1 /* SPDX-License-Identifier: BSD-3-Clause 2 * Copyright(c) 2010-2014 Intel Corporation 3 */ 4 5 #ifndef _VIRTQUEUE_H_ 6 #define _VIRTQUEUE_H_ 7 8 #include <stdint.h> 9 10 #include <rte_atomic.h> 11 #include <rte_memory.h> 12 #include <rte_mempool.h> 13 #include <rte_net.h> 14 15 #include "virtio_pci.h" 16 #include "virtio_ring.h" 17 #include "virtio_logs.h" 18 #include "virtio_rxtx.h" 19 20 struct rte_mbuf; 21 22 #define DEFAULT_TX_FREE_THRESH 32 23 #define DEFAULT_RX_FREE_THRESH 32 24 25 #define VIRTIO_MBUF_BURST_SZ 64 26 /* 27 * Per virtio_ring.h in Linux. 28 * For virtio_pci on SMP, we don't need to order with respect to MMIO 29 * accesses through relaxed memory I/O windows, so smp_mb() et al are 30 * sufficient. 31 * 32 * For using virtio to talk to real devices (eg. vDPA) we do need real 33 * barriers. 34 */ 35 static inline void 36 virtio_mb(uint8_t weak_barriers) 37 { 38 if (weak_barriers) 39 rte_smp_mb(); 40 else 41 rte_mb(); 42 } 43 44 static inline void 45 virtio_rmb(uint8_t weak_barriers) 46 { 47 if (weak_barriers) 48 rte_smp_rmb(); 49 else 50 rte_io_rmb(); 51 } 52 53 static inline void 54 virtio_wmb(uint8_t weak_barriers) 55 { 56 if (weak_barriers) 57 rte_smp_wmb(); 58 else 59 rte_io_wmb(); 60 } 61 62 static inline uint16_t 63 virtqueue_fetch_flags_packed(struct vring_packed_desc *dp, 64 uint8_t weak_barriers) 65 { 66 uint16_t flags; 67 68 if (weak_barriers) { 69 /* x86 prefers to using rte_smp_rmb over __atomic_load_n as it reports 70 * a better perf(~1.5%), which comes from the saved branch by the compiler. 71 * The if and else branch are identical with the smp and io barriers both 72 * defined as compiler barriers on x86. 73 */ 74 #ifdef RTE_ARCH_X86_64 75 flags = dp->flags; 76 rte_smp_rmb(); 77 #else 78 flags = __atomic_load_n(&dp->flags, __ATOMIC_ACQUIRE); 79 #endif 80 } else { 81 flags = dp->flags; 82 rte_io_rmb(); 83 } 84 85 return flags; 86 } 87 88 static inline void 89 virtqueue_store_flags_packed(struct vring_packed_desc *dp, 90 uint16_t flags, uint8_t weak_barriers) 91 { 92 if (weak_barriers) { 93 /* x86 prefers to using rte_smp_wmb over __atomic_store_n as it reports 94 * a better perf(~1.5%), which comes from the saved branch by the compiler. 95 * The if and else branch are identical with the smp and io barriers both 96 * defined as compiler barriers on x86. 97 */ 98 #ifdef RTE_ARCH_X86_64 99 rte_smp_wmb(); 100 dp->flags = flags; 101 #else 102 __atomic_store_n(&dp->flags, flags, __ATOMIC_RELEASE); 103 #endif 104 } else { 105 rte_io_wmb(); 106 dp->flags = flags; 107 } 108 } 109 #ifdef RTE_PMD_PACKET_PREFETCH 110 #define rte_packet_prefetch(p) rte_prefetch1(p) 111 #else 112 #define rte_packet_prefetch(p) do {} while(0) 113 #endif 114 115 #define VIRTQUEUE_MAX_NAME_SZ 32 116 117 #ifdef RTE_VIRTIO_USER 118 /** 119 * Return the physical address (or virtual address in case of 120 * virtio-user) of mbuf data buffer. 121 * 122 * The address is firstly casted to the word size (sizeof(uintptr_t)) 123 * before casting it to uint64_t. This is to make it work with different 124 * combination of word size (64 bit and 32 bit) and virtio device 125 * (virtio-pci and virtio-user). 126 */ 127 #define VIRTIO_MBUF_ADDR(mb, vq) \ 128 ((uint64_t)(*(uintptr_t *)((uintptr_t)(mb) + (vq)->offset))) 129 #else 130 #define VIRTIO_MBUF_ADDR(mb, vq) ((mb)->buf_iova) 131 #endif 132 133 /** 134 * Return the physical address (or virtual address in case of 135 * virtio-user) of mbuf data buffer, taking care of mbuf data offset 136 */ 137 #define VIRTIO_MBUF_DATA_DMA_ADDR(mb, vq) \ 138 (VIRTIO_MBUF_ADDR(mb, vq) + (mb)->data_off) 139 140 #define VTNET_SQ_RQ_QUEUE_IDX 0 141 #define VTNET_SQ_TQ_QUEUE_IDX 1 142 #define VTNET_SQ_CQ_QUEUE_IDX 2 143 144 enum { VTNET_RQ = 0, VTNET_TQ = 1, VTNET_CQ = 2 }; 145 /** 146 * The maximum virtqueue size is 2^15. Use that value as the end of 147 * descriptor chain terminator since it will never be a valid index 148 * in the descriptor table. This is used to verify we are correctly 149 * handling vq_free_cnt. 150 */ 151 #define VQ_RING_DESC_CHAIN_END 32768 152 153 /** 154 * Control the RX mode, ie. promiscuous, allmulti, etc... 155 * All commands require an "out" sg entry containing a 1 byte 156 * state value, zero = disable, non-zero = enable. Commands 157 * 0 and 1 are supported with the VIRTIO_NET_F_CTRL_RX feature. 158 * Commands 2-5 are added with VIRTIO_NET_F_CTRL_RX_EXTRA. 159 */ 160 #define VIRTIO_NET_CTRL_RX 0 161 #define VIRTIO_NET_CTRL_RX_PROMISC 0 162 #define VIRTIO_NET_CTRL_RX_ALLMULTI 1 163 #define VIRTIO_NET_CTRL_RX_ALLUNI 2 164 #define VIRTIO_NET_CTRL_RX_NOMULTI 3 165 #define VIRTIO_NET_CTRL_RX_NOUNI 4 166 #define VIRTIO_NET_CTRL_RX_NOBCAST 5 167 168 /** 169 * Control the MAC 170 * 171 * The MAC filter table is managed by the hypervisor, the guest should 172 * assume the size is infinite. Filtering should be considered 173 * non-perfect, ie. based on hypervisor resources, the guest may 174 * received packets from sources not specified in the filter list. 175 * 176 * In addition to the class/cmd header, the TABLE_SET command requires 177 * two out scatterlists. Each contains a 4 byte count of entries followed 178 * by a concatenated byte stream of the ETH_ALEN MAC addresses. The 179 * first sg list contains unicast addresses, the second is for multicast. 180 * This functionality is present if the VIRTIO_NET_F_CTRL_RX feature 181 * is available. 182 * 183 * The ADDR_SET command requests one out scatterlist, it contains a 184 * 6 bytes MAC address. This functionality is present if the 185 * VIRTIO_NET_F_CTRL_MAC_ADDR feature is available. 186 */ 187 struct virtio_net_ctrl_mac { 188 uint32_t entries; 189 uint8_t macs[][RTE_ETHER_ADDR_LEN]; 190 } __rte_packed; 191 192 #define VIRTIO_NET_CTRL_MAC 1 193 #define VIRTIO_NET_CTRL_MAC_TABLE_SET 0 194 #define VIRTIO_NET_CTRL_MAC_ADDR_SET 1 195 196 /** 197 * Control VLAN filtering 198 * 199 * The VLAN filter table is controlled via a simple ADD/DEL interface. 200 * VLAN IDs not added may be filtered by the hypervisor. Del is the 201 * opposite of add. Both commands expect an out entry containing a 2 202 * byte VLAN ID. VLAN filtering is available with the 203 * VIRTIO_NET_F_CTRL_VLAN feature bit. 204 */ 205 #define VIRTIO_NET_CTRL_VLAN 2 206 #define VIRTIO_NET_CTRL_VLAN_ADD 0 207 #define VIRTIO_NET_CTRL_VLAN_DEL 1 208 209 /* 210 * Control link announce acknowledgement 211 * 212 * The command VIRTIO_NET_CTRL_ANNOUNCE_ACK is used to indicate that 213 * driver has recevied the notification; device would clear the 214 * VIRTIO_NET_S_ANNOUNCE bit in the status field after it receives 215 * this command. 216 */ 217 #define VIRTIO_NET_CTRL_ANNOUNCE 3 218 #define VIRTIO_NET_CTRL_ANNOUNCE_ACK 0 219 220 struct virtio_net_ctrl_hdr { 221 uint8_t class; 222 uint8_t cmd; 223 } __rte_packed; 224 225 typedef uint8_t virtio_net_ctrl_ack; 226 227 #define VIRTIO_NET_OK 0 228 #define VIRTIO_NET_ERR 1 229 230 #define VIRTIO_MAX_CTRL_DATA 2048 231 232 struct virtio_pmd_ctrl { 233 struct virtio_net_ctrl_hdr hdr; 234 virtio_net_ctrl_ack status; 235 uint8_t data[VIRTIO_MAX_CTRL_DATA]; 236 }; 237 238 struct vq_desc_extra { 239 void *cookie; 240 uint16_t ndescs; 241 uint16_t next; 242 }; 243 244 struct virtqueue { 245 struct virtio_hw *hw; /**< virtio_hw structure pointer. */ 246 union { 247 struct { 248 /**< vring keeping desc, used and avail */ 249 struct vring ring; 250 } vq_split; 251 252 struct { 253 /**< vring keeping descs and events */ 254 struct vring_packed ring; 255 bool used_wrap_counter; 256 uint16_t cached_flags; /**< cached flags for descs */ 257 uint16_t event_flags_shadow; 258 } vq_packed; 259 }; 260 261 uint16_t vq_used_cons_idx; /**< last consumed descriptor */ 262 uint16_t vq_nentries; /**< vring desc numbers */ 263 uint16_t vq_free_cnt; /**< num of desc available */ 264 uint16_t vq_avail_idx; /**< sync until needed */ 265 uint16_t vq_free_thresh; /**< free threshold */ 266 267 void *vq_ring_virt_mem; /**< linear address of vring*/ 268 unsigned int vq_ring_size; 269 270 union { 271 struct virtnet_rx rxq; 272 struct virtnet_tx txq; 273 struct virtnet_ctl cq; 274 }; 275 276 rte_iova_t vq_ring_mem; /**< physical address of vring, 277 * or virtual address for virtio_user. */ 278 279 /** 280 * Head of the free chain in the descriptor table. If 281 * there are no free descriptors, this will be set to 282 * VQ_RING_DESC_CHAIN_END. 283 */ 284 uint16_t vq_desc_head_idx; 285 uint16_t vq_desc_tail_idx; 286 uint16_t vq_queue_index; /**< PCI queue index */ 287 uint16_t offset; /**< relative offset to obtain addr in mbuf */ 288 uint16_t *notify_addr; 289 struct rte_mbuf **sw_ring; /**< RX software ring. */ 290 struct vq_desc_extra vq_descx[0]; 291 }; 292 293 /* If multiqueue is provided by host, then we suppport it. */ 294 #define VIRTIO_NET_CTRL_MQ 4 295 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_SET 0 296 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MIN 1 297 #define VIRTIO_NET_CTRL_MQ_VQ_PAIRS_MAX 0x8000 298 299 /** 300 * This is the first element of the scatter-gather list. If you don't 301 * specify GSO or CSUM features, you can simply ignore the header. 302 */ 303 struct virtio_net_hdr { 304 #define VIRTIO_NET_HDR_F_NEEDS_CSUM 1 /**< Use csum_start,csum_offset*/ 305 #define VIRTIO_NET_HDR_F_DATA_VALID 2 /**< Checksum is valid */ 306 uint8_t flags; 307 #define VIRTIO_NET_HDR_GSO_NONE 0 /**< Not a GSO frame */ 308 #define VIRTIO_NET_HDR_GSO_TCPV4 1 /**< GSO frame, IPv4 TCP (TSO) */ 309 #define VIRTIO_NET_HDR_GSO_UDP 3 /**< GSO frame, IPv4 UDP (UFO) */ 310 #define VIRTIO_NET_HDR_GSO_TCPV6 4 /**< GSO frame, IPv6 TCP */ 311 #define VIRTIO_NET_HDR_GSO_ECN 0x80 /**< TCP has ECN set */ 312 uint8_t gso_type; 313 uint16_t hdr_len; /**< Ethernet + IP + tcp/udp hdrs */ 314 uint16_t gso_size; /**< Bytes to append to hdr_len per frame */ 315 uint16_t csum_start; /**< Position to start checksumming from */ 316 uint16_t csum_offset; /**< Offset after that to place checksum */ 317 }; 318 319 /** 320 * This is the version of the header to use when the MRG_RXBUF 321 * feature has been negotiated. 322 */ 323 struct virtio_net_hdr_mrg_rxbuf { 324 struct virtio_net_hdr hdr; 325 uint16_t num_buffers; /**< Number of merged rx buffers */ 326 }; 327 328 /* Region reserved to allow for transmit header and indirect ring */ 329 #define VIRTIO_MAX_TX_INDIRECT 8 330 struct virtio_tx_region { 331 struct virtio_net_hdr_mrg_rxbuf tx_hdr; 332 union { 333 struct vring_desc tx_indir[VIRTIO_MAX_TX_INDIRECT]; 334 struct vring_packed_desc 335 tx_packed_indir[VIRTIO_MAX_TX_INDIRECT]; 336 } __rte_aligned(16); 337 }; 338 339 static inline int 340 desc_is_used(struct vring_packed_desc *desc, struct virtqueue *vq) 341 { 342 uint16_t used, avail, flags; 343 344 flags = virtqueue_fetch_flags_packed(desc, vq->hw->weak_barriers); 345 used = !!(flags & VRING_PACKED_DESC_F_USED); 346 avail = !!(flags & VRING_PACKED_DESC_F_AVAIL); 347 348 return avail == used && used == vq->vq_packed.used_wrap_counter; 349 } 350 351 static inline void 352 vring_desc_init_packed(struct virtqueue *vq, int n) 353 { 354 int i; 355 for (i = 0; i < n - 1; i++) { 356 vq->vq_packed.ring.desc[i].id = i; 357 vq->vq_descx[i].next = i + 1; 358 } 359 vq->vq_packed.ring.desc[i].id = i; 360 vq->vq_descx[i].next = VQ_RING_DESC_CHAIN_END; 361 } 362 363 /* Chain all the descriptors in the ring with an END */ 364 static inline void 365 vring_desc_init_split(struct vring_desc *dp, uint16_t n) 366 { 367 uint16_t i; 368 369 for (i = 0; i < n - 1; i++) 370 dp[i].next = (uint16_t)(i + 1); 371 dp[i].next = VQ_RING_DESC_CHAIN_END; 372 } 373 374 static inline void 375 vring_desc_init_indirect_packed(struct vring_packed_desc *dp, int n) 376 { 377 int i; 378 for (i = 0; i < n; i++) { 379 dp[i].id = (uint16_t)i; 380 dp[i].flags = VRING_DESC_F_WRITE; 381 } 382 } 383 384 /** 385 * Tell the backend not to interrupt us. Implementation for packed virtqueues. 386 */ 387 static inline void 388 virtqueue_disable_intr_packed(struct virtqueue *vq) 389 { 390 if (vq->vq_packed.event_flags_shadow != RING_EVENT_FLAGS_DISABLE) { 391 vq->vq_packed.event_flags_shadow = RING_EVENT_FLAGS_DISABLE; 392 vq->vq_packed.ring.driver->desc_event_flags = 393 vq->vq_packed.event_flags_shadow; 394 } 395 } 396 397 /** 398 * Tell the backend not to interrupt us. Implementation for split virtqueues. 399 */ 400 static inline void 401 virtqueue_disable_intr_split(struct virtqueue *vq) 402 { 403 vq->vq_split.ring.avail->flags |= VRING_AVAIL_F_NO_INTERRUPT; 404 } 405 406 /** 407 * Tell the backend not to interrupt us. 408 */ 409 static inline void 410 virtqueue_disable_intr(struct virtqueue *vq) 411 { 412 if (vtpci_packed_queue(vq->hw)) 413 virtqueue_disable_intr_packed(vq); 414 else 415 virtqueue_disable_intr_split(vq); 416 } 417 418 /** 419 * Tell the backend to interrupt. Implementation for packed virtqueues. 420 */ 421 static inline void 422 virtqueue_enable_intr_packed(struct virtqueue *vq) 423 { 424 if (vq->vq_packed.event_flags_shadow == RING_EVENT_FLAGS_DISABLE) { 425 vq->vq_packed.event_flags_shadow = RING_EVENT_FLAGS_ENABLE; 426 vq->vq_packed.ring.driver->desc_event_flags = 427 vq->vq_packed.event_flags_shadow; 428 } 429 } 430 431 /** 432 * Tell the backend to interrupt. Implementation for split virtqueues. 433 */ 434 static inline void 435 virtqueue_enable_intr_split(struct virtqueue *vq) 436 { 437 vq->vq_split.ring.avail->flags &= (~VRING_AVAIL_F_NO_INTERRUPT); 438 } 439 440 /** 441 * Tell the backend to interrupt us. 442 */ 443 static inline void 444 virtqueue_enable_intr(struct virtqueue *vq) 445 { 446 if (vtpci_packed_queue(vq->hw)) 447 virtqueue_enable_intr_packed(vq); 448 else 449 virtqueue_enable_intr_split(vq); 450 } 451 452 /** 453 * Dump virtqueue internal structures, for debug purpose only. 454 */ 455 void virtqueue_dump(struct virtqueue *vq); 456 /** 457 * Get all mbufs to be freed. 458 */ 459 struct rte_mbuf *virtqueue_detach_unused(struct virtqueue *vq); 460 461 /* Flush the elements in the used ring. */ 462 void virtqueue_rxvq_flush(struct virtqueue *vq); 463 464 int virtqueue_rxvq_reset_packed(struct virtqueue *vq); 465 466 int virtqueue_txvq_reset_packed(struct virtqueue *vq); 467 468 static inline int 469 virtqueue_full(const struct virtqueue *vq) 470 { 471 return vq->vq_free_cnt == 0; 472 } 473 474 static inline int 475 virtio_get_queue_type(struct virtio_hw *hw, uint16_t vtpci_queue_idx) 476 { 477 if (vtpci_queue_idx == hw->max_queue_pairs * 2) 478 return VTNET_CQ; 479 else if (vtpci_queue_idx % 2 == 0) 480 return VTNET_RQ; 481 else 482 return VTNET_TQ; 483 } 484 485 /* virtqueue_nused has load-acquire or rte_io_rmb insed */ 486 static inline uint16_t 487 virtqueue_nused(const struct virtqueue *vq) 488 { 489 uint16_t idx; 490 491 if (vq->hw->weak_barriers) { 492 /** 493 * x86 prefers to using rte_smp_rmb over __atomic_load_n as it 494 * reports a slightly better perf, which comes from the saved 495 * branch by the compiler. 496 * The if and else branches are identical with the smp and io 497 * barriers both defined as compiler barriers on x86. 498 */ 499 #ifdef RTE_ARCH_X86_64 500 idx = vq->vq_split.ring.used->idx; 501 rte_smp_rmb(); 502 #else 503 idx = __atomic_load_n(&(vq)->vq_split.ring.used->idx, 504 __ATOMIC_ACQUIRE); 505 #endif 506 } else { 507 idx = vq->vq_split.ring.used->idx; 508 rte_io_rmb(); 509 } 510 return idx - vq->vq_used_cons_idx; 511 } 512 513 void vq_ring_free_chain(struct virtqueue *vq, uint16_t desc_idx); 514 void vq_ring_free_chain_packed(struct virtqueue *vq, uint16_t used_idx); 515 void vq_ring_free_inorder(struct virtqueue *vq, uint16_t desc_idx, 516 uint16_t num); 517 518 static inline void 519 vq_update_avail_idx(struct virtqueue *vq) 520 { 521 if (vq->hw->weak_barriers) { 522 /* x86 prefers to using rte_smp_wmb over __atomic_store_n as 523 * it reports a slightly better perf, which comes from the 524 * saved branch by the compiler. 525 * The if and else branches are identical with the smp and 526 * io barriers both defined as compiler barriers on x86. 527 */ 528 #ifdef RTE_ARCH_X86_64 529 rte_smp_wmb(); 530 vq->vq_split.ring.avail->idx = vq->vq_avail_idx; 531 #else 532 __atomic_store_n(&vq->vq_split.ring.avail->idx, 533 vq->vq_avail_idx, __ATOMIC_RELEASE); 534 #endif 535 } else { 536 rte_io_wmb(); 537 vq->vq_split.ring.avail->idx = vq->vq_avail_idx; 538 } 539 } 540 541 static inline void 542 vq_update_avail_ring(struct virtqueue *vq, uint16_t desc_idx) 543 { 544 uint16_t avail_idx; 545 /* 546 * Place the head of the descriptor chain into the next slot and make 547 * it usable to the host. The chain is made available now rather than 548 * deferring to virtqueue_notify() in the hopes that if the host is 549 * currently running on another CPU, we can keep it processing the new 550 * descriptor. 551 */ 552 avail_idx = (uint16_t)(vq->vq_avail_idx & (vq->vq_nentries - 1)); 553 if (unlikely(vq->vq_split.ring.avail->ring[avail_idx] != desc_idx)) 554 vq->vq_split.ring.avail->ring[avail_idx] = desc_idx; 555 vq->vq_avail_idx++; 556 } 557 558 static inline int 559 virtqueue_kick_prepare(struct virtqueue *vq) 560 { 561 /* 562 * Ensure updated avail->idx is visible to vhost before reading 563 * the used->flags. 564 */ 565 virtio_mb(vq->hw->weak_barriers); 566 return !(vq->vq_split.ring.used->flags & VRING_USED_F_NO_NOTIFY); 567 } 568 569 static inline int 570 virtqueue_kick_prepare_packed(struct virtqueue *vq) 571 { 572 uint16_t flags; 573 574 /* 575 * Ensure updated data is visible to vhost before reading the flags. 576 */ 577 virtio_mb(vq->hw->weak_barriers); 578 flags = vq->vq_packed.ring.device->desc_event_flags; 579 580 return flags != RING_EVENT_FLAGS_DISABLE; 581 } 582 583 /* 584 * virtqueue_kick_prepare*() or the virtio_wmb() should be called 585 * before this function to be sure that all the data is visible to vhost. 586 */ 587 static inline void 588 virtqueue_notify(struct virtqueue *vq) 589 { 590 VTPCI_OPS(vq->hw)->notify_queue(vq->hw, vq); 591 } 592 593 #ifdef RTE_LIBRTE_VIRTIO_DEBUG_DUMP 594 #define VIRTQUEUE_DUMP(vq) do { \ 595 uint16_t used_idx, nused; \ 596 used_idx = __atomic_load_n(&(vq)->vq_split.ring.used->idx, \ 597 __ATOMIC_RELAXED); \ 598 nused = (uint16_t)(used_idx - (vq)->vq_used_cons_idx); \ 599 if (vtpci_packed_queue((vq)->hw)) { \ 600 PMD_INIT_LOG(DEBUG, \ 601 "VQ: - size=%d; free=%d; used_cons_idx=%d; avail_idx=%d;" \ 602 " cached_flags=0x%x; used_wrap_counter=%d", \ 603 (vq)->vq_nentries, (vq)->vq_free_cnt, (vq)->vq_used_cons_idx, \ 604 (vq)->vq_avail_idx, (vq)->vq_packed.cached_flags, \ 605 (vq)->vq_packed.used_wrap_counter); \ 606 break; \ 607 } \ 608 PMD_INIT_LOG(DEBUG, \ 609 "VQ: - size=%d; free=%d; used=%d; desc_head_idx=%d;" \ 610 " avail.idx=%d; used_cons_idx=%d; used.idx=%d;" \ 611 " avail.flags=0x%x; used.flags=0x%x", \ 612 (vq)->vq_nentries, (vq)->vq_free_cnt, nused, (vq)->vq_desc_head_idx, \ 613 (vq)->vq_split.ring.avail->idx, (vq)->vq_used_cons_idx, \ 614 __atomic_load_n(&(vq)->vq_split.ring.used->idx, __ATOMIC_RELAXED), \ 615 (vq)->vq_split.ring.avail->flags, (vq)->vq_split.ring.used->flags); \ 616 } while (0) 617 #else 618 #define VIRTQUEUE_DUMP(vq) do { } while (0) 619 #endif 620 621 /* avoid write operation when necessary, to lessen cache issues */ 622 #define ASSIGN_UNLESS_EQUAL(var, val) do { \ 623 typeof(var) *const var_ = &(var); \ 624 typeof(val) const val_ = (val); \ 625 if (*var_ != val_) \ 626 *var_ = val_; \ 627 } while (0) 628 629 #define virtqueue_clear_net_hdr(hdr) do { \ 630 typeof(hdr) hdr_ = (hdr); \ 631 ASSIGN_UNLESS_EQUAL((hdr_)->csum_start, 0); \ 632 ASSIGN_UNLESS_EQUAL((hdr_)->csum_offset, 0); \ 633 ASSIGN_UNLESS_EQUAL((hdr_)->flags, 0); \ 634 ASSIGN_UNLESS_EQUAL((hdr_)->gso_type, 0); \ 635 ASSIGN_UNLESS_EQUAL((hdr_)->gso_size, 0); \ 636 ASSIGN_UNLESS_EQUAL((hdr_)->hdr_len, 0); \ 637 } while (0) 638 639 static inline void 640 virtqueue_xmit_offload(struct virtio_net_hdr *hdr, 641 struct rte_mbuf *cookie, 642 bool offload) 643 { 644 if (offload) { 645 if (cookie->ol_flags & PKT_TX_TCP_SEG) 646 cookie->ol_flags |= PKT_TX_TCP_CKSUM; 647 648 switch (cookie->ol_flags & PKT_TX_L4_MASK) { 649 case PKT_TX_UDP_CKSUM: 650 hdr->csum_start = cookie->l2_len + cookie->l3_len; 651 hdr->csum_offset = offsetof(struct rte_udp_hdr, 652 dgram_cksum); 653 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 654 break; 655 656 case PKT_TX_TCP_CKSUM: 657 hdr->csum_start = cookie->l2_len + cookie->l3_len; 658 hdr->csum_offset = offsetof(struct rte_tcp_hdr, cksum); 659 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM; 660 break; 661 662 default: 663 ASSIGN_UNLESS_EQUAL(hdr->csum_start, 0); 664 ASSIGN_UNLESS_EQUAL(hdr->csum_offset, 0); 665 ASSIGN_UNLESS_EQUAL(hdr->flags, 0); 666 break; 667 } 668 669 /* TCP Segmentation Offload */ 670 if (cookie->ol_flags & PKT_TX_TCP_SEG) { 671 hdr->gso_type = (cookie->ol_flags & PKT_TX_IPV6) ? 672 VIRTIO_NET_HDR_GSO_TCPV6 : 673 VIRTIO_NET_HDR_GSO_TCPV4; 674 hdr->gso_size = cookie->tso_segsz; 675 hdr->hdr_len = 676 cookie->l2_len + 677 cookie->l3_len + 678 cookie->l4_len; 679 } else { 680 ASSIGN_UNLESS_EQUAL(hdr->gso_type, 0); 681 ASSIGN_UNLESS_EQUAL(hdr->gso_size, 0); 682 ASSIGN_UNLESS_EQUAL(hdr->hdr_len, 0); 683 } 684 } 685 } 686 687 static inline void 688 virtqueue_enqueue_xmit_packed(struct virtnet_tx *txvq, struct rte_mbuf *cookie, 689 uint16_t needed, int use_indirect, int can_push, 690 int in_order) 691 { 692 struct virtio_tx_region *txr = txvq->virtio_net_hdr_mz->addr; 693 struct vq_desc_extra *dxp; 694 struct virtqueue *vq = txvq->vq; 695 struct vring_packed_desc *start_dp, *head_dp; 696 uint16_t idx, id, head_idx, head_flags; 697 int16_t head_size = vq->hw->vtnet_hdr_size; 698 struct virtio_net_hdr *hdr; 699 uint16_t prev; 700 bool prepend_header = false; 701 702 id = in_order ? vq->vq_avail_idx : vq->vq_desc_head_idx; 703 704 dxp = &vq->vq_descx[id]; 705 dxp->ndescs = needed; 706 dxp->cookie = cookie; 707 708 head_idx = vq->vq_avail_idx; 709 idx = head_idx; 710 prev = head_idx; 711 start_dp = vq->vq_packed.ring.desc; 712 713 head_dp = &vq->vq_packed.ring.desc[idx]; 714 head_flags = cookie->next ? VRING_DESC_F_NEXT : 0; 715 head_flags |= vq->vq_packed.cached_flags; 716 717 if (can_push) { 718 /* prepend cannot fail, checked by caller */ 719 hdr = rte_pktmbuf_mtod_offset(cookie, struct virtio_net_hdr *, 720 -head_size); 721 prepend_header = true; 722 723 /* if offload disabled, it is not zeroed below, do it now */ 724 if (!vq->hw->has_tx_offload) 725 virtqueue_clear_net_hdr(hdr); 726 } else if (use_indirect) { 727 /* setup tx ring slot to point to indirect 728 * descriptor list stored in reserved region. 729 * 730 * the first slot in indirect ring is already preset 731 * to point to the header in reserved region 732 */ 733 start_dp[idx].addr = txvq->virtio_net_hdr_mem + 734 RTE_PTR_DIFF(&txr[idx].tx_packed_indir, txr); 735 start_dp[idx].len = (needed + 1) * 736 sizeof(struct vring_packed_desc); 737 /* reset flags for indirect desc */ 738 head_flags = VRING_DESC_F_INDIRECT; 739 head_flags |= vq->vq_packed.cached_flags; 740 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr; 741 742 /* loop below will fill in rest of the indirect elements */ 743 start_dp = txr[idx].tx_packed_indir; 744 idx = 1; 745 } else { 746 /* setup first tx ring slot to point to header 747 * stored in reserved region. 748 */ 749 start_dp[idx].addr = txvq->virtio_net_hdr_mem + 750 RTE_PTR_DIFF(&txr[idx].tx_hdr, txr); 751 start_dp[idx].len = vq->hw->vtnet_hdr_size; 752 hdr = (struct virtio_net_hdr *)&txr[idx].tx_hdr; 753 idx++; 754 if (idx >= vq->vq_nentries) { 755 idx -= vq->vq_nentries; 756 vq->vq_packed.cached_flags ^= 757 VRING_PACKED_DESC_F_AVAIL_USED; 758 } 759 } 760 761 virtqueue_xmit_offload(hdr, cookie, vq->hw->has_tx_offload); 762 763 do { 764 uint16_t flags; 765 766 start_dp[idx].addr = VIRTIO_MBUF_DATA_DMA_ADDR(cookie, vq); 767 start_dp[idx].len = cookie->data_len; 768 if (prepend_header) { 769 start_dp[idx].addr -= head_size; 770 start_dp[idx].len += head_size; 771 prepend_header = false; 772 } 773 774 if (likely(idx != head_idx)) { 775 flags = cookie->next ? VRING_DESC_F_NEXT : 0; 776 flags |= vq->vq_packed.cached_flags; 777 start_dp[idx].flags = flags; 778 } 779 prev = idx; 780 idx++; 781 if (idx >= vq->vq_nentries) { 782 idx -= vq->vq_nentries; 783 vq->vq_packed.cached_flags ^= 784 VRING_PACKED_DESC_F_AVAIL_USED; 785 } 786 } while ((cookie = cookie->next) != NULL); 787 788 start_dp[prev].id = id; 789 790 if (use_indirect) { 791 idx = head_idx; 792 if (++idx >= vq->vq_nentries) { 793 idx -= vq->vq_nentries; 794 vq->vq_packed.cached_flags ^= 795 VRING_PACKED_DESC_F_AVAIL_USED; 796 } 797 } 798 799 vq->vq_free_cnt = (uint16_t)(vq->vq_free_cnt - needed); 800 vq->vq_avail_idx = idx; 801 802 if (!in_order) { 803 vq->vq_desc_head_idx = dxp->next; 804 if (vq->vq_desc_head_idx == VQ_RING_DESC_CHAIN_END) 805 vq->vq_desc_tail_idx = VQ_RING_DESC_CHAIN_END; 806 } 807 808 virtqueue_store_flags_packed(head_dp, head_flags, 809 vq->hw->weak_barriers); 810 } 811 812 static void 813 vq_ring_free_id_packed(struct virtqueue *vq, uint16_t id) 814 { 815 struct vq_desc_extra *dxp; 816 817 dxp = &vq->vq_descx[id]; 818 vq->vq_free_cnt += dxp->ndescs; 819 820 if (vq->vq_desc_tail_idx == VQ_RING_DESC_CHAIN_END) 821 vq->vq_desc_head_idx = id; 822 else 823 vq->vq_descx[vq->vq_desc_tail_idx].next = id; 824 825 vq->vq_desc_tail_idx = id; 826 dxp->next = VQ_RING_DESC_CHAIN_END; 827 } 828 829 static void 830 virtio_xmit_cleanup_inorder_packed(struct virtqueue *vq, int num) 831 { 832 uint16_t used_idx, id, curr_id, free_cnt = 0; 833 uint16_t size = vq->vq_nentries; 834 struct vring_packed_desc *desc = vq->vq_packed.ring.desc; 835 struct vq_desc_extra *dxp; 836 837 used_idx = vq->vq_used_cons_idx; 838 /* desc_is_used has a load-acquire or rte_io_rmb inside 839 * and wait for used desc in virtqueue. 840 */ 841 while (num > 0 && desc_is_used(&desc[used_idx], vq)) { 842 id = desc[used_idx].id; 843 do { 844 curr_id = used_idx; 845 dxp = &vq->vq_descx[used_idx]; 846 used_idx += dxp->ndescs; 847 free_cnt += dxp->ndescs; 848 num -= dxp->ndescs; 849 if (used_idx >= size) { 850 used_idx -= size; 851 vq->vq_packed.used_wrap_counter ^= 1; 852 } 853 if (dxp->cookie != NULL) { 854 rte_pktmbuf_free(dxp->cookie); 855 dxp->cookie = NULL; 856 } 857 } while (curr_id != id); 858 } 859 vq->vq_used_cons_idx = used_idx; 860 vq->vq_free_cnt += free_cnt; 861 } 862 863 static void 864 virtio_xmit_cleanup_normal_packed(struct virtqueue *vq, int num) 865 { 866 uint16_t used_idx, id; 867 uint16_t size = vq->vq_nentries; 868 struct vring_packed_desc *desc = vq->vq_packed.ring.desc; 869 struct vq_desc_extra *dxp; 870 871 used_idx = vq->vq_used_cons_idx; 872 /* desc_is_used has a load-acquire or rte_io_rmb inside 873 * and wait for used desc in virtqueue. 874 */ 875 while (num-- && desc_is_used(&desc[used_idx], vq)) { 876 id = desc[used_idx].id; 877 dxp = &vq->vq_descx[id]; 878 vq->vq_used_cons_idx += dxp->ndescs; 879 if (vq->vq_used_cons_idx >= size) { 880 vq->vq_used_cons_idx -= size; 881 vq->vq_packed.used_wrap_counter ^= 1; 882 } 883 vq_ring_free_id_packed(vq, id); 884 if (dxp->cookie != NULL) { 885 rte_pktmbuf_free(dxp->cookie); 886 dxp->cookie = NULL; 887 } 888 used_idx = vq->vq_used_cons_idx; 889 } 890 } 891 892 /* Cleanup from completed transmits. */ 893 static inline void 894 virtio_xmit_cleanup_packed(struct virtqueue *vq, int num, int in_order) 895 { 896 if (in_order) 897 virtio_xmit_cleanup_inorder_packed(vq, num); 898 else 899 virtio_xmit_cleanup_normal_packed(vq, num); 900 } 901 902 static inline void 903 virtio_xmit_cleanup(struct virtqueue *vq, uint16_t num) 904 { 905 uint16_t i, used_idx, desc_idx; 906 for (i = 0; i < num; i++) { 907 struct vring_used_elem *uep; 908 struct vq_desc_extra *dxp; 909 910 used_idx = (uint16_t)(vq->vq_used_cons_idx & 911 (vq->vq_nentries - 1)); 912 uep = &vq->vq_split.ring.used->ring[used_idx]; 913 914 desc_idx = (uint16_t)uep->id; 915 dxp = &vq->vq_descx[desc_idx]; 916 vq->vq_used_cons_idx++; 917 vq_ring_free_chain(vq, desc_idx); 918 919 if (dxp->cookie != NULL) { 920 rte_pktmbuf_free(dxp->cookie); 921 dxp->cookie = NULL; 922 } 923 } 924 } 925 926 /* Cleanup from completed inorder transmits. */ 927 static __rte_always_inline void 928 virtio_xmit_cleanup_inorder(struct virtqueue *vq, uint16_t num) 929 { 930 uint16_t i, idx = vq->vq_used_cons_idx; 931 int16_t free_cnt = 0; 932 struct vq_desc_extra *dxp = NULL; 933 934 if (unlikely(num == 0)) 935 return; 936 937 for (i = 0; i < num; i++) { 938 dxp = &vq->vq_descx[idx++ & (vq->vq_nentries - 1)]; 939 free_cnt += dxp->ndescs; 940 if (dxp->cookie != NULL) { 941 rte_pktmbuf_free(dxp->cookie); 942 dxp->cookie = NULL; 943 } 944 } 945 946 vq->vq_free_cnt += free_cnt; 947 vq->vq_used_cons_idx = idx; 948 } 949 #endif /* _VIRTQUEUE_H_ */ 950