drivers/net/ethernet/intel/ice/ice_txrx_lib.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /* Copyright (c) 2019, Intel Corporation. */
   3
   4 #include <linux/filter.h>
   5 #include <linux/net/intel/libie/rx.h>
   6
   7 #include "ice_txrx_lib.h"
   8 #include "ice_eswitch.h"
   9 #include "ice_lib.h"
  10
  11 /**
  12  * ice_release_rx_desc - Store the new tail and head values
  13  * @rx_ring: ring to bump
  14  * @val: new head index
  15  */
  16 void ice_release_rx_desc(struct ice_rx_ring *rx_ring, u16 val)
  17 {
  18         u16 prev_ntu = rx_ring->next_to_use & ~0x7;
  19
  20         rx_ring->next_to_use = val;
  21
  22         /* update next to alloc since we have filled the ring */
  23         rx_ring->next_to_alloc = val;
  24
  25         /* QRX_TAIL will be updated with any tail value, but hardware ignores
  26          * the lower 3 bits. This makes it so we only bump tail on meaningful
  27          * boundaries. Also, this allows us to bump tail on intervals of 8 up to
  28          * the budget depending on the current traffic load.
  29          */
  30         val &= ~0x7;
  31         if (prev_ntu != val) {
  32                 /* Force memory writes to complete before letting h/w
  33                  * know there are new descriptors to fetch. (Only
  34                  * applicable for weak-ordered memory model archs,
  35                  * such as IA-64).
  36                  */
  37                 wmb();
  38                 writel(val, rx_ring->tail);
  39         }
  40 }
  41
  42 /**
  43  * ice_get_rx_hash - get RX hash value from descriptor
  44  * @rx_desc: specific descriptor
  45  *
  46  * Returns hash, if present, 0 otherwise.
  47  */
  48 static u32 ice_get_rx_hash(const union ice_32b_rx_flex_desc *rx_desc)
  49 {
  50         const struct ice_32b_rx_flex_desc_nic *nic_mdid;
  51
  52         if (unlikely(rx_desc->wb.rxdid != ICE_RXDID_FLEX_NIC))
  53                 return 0;
  54
  55         nic_mdid = (struct ice_32b_rx_flex_desc_nic *)rx_desc;
  56         return le32_to_cpu(nic_mdid->rss_hash);
  57 }
  58
  59 /**
  60  * ice_rx_hash_to_skb - set the hash value in the skb
  61  * @rx_ring: descriptor ring
  62  * @rx_desc: specific descriptor
  63  * @skb: pointer to current skb
  64  * @rx_ptype: the ptype value from the descriptor
  65  */
  66 static void
  67 ice_rx_hash_to_skb(const struct ice_rx_ring *rx_ring,
  68                    const union ice_32b_rx_flex_desc *rx_desc,
  69                    struct sk_buff *skb, u16 rx_ptype)
  70 {
  71         struct libeth_rx_pt decoded;
  72         u32 hash;
  73
  74         decoded = libie_rx_pt_parse(rx_ptype);
  75         if (!libeth_rx_pt_has_hash(rx_ring->netdev, decoded))
  76                 return;
  77
  78         hash = ice_get_rx_hash(rx_desc);
  79         if (likely(hash))
  80                 libeth_rx_pt_set_hash(skb, hash, decoded);
  81 }
  82
  83 /**
  84  * ice_rx_csum - Indicate in skb if checksum is good
  85  * @ring: the ring we care about
  86  * @skb: skb currently being received and modified
  87  * @rx_desc: the receive descriptor
  88  * @ptype: the packet type decoded by hardware
  89  *
  90  * skb->protocol must be set before this function is called
  91  */
  92 static void
  93 ice_rx_csum(struct ice_rx_ring *ring, struct sk_buff *skb,
  94             union ice_32b_rx_flex_desc *rx_desc, u16 ptype)
  95 {
  96         struct libeth_rx_pt decoded;
  97         u16 rx_status0, rx_status1;
  98         bool ipv4, ipv6;
  99
 100         /* Start with CHECKSUM_NONE and by default csum_level = 0 */
 101         skb->ip_summed = CHECKSUM_NONE;
 102
 103         decoded = libie_rx_pt_parse(ptype);
 104         if (!libeth_rx_pt_has_checksum(ring->netdev, decoded))
 105                 return;
 106
 107         rx_status0 = le16_to_cpu(rx_desc->wb.status_error0);
 108         rx_status1 = le16_to_cpu(rx_desc->wb.status_error1);
 109
 110         /* check if HW has decoded the packet and checksum */
 111         if (!(rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_L3L4P_S)))
 112                 return;
 113
 114         ipv4 = libeth_rx_pt_get_ip_ver(decoded) == LIBETH_RX_PT_OUTER_IPV4;
 115         ipv6 = libeth_rx_pt_get_ip_ver(decoded) == LIBETH_RX_PT_OUTER_IPV6;
 116
 117         if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EIPE_S)))) {
 118                 ring->vsi->back->hw_rx_eipe_error++;
 119                 return;
 120         }
 121
 122         if (ipv4 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_IPE_S))))
 123                 goto checksum_fail;
 124
 125         if (ipv6 && (rx_status0 & (BIT(ICE_RX_FLEX_DESC_STATUS0_IPV6EXADD_S))))
 126                 goto checksum_fail;
 127
 128         /* check for L4 errors and handle packets that were not able to be
 129          * checksummed due to arrival speed
 130          */
 131         if (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_L4E_S))
 132                 goto checksum_fail;
 133
 134         /* check for outer UDP checksum error in tunneled packets */
 135         if ((rx_status1 & BIT(ICE_RX_FLEX_DESC_STATUS1_NAT_S)) &&
 136             (rx_status0 & BIT(ICE_RX_FLEX_DESC_STATUS0_XSUM_EUDPE_S)))
 137                 goto checksum_fail;
 138
 139         /* If there is an outer header present that might contain a checksum
 140          * we need to bump the checksum level by 1 to reflect the fact that
 141          * we are indicating we validated the inner checksum.
 142          */
 143         if (decoded.tunnel_type >= LIBETH_RX_PT_TUNNEL_IP_GRENAT)
 144                 skb->csum_level = 1;
 145
 146         skb->ip_summed = CHECKSUM_UNNECESSARY;
 147         return;
 148
 149 checksum_fail:
 150         ring->vsi->back->hw_csum_rx_error++;
 151 }
 152
 153 /**
 154  * ice_ptp_rx_hwts_to_skb - Put RX timestamp into skb
 155  * @rx_ring: Ring to get the VSI info
 156  * @rx_desc: Receive descriptor
 157  * @skb: Particular skb to send timestamp with
 158  *
 159  * The timestamp is in ns, so we must convert the result first.
 160  */
 161 static void
 162 ice_ptp_rx_hwts_to_skb(struct ice_rx_ring *rx_ring,
 163                        const union ice_32b_rx_flex_desc *rx_desc,
 164                        struct sk_buff *skb)
 165 {
 166         u64 ts_ns = ice_ptp_get_rx_hwts(rx_desc, &rx_ring->pkt_ctx);
 167
 168         skb_hwtstamps(skb)->hwtstamp = ns_to_ktime(ts_ns);
 169 }
 170
 171 /**
 172  * ice_get_ptype - Read HW packet type from the descriptor
 173  * @rx_desc: RX descriptor
 174  */
 175 static u16 ice_get_ptype(const union ice_32b_rx_flex_desc *rx_desc)
 176 {
 177         return le16_to_cpu(rx_desc->wb.ptype_flex_flags0) &
 178                ICE_RX_FLEX_DESC_PTYPE_M;
 179 }
 180
 181 /**
 182  * ice_process_skb_fields - Populate skb header fields from Rx descriptor
 183  * @rx_ring: Rx descriptor ring packet is being transacted on
 184  * @rx_desc: pointer to the EOP Rx descriptor
 185  * @skb: pointer to current skb being populated
 186  *
 187  * This function checks the ring, descriptor, and packet information in
 188  * order to populate the hash, checksum, VLAN, protocol, and
 189  * other fields within the skb.
 190  */
 191 void
 192 ice_process_skb_fields(struct ice_rx_ring *rx_ring,
 193                        union ice_32b_rx_flex_desc *rx_desc,
 194                        struct sk_buff *skb)
 195 {
 196         u16 ptype = ice_get_ptype(rx_desc);
 197
 198         ice_rx_hash_to_skb(rx_ring, rx_desc, skb, ptype);
 199
 200         /* modifies the skb - consumes the enet header */
 201         if (unlikely(rx_ring->flags & ICE_RX_FLAGS_MULTIDEV)) {
 202                 struct net_device *netdev = ice_eswitch_get_target(rx_ring,
 203                                                                    rx_desc);
 204
 205                 if (ice_is_port_repr_netdev(netdev))
 206                         ice_repr_inc_rx_stats(netdev, skb->len);
 207                 skb->protocol = eth_type_trans(skb, netdev);
 208         } else {
 209                 skb->protocol = eth_type_trans(skb, rx_ring->netdev);
 210         }
 211
 212         ice_rx_csum(rx_ring, skb, rx_desc, ptype);
 213
 214         if (rx_ring->ptp_rx)
 215                 ice_ptp_rx_hwts_to_skb(rx_ring, rx_desc, skb);
 216 }
 217
 218 /**
 219  * ice_receive_skb - Send a completed packet up the stack
 220  * @rx_ring: Rx ring in play
 221  * @skb: packet to send up
 222  * @vlan_tci: VLAN TCI for packet
 223  *
 224  * This function sends the completed packet (via. skb) up the stack using
 225  * gro receive functions (with/without VLAN tag)
 226  */
 227 void
 228 ice_receive_skb(struct ice_rx_ring *rx_ring, struct sk_buff *skb, u16 vlan_tci)
 229 {
 230         if ((vlan_tci & VLAN_VID_MASK) && rx_ring->vlan_proto)
 231                 __vlan_hwaccel_put_tag(skb, rx_ring->vlan_proto,
 232                                        vlan_tci);
 233
 234         napi_gro_receive(&rx_ring->q_vector->napi, skb);
 235 }
 236
 237 /**
 238  * ice_clean_xdp_tx_buf - Free and unmap XDP Tx buffer
 239  * @dev: device for DMA mapping
 240  * @tx_buf: Tx buffer to clean
 241  * @bq: XDP bulk flush struct
 242  */
 243 static void
 244 ice_clean_xdp_tx_buf(struct device *dev, struct ice_tx_buf *tx_buf,
 245                      struct xdp_frame_bulk *bq)
 246 {
 247         dma_unmap_single(dev, dma_unmap_addr(tx_buf, dma),
 248                          dma_unmap_len(tx_buf, len), DMA_TO_DEVICE);
 249         dma_unmap_len_set(tx_buf, len, 0);
 250
 251         switch (tx_buf->type) {
 252         case ICE_TX_BUF_XDP_TX:
 253                 page_frag_free(tx_buf->raw_buf);
 254                 break;
 255         case ICE_TX_BUF_XDP_XMIT:
 256                 xdp_return_frame_bulk(tx_buf->xdpf, bq);
 257                 break;
 258         }
 259
 260         tx_buf->type = ICE_TX_BUF_EMPTY;
 261 }
 262
 263 /**
 264  * ice_clean_xdp_irq - Reclaim resources after transmit completes on XDP ring
 265  * @xdp_ring: XDP ring to clean
 266  */
 267 static u32 ice_clean_xdp_irq(struct ice_tx_ring *xdp_ring)
 268 {
 269         int total_bytes = 0, total_pkts = 0;
 270         struct device *dev = xdp_ring->dev;
 271         u32 ntc = xdp_ring->next_to_clean;
 272         struct ice_tx_desc *tx_desc;
 273         u32 cnt = xdp_ring->count;
 274         struct xdp_frame_bulk bq;
 275         u32 frags, xdp_tx = 0;
 276         u32 ready_frames = 0;
 277         u32 idx;
 278         u32 ret;
 279
 280         idx = xdp_ring->tx_buf[ntc].rs_idx;
 281         tx_desc = ICE_TX_DESC(xdp_ring, idx);
 282         if (tx_desc->cmd_type_offset_bsz &
 283             cpu_to_le64(ICE_TX_DESC_DTYPE_DESC_DONE)) {
 284                 if (idx >= ntc)
 285                         ready_frames = idx - ntc + 1;
 286                 else
 287                         ready_frames = idx + cnt - ntc + 1;
 288         }
 289
 290         if (unlikely(!ready_frames))
 291                 return 0;
 292         ret = ready_frames;
 293
 294         xdp_frame_bulk_init(&bq);
 295         rcu_read_lock(); /* xdp_return_frame_bulk() */
 296
 297         while (ready_frames) {
 298                 struct ice_tx_buf *tx_buf = &xdp_ring->tx_buf[ntc];
 299                 struct ice_tx_buf *head = tx_buf;
 300
 301                 /* bytecount holds size of head + frags */
 302                 total_bytes += tx_buf->bytecount;
 303                 frags = tx_buf->nr_frags;
 304                 total_pkts++;
 305                 /* count head + frags */
 306                 ready_frames -= frags + 1;
 307                 xdp_tx++;
 308
 309                 ntc++;
 310                 if (ntc == cnt)
 311                         ntc = 0;
 312
 313                 for (int i = 0; i < frags; i++) {
 314                         tx_buf = &xdp_ring->tx_buf[ntc];
 315
 316                         ice_clean_xdp_tx_buf(dev, tx_buf, &bq);
 317                         ntc++;
 318                         if (ntc == cnt)
 319                                 ntc = 0;
 320                 }
 321
 322                 ice_clean_xdp_tx_buf(dev, head, &bq);
 323         }
 324
 325         xdp_flush_frame_bulk(&bq);
 326         rcu_read_unlock();
 327
 328         tx_desc->cmd_type_offset_bsz = 0;
 329         xdp_ring->next_to_clean = ntc;
 330         xdp_ring->xdp_tx_active -= xdp_tx;
 331         ice_update_tx_ring_stats(xdp_ring, total_pkts, total_bytes);
 332
 333         return ret;
 334 }
 335
 336 /**
 337  * __ice_xmit_xdp_ring - submit frame to XDP ring for transmission
 338  * @xdp: XDP buffer to be placed onto Tx descriptors
 339  * @xdp_ring: XDP ring for transmission
 340  * @frame: whether this comes from .ndo_xdp_xmit()
 341  */
 342 int __ice_xmit_xdp_ring(struct xdp_buff *xdp, struct ice_tx_ring *xdp_ring,
 343                         bool frame)
 344 {
 345         struct skb_shared_info *sinfo = NULL;
 346         u32 size = xdp->data_end - xdp->data;
 347         struct device *dev = xdp_ring->dev;
 348         u32 ntu = xdp_ring->next_to_use;
 349         struct ice_tx_desc *tx_desc;
 350         struct ice_tx_buf *tx_head;
 351         struct ice_tx_buf *tx_buf;
 352         u32 cnt = xdp_ring->count;
 353         void *data = xdp->data;
 354         u32 nr_frags = 0;
 355         u32 free_space;
 356         u32 frag = 0;
 357
 358         free_space = ICE_DESC_UNUSED(xdp_ring);
 359         if (free_space < ICE_RING_QUARTER(xdp_ring))
 360                 free_space += ice_clean_xdp_irq(xdp_ring);
 361
 362         if (unlikely(!free_space))
 363                 goto busy;
 364
 365         if (unlikely(xdp_buff_has_frags(xdp))) {
 366                 sinfo = xdp_get_shared_info_from_buff(xdp);
 367                 nr_frags = sinfo->nr_frags;
 368                 if (free_space < nr_frags + 1)
 369                         goto busy;
 370         }
 371
 372         tx_desc = ICE_TX_DESC(xdp_ring, ntu);
 373         tx_head = &xdp_ring->tx_buf[ntu];
 374         tx_buf = tx_head;
 375
 376         for (;;) {
 377                 dma_addr_t dma;
 378
 379                 dma = dma_map_single(dev, data, size, DMA_TO_DEVICE);
 380                 if (dma_mapping_error(dev, dma))
 381                         goto dma_unmap;
 382
 383                 /* record length, and DMA address */
 384                 dma_unmap_len_set(tx_buf, len, size);
 385                 dma_unmap_addr_set(tx_buf, dma, dma);
 386
 387                 if (frame) {
 388                         tx_buf->type = ICE_TX_BUF_FRAG;
 389                 } else {
 390                         tx_buf->type = ICE_TX_BUF_XDP_TX;
 391                         tx_buf->raw_buf = data;
 392                 }
 393
 394                 tx_desc->buf_addr = cpu_to_le64(dma);
 395                 tx_desc->cmd_type_offset_bsz = ice_build_ctob(0, 0, size, 0);
 396
 397                 ntu++;
 398                 if (ntu == cnt)
 399                         ntu = 0;
 400
 401                 if (frag == nr_frags)
 402                         break;
 403
 404                 tx_desc = ICE_TX_DESC(xdp_ring, ntu);
 405                 tx_buf = &xdp_ring->tx_buf[ntu];
 406
 407                 data = skb_frag_address(&sinfo->frags[frag]);
 408                 size = skb_frag_size(&sinfo->frags[frag]);
 409                 frag++;
 410         }
 411
 412         /* store info about bytecount and frag count in first desc */
 413         tx_head->bytecount = xdp_get_buff_len(xdp);
 414         tx_head->nr_frags = nr_frags;
 415
 416         if (frame) {
 417                 tx_head->type = ICE_TX_BUF_XDP_XMIT;
 418                 tx_head->xdpf = xdp->data_hard_start;
 419         }
 420
 421         /* update last descriptor from a frame with EOP */
 422         tx_desc->cmd_type_offset_bsz |=
 423                 cpu_to_le64(ICE_TX_DESC_CMD_EOP << ICE_TXD_QW1_CMD_S);
 424
 425         xdp_ring->xdp_tx_active++;
 426         xdp_ring->next_to_use = ntu;
 427
 428         return ICE_XDP_TX;
 429
 430 dma_unmap:
 431         for (;;) {
 432                 tx_buf = &xdp_ring->tx_buf[ntu];
 433                 dma_unmap_page(dev, dma_unmap_addr(tx_buf, dma),
 434                                dma_unmap_len(tx_buf, len), DMA_TO_DEVICE);
 435                 dma_unmap_len_set(tx_buf, len, 0);
 436                 if (tx_buf == tx_head)
 437                         break;
 438
 439                 if (!ntu)
 440                         ntu += cnt;
 441                 ntu--;
 442         }
 443         return ICE_XDP_CONSUMED;
 444
 445 busy:
 446         xdp_ring->ring_stats->tx_stats.tx_busy++;
 447
 448         return ICE_XDP_CONSUMED;
 449 }
 450
 451 /**
 452  * ice_finalize_xdp_rx - Bump XDP Tx tail and/or flush redirect map
 453  * @xdp_ring: XDP ring
 454  * @xdp_res: Result of the receive batch
 455  * @first_idx: index to write from caller
 456  *
 457  * This function bumps XDP Tx tail and/or flush redirect map, and
 458  * should be called when a batch of packets has been processed in the
 459  * napi loop.
 460  */
 461 void ice_finalize_xdp_rx(struct ice_tx_ring *xdp_ring, unsigned int xdp_res,
 462                          u32 first_idx)
 463 {
 464         struct ice_tx_buf *tx_buf = &xdp_ring->tx_buf[first_idx];
 465
 466         if (xdp_res & ICE_XDP_REDIR)
 467                 xdp_do_flush();
 468
 469         if (xdp_res & ICE_XDP_TX) {
 470                 if (static_branch_unlikely(&ice_xdp_locking_key))
 471                         spin_lock(&xdp_ring->tx_lock);
 472                 /* store index of descriptor with RS bit set in the first
 473                  * ice_tx_buf of given NAPI batch
 474                  */
 475                 tx_buf->rs_idx = ice_set_rs_bit(xdp_ring);
 476                 ice_xdp_ring_update_tail(xdp_ring);
 477                 if (static_branch_unlikely(&ice_xdp_locking_key))
 478                         spin_unlock(&xdp_ring->tx_lock);
 479         }
 480 }
 481
 482 /**
 483  * ice_xdp_rx_hw_ts - HW timestamp XDP hint handler
 484  * @ctx: XDP buff pointer
 485  * @ts_ns: destination address
 486  *
 487  * Copy HW timestamp (if available) to the destination address.
 488  */
 489 static int ice_xdp_rx_hw_ts(const struct xdp_md *ctx, u64 *ts_ns)
 490 {
 491         const struct ice_xdp_buff *xdp_ext = (void *)ctx;
 492
 493         *ts_ns = ice_ptp_get_rx_hwts(xdp_ext->eop_desc,
 494                                      xdp_ext->pkt_ctx);
 495         if (!*ts_ns)
 496                 return -ENODATA;
 497
 498         return 0;
 499 }
 500
 501 /**
 502  * ice_xdp_rx_hash_type - Get XDP-specific hash type from the RX descriptor
 503  * @eop_desc: End of Packet descriptor
 504  */
 505 static enum xdp_rss_hash_type
 506 ice_xdp_rx_hash_type(const union ice_32b_rx_flex_desc *eop_desc)
 507 {
 508         return libie_rx_pt_parse(ice_get_ptype(eop_desc)).hash_type;
 509 }
 510
 511 /**
 512  * ice_xdp_rx_hash - RX hash XDP hint handler
 513  * @ctx: XDP buff pointer
 514  * @hash: hash destination address
 515  * @rss_type: XDP hash type destination address
 516  *
 517  * Copy RX hash (if available) and its type to the destination address.
 518  */
 519 static int ice_xdp_rx_hash(const struct xdp_md *ctx, u32 *hash,
 520                            enum xdp_rss_hash_type *rss_type)
 521 {
 522         const struct ice_xdp_buff *xdp_ext = (void *)ctx;
 523
 524         *hash = ice_get_rx_hash(xdp_ext->eop_desc);
 525         *rss_type = ice_xdp_rx_hash_type(xdp_ext->eop_desc);
 526         if (!likely(*hash))
 527                 return -ENODATA;
 528
 529         return 0;
 530 }
 531
 532 /**
 533  * ice_xdp_rx_vlan_tag - VLAN tag XDP hint handler
 534  * @ctx: XDP buff pointer
 535  * @vlan_proto: destination address for VLAN protocol
 536  * @vlan_tci: destination address for VLAN TCI
 537  *
 538  * Copy VLAN tag (if was stripped) and corresponding protocol
 539  * to the destination address.
 540  */
 541 static int ice_xdp_rx_vlan_tag(const struct xdp_md *ctx, __be16 *vlan_proto,
 542                                u16 *vlan_tci)
 543 {
 544         const struct ice_xdp_buff *xdp_ext = (void *)ctx;
 545
 546         *vlan_proto = xdp_ext->pkt_ctx->vlan_proto;
 547         if (!*vlan_proto)
 548                 return -ENODATA;
 549
 550         *vlan_tci = ice_get_vlan_tci(xdp_ext->eop_desc);
 551         if (!*vlan_tci)
 552                 return -ENODATA;
 553
 554         return 0;
 555 }
 556
 557 const struct xdp_metadata_ops ice_xdp_md_ops = {
 558         .xmo_rx_timestamp               = ice_xdp_rx_hw_ts,
 559         .xmo_rx_hash                    = ice_xdp_rx_hash,
 560         .xmo_rx_vlan_tag                = ice_xdp_rx_vlan_tag,
 561 };