff *skb, u32 md_bytes)
{
	u32 l3_offset, l4_offset, hdrlen;
	u16 mss;

	if (!skb_is_gso(skb))
		return;

	if (!skb->encapsulation) {
		l3_offset = skb_network_offset(skb);
		l4_offset = skb_transport_offset(skb);
		hdrlen = skb_transport_offset(skb) + tcp_hdrlen(skb);
	} else {
		l3_offset = skb_inner_network_offset(skb);
		l4_offset = skb_inner_transport_offset(skb);
		hdrlen = skb_inner_transport_header(skb) - skb->data +
			inner_tcp_hdrlen(skb);
	}

	txbuf->pkt_cnt = skb_shinfo(skb)->gso_segs;
	txbuf->real_len += hdrlen * (txbuf->pkt_cnt - 1);

	mss = skb_shinfo(skb)->gso_size & NFD3_DESC_TX_MSS_MASK;
	txd->l3_offset = l3_offset - md_bytes;
	txd->l4_offset = l4_offset - md_bytes;
	txd->lso_hdrlen = hdrlen - md_bytes;
	txd->mss = cpu_to_le16(mss);
	txd->flags |= NFD3_DESC_TX_LSO;

	u64_stats_update_begin(&r_vec->tx_sync);
	r_vec->tx_lso++;
	u64_stats_update_end(&r_vec->tx_sync);
}

/**
 * nfp_nfd3_tx_csum() - Set TX CSUM offload flags in TX descriptor
 * @dp:  NFP Net data path struct
 * @r_vec: per-ring structure
 * @txbuf: Pointer to driver soft TX descriptor
 * @txd: Pointer to TX descriptor
 * @skb: Pointer to SKB
 *
 * This function sets the TX checksum flags in the TX descriptor based
 * on the configuration and the protocol of the packet to be transmitted.
 */
static void
nfp_nfd3_tx_csum(struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
		 struct nfp_nfd3_tx_buf *txbuf, struct nfp_nfd3_tx_desc *txd,
		 struct sk_buff *skb)
{
	struct ipv6hdr *ipv6h;
	struct iphdr *iph;
	u8 l4_hdr;

	if (!(dp->ctrl & NFP_NET_CFG_CTRL_TXCSUM))
		return;

	if (skb->ip_summed != CHECKSUM_PARTIAL)
		return;

	txd->flags |= NFD3_DESC_TX_CSUM;
	if (skb->encapsulation)
		txd->flags |= NFD3_DESC_TX_ENCAP;

	iph = skb->encapsulation ? inner_ip_hdr(skb) : ip_hdr(skb);
	ipv6h = skb->encapsulation ? inner_ipv6_hdr(skb) : ipv6_hdr(skb);

	if (iph->version == 4) {
		txd->flags |= NFD3_DESC_TX_IP4_CSUM;
		l4_hdr = iph->protocol;
	} else if (ipv6h->version == 6) {
		l4_hdr = ipv6h->nexthdr;
	} else {
		nn_dp_warn(dp, "partial checksum but ipv=%x!\n", iph->version);
		return;
	}

	switch (l4_hdr) {
	case IPPROTO_TCP:
		txd->flags |= NFD3_DESC_TX_TCP_CSUM;
		break;
	case IPPROTO_UDP:
		txd->flags |= NFD3_DESC_TX_UDP_CSUM;
		break;
	default:
		nn_dp_warn(dp, "partial checksum but l4 proto=%x!\n", l4_hdr);
		return;
	}

	u64_stats_update_begin(&r_vec->tx_sync);
	if (skb->encapsulation)
		r_vec->hw_csum_tx_inner += txbuf->pkt_cnt;
	else
		r_vec->hw_csum_tx += txbuf->pkt_cnt;
	u64_stats_update_end(&r_vec->tx_sync);
}

static int nfp_nfd3_prep_tx_meta(struct sk_buff *skb, u64 tls_handle)
{
	struct metadata_dst *md_dst = skb_metadata_dst(skb);
	unsigned char *data;
	u32 meta_id = 0;
	int md_bytes;

	if (likely(!md_dst && !tls_handle))
		return 0;
	if (unlikely(md_dst && md_dst->type != METADATA_HW_PORT_MUX)) {
		if (!tls_handle)
			return 0;
		md_dst = NULL;
	}

	md_bytes = 4 + !!md_dst * 4 + !!tls_handle * 8;

	if (unlikely(skb_cow_head(skb, md_bytes)))
		return -ENOMEM;

	meta_id = 0;
	data = skb_push(skb, md_bytes) + md_bytes;
	if (md_dst) {
		data -= 4;
		put_unaligned_be32(md_dst->u.port_info.port_id, data);
		meta_id = NFP_NET_META_PORTID;
	}
	if (tls_handle) {
		/* conn handle is opaque, we just use u64 to be able to quickly
		 * compare it to zero
		 */
		data -= 8;
		memcpy(data, &tls_handle, sizeof(tls_handle));
		meta_id <<= NFP_NET_META_FIELD_SIZE;
		meta_id |= NFP_NET_META_CONN_HANDLE;
	}

	data -= 4;
	put_unaligned_be32(meta_id, data);

	return md_bytes;
}

/**
 * nfp_nfd3_tx() - Main transmit entry point
 * @skb:    SKB to transmit
 * @netdev: netdev structure
 *
 * Return: NETDEV_TX_OK on success.
 */
netdev_tx_t nfp_nfd3_tx(struct sk_buff *skb, struct net_device *netdev)
{
	struct nfp_net *nn = netdev_priv(netdev);
	int f, nr_frags, wr_idx, md_bytes;
	struct nfp_net_tx_ring *tx_ring;
	struct nfp_net_r_vector *r_vec;
	struct nfp_nfd3_tx_buf *txbuf;
	struct nfp_nfd3_tx_desc *txd;
	struct netdev_queue *nd_q;
	const skb_frag_t *frag;
	struct nfp_net_dp *dp;
	dma_addr_t dma_addr;
	unsigned int fsize;
	u64 tls_handle = 0;
	u16 qidx;

	dp = &nn->dp;
	qidx = skb_get_queue_mapping(skb);
	tx_ring = &dp->tx_rings[qidx];
	r_vec = tx_ring->r_vec;

	nr_frags = skb_shinfo(skb)->nr_frags;

	if (unlikely(nfp_net_tx_full(tx_ring, nr_frags + 1))) {
		nn_dp_warn(dp, "TX ring %d busy. wrp=%u rdp=%u\n",
			   qidx, tx_ring->wr_p, tx_ring->rd_p);
		nd_q = netdev_get_tx_queue(dp->netdev, qidx);
		netif_tx_stop_queue(nd_q);
		nfp_net_tx_xmit_more_flush(tx_ring);
		u64_stats_update_begin(&r_vec->tx_sync);
		r_vec->tx_busy++;
		u64_stats_update_end(&r_vec->tx_sync);
		return NETDEV_TX_BUSY;
	}

	skb = nfp_net_tls_tx(dp, r_vec, skb, &tls_handle, &nr_frags);
	if (unlikely(!skb)) {
		nfp_net_tx_xmit_more_flush(tx_ring);
		return NETDEV_TX_OK;
	}

	md_bytes = nfp_nfd3_prep_tx_meta(skb, tls_handle);
	if (unlikely(md_bytes < 0))
		goto err_flush;

	/* Start with the head skbuf */
	dma_addr = dma_map_single(dp->dev, skb->data, skb_headlen(skb),
				  DMA_TO_DEVICE);
	if (dma_mapping_error(dp->dev, dma_addr))
		goto err_dma_err;

	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);

	/* Stash the soft descriptor of the head then initialize it */
	txbuf = &tx_ring->txbufs[wr_idx];
	txbuf->skb = skb;
	txbuf->dma_addr = dma_addr;
	txbuf->fidx = -1;
	txbuf->pkt_cnt = 1;
	txbuf->real_len = skb->len;

	/* Build TX descriptor */
	txd = &tx_ring->txds[wr_idx];
	txd->offset_eop = (nr_frags ? 0 : NFD3_DESC_TX_EOP) | md_bytes;
	txd->dma_len = cpu_to_le16(skb_headlen(skb));
	nfp_desc_set_dma_addr(txd, dma_addr);
	txd->data_len = cpu_to_le16(skb->len);

	txd->flags = 0;
	txd->mss = 0;
	txd->lso_hdrlen = 0;

	/* Do not reorder - tso may adjust pkt cnt, vlan may override fields */
	nfp_nfd3_tx_tso(r_vec, txbuf, txd, skb, md_bytes);
	nfp_nfd3_tx_csum(dp, r_vec, txbuf, txd, skb);
	if (skb_vlan_tag_present(skb) && dp->ctrl & NFP_NET_CFG_CTRL_TXVLAN) {
		txd->flags |= NFD3_DESC_TX_VLAN;
		txd->vlan = cpu_to_le16(skb_vlan_tag_get(skb));
	}

	/* Gather DMA */
	if (nr_frags > 0) {
		__le64 second_half;

		/* all descs must match except for in addr, length and eop */
		second_half = txd->vals8[1];

		for (f = 0; f < nr_frags; f++) {
			frag = &skb_shinfo(skb)->frags[f];
			fsize = skb_frag_size(frag);

			dma_addr = skb_frag_dma_map(dp->dev, frag, 0,
						    fsize, DMA_TO_DEVICE);
			if (dma_mapping_error(dp->dev, dma_addr))
				goto err_unmap;

			wr_idx = D_IDX(tx_ring, wr_idx + 1);
			tx_ring->txbufs[wr_idx].skb = skb;
			tx_ring->txbufs[wr_idx].dma_addr = dma_addr;
			tx_ring->txbufs[wr_idx].fidx = f;

			txd = &tx_ring->txds[wr_idx];
			txd->dma_len = cpu_to_le16(fsize);
			nfp_desc_set_dma_addr(txd, dma_addr);
			txd->offset_eop = md_bytes |
				((f == nr_frags - 1) ? NFD3_DESC_TX_EOP : 0);
			txd->vals8[1] = second_half;
		}

		u64_stats_update_begin(&r_vec->tx_sync);
		r_vec->tx_gather++;
		u64_stats_update_end(&r_vec->tx_sync);
	}

	skb_tx_timestamp(skb);

	nd_q = netdev_get_tx_queue(dp->netdev, tx_ring->idx);

	tx_ring->wr_p += nr_frags + 1;
	if (nfp_nfd3_tx_ring_should_stop(tx_ring))
		nfp_nfd3_tx_ring_stop(nd_q, tx_ring);

	tx_ring->wr_ptr_add += nr_frags + 1;
	if (__netdev_tx_sent_queue(nd_q, txbuf->real_len, netdev_xmit_more()))
		nfp_net_tx_xmit_more_flush(tx_ring);

	return NETDEV_TX_OK;

err_unmap:
	while (--f >= 0) {
		frag = &skb_shinfo(skb)->frags[f];
		dma_unmap_page(dp->dev, tx_ring->txbufs[wr_idx].dma_addr,
			       skb_frag_size(frag), DMA_TO_DEVICE);
		tx_ring->txbufs[wr_idx].skb = NULL;
		tx_ring->txbufs[wr_idx].dma_addr = 0;
		tx_ring->txbufs[wr_idx].fidx = -2;
		wr_idx = wr_idx - 1;
		if (wr_idx < 0)
			wr_idx += tx_ring->cnt;
	}
	dma_unmap_single(dp->dev, tx_ring->txbufs[wr_idx].dma_addr,
			 skb_headlen(skb), DMA_TO_DEVICE);
	tx_ring->txbufs[wr_idx].skb = NULL;
	tx_ring->txbufs[wr_idx].dma_addr = 0;
	tx_ring->txbufs[wr_idx].fidx = -2;
err_dma_err:
	nn_dp_warn(dp, "Failed to map DMA TX buffer\n");
err_flush:
	nfp_net_tx_xmit_more_flush(tx_ring);
	u64_stats_update_begin(&r_vec->tx_sync);
	r_vec->tx_errors++;
	u64_stats_update_end(&r_vec->tx_sync);
	nfp_net_tls_tx_undo(skb, tls_handle);
	dev_kfree_skb_any(skb);
	return NETDEV_TX_OK;
}

/**
 * nfp_nfd3_tx_complete() - Handled completed TX packets
 * @tx_ring:	TX ring structure
 * @budget:	NAPI budget (only used as bool to determine if in NAPI context)
 */
void nfp_nfd3_tx_complete(struct nfp_net_tx_ring *tx_ring, int budget)
{
	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
	u32 done_pkts = 0, done_bytes = 0;
	struct netdev_queue *nd_q;
	u32 qcp_rd_p;
	int todo;

	if (tx_ring->wr_p == tx_ring->rd_p)
		return;

	/* Work out how many descriptors have been transmitted */
395
	qcp_rd_p = nfp_net_read_tx_cmpl(tx_ring, dp);
396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469

	if (qcp_rd_p == tx_ring->qcp_rd_p)
		return;

	todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);

	while (todo--) {
		const skb_frag_t *frag;
		struct nfp_nfd3_tx_buf *tx_buf;
		struct sk_buff *skb;
		int fidx, nr_frags;
		int idx;

		idx = D_IDX(tx_ring, tx_ring->rd_p++);
		tx_buf = &tx_ring->txbufs[idx];

		skb = tx_buf->skb;
		if (!skb)
			continue;

		nr_frags = skb_shinfo(skb)->nr_frags;
		fidx = tx_buf->fidx;

		if (fidx == -1) {
			/* unmap head */
			dma_unmap_single(dp->dev, tx_buf->dma_addr,
					 skb_headlen(skb), DMA_TO_DEVICE);

			done_pkts += tx_buf->pkt_cnt;
			done_bytes += tx_buf->real_len;
		} else {
			/* unmap fragment */
			frag = &skb_shinfo(skb)->frags[fidx];
			dma_unmap_page(dp->dev, tx_buf->dma_addr,
				       skb_frag_size(frag), DMA_TO_DEVICE);
		}

		/* check for last gather fragment */
		if (fidx == nr_frags - 1)
			napi_consume_skb(skb, budget);

		tx_buf->dma_addr = 0;
		tx_buf->skb = NULL;
		tx_buf->fidx = -2;
	}

	tx_ring->qcp_rd_p = qcp_rd_p;

	u64_stats_update_begin(&r_vec->tx_sync);
	r_vec->tx_bytes += done_bytes;
	r_vec->tx_pkts += done_pkts;
	u64_stats_update_end(&r_vec->tx_sync);

	if (!dp->netdev)
		return;

	nd_q = netdev_get_tx_queue(dp->netdev, tx_ring->idx);
	netdev_tx_completed_queue(nd_q, done_pkts, done_bytes);
	if (nfp_nfd3_tx_ring_should_wake(tx_ring)) {
		/* Make sure TX thread will see updated tx_ring->rd_p */
		smp_mb();

		if (unlikely(netif_tx_queue_stopped(nd_q)))
			netif_tx_wake_queue(nd_q);
	}

	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
		  "TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);
}

static bool nfp_nfd3_xdp_complete(struct nfp_net_tx_ring *tx_ring)
{
	struct nfp_net_r_vector *r_vec = tx_ring->r_vec;
470
	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
471 472 473 474 475 476
	u32 done_pkts = 0, done_bytes = 0;
	bool done_all;
	int idx, todo;
	u32 qcp_rd_p;

	/* Work out how many descriptors have been transmitted */
477
	qcp_rd_p = nfp_net_read_tx_cmpl(tx_ring, dp);
478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134

	if (qcp_rd_p == tx_ring->qcp_rd_p)
		return true;

	todo = D_IDX(tx_ring, qcp_rd_p - tx_ring->qcp_rd_p);

	done_all = todo <= NFP_NET_XDP_MAX_COMPLETE;
	todo = min(todo, NFP_NET_XDP_MAX_COMPLETE);

	tx_ring->qcp_rd_p = D_IDX(tx_ring, tx_ring->qcp_rd_p + todo);

	done_pkts = todo;
	while (todo--) {
		idx = D_IDX(tx_ring, tx_ring->rd_p);
		tx_ring->rd_p++;

		done_bytes += tx_ring->txbufs[idx].real_len;
	}

	u64_stats_update_begin(&r_vec->tx_sync);
	r_vec->tx_bytes += done_bytes;
	r_vec->tx_pkts += done_pkts;
	u64_stats_update_end(&r_vec->tx_sync);

	WARN_ONCE(tx_ring->wr_p - tx_ring->rd_p > tx_ring->cnt,
		  "XDP TX ring corruption rd_p=%u wr_p=%u cnt=%u\n",
		  tx_ring->rd_p, tx_ring->wr_p, tx_ring->cnt);

	return done_all;
}

/* Receive processing
 */

static void *
nfp_nfd3_napi_alloc_one(struct nfp_net_dp *dp, dma_addr_t *dma_addr)
{
	void *frag;

	if (!dp->xdp_prog) {
		frag = napi_alloc_frag(dp->fl_bufsz);
		if (unlikely(!frag))
			return NULL;
	} else {
		struct page *page;

		page = dev_alloc_page();
		if (unlikely(!page))
			return NULL;
		frag = page_address(page);
	}

	*dma_addr = nfp_net_dma_map_rx(dp, frag);
	if (dma_mapping_error(dp->dev, *dma_addr)) {
		nfp_net_free_frag(frag, dp->xdp_prog);
		nn_dp_warn(dp, "Failed to map DMA RX buffer\n");
		return NULL;
	}

	return frag;
}

/**
 * nfp_nfd3_rx_give_one() - Put mapped skb on the software and hardware rings
 * @dp:		NFP Net data path struct
 * @rx_ring:	RX ring structure
 * @frag:	page fragment buffer
 * @dma_addr:	DMA address of skb mapping
 */
static void
nfp_nfd3_rx_give_one(const struct nfp_net_dp *dp,
		     struct nfp_net_rx_ring *rx_ring,
		     void *frag, dma_addr_t dma_addr)
{
	unsigned int wr_idx;

	wr_idx = D_IDX(rx_ring, rx_ring->wr_p);

	nfp_net_dma_sync_dev_rx(dp, dma_addr);

	/* Stash SKB and DMA address away */
	rx_ring->rxbufs[wr_idx].frag = frag;
	rx_ring->rxbufs[wr_idx].dma_addr = dma_addr;

	/* Fill freelist descriptor */
	rx_ring->rxds[wr_idx].fld.reserved = 0;
	rx_ring->rxds[wr_idx].fld.meta_len_dd = 0;
	nfp_desc_set_dma_addr(&rx_ring->rxds[wr_idx].fld,
			      dma_addr + dp->rx_dma_off);

	rx_ring->wr_p++;
	if (!(rx_ring->wr_p % NFP_NET_FL_BATCH)) {
		/* Update write pointer of the freelist queue. Make
		 * sure all writes are flushed before telling the hardware.
		 */
		wmb();
		nfp_qcp_wr_ptr_add(rx_ring->qcp_fl, NFP_NET_FL_BATCH);
	}
}

/**
 * nfp_nfd3_rx_ring_fill_freelist() - Give buffers from the ring to FW
 * @dp:	     NFP Net data path struct
 * @rx_ring: RX ring to fill
 */
void nfp_nfd3_rx_ring_fill_freelist(struct nfp_net_dp *dp,
				    struct nfp_net_rx_ring *rx_ring)
{
	unsigned int i;

	if (nfp_net_has_xsk_pool_slow(dp, rx_ring->idx))
		return nfp_net_xsk_rx_ring_fill_freelist(rx_ring);

	for (i = 0; i < rx_ring->cnt - 1; i++)
		nfp_nfd3_rx_give_one(dp, rx_ring, rx_ring->rxbufs[i].frag,
				     rx_ring->rxbufs[i].dma_addr);
}

/**
 * nfp_nfd3_rx_csum_has_errors() - group check if rxd has any csum errors
 * @flags: RX descriptor flags field in CPU byte order
 */
static int nfp_nfd3_rx_csum_has_errors(u16 flags)
{
	u16 csum_all_checked, csum_all_ok;

	csum_all_checked = flags & __PCIE_DESC_RX_CSUM_ALL;
	csum_all_ok = flags & __PCIE_DESC_RX_CSUM_ALL_OK;

	return csum_all_checked != (csum_all_ok << PCIE_DESC_RX_CSUM_OK_SHIFT);
}

/**
 * nfp_nfd3_rx_csum() - set SKB checksum field based on RX descriptor flags
 * @dp:  NFP Net data path struct
 * @r_vec: per-ring structure
 * @rxd: Pointer to RX descriptor
 * @meta: Parsed metadata prepend
 * @skb: Pointer to SKB
 */
void
nfp_nfd3_rx_csum(const struct nfp_net_dp *dp, struct nfp_net_r_vector *r_vec,
		 const struct nfp_net_rx_desc *rxd,
		 const struct nfp_meta_parsed *meta, struct sk_buff *skb)
{
	skb_checksum_none_assert(skb);

	if (!(dp->netdev->features & NETIF_F_RXCSUM))
		return;

	if (meta->csum_type) {
		skb->ip_summed = meta->csum_type;
		skb->csum = meta->csum;
		u64_stats_update_begin(&r_vec->rx_sync);
		r_vec->hw_csum_rx_complete++;
		u64_stats_update_end(&r_vec->rx_sync);
		return;
	}

	if (nfp_nfd3_rx_csum_has_errors(le16_to_cpu(rxd->rxd.flags))) {
		u64_stats_update_begin(&r_vec->rx_sync);
		r_vec->hw_csum_rx_error++;
		u64_stats_update_end(&r_vec->rx_sync);
		return;
	}

	/* Assume that the firmware will never report inner CSUM_OK unless outer
	 * L4 headers were successfully parsed. FW will always report zero UDP
	 * checksum as CSUM_OK.
	 */
	if (rxd->rxd.flags & PCIE_DESC_RX_TCP_CSUM_OK ||
	    rxd->rxd.flags & PCIE_DESC_RX_UDP_CSUM_OK) {
		__skb_incr_checksum_unnecessary(skb);
		u64_stats_update_begin(&r_vec->rx_sync);
		r_vec->hw_csum_rx_ok++;
		u64_stats_update_end(&r_vec->rx_sync);
	}

	if (rxd->rxd.flags & PCIE_DESC_RX_I_TCP_CSUM_OK ||
	    rxd->rxd.flags & PCIE_DESC_RX_I_UDP_CSUM_OK) {
		__skb_incr_checksum_unnecessary(skb);
		u64_stats_update_begin(&r_vec->rx_sync);
		r_vec->hw_csum_rx_inner_ok++;
		u64_stats_update_end(&r_vec->rx_sync);
	}
}

static void
nfp_nfd3_set_hash(struct net_device *netdev, struct nfp_meta_parsed *meta,
		  unsigned int type, __be32 *hash)
{
	if (!(netdev->features & NETIF_F_RXHASH))
		return;

	switch (type) {
	case NFP_NET_RSS_IPV4:
	case NFP_NET_RSS_IPV6:
	case NFP_NET_RSS_IPV6_EX:
		meta->hash_type = PKT_HASH_TYPE_L3;
		break;
	default:
		meta->hash_type = PKT_HASH_TYPE_L4;
		break;
	}

	meta->hash = get_unaligned_be32(hash);
}

static void
nfp_nfd3_set_hash_desc(struct net_device *netdev, struct nfp_meta_parsed *meta,
		       void *data, struct nfp_net_rx_desc *rxd)
{
	struct nfp_net_rx_hash *rx_hash = data;

	if (!(rxd->rxd.flags & PCIE_DESC_RX_RSS))
		return;

	nfp_nfd3_set_hash(netdev, meta, get_unaligned_be32(&rx_hash->hash_type),
			  &rx_hash->hash);
}

bool
nfp_nfd3_parse_meta(struct net_device *netdev, struct nfp_meta_parsed *meta,
		    void *data, void *pkt, unsigned int pkt_len, int meta_len)
{
	u32 meta_info;

	meta_info = get_unaligned_be32(data);
	data += 4;

	while (meta_info) {
		switch (meta_info & NFP_NET_META_FIELD_MASK) {
		case NFP_NET_META_HASH:
			meta_info >>= NFP_NET_META_FIELD_SIZE;
			nfp_nfd3_set_hash(netdev, meta,
					  meta_info & NFP_NET_META_FIELD_MASK,
					  (__be32 *)data);
			data += 4;
			break;
		case NFP_NET_META_MARK:
			meta->mark = get_unaligned_be32(data);
			data += 4;
			break;
		case NFP_NET_META_PORTID:
			meta->portid = get_unaligned_be32(data);
			data += 4;
			break;
		case NFP_NET_META_CSUM:
			meta->csum_type = CHECKSUM_COMPLETE;
			meta->csum =
				(__force __wsum)__get_unaligned_cpu32(data);
			data += 4;
			break;
		case NFP_NET_META_RESYNC_INFO:
			if (nfp_net_tls_rx_resync_req(netdev, data, pkt,
						      pkt_len))
				return false;
			data += sizeof(struct nfp_net_tls_resync_req);
			break;
		default:
			return true;
		}

		meta_info >>= NFP_NET_META_FIELD_SIZE;
	}

	return data != pkt;
}

static void
nfp_nfd3_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)
{
	u64_stats_update_begin(&r_vec->rx_sync);
	r_vec->rx_drops++;
	/* If we have both skb and rxbuf the replacement buffer allocation
	 * must have failed, count this as an alloc failure.
	 */
	if (skb && rxbuf)
		r_vec->rx_replace_buf_alloc_fail++;
	u64_stats_update_end(&r_vec->rx_sync);

	/* skb is build based on the frag, free_skb() would free the frag
	 * so to be able to reuse it we need an extra ref.
	 */
	if (skb && rxbuf && skb->head == rxbuf->frag)
		page_ref_inc(virt_to_head_page(rxbuf->frag));
	if (rxbuf)
		nfp_nfd3_rx_give_one(dp, rx_ring, rxbuf->frag, rxbuf->dma_addr);
	if (skb)
		dev_kfree_skb_any(skb);
}

static bool
nfp_nfd3_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)
{
	unsigned int dma_map_sz = dp->fl_bufsz - NFP_NET_RX_BUF_NON_DATA;
	struct nfp_nfd3_tx_buf *txbuf;
	struct nfp_nfd3_tx_desc *txd;
	int wr_idx;

	/* Reject if xdp_adjust_tail grow packet beyond DMA area */
	if (pkt_len + dma_off > dma_map_sz)
		return false;

	if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
		if (!*completed) {
			nfp_nfd3_xdp_complete(tx_ring);
			*completed = true;
		}

		if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
			nfp_nfd3_rx_drop(dp, rx_ring->r_vec, rx_ring, rxbuf,
					 NULL);
			return false;
		}
	}

	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);

	/* Stash the soft descriptor of the head then initialize it */
	txbuf = &tx_ring->txbufs[wr_idx];

	nfp_nfd3_rx_give_one(dp, rx_ring, txbuf->frag, txbuf->dma_addr);

	txbuf->frag = rxbuf->frag;
	txbuf->dma_addr = rxbuf->dma_addr;
	txbuf->fidx = -1;
	txbuf->pkt_cnt = 1;
	txbuf->real_len = pkt_len;

	dma_sync_single_for_device(dp->dev, rxbuf->dma_addr + dma_off,
				   pkt_len, DMA_BIDIRECTIONAL);

	/* Build TX descriptor */
	txd = &tx_ring->txds[wr_idx];
	txd->offset_eop = NFD3_DESC_TX_EOP;
	txd->dma_len = cpu_to_le16(pkt_len);
	nfp_desc_set_dma_addr(txd, rxbuf->dma_addr + dma_off);
	txd->data_len = cpu_to_le16(pkt_len);

	txd->flags = 0;
	txd->mss = 0;
	txd->lso_hdrlen = 0;

	tx_ring->wr_p++;
	tx_ring->wr_ptr_add++;
	return true;
}

/**
 * nfp_nfd3_rx() - receive up to @budget packets on @rx_ring
 * @rx_ring:   RX ring to receive from
 * @budget:    NAPI budget
 *
 * Note, this function is separated out from the napi poll function to
 * more cleanly separate packet receive code from other bookkeeping
 * functions performed in the napi poll function.
 *
 * Return: Number of packets received.
 */
static int nfp_nfd3_rx(struct nfp_net_rx_ring *rx_ring, int budget)
{
	struct nfp_net_r_vector *r_vec = rx_ring->r_vec;
	struct nfp_net_dp *dp = &r_vec->nfp_net->dp;
	struct nfp_net_tx_ring *tx_ring;
	struct bpf_prog *xdp_prog;
	bool xdp_tx_cmpl = false;
	unsigned int true_bufsz;
	struct sk_buff *skb;
	int pkts_polled = 0;
	struct xdp_buff xdp;
	int idx;

	xdp_prog = READ_ONCE(dp->xdp_prog);
	true_bufsz = xdp_prog ? PAGE_SIZE : dp->fl_bufsz;
	xdp_init_buff(&xdp, PAGE_SIZE - NFP_NET_RX_BUF_HEADROOM,
		      &rx_ring->xdp_rxq);
	tx_ring = r_vec->xdp_ring;

	while (pkts_polled < budget) {
		unsigned int meta_len, data_len, meta_off, pkt_len, pkt_off;
		struct nfp_net_rx_buf *rxbuf;
		struct nfp_net_rx_desc *rxd;
		struct nfp_meta_parsed meta;
		bool redir_egress = false;
		struct net_device *netdev;
		dma_addr_t new_dma_addr;
		u32 meta_len_xdp = 0;
		void *new_frag;

		idx = D_IDX(rx_ring, rx_ring->rd_p);

		rxd = &rx_ring->rxds[idx];
		if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
			break;

		/* Memory barrier to ensure that we won't do other reads
		 * before the DD bit.
		 */
		dma_rmb();

		memset(&meta, 0, sizeof(meta));

		rx_ring->rd_p++;
		pkts_polled++;

		rxbuf =	&rx_ring->rxbufs[idx];
		/*         < meta_len >
		 *  <-- [rx_offset] -->
		 *  ---------------------------------------------------------
		 * | [XX] |  metadata  |             packet           | XXXX |
		 *  ---------------------------------------------------------
		 *         <---------------- data_len --------------->
		 *
		 * The rx_offset is fixed for all packets, the meta_len can vary
		 * on a packet by packet basis. If rx_offset is set to zero
		 * (_RX_OFFSET_DYNAMIC) metadata starts at the beginning of the
		 * buffer and is immediately followed by the packet (no [XX]).
		 */
		meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
		data_len = le16_to_cpu(rxd->rxd.data_len);
		pkt_len = data_len - meta_len;

		pkt_off = NFP_NET_RX_BUF_HEADROOM + dp->rx_dma_off;
		if (dp->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
			pkt_off += meta_len;
		else
			pkt_off += dp->rx_offset;
		meta_off = pkt_off - meta_len;

		/* Stats update */
		u64_stats_update_begin(&r_vec->rx_sync);
		r_vec->rx_pkts++;
		r_vec->rx_bytes += pkt_len;
		u64_stats_update_end(&r_vec->rx_sync);

		if (unlikely(meta_len > NFP_NET_MAX_PREPEND ||
			     (dp->rx_offset && meta_len > dp->rx_offset))) {
			nn_dp_warn(dp, "oversized RX packet metadata %u\n",
				   meta_len);
			nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
			continue;
		}

		nfp_net_dma_sync_cpu_rx(dp, rxbuf->dma_addr + meta_off,
					data_len);

		if (!dp->chained_metadata_format) {
			nfp_nfd3_set_hash_desc(dp->netdev, &meta,
					       rxbuf->frag + meta_off, rxd);
		} else if (meta_len) {
			if (unlikely(nfp_nfd3_parse_meta(dp->netdev, &meta,
							 rxbuf->frag + meta_off,
							 rxbuf->frag + pkt_off,
							 pkt_len, meta_len))) {
				nn_dp_warn(dp, "invalid RX packet metadata\n");
				nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf,
						 NULL);
				continue;
			}
		}

		if (xdp_prog && !meta.portid) {
			void *orig_data = rxbuf->frag + pkt_off;
			unsigned int dma_off;
			int act;

			xdp_prepare_buff(&xdp,
					 rxbuf->frag + NFP_NET_RX_BUF_HEADROOM,
					 pkt_off - NFP_NET_RX_BUF_HEADROOM,
					 pkt_len, true);

			act = bpf_prog_run_xdp(xdp_prog, &xdp);

			pkt_len = xdp.data_end - xdp.data;
			pkt_off += xdp.data - orig_data;

			switch (act) {
			case XDP_PASS:
				meta_len_xdp = xdp.data - xdp.data_meta;
				break;
			case XDP_TX:
				dma_off = pkt_off - NFP_NET_RX_BUF_HEADROOM;
				if (unlikely(!nfp_nfd3_tx_xdp_buf(dp, rx_ring,
								  tx_ring,
								  rxbuf,
								  dma_off,
								  pkt_len,
								  &xdp_tx_cmpl)))
					trace_xdp_exception(dp->netdev,
							    xdp_prog, act);
				continue;
			default:
				bpf_warn_invalid_xdp_action(dp->netdev, xdp_prog, act);
				fallthrough;
			case XDP_ABORTED:
				trace_xdp_exception(dp->netdev, xdp_prog, act);
				fallthrough;
			case XDP_DROP:
				nfp_nfd3_rx_give_one(dp, rx_ring, rxbuf->frag,
						     rxbuf->dma_addr);
				continue;
			}
		}

		if (likely(!meta.portid)) {
			netdev = dp->netdev;
		} else if (meta.portid == NFP_META_PORT_ID_CTRL) {
			struct nfp_net *nn = netdev_priv(dp->netdev);

			nfp_app_ctrl_rx_raw(nn->app, rxbuf->frag + pkt_off,
					    pkt_len);
			nfp_nfd3_rx_give_one(dp, rx_ring, rxbuf->frag,
					     rxbuf->dma_addr);
			continue;
		} else {
			struct nfp_net *nn;

			nn = netdev_priv(dp->netdev);
			netdev = nfp_app_dev_get(nn->app, meta.portid,
						 &redir_egress);
			if (unlikely(!netdev)) {
				nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf,
						 NULL);
				continue;
			}

			if (nfp_netdev_is_nfp_repr(netdev))
				nfp_repr_inc_rx_stats(netdev, pkt_len);
		}

		skb = build_skb(rxbuf->frag, true_bufsz);
		if (unlikely(!skb)) {
			nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
			continue;
		}
		new_frag = nfp_nfd3_napi_alloc_one(dp, &new_dma_addr);
		if (unlikely(!new_frag)) {
			nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, skb);
			continue;
		}

		nfp_net_dma_unmap_rx(dp, rxbuf->dma_addr);

		nfp_nfd3_rx_give_one(dp, rx_ring, new_frag, new_dma_addr);

		skb_reserve(skb, pkt_off);
		skb_put(skb, pkt_len);

		skb->mark = meta.mark;
		skb_set_hash(skb, meta.hash, meta.hash_type);

		skb_record_rx_queue(skb, rx_ring->idx);
		skb->protocol = eth_type_trans(skb, netdev);

		nfp_nfd3_rx_csum(dp, r_vec, rxd, &meta, skb);

#ifdef CONFIG_TLS_DEVICE
		if (rxd->rxd.flags & PCIE_DESC_RX_DECRYPTED) {
			skb->decrypted = true;
			u64_stats_update_begin(&r_vec->rx_sync);
			r_vec->hw_tls_rx++;
			u64_stats_update_end(&r_vec->rx_sync);
		}
#endif

		if (rxd->rxd.flags & PCIE_DESC_RX_VLAN)
			__vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q),
					       le16_to_cpu(rxd->rxd.vlan));
		if (meta_len_xdp)
			skb_metadata_set(skb, meta_len_xdp);

		if (likely(!redir_egress)) {
			napi_gro_receive(&rx_ring->r_vec->napi, skb);
		} else {
			skb->dev = netdev;
			skb_reset_network_header(skb);
			__skb_push(skb, ETH_HLEN);
			dev_queue_xmit(skb);
		}
	}

	if (xdp_prog) {
		if (tx_ring->wr_ptr_add)
			nfp_net_tx_xmit_more_flush(tx_ring);
		else if (unlikely(tx_ring->wr_p != tx_ring->rd_p) &&
			 !xdp_tx_cmpl)
			if (!nfp_nfd3_xdp_complete(tx_ring))
				pkts_polled = budget;
	}

	return pkts_polled;
}

/**
 * nfp_nfd3_poll() - napi poll function
 * @napi:    NAPI structure
 * @budget:  NAPI budget
 *
 * Return: number of packets polled.
 */
int nfp_nfd3_poll(struct napi_struct *napi, int budget)
{
	struct nfp_net_r_vector *r_vec =
		container_of(napi, struct nfp_net_r_vector, napi);
	unsigned int pkts_polled = 0;

	if (r_vec->tx_ring)
		nfp_nfd3_tx_complete(r_vec->tx_ring, budget);
	if (r_vec->rx_ring)
		pkts_polled = nfp_nfd3_rx(r_vec->rx_ring, budget);

	if (pkts_polled < budget)
		if (napi_complete_done(napi, pkts_polled))
			nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);

	if (r_vec->nfp_net->rx_coalesce_adapt_on && r_vec->rx_ring) {
		struct dim_sample dim_sample = {};
		unsigned int start;
		u64 pkts, bytes;

		do {
			start = u64_stats_fetch_begin(&r_vec->rx_sync);
			pkts = r_vec->rx_pkts;
			bytes = r_vec->rx_bytes;
		} while (u64_stats_fetch_retry(&r_vec->rx_sync, start));

		dim_update_sample(r_vec->event_ctr, pkts, bytes, &dim_sample);
		net_dim(&r_vec->rx_dim, dim_sample);
	}

	if (r_vec->nfp_net->tx_coalesce_adapt_on && r_vec->tx_ring) {
		struct dim_sample dim_sample = {};
		unsigned int start;
		u64 pkts, bytes;

		do {
			start = u64_stats_fetch_begin(&r_vec->tx_sync);
			pkts = r_vec->tx_pkts;
			bytes = r_vec->tx_bytes;
		} while (u64_stats_fetch_retry(&r_vec->tx_sync, start));

		dim_update_sample(r_vec->event_ctr, pkts, bytes, &dim_sample);
		net_dim(&r_vec->tx_dim, dim_sample);
	}

	return pkts_polled;
}

/* Control device data path
 */

1135 1136 1137
bool
nfp_nfd3_ctrl_tx_one(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
		     struct sk_buff *skb, bool old)
1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223
{
	unsigned int real_len = skb->len, meta_len = 0;
	struct nfp_net_tx_ring *tx_ring;
	struct nfp_nfd3_tx_buf *txbuf;
	struct nfp_nfd3_tx_desc *txd;
	struct nfp_net_dp *dp;
	dma_addr_t dma_addr;
	int wr_idx;

	dp = &r_vec->nfp_net->dp;
	tx_ring = r_vec->tx_ring;

	if (WARN_ON_ONCE(skb_shinfo(skb)->nr_frags)) {
		nn_dp_warn(dp, "Driver's CTRL TX does not implement gather\n");
		goto err_free;
	}

	if (unlikely(nfp_net_tx_full(tx_ring, 1))) {
		u64_stats_update_begin(&r_vec->tx_sync);
		r_vec->tx_busy++;
		u64_stats_update_end(&r_vec->tx_sync);
		if (!old)
			__skb_queue_tail(&r_vec->queue, skb);
		else
			__skb_queue_head(&r_vec->queue, skb);
		return true;
	}

	if (nfp_app_ctrl_has_meta(nn->app)) {
		if (unlikely(skb_headroom(skb) < 8)) {
			nn_dp_warn(dp, "CTRL TX on skb without headroom\n");
			goto err_free;
		}
		meta_len = 8;
		put_unaligned_be32(NFP_META_PORT_ID_CTRL, skb_push(skb, 4));
		put_unaligned_be32(NFP_NET_META_PORTID, skb_push(skb, 4));
	}

	/* Start with the head skbuf */
	dma_addr = dma_map_single(dp->dev, skb->data, skb_headlen(skb),
				  DMA_TO_DEVICE);
	if (dma_mapping_error(dp->dev, dma_addr))
		goto err_dma_warn;

	wr_idx = D_IDX(tx_ring, tx_ring->wr_p);

	/* Stash the soft descriptor of the head then initialize it */
	txbuf = &tx_ring->txbufs[wr_idx];
	txbuf->skb = skb;
	txbuf->dma_addr = dma_addr;
	txbuf->fidx = -1;
	txbuf->pkt_cnt = 1;
	txbuf->real_len = real_len;

	/* Build TX descriptor */
	txd = &tx_ring->txds[wr_idx];
	txd->offset_eop = meta_len | NFD3_DESC_TX_EOP;
	txd->dma_len = cpu_to_le16(skb_headlen(skb));
	nfp_desc_set_dma_addr(txd, dma_addr);
	txd->data_len = cpu_to_le16(skb->len);

	txd->flags = 0;
	txd->mss = 0;
	txd->lso_hdrlen = 0;

	tx_ring->wr_p++;
	tx_ring->wr_ptr_add++;
	nfp_net_tx_xmit_more_flush(tx_ring);

	return false;

err_dma_warn:
	nn_dp_warn(dp, "Failed to DMA map TX CTRL buffer\n");
err_free:
	u64_stats_update_begin(&r_vec->tx_sync);
	r_vec->tx_errors++;
	u64_stats_update_end(&r_vec->tx_sync);
	dev_kfree_skb_any(skb);
	return false;
}

static void __nfp_ctrl_tx_queued(struct nfp_net_r_vector *r_vec)
{
	struct sk_buff *skb;

	while ((skb = __skb_dequeue(&r_vec->queue)))
1224
		if (nfp_nfd3_ctrl_tx_one(r_vec->nfp_net, r_vec, skb, true))
1225 1226 1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 1277 1278 1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 1316 1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350
			return;
}

static bool
nfp_ctrl_meta_ok(struct nfp_net *nn, void *data, unsigned int meta_len)
{
	u32 meta_type, meta_tag;

	if (!nfp_app_ctrl_has_meta(nn->app))
		return !meta_len;

	if (meta_len != 8)
		return false;

	meta_type = get_unaligned_be32(data);
	meta_tag = get_unaligned_be32(data + 4);

	return (meta_type == NFP_NET_META_PORTID &&
		meta_tag == NFP_META_PORT_ID_CTRL);
}

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)
{
	unsigned int meta_len, data_len, meta_off, pkt_len, pkt_off;
	struct nfp_net_rx_buf *rxbuf;
	struct nfp_net_rx_desc *rxd;
	dma_addr_t new_dma_addr;
	struct sk_buff *skb;
	void *new_frag;
	int idx;

	idx = D_IDX(rx_ring, rx_ring->rd_p);

	rxd = &rx_ring->rxds[idx];
	if (!(rxd->rxd.meta_len_dd & PCIE_DESC_RX_DD))
		return false;

	/* Memory barrier to ensure that we won't do other reads
	 * before the DD bit.
	 */
	dma_rmb();

	rx_ring->rd_p++;

	rxbuf =	&rx_ring->rxbufs[idx];
	meta_len = rxd->rxd.meta_len_dd & PCIE_DESC_RX_META_LEN_MASK;
	data_len = le16_to_cpu(rxd->rxd.data_len);
	pkt_len = data_len - meta_len;

	pkt_off = NFP_NET_RX_BUF_HEADROOM + dp->rx_dma_off;
	if (dp->rx_offset == NFP_NET_CFG_RX_OFFSET_DYNAMIC)
		pkt_off += meta_len;
	else
		pkt_off += dp->rx_offset;
	meta_off = pkt_off - meta_len;

	/* Stats update */
	u64_stats_update_begin(&r_vec->rx_sync);
	r_vec->rx_pkts++;
	r_vec->rx_bytes += pkt_len;
	u64_stats_update_end(&r_vec->rx_sync);

	nfp_net_dma_sync_cpu_rx(dp, rxbuf->dma_addr + meta_off,	data_len);

	if (unlikely(!nfp_ctrl_meta_ok(nn, rxbuf->frag + meta_off, meta_len))) {
		nn_dp_warn(dp, "incorrect metadata for ctrl packet (%d)\n",
			   meta_len);
		nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
		return true;
	}

	skb = build_skb(rxbuf->frag, dp->fl_bufsz);
	if (unlikely(!skb)) {
		nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, NULL);
		return true;
	}
	new_frag = nfp_nfd3_napi_alloc_one(dp, &new_dma_addr);
	if (unlikely(!new_frag)) {
		nfp_nfd3_rx_drop(dp, r_vec, rx_ring, rxbuf, skb);
		return true;
	}

	nfp_net_dma_unmap_rx(dp, rxbuf->dma_addr);

	nfp_nfd3_rx_give_one(dp, rx_ring, new_frag, new_dma_addr);

	skb_reserve(skb, pkt_off);
	skb_put(skb, pkt_len);

	nfp_app_ctrl_rx(nn->app, skb);

	return true;
}

static bool nfp_ctrl_rx(struct nfp_net_r_vector *r_vec)
{
	struct nfp_net_rx_ring *rx_ring = r_vec->rx_ring;
	struct nfp_net *nn = r_vec->nfp_net;
	struct nfp_net_dp *dp = &nn->dp;
	unsigned int budget = 512;

	while (nfp_ctrl_rx_one(nn, dp, r_vec, rx_ring) && budget--)
		continue;

	return budget;
}

void nfp_nfd3_ctrl_poll(struct tasklet_struct *t)
{
	struct nfp_net_r_vector *r_vec = from_tasklet(r_vec, t, tasklet);

	spin_lock(&r_vec->lock);
	nfp_nfd3_tx_complete(r_vec->tx_ring, 0);
	__nfp_ctrl_tx_queued(r_vec);
	spin_unlock(&r_vec->lock);

	if (nfp_ctrl_rx(r_vec)) {
		nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
	} else {
		tasklet_schedule(&r_vec->tasklet);
		nn_dp_warn(&r_vec->nfp_net->dp,
			   "control message budget exceeded!\n");
	}
}