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, *first_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 first_buf = tx_buf; 47 tx_buf->nr_frags = num_frags; 48 if (xdp) 49 tx_buf->page = virt_to_head_page(xdp->data); 50 51 txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)]; 52 flags = ((len) << TX_BD_LEN_SHIFT) | ((num_frags + 1) << TX_BD_FLAGS_BD_CNT_SHIFT); 53 txbd->tx_bd_len_flags_type = cpu_to_le32(flags); 54 txbd->tx_bd_opaque = prod; 55 txbd->tx_bd_haddr = cpu_to_le64(mapping); 56 57 /* now let us fill up the frags into the next buffers */ 58 for (i = 0; i < num_frags ; i++) { 59 skb_frag_t *frag = &sinfo->frags[i]; 60 struct bnxt_sw_tx_bd *frag_tx_buf; 61 struct pci_dev *pdev = bp->pdev; 62 dma_addr_t frag_mapping; 63 int frag_len; 64 65 prod = NEXT_TX(prod); 66 txr->tx_prod = prod; 67 68 /* first fill up the first buffer */ 69 frag_tx_buf = &txr->tx_buf_ring[prod]; 70 frag_tx_buf->page = skb_frag_page(frag); 71 72 txbd = &txr->tx_desc_ring[TX_RING(prod)][TX_IDX(prod)]; 73 74 frag_len = skb_frag_size(frag); 75 frag_mapping = skb_frag_dma_map(&pdev->dev, frag, 0, 76 frag_len, DMA_TO_DEVICE); 77 78 if (unlikely(dma_mapping_error(&pdev->dev, frag_mapping))) 79 return NULL; 80 81 dma_unmap_addr_set(frag_tx_buf, mapping, frag_mapping); 82 83 flags = frag_len << TX_BD_LEN_SHIFT; 84 txbd->tx_bd_len_flags_type = cpu_to_le32(flags); 85 txbd->tx_bd_opaque = prod; 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 first_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 struct pci_dev *pdev; 185 dma_addr_t mapping; 186 u32 offset; 187 188 pdev = bp->pdev; 189 rx_buf = &rxr->rx_buf_ring[cons]; 190 offset = bp->rx_offset; 191 192 mapping = rx_buf->mapping - bp->rx_dma_offset; 193 dma_sync_single_for_cpu(&pdev->dev, mapping + offset, *len, bp->rx_dir); 194 195 xdp_init_buff(xdp, BNXT_PAGE_MODE_BUF_SIZE + offset, &rxr->xdp_rxq); 196 xdp_prepare_buff(xdp, *data_ptr - offset, offset, *len, false); 197 } 198 199 void bnxt_xdp_buff_frags_free(struct bnxt_rx_ring_info *rxr, 200 struct xdp_buff *xdp) 201 { 202 struct skb_shared_info *shinfo; 203 int i; 204 205 if (!xdp || !xdp_buff_has_frags(xdp)) 206 return; 207 shinfo = xdp_get_shared_info_from_buff(xdp); 208 for (i = 0; i < shinfo->nr_frags; i++) { 209 struct page *page = skb_frag_page(&shinfo->frags[i]); 210 211 page_pool_recycle_direct(rxr->page_pool, page); 212 } 213 shinfo->nr_frags = 0; 214 } 215 216 /* returns the following: 217 * true - packet consumed by XDP and new buffer is allocated. 218 * false - packet should be passed to the stack. 219 */ 220 bool bnxt_rx_xdp(struct bnxt *bp, struct bnxt_rx_ring_info *rxr, u16 cons, 221 struct xdp_buff xdp, struct page *page, unsigned int *len, u8 *event) 222 { 223 struct bpf_prog *xdp_prog = READ_ONCE(rxr->xdp_prog); 224 struct bnxt_tx_ring_info *txr; 225 struct bnxt_sw_rx_bd *rx_buf; 226 struct pci_dev *pdev; 227 dma_addr_t mapping; 228 u32 tx_needed = 1; 229 void *orig_data; 230 u32 tx_avail; 231 u32 offset; 232 u32 act; 233 234 if (!xdp_prog) 235 return false; 236 237 pdev = bp->pdev; 238 offset = bp->rx_offset; 239 240 txr = rxr->bnapi->tx_ring; 241 /* BNXT_RX_PAGE_MODE(bp) when XDP enabled */ 242 orig_data = xdp.data; 243 244 act = bpf_prog_run_xdp(xdp_prog, &xdp); 245 246 tx_avail = bnxt_tx_avail(bp, txr); 247 /* If the tx ring is not full, we must not update the rx producer yet 248 * because we may still be transmitting on some BDs. 249 */ 250 if (tx_avail != bp->tx_ring_size) 251 *event &= ~BNXT_RX_EVENT; 252 253 *len = xdp.data_end - xdp.data; 254 if (orig_data != xdp.data) 255 offset = xdp.data - xdp.data_hard_start; 256 257 switch (act) { 258 case XDP_PASS: 259 return false; 260 261 case XDP_TX: 262 rx_buf = &rxr->rx_buf_ring[cons]; 263 mapping = rx_buf->mapping - bp->rx_dma_offset; 264 *event = 0; 265 266 if (unlikely(xdp_buff_has_frags(&xdp))) { 267 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(&xdp); 268 269 tx_needed += sinfo->nr_frags; 270 *event = BNXT_AGG_EVENT; 271 } 272 273 if (tx_avail < tx_needed) { 274 trace_xdp_exception(bp->dev, xdp_prog, act); 275 bnxt_xdp_buff_frags_free(rxr, &xdp); 276 bnxt_reuse_rx_data(rxr, cons, page); 277 return true; 278 } 279 280 dma_sync_single_for_device(&pdev->dev, mapping + offset, *len, 281 bp->rx_dir); 282 283 *event |= BNXT_TX_EVENT; 284 __bnxt_xmit_xdp(bp, txr, mapping + offset, *len, 285 NEXT_RX(rxr->rx_prod), &xdp); 286 bnxt_reuse_rx_data(rxr, cons, page); 287 return true; 288 case XDP_REDIRECT: 289 /* if we are calling this here then we know that the 290 * redirect is coming from a frame received by the 291 * bnxt_en driver. 292 */ 293 rx_buf = &rxr->rx_buf_ring[cons]; 294 mapping = rx_buf->mapping - bp->rx_dma_offset; 295 dma_unmap_page_attrs(&pdev->dev, mapping, 296 PAGE_SIZE, bp->rx_dir, 297 DMA_ATTR_WEAK_ORDERING); 298 299 /* if we are unable to allocate a new buffer, abort and reuse */ 300 if (bnxt_alloc_rx_data(bp, rxr, rxr->rx_prod, GFP_ATOMIC)) { 301 trace_xdp_exception(bp->dev, xdp_prog, act); 302 bnxt_xdp_buff_frags_free(rxr, &xdp); 303 bnxt_reuse_rx_data(rxr, cons, page); 304 return true; 305 } 306 307 if (xdp_do_redirect(bp->dev, &xdp, xdp_prog)) { 308 trace_xdp_exception(bp->dev, xdp_prog, act); 309 page_pool_recycle_direct(rxr->page_pool, page); 310 return true; 311 } 312 313 *event |= BNXT_REDIRECT_EVENT; 314 break; 315 default: 316 bpf_warn_invalid_xdp_action(bp->dev, xdp_prog, act); 317 fallthrough; 318 case XDP_ABORTED: 319 trace_xdp_exception(bp->dev, xdp_prog, act); 320 fallthrough; 321 case XDP_DROP: 322 bnxt_xdp_buff_frags_free(rxr, &xdp); 323 bnxt_reuse_rx_data(rxr, cons, page); 324 break; 325 } 326 return true; 327 } 328 329 int bnxt_xdp_xmit(struct net_device *dev, int num_frames, 330 struct xdp_frame **frames, u32 flags) 331 { 332 struct bnxt *bp = netdev_priv(dev); 333 struct bpf_prog *xdp_prog = READ_ONCE(bp->xdp_prog); 334 struct pci_dev *pdev = bp->pdev; 335 struct bnxt_tx_ring_info *txr; 336 dma_addr_t mapping; 337 int nxmit = 0; 338 int ring; 339 int i; 340 341 if (!test_bit(BNXT_STATE_OPEN, &bp->state) || 342 !bp->tx_nr_rings_xdp || 343 !xdp_prog) 344 return -EINVAL; 345 346 ring = smp_processor_id() % bp->tx_nr_rings_xdp; 347 txr = &bp->tx_ring[ring]; 348 349 if (READ_ONCE(txr->dev_state) == BNXT_DEV_STATE_CLOSING) 350 return -EINVAL; 351 352 if (static_branch_unlikely(&bnxt_xdp_locking_key)) 353 spin_lock(&txr->xdp_tx_lock); 354 355 for (i = 0; i < num_frames; i++) { 356 struct xdp_frame *xdp = frames[i]; 357 358 if (!bnxt_tx_avail(bp, txr)) 359 break; 360 361 mapping = dma_map_single(&pdev->dev, xdp->data, xdp->len, 362 DMA_TO_DEVICE); 363 364 if (dma_mapping_error(&pdev->dev, mapping)) 365 break; 366 367 __bnxt_xmit_xdp_redirect(bp, txr, mapping, xdp->len, xdp); 368 nxmit++; 369 } 370 371 if (flags & XDP_XMIT_FLUSH) { 372 /* Sync BD data before updating doorbell */ 373 wmb(); 374 bnxt_db_write(bp, &txr->tx_db, txr->tx_prod); 375 } 376 377 if (static_branch_unlikely(&bnxt_xdp_locking_key)) 378 spin_unlock(&txr->xdp_tx_lock); 379 380 return nxmit; 381 } 382 383 /* Under rtnl_lock */ 384 static int bnxt_xdp_set(struct bnxt *bp, struct bpf_prog *prog) 385 { 386 struct net_device *dev = bp->dev; 387 int tx_xdp = 0, rc, tc; 388 struct bpf_prog *old; 389 390 if (prog && !prog->aux->xdp_has_frags && 391 bp->dev->mtu > BNXT_MAX_PAGE_MODE_MTU) { 392 netdev_warn(dev, "MTU %d larger than %d without XDP frag support.\n", 393 bp->dev->mtu, BNXT_MAX_PAGE_MODE_MTU); 394 return -EOPNOTSUPP; 395 } 396 if (!(bp->flags & BNXT_FLAG_SHARED_RINGS)) { 397 netdev_warn(dev, "ethtool rx/tx channels must be combined to support XDP.\n"); 398 return -EOPNOTSUPP; 399 } 400 if (prog) 401 tx_xdp = bp->rx_nr_rings; 402 403 tc = netdev_get_num_tc(dev); 404 if (!tc) 405 tc = 1; 406 rc = bnxt_check_rings(bp, bp->tx_nr_rings_per_tc, bp->rx_nr_rings, 407 true, tc, tx_xdp); 408 if (rc) { 409 netdev_warn(dev, "Unable to reserve enough TX rings to support XDP.\n"); 410 return rc; 411 } 412 if (netif_running(dev)) 413 bnxt_close_nic(bp, true, false); 414 415 old = xchg(&bp->xdp_prog, prog); 416 if (old) 417 bpf_prog_put(old); 418 419 if (prog) { 420 bnxt_set_rx_skb_mode(bp, true); 421 } else { 422 int rx, tx; 423 424 bnxt_set_rx_skb_mode(bp, false); 425 bnxt_get_max_rings(bp, &rx, &tx, true); 426 if (rx > 1) { 427 bp->flags &= ~BNXT_FLAG_NO_AGG_RINGS; 428 bp->dev->hw_features |= NETIF_F_LRO; 429 } 430 } 431 bp->tx_nr_rings_xdp = tx_xdp; 432 bp->tx_nr_rings = bp->tx_nr_rings_per_tc * tc + tx_xdp; 433 bp->cp_nr_rings = max_t(int, bp->tx_nr_rings, bp->rx_nr_rings); 434 bnxt_set_tpa_flags(bp); 435 bnxt_set_ring_params(bp); 436 437 if (netif_running(dev)) 438 return bnxt_open_nic(bp, true, false); 439 440 return 0; 441 } 442 443 int bnxt_xdp(struct net_device *dev, struct netdev_bpf *xdp) 444 { 445 struct bnxt *bp = netdev_priv(dev); 446 int rc; 447 448 switch (xdp->command) { 449 case XDP_SETUP_PROG: 450 rc = bnxt_xdp_set(bp, xdp->prog); 451 break; 452 default: 453 rc = -EINVAL; 454 break; 455 } 456 return rc; 457 } 458 459 struct sk_buff * 460 bnxt_xdp_build_skb(struct bnxt *bp, struct sk_buff *skb, u8 num_frags, 461 struct page_pool *pool, struct xdp_buff *xdp, 462 struct rx_cmp_ext *rxcmp1) 463 { 464 struct skb_shared_info *sinfo = xdp_get_shared_info_from_buff(xdp); 465 466 if (!skb) 467 return NULL; 468 skb_checksum_none_assert(skb); 469 if (RX_CMP_L4_CS_OK(rxcmp1)) { 470 if (bp->dev->features & NETIF_F_RXCSUM) { 471 skb->ip_summed = CHECKSUM_UNNECESSARY; 472 skb->csum_level = RX_CMP_ENCAP(rxcmp1); 473 } 474 } 475 xdp_update_skb_shared_info(skb, num_frags, 476 sinfo->xdp_frags_size, 477 PAGE_SIZE * sinfo->nr_frags, 478 xdp_buff_is_frag_pfmemalloc(xdp)); 479 return skb; 480 } 481