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v5.9
   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (c) 2018, Intel Corporation. */
   3
   4/* The driver transmit and receive code */
   5
   6#include <linux/prefetch.h>
   7#include <linux/mm.h>
 
 
   8#include <linux/bpf_trace.h>
 
 
   9#include <net/xdp.h>
  10#include "ice_txrx_lib.h"
  11#include "ice_lib.h"
  12#include "ice.h"
 
  13#include "ice_dcb_lib.h"
  14#include "ice_xsk.h"
 
  15
  16#define ICE_RX_HDR_SIZE		256
  17
  18#define FDIR_DESC_RXDID 0x40
  19#define ICE_FDIR_CLEAN_DELAY 10
  20
  21/**
  22 * ice_prgm_fdir_fltr - Program a Flow Director filter
  23 * @vsi: VSI to send dummy packet
  24 * @fdir_desc: flow director descriptor
  25 * @raw_packet: allocated buffer for flow director
  26 */
  27int
  28ice_prgm_fdir_fltr(struct ice_vsi *vsi, struct ice_fltr_desc *fdir_desc,
  29		   u8 *raw_packet)
  30{
  31	struct ice_tx_buf *tx_buf, *first;
  32	struct ice_fltr_desc *f_desc;
  33	struct ice_tx_desc *tx_desc;
  34	struct ice_ring *tx_ring;
  35	struct device *dev;
  36	dma_addr_t dma;
  37	u32 td_cmd;
  38	u16 i;
  39
  40	/* VSI and Tx ring */
  41	if (!vsi)
  42		return -ENOENT;
  43	tx_ring = vsi->tx_rings[0];
  44	if (!tx_ring || !tx_ring->desc)
  45		return -ENOENT;
  46	dev = tx_ring->dev;
  47
  48	/* we are using two descriptors to add/del a filter and we can wait */
  49	for (i = ICE_FDIR_CLEAN_DELAY; ICE_DESC_UNUSED(tx_ring) < 2; i--) {
  50		if (!i)
  51			return -EAGAIN;
  52		msleep_interruptible(1);
  53	}
  54
  55	dma = dma_map_single(dev, raw_packet, ICE_FDIR_MAX_RAW_PKT_SIZE,
  56			     DMA_TO_DEVICE);
  57
  58	if (dma_mapping_error(dev, dma))
  59		return -EINVAL;
  60
  61	/* grab the next descriptor */
  62	i = tx_ring->next_to_use;
  63	first = &tx_ring->tx_buf[i];
  64	f_desc = ICE_TX_FDIRDESC(tx_ring, i);
  65	memcpy(f_desc, fdir_desc, sizeof(*f_desc));
  66
  67	i++;
  68	i = (i < tx_ring->count) ? i : 0;
  69	tx_desc = ICE_TX_DESC(tx_ring, i);
  70	tx_buf = &tx_ring->tx_buf[i];
  71
  72	i++;
  73	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
  74
  75	memset(tx_buf, 0, sizeof(*tx_buf));
  76	dma_unmap_len_set(tx_buf, len, ICE_FDIR_MAX_RAW_PKT_SIZE);
  77	dma_unmap_addr_set(tx_buf, dma, dma);
  78
  79	tx_desc->buf_addr = cpu_to_le64(dma);
  80	td_cmd = ICE_TXD_LAST_DESC_CMD | ICE_TX_DESC_CMD_DUMMY |
  81		 ICE_TX_DESC_CMD_RE;
  82
  83	tx_buf->tx_flags = ICE_TX_FLAGS_DUMMY_PKT;
  84	tx_buf->raw_buf = raw_packet;
  85
  86	tx_desc->cmd_type_offset_bsz =
  87		ice_build_ctob(td_cmd, 0, ICE_FDIR_MAX_RAW_PKT_SIZE, 0);
  88
  89	/* Force memory write to complete before letting h/w know
  90	 * there are new descriptors to fetch.
  91	 */
  92	wmb();
  93
  94	/* mark the data descriptor to be watched */
  95	first->next_to_watch = tx_desc;
  96
  97	writel(tx_ring->next_to_use, tx_ring->tail);
  98
  99	return 0;
 100}
 101
 102/**
 103 * ice_unmap_and_free_tx_buf - Release a Tx buffer
 104 * @ring: the ring that owns the buffer
 105 * @tx_buf: the buffer to free
 106 */
 107static void
 108ice_unmap_and_free_tx_buf(struct ice_ring *ring, struct ice_tx_buf *tx_buf)
 109{
 110	if (tx_buf->skb) {
 111		if (tx_buf->tx_flags & ICE_TX_FLAGS_DUMMY_PKT)
 112			devm_kfree(ring->dev, tx_buf->raw_buf);
 113		else if (ice_ring_is_xdp(ring))
 114			page_frag_free(tx_buf->raw_buf);
 115		else
 116			dev_kfree_skb_any(tx_buf->skb);
 117		if (dma_unmap_len(tx_buf, len))
 118			dma_unmap_single(ring->dev,
 119					 dma_unmap_addr(tx_buf, dma),
 120					 dma_unmap_len(tx_buf, len),
 121					 DMA_TO_DEVICE);
 122	} else if (dma_unmap_len(tx_buf, len)) {
 123		dma_unmap_page(ring->dev,
 124			       dma_unmap_addr(tx_buf, dma),
 125			       dma_unmap_len(tx_buf, len),
 126			       DMA_TO_DEVICE);
 127	}
 128
 129	tx_buf->next_to_watch = NULL;
 130	tx_buf->skb = NULL;
 131	dma_unmap_len_set(tx_buf, len, 0);
 132	/* tx_buf must be completely set up in the transmit path */
 133}
 134
 135static struct netdev_queue *txring_txq(const struct ice_ring *ring)
 136{
 137	return netdev_get_tx_queue(ring->netdev, ring->q_index);
 138}
 139
 140/**
 141 * ice_clean_tx_ring - Free any empty Tx buffers
 142 * @tx_ring: ring to be cleaned
 143 */
 144void ice_clean_tx_ring(struct ice_ring *tx_ring)
 145{
 
 146	u16 i;
 147
 148	if (ice_ring_is_xdp(tx_ring) && tx_ring->xsk_umem) {
 149		ice_xsk_clean_xdp_ring(tx_ring);
 150		goto tx_skip_free;
 151	}
 152
 153	/* ring already cleared, nothing to do */
 154	if (!tx_ring->tx_buf)
 155		return;
 156
 157	/* Free all the Tx ring sk_buffs */
 158	for (i = 0; i < tx_ring->count; i++)
 159		ice_unmap_and_free_tx_buf(tx_ring, &tx_ring->tx_buf[i]);
 160
 161tx_skip_free:
 162	memset(tx_ring->tx_buf, 0, sizeof(*tx_ring->tx_buf) * tx_ring->count);
 163
 
 
 164	/* Zero out the descriptor ring */
 165	memset(tx_ring->desc, 0, tx_ring->size);
 166
 167	tx_ring->next_to_use = 0;
 168	tx_ring->next_to_clean = 0;
 
 
 169
 170	if (!tx_ring->netdev)
 171		return;
 172
 173	/* cleanup Tx queue statistics */
 174	netdev_tx_reset_queue(txring_txq(tx_ring));
 175}
 176
 177/**
 178 * ice_free_tx_ring - Free Tx resources per queue
 179 * @tx_ring: Tx descriptor ring for a specific queue
 180 *
 181 * Free all transmit software resources
 182 */
 183void ice_free_tx_ring(struct ice_ring *tx_ring)
 184{
 
 
 185	ice_clean_tx_ring(tx_ring);
 186	devm_kfree(tx_ring->dev, tx_ring->tx_buf);
 187	tx_ring->tx_buf = NULL;
 188
 189	if (tx_ring->desc) {
 190		dmam_free_coherent(tx_ring->dev, tx_ring->size,
 
 
 191				   tx_ring->desc, tx_ring->dma);
 192		tx_ring->desc = NULL;
 193	}
 194}
 195
 196/**
 197 * ice_clean_tx_irq - Reclaim resources after transmit completes
 198 * @tx_ring: Tx ring to clean
 199 * @napi_budget: Used to determine if we are in netpoll
 200 *
 201 * Returns true if there's any budget left (e.g. the clean is finished)
 202 */
 203static bool ice_clean_tx_irq(struct ice_ring *tx_ring, int napi_budget)
 204{
 205	unsigned int total_bytes = 0, total_pkts = 0;
 206	unsigned int budget = ICE_DFLT_IRQ_WORK;
 207	struct ice_vsi *vsi = tx_ring->vsi;
 208	s16 i = tx_ring->next_to_clean;
 209	struct ice_tx_desc *tx_desc;
 210	struct ice_tx_buf *tx_buf;
 211
 
 
 
 212	tx_buf = &tx_ring->tx_buf[i];
 213	tx_desc = ICE_TX_DESC(tx_ring, i);
 214	i -= tx_ring->count;
 215
 216	prefetch(&vsi->state);
 217
 218	do {
 219		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
 220
 221		/* if next_to_watch is not set then there is no work pending */
 222		if (!eop_desc)
 223			break;
 224
 
 
 
 225		smp_rmb();	/* prevent any other reads prior to eop_desc */
 226
 
 227		/* if the descriptor isn't done, no work yet to do */
 228		if (!(eop_desc->cmd_type_offset_bsz &
 229		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
 230			break;
 231
 232		/* clear next_to_watch to prevent false hangs */
 233		tx_buf->next_to_watch = NULL;
 234
 235		/* update the statistics for this packet */
 236		total_bytes += tx_buf->bytecount;
 237		total_pkts += tx_buf->gso_segs;
 238
 239		if (ice_ring_is_xdp(tx_ring))
 240			page_frag_free(tx_buf->raw_buf);
 241		else
 242			/* free the skb */
 243			napi_consume_skb(tx_buf->skb, napi_budget);
 244
 245		/* unmap skb header data */
 246		dma_unmap_single(tx_ring->dev,
 247				 dma_unmap_addr(tx_buf, dma),
 248				 dma_unmap_len(tx_buf, len),
 249				 DMA_TO_DEVICE);
 250
 251		/* clear tx_buf data */
 252		tx_buf->skb = NULL;
 253		dma_unmap_len_set(tx_buf, len, 0);
 254
 255		/* unmap remaining buffers */
 256		while (tx_desc != eop_desc) {
 
 257			tx_buf++;
 258			tx_desc++;
 259			i++;
 260			if (unlikely(!i)) {
 261				i -= tx_ring->count;
 262				tx_buf = tx_ring->tx_buf;
 263				tx_desc = ICE_TX_DESC(tx_ring, 0);
 264			}
 265
 266			/* unmap any remaining paged data */
 267			if (dma_unmap_len(tx_buf, len)) {
 268				dma_unmap_page(tx_ring->dev,
 269					       dma_unmap_addr(tx_buf, dma),
 270					       dma_unmap_len(tx_buf, len),
 271					       DMA_TO_DEVICE);
 272				dma_unmap_len_set(tx_buf, len, 0);
 273			}
 274		}
 
 275
 276		/* move us one more past the eop_desc for start of next pkt */
 277		tx_buf++;
 278		tx_desc++;
 279		i++;
 280		if (unlikely(!i)) {
 281			i -= tx_ring->count;
 282			tx_buf = tx_ring->tx_buf;
 283			tx_desc = ICE_TX_DESC(tx_ring, 0);
 284		}
 285
 286		prefetch(tx_desc);
 287
 288		/* update budget accounting */
 289		budget--;
 290	} while (likely(budget));
 291
 292	i += tx_ring->count;
 293	tx_ring->next_to_clean = i;
 294
 295	ice_update_tx_ring_stats(tx_ring, total_pkts, total_bytes);
 296
 297	if (ice_ring_is_xdp(tx_ring))
 298		return !!budget;
 299
 300	netdev_tx_completed_queue(txring_txq(tx_ring), total_pkts,
 301				  total_bytes);
 302
 303#define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
 304	if (unlikely(total_pkts && netif_carrier_ok(tx_ring->netdev) &&
 305		     (ICE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
 306		/* Make sure that anybody stopping the queue after this
 307		 * sees the new next_to_clean.
 308		 */
 309		smp_mb();
 310		if (__netif_subqueue_stopped(tx_ring->netdev,
 311					     tx_ring->q_index) &&
 312		    !test_bit(__ICE_DOWN, vsi->state)) {
 313			netif_wake_subqueue(tx_ring->netdev,
 314					    tx_ring->q_index);
 315			++tx_ring->tx_stats.restart_q;
 316		}
 317	}
 318
 319	return !!budget;
 320}
 321
 322/**
 323 * ice_setup_tx_ring - Allocate the Tx descriptors
 324 * @tx_ring: the Tx ring to set up
 325 *
 326 * Return 0 on success, negative on error
 327 */
 328int ice_setup_tx_ring(struct ice_ring *tx_ring)
 329{
 330	struct device *dev = tx_ring->dev;
 
 331
 332	if (!dev)
 333		return -ENOMEM;
 334
 335	/* warn if we are about to overwrite the pointer */
 336	WARN_ON(tx_ring->tx_buf);
 337	tx_ring->tx_buf =
 338		devm_kzalloc(dev, sizeof(*tx_ring->tx_buf) * tx_ring->count,
 339			     GFP_KERNEL);
 340	if (!tx_ring->tx_buf)
 341		return -ENOMEM;
 342
 343	/* round up to nearest page */
 344	tx_ring->size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
 345			      PAGE_SIZE);
 346	tx_ring->desc = dmam_alloc_coherent(dev, tx_ring->size, &tx_ring->dma,
 347					    GFP_KERNEL);
 348	if (!tx_ring->desc) {
 349		dev_err(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
 350			tx_ring->size);
 351		goto err;
 352	}
 353
 354	tx_ring->next_to_use = 0;
 355	tx_ring->next_to_clean = 0;
 356	tx_ring->tx_stats.prev_pkt = -1;
 357	return 0;
 358
 359err:
 360	devm_kfree(dev, tx_ring->tx_buf);
 361	tx_ring->tx_buf = NULL;
 362	return -ENOMEM;
 363}
 364
 365/**
 366 * ice_clean_rx_ring - Free Rx buffers
 367 * @rx_ring: ring to be cleaned
 368 */
 369void ice_clean_rx_ring(struct ice_ring *rx_ring)
 370{
 371	struct device *dev = rx_ring->dev;
 
 372	u16 i;
 373
 374	/* ring already cleared, nothing to do */
 375	if (!rx_ring->rx_buf)
 376		return;
 377
 378	if (rx_ring->xsk_umem) {
 
 
 
 
 
 379		ice_xsk_clean_rx_ring(rx_ring);
 380		goto rx_skip_free;
 381	}
 382
 383	/* Free all the Rx ring sk_buffs */
 384	for (i = 0; i < rx_ring->count; i++) {
 385		struct ice_rx_buf *rx_buf = &rx_ring->rx_buf[i];
 386
 387		if (rx_buf->skb) {
 388			dev_kfree_skb(rx_buf->skb);
 389			rx_buf->skb = NULL;
 390		}
 391		if (!rx_buf->page)
 392			continue;
 393
 394		/* Invalidate cache lines that may have been written to by
 395		 * device so that we avoid corrupting memory.
 396		 */
 397		dma_sync_single_range_for_cpu(dev, rx_buf->dma,
 398					      rx_buf->page_offset,
 399					      rx_ring->rx_buf_len,
 400					      DMA_FROM_DEVICE);
 401
 402		/* free resources associated with mapping */
 403		dma_unmap_page_attrs(dev, rx_buf->dma, ice_rx_pg_size(rx_ring),
 404				     DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
 405		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
 406
 407		rx_buf->page = NULL;
 408		rx_buf->page_offset = 0;
 409	}
 410
 411rx_skip_free:
 412	memset(rx_ring->rx_buf, 0, sizeof(*rx_ring->rx_buf) * rx_ring->count);
 
 
 
 413
 414	/* Zero out the descriptor ring */
 415	memset(rx_ring->desc, 0, rx_ring->size);
 
 
 416
 417	rx_ring->next_to_alloc = 0;
 418	rx_ring->next_to_clean = 0;
 419	rx_ring->next_to_use = 0;
 420}
 421
 422/**
 423 * ice_free_rx_ring - Free Rx resources
 424 * @rx_ring: ring to clean the resources from
 425 *
 426 * Free all receive software resources
 427 */
 428void ice_free_rx_ring(struct ice_ring *rx_ring)
 429{
 
 
 430	ice_clean_rx_ring(rx_ring);
 431	if (rx_ring->vsi->type == ICE_VSI_PF)
 432		if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
 433			xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 434	rx_ring->xdp_prog = NULL;
 435	devm_kfree(rx_ring->dev, rx_ring->rx_buf);
 436	rx_ring->rx_buf = NULL;
 
 
 
 
 
 437
 438	if (rx_ring->desc) {
 439		dmam_free_coherent(rx_ring->dev, rx_ring->size,
 
 
 440				   rx_ring->desc, rx_ring->dma);
 441		rx_ring->desc = NULL;
 442	}
 443}
 444
 445/**
 446 * ice_setup_rx_ring - Allocate the Rx descriptors
 447 * @rx_ring: the Rx ring to set up
 448 *
 449 * Return 0 on success, negative on error
 450 */
 451int ice_setup_rx_ring(struct ice_ring *rx_ring)
 452{
 453	struct device *dev = rx_ring->dev;
 
 454
 455	if (!dev)
 456		return -ENOMEM;
 457
 458	/* warn if we are about to overwrite the pointer */
 459	WARN_ON(rx_ring->rx_buf);
 460	rx_ring->rx_buf =
 461		devm_kzalloc(dev, sizeof(*rx_ring->rx_buf) * rx_ring->count,
 462			     GFP_KERNEL);
 463	if (!rx_ring->rx_buf)
 464		return -ENOMEM;
 465
 466	/* round up to nearest page */
 467	rx_ring->size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
 468			      PAGE_SIZE);
 469	rx_ring->desc = dmam_alloc_coherent(dev, rx_ring->size, &rx_ring->dma,
 470					    GFP_KERNEL);
 471	if (!rx_ring->desc) {
 472		dev_err(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
 473			rx_ring->size);
 474		goto err;
 475	}
 476
 477	rx_ring->next_to_use = 0;
 478	rx_ring->next_to_clean = 0;
 479
 480	if (ice_is_xdp_ena_vsi(rx_ring->vsi))
 481		WRITE_ONCE(rx_ring->xdp_prog, rx_ring->vsi->xdp_prog);
 482
 483	if (rx_ring->vsi->type == ICE_VSI_PF &&
 484	    !xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
 485		if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
 486				     rx_ring->q_index))
 487			goto err;
 488	return 0;
 489
 490err:
 491	devm_kfree(dev, rx_ring->rx_buf);
 492	rx_ring->rx_buf = NULL;
 493	return -ENOMEM;
 494}
 495
 496/**
 497 * ice_rx_offset - Return expected offset into page to access data
 498 * @rx_ring: Ring we are requesting offset of
 499 *
 500 * Returns the offset value for ring into the data buffer.
 501 */
 502static unsigned int ice_rx_offset(struct ice_ring *rx_ring)
 503{
 504	if (ice_ring_uses_build_skb(rx_ring))
 505		return ICE_SKB_PAD;
 506	else if (ice_is_xdp_ena_vsi(rx_ring->vsi))
 507		return XDP_PACKET_HEADROOM;
 508
 509	return 0;
 510}
 511
 512static unsigned int
 513ice_rx_frame_truesize(struct ice_ring *rx_ring, unsigned int __maybe_unused size)
 514{
 515	unsigned int truesize;
 516
 517#if (PAGE_SIZE < 8192)
 518	truesize = ice_rx_pg_size(rx_ring) / 2; /* Must be power-of-2 */
 519#else
 520	truesize = ice_rx_offset(rx_ring) ?
 521		SKB_DATA_ALIGN(ice_rx_offset(rx_ring) + size) +
 522		SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) :
 523		SKB_DATA_ALIGN(size);
 524#endif
 525	return truesize;
 526}
 527
 528/**
 529 * ice_run_xdp - Executes an XDP program on initialized xdp_buff
 530 * @rx_ring: Rx ring
 531 * @xdp: xdp_buff used as input to the XDP program
 532 * @xdp_prog: XDP program to run
 
 533 *
 534 * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR}
 535 */
 536static int
 537ice_run_xdp(struct ice_ring *rx_ring, struct xdp_buff *xdp,
 538	    struct bpf_prog *xdp_prog)
 539{
 540	int err, result = ICE_XDP_PASS;
 541	struct ice_ring *xdp_ring;
 542	u32 act;
 543
 544	act = bpf_prog_run_xdp(xdp_prog, xdp);
 545	switch (act) {
 546	case XDP_PASS:
 547		break;
 548	case XDP_TX:
 549		xdp_ring = rx_ring->vsi->xdp_rings[smp_processor_id()];
 550		result = ice_xmit_xdp_buff(xdp, xdp_ring);
 551		break;
 
 
 
 
 
 552	case XDP_REDIRECT:
 553		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
 554		result = !err ? ICE_XDP_REDIR : ICE_XDP_CONSUMED;
 555		break;
 
 556	default:
 557		bpf_warn_invalid_xdp_action(act);
 558		fallthrough;
 559	case XDP_ABORTED:
 
 560		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
 561		fallthrough;
 562	case XDP_DROP:
 563		result = ICE_XDP_CONSUMED;
 564		break;
 565	}
 566
 567	return result;
 568}
 569
 570/**
 571 * ice_xdp_xmit - submit packets to XDP ring for transmission
 572 * @dev: netdev
 573 * @n: number of XDP frames to be transmitted
 574 * @frames: XDP frames to be transmitted
 575 * @flags: transmit flags
 576 *
 577 * Returns number of frames successfully sent. Frames that fail are
 578 * free'ed via XDP return API.
 579 * For error cases, a negative errno code is returned and no-frames
 580 * are transmitted (caller must handle freeing frames).
 581 */
 582int
 583ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 584	     u32 flags)
 585{
 586	struct ice_netdev_priv *np = netdev_priv(dev);
 587	unsigned int queue_index = smp_processor_id();
 588	struct ice_vsi *vsi = np->vsi;
 589	struct ice_ring *xdp_ring;
 590	int drops = 0, i;
 591
 592	if (test_bit(__ICE_DOWN, vsi->state))
 593		return -ENETDOWN;
 594
 595	if (!ice_is_xdp_ena_vsi(vsi) || queue_index >= vsi->num_xdp_txq)
 596		return -ENXIO;
 597
 598	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
 599		return -EINVAL;
 600
 601	xdp_ring = vsi->xdp_rings[queue_index];
 
 
 
 
 
 
 
 
 
 
 602	for (i = 0; i < n; i++) {
 603		struct xdp_frame *xdpf = frames[i];
 604		int err;
 605
 606		err = ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
 607		if (err != ICE_XDP_TX) {
 608			xdp_return_frame_rx_napi(xdpf);
 609			drops++;
 610		}
 611	}
 612
 613	if (unlikely(flags & XDP_XMIT_FLUSH))
 614		ice_xdp_ring_update_tail(xdp_ring);
 615
 616	return n - drops;
 
 
 
 617}
 618
 619/**
 620 * ice_alloc_mapped_page - recycle or make a new page
 621 * @rx_ring: ring to use
 622 * @bi: rx_buf struct to modify
 623 *
 624 * Returns true if the page was successfully allocated or
 625 * reused.
 626 */
 627static bool
 628ice_alloc_mapped_page(struct ice_ring *rx_ring, struct ice_rx_buf *bi)
 629{
 630	struct page *page = bi->page;
 631	dma_addr_t dma;
 632
 633	/* since we are recycling buffers we should seldom need to alloc */
 634	if (likely(page))
 635		return true;
 636
 637	/* alloc new page for storage */
 638	page = dev_alloc_pages(ice_rx_pg_order(rx_ring));
 639	if (unlikely(!page)) {
 640		rx_ring->rx_stats.alloc_page_failed++;
 641		return false;
 642	}
 643
 644	/* map page for use */
 645	dma = dma_map_page_attrs(rx_ring->dev, page, 0, ice_rx_pg_size(rx_ring),
 646				 DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
 647
 648	/* if mapping failed free memory back to system since
 649	 * there isn't much point in holding memory we can't use
 650	 */
 651	if (dma_mapping_error(rx_ring->dev, dma)) {
 652		__free_pages(page, ice_rx_pg_order(rx_ring));
 653		rx_ring->rx_stats.alloc_page_failed++;
 654		return false;
 655	}
 656
 657	bi->dma = dma;
 658	bi->page = page;
 659	bi->page_offset = ice_rx_offset(rx_ring);
 660	page_ref_add(page, USHRT_MAX - 1);
 661	bi->pagecnt_bias = USHRT_MAX;
 662
 663	return true;
 664}
 665
 666/**
 667 * ice_alloc_rx_bufs - Replace used receive buffers
 668 * @rx_ring: ring to place buffers on
 669 * @cleaned_count: number of buffers to replace
 670 *
 671 * Returns false if all allocations were successful, true if any fail. Returning
 672 * true signals to the caller that we didn't replace cleaned_count buffers and
 673 * there is more work to do.
 674 *
 675 * First, try to clean "cleaned_count" Rx buffers. Then refill the cleaned Rx
 676 * buffers. Then bump tail at most one time. Grouping like this lets us avoid
 677 * multiple tail writes per call.
 678 */
 679bool ice_alloc_rx_bufs(struct ice_ring *rx_ring, u16 cleaned_count)
 680{
 681	union ice_32b_rx_flex_desc *rx_desc;
 682	u16 ntu = rx_ring->next_to_use;
 683	struct ice_rx_buf *bi;
 684
 685	/* do nothing if no valid netdev defined */
 686	if ((!rx_ring->netdev && rx_ring->vsi->type != ICE_VSI_CTRL) ||
 687	    !cleaned_count)
 688		return false;
 689
 690	/* get the Rx descriptor and buffer based on next_to_use */
 691	rx_desc = ICE_RX_DESC(rx_ring, ntu);
 692	bi = &rx_ring->rx_buf[ntu];
 693
 694	do {
 695		/* if we fail here, we have work remaining */
 696		if (!ice_alloc_mapped_page(rx_ring, bi))
 697			break;
 698
 699		/* sync the buffer for use by the device */
 700		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
 701						 bi->page_offset,
 702						 rx_ring->rx_buf_len,
 703						 DMA_FROM_DEVICE);
 704
 705		/* Refresh the desc even if buffer_addrs didn't change
 706		 * because each write-back erases this info.
 707		 */
 708		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
 709
 710		rx_desc++;
 711		bi++;
 712		ntu++;
 713		if (unlikely(ntu == rx_ring->count)) {
 714			rx_desc = ICE_RX_DESC(rx_ring, 0);
 715			bi = rx_ring->rx_buf;
 716			ntu = 0;
 717		}
 718
 719		/* clear the status bits for the next_to_use descriptor */
 720		rx_desc->wb.status_error0 = 0;
 721
 722		cleaned_count--;
 723	} while (cleaned_count);
 724
 725	if (rx_ring->next_to_use != ntu)
 726		ice_release_rx_desc(rx_ring, ntu);
 727
 728	return !!cleaned_count;
 729}
 730
 731/**
 732 * ice_page_is_reserved - check if reuse is possible
 733 * @page: page struct to check
 734 */
 735static bool ice_page_is_reserved(struct page *page)
 736{
 737	return (page_to_nid(page) != numa_mem_id()) || page_is_pfmemalloc(page);
 738}
 739
 740/**
 741 * ice_rx_buf_adjust_pg_offset - Prepare Rx buffer for reuse
 742 * @rx_buf: Rx buffer to adjust
 743 * @size: Size of adjustment
 744 *
 745 * Update the offset within page so that Rx buf will be ready to be reused.
 746 * For systems with PAGE_SIZE < 8192 this function will flip the page offset
 747 * so the second half of page assigned to Rx buffer will be used, otherwise
 748 * the offset is moved by "size" bytes
 749 */
 750static void
 751ice_rx_buf_adjust_pg_offset(struct ice_rx_buf *rx_buf, unsigned int size)
 752{
 753#if (PAGE_SIZE < 8192)
 754	/* flip page offset to other buffer */
 755	rx_buf->page_offset ^= size;
 756#else
 757	/* move offset up to the next cache line */
 758	rx_buf->page_offset += size;
 759#endif
 760}
 761
 762/**
 763 * ice_can_reuse_rx_page - Determine if page can be reused for another Rx
 764 * @rx_buf: buffer containing the page
 
 765 *
 766 * If page is reusable, we have a green light for calling ice_reuse_rx_page,
 767 * which will assign the current buffer to the buffer that next_to_alloc is
 768 * pointing to; otherwise, the DMA mapping needs to be destroyed and
 769 * page freed
 770 */
 771static bool ice_can_reuse_rx_page(struct ice_rx_buf *rx_buf)
 
 772{
 773	unsigned int pagecnt_bias = rx_buf->pagecnt_bias;
 774	struct page *page = rx_buf->page;
 775
 776	/* avoid re-using remote pages */
 777	if (unlikely(ice_page_is_reserved(page)))
 778		return false;
 779
 780#if (PAGE_SIZE < 8192)
 781	/* if we are only owner of page we can reuse it */
 782	if (unlikely((page_count(page) - pagecnt_bias) > 1))
 783		return false;
 784#else
 785#define ICE_LAST_OFFSET \
 786	(SKB_WITH_OVERHEAD(PAGE_SIZE) - ICE_RXBUF_2048)
 787	if (rx_buf->page_offset > ICE_LAST_OFFSET)
 788		return false;
 789#endif /* PAGE_SIZE < 8192) */
 790
 791	/* If we have drained the page fragment pool we need to update
 792	 * the pagecnt_bias and page count so that we fully restock the
 793	 * number of references the driver holds.
 794	 */
 795	if (unlikely(pagecnt_bias == 1)) {
 796		page_ref_add(page, USHRT_MAX - 1);
 797		rx_buf->pagecnt_bias = USHRT_MAX;
 798	}
 799
 800	return true;
 801}
 802
 803/**
 804 * ice_add_rx_frag - Add contents of Rx buffer to sk_buff as a frag
 805 * @rx_ring: Rx descriptor ring to transact packets on
 806 * @rx_buf: buffer containing page to add
 807 * @skb: sk_buff to place the data into
 808 * @size: packet length from rx_desc
 809 *
 810 * This function will add the data contained in rx_buf->page to the skb.
 811 * It will just attach the page as a frag to the skb.
 812 * The function will then update the page offset.
 813 */
 814static void
 815ice_add_rx_frag(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
 816		struct sk_buff *skb, unsigned int size)
 817{
 818#if (PAGE_SIZE >= 8192)
 819	unsigned int truesize = SKB_DATA_ALIGN(size + ice_rx_offset(rx_ring));
 820#else
 821	unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
 822#endif
 823
 824	if (!size)
 825		return;
 826	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buf->page,
 827			rx_buf->page_offset, size, truesize);
 828
 829	/* page is being used so we must update the page offset */
 830	ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
 831}
 832
 833/**
 834 * ice_reuse_rx_page - page flip buffer and store it back on the ring
 835 * @rx_ring: Rx descriptor ring to store buffers on
 836 * @old_buf: donor buffer to have page reused
 837 *
 838 * Synchronizes page for reuse by the adapter
 839 */
 840static void
 841ice_reuse_rx_page(struct ice_ring *rx_ring, struct ice_rx_buf *old_buf)
 842{
 843	u16 nta = rx_ring->next_to_alloc;
 844	struct ice_rx_buf *new_buf;
 845
 846	new_buf = &rx_ring->rx_buf[nta];
 847
 848	/* update, and store next to alloc */
 849	nta++;
 850	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 851
 852	/* Transfer page from old buffer to new buffer.
 853	 * Move each member individually to avoid possible store
 854	 * forwarding stalls and unnecessary copy of skb.
 855	 */
 856	new_buf->dma = old_buf->dma;
 857	new_buf->page = old_buf->page;
 858	new_buf->page_offset = old_buf->page_offset;
 859	new_buf->pagecnt_bias = old_buf->pagecnt_bias;
 860}
 861
 862/**
 863 * ice_get_rx_buf - Fetch Rx buffer and synchronize data for use
 864 * @rx_ring: Rx descriptor ring to transact packets on
 865 * @skb: skb to be used
 866 * @size: size of buffer to add to skb
 
 867 *
 868 * This function will pull an Rx buffer from the ring and synchronize it
 869 * for use by the CPU.
 870 */
 871static struct ice_rx_buf *
 872ice_get_rx_buf(struct ice_ring *rx_ring, struct sk_buff **skb,
 873	       const unsigned int size)
 874{
 875	struct ice_rx_buf *rx_buf;
 876
 877	rx_buf = &rx_ring->rx_buf[rx_ring->next_to_clean];
 
 
 
 
 
 
 878	prefetchw(rx_buf->page);
 879	*skb = rx_buf->skb;
 880
 881	if (!size)
 882		return rx_buf;
 883	/* we are reusing so sync this buffer for CPU use */
 884	dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
 885				      rx_buf->page_offset, size,
 886				      DMA_FROM_DEVICE);
 887
 888	/* We have pulled a buffer for use, so decrement pagecnt_bias */
 889	rx_buf->pagecnt_bias--;
 890
 891	return rx_buf;
 892}
 893
 894/**
 895 * ice_build_skb - Build skb around an existing buffer
 896 * @rx_ring: Rx descriptor ring to transact packets on
 897 * @rx_buf: Rx buffer to pull data from
 898 * @xdp: xdp_buff pointing to the data
 899 *
 900 * This function builds an skb around an existing Rx buffer, taking care
 901 * to set up the skb correctly and avoid any memcpy overhead.
 902 */
 903static struct sk_buff *
 904ice_build_skb(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
 905	      struct xdp_buff *xdp)
 906{
 907	u8 metasize = xdp->data - xdp->data_meta;
 908#if (PAGE_SIZE < 8192)
 909	unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
 910#else
 911	unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
 912				SKB_DATA_ALIGN(xdp->data_end -
 913					       xdp->data_hard_start);
 914#endif
 915	struct sk_buff *skb;
 916
 917	/* Prefetch first cache line of first page. If xdp->data_meta
 918	 * is unused, this points exactly as xdp->data, otherwise we
 919	 * likely have a consumer accessing first few bytes of meta
 920	 * data, and then actual data.
 921	 */
 922	prefetch(xdp->data_meta);
 923#if L1_CACHE_BYTES < 128
 924	prefetch((void *)(xdp->data + L1_CACHE_BYTES));
 925#endif
 926	/* build an skb around the page buffer */
 927	skb = build_skb(xdp->data_hard_start, truesize);
 928	if (unlikely(!skb))
 929		return NULL;
 930
 931	/* must to record Rx queue, otherwise OS features such as
 932	 * symmetric queue won't work
 933	 */
 934	skb_record_rx_queue(skb, rx_ring->q_index);
 935
 936	/* update pointers within the skb to store the data */
 937	skb_reserve(skb, xdp->data - xdp->data_hard_start);
 938	__skb_put(skb, xdp->data_end - xdp->data);
 939	if (metasize)
 940		skb_metadata_set(skb, metasize);
 941
 942	/* buffer is used by skb, update page_offset */
 943	ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
 944
 945	return skb;
 946}
 947
 948/**
 949 * ice_construct_skb - Allocate skb and populate it
 950 * @rx_ring: Rx descriptor ring to transact packets on
 951 * @rx_buf: Rx buffer to pull data from
 952 * @xdp: xdp_buff pointing to the data
 953 *
 954 * This function allocates an skb. It then populates it with the page
 955 * data from the current receive descriptor, taking care to set up the
 956 * skb correctly.
 957 */
 958static struct sk_buff *
 959ice_construct_skb(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf,
 960		  struct xdp_buff *xdp)
 961{
 
 962	unsigned int size = xdp->data_end - xdp->data;
 963	unsigned int headlen;
 964	struct sk_buff *skb;
 965
 966	/* prefetch first cache line of first page */
 967	prefetch(xdp->data);
 968#if L1_CACHE_BYTES < 128
 969	prefetch((void *)(xdp->data + L1_CACHE_BYTES));
 970#endif /* L1_CACHE_BYTES */
 971
 972	/* allocate a skb to store the frags */
 973	skb = __napi_alloc_skb(&rx_ring->q_vector->napi, ICE_RX_HDR_SIZE,
 
 974			       GFP_ATOMIC | __GFP_NOWARN);
 975	if (unlikely(!skb))
 976		return NULL;
 977
 978	skb_record_rx_queue(skb, rx_ring->q_index);
 979	/* Determine available headroom for copy */
 980	headlen = size;
 981	if (headlen > ICE_RX_HDR_SIZE)
 982		headlen = eth_get_headlen(skb->dev, xdp->data, ICE_RX_HDR_SIZE);
 983
 984	/* align pull length to size of long to optimize memcpy performance */
 985	memcpy(__skb_put(skb, headlen), xdp->data, ALIGN(headlen,
 986							 sizeof(long)));
 
 
 
 
 
 987
 988	/* if we exhaust the linear part then add what is left as a frag */
 989	size -= headlen;
 990	if (size) {
 991#if (PAGE_SIZE >= 8192)
 992		unsigned int truesize = SKB_DATA_ALIGN(size);
 993#else
 994		unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
 995#endif
 996		skb_add_rx_frag(skb, 0, rx_buf->page,
 997				rx_buf->page_offset + headlen, size, truesize);
 998		/* buffer is used by skb, update page_offset */
 999		ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
1000	} else {
1001		/* buffer is unused, reset bias back to rx_buf; data was copied
1002		 * onto skb's linear part so there's no need for adjusting
1003		 * page offset and we can reuse this buffer as-is
1004		 */
1005		rx_buf->pagecnt_bias++;
1006	}
1007
1008	return skb;
1009}
1010
1011/**
1012 * ice_put_rx_buf - Clean up used buffer and either recycle or free
1013 * @rx_ring: Rx descriptor ring to transact packets on
1014 * @rx_buf: Rx buffer to pull data from
 
1015 *
1016 * This function will update next_to_clean and then clean up the contents
1017 * of the rx_buf. It will either recycle the buffer or unmap it and free
1018 * the associated resources.
1019 */
1020static void ice_put_rx_buf(struct ice_ring *rx_ring, struct ice_rx_buf *rx_buf)
 
 
1021{
1022	u16 ntc = rx_ring->next_to_clean + 1;
1023
1024	/* fetch, update, and store next to clean */
1025	ntc = (ntc < rx_ring->count) ? ntc : 0;
1026	rx_ring->next_to_clean = ntc;
1027
1028	if (!rx_buf)
1029		return;
1030
1031	if (ice_can_reuse_rx_page(rx_buf)) {
1032		/* hand second half of page back to the ring */
1033		ice_reuse_rx_page(rx_ring, rx_buf);
1034	} else {
1035		/* we are not reusing the buffer so unmap it */
1036		dma_unmap_page_attrs(rx_ring->dev, rx_buf->dma,
1037				     ice_rx_pg_size(rx_ring), DMA_FROM_DEVICE,
1038				     ICE_RX_DMA_ATTR);
1039		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
1040	}
1041
1042	/* clear contents of buffer_info */
1043	rx_buf->page = NULL;
1044	rx_buf->skb = NULL;
1045}
1046
1047/**
1048 * ice_is_non_eop - process handling of non-EOP buffers
1049 * @rx_ring: Rx ring being processed
1050 * @rx_desc: Rx descriptor for current buffer
1051 * @skb: Current socket buffer containing buffer in progress
1052 *
1053 * If the buffer is an EOP buffer, this function exits returning false,
1054 * otherwise return true indicating that this is in fact a non-EOP buffer.
1055 */
1056static bool
1057ice_is_non_eop(struct ice_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc,
1058	       struct sk_buff *skb)
1059{
1060	/* if we are the last buffer then there is nothing else to do */
1061#define ICE_RXD_EOF BIT(ICE_RX_FLEX_DESC_STATUS0_EOF_S)
1062	if (likely(ice_test_staterr(rx_desc, ICE_RXD_EOF)))
1063		return false;
1064
1065	/* place skb in next buffer to be received */
1066	rx_ring->rx_buf[rx_ring->next_to_clean].skb = skb;
1067	rx_ring->rx_stats.non_eop_descs++;
1068
1069	return true;
1070}
1071
1072/**
1073 * ice_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
1074 * @rx_ring: Rx descriptor ring to transact packets on
1075 * @budget: Total limit on number of packets to process
1076 *
1077 * This function provides a "bounce buffer" approach to Rx interrupt
1078 * processing. The advantage to this is that on systems that have
1079 * expensive overhead for IOMMU access this provides a means of avoiding
1080 * it by maintaining the mapping of the page to the system.
1081 *
1082 * Returns amount of work completed
1083 */
1084int ice_clean_rx_irq(struct ice_ring *rx_ring, int budget)
1085{
1086	unsigned int total_rx_bytes = 0, total_rx_pkts = 0;
1087	u16 cleaned_count = ICE_DESC_UNUSED(rx_ring);
 
 
1088	unsigned int xdp_res, xdp_xmit = 0;
 
1089	struct bpf_prog *xdp_prog = NULL;
1090	struct xdp_buff xdp;
1091	bool failure;
1092
1093	xdp.rxq = &rx_ring->xdp_rxq;
1094	/* Frame size depend on rx_ring setup when PAGE_SIZE=4K */
1095#if (PAGE_SIZE < 8192)
1096	xdp.frame_sz = ice_rx_frame_truesize(rx_ring, 0);
1097#endif
 
 
 
 
 
1098
1099	/* start the loop to process Rx packets bounded by 'budget' */
1100	while (likely(total_rx_pkts < (unsigned int)budget)) {
1101		union ice_32b_rx_flex_desc *rx_desc;
1102		struct ice_rx_buf *rx_buf;
1103		struct sk_buff *skb;
1104		unsigned int size;
1105		u16 stat_err_bits;
 
1106		u16 vlan_tag = 0;
1107		u8 rx_ptype;
1108
1109		/* get the Rx desc from Rx ring based on 'next_to_clean' */
1110		rx_desc = ICE_RX_DESC(rx_ring, rx_ring->next_to_clean);
1111
1112		/* status_error_len will always be zero for unused descriptors
1113		 * because it's cleared in cleanup, and overlaps with hdr_addr
1114		 * which is always zero because packet split isn't used, if the
1115		 * hardware wrote DD then it will be non-zero
1116		 */
1117		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_DD_S);
1118		if (!ice_test_staterr(rx_desc, stat_err_bits))
1119			break;
1120
1121		/* This memory barrier is needed to keep us from reading
1122		 * any other fields out of the rx_desc until we know the
1123		 * DD bit is set.
1124		 */
1125		dma_rmb();
1126
 
1127		if (rx_desc->wb.rxdid == FDIR_DESC_RXDID || !rx_ring->netdev) {
1128			ice_put_rx_buf(rx_ring, NULL);
 
 
 
 
 
1129			cleaned_count++;
1130			continue;
1131		}
1132
1133		size = le16_to_cpu(rx_desc->wb.pkt_len) &
1134			ICE_RX_FLX_DESC_PKT_LEN_M;
1135
1136		/* retrieve a buffer from the ring */
1137		rx_buf = ice_get_rx_buf(rx_ring, &skb, size);
1138
1139		if (!size) {
1140			xdp.data = NULL;
1141			xdp.data_end = NULL;
1142			xdp.data_hard_start = NULL;
1143			xdp.data_meta = NULL;
1144			goto construct_skb;
1145		}
1146
1147		xdp.data = page_address(rx_buf->page) + rx_buf->page_offset;
1148		xdp.data_hard_start = xdp.data - ice_rx_offset(rx_ring);
1149		xdp.data_meta = xdp.data;
1150		xdp.data_end = xdp.data + size;
1151#if (PAGE_SIZE > 4096)
1152		/* At larger PAGE_SIZE, frame_sz depend on len size */
1153		xdp.frame_sz = ice_rx_frame_truesize(rx_ring, size);
1154#endif
1155
1156		rcu_read_lock();
1157		xdp_prog = READ_ONCE(rx_ring->xdp_prog);
1158		if (!xdp_prog) {
1159			rcu_read_unlock();
1160			goto construct_skb;
1161		}
1162
1163		xdp_res = ice_run_xdp(rx_ring, &xdp, xdp_prog);
1164		rcu_read_unlock();
1165		if (!xdp_res)
1166			goto construct_skb;
1167		if (xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR)) {
1168			xdp_xmit |= xdp_res;
1169			ice_rx_buf_adjust_pg_offset(rx_buf, xdp.frame_sz);
1170		} else {
1171			rx_buf->pagecnt_bias++;
1172		}
1173		total_rx_bytes += size;
1174		total_rx_pkts++;
1175
1176		cleaned_count++;
1177		ice_put_rx_buf(rx_ring, rx_buf);
1178		continue;
1179construct_skb:
1180		if (skb) {
1181			ice_add_rx_frag(rx_ring, rx_buf, skb, size);
1182		} else if (likely(xdp.data)) {
1183			if (ice_ring_uses_build_skb(rx_ring))
1184				skb = ice_build_skb(rx_ring, rx_buf, &xdp);
1185			else
1186				skb = ice_construct_skb(rx_ring, rx_buf, &xdp);
1187		}
1188		/* exit if we failed to retrieve a buffer */
1189		if (!skb) {
1190			rx_ring->rx_stats.alloc_buf_failed++;
1191			if (rx_buf)
1192				rx_buf->pagecnt_bias++;
1193			break;
1194		}
1195
1196		ice_put_rx_buf(rx_ring, rx_buf);
1197		cleaned_count++;
1198
1199		/* skip if it is NOP desc */
1200		if (ice_is_non_eop(rx_ring, rx_desc, skb))
1201			continue;
1202
1203		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_RXE_S);
1204		if (unlikely(ice_test_staterr(rx_desc, stat_err_bits))) {
 
1205			dev_kfree_skb_any(skb);
1206			continue;
1207		}
1208
1209		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_L2TAG1P_S);
1210		if (ice_test_staterr(rx_desc, stat_err_bits))
1211			vlan_tag = le16_to_cpu(rx_desc->wb.l2tag1);
1212
1213		/* pad the skb if needed, to make a valid ethernet frame */
1214		if (eth_skb_pad(skb)) {
1215			skb = NULL;
1216			continue;
1217		}
1218
1219		/* probably a little skewed due to removing CRC */
1220		total_rx_bytes += skb->len;
1221
1222		/* populate checksum, VLAN, and protocol */
1223		rx_ptype = le16_to_cpu(rx_desc->wb.ptype_flex_flags0) &
1224			ICE_RX_FLEX_DESC_PTYPE_M;
1225
1226		ice_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
1227
 
1228		/* send completed skb up the stack */
1229		ice_receive_skb(rx_ring, skb, vlan_tag);
 
1230
1231		/* update budget accounting */
1232		total_rx_pkts++;
1233	}
1234
1235	/* return up to cleaned_count buffers to hardware */
1236	failure = ice_alloc_rx_bufs(rx_ring, cleaned_count);
1237
1238	if (xdp_prog)
1239		ice_finalize_xdp_rx(rx_ring, xdp_xmit);
 
1240
1241	ice_update_rx_ring_stats(rx_ring, total_rx_pkts, total_rx_bytes);
 
 
1242
1243	/* guarantee a trip back through this routine if there was a failure */
1244	return failure ? budget : (int)total_rx_pkts;
1245}
1246
1247/**
1248 * ice_adjust_itr_by_size_and_speed - Adjust ITR based on current traffic
1249 * @port_info: port_info structure containing the current link speed
1250 * @avg_pkt_size: average size of Tx or Rx packets based on clean routine
1251 * @itr: ITR value to update
1252 *
1253 * Calculate how big of an increment should be applied to the ITR value passed
1254 * in based on wmem_default, SKB overhead, ethernet overhead, and the current
1255 * link speed.
1256 *
1257 * The following is a calculation derived from:
1258 *  wmem_default / (size + overhead) = desired_pkts_per_int
1259 *  rate / bits_per_byte / (size + ethernet overhead) = pkt_rate
1260 *  (desired_pkt_rate / pkt_rate) * usecs_per_sec = ITR value
1261 *
1262 * Assuming wmem_default is 212992 and overhead is 640 bytes per
1263 * packet, (256 skb, 64 headroom, 320 shared info), we can reduce the
1264 * formula down to:
1265 *
1266 *	 wmem_default * bits_per_byte * usecs_per_sec   pkt_size + 24
1267 * ITR = -------------------------------------------- * --------------
1268 *			     rate			pkt_size + 640
1269 */
1270static unsigned int
1271ice_adjust_itr_by_size_and_speed(struct ice_port_info *port_info,
1272				 unsigned int avg_pkt_size,
1273				 unsigned int itr)
1274{
1275	switch (port_info->phy.link_info.link_speed) {
1276	case ICE_AQ_LINK_SPEED_100GB:
1277		itr += DIV_ROUND_UP(17 * (avg_pkt_size + 24),
1278				    avg_pkt_size + 640);
1279		break;
1280	case ICE_AQ_LINK_SPEED_50GB:
1281		itr += DIV_ROUND_UP(34 * (avg_pkt_size + 24),
1282				    avg_pkt_size + 640);
1283		break;
1284	case ICE_AQ_LINK_SPEED_40GB:
1285		itr += DIV_ROUND_UP(43 * (avg_pkt_size + 24),
1286				    avg_pkt_size + 640);
1287		break;
1288	case ICE_AQ_LINK_SPEED_25GB:
1289		itr += DIV_ROUND_UP(68 * (avg_pkt_size + 24),
1290				    avg_pkt_size + 640);
1291		break;
1292	case ICE_AQ_LINK_SPEED_20GB:
1293		itr += DIV_ROUND_UP(85 * (avg_pkt_size + 24),
1294				    avg_pkt_size + 640);
1295		break;
1296	case ICE_AQ_LINK_SPEED_10GB:
1297	default:
1298		itr += DIV_ROUND_UP(170 * (avg_pkt_size + 24),
1299				    avg_pkt_size + 640);
1300		break;
1301	}
1302
1303	if ((itr & ICE_ITR_MASK) > ICE_ITR_ADAPTIVE_MAX_USECS) {
1304		itr &= ICE_ITR_ADAPTIVE_LATENCY;
1305		itr += ICE_ITR_ADAPTIVE_MAX_USECS;
 
 
 
1306	}
1307
1308	return itr;
 
 
 
 
 
 
 
 
 
1309}
1310
1311/**
1312 * ice_update_itr - update the adaptive ITR value based on statistics
1313 * @q_vector: structure containing interrupt and ring information
1314 * @rc: structure containing ring performance data
1315 *
1316 * Stores a new ITR value based on packets and byte
1317 * counts during the last interrupt.  The advantage of per interrupt
1318 * computation is faster updates and more accurate ITR for the current
1319 * traffic pattern.  Constants in this function were computed
1320 * based on theoretical maximum wire speed and thresholds were set based
1321 * on testing data as well as attempting to minimize response time
1322 * while increasing bulk throughput.
1323 */
1324static void
1325ice_update_itr(struct ice_q_vector *q_vector, struct ice_ring_container *rc)
1326{
1327	unsigned long next_update = jiffies;
1328	unsigned int packets, bytes, itr;
1329	bool container_is_rx;
1330
1331	if (!rc->ring || !ITR_IS_DYNAMIC(rc->itr_setting))
1332		return;
1333
1334	/* If itr_countdown is set it means we programmed an ITR within
1335	 * the last 4 interrupt cycles. This has a side effect of us
1336	 * potentially firing an early interrupt. In order to work around
1337	 * this we need to throw out any data received for a few
1338	 * interrupts following the update.
1339	 */
1340	if (q_vector->itr_countdown) {
1341		itr = rc->target_itr;
1342		goto clear_counts;
1343	}
1344
1345	container_is_rx = (&q_vector->rx == rc);
1346	/* For Rx we want to push the delay up and default to low latency.
1347	 * for Tx we want to pull the delay down and default to high latency.
1348	 */
1349	itr = container_is_rx ?
1350		ICE_ITR_ADAPTIVE_MIN_USECS | ICE_ITR_ADAPTIVE_LATENCY :
1351		ICE_ITR_ADAPTIVE_MAX_USECS | ICE_ITR_ADAPTIVE_LATENCY;
1352
1353	/* If we didn't update within up to 1 - 2 jiffies we can assume
1354	 * that either packets are coming in so slow there hasn't been
1355	 * any work, or that there is so much work that NAPI is dealing
1356	 * with interrupt moderation and we don't need to do anything.
1357	 */
1358	if (time_after(next_update, rc->next_update))
1359		goto clear_counts;
1360
1361	prefetch(q_vector->vsi->port_info);
1362
1363	packets = rc->total_pkts;
1364	bytes = rc->total_bytes;
1365
1366	if (container_is_rx) {
1367		/* If Rx there are 1 to 4 packets and bytes are less than
1368		 * 9000 assume insufficient data to use bulk rate limiting
1369		 * approach unless Tx is already in bulk rate limiting. We
1370		 * are likely latency driven.
1371		 */
1372		if (packets && packets < 4 && bytes < 9000 &&
1373		    (q_vector->tx.target_itr & ICE_ITR_ADAPTIVE_LATENCY)) {
1374			itr = ICE_ITR_ADAPTIVE_LATENCY;
1375			goto adjust_by_size_and_speed;
1376		}
1377	} else if (packets < 4) {
1378		/* If we have Tx and Rx ITR maxed and Tx ITR is running in
1379		 * bulk mode and we are receiving 4 or fewer packets just
1380		 * reset the ITR_ADAPTIVE_LATENCY bit for latency mode so
1381		 * that the Rx can relax.
1382		 */
1383		if (rc->target_itr == ICE_ITR_ADAPTIVE_MAX_USECS &&
1384		    (q_vector->rx.target_itr & ICE_ITR_MASK) ==
1385		    ICE_ITR_ADAPTIVE_MAX_USECS)
1386			goto clear_counts;
1387	} else if (packets > 32) {
1388		/* If we have processed over 32 packets in a single interrupt
1389		 * for Tx assume we need to switch over to "bulk" mode.
1390		 */
1391		rc->target_itr &= ~ICE_ITR_ADAPTIVE_LATENCY;
1392	}
1393
1394	/* We have no packets to actually measure against. This means
1395	 * either one of the other queues on this vector is active or
1396	 * we are a Tx queue doing TSO with too high of an interrupt rate.
1397	 *
1398	 * Between 4 and 56 we can assume that our current interrupt delay
1399	 * is only slightly too low. As such we should increase it by a small
1400	 * fixed amount.
1401	 */
1402	if (packets < 56) {
1403		itr = rc->target_itr + ICE_ITR_ADAPTIVE_MIN_INC;
1404		if ((itr & ICE_ITR_MASK) > ICE_ITR_ADAPTIVE_MAX_USECS) {
1405			itr &= ICE_ITR_ADAPTIVE_LATENCY;
1406			itr += ICE_ITR_ADAPTIVE_MAX_USECS;
1407		}
1408		goto clear_counts;
1409	}
1410
1411	if (packets <= 256) {
1412		itr = min(q_vector->tx.current_itr, q_vector->rx.current_itr);
1413		itr &= ICE_ITR_MASK;
1414
1415		/* Between 56 and 112 is our "goldilocks" zone where we are
1416		 * working out "just right". Just report that our current
1417		 * ITR is good for us.
1418		 */
1419		if (packets <= 112)
1420			goto clear_counts;
1421
1422		/* If packet count is 128 or greater we are likely looking
1423		 * at a slight overrun of the delay we want. Try halving
1424		 * our delay to see if that will cut the number of packets
1425		 * in half per interrupt.
1426		 */
1427		itr >>= 1;
1428		itr &= ICE_ITR_MASK;
1429		if (itr < ICE_ITR_ADAPTIVE_MIN_USECS)
1430			itr = ICE_ITR_ADAPTIVE_MIN_USECS;
1431
1432		goto clear_counts;
1433	}
1434
1435	/* The paths below assume we are dealing with a bulk ITR since
1436	 * number of packets is greater than 256. We are just going to have
1437	 * to compute a value and try to bring the count under control,
1438	 * though for smaller packet sizes there isn't much we can do as
1439	 * NAPI polling will likely be kicking in sooner rather than later.
1440	 */
1441	itr = ICE_ITR_ADAPTIVE_BULK;
1442
1443adjust_by_size_and_speed:
1444
1445	/* based on checks above packets cannot be 0 so division is safe */
1446	itr = ice_adjust_itr_by_size_and_speed(q_vector->vsi->port_info,
1447					       bytes / packets, itr);
1448
1449clear_counts:
1450	/* write back value */
1451	rc->target_itr = itr;
1452
1453	/* next update should occur within next jiffy */
1454	rc->next_update = next_update + 1;
1455
1456	rc->total_bytes = 0;
1457	rc->total_pkts = 0;
1458}
1459
1460/**
1461 * ice_buildreg_itr - build value for writing to the GLINT_DYN_CTL register
1462 * @itr_idx: interrupt throttling index
1463 * @itr: interrupt throttling value in usecs
1464 */
1465static u32 ice_buildreg_itr(u16 itr_idx, u16 itr)
1466{
1467	/* The ITR value is reported in microseconds, and the register value is
1468	 * recorded in 2 microsecond units. For this reason we only need to
1469	 * shift by the GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S to apply this
1470	 * granularity as a shift instead of division. The mask makes sure the
1471	 * ITR value is never odd so we don't accidentally write into the field
1472	 * prior to the ITR field.
1473	 */
1474	itr &= ICE_ITR_MASK;
1475
1476	return GLINT_DYN_CTL_INTENA_M | GLINT_DYN_CTL_CLEARPBA_M |
1477		(itr_idx << GLINT_DYN_CTL_ITR_INDX_S) |
1478		(itr << (GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S));
1479}
1480
1481/* The act of updating the ITR will cause it to immediately trigger. In order
1482 * to prevent this from throwing off adaptive update statistics we defer the
1483 * update so that it can only happen so often. So after either Tx or Rx are
1484 * updated we make the adaptive scheme wait until either the ITR completely
1485 * expires via the next_update expiration or we have been through at least
1486 * 3 interrupts.
1487 */
1488#define ITR_COUNTDOWN_START 3
1489
1490/**
1491 * ice_update_ena_itr - Update ITR and re-enable MSIX interrupt
1492 * @q_vector: q_vector for which ITR is being updated and interrupt enabled
 
 
 
 
1493 */
1494static void ice_update_ena_itr(struct ice_q_vector *q_vector)
1495{
1496	struct ice_ring_container *tx = &q_vector->tx;
1497	struct ice_ring_container *rx = &q_vector->rx;
1498	struct ice_vsi *vsi = q_vector->vsi;
 
1499	u32 itr_val;
1500
1501	/* when exiting WB_ON_ITR lets set a low ITR value and trigger
1502	 * interrupts to expire right away in case we have more work ready to go
1503	 * already
1504	 */
1505	if (q_vector->itr_countdown == ICE_IN_WB_ON_ITR_MODE) {
1506		itr_val = ice_buildreg_itr(rx->itr_idx, ICE_WB_ON_ITR_USECS);
1507		wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
1508		/* set target back to last user set value */
1509		rx->target_itr = rx->itr_setting;
1510		/* set current to what we just wrote and dynamic if needed */
1511		rx->current_itr = ICE_WB_ON_ITR_USECS |
1512			(rx->itr_setting & ICE_ITR_DYNAMIC);
1513		/* allow normal interrupt flow to start */
1514		q_vector->itr_countdown = 0;
1515		return;
1516	}
1517
1518	/* This will do nothing if dynamic updates are not enabled */
1519	ice_update_itr(q_vector, tx);
1520	ice_update_itr(q_vector, rx);
1521
1522	/* This block of logic allows us to get away with only updating
1523	 * one ITR value with each interrupt. The idea is to perform a
1524	 * pseudo-lazy update with the following criteria.
1525	 *
1526	 * 1. Rx is given higher priority than Tx if both are in same state
1527	 * 2. If we must reduce an ITR that is given highest priority.
1528	 * 3. We then give priority to increasing ITR based on amount.
1529	 */
1530	if (rx->target_itr < rx->current_itr) {
1531		/* Rx ITR needs to be reduced, this is highest priority */
1532		itr_val = ice_buildreg_itr(rx->itr_idx, rx->target_itr);
1533		rx->current_itr = rx->target_itr;
1534		q_vector->itr_countdown = ITR_COUNTDOWN_START;
1535	} else if ((tx->target_itr < tx->current_itr) ||
1536		   ((rx->target_itr - rx->current_itr) <
1537		    (tx->target_itr - tx->current_itr))) {
1538		/* Tx ITR needs to be reduced, this is second priority
1539		 * Tx ITR needs to be increased more than Rx, fourth priority
1540		 */
1541		itr_val = ice_buildreg_itr(tx->itr_idx, tx->target_itr);
1542		tx->current_itr = tx->target_itr;
1543		q_vector->itr_countdown = ITR_COUNTDOWN_START;
1544	} else if (rx->current_itr != rx->target_itr) {
1545		/* Rx ITR needs to be increased, third priority */
1546		itr_val = ice_buildreg_itr(rx->itr_idx, rx->target_itr);
1547		rx->current_itr = rx->target_itr;
1548		q_vector->itr_countdown = ITR_COUNTDOWN_START;
1549	} else {
1550		/* Still have to re-enable the interrupts */
1551		itr_val = ice_buildreg_itr(ICE_ITR_NONE, 0);
1552		if (q_vector->itr_countdown)
1553			q_vector->itr_countdown--;
1554	}
1555
1556	if (!test_bit(__ICE_DOWN, q_vector->vsi->state))
1557		wr32(&q_vector->vsi->back->hw,
1558		     GLINT_DYN_CTL(q_vector->reg_idx),
1559		     itr_val);
 
 
 
 
 
 
 
 
1560}
1561
1562/**
1563 * ice_set_wb_on_itr - set WB_ON_ITR for this q_vector
1564 * @q_vector: q_vector to set WB_ON_ITR on
1565 *
1566 * We need to tell hardware to write-back completed descriptors even when
1567 * interrupts are disabled. Descriptors will be written back on cache line
1568 * boundaries without WB_ON_ITR enabled, but if we don't enable WB_ON_ITR
1569 * descriptors may not be written back if they don't fill a cache line until the
1570 * next interrupt.
1571 *
1572 * This sets the write-back frequency to 2 microseconds as that is the minimum
1573 * value that's not 0 due to ITR granularity. Also, set the INTENA_MSK bit to
1574 * make sure hardware knows we aren't meddling with the INTENA_M bit.
1575 */
1576static void ice_set_wb_on_itr(struct ice_q_vector *q_vector)
1577{
1578	struct ice_vsi *vsi = q_vector->vsi;
1579
1580	/* already in WB_ON_ITR mode no need to change it */
1581	if (q_vector->itr_countdown == ICE_IN_WB_ON_ITR_MODE)
1582		return;
1583
1584	if (q_vector->num_ring_rx)
1585		wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1586		     ICE_GLINT_DYN_CTL_WB_ON_ITR(ICE_WB_ON_ITR_USECS,
1587						 ICE_RX_ITR));
1588
1589	if (q_vector->num_ring_tx)
1590		wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1591		     ICE_GLINT_DYN_CTL_WB_ON_ITR(ICE_WB_ON_ITR_USECS,
1592						 ICE_TX_ITR));
1593
1594	q_vector->itr_countdown = ICE_IN_WB_ON_ITR_MODE;
1595}
1596
1597/**
1598 * ice_napi_poll - NAPI polling Rx/Tx cleanup routine
1599 * @napi: napi struct with our devices info in it
1600 * @budget: amount of work driver is allowed to do this pass, in packets
1601 *
1602 * This function will clean all queues associated with a q_vector.
1603 *
1604 * Returns the amount of work done
1605 */
1606int ice_napi_poll(struct napi_struct *napi, int budget)
1607{
1608	struct ice_q_vector *q_vector =
1609				container_of(napi, struct ice_q_vector, napi);
 
 
1610	bool clean_complete = true;
1611	struct ice_ring *ring;
1612	int budget_per_ring;
1613	int work_done = 0;
1614
1615	/* Since the actual Tx work is minimal, we can give the Tx a larger
1616	 * budget and be more aggressive about cleaning up the Tx descriptors.
1617	 */
1618	ice_for_each_ring(ring, q_vector->tx) {
1619		bool wd = ring->xsk_umem ?
1620			  ice_clean_tx_irq_zc(ring, budget) :
1621			  ice_clean_tx_irq(ring, budget);
 
 
 
 
 
1622
1623		if (!wd)
1624			clean_complete = false;
1625	}
1626
1627	/* Handle case where we are called by netpoll with a budget of 0 */
1628	if (unlikely(budget <= 0))
1629		return budget;
1630
1631	/* normally we have 1 Rx ring per q_vector */
1632	if (unlikely(q_vector->num_ring_rx > 1))
1633		/* We attempt to distribute budget to each Rx queue fairly, but
1634		 * don't allow the budget to go below 1 because that would exit
1635		 * polling early.
1636		 */
1637		budget_per_ring = max_t(int, budget / q_vector->num_ring_rx, 1);
1638	else
1639		/* Max of 1 Rx ring in this q_vector so give it the budget */
1640		budget_per_ring = budget;
1641
1642	ice_for_each_ring(ring, q_vector->rx) {
1643		int cleaned;
1644
1645		/* A dedicated path for zero-copy allows making a single
1646		 * comparison in the irq context instead of many inside the
1647		 * ice_clean_rx_irq function and makes the codebase cleaner.
1648		 */
1649		cleaned = ring->xsk_umem ?
1650			  ice_clean_rx_irq_zc(ring, budget_per_ring) :
1651			  ice_clean_rx_irq(ring, budget_per_ring);
1652		work_done += cleaned;
1653		/* if we clean as many as budgeted, we must not be done */
1654		if (cleaned >= budget_per_ring)
1655			clean_complete = false;
1656	}
1657
1658	/* If work not completed, return budget and polling will return */
1659	if (!clean_complete)
 
 
 
 
1660		return budget;
 
1661
1662	/* Exit the polling mode, but don't re-enable interrupts if stack might
1663	 * poll us due to busy-polling
1664	 */
1665	if (likely(napi_complete_done(napi, work_done)))
1666		ice_update_ena_itr(q_vector);
1667	else
 
1668		ice_set_wb_on_itr(q_vector);
 
1669
1670	return min_t(int, work_done, budget - 1);
1671}
1672
1673/**
1674 * __ice_maybe_stop_tx - 2nd level check for Tx stop conditions
1675 * @tx_ring: the ring to be checked
1676 * @size: the size buffer we want to assure is available
1677 *
1678 * Returns -EBUSY if a stop is needed, else 0
1679 */
1680static int __ice_maybe_stop_tx(struct ice_ring *tx_ring, unsigned int size)
1681{
1682	netif_stop_subqueue(tx_ring->netdev, tx_ring->q_index);
1683	/* Memory barrier before checking head and tail */
1684	smp_mb();
1685
1686	/* Check again in a case another CPU has just made room available. */
1687	if (likely(ICE_DESC_UNUSED(tx_ring) < size))
1688		return -EBUSY;
1689
1690	/* A reprieve! - use start_subqueue because it doesn't call schedule */
1691	netif_start_subqueue(tx_ring->netdev, tx_ring->q_index);
1692	++tx_ring->tx_stats.restart_q;
1693	return 0;
1694}
1695
1696/**
1697 * ice_maybe_stop_tx - 1st level check for Tx stop conditions
1698 * @tx_ring: the ring to be checked
1699 * @size:    the size buffer we want to assure is available
1700 *
1701 * Returns 0 if stop is not needed
1702 */
1703static int ice_maybe_stop_tx(struct ice_ring *tx_ring, unsigned int size)
1704{
1705	if (likely(ICE_DESC_UNUSED(tx_ring) >= size))
1706		return 0;
1707
1708	return __ice_maybe_stop_tx(tx_ring, size);
1709}
1710
1711/**
1712 * ice_tx_map - Build the Tx descriptor
1713 * @tx_ring: ring to send buffer on
1714 * @first: first buffer info buffer to use
1715 * @off: pointer to struct that holds offload parameters
1716 *
1717 * This function loops over the skb data pointed to by *first
1718 * and gets a physical address for each memory location and programs
1719 * it and the length into the transmit descriptor.
1720 */
1721static void
1722ice_tx_map(struct ice_ring *tx_ring, struct ice_tx_buf *first,
1723	   struct ice_tx_offload_params *off)
1724{
1725	u64 td_offset, td_tag, td_cmd;
1726	u16 i = tx_ring->next_to_use;
1727	unsigned int data_len, size;
1728	struct ice_tx_desc *tx_desc;
1729	struct ice_tx_buf *tx_buf;
1730	struct sk_buff *skb;
1731	skb_frag_t *frag;
1732	dma_addr_t dma;
 
1733
1734	td_tag = off->td_l2tag1;
1735	td_cmd = off->td_cmd;
1736	td_offset = off->td_offset;
1737	skb = first->skb;
1738
1739	data_len = skb->data_len;
1740	size = skb_headlen(skb);
1741
1742	tx_desc = ICE_TX_DESC(tx_ring, i);
1743
1744	if (first->tx_flags & ICE_TX_FLAGS_HW_VLAN) {
1745		td_cmd |= (u64)ICE_TX_DESC_CMD_IL2TAG1;
1746		td_tag = (first->tx_flags & ICE_TX_FLAGS_VLAN_M) >>
1747			  ICE_TX_FLAGS_VLAN_S;
1748	}
1749
1750	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1751
1752	tx_buf = first;
1753
1754	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1755		unsigned int max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1756
1757		if (dma_mapping_error(tx_ring->dev, dma))
1758			goto dma_error;
1759
1760		/* record length, and DMA address */
1761		dma_unmap_len_set(tx_buf, len, size);
1762		dma_unmap_addr_set(tx_buf, dma, dma);
1763
1764		/* align size to end of page */
1765		max_data += -dma & (ICE_MAX_READ_REQ_SIZE - 1);
1766		tx_desc->buf_addr = cpu_to_le64(dma);
1767
1768		/* account for data chunks larger than the hardware
1769		 * can handle
1770		 */
1771		while (unlikely(size > ICE_MAX_DATA_PER_TXD)) {
1772			tx_desc->cmd_type_offset_bsz =
1773				ice_build_ctob(td_cmd, td_offset, max_data,
1774					       td_tag);
1775
1776			tx_desc++;
1777			i++;
1778
1779			if (i == tx_ring->count) {
1780				tx_desc = ICE_TX_DESC(tx_ring, 0);
1781				i = 0;
1782			}
1783
1784			dma += max_data;
1785			size -= max_data;
1786
1787			max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1788			tx_desc->buf_addr = cpu_to_le64(dma);
1789		}
1790
1791		if (likely(!data_len))
1792			break;
1793
1794		tx_desc->cmd_type_offset_bsz = ice_build_ctob(td_cmd, td_offset,
1795							      size, td_tag);
1796
1797		tx_desc++;
1798		i++;
1799
1800		if (i == tx_ring->count) {
1801			tx_desc = ICE_TX_DESC(tx_ring, 0);
1802			i = 0;
1803		}
1804
1805		size = skb_frag_size(frag);
1806		data_len -= size;
1807
1808		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1809				       DMA_TO_DEVICE);
1810
1811		tx_buf = &tx_ring->tx_buf[i];
1812	}
1813
1814	/* record bytecount for BQL */
1815	netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount);
1816
1817	/* record SW timestamp if HW timestamp is not available */
1818	skb_tx_timestamp(first->skb);
1819
1820	i++;
1821	if (i == tx_ring->count)
1822		i = 0;
1823
1824	/* write last descriptor with RS and EOP bits */
1825	td_cmd |= (u64)ICE_TXD_LAST_DESC_CMD;
1826	tx_desc->cmd_type_offset_bsz =
1827			ice_build_ctob(td_cmd, td_offset, size, td_tag);
1828
1829	/* Force memory writes to complete before letting h/w know there
1830	 * are new descriptors to fetch.
1831	 *
1832	 * We also use this memory barrier to make certain all of the
1833	 * status bits have been updated before next_to_watch is written.
1834	 */
1835	wmb();
1836
1837	/* set next_to_watch value indicating a packet is present */
1838	first->next_to_watch = tx_desc;
1839
1840	tx_ring->next_to_use = i;
1841
1842	ice_maybe_stop_tx(tx_ring, DESC_NEEDED);
1843
1844	/* notify HW of packet */
1845	if (netif_xmit_stopped(txring_txq(tx_ring)) || !netdev_xmit_more())
 
 
 
1846		writel(i, tx_ring->tail);
1847
1848	return;
1849
1850dma_error:
1851	/* clear DMA mappings for failed tx_buf map */
1852	for (;;) {
1853		tx_buf = &tx_ring->tx_buf[i];
1854		ice_unmap_and_free_tx_buf(tx_ring, tx_buf);
1855		if (tx_buf == first)
1856			break;
1857		if (i == 0)
1858			i = tx_ring->count;
1859		i--;
1860	}
1861
1862	tx_ring->next_to_use = i;
1863}
1864
1865/**
1866 * ice_tx_csum - Enable Tx checksum offloads
1867 * @first: pointer to the first descriptor
1868 * @off: pointer to struct that holds offload parameters
1869 *
1870 * Returns 0 or error (negative) if checksum offload can't happen, 1 otherwise.
1871 */
1872static
1873int ice_tx_csum(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
1874{
1875	u32 l4_len = 0, l3_len = 0, l2_len = 0;
1876	struct sk_buff *skb = first->skb;
1877	union {
1878		struct iphdr *v4;
1879		struct ipv6hdr *v6;
1880		unsigned char *hdr;
1881	} ip;
1882	union {
1883		struct tcphdr *tcp;
1884		unsigned char *hdr;
1885	} l4;
1886	__be16 frag_off, protocol;
1887	unsigned char *exthdr;
1888	u32 offset, cmd = 0;
1889	u8 l4_proto = 0;
1890
1891	if (skb->ip_summed != CHECKSUM_PARTIAL)
1892		return 0;
1893
1894	ip.hdr = skb_network_header(skb);
1895	l4.hdr = skb_transport_header(skb);
 
 
 
 
 
 
 
1896
1897	/* compute outer L2 header size */
1898	l2_len = ip.hdr - skb->data;
1899	offset = (l2_len / 2) << ICE_TX_DESC_LEN_MACLEN_S;
1900
1901	protocol = vlan_get_protocol(skb);
1902
1903	if (protocol == htons(ETH_P_IP))
 
1904		first->tx_flags |= ICE_TX_FLAGS_IPV4;
1905	else if (protocol == htons(ETH_P_IPV6))
1906		first->tx_flags |= ICE_TX_FLAGS_IPV6;
1907
1908	if (skb->encapsulation) {
1909		bool gso_ena = false;
1910		u32 tunnel = 0;
1911
1912		/* define outer network header type */
1913		if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1914			tunnel |= (first->tx_flags & ICE_TX_FLAGS_TSO) ?
1915				  ICE_TX_CTX_EIPT_IPV4 :
1916				  ICE_TX_CTX_EIPT_IPV4_NO_CSUM;
1917			l4_proto = ip.v4->protocol;
1918		} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
 
 
1919			tunnel |= ICE_TX_CTX_EIPT_IPV6;
1920			exthdr = ip.hdr + sizeof(*ip.v6);
1921			l4_proto = ip.v6->nexthdr;
1922			if (l4.hdr != exthdr)
1923				ipv6_skip_exthdr(skb, exthdr - skb->data,
1924						 &l4_proto, &frag_off);
 
1925		}
1926
1927		/* define outer transport */
1928		switch (l4_proto) {
1929		case IPPROTO_UDP:
1930			tunnel |= ICE_TXD_CTX_UDP_TUNNELING;
1931			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1932			break;
1933		case IPPROTO_GRE:
1934			tunnel |= ICE_TXD_CTX_GRE_TUNNELING;
1935			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1936			break;
1937		case IPPROTO_IPIP:
1938		case IPPROTO_IPV6:
1939			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1940			l4.hdr = skb_inner_network_header(skb);
1941			break;
1942		default:
1943			if (first->tx_flags & ICE_TX_FLAGS_TSO)
1944				return -1;
1945
1946			skb_checksum_help(skb);
1947			return 0;
1948		}
1949
1950		/* compute outer L3 header size */
1951		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
1952			  ICE_TXD_CTX_QW0_EIPLEN_S;
1953
1954		/* switch IP header pointer from outer to inner header */
1955		ip.hdr = skb_inner_network_header(skb);
1956
1957		/* compute tunnel header size */
1958		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
1959			   ICE_TXD_CTX_QW0_NATLEN_S;
1960
1961		gso_ena = skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL;
1962		/* indicate if we need to offload outer UDP header */
1963		if ((first->tx_flags & ICE_TX_FLAGS_TSO) && !gso_ena &&
1964		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
1965			tunnel |= ICE_TXD_CTX_QW0_L4T_CS_M;
1966
1967		/* record tunnel offload values */
1968		off->cd_tunnel_params |= tunnel;
1969
1970		/* set DTYP=1 to indicate that it's an Tx context descriptor
1971		 * in IPsec tunnel mode with Tx offloads in Quad word 1
1972		 */
1973		off->cd_qw1 |= (u64)ICE_TX_DESC_DTYPE_CTX;
1974
1975		/* switch L4 header pointer from outer to inner */
1976		l4.hdr = skb_inner_transport_header(skb);
1977		l4_proto = 0;
1978
1979		/* reset type as we transition from outer to inner headers */
1980		first->tx_flags &= ~(ICE_TX_FLAGS_IPV4 | ICE_TX_FLAGS_IPV6);
1981		if (ip.v4->version == 4)
1982			first->tx_flags |= ICE_TX_FLAGS_IPV4;
1983		if (ip.v6->version == 6)
1984			first->tx_flags |= ICE_TX_FLAGS_IPV6;
1985	}
1986
1987	/* Enable IP checksum offloads */
1988	if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1989		l4_proto = ip.v4->protocol;
1990		/* the stack computes the IP header already, the only time we
1991		 * need the hardware to recompute it is in the case of TSO.
1992		 */
1993		if (first->tx_flags & ICE_TX_FLAGS_TSO)
1994			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4_CSUM;
1995		else
1996			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4;
1997
1998	} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
1999		cmd |= ICE_TX_DESC_CMD_IIPT_IPV6;
2000		exthdr = ip.hdr + sizeof(*ip.v6);
2001		l4_proto = ip.v6->nexthdr;
2002		if (l4.hdr != exthdr)
2003			ipv6_skip_exthdr(skb, exthdr - skb->data, &l4_proto,
2004					 &frag_off);
2005	} else {
2006		return -1;
2007	}
2008
2009	/* compute inner L3 header size */
2010	l3_len = l4.hdr - ip.hdr;
2011	offset |= (l3_len / 4) << ICE_TX_DESC_LEN_IPLEN_S;
2012
2013	/* Enable L4 checksum offloads */
2014	switch (l4_proto) {
2015	case IPPROTO_TCP:
2016		/* enable checksum offloads */
2017		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_TCP;
2018		l4_len = l4.tcp->doff;
2019		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2020		break;
2021	case IPPROTO_UDP:
2022		/* enable UDP checksum offload */
2023		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_UDP;
2024		l4_len = (sizeof(struct udphdr) >> 2);
2025		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2026		break;
2027	case IPPROTO_SCTP:
2028		/* enable SCTP checksum offload */
2029		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_SCTP;
2030		l4_len = sizeof(struct sctphdr) >> 2;
2031		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
2032		break;
2033
2034	default:
2035		if (first->tx_flags & ICE_TX_FLAGS_TSO)
2036			return -1;
2037		skb_checksum_help(skb);
2038		return 0;
2039	}
2040
2041	off->td_cmd |= cmd;
2042	off->td_offset |= offset;
2043	return 1;
2044}
2045
2046/**
2047 * ice_tx_prepare_vlan_flags - prepare generic Tx VLAN tagging flags for HW
2048 * @tx_ring: ring to send buffer on
2049 * @first: pointer to struct ice_tx_buf
2050 *
2051 * Checks the skb and set up correspondingly several generic transmit flags
2052 * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
2053 */
2054static void
2055ice_tx_prepare_vlan_flags(struct ice_ring *tx_ring, struct ice_tx_buf *first)
2056{
2057	struct sk_buff *skb = first->skb;
2058
2059	/* nothing left to do, software offloaded VLAN */
2060	if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol))
2061		return;
2062
2063	/* currently, we always assume 802.1Q for VLAN insertion as VLAN
2064	 * insertion for 802.1AD is not supported
 
2065	 */
2066	if (skb_vlan_tag_present(skb)) {
2067		first->tx_flags |= skb_vlan_tag_get(skb) << ICE_TX_FLAGS_VLAN_S;
2068		first->tx_flags |= ICE_TX_FLAGS_HW_VLAN;
 
 
 
2069	}
2070
2071	ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
2072}
2073
2074/**
2075 * ice_tso - computes mss and TSO length to prepare for TSO
2076 * @first: pointer to struct ice_tx_buf
2077 * @off: pointer to struct that holds offload parameters
2078 *
2079 * Returns 0 or error (negative) if TSO can't happen, 1 otherwise.
2080 */
2081static
2082int ice_tso(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2083{
2084	struct sk_buff *skb = first->skb;
2085	union {
2086		struct iphdr *v4;
2087		struct ipv6hdr *v6;
2088		unsigned char *hdr;
2089	} ip;
2090	union {
2091		struct tcphdr *tcp;
2092		struct udphdr *udp;
2093		unsigned char *hdr;
2094	} l4;
2095	u64 cd_mss, cd_tso_len;
 
2096	u32 paylen;
2097	u8 l4_start;
2098	int err;
2099
2100	if (skb->ip_summed != CHECKSUM_PARTIAL)
2101		return 0;
2102
2103	if (!skb_is_gso(skb))
2104		return 0;
2105
2106	err = skb_cow_head(skb, 0);
2107	if (err < 0)
2108		return err;
2109
2110	/* cppcheck-suppress unreadVariable */
2111	ip.hdr = skb_network_header(skb);
2112	l4.hdr = skb_transport_header(skb);
 
 
 
 
 
2113
2114	/* initialize outer IP header fields */
2115	if (ip.v4->version == 4) {
2116		ip.v4->tot_len = 0;
2117		ip.v4->check = 0;
2118	} else {
2119		ip.v6->payload_len = 0;
2120	}
2121
2122	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2123					 SKB_GSO_GRE_CSUM |
2124					 SKB_GSO_IPXIP4 |
2125					 SKB_GSO_IPXIP6 |
2126					 SKB_GSO_UDP_TUNNEL |
2127					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2128		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2129		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2130			l4.udp->len = 0;
2131
2132			/* determine offset of outer transport header */
2133			l4_start = (u8)(l4.hdr - skb->data);
2134
2135			/* remove payload length from outer checksum */
2136			paylen = skb->len - l4_start;
2137			csum_replace_by_diff(&l4.udp->check,
2138					     (__force __wsum)htonl(paylen));
2139		}
2140
2141		/* reset pointers to inner headers */
2142
2143		/* cppcheck-suppress unreadVariable */
2144		ip.hdr = skb_inner_network_header(skb);
2145		l4.hdr = skb_inner_transport_header(skb);
2146
2147		/* initialize inner IP header fields */
2148		if (ip.v4->version == 4) {
2149			ip.v4->tot_len = 0;
2150			ip.v4->check = 0;
2151		} else {
2152			ip.v6->payload_len = 0;
2153		}
2154	}
2155
2156	/* determine offset of transport header */
2157	l4_start = (u8)(l4.hdr - skb->data);
2158
2159	/* remove payload length from checksum */
2160	paylen = skb->len - l4_start;
2161
2162	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
2163		csum_replace_by_diff(&l4.udp->check,
2164				     (__force __wsum)htonl(paylen));
2165		/* compute length of UDP segmentation header */
2166		off->header_len = (u8)sizeof(l4.udp) + l4_start;
2167	} else {
2168		csum_replace_by_diff(&l4.tcp->check,
2169				     (__force __wsum)htonl(paylen));
2170		/* compute length of TCP segmentation header */
2171		off->header_len = (u8)((l4.tcp->doff * 4) + l4_start);
2172	}
2173
2174	/* update gso_segs and bytecount */
2175	first->gso_segs = skb_shinfo(skb)->gso_segs;
2176	first->bytecount += (first->gso_segs - 1) * off->header_len;
2177
2178	cd_tso_len = skb->len - off->header_len;
2179	cd_mss = skb_shinfo(skb)->gso_size;
2180
2181	/* record cdesc_qw1 with TSO parameters */
2182	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2183			     (ICE_TX_CTX_DESC_TSO << ICE_TXD_CTX_QW1_CMD_S) |
2184			     (cd_tso_len << ICE_TXD_CTX_QW1_TSO_LEN_S) |
2185			     (cd_mss << ICE_TXD_CTX_QW1_MSS_S));
2186	first->tx_flags |= ICE_TX_FLAGS_TSO;
2187	return 1;
2188}
2189
2190/**
2191 * ice_txd_use_count  - estimate the number of descriptors needed for Tx
2192 * @size: transmit request size in bytes
2193 *
2194 * Due to hardware alignment restrictions (4K alignment), we need to
2195 * assume that we can have no more than 12K of data per descriptor, even
2196 * though each descriptor can take up to 16K - 1 bytes of aligned memory.
2197 * Thus, we need to divide by 12K. But division is slow! Instead,
2198 * we decompose the operation into shifts and one relatively cheap
2199 * multiply operation.
2200 *
2201 * To divide by 12K, we first divide by 4K, then divide by 3:
2202 *     To divide by 4K, shift right by 12 bits
2203 *     To divide by 3, multiply by 85, then divide by 256
2204 *     (Divide by 256 is done by shifting right by 8 bits)
2205 * Finally, we add one to round up. Because 256 isn't an exact multiple of
2206 * 3, we'll underestimate near each multiple of 12K. This is actually more
2207 * accurate as we have 4K - 1 of wiggle room that we can fit into the last
2208 * segment. For our purposes this is accurate out to 1M which is orders of
2209 * magnitude greater than our largest possible GSO size.
2210 *
2211 * This would then be implemented as:
2212 *     return (((size >> 12) * 85) >> 8) + ICE_DESCS_FOR_SKB_DATA_PTR;
2213 *
2214 * Since multiplication and division are commutative, we can reorder
2215 * operations into:
2216 *     return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2217 */
2218static unsigned int ice_txd_use_count(unsigned int size)
2219{
2220	return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2221}
2222
2223/**
2224 * ice_xmit_desc_count - calculate number of Tx descriptors needed
2225 * @skb: send buffer
2226 *
2227 * Returns number of data descriptors needed for this skb.
2228 */
2229static unsigned int ice_xmit_desc_count(struct sk_buff *skb)
2230{
2231	const skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
2232	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
2233	unsigned int count = 0, size = skb_headlen(skb);
2234
2235	for (;;) {
2236		count += ice_txd_use_count(size);
2237
2238		if (!nr_frags--)
2239			break;
2240
2241		size = skb_frag_size(frag++);
2242	}
2243
2244	return count;
2245}
2246
2247/**
2248 * __ice_chk_linearize - Check if there are more than 8 buffers per packet
2249 * @skb: send buffer
2250 *
2251 * Note: This HW can't DMA more than 8 buffers to build a packet on the wire
2252 * and so we need to figure out the cases where we need to linearize the skb.
2253 *
2254 * For TSO we need to count the TSO header and segment payload separately.
2255 * As such we need to check cases where we have 7 fragments or more as we
2256 * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2257 * the segment payload in the first descriptor, and another 7 for the
2258 * fragments.
2259 */
2260static bool __ice_chk_linearize(struct sk_buff *skb)
2261{
2262	const skb_frag_t *frag, *stale;
2263	int nr_frags, sum;
2264
2265	/* no need to check if number of frags is less than 7 */
2266	nr_frags = skb_shinfo(skb)->nr_frags;
2267	if (nr_frags < (ICE_MAX_BUF_TXD - 1))
2268		return false;
2269
2270	/* We need to walk through the list and validate that each group
2271	 * of 6 fragments totals at least gso_size.
2272	 */
2273	nr_frags -= ICE_MAX_BUF_TXD - 2;
2274	frag = &skb_shinfo(skb)->frags[0];
2275
2276	/* Initialize size to the negative value of gso_size minus 1. We
2277	 * use this as the worst case scenario in which the frag ahead
2278	 * of us only provides one byte which is why we are limited to 6
2279	 * descriptors for a single transmit as the header and previous
2280	 * fragment are already consuming 2 descriptors.
2281	 */
2282	sum = 1 - skb_shinfo(skb)->gso_size;
2283
2284	/* Add size of frags 0 through 4 to create our initial sum */
2285	sum += skb_frag_size(frag++);
2286	sum += skb_frag_size(frag++);
2287	sum += skb_frag_size(frag++);
2288	sum += skb_frag_size(frag++);
2289	sum += skb_frag_size(frag++);
2290
2291	/* Walk through fragments adding latest fragment, testing it, and
2292	 * then removing stale fragments from the sum.
2293	 */
2294	for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
2295		int stale_size = skb_frag_size(stale);
2296
2297		sum += skb_frag_size(frag++);
2298
2299		/* The stale fragment may present us with a smaller
2300		 * descriptor than the actual fragment size. To account
2301		 * for that we need to remove all the data on the front and
2302		 * figure out what the remainder would be in the last
2303		 * descriptor associated with the fragment.
2304		 */
2305		if (stale_size > ICE_MAX_DATA_PER_TXD) {
2306			int align_pad = -(skb_frag_off(stale)) &
2307					(ICE_MAX_READ_REQ_SIZE - 1);
2308
2309			sum -= align_pad;
2310			stale_size -= align_pad;
2311
2312			do {
2313				sum -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2314				stale_size -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2315			} while (stale_size > ICE_MAX_DATA_PER_TXD);
2316		}
2317
2318		/* if sum is negative we failed to make sufficient progress */
2319		if (sum < 0)
2320			return true;
2321
2322		if (!nr_frags--)
2323			break;
2324
2325		sum -= stale_size;
2326	}
2327
2328	return false;
2329}
2330
2331/**
2332 * ice_chk_linearize - Check if there are more than 8 fragments per packet
2333 * @skb:      send buffer
2334 * @count:    number of buffers used
2335 *
2336 * Note: Our HW can't scatter-gather more than 8 fragments to build
2337 * a packet on the wire and so we need to figure out the cases where we
2338 * need to linearize the skb.
2339 */
2340static bool ice_chk_linearize(struct sk_buff *skb, unsigned int count)
2341{
2342	/* Both TSO and single send will work if count is less than 8 */
2343	if (likely(count < ICE_MAX_BUF_TXD))
2344		return false;
2345
2346	if (skb_is_gso(skb))
2347		return __ice_chk_linearize(skb);
2348
2349	/* we can support up to 8 data buffers for a single send */
2350	return count != ICE_MAX_BUF_TXD;
2351}
2352
2353/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2354 * ice_xmit_frame_ring - Sends buffer on Tx ring
2355 * @skb: send buffer
2356 * @tx_ring: ring to send buffer on
2357 *
2358 * Returns NETDEV_TX_OK if sent, else an error code
2359 */
2360static netdev_tx_t
2361ice_xmit_frame_ring(struct sk_buff *skb, struct ice_ring *tx_ring)
2362{
2363	struct ice_tx_offload_params offload = { 0 };
2364	struct ice_vsi *vsi = tx_ring->vsi;
2365	struct ice_tx_buf *first;
 
2366	unsigned int count;
2367	int tso, csum;
2368
 
 
2369	count = ice_xmit_desc_count(skb);
2370	if (ice_chk_linearize(skb, count)) {
2371		if (__skb_linearize(skb))
2372			goto out_drop;
2373		count = ice_txd_use_count(skb->len);
2374		tx_ring->tx_stats.tx_linearize++;
2375	}
2376
2377	/* need: 1 descriptor per page * PAGE_SIZE/ICE_MAX_DATA_PER_TXD,
2378	 *       + 1 desc for skb_head_len/ICE_MAX_DATA_PER_TXD,
2379	 *       + 4 desc gap to avoid the cache line where head is,
2380	 *       + 1 desc for context descriptor,
2381	 * otherwise try next time
2382	 */
2383	if (ice_maybe_stop_tx(tx_ring, count + ICE_DESCS_PER_CACHE_LINE +
2384			      ICE_DESCS_FOR_CTX_DESC)) {
2385		tx_ring->tx_stats.tx_busy++;
2386		return NETDEV_TX_BUSY;
2387	}
2388
 
 
 
2389	offload.tx_ring = tx_ring;
2390
2391	/* record the location of the first descriptor for this packet */
2392	first = &tx_ring->tx_buf[tx_ring->next_to_use];
2393	first->skb = skb;
2394	first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
2395	first->gso_segs = 1;
2396	first->tx_flags = 0;
2397
2398	/* prepare the VLAN tagging flags for Tx */
2399	ice_tx_prepare_vlan_flags(tx_ring, first);
 
 
 
 
 
 
 
2400
2401	/* set up TSO offload */
2402	tso = ice_tso(first, &offload);
2403	if (tso < 0)
2404		goto out_drop;
2405
2406	/* always set up Tx checksum offload */
2407	csum = ice_tx_csum(first, &offload);
2408	if (csum < 0)
2409		goto out_drop;
2410
2411	/* allow CONTROL frames egress from main VSI if FW LLDP disabled */
2412	if (unlikely(skb->priority == TC_PRIO_CONTROL &&
 
 
2413		     vsi->type == ICE_VSI_PF &&
2414		     vsi->port_info->is_sw_lldp))
2415		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2416					ICE_TX_CTX_DESC_SWTCH_UPLINK <<
2417					ICE_TXD_CTX_QW1_CMD_S);
2418
 
 
 
 
2419	if (offload.cd_qw1 & ICE_TX_DESC_DTYPE_CTX) {
2420		struct ice_tx_ctx_desc *cdesc;
2421		u16 i = tx_ring->next_to_use;
2422
2423		/* grab the next descriptor */
2424		cdesc = ICE_TX_CTX_DESC(tx_ring, i);
2425		i++;
2426		tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2427
2428		/* setup context descriptor */
2429		cdesc->tunneling_params = cpu_to_le32(offload.cd_tunnel_params);
2430		cdesc->l2tag2 = cpu_to_le16(offload.cd_l2tag2);
2431		cdesc->rsvd = cpu_to_le16(0);
2432		cdesc->qw1 = cpu_to_le64(offload.cd_qw1);
2433	}
2434
2435	ice_tx_map(tx_ring, first, &offload);
2436	return NETDEV_TX_OK;
2437
2438out_drop:
 
2439	dev_kfree_skb_any(skb);
2440	return NETDEV_TX_OK;
2441}
2442
2443/**
2444 * ice_start_xmit - Selects the correct VSI and Tx queue to send buffer
2445 * @skb: send buffer
2446 * @netdev: network interface device structure
2447 *
2448 * Returns NETDEV_TX_OK if sent, else an error code
2449 */
2450netdev_tx_t ice_start_xmit(struct sk_buff *skb, struct net_device *netdev)
2451{
2452	struct ice_netdev_priv *np = netdev_priv(netdev);
2453	struct ice_vsi *vsi = np->vsi;
2454	struct ice_ring *tx_ring;
2455
2456	tx_ring = vsi->tx_rings[skb->queue_mapping];
2457
2458	/* hardware can't handle really short frames, hardware padding works
2459	 * beyond this point
2460	 */
2461	if (skb_put_padto(skb, ICE_MIN_TX_LEN))
2462		return NETDEV_TX_OK;
2463
2464	return ice_xmit_frame_ring(skb, tx_ring);
2465}
2466
2467/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2468 * ice_clean_ctrl_tx_irq - interrupt handler for flow director Tx queue
2469 * @tx_ring: tx_ring to clean
2470 */
2471void ice_clean_ctrl_tx_irq(struct ice_ring *tx_ring)
2472{
2473	struct ice_vsi *vsi = tx_ring->vsi;
2474	s16 i = tx_ring->next_to_clean;
2475	int budget = ICE_DFLT_IRQ_WORK;
2476	struct ice_tx_desc *tx_desc;
2477	struct ice_tx_buf *tx_buf;
2478
2479	tx_buf = &tx_ring->tx_buf[i];
2480	tx_desc = ICE_TX_DESC(tx_ring, i);
2481	i -= tx_ring->count;
2482
2483	do {
2484		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
2485
2486		/* if next_to_watch is not set then there is no pending work */
2487		if (!eop_desc)
2488			break;
2489
2490		/* prevent any other reads prior to eop_desc */
2491		smp_rmb();
2492
2493		/* if the descriptor isn't done, no work to do */
2494		if (!(eop_desc->cmd_type_offset_bsz &
2495		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
2496			break;
2497
2498		/* clear next_to_watch to prevent false hangs */
2499		tx_buf->next_to_watch = NULL;
2500		tx_desc->buf_addr = 0;
2501		tx_desc->cmd_type_offset_bsz = 0;
2502
2503		/* move past filter desc */
2504		tx_buf++;
2505		tx_desc++;
2506		i++;
2507		if (unlikely(!i)) {
2508			i -= tx_ring->count;
2509			tx_buf = tx_ring->tx_buf;
2510			tx_desc = ICE_TX_DESC(tx_ring, 0);
2511		}
2512
2513		/* unmap the data header */
2514		if (dma_unmap_len(tx_buf, len))
2515			dma_unmap_single(tx_ring->dev,
2516					 dma_unmap_addr(tx_buf, dma),
2517					 dma_unmap_len(tx_buf, len),
2518					 DMA_TO_DEVICE);
2519		if (tx_buf->tx_flags & ICE_TX_FLAGS_DUMMY_PKT)
2520			devm_kfree(tx_ring->dev, tx_buf->raw_buf);
2521
2522		/* clear next_to_watch to prevent false hangs */
2523		tx_buf->raw_buf = NULL;
2524		tx_buf->tx_flags = 0;
2525		tx_buf->next_to_watch = NULL;
2526		dma_unmap_len_set(tx_buf, len, 0);
2527		tx_desc->buf_addr = 0;
2528		tx_desc->cmd_type_offset_bsz = 0;
2529
2530		/* move past eop_desc for start of next FD desc */
2531		tx_buf++;
2532		tx_desc++;
2533		i++;
2534		if (unlikely(!i)) {
2535			i -= tx_ring->count;
2536			tx_buf = tx_ring->tx_buf;
2537			tx_desc = ICE_TX_DESC(tx_ring, 0);
2538		}
2539
2540		budget--;
2541	} while (likely(budget));
2542
2543	i += tx_ring->count;
2544	tx_ring->next_to_clean = i;
2545
2546	/* re-enable interrupt if needed */
2547	ice_irq_dynamic_ena(&vsi->back->hw, vsi, vsi->q_vectors[0]);
2548}
v6.2
   1// SPDX-License-Identifier: GPL-2.0
   2/* Copyright (c) 2018, Intel Corporation. */
   3
   4/* The driver transmit and receive code */
   5
 
   6#include <linux/mm.h>
   7#include <linux/netdevice.h>
   8#include <linux/prefetch.h>
   9#include <linux/bpf_trace.h>
  10#include <net/dsfield.h>
  11#include <net/mpls.h>
  12#include <net/xdp.h>
  13#include "ice_txrx_lib.h"
  14#include "ice_lib.h"
  15#include "ice.h"
  16#include "ice_trace.h"
  17#include "ice_dcb_lib.h"
  18#include "ice_xsk.h"
  19#include "ice_eswitch.h"
  20
  21#define ICE_RX_HDR_SIZE		256
  22
  23#define FDIR_DESC_RXDID 0x40
  24#define ICE_FDIR_CLEAN_DELAY 10
  25
  26/**
  27 * ice_prgm_fdir_fltr - Program a Flow Director filter
  28 * @vsi: VSI to send dummy packet
  29 * @fdir_desc: flow director descriptor
  30 * @raw_packet: allocated buffer for flow director
  31 */
  32int
  33ice_prgm_fdir_fltr(struct ice_vsi *vsi, struct ice_fltr_desc *fdir_desc,
  34		   u8 *raw_packet)
  35{
  36	struct ice_tx_buf *tx_buf, *first;
  37	struct ice_fltr_desc *f_desc;
  38	struct ice_tx_desc *tx_desc;
  39	struct ice_tx_ring *tx_ring;
  40	struct device *dev;
  41	dma_addr_t dma;
  42	u32 td_cmd;
  43	u16 i;
  44
  45	/* VSI and Tx ring */
  46	if (!vsi)
  47		return -ENOENT;
  48	tx_ring = vsi->tx_rings[0];
  49	if (!tx_ring || !tx_ring->desc)
  50		return -ENOENT;
  51	dev = tx_ring->dev;
  52
  53	/* we are using two descriptors to add/del a filter and we can wait */
  54	for (i = ICE_FDIR_CLEAN_DELAY; ICE_DESC_UNUSED(tx_ring) < 2; i--) {
  55		if (!i)
  56			return -EAGAIN;
  57		msleep_interruptible(1);
  58	}
  59
  60	dma = dma_map_single(dev, raw_packet, ICE_FDIR_MAX_RAW_PKT_SIZE,
  61			     DMA_TO_DEVICE);
  62
  63	if (dma_mapping_error(dev, dma))
  64		return -EINVAL;
  65
  66	/* grab the next descriptor */
  67	i = tx_ring->next_to_use;
  68	first = &tx_ring->tx_buf[i];
  69	f_desc = ICE_TX_FDIRDESC(tx_ring, i);
  70	memcpy(f_desc, fdir_desc, sizeof(*f_desc));
  71
  72	i++;
  73	i = (i < tx_ring->count) ? i : 0;
  74	tx_desc = ICE_TX_DESC(tx_ring, i);
  75	tx_buf = &tx_ring->tx_buf[i];
  76
  77	i++;
  78	tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
  79
  80	memset(tx_buf, 0, sizeof(*tx_buf));
  81	dma_unmap_len_set(tx_buf, len, ICE_FDIR_MAX_RAW_PKT_SIZE);
  82	dma_unmap_addr_set(tx_buf, dma, dma);
  83
  84	tx_desc->buf_addr = cpu_to_le64(dma);
  85	td_cmd = ICE_TXD_LAST_DESC_CMD | ICE_TX_DESC_CMD_DUMMY |
  86		 ICE_TX_DESC_CMD_RE;
  87
  88	tx_buf->tx_flags = ICE_TX_FLAGS_DUMMY_PKT;
  89	tx_buf->raw_buf = raw_packet;
  90
  91	tx_desc->cmd_type_offset_bsz =
  92		ice_build_ctob(td_cmd, 0, ICE_FDIR_MAX_RAW_PKT_SIZE, 0);
  93
  94	/* Force memory write to complete before letting h/w know
  95	 * there are new descriptors to fetch.
  96	 */
  97	wmb();
  98
  99	/* mark the data descriptor to be watched */
 100	first->next_to_watch = tx_desc;
 101
 102	writel(tx_ring->next_to_use, tx_ring->tail);
 103
 104	return 0;
 105}
 106
 107/**
 108 * ice_unmap_and_free_tx_buf - Release a Tx buffer
 109 * @ring: the ring that owns the buffer
 110 * @tx_buf: the buffer to free
 111 */
 112static void
 113ice_unmap_and_free_tx_buf(struct ice_tx_ring *ring, struct ice_tx_buf *tx_buf)
 114{
 115	if (tx_buf->skb) {
 116		if (tx_buf->tx_flags & ICE_TX_FLAGS_DUMMY_PKT)
 117			devm_kfree(ring->dev, tx_buf->raw_buf);
 118		else if (ice_ring_is_xdp(ring))
 119			page_frag_free(tx_buf->raw_buf);
 120		else
 121			dev_kfree_skb_any(tx_buf->skb);
 122		if (dma_unmap_len(tx_buf, len))
 123			dma_unmap_single(ring->dev,
 124					 dma_unmap_addr(tx_buf, dma),
 125					 dma_unmap_len(tx_buf, len),
 126					 DMA_TO_DEVICE);
 127	} else if (dma_unmap_len(tx_buf, len)) {
 128		dma_unmap_page(ring->dev,
 129			       dma_unmap_addr(tx_buf, dma),
 130			       dma_unmap_len(tx_buf, len),
 131			       DMA_TO_DEVICE);
 132	}
 133
 134	tx_buf->next_to_watch = NULL;
 135	tx_buf->skb = NULL;
 136	dma_unmap_len_set(tx_buf, len, 0);
 137	/* tx_buf must be completely set up in the transmit path */
 138}
 139
 140static struct netdev_queue *txring_txq(const struct ice_tx_ring *ring)
 141{
 142	return netdev_get_tx_queue(ring->netdev, ring->q_index);
 143}
 144
 145/**
 146 * ice_clean_tx_ring - Free any empty Tx buffers
 147 * @tx_ring: ring to be cleaned
 148 */
 149void ice_clean_tx_ring(struct ice_tx_ring *tx_ring)
 150{
 151	u32 size;
 152	u16 i;
 153
 154	if (ice_ring_is_xdp(tx_ring) && tx_ring->xsk_pool) {
 155		ice_xsk_clean_xdp_ring(tx_ring);
 156		goto tx_skip_free;
 157	}
 158
 159	/* ring already cleared, nothing to do */
 160	if (!tx_ring->tx_buf)
 161		return;
 162
 163	/* Free all the Tx ring sk_buffs */
 164	for (i = 0; i < tx_ring->count; i++)
 165		ice_unmap_and_free_tx_buf(tx_ring, &tx_ring->tx_buf[i]);
 166
 167tx_skip_free:
 168	memset(tx_ring->tx_buf, 0, sizeof(*tx_ring->tx_buf) * tx_ring->count);
 169
 170	size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
 171		     PAGE_SIZE);
 172	/* Zero out the descriptor ring */
 173	memset(tx_ring->desc, 0, size);
 174
 175	tx_ring->next_to_use = 0;
 176	tx_ring->next_to_clean = 0;
 177	tx_ring->next_dd = ICE_RING_QUARTER(tx_ring) - 1;
 178	tx_ring->next_rs = ICE_RING_QUARTER(tx_ring) - 1;
 179
 180	if (!tx_ring->netdev)
 181		return;
 182
 183	/* cleanup Tx queue statistics */
 184	netdev_tx_reset_queue(txring_txq(tx_ring));
 185}
 186
 187/**
 188 * ice_free_tx_ring - Free Tx resources per queue
 189 * @tx_ring: Tx descriptor ring for a specific queue
 190 *
 191 * Free all transmit software resources
 192 */
 193void ice_free_tx_ring(struct ice_tx_ring *tx_ring)
 194{
 195	u32 size;
 196
 197	ice_clean_tx_ring(tx_ring);
 198	devm_kfree(tx_ring->dev, tx_ring->tx_buf);
 199	tx_ring->tx_buf = NULL;
 200
 201	if (tx_ring->desc) {
 202		size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
 203			     PAGE_SIZE);
 204		dmam_free_coherent(tx_ring->dev, size,
 205				   tx_ring->desc, tx_ring->dma);
 206		tx_ring->desc = NULL;
 207	}
 208}
 209
 210/**
 211 * ice_clean_tx_irq - Reclaim resources after transmit completes
 212 * @tx_ring: Tx ring to clean
 213 * @napi_budget: Used to determine if we are in netpoll
 214 *
 215 * Returns true if there's any budget left (e.g. the clean is finished)
 216 */
 217static bool ice_clean_tx_irq(struct ice_tx_ring *tx_ring, int napi_budget)
 218{
 219	unsigned int total_bytes = 0, total_pkts = 0;
 220	unsigned int budget = ICE_DFLT_IRQ_WORK;
 221	struct ice_vsi *vsi = tx_ring->vsi;
 222	s16 i = tx_ring->next_to_clean;
 223	struct ice_tx_desc *tx_desc;
 224	struct ice_tx_buf *tx_buf;
 225
 226	/* get the bql data ready */
 227	netdev_txq_bql_complete_prefetchw(txring_txq(tx_ring));
 228
 229	tx_buf = &tx_ring->tx_buf[i];
 230	tx_desc = ICE_TX_DESC(tx_ring, i);
 231	i -= tx_ring->count;
 232
 233	prefetch(&vsi->state);
 234
 235	do {
 236		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
 237
 238		/* if next_to_watch is not set then there is no work pending */
 239		if (!eop_desc)
 240			break;
 241
 242		/* follow the guidelines of other drivers */
 243		prefetchw(&tx_buf->skb->users);
 244
 245		smp_rmb();	/* prevent any other reads prior to eop_desc */
 246
 247		ice_trace(clean_tx_irq, tx_ring, tx_desc, tx_buf);
 248		/* if the descriptor isn't done, no work yet to do */
 249		if (!(eop_desc->cmd_type_offset_bsz &
 250		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
 251			break;
 252
 253		/* clear next_to_watch to prevent false hangs */
 254		tx_buf->next_to_watch = NULL;
 255
 256		/* update the statistics for this packet */
 257		total_bytes += tx_buf->bytecount;
 258		total_pkts += tx_buf->gso_segs;
 259
 260		/* free the skb */
 261		napi_consume_skb(tx_buf->skb, napi_budget);
 
 
 
 262
 263		/* unmap skb header data */
 264		dma_unmap_single(tx_ring->dev,
 265				 dma_unmap_addr(tx_buf, dma),
 266				 dma_unmap_len(tx_buf, len),
 267				 DMA_TO_DEVICE);
 268
 269		/* clear tx_buf data */
 270		tx_buf->skb = NULL;
 271		dma_unmap_len_set(tx_buf, len, 0);
 272
 273		/* unmap remaining buffers */
 274		while (tx_desc != eop_desc) {
 275			ice_trace(clean_tx_irq_unmap, tx_ring, tx_desc, tx_buf);
 276			tx_buf++;
 277			tx_desc++;
 278			i++;
 279			if (unlikely(!i)) {
 280				i -= tx_ring->count;
 281				tx_buf = tx_ring->tx_buf;
 282				tx_desc = ICE_TX_DESC(tx_ring, 0);
 283			}
 284
 285			/* unmap any remaining paged data */
 286			if (dma_unmap_len(tx_buf, len)) {
 287				dma_unmap_page(tx_ring->dev,
 288					       dma_unmap_addr(tx_buf, dma),
 289					       dma_unmap_len(tx_buf, len),
 290					       DMA_TO_DEVICE);
 291				dma_unmap_len_set(tx_buf, len, 0);
 292			}
 293		}
 294		ice_trace(clean_tx_irq_unmap_eop, tx_ring, tx_desc, tx_buf);
 295
 296		/* move us one more past the eop_desc for start of next pkt */
 297		tx_buf++;
 298		tx_desc++;
 299		i++;
 300		if (unlikely(!i)) {
 301			i -= tx_ring->count;
 302			tx_buf = tx_ring->tx_buf;
 303			tx_desc = ICE_TX_DESC(tx_ring, 0);
 304		}
 305
 306		prefetch(tx_desc);
 307
 308		/* update budget accounting */
 309		budget--;
 310	} while (likely(budget));
 311
 312	i += tx_ring->count;
 313	tx_ring->next_to_clean = i;
 314
 315	ice_update_tx_ring_stats(tx_ring, total_pkts, total_bytes);
 316	netdev_tx_completed_queue(txring_txq(tx_ring), total_pkts, total_bytes);
 
 
 
 
 
 317
 318#define TX_WAKE_THRESHOLD ((s16)(DESC_NEEDED * 2))
 319	if (unlikely(total_pkts && netif_carrier_ok(tx_ring->netdev) &&
 320		     (ICE_DESC_UNUSED(tx_ring) >= TX_WAKE_THRESHOLD))) {
 321		/* Make sure that anybody stopping the queue after this
 322		 * sees the new next_to_clean.
 323		 */
 324		smp_mb();
 325		if (netif_tx_queue_stopped(txring_txq(tx_ring)) &&
 326		    !test_bit(ICE_VSI_DOWN, vsi->state)) {
 327			netif_tx_wake_queue(txring_txq(tx_ring));
 328			++tx_ring->ring_stats->tx_stats.restart_q;
 
 
 329		}
 330	}
 331
 332	return !!budget;
 333}
 334
 335/**
 336 * ice_setup_tx_ring - Allocate the Tx descriptors
 337 * @tx_ring: the Tx ring to set up
 338 *
 339 * Return 0 on success, negative on error
 340 */
 341int ice_setup_tx_ring(struct ice_tx_ring *tx_ring)
 342{
 343	struct device *dev = tx_ring->dev;
 344	u32 size;
 345
 346	if (!dev)
 347		return -ENOMEM;
 348
 349	/* warn if we are about to overwrite the pointer */
 350	WARN_ON(tx_ring->tx_buf);
 351	tx_ring->tx_buf =
 352		devm_kcalloc(dev, sizeof(*tx_ring->tx_buf), tx_ring->count,
 353			     GFP_KERNEL);
 354	if (!tx_ring->tx_buf)
 355		return -ENOMEM;
 356
 357	/* round up to nearest page */
 358	size = ALIGN(tx_ring->count * sizeof(struct ice_tx_desc),
 359		     PAGE_SIZE);
 360	tx_ring->desc = dmam_alloc_coherent(dev, size, &tx_ring->dma,
 361					    GFP_KERNEL);
 362	if (!tx_ring->desc) {
 363		dev_err(dev, "Unable to allocate memory for the Tx descriptor ring, size=%d\n",
 364			size);
 365		goto err;
 366	}
 367
 368	tx_ring->next_to_use = 0;
 369	tx_ring->next_to_clean = 0;
 370	tx_ring->ring_stats->tx_stats.prev_pkt = -1;
 371	return 0;
 372
 373err:
 374	devm_kfree(dev, tx_ring->tx_buf);
 375	tx_ring->tx_buf = NULL;
 376	return -ENOMEM;
 377}
 378
 379/**
 380 * ice_clean_rx_ring - Free Rx buffers
 381 * @rx_ring: ring to be cleaned
 382 */
 383void ice_clean_rx_ring(struct ice_rx_ring *rx_ring)
 384{
 385	struct device *dev = rx_ring->dev;
 386	u32 size;
 387	u16 i;
 388
 389	/* ring already cleared, nothing to do */
 390	if (!rx_ring->rx_buf)
 391		return;
 392
 393	if (rx_ring->skb) {
 394		dev_kfree_skb(rx_ring->skb);
 395		rx_ring->skb = NULL;
 396	}
 397
 398	if (rx_ring->xsk_pool) {
 399		ice_xsk_clean_rx_ring(rx_ring);
 400		goto rx_skip_free;
 401	}
 402
 403	/* Free all the Rx ring sk_buffs */
 404	for (i = 0; i < rx_ring->count; i++) {
 405		struct ice_rx_buf *rx_buf = &rx_ring->rx_buf[i];
 406
 
 
 
 
 407		if (!rx_buf->page)
 408			continue;
 409
 410		/* Invalidate cache lines that may have been written to by
 411		 * device so that we avoid corrupting memory.
 412		 */
 413		dma_sync_single_range_for_cpu(dev, rx_buf->dma,
 414					      rx_buf->page_offset,
 415					      rx_ring->rx_buf_len,
 416					      DMA_FROM_DEVICE);
 417
 418		/* free resources associated with mapping */
 419		dma_unmap_page_attrs(dev, rx_buf->dma, ice_rx_pg_size(rx_ring),
 420				     DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
 421		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
 422
 423		rx_buf->page = NULL;
 424		rx_buf->page_offset = 0;
 425	}
 426
 427rx_skip_free:
 428	if (rx_ring->xsk_pool)
 429		memset(rx_ring->xdp_buf, 0, array_size(rx_ring->count, sizeof(*rx_ring->xdp_buf)));
 430	else
 431		memset(rx_ring->rx_buf, 0, array_size(rx_ring->count, sizeof(*rx_ring->rx_buf)));
 432
 433	/* Zero out the descriptor ring */
 434	size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
 435		     PAGE_SIZE);
 436	memset(rx_ring->desc, 0, size);
 437
 438	rx_ring->next_to_alloc = 0;
 439	rx_ring->next_to_clean = 0;
 440	rx_ring->next_to_use = 0;
 441}
 442
 443/**
 444 * ice_free_rx_ring - Free Rx resources
 445 * @rx_ring: ring to clean the resources from
 446 *
 447 * Free all receive software resources
 448 */
 449void ice_free_rx_ring(struct ice_rx_ring *rx_ring)
 450{
 451	u32 size;
 452
 453	ice_clean_rx_ring(rx_ring);
 454	if (rx_ring->vsi->type == ICE_VSI_PF)
 455		if (xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
 456			xdp_rxq_info_unreg(&rx_ring->xdp_rxq);
 457	rx_ring->xdp_prog = NULL;
 458	if (rx_ring->xsk_pool) {
 459		kfree(rx_ring->xdp_buf);
 460		rx_ring->xdp_buf = NULL;
 461	} else {
 462		kfree(rx_ring->rx_buf);
 463		rx_ring->rx_buf = NULL;
 464	}
 465
 466	if (rx_ring->desc) {
 467		size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
 468			     PAGE_SIZE);
 469		dmam_free_coherent(rx_ring->dev, size,
 470				   rx_ring->desc, rx_ring->dma);
 471		rx_ring->desc = NULL;
 472	}
 473}
 474
 475/**
 476 * ice_setup_rx_ring - Allocate the Rx descriptors
 477 * @rx_ring: the Rx ring to set up
 478 *
 479 * Return 0 on success, negative on error
 480 */
 481int ice_setup_rx_ring(struct ice_rx_ring *rx_ring)
 482{
 483	struct device *dev = rx_ring->dev;
 484	u32 size;
 485
 486	if (!dev)
 487		return -ENOMEM;
 488
 489	/* warn if we are about to overwrite the pointer */
 490	WARN_ON(rx_ring->rx_buf);
 491	rx_ring->rx_buf =
 492		kcalloc(rx_ring->count, sizeof(*rx_ring->rx_buf), GFP_KERNEL);
 
 493	if (!rx_ring->rx_buf)
 494		return -ENOMEM;
 495
 496	/* round up to nearest page */
 497	size = ALIGN(rx_ring->count * sizeof(union ice_32byte_rx_desc),
 498		     PAGE_SIZE);
 499	rx_ring->desc = dmam_alloc_coherent(dev, size, &rx_ring->dma,
 500					    GFP_KERNEL);
 501	if (!rx_ring->desc) {
 502		dev_err(dev, "Unable to allocate memory for the Rx descriptor ring, size=%d\n",
 503			size);
 504		goto err;
 505	}
 506
 507	rx_ring->next_to_use = 0;
 508	rx_ring->next_to_clean = 0;
 509
 510	if (ice_is_xdp_ena_vsi(rx_ring->vsi))
 511		WRITE_ONCE(rx_ring->xdp_prog, rx_ring->vsi->xdp_prog);
 512
 513	if (rx_ring->vsi->type == ICE_VSI_PF &&
 514	    !xdp_rxq_info_is_reg(&rx_ring->xdp_rxq))
 515		if (xdp_rxq_info_reg(&rx_ring->xdp_rxq, rx_ring->netdev,
 516				     rx_ring->q_index, rx_ring->q_vector->napi.napi_id))
 517			goto err;
 518	return 0;
 519
 520err:
 521	kfree(rx_ring->rx_buf);
 522	rx_ring->rx_buf = NULL;
 523	return -ENOMEM;
 524}
 525
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 526static unsigned int
 527ice_rx_frame_truesize(struct ice_rx_ring *rx_ring, unsigned int __maybe_unused size)
 528{
 529	unsigned int truesize;
 530
 531#if (PAGE_SIZE < 8192)
 532	truesize = ice_rx_pg_size(rx_ring) / 2; /* Must be power-of-2 */
 533#else
 534	truesize = rx_ring->rx_offset ?
 535		SKB_DATA_ALIGN(rx_ring->rx_offset + size) +
 536		SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) :
 537		SKB_DATA_ALIGN(size);
 538#endif
 539	return truesize;
 540}
 541
 542/**
 543 * ice_run_xdp - Executes an XDP program on initialized xdp_buff
 544 * @rx_ring: Rx ring
 545 * @xdp: xdp_buff used as input to the XDP program
 546 * @xdp_prog: XDP program to run
 547 * @xdp_ring: ring to be used for XDP_TX action
 548 *
 549 * Returns any of ICE_XDP_{PASS, CONSUMED, TX, REDIR}
 550 */
 551static int
 552ice_run_xdp(struct ice_rx_ring *rx_ring, struct xdp_buff *xdp,
 553	    struct bpf_prog *xdp_prog, struct ice_tx_ring *xdp_ring)
 554{
 555	int err;
 
 556	u32 act;
 557
 558	act = bpf_prog_run_xdp(xdp_prog, xdp);
 559	switch (act) {
 560	case XDP_PASS:
 561		return ICE_XDP_PASS;
 562	case XDP_TX:
 563		if (static_branch_unlikely(&ice_xdp_locking_key))
 564			spin_lock(&xdp_ring->tx_lock);
 565		err = ice_xmit_xdp_ring(xdp->data, xdp->data_end - xdp->data, xdp_ring);
 566		if (static_branch_unlikely(&ice_xdp_locking_key))
 567			spin_unlock(&xdp_ring->tx_lock);
 568		if (err == ICE_XDP_CONSUMED)
 569			goto out_failure;
 570		return err;
 571	case XDP_REDIRECT:
 572		err = xdp_do_redirect(rx_ring->netdev, xdp, xdp_prog);
 573		if (err)
 574			goto out_failure;
 575		return ICE_XDP_REDIR;
 576	default:
 577		bpf_warn_invalid_xdp_action(rx_ring->netdev, xdp_prog, act);
 578		fallthrough;
 579	case XDP_ABORTED:
 580out_failure:
 581		trace_xdp_exception(rx_ring->netdev, xdp_prog, act);
 582		fallthrough;
 583	case XDP_DROP:
 584		return ICE_XDP_CONSUMED;
 
 585	}
 
 
 586}
 587
 588/**
 589 * ice_xdp_xmit - submit packets to XDP ring for transmission
 590 * @dev: netdev
 591 * @n: number of XDP frames to be transmitted
 592 * @frames: XDP frames to be transmitted
 593 * @flags: transmit flags
 594 *
 595 * Returns number of frames successfully sent. Failed frames
 596 * will be free'ed by XDP core.
 597 * For error cases, a negative errno code is returned and no-frames
 598 * are transmitted (caller must handle freeing frames).
 599 */
 600int
 601ice_xdp_xmit(struct net_device *dev, int n, struct xdp_frame **frames,
 602	     u32 flags)
 603{
 604	struct ice_netdev_priv *np = netdev_priv(dev);
 605	unsigned int queue_index = smp_processor_id();
 606	struct ice_vsi *vsi = np->vsi;
 607	struct ice_tx_ring *xdp_ring;
 608	int nxmit = 0, i;
 609
 610	if (test_bit(ICE_VSI_DOWN, vsi->state))
 611		return -ENETDOWN;
 612
 613	if (!ice_is_xdp_ena_vsi(vsi))
 614		return -ENXIO;
 615
 616	if (unlikely(flags & ~XDP_XMIT_FLAGS_MASK))
 617		return -EINVAL;
 618
 619	if (static_branch_unlikely(&ice_xdp_locking_key)) {
 620		queue_index %= vsi->num_xdp_txq;
 621		xdp_ring = vsi->xdp_rings[queue_index];
 622		spin_lock(&xdp_ring->tx_lock);
 623	} else {
 624		/* Generally, should not happen */
 625		if (unlikely(queue_index >= vsi->num_xdp_txq))
 626			return -ENXIO;
 627		xdp_ring = vsi->xdp_rings[queue_index];
 628	}
 629
 630	for (i = 0; i < n; i++) {
 631		struct xdp_frame *xdpf = frames[i];
 632		int err;
 633
 634		err = ice_xmit_xdp_ring(xdpf->data, xdpf->len, xdp_ring);
 635		if (err != ICE_XDP_TX)
 636			break;
 637		nxmit++;
 
 638	}
 639
 640	if (unlikely(flags & XDP_XMIT_FLUSH))
 641		ice_xdp_ring_update_tail(xdp_ring);
 642
 643	if (static_branch_unlikely(&ice_xdp_locking_key))
 644		spin_unlock(&xdp_ring->tx_lock);
 645
 646	return nxmit;
 647}
 648
 649/**
 650 * ice_alloc_mapped_page - recycle or make a new page
 651 * @rx_ring: ring to use
 652 * @bi: rx_buf struct to modify
 653 *
 654 * Returns true if the page was successfully allocated or
 655 * reused.
 656 */
 657static bool
 658ice_alloc_mapped_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *bi)
 659{
 660	struct page *page = bi->page;
 661	dma_addr_t dma;
 662
 663	/* since we are recycling buffers we should seldom need to alloc */
 664	if (likely(page))
 665		return true;
 666
 667	/* alloc new page for storage */
 668	page = dev_alloc_pages(ice_rx_pg_order(rx_ring));
 669	if (unlikely(!page)) {
 670		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
 671		return false;
 672	}
 673
 674	/* map page for use */
 675	dma = dma_map_page_attrs(rx_ring->dev, page, 0, ice_rx_pg_size(rx_ring),
 676				 DMA_FROM_DEVICE, ICE_RX_DMA_ATTR);
 677
 678	/* if mapping failed free memory back to system since
 679	 * there isn't much point in holding memory we can't use
 680	 */
 681	if (dma_mapping_error(rx_ring->dev, dma)) {
 682		__free_pages(page, ice_rx_pg_order(rx_ring));
 683		rx_ring->ring_stats->rx_stats.alloc_page_failed++;
 684		return false;
 685	}
 686
 687	bi->dma = dma;
 688	bi->page = page;
 689	bi->page_offset = rx_ring->rx_offset;
 690	page_ref_add(page, USHRT_MAX - 1);
 691	bi->pagecnt_bias = USHRT_MAX;
 692
 693	return true;
 694}
 695
 696/**
 697 * ice_alloc_rx_bufs - Replace used receive buffers
 698 * @rx_ring: ring to place buffers on
 699 * @cleaned_count: number of buffers to replace
 700 *
 701 * Returns false if all allocations were successful, true if any fail. Returning
 702 * true signals to the caller that we didn't replace cleaned_count buffers and
 703 * there is more work to do.
 704 *
 705 * First, try to clean "cleaned_count" Rx buffers. Then refill the cleaned Rx
 706 * buffers. Then bump tail at most one time. Grouping like this lets us avoid
 707 * multiple tail writes per call.
 708 */
 709bool ice_alloc_rx_bufs(struct ice_rx_ring *rx_ring, u16 cleaned_count)
 710{
 711	union ice_32b_rx_flex_desc *rx_desc;
 712	u16 ntu = rx_ring->next_to_use;
 713	struct ice_rx_buf *bi;
 714
 715	/* do nothing if no valid netdev defined */
 716	if ((!rx_ring->netdev && rx_ring->vsi->type != ICE_VSI_CTRL) ||
 717	    !cleaned_count)
 718		return false;
 719
 720	/* get the Rx descriptor and buffer based on next_to_use */
 721	rx_desc = ICE_RX_DESC(rx_ring, ntu);
 722	bi = &rx_ring->rx_buf[ntu];
 723
 724	do {
 725		/* if we fail here, we have work remaining */
 726		if (!ice_alloc_mapped_page(rx_ring, bi))
 727			break;
 728
 729		/* sync the buffer for use by the device */
 730		dma_sync_single_range_for_device(rx_ring->dev, bi->dma,
 731						 bi->page_offset,
 732						 rx_ring->rx_buf_len,
 733						 DMA_FROM_DEVICE);
 734
 735		/* Refresh the desc even if buffer_addrs didn't change
 736		 * because each write-back erases this info.
 737		 */
 738		rx_desc->read.pkt_addr = cpu_to_le64(bi->dma + bi->page_offset);
 739
 740		rx_desc++;
 741		bi++;
 742		ntu++;
 743		if (unlikely(ntu == rx_ring->count)) {
 744			rx_desc = ICE_RX_DESC(rx_ring, 0);
 745			bi = rx_ring->rx_buf;
 746			ntu = 0;
 747		}
 748
 749		/* clear the status bits for the next_to_use descriptor */
 750		rx_desc->wb.status_error0 = 0;
 751
 752		cleaned_count--;
 753	} while (cleaned_count);
 754
 755	if (rx_ring->next_to_use != ntu)
 756		ice_release_rx_desc(rx_ring, ntu);
 757
 758	return !!cleaned_count;
 759}
 760
 761/**
 
 
 
 
 
 
 
 
 
 762 * ice_rx_buf_adjust_pg_offset - Prepare Rx buffer for reuse
 763 * @rx_buf: Rx buffer to adjust
 764 * @size: Size of adjustment
 765 *
 766 * Update the offset within page so that Rx buf will be ready to be reused.
 767 * For systems with PAGE_SIZE < 8192 this function will flip the page offset
 768 * so the second half of page assigned to Rx buffer will be used, otherwise
 769 * the offset is moved by "size" bytes
 770 */
 771static void
 772ice_rx_buf_adjust_pg_offset(struct ice_rx_buf *rx_buf, unsigned int size)
 773{
 774#if (PAGE_SIZE < 8192)
 775	/* flip page offset to other buffer */
 776	rx_buf->page_offset ^= size;
 777#else
 778	/* move offset up to the next cache line */
 779	rx_buf->page_offset += size;
 780#endif
 781}
 782
 783/**
 784 * ice_can_reuse_rx_page - Determine if page can be reused for another Rx
 785 * @rx_buf: buffer containing the page
 786 * @rx_buf_pgcnt: rx_buf page refcount pre xdp_do_redirect() call
 787 *
 788 * If page is reusable, we have a green light for calling ice_reuse_rx_page,
 789 * which will assign the current buffer to the buffer that next_to_alloc is
 790 * pointing to; otherwise, the DMA mapping needs to be destroyed and
 791 * page freed
 792 */
 793static bool
 794ice_can_reuse_rx_page(struct ice_rx_buf *rx_buf, int rx_buf_pgcnt)
 795{
 796	unsigned int pagecnt_bias = rx_buf->pagecnt_bias;
 797	struct page *page = rx_buf->page;
 798
 799	/* avoid re-using remote and pfmemalloc pages */
 800	if (!dev_page_is_reusable(page))
 801		return false;
 802
 803#if (PAGE_SIZE < 8192)
 804	/* if we are only owner of page we can reuse it */
 805	if (unlikely((rx_buf_pgcnt - pagecnt_bias) > 1))
 806		return false;
 807#else
 808#define ICE_LAST_OFFSET \
 809	(SKB_WITH_OVERHEAD(PAGE_SIZE) - ICE_RXBUF_2048)
 810	if (rx_buf->page_offset > ICE_LAST_OFFSET)
 811		return false;
 812#endif /* PAGE_SIZE < 8192) */
 813
 814	/* If we have drained the page fragment pool we need to update
 815	 * the pagecnt_bias and page count so that we fully restock the
 816	 * number of references the driver holds.
 817	 */
 818	if (unlikely(pagecnt_bias == 1)) {
 819		page_ref_add(page, USHRT_MAX - 1);
 820		rx_buf->pagecnt_bias = USHRT_MAX;
 821	}
 822
 823	return true;
 824}
 825
 826/**
 827 * ice_add_rx_frag - Add contents of Rx buffer to sk_buff as a frag
 828 * @rx_ring: Rx descriptor ring to transact packets on
 829 * @rx_buf: buffer containing page to add
 830 * @skb: sk_buff to place the data into
 831 * @size: packet length from rx_desc
 832 *
 833 * This function will add the data contained in rx_buf->page to the skb.
 834 * It will just attach the page as a frag to the skb.
 835 * The function will then update the page offset.
 836 */
 837static void
 838ice_add_rx_frag(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf,
 839		struct sk_buff *skb, unsigned int size)
 840{
 841#if (PAGE_SIZE >= 8192)
 842	unsigned int truesize = SKB_DATA_ALIGN(size + rx_ring->rx_offset);
 843#else
 844	unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
 845#endif
 846
 847	if (!size)
 848		return;
 849	skb_add_rx_frag(skb, skb_shinfo(skb)->nr_frags, rx_buf->page,
 850			rx_buf->page_offset, size, truesize);
 851
 852	/* page is being used so we must update the page offset */
 853	ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
 854}
 855
 856/**
 857 * ice_reuse_rx_page - page flip buffer and store it back on the ring
 858 * @rx_ring: Rx descriptor ring to store buffers on
 859 * @old_buf: donor buffer to have page reused
 860 *
 861 * Synchronizes page for reuse by the adapter
 862 */
 863static void
 864ice_reuse_rx_page(struct ice_rx_ring *rx_ring, struct ice_rx_buf *old_buf)
 865{
 866	u16 nta = rx_ring->next_to_alloc;
 867	struct ice_rx_buf *new_buf;
 868
 869	new_buf = &rx_ring->rx_buf[nta];
 870
 871	/* update, and store next to alloc */
 872	nta++;
 873	rx_ring->next_to_alloc = (nta < rx_ring->count) ? nta : 0;
 874
 875	/* Transfer page from old buffer to new buffer.
 876	 * Move each member individually to avoid possible store
 877	 * forwarding stalls and unnecessary copy of skb.
 878	 */
 879	new_buf->dma = old_buf->dma;
 880	new_buf->page = old_buf->page;
 881	new_buf->page_offset = old_buf->page_offset;
 882	new_buf->pagecnt_bias = old_buf->pagecnt_bias;
 883}
 884
 885/**
 886 * ice_get_rx_buf - Fetch Rx buffer and synchronize data for use
 887 * @rx_ring: Rx descriptor ring to transact packets on
 
 888 * @size: size of buffer to add to skb
 889 * @rx_buf_pgcnt: rx_buf page refcount
 890 *
 891 * This function will pull an Rx buffer from the ring and synchronize it
 892 * for use by the CPU.
 893 */
 894static struct ice_rx_buf *
 895ice_get_rx_buf(struct ice_rx_ring *rx_ring, const unsigned int size,
 896	       int *rx_buf_pgcnt)
 897{
 898	struct ice_rx_buf *rx_buf;
 899
 900	rx_buf = &rx_ring->rx_buf[rx_ring->next_to_clean];
 901	*rx_buf_pgcnt =
 902#if (PAGE_SIZE < 8192)
 903		page_count(rx_buf->page);
 904#else
 905		0;
 906#endif
 907	prefetchw(rx_buf->page);
 
 908
 909	if (!size)
 910		return rx_buf;
 911	/* we are reusing so sync this buffer for CPU use */
 912	dma_sync_single_range_for_cpu(rx_ring->dev, rx_buf->dma,
 913				      rx_buf->page_offset, size,
 914				      DMA_FROM_DEVICE);
 915
 916	/* We have pulled a buffer for use, so decrement pagecnt_bias */
 917	rx_buf->pagecnt_bias--;
 918
 919	return rx_buf;
 920}
 921
 922/**
 923 * ice_build_skb - Build skb around an existing buffer
 924 * @rx_ring: Rx descriptor ring to transact packets on
 925 * @rx_buf: Rx buffer to pull data from
 926 * @xdp: xdp_buff pointing to the data
 927 *
 928 * This function builds an skb around an existing Rx buffer, taking care
 929 * to set up the skb correctly and avoid any memcpy overhead.
 930 */
 931static struct sk_buff *
 932ice_build_skb(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf,
 933	      struct xdp_buff *xdp)
 934{
 935	u8 metasize = xdp->data - xdp->data_meta;
 936#if (PAGE_SIZE < 8192)
 937	unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
 938#else
 939	unsigned int truesize = SKB_DATA_ALIGN(sizeof(struct skb_shared_info)) +
 940				SKB_DATA_ALIGN(xdp->data_end -
 941					       xdp->data_hard_start);
 942#endif
 943	struct sk_buff *skb;
 944
 945	/* Prefetch first cache line of first page. If xdp->data_meta
 946	 * is unused, this points exactly as xdp->data, otherwise we
 947	 * likely have a consumer accessing first few bytes of meta
 948	 * data, and then actual data.
 949	 */
 950	net_prefetch(xdp->data_meta);
 
 
 
 951	/* build an skb around the page buffer */
 952	skb = napi_build_skb(xdp->data_hard_start, truesize);
 953	if (unlikely(!skb))
 954		return NULL;
 955
 956	/* must to record Rx queue, otherwise OS features such as
 957	 * symmetric queue won't work
 958	 */
 959	skb_record_rx_queue(skb, rx_ring->q_index);
 960
 961	/* update pointers within the skb to store the data */
 962	skb_reserve(skb, xdp->data - xdp->data_hard_start);
 963	__skb_put(skb, xdp->data_end - xdp->data);
 964	if (metasize)
 965		skb_metadata_set(skb, metasize);
 966
 967	/* buffer is used by skb, update page_offset */
 968	ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
 969
 970	return skb;
 971}
 972
 973/**
 974 * ice_construct_skb - Allocate skb and populate it
 975 * @rx_ring: Rx descriptor ring to transact packets on
 976 * @rx_buf: Rx buffer to pull data from
 977 * @xdp: xdp_buff pointing to the data
 978 *
 979 * This function allocates an skb. It then populates it with the page
 980 * data from the current receive descriptor, taking care to set up the
 981 * skb correctly.
 982 */
 983static struct sk_buff *
 984ice_construct_skb(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf,
 985		  struct xdp_buff *xdp)
 986{
 987	unsigned int metasize = xdp->data - xdp->data_meta;
 988	unsigned int size = xdp->data_end - xdp->data;
 989	unsigned int headlen;
 990	struct sk_buff *skb;
 991
 992	/* prefetch first cache line of first page */
 993	net_prefetch(xdp->data_meta);
 
 
 
 994
 995	/* allocate a skb to store the frags */
 996	skb = __napi_alloc_skb(&rx_ring->q_vector->napi,
 997			       ICE_RX_HDR_SIZE + metasize,
 998			       GFP_ATOMIC | __GFP_NOWARN);
 999	if (unlikely(!skb))
1000		return NULL;
1001
1002	skb_record_rx_queue(skb, rx_ring->q_index);
1003	/* Determine available headroom for copy */
1004	headlen = size;
1005	if (headlen > ICE_RX_HDR_SIZE)
1006		headlen = eth_get_headlen(skb->dev, xdp->data, ICE_RX_HDR_SIZE);
1007
1008	/* align pull length to size of long to optimize memcpy performance */
1009	memcpy(__skb_put(skb, headlen + metasize), xdp->data_meta,
1010	       ALIGN(headlen + metasize, sizeof(long)));
1011
1012	if (metasize) {
1013		skb_metadata_set(skb, metasize);
1014		__skb_pull(skb, metasize);
1015	}
1016
1017	/* if we exhaust the linear part then add what is left as a frag */
1018	size -= headlen;
1019	if (size) {
1020#if (PAGE_SIZE >= 8192)
1021		unsigned int truesize = SKB_DATA_ALIGN(size);
1022#else
1023		unsigned int truesize = ice_rx_pg_size(rx_ring) / 2;
1024#endif
1025		skb_add_rx_frag(skb, 0, rx_buf->page,
1026				rx_buf->page_offset + headlen, size, truesize);
1027		/* buffer is used by skb, update page_offset */
1028		ice_rx_buf_adjust_pg_offset(rx_buf, truesize);
1029	} else {
1030		/* buffer is unused, reset bias back to rx_buf; data was copied
1031		 * onto skb's linear part so there's no need for adjusting
1032		 * page offset and we can reuse this buffer as-is
1033		 */
1034		rx_buf->pagecnt_bias++;
1035	}
1036
1037	return skb;
1038}
1039
1040/**
1041 * ice_put_rx_buf - Clean up used buffer and either recycle or free
1042 * @rx_ring: Rx descriptor ring to transact packets on
1043 * @rx_buf: Rx buffer to pull data from
1044 * @rx_buf_pgcnt: Rx buffer page count pre xdp_do_redirect()
1045 *
1046 * This function will update next_to_clean and then clean up the contents
1047 * of the rx_buf. It will either recycle the buffer or unmap it and free
1048 * the associated resources.
1049 */
1050static void
1051ice_put_rx_buf(struct ice_rx_ring *rx_ring, struct ice_rx_buf *rx_buf,
1052	       int rx_buf_pgcnt)
1053{
1054	u16 ntc = rx_ring->next_to_clean + 1;
1055
1056	/* fetch, update, and store next to clean */
1057	ntc = (ntc < rx_ring->count) ? ntc : 0;
1058	rx_ring->next_to_clean = ntc;
1059
1060	if (!rx_buf)
1061		return;
1062
1063	if (ice_can_reuse_rx_page(rx_buf, rx_buf_pgcnt)) {
1064		/* hand second half of page back to the ring */
1065		ice_reuse_rx_page(rx_ring, rx_buf);
1066	} else {
1067		/* we are not reusing the buffer so unmap it */
1068		dma_unmap_page_attrs(rx_ring->dev, rx_buf->dma,
1069				     ice_rx_pg_size(rx_ring), DMA_FROM_DEVICE,
1070				     ICE_RX_DMA_ATTR);
1071		__page_frag_cache_drain(rx_buf->page, rx_buf->pagecnt_bias);
1072	}
1073
1074	/* clear contents of buffer_info */
1075	rx_buf->page = NULL;
 
1076}
1077
1078/**
1079 * ice_is_non_eop - process handling of non-EOP buffers
1080 * @rx_ring: Rx ring being processed
1081 * @rx_desc: Rx descriptor for current buffer
 
1082 *
1083 * If the buffer is an EOP buffer, this function exits returning false,
1084 * otherwise return true indicating that this is in fact a non-EOP buffer.
1085 */
1086static bool
1087ice_is_non_eop(struct ice_rx_ring *rx_ring, union ice_32b_rx_flex_desc *rx_desc)
 
1088{
1089	/* if we are the last buffer then there is nothing else to do */
1090#define ICE_RXD_EOF BIT(ICE_RX_FLEX_DESC_STATUS0_EOF_S)
1091	if (likely(ice_test_staterr(rx_desc->wb.status_error0, ICE_RXD_EOF)))
1092		return false;
1093
1094	rx_ring->ring_stats->rx_stats.non_eop_descs++;
 
 
1095
1096	return true;
1097}
1098
1099/**
1100 * ice_clean_rx_irq - Clean completed descriptors from Rx ring - bounce buf
1101 * @rx_ring: Rx descriptor ring to transact packets on
1102 * @budget: Total limit on number of packets to process
1103 *
1104 * This function provides a "bounce buffer" approach to Rx interrupt
1105 * processing. The advantage to this is that on systems that have
1106 * expensive overhead for IOMMU access this provides a means of avoiding
1107 * it by maintaining the mapping of the page to the system.
1108 *
1109 * Returns amount of work completed
1110 */
1111int ice_clean_rx_irq(struct ice_rx_ring *rx_ring, int budget)
1112{
1113	unsigned int total_rx_bytes = 0, total_rx_pkts = 0, frame_sz = 0;
1114	u16 cleaned_count = ICE_DESC_UNUSED(rx_ring);
1115	unsigned int offset = rx_ring->rx_offset;
1116	struct ice_tx_ring *xdp_ring = NULL;
1117	unsigned int xdp_res, xdp_xmit = 0;
1118	struct sk_buff *skb = rx_ring->skb;
1119	struct bpf_prog *xdp_prog = NULL;
1120	struct xdp_buff xdp;
1121	bool failure;
1122
 
1123	/* Frame size depend on rx_ring setup when PAGE_SIZE=4K */
1124#if (PAGE_SIZE < 8192)
1125	frame_sz = ice_rx_frame_truesize(rx_ring, 0);
1126#endif
1127	xdp_init_buff(&xdp, frame_sz, &rx_ring->xdp_rxq);
1128
1129	xdp_prog = READ_ONCE(rx_ring->xdp_prog);
1130	if (xdp_prog)
1131		xdp_ring = rx_ring->xdp_ring;
1132
1133	/* start the loop to process Rx packets bounded by 'budget' */
1134	while (likely(total_rx_pkts < (unsigned int)budget)) {
1135		union ice_32b_rx_flex_desc *rx_desc;
1136		struct ice_rx_buf *rx_buf;
1137		unsigned char *hard_start;
1138		unsigned int size;
1139		u16 stat_err_bits;
1140		int rx_buf_pgcnt;
1141		u16 vlan_tag = 0;
1142		u16 rx_ptype;
1143
1144		/* get the Rx desc from Rx ring based on 'next_to_clean' */
1145		rx_desc = ICE_RX_DESC(rx_ring, rx_ring->next_to_clean);
1146
1147		/* status_error_len will always be zero for unused descriptors
1148		 * because it's cleared in cleanup, and overlaps with hdr_addr
1149		 * which is always zero because packet split isn't used, if the
1150		 * hardware wrote DD then it will be non-zero
1151		 */
1152		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_DD_S);
1153		if (!ice_test_staterr(rx_desc->wb.status_error0, stat_err_bits))
1154			break;
1155
1156		/* This memory barrier is needed to keep us from reading
1157		 * any other fields out of the rx_desc until we know the
1158		 * DD bit is set.
1159		 */
1160		dma_rmb();
1161
1162		ice_trace(clean_rx_irq, rx_ring, rx_desc);
1163		if (rx_desc->wb.rxdid == FDIR_DESC_RXDID || !rx_ring->netdev) {
1164			struct ice_vsi *ctrl_vsi = rx_ring->vsi;
1165
1166			if (rx_desc->wb.rxdid == FDIR_DESC_RXDID &&
1167			    ctrl_vsi->vf)
1168				ice_vc_fdir_irq_handler(ctrl_vsi, rx_desc);
1169			ice_put_rx_buf(rx_ring, NULL, 0);
1170			cleaned_count++;
1171			continue;
1172		}
1173
1174		size = le16_to_cpu(rx_desc->wb.pkt_len) &
1175			ICE_RX_FLX_DESC_PKT_LEN_M;
1176
1177		/* retrieve a buffer from the ring */
1178		rx_buf = ice_get_rx_buf(rx_ring, size, &rx_buf_pgcnt);
1179
1180		if (!size) {
1181			xdp.data = NULL;
1182			xdp.data_end = NULL;
1183			xdp.data_hard_start = NULL;
1184			xdp.data_meta = NULL;
1185			goto construct_skb;
1186		}
1187
1188		hard_start = page_address(rx_buf->page) + rx_buf->page_offset -
1189			     offset;
1190		xdp_prepare_buff(&xdp, hard_start, offset, size, true);
 
1191#if (PAGE_SIZE > 4096)
1192		/* At larger PAGE_SIZE, frame_sz depend on len size */
1193		xdp.frame_sz = ice_rx_frame_truesize(rx_ring, size);
1194#endif
1195
1196		if (!xdp_prog)
 
 
 
1197			goto construct_skb;
 
1198
1199		xdp_res = ice_run_xdp(rx_ring, &xdp, xdp_prog, xdp_ring);
 
1200		if (!xdp_res)
1201			goto construct_skb;
1202		if (xdp_res & (ICE_XDP_TX | ICE_XDP_REDIR)) {
1203			xdp_xmit |= xdp_res;
1204			ice_rx_buf_adjust_pg_offset(rx_buf, xdp.frame_sz);
1205		} else {
1206			rx_buf->pagecnt_bias++;
1207		}
1208		total_rx_bytes += size;
1209		total_rx_pkts++;
1210
1211		cleaned_count++;
1212		ice_put_rx_buf(rx_ring, rx_buf, rx_buf_pgcnt);
1213		continue;
1214construct_skb:
1215		if (skb) {
1216			ice_add_rx_frag(rx_ring, rx_buf, skb, size);
1217		} else if (likely(xdp.data)) {
1218			if (ice_ring_uses_build_skb(rx_ring))
1219				skb = ice_build_skb(rx_ring, rx_buf, &xdp);
1220			else
1221				skb = ice_construct_skb(rx_ring, rx_buf, &xdp);
1222		}
1223		/* exit if we failed to retrieve a buffer */
1224		if (!skb) {
1225			rx_ring->ring_stats->rx_stats.alloc_buf_failed++;
1226			if (rx_buf)
1227				rx_buf->pagecnt_bias++;
1228			break;
1229		}
1230
1231		ice_put_rx_buf(rx_ring, rx_buf, rx_buf_pgcnt);
1232		cleaned_count++;
1233
1234		/* skip if it is NOP desc */
1235		if (ice_is_non_eop(rx_ring, rx_desc))
1236			continue;
1237
1238		stat_err_bits = BIT(ICE_RX_FLEX_DESC_STATUS0_RXE_S);
1239		if (unlikely(ice_test_staterr(rx_desc->wb.status_error0,
1240					      stat_err_bits))) {
1241			dev_kfree_skb_any(skb);
1242			continue;
1243		}
1244
1245		vlan_tag = ice_get_vlan_tag_from_rx_desc(rx_desc);
 
 
1246
1247		/* pad the skb if needed, to make a valid ethernet frame */
1248		if (eth_skb_pad(skb)) {
1249			skb = NULL;
1250			continue;
1251		}
1252
1253		/* probably a little skewed due to removing CRC */
1254		total_rx_bytes += skb->len;
1255
1256		/* populate checksum, VLAN, and protocol */
1257		rx_ptype = le16_to_cpu(rx_desc->wb.ptype_flex_flags0) &
1258			ICE_RX_FLEX_DESC_PTYPE_M;
1259
1260		ice_process_skb_fields(rx_ring, rx_desc, skb, rx_ptype);
1261
1262		ice_trace(clean_rx_irq_indicate, rx_ring, rx_desc, skb);
1263		/* send completed skb up the stack */
1264		ice_receive_skb(rx_ring, skb, vlan_tag);
1265		skb = NULL;
1266
1267		/* update budget accounting */
1268		total_rx_pkts++;
1269	}
1270
1271	/* return up to cleaned_count buffers to hardware */
1272	failure = ice_alloc_rx_bufs(rx_ring, cleaned_count);
1273
1274	if (xdp_prog)
1275		ice_finalize_xdp_rx(xdp_ring, xdp_xmit);
1276	rx_ring->skb = skb;
1277
1278	if (rx_ring->ring_stats)
1279		ice_update_rx_ring_stats(rx_ring, total_rx_pkts,
1280					 total_rx_bytes);
1281
1282	/* guarantee a trip back through this routine if there was a failure */
1283	return failure ? budget : (int)total_rx_pkts;
1284}
1285
1286static void __ice_update_sample(struct ice_q_vector *q_vector,
1287				struct ice_ring_container *rc,
1288				struct dim_sample *sample,
1289				bool is_tx)
1290{
1291	u64 packets = 0, bytes = 0;
1292
1293	if (is_tx) {
1294		struct ice_tx_ring *tx_ring;
1295
1296		ice_for_each_tx_ring(tx_ring, *rc) {
1297			struct ice_ring_stats *ring_stats;
1298
1299			ring_stats = tx_ring->ring_stats;
1300			if (!ring_stats)
1301				continue;
1302			packets += ring_stats->stats.pkts;
1303			bytes += ring_stats->stats.bytes;
1304		}
1305	} else {
1306		struct ice_rx_ring *rx_ring;
1307
1308		ice_for_each_rx_ring(rx_ring, *rc) {
1309			struct ice_ring_stats *ring_stats;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1310
1311			ring_stats = rx_ring->ring_stats;
1312			if (!ring_stats)
1313				continue;
1314			packets += ring_stats->stats.pkts;
1315			bytes += ring_stats->stats.bytes;
1316		}
1317	}
1318
1319	dim_update_sample(q_vector->total_events, packets, bytes, sample);
1320	sample->comp_ctr = 0;
1321
1322	/* if dim settings get stale, like when not updated for 1
1323	 * second or longer, force it to start again. This addresses the
1324	 * frequent case of an idle queue being switched to by the
1325	 * scheduler. The 1,000 here means 1,000 milliseconds.
1326	 */
1327	if (ktime_ms_delta(sample->time, rc->dim.start_sample.time) >= 1000)
1328		rc->dim.state = DIM_START_MEASURE;
1329}
1330
1331/**
1332 * ice_net_dim - Update net DIM algorithm
1333 * @q_vector: the vector associated with the interrupt
 
1334 *
1335 * Create a DIM sample and notify net_dim() so that it can possibly decide
1336 * a new ITR value based on incoming packets, bytes, and interrupts.
1337 *
1338 * This function is a no-op if the ring is not configured to dynamic ITR.
 
 
 
1339 */
1340static void ice_net_dim(struct ice_q_vector *q_vector)
 
1341{
1342	struct ice_ring_container *tx = &q_vector->tx;
1343	struct ice_ring_container *rx = &q_vector->rx;
 
1344
1345	if (ITR_IS_DYNAMIC(tx)) {
1346		struct dim_sample dim_sample;
1347
1348		__ice_update_sample(q_vector, tx, &dim_sample, true);
1349		net_dim(&tx->dim, dim_sample);
 
 
 
 
 
 
 
1350	}
1351
1352	if (ITR_IS_DYNAMIC(rx)) {
1353		struct dim_sample dim_sample;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1354
1355		__ice_update_sample(q_vector, rx, &dim_sample, false);
1356		net_dim(&rx->dim, dim_sample);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1357	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1358}
1359
1360/**
1361 * ice_buildreg_itr - build value for writing to the GLINT_DYN_CTL register
1362 * @itr_idx: interrupt throttling index
1363 * @itr: interrupt throttling value in usecs
1364 */
1365static u32 ice_buildreg_itr(u16 itr_idx, u16 itr)
1366{
1367	/* The ITR value is reported in microseconds, and the register value is
1368	 * recorded in 2 microsecond units. For this reason we only need to
1369	 * shift by the GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S to apply this
1370	 * granularity as a shift instead of division. The mask makes sure the
1371	 * ITR value is never odd so we don't accidentally write into the field
1372	 * prior to the ITR field.
1373	 */
1374	itr &= ICE_ITR_MASK;
1375
1376	return GLINT_DYN_CTL_INTENA_M | GLINT_DYN_CTL_CLEARPBA_M |
1377		(itr_idx << GLINT_DYN_CTL_ITR_INDX_S) |
1378		(itr << (GLINT_DYN_CTL_INTERVAL_S - ICE_ITR_GRAN_S));
1379}
1380
 
 
 
 
 
 
 
 
 
1381/**
1382 * ice_enable_interrupt - re-enable MSI-X interrupt
1383 * @q_vector: the vector associated with the interrupt to enable
1384 *
1385 * If the VSI is down, the interrupt will not be re-enabled. Also,
1386 * when enabling the interrupt always reset the wb_on_itr to false
1387 * and trigger a software interrupt to clean out internal state.
1388 */
1389static void ice_enable_interrupt(struct ice_q_vector *q_vector)
1390{
 
 
1391	struct ice_vsi *vsi = q_vector->vsi;
1392	bool wb_en = q_vector->wb_on_itr;
1393	u32 itr_val;
1394
1395	if (test_bit(ICE_DOWN, vsi->state))
 
 
 
 
 
 
 
 
 
 
 
 
 
1396		return;
 
1397
1398	/* trigger an ITR delayed software interrupt when exiting busy poll, to
1399	 * make sure to catch any pending cleanups that might have been missed
1400	 * due to interrupt state transition. If busy poll or poll isn't
1401	 * enabled, then don't update ITR, and just enable the interrupt.
 
 
 
 
 
 
 
1402	 */
1403	if (!wb_en) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1404		itr_val = ice_buildreg_itr(ICE_ITR_NONE, 0);
1405	} else {
1406		q_vector->wb_on_itr = false;
 
1407
1408		/* do two things here with a single write. Set up the third ITR
1409		 * index to be used for software interrupt moderation, and then
1410		 * trigger a software interrupt with a rate limit of 20K on
1411		 * software interrupts, this will help avoid high interrupt
1412		 * loads due to frequently polling and exiting polling.
1413		 */
1414		itr_val = ice_buildreg_itr(ICE_IDX_ITR2, ICE_ITR_20K);
1415		itr_val |= GLINT_DYN_CTL_SWINT_TRIG_M |
1416			   ICE_IDX_ITR2 << GLINT_DYN_CTL_SW_ITR_INDX_S |
1417			   GLINT_DYN_CTL_SW_ITR_INDX_ENA_M;
1418	}
1419	wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx), itr_val);
1420}
1421
1422/**
1423 * ice_set_wb_on_itr - set WB_ON_ITR for this q_vector
1424 * @q_vector: q_vector to set WB_ON_ITR on
1425 *
1426 * We need to tell hardware to write-back completed descriptors even when
1427 * interrupts are disabled. Descriptors will be written back on cache line
1428 * boundaries without WB_ON_ITR enabled, but if we don't enable WB_ON_ITR
1429 * descriptors may not be written back if they don't fill a cache line until
1430 * the next interrupt.
1431 *
1432 * This sets the write-back frequency to whatever was set previously for the
1433 * ITR indices. Also, set the INTENA_MSK bit to make sure hardware knows we
1434 * aren't meddling with the INTENA_M bit.
1435 */
1436static void ice_set_wb_on_itr(struct ice_q_vector *q_vector)
1437{
1438	struct ice_vsi *vsi = q_vector->vsi;
1439
1440	/* already in wb_on_itr mode no need to change it */
1441	if (q_vector->wb_on_itr)
1442		return;
1443
1444	/* use previously set ITR values for all of the ITR indices by
1445	 * specifying ICE_ITR_NONE, which will vary in adaptive (AIM) mode and
1446	 * be static in non-adaptive mode (user configured)
1447	 */
1448	wr32(&vsi->back->hw, GLINT_DYN_CTL(q_vector->reg_idx),
1449	     ((ICE_ITR_NONE << GLINT_DYN_CTL_ITR_INDX_S) &
1450	      GLINT_DYN_CTL_ITR_INDX_M) | GLINT_DYN_CTL_INTENA_MSK_M |
1451	     GLINT_DYN_CTL_WB_ON_ITR_M);
 
1452
1453	q_vector->wb_on_itr = true;
1454}
1455
1456/**
1457 * ice_napi_poll - NAPI polling Rx/Tx cleanup routine
1458 * @napi: napi struct with our devices info in it
1459 * @budget: amount of work driver is allowed to do this pass, in packets
1460 *
1461 * This function will clean all queues associated with a q_vector.
1462 *
1463 * Returns the amount of work done
1464 */
1465int ice_napi_poll(struct napi_struct *napi, int budget)
1466{
1467	struct ice_q_vector *q_vector =
1468				container_of(napi, struct ice_q_vector, napi);
1469	struct ice_tx_ring *tx_ring;
1470	struct ice_rx_ring *rx_ring;
1471	bool clean_complete = true;
 
1472	int budget_per_ring;
1473	int work_done = 0;
1474
1475	/* Since the actual Tx work is minimal, we can give the Tx a larger
1476	 * budget and be more aggressive about cleaning up the Tx descriptors.
1477	 */
1478	ice_for_each_tx_ring(tx_ring, q_vector->tx) {
1479		bool wd;
1480
1481		if (tx_ring->xsk_pool)
1482			wd = ice_xmit_zc(tx_ring);
1483		else if (ice_ring_is_xdp(tx_ring))
1484			wd = true;
1485		else
1486			wd = ice_clean_tx_irq(tx_ring, budget);
1487
1488		if (!wd)
1489			clean_complete = false;
1490	}
1491
1492	/* Handle case where we are called by netpoll with a budget of 0 */
1493	if (unlikely(budget <= 0))
1494		return budget;
1495
1496	/* normally we have 1 Rx ring per q_vector */
1497	if (unlikely(q_vector->num_ring_rx > 1))
1498		/* We attempt to distribute budget to each Rx queue fairly, but
1499		 * don't allow the budget to go below 1 because that would exit
1500		 * polling early.
1501		 */
1502		budget_per_ring = max_t(int, budget / q_vector->num_ring_rx, 1);
1503	else
1504		/* Max of 1 Rx ring in this q_vector so give it the budget */
1505		budget_per_ring = budget;
1506
1507	ice_for_each_rx_ring(rx_ring, q_vector->rx) {
1508		int cleaned;
1509
1510		/* A dedicated path for zero-copy allows making a single
1511		 * comparison in the irq context instead of many inside the
1512		 * ice_clean_rx_irq function and makes the codebase cleaner.
1513		 */
1514		cleaned = rx_ring->xsk_pool ?
1515			  ice_clean_rx_irq_zc(rx_ring, budget_per_ring) :
1516			  ice_clean_rx_irq(rx_ring, budget_per_ring);
1517		work_done += cleaned;
1518		/* if we clean as many as budgeted, we must not be done */
1519		if (cleaned >= budget_per_ring)
1520			clean_complete = false;
1521	}
1522
1523	/* If work not completed, return budget and polling will return */
1524	if (!clean_complete) {
1525		/* Set the writeback on ITR so partial completions of
1526		 * cache-lines will still continue even if we're polling.
1527		 */
1528		ice_set_wb_on_itr(q_vector);
1529		return budget;
1530	}
1531
1532	/* Exit the polling mode, but don't re-enable interrupts if stack might
1533	 * poll us due to busy-polling
1534	 */
1535	if (napi_complete_done(napi, work_done)) {
1536		ice_net_dim(q_vector);
1537		ice_enable_interrupt(q_vector);
1538	} else {
1539		ice_set_wb_on_itr(q_vector);
1540	}
1541
1542	return min_t(int, work_done, budget - 1);
1543}
1544
1545/**
1546 * __ice_maybe_stop_tx - 2nd level check for Tx stop conditions
1547 * @tx_ring: the ring to be checked
1548 * @size: the size buffer we want to assure is available
1549 *
1550 * Returns -EBUSY if a stop is needed, else 0
1551 */
1552static int __ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
1553{
1554	netif_tx_stop_queue(txring_txq(tx_ring));
1555	/* Memory barrier before checking head and tail */
1556	smp_mb();
1557
1558	/* Check again in a case another CPU has just made room available. */
1559	if (likely(ICE_DESC_UNUSED(tx_ring) < size))
1560		return -EBUSY;
1561
1562	/* A reprieve! - use start_queue because it doesn't call schedule */
1563	netif_tx_start_queue(txring_txq(tx_ring));
1564	++tx_ring->ring_stats->tx_stats.restart_q;
1565	return 0;
1566}
1567
1568/**
1569 * ice_maybe_stop_tx - 1st level check for Tx stop conditions
1570 * @tx_ring: the ring to be checked
1571 * @size:    the size buffer we want to assure is available
1572 *
1573 * Returns 0 if stop is not needed
1574 */
1575static int ice_maybe_stop_tx(struct ice_tx_ring *tx_ring, unsigned int size)
1576{
1577	if (likely(ICE_DESC_UNUSED(tx_ring) >= size))
1578		return 0;
1579
1580	return __ice_maybe_stop_tx(tx_ring, size);
1581}
1582
1583/**
1584 * ice_tx_map - Build the Tx descriptor
1585 * @tx_ring: ring to send buffer on
1586 * @first: first buffer info buffer to use
1587 * @off: pointer to struct that holds offload parameters
1588 *
1589 * This function loops over the skb data pointed to by *first
1590 * and gets a physical address for each memory location and programs
1591 * it and the length into the transmit descriptor.
1592 */
1593static void
1594ice_tx_map(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first,
1595	   struct ice_tx_offload_params *off)
1596{
1597	u64 td_offset, td_tag, td_cmd;
1598	u16 i = tx_ring->next_to_use;
1599	unsigned int data_len, size;
1600	struct ice_tx_desc *tx_desc;
1601	struct ice_tx_buf *tx_buf;
1602	struct sk_buff *skb;
1603	skb_frag_t *frag;
1604	dma_addr_t dma;
1605	bool kick;
1606
1607	td_tag = off->td_l2tag1;
1608	td_cmd = off->td_cmd;
1609	td_offset = off->td_offset;
1610	skb = first->skb;
1611
1612	data_len = skb->data_len;
1613	size = skb_headlen(skb);
1614
1615	tx_desc = ICE_TX_DESC(tx_ring, i);
1616
1617	if (first->tx_flags & ICE_TX_FLAGS_HW_VLAN) {
1618		td_cmd |= (u64)ICE_TX_DESC_CMD_IL2TAG1;
1619		td_tag = (first->tx_flags & ICE_TX_FLAGS_VLAN_M) >>
1620			  ICE_TX_FLAGS_VLAN_S;
1621	}
1622
1623	dma = dma_map_single(tx_ring->dev, skb->data, size, DMA_TO_DEVICE);
1624
1625	tx_buf = first;
1626
1627	for (frag = &skb_shinfo(skb)->frags[0];; frag++) {
1628		unsigned int max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1629
1630		if (dma_mapping_error(tx_ring->dev, dma))
1631			goto dma_error;
1632
1633		/* record length, and DMA address */
1634		dma_unmap_len_set(tx_buf, len, size);
1635		dma_unmap_addr_set(tx_buf, dma, dma);
1636
1637		/* align size to end of page */
1638		max_data += -dma & (ICE_MAX_READ_REQ_SIZE - 1);
1639		tx_desc->buf_addr = cpu_to_le64(dma);
1640
1641		/* account for data chunks larger than the hardware
1642		 * can handle
1643		 */
1644		while (unlikely(size > ICE_MAX_DATA_PER_TXD)) {
1645			tx_desc->cmd_type_offset_bsz =
1646				ice_build_ctob(td_cmd, td_offset, max_data,
1647					       td_tag);
1648
1649			tx_desc++;
1650			i++;
1651
1652			if (i == tx_ring->count) {
1653				tx_desc = ICE_TX_DESC(tx_ring, 0);
1654				i = 0;
1655			}
1656
1657			dma += max_data;
1658			size -= max_data;
1659
1660			max_data = ICE_MAX_DATA_PER_TXD_ALIGNED;
1661			tx_desc->buf_addr = cpu_to_le64(dma);
1662		}
1663
1664		if (likely(!data_len))
1665			break;
1666
1667		tx_desc->cmd_type_offset_bsz = ice_build_ctob(td_cmd, td_offset,
1668							      size, td_tag);
1669
1670		tx_desc++;
1671		i++;
1672
1673		if (i == tx_ring->count) {
1674			tx_desc = ICE_TX_DESC(tx_ring, 0);
1675			i = 0;
1676		}
1677
1678		size = skb_frag_size(frag);
1679		data_len -= size;
1680
1681		dma = skb_frag_dma_map(tx_ring->dev, frag, 0, size,
1682				       DMA_TO_DEVICE);
1683
1684		tx_buf = &tx_ring->tx_buf[i];
1685	}
1686
 
 
 
1687	/* record SW timestamp if HW timestamp is not available */
1688	skb_tx_timestamp(first->skb);
1689
1690	i++;
1691	if (i == tx_ring->count)
1692		i = 0;
1693
1694	/* write last descriptor with RS and EOP bits */
1695	td_cmd |= (u64)ICE_TXD_LAST_DESC_CMD;
1696	tx_desc->cmd_type_offset_bsz =
1697			ice_build_ctob(td_cmd, td_offset, size, td_tag);
1698
1699	/* Force memory writes to complete before letting h/w know there
1700	 * are new descriptors to fetch.
1701	 *
1702	 * We also use this memory barrier to make certain all of the
1703	 * status bits have been updated before next_to_watch is written.
1704	 */
1705	wmb();
1706
1707	/* set next_to_watch value indicating a packet is present */
1708	first->next_to_watch = tx_desc;
1709
1710	tx_ring->next_to_use = i;
1711
1712	ice_maybe_stop_tx(tx_ring, DESC_NEEDED);
1713
1714	/* notify HW of packet */
1715	kick = __netdev_tx_sent_queue(txring_txq(tx_ring), first->bytecount,
1716				      netdev_xmit_more());
1717	if (kick)
1718		/* notify HW of packet */
1719		writel(i, tx_ring->tail);
1720
1721	return;
1722
1723dma_error:
1724	/* clear DMA mappings for failed tx_buf map */
1725	for (;;) {
1726		tx_buf = &tx_ring->tx_buf[i];
1727		ice_unmap_and_free_tx_buf(tx_ring, tx_buf);
1728		if (tx_buf == first)
1729			break;
1730		if (i == 0)
1731			i = tx_ring->count;
1732		i--;
1733	}
1734
1735	tx_ring->next_to_use = i;
1736}
1737
1738/**
1739 * ice_tx_csum - Enable Tx checksum offloads
1740 * @first: pointer to the first descriptor
1741 * @off: pointer to struct that holds offload parameters
1742 *
1743 * Returns 0 or error (negative) if checksum offload can't happen, 1 otherwise.
1744 */
1745static
1746int ice_tx_csum(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
1747{
1748	u32 l4_len = 0, l3_len = 0, l2_len = 0;
1749	struct sk_buff *skb = first->skb;
1750	union {
1751		struct iphdr *v4;
1752		struct ipv6hdr *v6;
1753		unsigned char *hdr;
1754	} ip;
1755	union {
1756		struct tcphdr *tcp;
1757		unsigned char *hdr;
1758	} l4;
1759	__be16 frag_off, protocol;
1760	unsigned char *exthdr;
1761	u32 offset, cmd = 0;
1762	u8 l4_proto = 0;
1763
1764	if (skb->ip_summed != CHECKSUM_PARTIAL)
1765		return 0;
1766
1767	protocol = vlan_get_protocol(skb);
1768
1769	if (eth_p_mpls(protocol)) {
1770		ip.hdr = skb_inner_network_header(skb);
1771		l4.hdr = skb_checksum_start(skb);
1772	} else {
1773		ip.hdr = skb_network_header(skb);
1774		l4.hdr = skb_transport_header(skb);
1775	}
1776
1777	/* compute outer L2 header size */
1778	l2_len = ip.hdr - skb->data;
1779	offset = (l2_len / 2) << ICE_TX_DESC_LEN_MACLEN_S;
1780
1781	/* set the tx_flags to indicate the IP protocol type. this is
1782	 * required so that checksum header computation below is accurate.
1783	 */
1784	if (ip.v4->version == 4)
1785		first->tx_flags |= ICE_TX_FLAGS_IPV4;
1786	else if (ip.v6->version == 6)
1787		first->tx_flags |= ICE_TX_FLAGS_IPV6;
1788
1789	if (skb->encapsulation) {
1790		bool gso_ena = false;
1791		u32 tunnel = 0;
1792
1793		/* define outer network header type */
1794		if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1795			tunnel |= (first->tx_flags & ICE_TX_FLAGS_TSO) ?
1796				  ICE_TX_CTX_EIPT_IPV4 :
1797				  ICE_TX_CTX_EIPT_IPV4_NO_CSUM;
1798			l4_proto = ip.v4->protocol;
1799		} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
1800			int ret;
1801
1802			tunnel |= ICE_TX_CTX_EIPT_IPV6;
1803			exthdr = ip.hdr + sizeof(*ip.v6);
1804			l4_proto = ip.v6->nexthdr;
1805			ret = ipv6_skip_exthdr(skb, exthdr - skb->data,
1806					       &l4_proto, &frag_off);
1807			if (ret < 0)
1808				return -1;
1809		}
1810
1811		/* define outer transport */
1812		switch (l4_proto) {
1813		case IPPROTO_UDP:
1814			tunnel |= ICE_TXD_CTX_UDP_TUNNELING;
1815			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1816			break;
1817		case IPPROTO_GRE:
1818			tunnel |= ICE_TXD_CTX_GRE_TUNNELING;
1819			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1820			break;
1821		case IPPROTO_IPIP:
1822		case IPPROTO_IPV6:
1823			first->tx_flags |= ICE_TX_FLAGS_TUNNEL;
1824			l4.hdr = skb_inner_network_header(skb);
1825			break;
1826		default:
1827			if (first->tx_flags & ICE_TX_FLAGS_TSO)
1828				return -1;
1829
1830			skb_checksum_help(skb);
1831			return 0;
1832		}
1833
1834		/* compute outer L3 header size */
1835		tunnel |= ((l4.hdr - ip.hdr) / 4) <<
1836			  ICE_TXD_CTX_QW0_EIPLEN_S;
1837
1838		/* switch IP header pointer from outer to inner header */
1839		ip.hdr = skb_inner_network_header(skb);
1840
1841		/* compute tunnel header size */
1842		tunnel |= ((ip.hdr - l4.hdr) / 2) <<
1843			   ICE_TXD_CTX_QW0_NATLEN_S;
1844
1845		gso_ena = skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL;
1846		/* indicate if we need to offload outer UDP header */
1847		if ((first->tx_flags & ICE_TX_FLAGS_TSO) && !gso_ena &&
1848		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM))
1849			tunnel |= ICE_TXD_CTX_QW0_L4T_CS_M;
1850
1851		/* record tunnel offload values */
1852		off->cd_tunnel_params |= tunnel;
1853
1854		/* set DTYP=1 to indicate that it's an Tx context descriptor
1855		 * in IPsec tunnel mode with Tx offloads in Quad word 1
1856		 */
1857		off->cd_qw1 |= (u64)ICE_TX_DESC_DTYPE_CTX;
1858
1859		/* switch L4 header pointer from outer to inner */
1860		l4.hdr = skb_inner_transport_header(skb);
1861		l4_proto = 0;
1862
1863		/* reset type as we transition from outer to inner headers */
1864		first->tx_flags &= ~(ICE_TX_FLAGS_IPV4 | ICE_TX_FLAGS_IPV6);
1865		if (ip.v4->version == 4)
1866			first->tx_flags |= ICE_TX_FLAGS_IPV4;
1867		if (ip.v6->version == 6)
1868			first->tx_flags |= ICE_TX_FLAGS_IPV6;
1869	}
1870
1871	/* Enable IP checksum offloads */
1872	if (first->tx_flags & ICE_TX_FLAGS_IPV4) {
1873		l4_proto = ip.v4->protocol;
1874		/* the stack computes the IP header already, the only time we
1875		 * need the hardware to recompute it is in the case of TSO.
1876		 */
1877		if (first->tx_flags & ICE_TX_FLAGS_TSO)
1878			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4_CSUM;
1879		else
1880			cmd |= ICE_TX_DESC_CMD_IIPT_IPV4;
1881
1882	} else if (first->tx_flags & ICE_TX_FLAGS_IPV6) {
1883		cmd |= ICE_TX_DESC_CMD_IIPT_IPV6;
1884		exthdr = ip.hdr + sizeof(*ip.v6);
1885		l4_proto = ip.v6->nexthdr;
1886		if (l4.hdr != exthdr)
1887			ipv6_skip_exthdr(skb, exthdr - skb->data, &l4_proto,
1888					 &frag_off);
1889	} else {
1890		return -1;
1891	}
1892
1893	/* compute inner L3 header size */
1894	l3_len = l4.hdr - ip.hdr;
1895	offset |= (l3_len / 4) << ICE_TX_DESC_LEN_IPLEN_S;
1896
1897	/* Enable L4 checksum offloads */
1898	switch (l4_proto) {
1899	case IPPROTO_TCP:
1900		/* enable checksum offloads */
1901		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_TCP;
1902		l4_len = l4.tcp->doff;
1903		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
1904		break;
1905	case IPPROTO_UDP:
1906		/* enable UDP checksum offload */
1907		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_UDP;
1908		l4_len = (sizeof(struct udphdr) >> 2);
1909		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
1910		break;
1911	case IPPROTO_SCTP:
1912		/* enable SCTP checksum offload */
1913		cmd |= ICE_TX_DESC_CMD_L4T_EOFT_SCTP;
1914		l4_len = sizeof(struct sctphdr) >> 2;
1915		offset |= l4_len << ICE_TX_DESC_LEN_L4_LEN_S;
1916		break;
1917
1918	default:
1919		if (first->tx_flags & ICE_TX_FLAGS_TSO)
1920			return -1;
1921		skb_checksum_help(skb);
1922		return 0;
1923	}
1924
1925	off->td_cmd |= cmd;
1926	off->td_offset |= offset;
1927	return 1;
1928}
1929
1930/**
1931 * ice_tx_prepare_vlan_flags - prepare generic Tx VLAN tagging flags for HW
1932 * @tx_ring: ring to send buffer on
1933 * @first: pointer to struct ice_tx_buf
1934 *
1935 * Checks the skb and set up correspondingly several generic transmit flags
1936 * related to VLAN tagging for the HW, such as VLAN, DCB, etc.
1937 */
1938static void
1939ice_tx_prepare_vlan_flags(struct ice_tx_ring *tx_ring, struct ice_tx_buf *first)
1940{
1941	struct sk_buff *skb = first->skb;
1942
1943	/* nothing left to do, software offloaded VLAN */
1944	if (!skb_vlan_tag_present(skb) && eth_type_vlan(skb->protocol))
1945		return;
1946
1947	/* the VLAN ethertype/tpid is determined by VSI configuration and netdev
1948	 * feature flags, which the driver only allows either 802.1Q or 802.1ad
1949	 * VLAN offloads exclusively so we only care about the VLAN ID here
1950	 */
1951	if (skb_vlan_tag_present(skb)) {
1952		first->tx_flags |= skb_vlan_tag_get(skb) << ICE_TX_FLAGS_VLAN_S;
1953		if (tx_ring->flags & ICE_TX_FLAGS_RING_VLAN_L2TAG2)
1954			first->tx_flags |= ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN;
1955		else
1956			first->tx_flags |= ICE_TX_FLAGS_HW_VLAN;
1957	}
1958
1959	ice_tx_prepare_vlan_flags_dcb(tx_ring, first);
1960}
1961
1962/**
1963 * ice_tso - computes mss and TSO length to prepare for TSO
1964 * @first: pointer to struct ice_tx_buf
1965 * @off: pointer to struct that holds offload parameters
1966 *
1967 * Returns 0 or error (negative) if TSO can't happen, 1 otherwise.
1968 */
1969static
1970int ice_tso(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
1971{
1972	struct sk_buff *skb = first->skb;
1973	union {
1974		struct iphdr *v4;
1975		struct ipv6hdr *v6;
1976		unsigned char *hdr;
1977	} ip;
1978	union {
1979		struct tcphdr *tcp;
1980		struct udphdr *udp;
1981		unsigned char *hdr;
1982	} l4;
1983	u64 cd_mss, cd_tso_len;
1984	__be16 protocol;
1985	u32 paylen;
1986	u8 l4_start;
1987	int err;
1988
1989	if (skb->ip_summed != CHECKSUM_PARTIAL)
1990		return 0;
1991
1992	if (!skb_is_gso(skb))
1993		return 0;
1994
1995	err = skb_cow_head(skb, 0);
1996	if (err < 0)
1997		return err;
1998
1999	/* cppcheck-suppress unreadVariable */
2000	protocol = vlan_get_protocol(skb);
2001
2002	if (eth_p_mpls(protocol))
2003		ip.hdr = skb_inner_network_header(skb);
2004	else
2005		ip.hdr = skb_network_header(skb);
2006	l4.hdr = skb_checksum_start(skb);
2007
2008	/* initialize outer IP header fields */
2009	if (ip.v4->version == 4) {
2010		ip.v4->tot_len = 0;
2011		ip.v4->check = 0;
2012	} else {
2013		ip.v6->payload_len = 0;
2014	}
2015
2016	if (skb_shinfo(skb)->gso_type & (SKB_GSO_GRE |
2017					 SKB_GSO_GRE_CSUM |
2018					 SKB_GSO_IPXIP4 |
2019					 SKB_GSO_IPXIP6 |
2020					 SKB_GSO_UDP_TUNNEL |
2021					 SKB_GSO_UDP_TUNNEL_CSUM)) {
2022		if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
2023		    (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
2024			l4.udp->len = 0;
2025
2026			/* determine offset of outer transport header */
2027			l4_start = (u8)(l4.hdr - skb->data);
2028
2029			/* remove payload length from outer checksum */
2030			paylen = skb->len - l4_start;
2031			csum_replace_by_diff(&l4.udp->check,
2032					     (__force __wsum)htonl(paylen));
2033		}
2034
2035		/* reset pointers to inner headers */
2036
2037		/* cppcheck-suppress unreadVariable */
2038		ip.hdr = skb_inner_network_header(skb);
2039		l4.hdr = skb_inner_transport_header(skb);
2040
2041		/* initialize inner IP header fields */
2042		if (ip.v4->version == 4) {
2043			ip.v4->tot_len = 0;
2044			ip.v4->check = 0;
2045		} else {
2046			ip.v6->payload_len = 0;
2047		}
2048	}
2049
2050	/* determine offset of transport header */
2051	l4_start = (u8)(l4.hdr - skb->data);
2052
2053	/* remove payload length from checksum */
2054	paylen = skb->len - l4_start;
2055
2056	if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP_L4) {
2057		csum_replace_by_diff(&l4.udp->check,
2058				     (__force __wsum)htonl(paylen));
2059		/* compute length of UDP segmentation header */
2060		off->header_len = (u8)sizeof(l4.udp) + l4_start;
2061	} else {
2062		csum_replace_by_diff(&l4.tcp->check,
2063				     (__force __wsum)htonl(paylen));
2064		/* compute length of TCP segmentation header */
2065		off->header_len = (u8)((l4.tcp->doff * 4) + l4_start);
2066	}
2067
2068	/* update gso_segs and bytecount */
2069	first->gso_segs = skb_shinfo(skb)->gso_segs;
2070	first->bytecount += (first->gso_segs - 1) * off->header_len;
2071
2072	cd_tso_len = skb->len - off->header_len;
2073	cd_mss = skb_shinfo(skb)->gso_size;
2074
2075	/* record cdesc_qw1 with TSO parameters */
2076	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2077			     (ICE_TX_CTX_DESC_TSO << ICE_TXD_CTX_QW1_CMD_S) |
2078			     (cd_tso_len << ICE_TXD_CTX_QW1_TSO_LEN_S) |
2079			     (cd_mss << ICE_TXD_CTX_QW1_MSS_S));
2080	first->tx_flags |= ICE_TX_FLAGS_TSO;
2081	return 1;
2082}
2083
2084/**
2085 * ice_txd_use_count  - estimate the number of descriptors needed for Tx
2086 * @size: transmit request size in bytes
2087 *
2088 * Due to hardware alignment restrictions (4K alignment), we need to
2089 * assume that we can have no more than 12K of data per descriptor, even
2090 * though each descriptor can take up to 16K - 1 bytes of aligned memory.
2091 * Thus, we need to divide by 12K. But division is slow! Instead,
2092 * we decompose the operation into shifts and one relatively cheap
2093 * multiply operation.
2094 *
2095 * To divide by 12K, we first divide by 4K, then divide by 3:
2096 *     To divide by 4K, shift right by 12 bits
2097 *     To divide by 3, multiply by 85, then divide by 256
2098 *     (Divide by 256 is done by shifting right by 8 bits)
2099 * Finally, we add one to round up. Because 256 isn't an exact multiple of
2100 * 3, we'll underestimate near each multiple of 12K. This is actually more
2101 * accurate as we have 4K - 1 of wiggle room that we can fit into the last
2102 * segment. For our purposes this is accurate out to 1M which is orders of
2103 * magnitude greater than our largest possible GSO size.
2104 *
2105 * This would then be implemented as:
2106 *     return (((size >> 12) * 85) >> 8) + ICE_DESCS_FOR_SKB_DATA_PTR;
2107 *
2108 * Since multiplication and division are commutative, we can reorder
2109 * operations into:
2110 *     return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2111 */
2112static unsigned int ice_txd_use_count(unsigned int size)
2113{
2114	return ((size * 85) >> 20) + ICE_DESCS_FOR_SKB_DATA_PTR;
2115}
2116
2117/**
2118 * ice_xmit_desc_count - calculate number of Tx descriptors needed
2119 * @skb: send buffer
2120 *
2121 * Returns number of data descriptors needed for this skb.
2122 */
2123static unsigned int ice_xmit_desc_count(struct sk_buff *skb)
2124{
2125	const skb_frag_t *frag = &skb_shinfo(skb)->frags[0];
2126	unsigned int nr_frags = skb_shinfo(skb)->nr_frags;
2127	unsigned int count = 0, size = skb_headlen(skb);
2128
2129	for (;;) {
2130		count += ice_txd_use_count(size);
2131
2132		if (!nr_frags--)
2133			break;
2134
2135		size = skb_frag_size(frag++);
2136	}
2137
2138	return count;
2139}
2140
2141/**
2142 * __ice_chk_linearize - Check if there are more than 8 buffers per packet
2143 * @skb: send buffer
2144 *
2145 * Note: This HW can't DMA more than 8 buffers to build a packet on the wire
2146 * and so we need to figure out the cases where we need to linearize the skb.
2147 *
2148 * For TSO we need to count the TSO header and segment payload separately.
2149 * As such we need to check cases where we have 7 fragments or more as we
2150 * can potentially require 9 DMA transactions, 1 for the TSO header, 1 for
2151 * the segment payload in the first descriptor, and another 7 for the
2152 * fragments.
2153 */
2154static bool __ice_chk_linearize(struct sk_buff *skb)
2155{
2156	const skb_frag_t *frag, *stale;
2157	int nr_frags, sum;
2158
2159	/* no need to check if number of frags is less than 7 */
2160	nr_frags = skb_shinfo(skb)->nr_frags;
2161	if (nr_frags < (ICE_MAX_BUF_TXD - 1))
2162		return false;
2163
2164	/* We need to walk through the list and validate that each group
2165	 * of 6 fragments totals at least gso_size.
2166	 */
2167	nr_frags -= ICE_MAX_BUF_TXD - 2;
2168	frag = &skb_shinfo(skb)->frags[0];
2169
2170	/* Initialize size to the negative value of gso_size minus 1. We
2171	 * use this as the worst case scenario in which the frag ahead
2172	 * of us only provides one byte which is why we are limited to 6
2173	 * descriptors for a single transmit as the header and previous
2174	 * fragment are already consuming 2 descriptors.
2175	 */
2176	sum = 1 - skb_shinfo(skb)->gso_size;
2177
2178	/* Add size of frags 0 through 4 to create our initial sum */
2179	sum += skb_frag_size(frag++);
2180	sum += skb_frag_size(frag++);
2181	sum += skb_frag_size(frag++);
2182	sum += skb_frag_size(frag++);
2183	sum += skb_frag_size(frag++);
2184
2185	/* Walk through fragments adding latest fragment, testing it, and
2186	 * then removing stale fragments from the sum.
2187	 */
2188	for (stale = &skb_shinfo(skb)->frags[0];; stale++) {
2189		int stale_size = skb_frag_size(stale);
2190
2191		sum += skb_frag_size(frag++);
2192
2193		/* The stale fragment may present us with a smaller
2194		 * descriptor than the actual fragment size. To account
2195		 * for that we need to remove all the data on the front and
2196		 * figure out what the remainder would be in the last
2197		 * descriptor associated with the fragment.
2198		 */
2199		if (stale_size > ICE_MAX_DATA_PER_TXD) {
2200			int align_pad = -(skb_frag_off(stale)) &
2201					(ICE_MAX_READ_REQ_SIZE - 1);
2202
2203			sum -= align_pad;
2204			stale_size -= align_pad;
2205
2206			do {
2207				sum -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2208				stale_size -= ICE_MAX_DATA_PER_TXD_ALIGNED;
2209			} while (stale_size > ICE_MAX_DATA_PER_TXD);
2210		}
2211
2212		/* if sum is negative we failed to make sufficient progress */
2213		if (sum < 0)
2214			return true;
2215
2216		if (!nr_frags--)
2217			break;
2218
2219		sum -= stale_size;
2220	}
2221
2222	return false;
2223}
2224
2225/**
2226 * ice_chk_linearize - Check if there are more than 8 fragments per packet
2227 * @skb:      send buffer
2228 * @count:    number of buffers used
2229 *
2230 * Note: Our HW can't scatter-gather more than 8 fragments to build
2231 * a packet on the wire and so we need to figure out the cases where we
2232 * need to linearize the skb.
2233 */
2234static bool ice_chk_linearize(struct sk_buff *skb, unsigned int count)
2235{
2236	/* Both TSO and single send will work if count is less than 8 */
2237	if (likely(count < ICE_MAX_BUF_TXD))
2238		return false;
2239
2240	if (skb_is_gso(skb))
2241		return __ice_chk_linearize(skb);
2242
2243	/* we can support up to 8 data buffers for a single send */
2244	return count != ICE_MAX_BUF_TXD;
2245}
2246
2247/**
2248 * ice_tstamp - set up context descriptor for hardware timestamp
2249 * @tx_ring: pointer to the Tx ring to send buffer on
2250 * @skb: pointer to the SKB we're sending
2251 * @first: Tx buffer
2252 * @off: Tx offload parameters
2253 */
2254static void
2255ice_tstamp(struct ice_tx_ring *tx_ring, struct sk_buff *skb,
2256	   struct ice_tx_buf *first, struct ice_tx_offload_params *off)
2257{
2258	s8 idx;
2259
2260	/* only timestamp the outbound packet if the user has requested it */
2261	if (likely(!(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)))
2262		return;
2263
2264	if (!tx_ring->ptp_tx)
2265		return;
2266
2267	/* Tx timestamps cannot be sampled when doing TSO */
2268	if (first->tx_flags & ICE_TX_FLAGS_TSO)
2269		return;
2270
2271	/* Grab an open timestamp slot */
2272	idx = ice_ptp_request_ts(tx_ring->tx_tstamps, skb);
2273	if (idx < 0) {
2274		tx_ring->vsi->back->ptp.tx_hwtstamp_skipped++;
2275		return;
2276	}
2277
2278	off->cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2279			     (ICE_TX_CTX_DESC_TSYN << ICE_TXD_CTX_QW1_CMD_S) |
2280			     ((u64)idx << ICE_TXD_CTX_QW1_TSO_LEN_S));
2281	first->tx_flags |= ICE_TX_FLAGS_TSYN;
2282}
2283
2284/**
2285 * ice_xmit_frame_ring - Sends buffer on Tx ring
2286 * @skb: send buffer
2287 * @tx_ring: ring to send buffer on
2288 *
2289 * Returns NETDEV_TX_OK if sent, else an error code
2290 */
2291static netdev_tx_t
2292ice_xmit_frame_ring(struct sk_buff *skb, struct ice_tx_ring *tx_ring)
2293{
2294	struct ice_tx_offload_params offload = { 0 };
2295	struct ice_vsi *vsi = tx_ring->vsi;
2296	struct ice_tx_buf *first;
2297	struct ethhdr *eth;
2298	unsigned int count;
2299	int tso, csum;
2300
2301	ice_trace(xmit_frame_ring, tx_ring, skb);
2302
2303	count = ice_xmit_desc_count(skb);
2304	if (ice_chk_linearize(skb, count)) {
2305		if (__skb_linearize(skb))
2306			goto out_drop;
2307		count = ice_txd_use_count(skb->len);
2308		tx_ring->ring_stats->tx_stats.tx_linearize++;
2309	}
2310
2311	/* need: 1 descriptor per page * PAGE_SIZE/ICE_MAX_DATA_PER_TXD,
2312	 *       + 1 desc for skb_head_len/ICE_MAX_DATA_PER_TXD,
2313	 *       + 4 desc gap to avoid the cache line where head is,
2314	 *       + 1 desc for context descriptor,
2315	 * otherwise try next time
2316	 */
2317	if (ice_maybe_stop_tx(tx_ring, count + ICE_DESCS_PER_CACHE_LINE +
2318			      ICE_DESCS_FOR_CTX_DESC)) {
2319		tx_ring->ring_stats->tx_stats.tx_busy++;
2320		return NETDEV_TX_BUSY;
2321	}
2322
2323	/* prefetch for bql data which is infrequently used */
2324	netdev_txq_bql_enqueue_prefetchw(txring_txq(tx_ring));
2325
2326	offload.tx_ring = tx_ring;
2327
2328	/* record the location of the first descriptor for this packet */
2329	first = &tx_ring->tx_buf[tx_ring->next_to_use];
2330	first->skb = skb;
2331	first->bytecount = max_t(unsigned int, skb->len, ETH_ZLEN);
2332	first->gso_segs = 1;
2333	first->tx_flags = 0;
2334
2335	/* prepare the VLAN tagging flags for Tx */
2336	ice_tx_prepare_vlan_flags(tx_ring, first);
2337	if (first->tx_flags & ICE_TX_FLAGS_HW_OUTER_SINGLE_VLAN) {
2338		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2339					(ICE_TX_CTX_DESC_IL2TAG2 <<
2340					ICE_TXD_CTX_QW1_CMD_S));
2341		offload.cd_l2tag2 = (first->tx_flags & ICE_TX_FLAGS_VLAN_M) >>
2342			ICE_TX_FLAGS_VLAN_S;
2343	}
2344
2345	/* set up TSO offload */
2346	tso = ice_tso(first, &offload);
2347	if (tso < 0)
2348		goto out_drop;
2349
2350	/* always set up Tx checksum offload */
2351	csum = ice_tx_csum(first, &offload);
2352	if (csum < 0)
2353		goto out_drop;
2354
2355	/* allow CONTROL frames egress from main VSI if FW LLDP disabled */
2356	eth = (struct ethhdr *)skb_mac_header(skb);
2357	if (unlikely((skb->priority == TC_PRIO_CONTROL ||
2358		      eth->h_proto == htons(ETH_P_LLDP)) &&
2359		     vsi->type == ICE_VSI_PF &&
2360		     vsi->port_info->qos_cfg.is_sw_lldp))
2361		offload.cd_qw1 |= (u64)(ICE_TX_DESC_DTYPE_CTX |
2362					ICE_TX_CTX_DESC_SWTCH_UPLINK <<
2363					ICE_TXD_CTX_QW1_CMD_S);
2364
2365	ice_tstamp(tx_ring, skb, first, &offload);
2366	if (ice_is_switchdev_running(vsi->back))
2367		ice_eswitch_set_target_vsi(skb, &offload);
2368
2369	if (offload.cd_qw1 & ICE_TX_DESC_DTYPE_CTX) {
2370		struct ice_tx_ctx_desc *cdesc;
2371		u16 i = tx_ring->next_to_use;
2372
2373		/* grab the next descriptor */
2374		cdesc = ICE_TX_CTX_DESC(tx_ring, i);
2375		i++;
2376		tx_ring->next_to_use = (i < tx_ring->count) ? i : 0;
2377
2378		/* setup context descriptor */
2379		cdesc->tunneling_params = cpu_to_le32(offload.cd_tunnel_params);
2380		cdesc->l2tag2 = cpu_to_le16(offload.cd_l2tag2);
2381		cdesc->rsvd = cpu_to_le16(0);
2382		cdesc->qw1 = cpu_to_le64(offload.cd_qw1);
2383	}
2384
2385	ice_tx_map(tx_ring, first, &offload);
2386	return NETDEV_TX_OK;
2387
2388out_drop:
2389	ice_trace(xmit_frame_ring_drop, tx_ring, skb);
2390	dev_kfree_skb_any(skb);
2391	return NETDEV_TX_OK;
2392}
2393
2394/**
2395 * ice_start_xmit - Selects the correct VSI and Tx queue to send buffer
2396 * @skb: send buffer
2397 * @netdev: network interface device structure
2398 *
2399 * Returns NETDEV_TX_OK if sent, else an error code
2400 */
2401netdev_tx_t ice_start_xmit(struct sk_buff *skb, struct net_device *netdev)
2402{
2403	struct ice_netdev_priv *np = netdev_priv(netdev);
2404	struct ice_vsi *vsi = np->vsi;
2405	struct ice_tx_ring *tx_ring;
2406
2407	tx_ring = vsi->tx_rings[skb->queue_mapping];
2408
2409	/* hardware can't handle really short frames, hardware padding works
2410	 * beyond this point
2411	 */
2412	if (skb_put_padto(skb, ICE_MIN_TX_LEN))
2413		return NETDEV_TX_OK;
2414
2415	return ice_xmit_frame_ring(skb, tx_ring);
2416}
2417
2418/**
2419 * ice_get_dscp_up - return the UP/TC value for a SKB
2420 * @dcbcfg: DCB config that contains DSCP to UP/TC mapping
2421 * @skb: SKB to query for info to determine UP/TC
2422 *
2423 * This function is to only be called when the PF is in L3 DSCP PFC mode
2424 */
2425static u8 ice_get_dscp_up(struct ice_dcbx_cfg *dcbcfg, struct sk_buff *skb)
2426{
2427	u8 dscp = 0;
2428
2429	if (skb->protocol == htons(ETH_P_IP))
2430		dscp = ipv4_get_dsfield(ip_hdr(skb)) >> 2;
2431	else if (skb->protocol == htons(ETH_P_IPV6))
2432		dscp = ipv6_get_dsfield(ipv6_hdr(skb)) >> 2;
2433
2434	return dcbcfg->dscp_map[dscp];
2435}
2436
2437u16
2438ice_select_queue(struct net_device *netdev, struct sk_buff *skb,
2439		 struct net_device *sb_dev)
2440{
2441	struct ice_pf *pf = ice_netdev_to_pf(netdev);
2442	struct ice_dcbx_cfg *dcbcfg;
2443
2444	dcbcfg = &pf->hw.port_info->qos_cfg.local_dcbx_cfg;
2445	if (dcbcfg->pfc_mode == ICE_QOS_MODE_DSCP)
2446		skb->priority = ice_get_dscp_up(dcbcfg, skb);
2447
2448	return netdev_pick_tx(netdev, skb, sb_dev);
2449}
2450
2451/**
2452 * ice_clean_ctrl_tx_irq - interrupt handler for flow director Tx queue
2453 * @tx_ring: tx_ring to clean
2454 */
2455void ice_clean_ctrl_tx_irq(struct ice_tx_ring *tx_ring)
2456{
2457	struct ice_vsi *vsi = tx_ring->vsi;
2458	s16 i = tx_ring->next_to_clean;
2459	int budget = ICE_DFLT_IRQ_WORK;
2460	struct ice_tx_desc *tx_desc;
2461	struct ice_tx_buf *tx_buf;
2462
2463	tx_buf = &tx_ring->tx_buf[i];
2464	tx_desc = ICE_TX_DESC(tx_ring, i);
2465	i -= tx_ring->count;
2466
2467	do {
2468		struct ice_tx_desc *eop_desc = tx_buf->next_to_watch;
2469
2470		/* if next_to_watch is not set then there is no pending work */
2471		if (!eop_desc)
2472			break;
2473
2474		/* prevent any other reads prior to eop_desc */
2475		smp_rmb();
2476
2477		/* if the descriptor isn't done, no work to do */
2478		if (!(eop_desc->cmd_type_offset_bsz &
2479		      cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)))
2480			break;
2481
2482		/* clear next_to_watch to prevent false hangs */
2483		tx_buf->next_to_watch = NULL;
2484		tx_desc->buf_addr = 0;
2485		tx_desc->cmd_type_offset_bsz = 0;
2486
2487		/* move past filter desc */
2488		tx_buf++;
2489		tx_desc++;
2490		i++;
2491		if (unlikely(!i)) {
2492			i -= tx_ring->count;
2493			tx_buf = tx_ring->tx_buf;
2494			tx_desc = ICE_TX_DESC(tx_ring, 0);
2495		}
2496
2497		/* unmap the data header */
2498		if (dma_unmap_len(tx_buf, len))
2499			dma_unmap_single(tx_ring->dev,
2500					 dma_unmap_addr(tx_buf, dma),
2501					 dma_unmap_len(tx_buf, len),
2502					 DMA_TO_DEVICE);
2503		if (tx_buf->tx_flags & ICE_TX_FLAGS_DUMMY_PKT)
2504			devm_kfree(tx_ring->dev, tx_buf->raw_buf);
2505
2506		/* clear next_to_watch to prevent false hangs */
2507		tx_buf->raw_buf = NULL;
2508		tx_buf->tx_flags = 0;
2509		tx_buf->next_to_watch = NULL;
2510		dma_unmap_len_set(tx_buf, len, 0);
2511		tx_desc->buf_addr = 0;
2512		tx_desc->cmd_type_offset_bsz = 0;
2513
2514		/* move past eop_desc for start of next FD desc */
2515		tx_buf++;
2516		tx_desc++;
2517		i++;
2518		if (unlikely(!i)) {
2519			i -= tx_ring->count;
2520			tx_buf = tx_ring->tx_buf;
2521			tx_desc = ICE_TX_DESC(tx_ring, 0);
2522		}
2523
2524		budget--;
2525	} while (likely(budget));
2526
2527	i += tx_ring->count;
2528	tx_ring->next_to_clean = i;
2529
2530	/* re-enable interrupt if needed */
2531	ice_irq_dynamic_ena(&vsi->back->hw, vsi, vsi->q_vectors[0]);
2532}