1 /* Broadcom NetXtreme-C/E network driver. 2 * 3 * Copyright (c) 2016-2017 Broadcom Limited 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation. 8 */ 9 #include <linux/kernel.h> 10 #include <linux/errno.h> 11 #include <linux/pci.h> 12 #include <linux/netdevice.h> 13 #include <linux/etherdevice.h> 14 #include <linux/if_vlan.h> 15 #include <linux/bpf.h> 16 #include <linux/bpf_trace.h> 17 #include <linux/filter.h> 18 #include <net/page_pool.h> 19 #include "bnxt_hsi.h" 20 #include "bnxt.h" 21 #include "bnxt_xdp.h" 22 23 DEFINE_STATIC_KEY_FALSE(bnxt_xdp_locking_key); 24 25 struct bnxt_sw_tx_bd *bnxt_xmit_bd(struct bnxt *bp, 26 struct bnxt_tx_ring_info *txr, 27 dma_addr_t mapping, u32 len, 28 struct xdp_buff *xdp) 29 { 30 struct skb_shared_info *sinfo; 31 struct bnxt_sw_tx_bd *tx_buf; 32 struct tx_bd *txbd; 33 int num_frags = 0; 34 u32 flags; 35 u16 prod; 36 int i; 37 38 if (xdp && xdp_buff_has_frags(xdp)) { 39 sinfo = xdp_get_shared_info_from_buff(xdp); 40 num_frags = sinfo->nr_frags; 41 } 42 43 /* fill up the first buffer */ 44 prod = txr->tx_prod; 45 tx_buf = &txr->tx_buf_ring[prod]; 46 tx_buf->nr_frags = num_frags; 47 if (xdp) 48 tx_buf->page = virt_to_head_page(xdp->data); 49 50 txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)]; 51 flags = (len << TX_BD_LEN_SHIFT) | 52 ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT) | 53 bnxt_lhint_arr[len >> 9]; 54 txbd->tx_bd_len_flags_type = cpu_to_le32(flags); 55 txbd->tx_bd_opaque = prod; 56 txbd->tx_bd_haddr = cpu_to_le64(mapping); 57 58 /* now let us fill up the frags into the next buffers */ 59 for (i = 0; i < num_frags ; i++) { 60 skb_frag_t *frag = &sinfo->frags[i]; 61 struct bnxt_sw_tx_bd *frag_tx_buf; 62 struct pci_dev *pdev = bp->pdev; 63 dma_addr_t frag_mapping; 64 int frag_len; 65 66 prod = NEXT_TX(prod); 67 txr->tx_prod = prod; 68 69 /* first fill up the first buffer */ 70 frag_tx_buf = &txr->tx_buf_ring[prod]; 71 frag_tx_buf->page = skb_frag_page(frag); 72 73 txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)]; 74 75 frag_len = skb_frag_size(frag); 76 frag_mapping = skb_frag_dma_map(&pdev->dev, frag, 0, 77 frag_len, DMA_TO_DEVICE); 78 79 if (unlikely(dma_mapping_error(&pdev->dev, frag_mapping))) 80 return NULL; 81 82 dma_unmap_addr_set(frag_tx_buf, mapping, frag_mapping); 83 84 flags = frag_len << TX_BD_LEN_SHIFT; 85 txbd->tx_bd_len_flags_type = cpu_to_le32(flags); 86 txbd->tx_bd_haddr = cpu_to_le64(frag_mapping); 87 88 len = frag_len; 89 } 90 91 flags &= ~TX_BD_LEN; 92 txbd->tx_bd_len_flags_type = cpu_to_le32(((len) << TX_BD_LEN_SHIFT) | flags | 93 TX_BD_FLAGS_PACKET_END); 94 /* Sync TX BD */ 95 wmb(); 96 prod = NEXT_TX(prod); 97 txr->tx_prod = prod; 98 99 return tx_buf; 100 } 101 102 static void __bnxt_xmit_xdp(struct bnxt *bp, struct bnxt_tx_ring_info *txr, 103 dma_addr_t mapping, u32 len, u16 rx_prod, 104 struct xdp_buff *xdp) 105 { 106 struct bnxt_sw_tx_bd *tx_buf; 107 108 tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, xdp); 109 tx_buf->rx_prod = rx_prod; 110 tx_buf->action = XDP_TX; 111 112 } 113 114 static void __bnxt_xmit_xdp_redirect(struct bnxt *bp, 115 struct bnxt_tx_ring_info *txr, 116 dma_addr_t mapping, u32 len, 117 struct xdp_frame *xdpf) 118 { 119 struct bnxt_sw_tx_bd *tx_buf; 120 121 tx_buf = bnxt_xmit_bd(bp, txr, mapping, len, NULL); 122 tx_buf->action = XDP_REDIRECT; 123 tx_buf->xdpf = xdpf; 124 dma_unmap_addr_set(tx_buf, mapping, mapping); 125 dma_unmap_len_set(tx_buf, len, 0); 126 } 127 128 void bnxt_tx_int_xdp(struct bnxt *bp, struct bnxt_napi *bnapi, int nr_pkts) 129 { 130 struct bnxt_tx_ring_info *txr = bnapi->tx_ring; 131 struct bnxt_rx_ring_info *rxr = bnapi->rx_ring; 132 bool rx_doorbell_needed = false; 133 struct bnxt_sw_tx_bd *tx_buf; 134 u16 tx_cons = txr->tx_cons; 135 u16 last_tx_cons = tx_cons; 136 int i, j, frags; 137 138 for (i = 0; i < nr_pkts; i++) { 139 tx_buf = &txr->tx_buf_ring[tx_cons]; 140 141 if (tx_buf->action == XDP_REDIRECT) { 142 struct pci_dev *pdev = bp->pdev; 143 144 dma_unmap_single(&pdev->dev, 145 dma_unmap_addr(tx_buf, mapping), 146 dma_unmap_len(tx_buf, len), 147 DMA_TO_DEVICE); 148 xdp_return_frame(tx_buf->xdpf); 149 tx_buf->action = 0; 150 tx_buf->xdpf = NULL; 151 } else if (tx_buf->action == XDP_TX) { 152 rx_doorbell_needed = true; 153 last_tx_cons = tx_cons; 154 155 frags = tx_buf->nr_frags; 156 for (j = 0; j < frags; j++) { 157 tx_cons = NEXT_TX(tx_cons); 158 tx_buf = &txr->tx_buf_ring[tx_cons]; 159 page_pool_recycle_direct(rxr->page_pool, tx_buf->page); 160 } 161 } 162 tx_cons = NEXT_TX(tx_cons); 163 } 164 txr->tx_cons = tx_cons; 165 if (rx_doorbell_needed) { 166 tx_buf = &txr->tx_buf_ring[last_tx_cons]; 167 bnxt_db_write(bp, &rxr->rx_db, tx_buf->rx_prod); 168 169 } 170 } 171 172 bool bnxt_xdp_attached(struct bnxt *bp, struct bnxt_rx_ring_info *rxr) 173 { 174 struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog); 175 176 return !!xdp_prog; 177 } 178 179 void bnxt_xdp_buff_init(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, 180 u16 cons, u8 *data_ptr, unsigned int len, 181 struct xdp_buff *xdp) 182 { 183 struct bnxt_sw_rx_bd *rx_buf; 184 u32 buflen = PAGE_SIZE; 185 struct pci_dev *pdev; 186 dma_addr_t mapping; 187 u32 offset; 188 189 pdev = bp->pdev; 190 rx_buf = &rxr->rx_buf_ring[cons]; 191 offset = bp->rx_offset; 192 193 mapping = rx_buf->mapping - bp->rx_dma_offset; 194 dma_sync_single_for_cpu(&pdev->dev, mapping + offset, len, bp->rx_dir); 195 196 xdp_init_buff(xdp, buflen, &rxr->xdp_rxq); 197 xdp_prepare_buff(xdp, data_ptr - offset, offset, len, false); 198 } 199 200 void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr, 201 struct xdp_buff *xdp) 202 { 203 struct skb_shared_info *shinfo; 204 int i; 205 206 if (!xdp || !xdp_buff_has_frags(xdp)) 207 return; 208 shinfo = xdp_get_shared_info_from_buff(xdp); 209 for (i = 0; i < shinfo->nr_frags; i++) { 210 struct page *page = skb_frag_page(&shinfo->frags[i]); 211 212 page_pool_recycle_direct(rxr->page_pool, page); 213 } 214 shinfo->nr_frags = 0; 215 } 216 217 /* returns the following: 218 * true - packet consumed by XDP and new buffer is allocated. 219 * false - packet should be passed to the stack. 220 */ 221 bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, 222 struct xdp_buff xdp, struct page *page, u8 **data_ptr, 223 unsigned int *len, u8 *event) 224 { 225 struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog); 226 struct bnxt_tx_ring_info *txr; 227 struct bnxt_sw_rx_bd *rx_buf; 228 struct pci_dev *pdev; 229 dma_addr_t mapping; 230 u32 tx_needed = 1; 231 void *orig_data; 232 u32 tx_avail; 233 u32 offset; 234 u32 act; 235 236 if (!xdp_prog) 237 return false; 238 239 pdev = bp->pdev; 240 offset = bp->rx_offset; 241 242 txr = rxr->bnapi->tx_ring; 243 /* BNXT_RX_PAGE_MODE(bp) when XDP enabled */ 244 orig_data = xdp.data; 245 246 act = bpf_prog_run_xdp(xdp_prog, &xdp); 247 248 tx_avail = bnxt_tx_avail(bp, txr); 249 /* If the tx ring is not full, we must not update the rx producer yet 250 * because we may still be transmitting on some BDs. 251 */ 252 if (tx_avail != bp->tx_ring_size) 253 *event &= ~BNXT_RX_EVENT; 254 255 *len = xdp.data_end - xdp.data; 256 if (orig_data != xdp.data) { 257 offset = xdp.data - xdp.data_hard_start; 258 *data_ptr = xdp.data_hard_start + offset; 259 } 260 261 switch (act) { 262 case XDP_PASS: 263 return false; 264 265 case XDP_TX: 266 rx_buf = &rxr->rx_buf_ring[cons]; 267 mapping = rx_buf->mapping - bp->rx_dma_offset; 268 *event = 0; 269 270 if (unlikely(xdp_buff_has_frags(&xdp))) { 271 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(&xdp); 272 273 tx_needed += sinfo->nr_frags; 274 *event = BNXT_AGG_EVENT; 275 } 276 277 if (tx_avail < tx_needed) { 278 trace_xdp_exception(bp->dev, xdp_prog, act); 279 bnxt_xdp_buff_frags_free(rxr, &xdp); 280 bnxt_reuse_rx_data(rxr, cons, page); 281 return true; 282 } 283 284 dma_sync_single_for_device(&pdev->dev, mapping + offset, *len, 285 bp->rx_dir); 286 287 *event |= BNXT_TX_EVENT; 288 __bnxt_xmit_xdp(bp, txr, mapping + offset, *len, 289 NEXT_RX(rxr->rx_prod), &xdp); 290 bnxt_reuse_rx_data(rxr, cons, page); 291 return true; 292 case XDP_REDIRECT: 293 /* if we are calling this here then we know that the 294 * redirect is coming from a frame received by the 295 * bnxt_en driver. 296 */ 297 rx_buf = &rxr->rx_buf_ring[cons]; 298 mapping = rx_buf->mapping - bp->rx_dma_offset; 299 dma_unmap_page_attrs(&pdev->dev, mapping, 300 PAGE_SIZE, bp->rx_dir, 301 DMA_ATTR_WEAK_ORDERING); 302 303 /* if we are unable to allocate a new buffer, abort and reuse */ 304 if (bnxt_alloc_rx_data(bp, rxr, rxr->rx_prod, GFP_ATOMIC)) { 305 trace_xdp_exception(bp->dev, xdp_prog, act); 306 bnxt_xdp_buff_frags_free(rxr, &xdp); 307 bnxt_reuse_rx_data(rxr, cons, page); 308 return true; 309 } 310 311 if (xdp_do_redirect(bp->dev, &xdp, xdp_prog)) { 312 trace_xdp_exception(bp->dev, xdp_prog, act); 313 page_pool_recycle_direct(rxr->page_pool, page); 314 return true; 315 } 316 317 *event |= BNXT_REDIRECT_EVENT; 318 break; 319 default: 320 bpf_warn_invalid_xdp_action(bp->dev, xdp_prog, act); 321 fallthrough; 322 case XDP_ABORTED: 323 trace_xdp_exception(bp->dev, xdp_prog, act); 324 fallthrough; 325 case XDP_DROP: 326 bnxt_xdp_buff_frags_free(rxr, &xdp); 327 bnxt_reuse_rx_data(rxr, cons, page); 328 break; 329 } 330 return true; 331 } 332 333 int bnxt_xdp_xmit(struct net_device *dev, int num_frames, 334 struct xdp_frame **frames, u32 flags) 335 { 336 struct bnxt *bp = netdev_priv(dev); 337 struct bpf_prog *xdp_prog = READ_ONCE(bp->xdp_prog); 338 struct pci_dev *pdev = bp->pdev; 339 struct bnxt_tx_ring_info *txr; 340 dma_addr_t mapping; 341 int nxmit = 0; 342 int ring; 343 int i; 344 345 if (!test_bit(BNXT_STATE_OPEN, &bp->state) || 346 !bp->tx_nr_rings_xdp || 347 !xdp_prog) 348 return -EINVAL; 349 350 ring = smp_processor_id() % bp->tx_nr_rings_xdp; 351 txr = &bp->tx_ring[ring]; 352 353 if (READ_ONCE(txr->dev_state) == BNXT_DEV_STATE_CLOSING) 354 return -EINVAL; 355 356 if (static_branch_unlikely(&bnxt_xdp_locking_key)) 357 spin_lock(&txr->xdp_tx_lock); 358 359 for (i = 0; i < num_frames; i++) { 360 struct xdp_frame *xdp = frames[i]; 361 362 if (!bnxt_tx_avail(bp, txr)) 363 break; 364 365 mapping = dma_map_single(&pdev->dev, xdp->data, xdp->len, 366 DMA_TO_DEVICE); 367 368 if (dma_mapping_error(&pdev->dev, mapping)) 369 break; 370 371 __bnxt_xmit_xdp_redirect(bp, txr, mapping, xdp->len, xdp); 372 nxmit++; 373 } 374 375 if (flags & XDP_XMIT_FLUSH) { 376 /* Sync BD data before updating doorbell */ 377 wmb(); 378 bnxt_db_write(bp, &txr->tx_db, txr->tx_prod); 379 } 380 381 if (static_branch_unlikely(&bnxt_xdp_locking_key)) 382 spin_unlock(&txr->xdp_tx_lock); 383 384 return nxmit; 385 } 386 387 /* Under rtnl_lock */ 388 static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog) 389 { 390 struct net_device *dev = bp->dev; 391 int tx_xdp = 0, rc, tc; 392 struct bpf_prog *old; 393 394 if (prog && !prog->aux->xdp_has_frags && 395 bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) { 396 netdev_warn(dev, "MTU %d larger than %d without XDP frag support.\n", 397 bp->dev->mtu, BNXT_MAX_PAGE_MODE_MTU); 398 return -EOPNOTSUPP; 399 } 400 if (!(bp->flags & BNXT_FLAG_SHARED_RINGS)) { 401 netdev_warn(dev, "ethtool rx/tx channels must be combined to support XDP.\n"); 402 return -EOPNOTSUPP; 403 } 404 if (prog) 405 tx_xdp = bp->rx_nr_rings; 406 407 tc = netdev_get_num_tc(dev); 408 if (!tc) 409 tc = 1; 410 rc = bnxt_check_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings, 411 true, tc, tx_xdp); 412 if (rc) { 413 netdev_warn(dev, "Unable to reserve enough TX rings to support XDP.\n"); 414 return rc; 415 } 416 if (netif_running(dev)) 417 bnxt_close_nic(bp, true, false); 418 419 old = xchg(&bp->xdp_prog, prog); 420 if (old) 421 bpf_prog_put(old); 422 423 if (prog) { 424 bnxt_set_rx_skb_mode(bp, true); 425 xdp_features_set_redirect_target(dev, true); 426 } else { 427 int rx, tx; 428 429 xdp_features_clear_redirect_target(dev); 430 bnxt_set_rx_skb_mode(bp, false); 431 bnxt_get_max_rings(bp, &rx, &tx, true); 432 if (rx > 1) { 433 bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS; 434 bp->dev->hw_features |= NETIF_F_LRO; 435 } 436 } 437 bp->tx_nr_rings_xdp = tx_xdp; 438 bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp; 439 bp->cp_nr_rings = max_t(int, bp->tx_nr_rings, bp->rx_nr_rings); 440 bnxt_set_tpa_flags(bp); 441 bnxt_set_ring_params(bp); 442 443 if (netif_running(dev)) 444 return bnxt_open_nic(bp, true, false); 445 446 return 0; 447 } 448 449 int bnxt_xdp(struct net_device *dev, struct netdev_bpf *xdp) 450 { 451 struct bnxt *bp = netdev_priv(dev); 452 int rc; 453 454 switch (xdp->command) { 455 case XDP_SETUP_PROG: 456 rc = bnxt_xdp_set(bp, xdp->prog); 457 break; 458 default: 459 rc = -EINVAL; 460 break; 461 } 462 return rc; 463 } 464 465 struct sk_buff * 466 bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags, 467 struct page_pool *pool, struct xdp_buff *xdp, 468 struct rx_cmp_ext *rxcmp1) 469 { 470 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); 471 472 if (!skb) 473 return NULL; 474 skb_checksum_none_assert(skb); 475 if (RX_CMP_L4_CS_OK(rxcmp1)) { 476 if (bp->dev->features & NETIF_F_RXCSUM) { 477 skb->ip_summed = CHECKSUM_UNNECESSARY; 478 skb->csum_level = RX_CMP_ENCAP(rxcmp1); 479 } 480 } 481 xdp_update_skb_shared_info(skb, num_frags, 482 sinfo->xdp_frags_size, 483 PAGE_SIZE * sinfo->nr_frags, 484 xdp_buff_is_frag_pfmemalloc(xdp)); 485 return skb; 486 } 487