4 * Copyright(c) 2010-2016 Intel Corporation. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
11 * * Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * * Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in
15 * the documentation and/or other materials provided with the
17 * * Neither the name of Intel Corporation nor the names of its
18 * contributors may be used to endorse or promote products derived
19 * from this software without specific prior written permission.
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22 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 #include <linux/virtio_net.h>
39 #include <rte_memcpy.h>
40 #include <rte_ether.h>
42 #include <rte_virtio_net.h>
47 #include <rte_spinlock.h>
48 #include <rte_malloc.h>
52 #define MAX_PKT_BURST 32
53 #define VHOST_LOG_PAGE 4096
56 * Atomically set a bit in memory.
58 static inline void __attribute__((always_inline))
59 vhost_set_bit(unsigned int nr, volatile uint8_t *addr)
61 __sync_fetch_and_or_8(addr, (1U << nr));
64 static inline void __attribute__((always_inline))
65 vhost_log_page(uint8_t *log_base, uint64_t page)
67 vhost_set_bit(page % 8, &log_base[page / 8]);
70 static inline void __attribute__((always_inline))
71 vhost_log_write(struct virtio_net *dev, uint64_t addr, uint64_t len)
75 if (likely(((dev->features & (1ULL << VHOST_F_LOG_ALL)) == 0) ||
76 !dev->log_base || !len))
79 if (unlikely(dev->log_size <= ((addr + len - 1) / VHOST_LOG_PAGE / 8)))
82 /* To make sure guest memory updates are committed before logging */
85 page = addr / VHOST_LOG_PAGE;
86 while (page * VHOST_LOG_PAGE < addr + len) {
87 vhost_log_page((uint8_t *)(uintptr_t)dev->log_base, page);
92 static inline void __attribute__((always_inline))
93 vhost_log_used_vring(struct virtio_net *dev, struct vhost_virtqueue *vq,
94 uint64_t offset, uint64_t len)
96 vhost_log_write(dev, vq->log_guest_addr + offset, len);
100 is_valid_virt_queue_idx(uint32_t idx, int is_tx, uint32_t qp_nb)
102 return (is_tx ^ (idx & 1)) == 0 && idx < qp_nb * VIRTIO_QNUM;
105 static inline struct vring_desc *__attribute__((always_inline))
106 alloc_copy_ind_table(struct virtio_net *dev, struct vring_desc *desc)
108 struct vring_desc *idesc;
110 uint64_t len, remain = desc->len;
111 uint64_t desc_addr = desc->addr;
113 idesc = rte_malloc(__func__, desc->len, 0);
114 if (unlikely(!idesc))
117 dst = (uint64_t)(uintptr_t)idesc;
121 src = gpa_to_vva(dev, desc_addr, &len);
122 if (unlikely(!src || !len)) {
127 rte_memcpy((void *)(uintptr_t)dst, (void *)(uintptr_t)src, len);
137 static inline void __attribute__((always_inline))
138 free_ind_table(struct vring_desc *idesc)
143 static inline void __attribute__((always_inline))
144 do_flush_shadow_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq,
145 uint16_t to, uint16_t from, uint16_t size)
147 rte_memcpy(&vq->used->ring[to],
148 &vq->shadow_used_ring[from],
149 size * sizeof(struct vring_used_elem));
150 vhost_log_used_vring(dev, vq,
151 offsetof(struct vring_used, ring[to]),
152 size * sizeof(struct vring_used_elem));
155 static inline void __attribute__((always_inline))
156 flush_shadow_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq)
158 uint16_t used_idx = vq->last_used_idx & (vq->size - 1);
160 if (used_idx + vq->shadow_used_idx <= vq->size) {
161 do_flush_shadow_used_ring(dev, vq, used_idx, 0,
162 vq->shadow_used_idx);
166 /* update used ring interval [used_idx, vq->size] */
167 size = vq->size - used_idx;
168 do_flush_shadow_used_ring(dev, vq, used_idx, 0, size);
170 /* update the left half used ring interval [0, left_size] */
171 do_flush_shadow_used_ring(dev, vq, 0, size,
172 vq->shadow_used_idx - size);
174 vq->last_used_idx += vq->shadow_used_idx;
178 *(volatile uint16_t *)&vq->used->idx += vq->shadow_used_idx;
179 vhost_log_used_vring(dev, vq, offsetof(struct vring_used, idx),
180 sizeof(vq->used->idx));
183 static inline void __attribute__((always_inline))
184 update_shadow_used_ring(struct vhost_virtqueue *vq,
185 uint16_t desc_idx, uint16_t len)
187 uint16_t i = vq->shadow_used_idx++;
189 vq->shadow_used_ring[i].id = desc_idx;
190 vq->shadow_used_ring[i].len = len;
194 virtio_enqueue_offload(struct rte_mbuf *m_buf, struct virtio_net_hdr *net_hdr)
196 uint64_t csum_l4 = m_buf->ol_flags & PKT_TX_L4_MASK;
198 if (m_buf->ol_flags & PKT_TX_TCP_SEG)
199 csum_l4 |= PKT_TX_TCP_CKSUM;
202 net_hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
203 net_hdr->csum_start = m_buf->l2_len + m_buf->l3_len;
206 case PKT_TX_TCP_CKSUM:
207 net_hdr->csum_offset = (offsetof(struct tcp_hdr,
210 case PKT_TX_UDP_CKSUM:
211 net_hdr->csum_offset = (offsetof(struct udp_hdr,
214 case PKT_TX_SCTP_CKSUM:
215 net_hdr->csum_offset = (offsetof(struct sctp_hdr,
221 /* IP cksum verification cannot be bypassed, then calculate here */
222 if (m_buf->ol_flags & PKT_TX_IP_CKSUM) {
223 struct ipv4_hdr *ipv4_hdr;
225 ipv4_hdr = rte_pktmbuf_mtod_offset(m_buf, struct ipv4_hdr *,
227 ipv4_hdr->hdr_checksum = rte_ipv4_cksum(ipv4_hdr);
230 if (m_buf->ol_flags & PKT_TX_TCP_SEG) {
231 if (m_buf->ol_flags & PKT_TX_IPV4)
232 net_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
234 net_hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
235 net_hdr->gso_size = m_buf->tso_segsz;
236 net_hdr->hdr_len = m_buf->l2_len + m_buf->l3_len
242 copy_virtio_net_hdr(struct virtio_net *dev, uint64_t desc_addr,
243 struct virtio_net_hdr_mrg_rxbuf hdr)
245 if (dev->vhost_hlen == sizeof(struct virtio_net_hdr_mrg_rxbuf))
246 *(struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)desc_addr = hdr;
248 *(struct virtio_net_hdr *)(uintptr_t)desc_addr = hdr.hdr;
251 static inline int __attribute__((always_inline))
252 copy_mbuf_to_desc(struct virtio_net *dev, struct vring_desc *descs,
253 struct rte_mbuf *m, uint16_t desc_idx, uint32_t size)
255 uint32_t desc_avail, desc_offset;
256 uint32_t mbuf_avail, mbuf_offset;
258 uint64_t desc_chunck_len;
259 struct vring_desc *desc;
260 uint64_t desc_addr, desc_gaddr;
261 struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0};
262 /* A counter to avoid desc dead loop chain */
263 uint16_t nr_desc = 1;
265 desc = &descs[desc_idx];
266 desc_chunck_len = desc->len;
267 desc_gaddr = desc->addr;
268 desc_addr = gpa_to_vva(dev, desc_gaddr, &desc_chunck_len);
270 * Checking of 'desc_addr' placed outside of 'unlikely' macro to avoid
271 * performance issue with some versions of gcc (4.8.4 and 5.3.0) which
272 * otherwise stores offset on the stack instead of in a register.
274 if (unlikely(desc->len < dev->vhost_hlen) || !desc_addr)
277 rte_prefetch0((void *)(uintptr_t)desc_addr);
279 virtio_enqueue_offload(m, &virtio_hdr.hdr);
280 if (likely(desc_chunck_len >= dev->vhost_hlen)) {
281 copy_virtio_net_hdr(dev, desc_addr, virtio_hdr);
283 virtio_enqueue_offload(m,
284 (struct virtio_net_hdr *)(uintptr_t)desc_addr);
285 PRINT_PACKET(dev, (uintptr_t)desc_addr, dev->vhost_hlen, 0);
287 uint64_t remain = dev->vhost_hlen;
289 uint64_t src = (uint64_t)(uintptr_t)&virtio_hdr, dst;
290 uint64_t guest_addr = desc_gaddr;
294 dst = gpa_to_vva(dev, guest_addr, &len);
295 if (unlikely(!dst || !len))
298 rte_memcpy((void *)(uintptr_t)dst,
299 (void *)(uintptr_t)src, len);
301 PRINT_PACKET(dev, (uintptr_t)dst, len, 0);
308 vhost_log_write(dev, desc_gaddr, dev->vhost_hlen);
310 desc_avail = desc->len - dev->vhost_hlen;
311 if (unlikely(desc_chunck_len < dev->vhost_hlen)) {
312 desc_chunck_len = desc_avail;
313 desc_gaddr += dev->vhost_hlen;
314 desc_addr = gpa_to_vva(dev,
317 if (unlikely(!desc_addr))
322 desc_offset = dev->vhost_hlen;
323 desc_chunck_len -= dev->vhost_hlen;
326 mbuf_avail = rte_pktmbuf_data_len(m);
328 while (mbuf_avail != 0 || m->next != NULL) {
329 /* done with current mbuf, fetch next */
330 if (mbuf_avail == 0) {
334 mbuf_avail = rte_pktmbuf_data_len(m);
337 /* done with current desc buf, fetch next */
338 if (desc_avail == 0) {
339 if ((desc->flags & VRING_DESC_F_NEXT) == 0) {
340 /* Room in vring buffer is not enough */
343 if (unlikely(desc->next >= size || ++nr_desc > size))
346 desc = &descs[desc->next];
347 desc_chunck_len = desc->len;
348 desc_gaddr = desc->addr;
349 desc_addr = gpa_to_vva(dev,
350 desc_gaddr, &desc_chunck_len);
351 if (unlikely(!desc_addr))
355 desc_avail = desc->len;
356 } else if (unlikely(desc_chunck_len == 0)) {
357 desc_chunck_len = desc_avail;
358 desc_gaddr += desc_offset;
359 desc_addr = gpa_to_vva(dev,
360 desc_gaddr, &desc_chunck_len);
361 if (unlikely(!desc_addr))
367 cpy_len = RTE_MIN(desc_avail, mbuf_avail);
368 rte_memcpy((void *)((uintptr_t)(desc_addr + desc_offset)),
369 rte_pktmbuf_mtod_offset(m, void *, mbuf_offset),
371 vhost_log_write(dev, desc_gaddr + desc_offset, cpy_len);
372 PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset),
375 mbuf_avail -= cpy_len;
376 mbuf_offset += cpy_len;
377 desc_avail -= cpy_len;
378 desc_offset += cpy_len;
379 desc_chunck_len -= cpy_len;
386 * This function adds buffers to the virtio devices RX virtqueue. Buffers can
387 * be received from the physical port or from another virtio device. A packet
388 * count is returned to indicate the number of packets that are succesfully
389 * added to the RX queue. This function works when the mbuf is scattered, but
390 * it doesn't support the mergeable feature.
392 static inline uint32_t __attribute__((always_inline))
393 virtio_dev_rx(struct virtio_net *dev, uint16_t queue_id,
394 struct rte_mbuf **pkts, uint32_t count)
396 struct vhost_virtqueue *vq;
397 uint16_t avail_idx, free_entries, start_idx;
398 uint16_t desc_indexes[MAX_PKT_BURST];
399 struct vring_desc *descs;
404 LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__);
405 if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->virt_qp_nb))) {
406 RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
407 dev->vid, __func__, queue_id);
411 vq = dev->virtqueue[queue_id];
413 rte_spinlock_lock(&vq->access_lock);
415 if (unlikely(vq->enabled == 0))
416 goto out_access_unlock;
418 avail_idx = *((volatile uint16_t *)&vq->avail->idx);
419 start_idx = vq->last_used_idx;
420 free_entries = avail_idx - start_idx;
421 count = RTE_MIN(count, free_entries);
422 count = RTE_MIN(count, (uint32_t)MAX_PKT_BURST);
424 goto out_access_unlock;
426 LOG_DEBUG(VHOST_DATA, "(%d) start_idx %d | end_idx %d\n",
427 dev->vid, start_idx, start_idx + count);
429 /* Retrieve all of the desc indexes first to avoid caching issues. */
430 rte_prefetch0(&vq->avail->ring[start_idx & (vq->size - 1)]);
431 for (i = 0; i < count; i++) {
432 used_idx = (start_idx + i) & (vq->size - 1);
433 desc_indexes[i] = vq->avail->ring[used_idx];
434 vq->used->ring[used_idx].id = desc_indexes[i];
435 vq->used->ring[used_idx].len = pkts[i]->pkt_len +
437 vhost_log_used_vring(dev, vq,
438 offsetof(struct vring_used, ring[used_idx]),
439 sizeof(vq->used->ring[used_idx]));
442 rte_prefetch0(&vq->desc[desc_indexes[0]]);
443 for (i = 0; i < count; i++) {
444 struct vring_desc *idesc = NULL;
445 uint16_t desc_idx = desc_indexes[i];
448 if (vq->desc[desc_idx].flags & VRING_DESC_F_INDIRECT) {
449 dlen = vq->desc[desc_idx].len;
450 descs = (struct vring_desc *)(uintptr_t)gpa_to_vva(dev,
451 vq->desc[desc_idx].addr, &dlen);
452 if (unlikely(!descs)) {
457 if (unlikely(dlen < vq->desc[desc_idx].len)) {
459 * The indirect desc table is not contiguous
460 * in process VA space, we have to copy it.
462 idesc = alloc_copy_ind_table(dev,
463 &vq->desc[desc_idx]);
464 if (unlikely(!idesc))
471 sz = vq->desc[desc_idx].len / sizeof(*descs);
477 err = copy_mbuf_to_desc(dev, descs, pkts[i], desc_idx, sz);
479 used_idx = (start_idx + i) & (vq->size - 1);
480 vq->used->ring[used_idx].len = dev->vhost_hlen;
481 vhost_log_used_vring(dev, vq,
482 offsetof(struct vring_used, ring[used_idx]),
483 sizeof(vq->used->ring[used_idx]));
487 rte_prefetch0(&vq->desc[desc_indexes[i+1]]);
489 if (unlikely(!!idesc))
490 free_ind_table(idesc);
495 *(volatile uint16_t *)&vq->used->idx += count;
496 vq->last_used_idx += count;
497 vhost_log_used_vring(dev, vq,
498 offsetof(struct vring_used, idx),
499 sizeof(vq->used->idx));
501 /* flush used->idx update before we read avail->flags. */
504 /* Kick the guest if necessary. */
505 if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
506 && (vq->callfd >= 0))
507 eventfd_write(vq->callfd, (eventfd_t)1);
510 rte_spinlock_unlock(&vq->access_lock);
515 static inline int __attribute__((always_inline))
516 fill_vec_buf(struct virtio_net *dev, struct vhost_virtqueue *vq,
517 uint32_t avail_idx, uint32_t *vec_idx,
518 struct buf_vector *buf_vec, uint16_t *desc_chain_head,
519 uint16_t *desc_chain_len)
521 uint16_t idx = vq->avail->ring[avail_idx & (vq->size - 1)];
522 uint32_t vec_id = *vec_idx;
525 struct vring_desc *descs = vq->desc;
526 struct vring_desc *idesc = NULL;
528 *desc_chain_head = idx;
530 if (vq->desc[idx].flags & VRING_DESC_F_INDIRECT) {
531 dlen = vq->desc[idx].len;
532 descs = (struct vring_desc *)(uintptr_t)
533 gpa_to_vva(dev, vq->desc[idx].addr,
535 if (unlikely(!descs))
538 if (unlikely(dlen < vq->desc[idx].len)) {
540 * The indirect desc table is not contiguous
541 * in process VA space, we have to copy it.
543 idesc = alloc_copy_ind_table(dev, &vq->desc[idx]);
544 if (unlikely(!idesc))
554 if (unlikely(vec_id >= BUF_VECTOR_MAX || idx >= vq->size)) {
555 free_ind_table(idesc);
559 len += descs[idx].len;
560 buf_vec[vec_id].buf_addr = descs[idx].addr;
561 buf_vec[vec_id].buf_len = descs[idx].len;
562 buf_vec[vec_id].desc_idx = idx;
565 if ((descs[idx].flags & VRING_DESC_F_NEXT) == 0)
568 idx = descs[idx].next;
571 *desc_chain_len = len;
574 if (unlikely(!!idesc))
575 free_ind_table(idesc);
581 * Returns -1 on fail, 0 on success
584 reserve_avail_buf_mergeable(struct virtio_net *dev, struct vhost_virtqueue *vq,
585 uint32_t size, struct buf_vector *buf_vec,
586 uint16_t *num_buffers, uint16_t avail_head)
589 uint32_t vec_idx = 0;
592 uint16_t head_idx = 0;
596 cur_idx = vq->last_avail_idx;
599 if (unlikely(cur_idx == avail_head))
602 if (unlikely(fill_vec_buf(dev, vq, cur_idx, &vec_idx, buf_vec,
603 &head_idx, &len) < 0))
605 len = RTE_MIN(len, size);
606 update_shadow_used_ring(vq, head_idx, len);
614 * if we tried all available ring items, and still
615 * can't get enough buf, it means something abnormal
618 if (unlikely(tries >= vq->size))
625 static inline int __attribute__((always_inline))
626 copy_mbuf_to_desc_mergeable(struct virtio_net *dev, struct rte_mbuf *m,
627 struct buf_vector *buf_vec, uint16_t num_buffers)
629 struct virtio_net_hdr_mrg_rxbuf virtio_hdr = {{0, 0, 0, 0, 0, 0}, 0};
630 struct virtio_net_hdr_mrg_rxbuf *hdr;
631 uint32_t vec_idx = 0;
632 uint64_t desc_addr, desc_gaddr;
633 uint64_t desc_chunck_len;
634 uint32_t mbuf_offset, mbuf_avail;
635 uint32_t desc_offset, desc_avail;
637 uint64_t hdr_addr, hdr_phys_addr;
638 struct rte_mbuf *hdr_mbuf;
640 if (unlikely(m == NULL))
643 desc_chunck_len = buf_vec[vec_idx].buf_len;
644 desc_gaddr = buf_vec[vec_idx].buf_addr;
645 desc_addr = gpa_to_vva(dev, desc_gaddr, &desc_chunck_len);
646 if (buf_vec[vec_idx].buf_len < dev->vhost_hlen ||
651 hdr_addr = desc_addr;
652 if (unlikely(desc_chunck_len < dev->vhost_hlen))
655 hdr = (struct virtio_net_hdr_mrg_rxbuf *)(uintptr_t)hdr_addr;
656 hdr_phys_addr = buf_vec[vec_idx].buf_addr;
657 rte_prefetch0((void *)(uintptr_t)hdr_addr);
659 virtio_hdr.num_buffers = num_buffers;
660 LOG_DEBUG(VHOST_DATA, "(%d) RX: num merge buffers %d\n",
661 dev->vid, num_buffers);
663 desc_avail = buf_vec[vec_idx].buf_len - dev->vhost_hlen;
664 if (unlikely(desc_chunck_len < dev->vhost_hlen)) {
665 desc_chunck_len = desc_avail;
666 desc_gaddr += dev->vhost_hlen;
667 desc_addr = gpa_to_vva(dev,
670 if (unlikely(!desc_addr))
675 desc_offset = dev->vhost_hlen;
676 desc_chunck_len -= dev->vhost_hlen;
680 mbuf_avail = rte_pktmbuf_data_len(m);
682 while (mbuf_avail != 0 || m->next != NULL) {
683 /* done with current desc buf, get the next one */
684 if (desc_avail == 0) {
686 desc_gaddr = buf_vec[vec_idx].buf_addr;
687 desc_chunck_len = buf_vec[vec_idx].buf_len;
688 desc_addr = gpa_to_vva(dev, desc_gaddr,
690 if (unlikely(!desc_addr))
693 /* Prefetch buffer address. */
694 rte_prefetch0((void *)(uintptr_t)desc_addr);
696 desc_avail = buf_vec[vec_idx].buf_len;
697 } else if (unlikely(desc_chunck_len == 0)) {
698 desc_chunck_len = desc_avail;
699 desc_gaddr += desc_offset;
700 desc_addr = gpa_to_vva(dev,
703 if (unlikely(!desc_addr))
709 /* done with current mbuf, get the next one */
710 if (mbuf_avail == 0) {
714 mbuf_avail = rte_pktmbuf_data_len(m);
718 virtio_enqueue_offload(hdr_mbuf, &virtio_hdr.hdr);
719 if (likely(hdr != &virtio_hdr)) {
720 copy_virtio_net_hdr(dev, hdr_addr, virtio_hdr);
723 uint64_t remain = dev->vhost_hlen;
724 uint64_t src = (uint64_t)(uintptr_t)&virtio_hdr;
726 uint64_t guest_addr = hdr_phys_addr;
730 dst = gpa_to_vva(dev, guest_addr, &len);
731 if (unlikely(!dst || !len))
734 rte_memcpy((void *)(uintptr_t)dst,
735 (void *)(uintptr_t)src,
738 PRINT_PACKET(dev, (uintptr_t)dst,
746 vhost_log_write(dev, hdr_phys_addr, dev->vhost_hlen);
747 PRINT_PACKET(dev, (uintptr_t)hdr_addr,
753 cpy_len = RTE_MIN(desc_chunck_len, mbuf_avail);
754 rte_memcpy((void *)((uintptr_t)(desc_addr + desc_offset)),
755 rte_pktmbuf_mtod_offset(m, void *, mbuf_offset),
757 vhost_log_write(dev, desc_gaddr + desc_offset, cpy_len);
758 PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset),
761 mbuf_avail -= cpy_len;
762 mbuf_offset += cpy_len;
763 desc_avail -= cpy_len;
764 desc_offset += cpy_len;
765 desc_chunck_len -= cpy_len;
771 static inline uint32_t __attribute__((always_inline))
772 virtio_dev_merge_rx(struct virtio_net *dev, uint16_t queue_id,
773 struct rte_mbuf **pkts, uint32_t count)
775 struct vhost_virtqueue *vq;
776 uint32_t pkt_idx = 0;
777 uint16_t num_buffers;
778 struct buf_vector buf_vec[BUF_VECTOR_MAX];
781 LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__);
782 if (unlikely(!is_valid_virt_queue_idx(queue_id, 0, dev->virt_qp_nb))) {
783 RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
784 dev->vid, __func__, queue_id);
788 vq = dev->virtqueue[queue_id];
790 rte_spinlock_lock(&vq->access_lock);
792 if (unlikely(vq->enabled == 0))
793 goto out_access_unlock;
795 count = RTE_MIN((uint32_t)MAX_PKT_BURST, count);
797 goto out_access_unlock;
799 rte_prefetch0(&vq->avail->ring[vq->last_avail_idx & (vq->size - 1)]);
801 vq->shadow_used_idx = 0;
802 avail_head = *((volatile uint16_t *)&vq->avail->idx);
803 for (pkt_idx = 0; pkt_idx < count; pkt_idx++) {
804 uint32_t pkt_len = pkts[pkt_idx]->pkt_len + dev->vhost_hlen;
806 if (unlikely(reserve_avail_buf_mergeable(dev, vq,
807 pkt_len, buf_vec, &num_buffers,
809 LOG_DEBUG(VHOST_DATA,
810 "(%d) failed to get enough desc from vring\n",
812 vq->shadow_used_idx -= num_buffers;
816 LOG_DEBUG(VHOST_DATA, "(%d) current index %d | end index %d\n",
817 dev->vid, vq->last_avail_idx,
818 vq->last_avail_idx + num_buffers);
820 if (copy_mbuf_to_desc_mergeable(dev, pkts[pkt_idx],
821 buf_vec, num_buffers) < 0) {
822 vq->shadow_used_idx -= num_buffers;
826 vq->last_avail_idx += num_buffers;
829 if (likely(vq->shadow_used_idx)) {
830 flush_shadow_used_ring(dev, vq);
832 /* flush used->idx update before we read avail->flags. */
835 /* Kick the guest if necessary. */
836 if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
837 && (vq->callfd >= 0))
838 eventfd_write(vq->callfd, (eventfd_t)1);
842 rte_spinlock_unlock(&vq->access_lock);
848 rte_vhost_enqueue_burst(int vid, uint16_t queue_id,
849 struct rte_mbuf **pkts, uint16_t count)
851 struct virtio_net *dev = get_device(vid);
856 if (dev->features & (1 << VIRTIO_NET_F_MRG_RXBUF))
857 return virtio_dev_merge_rx(dev, queue_id, pkts, count);
859 return virtio_dev_rx(dev, queue_id, pkts, count);
863 virtio_net_with_host_offload(struct virtio_net *dev)
866 ((1ULL << VIRTIO_NET_F_CSUM) |
867 (1ULL << VIRTIO_NET_F_HOST_ECN) |
868 (1ULL << VIRTIO_NET_F_HOST_TSO4) |
869 (1ULL << VIRTIO_NET_F_HOST_TSO6) |
870 (1ULL << VIRTIO_NET_F_HOST_UFO)))
877 parse_ethernet(struct rte_mbuf *m, uint16_t *l4_proto, void **l4_hdr)
879 struct ipv4_hdr *ipv4_hdr;
880 struct ipv6_hdr *ipv6_hdr;
882 struct ether_hdr *eth_hdr;
885 eth_hdr = rte_pktmbuf_mtod(m, struct ether_hdr *);
887 m->l2_len = sizeof(struct ether_hdr);
888 ethertype = rte_be_to_cpu_16(eth_hdr->ether_type);
890 if (ethertype == ETHER_TYPE_VLAN) {
891 struct vlan_hdr *vlan_hdr = (struct vlan_hdr *)(eth_hdr + 1);
893 m->l2_len += sizeof(struct vlan_hdr);
894 ethertype = rte_be_to_cpu_16(vlan_hdr->eth_proto);
897 l3_hdr = (char *)eth_hdr + m->l2_len;
900 case ETHER_TYPE_IPv4:
901 ipv4_hdr = (struct ipv4_hdr *)l3_hdr;
902 *l4_proto = ipv4_hdr->next_proto_id;
903 m->l3_len = (ipv4_hdr->version_ihl & 0x0f) * 4;
904 *l4_hdr = (char *)l3_hdr + m->l3_len;
905 m->ol_flags |= PKT_TX_IPV4;
907 case ETHER_TYPE_IPv6:
908 ipv6_hdr = (struct ipv6_hdr *)l3_hdr;
909 *l4_proto = ipv6_hdr->proto;
910 m->l3_len = sizeof(struct ipv6_hdr);
911 *l4_hdr = (char *)l3_hdr + m->l3_len;
912 m->ol_flags |= PKT_TX_IPV6;
922 static inline void __attribute__((always_inline))
923 vhost_dequeue_offload(struct virtio_net_hdr *hdr, struct rte_mbuf *m)
925 uint16_t l4_proto = 0;
927 struct tcp_hdr *tcp_hdr = NULL;
929 if (hdr->flags == 0 && hdr->gso_type == VIRTIO_NET_HDR_GSO_NONE)
932 parse_ethernet(m, &l4_proto, &l4_hdr);
933 if (hdr->flags == VIRTIO_NET_HDR_F_NEEDS_CSUM) {
934 if (hdr->csum_start == (m->l2_len + m->l3_len)) {
935 switch (hdr->csum_offset) {
936 case (offsetof(struct tcp_hdr, cksum)):
937 if (l4_proto == IPPROTO_TCP)
938 m->ol_flags |= PKT_TX_TCP_CKSUM;
940 case (offsetof(struct udp_hdr, dgram_cksum)):
941 if (l4_proto == IPPROTO_UDP)
942 m->ol_flags |= PKT_TX_UDP_CKSUM;
944 case (offsetof(struct sctp_hdr, cksum)):
945 if (l4_proto == IPPROTO_SCTP)
946 m->ol_flags |= PKT_TX_SCTP_CKSUM;
954 if (l4_hdr && hdr->gso_type != VIRTIO_NET_HDR_GSO_NONE) {
955 switch (hdr->gso_type & ~VIRTIO_NET_HDR_GSO_ECN) {
956 case VIRTIO_NET_HDR_GSO_TCPV4:
957 case VIRTIO_NET_HDR_GSO_TCPV6:
958 tcp_hdr = (struct tcp_hdr *)l4_hdr;
959 m->ol_flags |= PKT_TX_TCP_SEG;
960 m->tso_segsz = hdr->gso_size;
961 m->l4_len = (tcp_hdr->data_off & 0xf0) >> 2;
964 RTE_LOG(WARNING, VHOST_DATA,
965 "unsupported gso type %u.\n", hdr->gso_type);
971 #define RARP_PKT_SIZE 64
974 make_rarp_packet(struct rte_mbuf *rarp_mbuf, const struct ether_addr *mac)
976 struct ether_hdr *eth_hdr;
977 struct arp_hdr *rarp;
979 if (rarp_mbuf->buf_len < 64) {
980 RTE_LOG(WARNING, VHOST_DATA,
981 "failed to make RARP; mbuf size too small %u (< %d)\n",
982 rarp_mbuf->buf_len, RARP_PKT_SIZE);
986 /* Ethernet header. */
987 eth_hdr = rte_pktmbuf_mtod_offset(rarp_mbuf, struct ether_hdr *, 0);
988 memset(eth_hdr->d_addr.addr_bytes, 0xff, ETHER_ADDR_LEN);
989 ether_addr_copy(mac, ð_hdr->s_addr);
990 eth_hdr->ether_type = htons(ETHER_TYPE_RARP);
993 rarp = (struct arp_hdr *)(eth_hdr + 1);
994 rarp->arp_hrd = htons(ARP_HRD_ETHER);
995 rarp->arp_pro = htons(ETHER_TYPE_IPv4);
996 rarp->arp_hln = ETHER_ADDR_LEN;
998 rarp->arp_op = htons(ARP_OP_REVREQUEST);
1000 ether_addr_copy(mac, &rarp->arp_data.arp_sha);
1001 ether_addr_copy(mac, &rarp->arp_data.arp_tha);
1002 memset(&rarp->arp_data.arp_sip, 0x00, 4);
1003 memset(&rarp->arp_data.arp_tip, 0x00, 4);
1005 rarp_mbuf->pkt_len = rarp_mbuf->data_len = RARP_PKT_SIZE;
1010 static inline void __attribute__((always_inline))
1011 put_zmbuf(struct zcopy_mbuf *zmbuf)
1016 static inline int __attribute__((always_inline))
1017 copy_desc_to_mbuf(struct virtio_net *dev, struct vring_desc *descs,
1018 uint16_t max_desc, struct rte_mbuf *m, uint16_t desc_idx,
1019 struct rte_mempool *mbuf_pool)
1021 struct vring_desc *desc;
1022 uint64_t desc_addr, desc_gaddr;
1023 uint32_t desc_avail, desc_offset;
1024 uint32_t mbuf_avail, mbuf_offset;
1026 uint64_t desc_chunck_len;
1027 struct rte_mbuf *cur = m, *prev = m;
1028 struct virtio_net_hdr tmp_hdr;
1029 struct virtio_net_hdr *hdr = NULL;
1030 /* A counter to avoid desc dead loop chain */
1031 uint32_t nr_desc = 1;
1033 desc = &descs[desc_idx];
1034 if (unlikely((desc->len < dev->vhost_hlen)) ||
1035 (desc->flags & VRING_DESC_F_INDIRECT))
1038 desc_chunck_len = desc->len;
1039 desc_gaddr = desc->addr;
1040 desc_addr = gpa_to_vva(dev, desc_gaddr, &desc_chunck_len);
1041 if (unlikely(!desc_addr))
1044 if (virtio_net_with_host_offload(dev)) {
1045 if (unlikely(desc_chunck_len < sizeof(struct virtio_net_hdr))) {
1046 uint64_t len = desc_chunck_len;
1047 uint64_t remain = sizeof(struct virtio_net_hdr);
1048 uint64_t src = desc_addr;
1049 uint64_t dst = (uint64_t)(uintptr_t)&tmp_hdr;
1050 uint64_t guest_addr = desc_gaddr;
1053 * No luck, the virtio-net header doesn't fit
1054 * in a contiguous virtual area.
1058 src = gpa_to_vva(dev, guest_addr, &len);
1059 if (unlikely(!src || !len))
1062 rte_memcpy((void *)(uintptr_t)dst,
1063 (void *)(uintptr_t)src, len);
1072 hdr = (struct virtio_net_hdr *)((uintptr_t)desc_addr);
1078 * A virtio driver normally uses at least 2 desc buffers
1079 * for Tx: the first for storing the header, and others
1080 * for storing the data.
1082 if (likely((desc->len == dev->vhost_hlen) &&
1083 (desc->flags & VRING_DESC_F_NEXT) != 0)) {
1084 desc = &descs[desc->next];
1085 if (unlikely(desc->flags & VRING_DESC_F_INDIRECT))
1088 desc_chunck_len = desc->len;
1089 desc_gaddr = desc->addr;
1090 desc_addr = gpa_to_vva(dev, desc_gaddr, &desc_chunck_len);
1091 if (unlikely(!desc_addr))
1095 desc_avail = desc->len;
1098 desc_avail = desc->len - dev->vhost_hlen;
1100 if (unlikely(desc_chunck_len < dev->vhost_hlen)) {
1101 desc_chunck_len = desc_avail;
1102 desc_gaddr += dev->vhost_hlen;
1103 desc_addr = gpa_to_vva(dev,
1106 if (unlikely(!desc_addr))
1111 desc_offset = dev->vhost_hlen;
1112 desc_chunck_len -= dev->vhost_hlen;
1116 rte_prefetch0((void *)(uintptr_t)(desc_addr + desc_offset));
1118 PRINT_PACKET(dev, (uintptr_t)(desc_addr + desc_offset),
1119 desc_chunck_len, 0);
1122 mbuf_avail = m->buf_len - RTE_PKTMBUF_HEADROOM;
1126 cpy_len = RTE_MIN(desc_chunck_len, mbuf_avail);
1129 * A desc buf might across two host physical pages that are
1130 * not continuous. In such case (gpa_to_hpa returns 0), data
1131 * will be copied even though zero copy is enabled.
1133 if (unlikely(dev->dequeue_zero_copy && (hpa = gpa_to_hpa(dev,
1134 desc_gaddr + desc_offset, cpy_len)))) {
1135 cur->data_len = cpy_len;
1137 cur->buf_addr = (void *)(uintptr_t)(desc_gaddr
1139 cur->buf_physaddr = hpa;
1142 * In zero copy mode, one mbuf can only reference data
1143 * for one or partial of one desc buff.
1145 mbuf_avail = cpy_len;
1147 rte_memcpy(rte_pktmbuf_mtod_offset(cur, void *,
1149 (void *)((uintptr_t)(desc_addr + desc_offset)),
1153 mbuf_avail -= cpy_len;
1154 mbuf_offset += cpy_len;
1155 desc_avail -= cpy_len;
1156 desc_chunck_len -= cpy_len;
1157 desc_offset += cpy_len;
1159 /* This desc reaches to its end, get the next one */
1160 if (desc_avail == 0) {
1161 if ((desc->flags & VRING_DESC_F_NEXT) == 0)
1164 if (unlikely(desc->next >= max_desc ||
1165 ++nr_desc > max_desc))
1167 desc = &descs[desc->next];
1168 if (unlikely(desc->flags & VRING_DESC_F_INDIRECT))
1171 desc_chunck_len = desc->len;
1172 desc_gaddr = desc->addr;
1173 desc_addr = gpa_to_vva(dev, desc_gaddr,
1175 if (unlikely(!desc_addr))
1178 rte_prefetch0((void *)(uintptr_t)desc_addr);
1181 desc_avail = desc->len;
1183 PRINT_PACKET(dev, (uintptr_t)desc_addr,
1184 desc_chunck_len, 0);
1185 } else if (unlikely(desc_chunck_len == 0)) {
1186 desc_chunck_len = desc_avail;
1187 desc_gaddr += desc_offset;
1188 desc_addr = gpa_to_vva(dev,
1191 if (unlikely(!desc_addr))
1196 PRINT_PACKET(dev, (uintptr_t)desc_addr,
1197 desc_chunck_len, 0);
1201 * This mbuf reaches to its end, get a new one
1202 * to hold more data.
1204 if (mbuf_avail == 0) {
1205 cur = rte_pktmbuf_alloc(mbuf_pool);
1206 if (unlikely(cur == NULL)) {
1207 RTE_LOG(ERR, VHOST_DATA, "Failed to "
1208 "allocate memory for mbuf.\n");
1211 if (unlikely(dev->dequeue_zero_copy))
1212 rte_mbuf_refcnt_update(cur, 1);
1215 prev->data_len = mbuf_offset;
1217 m->pkt_len += mbuf_offset;
1221 mbuf_avail = cur->buf_len - RTE_PKTMBUF_HEADROOM;
1225 prev->data_len = mbuf_offset;
1226 m->pkt_len += mbuf_offset;
1229 vhost_dequeue_offload(hdr, m);
1234 static inline void __attribute__((always_inline))
1235 update_used_ring(struct virtio_net *dev, struct vhost_virtqueue *vq,
1236 uint32_t used_idx, uint32_t desc_idx)
1238 vq->used->ring[used_idx].id = desc_idx;
1239 vq->used->ring[used_idx].len = 0;
1240 vhost_log_used_vring(dev, vq,
1241 offsetof(struct vring_used, ring[used_idx]),
1242 sizeof(vq->used->ring[used_idx]));
1245 static inline void __attribute__((always_inline))
1246 update_used_idx(struct virtio_net *dev, struct vhost_virtqueue *vq,
1249 if (unlikely(count == 0))
1255 vq->used->idx += count;
1256 vhost_log_used_vring(dev, vq, offsetof(struct vring_used, idx),
1257 sizeof(vq->used->idx));
1259 /* Kick guest if required. */
1260 if (!(vq->avail->flags & VRING_AVAIL_F_NO_INTERRUPT)
1261 && (vq->callfd >= 0))
1262 eventfd_write(vq->callfd, (eventfd_t)1);
1265 static inline struct zcopy_mbuf *__attribute__((always_inline))
1266 get_zmbuf(struct vhost_virtqueue *vq)
1272 /* search [last_zmbuf_idx, zmbuf_size) */
1273 i = vq->last_zmbuf_idx;
1274 last = vq->zmbuf_size;
1277 for (; i < last; i++) {
1278 if (vq->zmbufs[i].in_use == 0) {
1279 vq->last_zmbuf_idx = i + 1;
1280 vq->zmbufs[i].in_use = 1;
1281 return &vq->zmbufs[i];
1287 /* search [0, last_zmbuf_idx) */
1289 last = vq->last_zmbuf_idx;
1296 static inline bool __attribute__((always_inline))
1297 mbuf_is_consumed(struct rte_mbuf *m)
1300 if (rte_mbuf_refcnt_read(m) > 1)
1308 static inline void __attribute__((always_inline))
1309 restore_mbuf(struct rte_mbuf *m)
1311 uint32_t mbuf_size, priv_size;
1314 priv_size = rte_pktmbuf_priv_size(m->pool);
1315 mbuf_size = sizeof(struct rte_mbuf) + priv_size;
1316 /* start of buffer is after mbuf structure and priv data */
1318 m->buf_addr = (char *)m + mbuf_size;
1319 m->buf_physaddr = rte_mempool_virt2phy(NULL, m) + mbuf_size;
1325 rte_vhost_dequeue_burst(int vid, uint16_t queue_id,
1326 struct rte_mempool *mbuf_pool, struct rte_mbuf **pkts, uint16_t count)
1328 struct virtio_net *dev;
1329 struct rte_mbuf *rarp_mbuf = NULL;
1330 struct vhost_virtqueue *vq;
1331 uint32_t desc_indexes[MAX_PKT_BURST];
1334 uint16_t free_entries;
1337 dev = get_device(vid);
1341 if (unlikely(!is_valid_virt_queue_idx(queue_id, 1, dev->virt_qp_nb))) {
1342 RTE_LOG(ERR, VHOST_DATA, "(%d) %s: invalid virtqueue idx %d.\n",
1343 dev->vid, __func__, queue_id);
1347 vq = dev->virtqueue[queue_id];
1349 if (unlikely(rte_spinlock_trylock(&vq->access_lock) == 0))
1352 if (unlikely(vq->enabled == 0))
1353 goto out_access_unlock;
1355 if (unlikely(dev->dequeue_zero_copy)) {
1356 struct zcopy_mbuf *zmbuf, *next;
1359 for (zmbuf = TAILQ_FIRST(&vq->zmbuf_list);
1360 zmbuf != NULL; zmbuf = next) {
1361 next = TAILQ_NEXT(zmbuf, next);
1363 if (mbuf_is_consumed(zmbuf->mbuf)) {
1364 used_idx = vq->last_used_idx++ & (vq->size - 1);
1365 update_used_ring(dev, vq, used_idx,
1369 TAILQ_REMOVE(&vq->zmbuf_list, zmbuf, next);
1370 restore_mbuf(zmbuf->mbuf);
1371 rte_pktmbuf_free(zmbuf->mbuf);
1377 update_used_idx(dev, vq, nr_updated);
1381 * Construct a RARP broadcast packet, and inject it to the "pkts"
1382 * array, to looks like that guest actually send such packet.
1384 * Check user_send_rarp() for more information.
1386 * broadcast_rarp shares a cacheline in the virtio_net structure
1387 * with some fields that are accessed during enqueue and
1388 * rte_atomic16_cmpset() causes a write if using cmpxchg. This could
1389 * result in false sharing between enqueue and dequeue.
1391 * Prevent unnecessary false sharing by reading broadcast_rarp first
1392 * and only performing cmpset if the read indicates it is likely to
1396 if (unlikely(rte_atomic16_read(&dev->broadcast_rarp) &&
1397 rte_atomic16_cmpset((volatile uint16_t *)
1398 &dev->broadcast_rarp.cnt, 1, 0))) {
1400 rarp_mbuf = rte_pktmbuf_alloc(mbuf_pool);
1401 if (rarp_mbuf == NULL) {
1402 RTE_LOG(ERR, VHOST_DATA,
1403 "Failed to allocate memory for mbuf.\n");
1404 goto out_access_unlock;
1407 if (make_rarp_packet(rarp_mbuf, &dev->mac)) {
1408 rte_pktmbuf_free(rarp_mbuf);
1415 free_entries = *((volatile uint16_t *)&vq->avail->idx) -
1417 if (free_entries == 0)
1418 goto out_access_unlock;
1420 LOG_DEBUG(VHOST_DATA, "(%d) %s\n", dev->vid, __func__);
1422 /* Prefetch available and used ring */
1423 avail_idx = vq->last_avail_idx & (vq->size - 1);
1424 used_idx = vq->last_used_idx & (vq->size - 1);
1425 rte_prefetch0(&vq->avail->ring[avail_idx]);
1426 rte_prefetch0(&vq->used->ring[used_idx]);
1428 count = RTE_MIN(count, MAX_PKT_BURST);
1429 count = RTE_MIN(count, free_entries);
1430 LOG_DEBUG(VHOST_DATA, "(%d) about to dequeue %u buffers\n",
1433 /* Retrieve all of the head indexes first to avoid caching issues. */
1434 for (i = 0; i < count; i++) {
1435 avail_idx = (vq->last_avail_idx + i) & (vq->size - 1);
1436 used_idx = (vq->last_used_idx + i) & (vq->size - 1);
1437 desc_indexes[i] = vq->avail->ring[avail_idx];
1439 if (likely(dev->dequeue_zero_copy == 0))
1440 update_used_ring(dev, vq, used_idx, desc_indexes[i]);
1443 /* Prefetch descriptor index. */
1444 rte_prefetch0(&vq->desc[desc_indexes[0]]);
1445 for (i = 0; i < count; i++) {
1446 struct vring_desc *desc, *idesc = NULL;
1451 if (likely(i + 1 < count))
1452 rte_prefetch0(&vq->desc[desc_indexes[i + 1]]);
1454 if (vq->desc[desc_indexes[i]].flags & VRING_DESC_F_INDIRECT) {
1455 dlen = vq->desc[desc_indexes[i]].len;
1456 desc = (struct vring_desc *)(uintptr_t)gpa_to_vva(dev,
1457 vq->desc[desc_indexes[i]].addr,
1459 if (unlikely(!desc))
1462 if (unlikely(dlen < vq->desc[desc_indexes[i]].len)) {
1464 * The indirect desc table is not contiguous
1465 * in process VA space, we have to copy it.
1467 idesc = alloc_copy_ind_table(dev,
1468 &vq->desc[desc_indexes[i]]);
1469 if (unlikely(!idesc))
1475 rte_prefetch0(desc);
1476 sz = vq->desc[desc_indexes[i]].len / sizeof(*desc);
1481 idx = desc_indexes[i];
1484 pkts[i] = rte_pktmbuf_alloc(mbuf_pool);
1485 if (unlikely(pkts[i] == NULL)) {
1486 RTE_LOG(ERR, VHOST_DATA,
1487 "Failed to allocate memory for mbuf.\n");
1488 free_ind_table(idesc);
1492 err = copy_desc_to_mbuf(dev, desc, sz, pkts[i], idx, mbuf_pool);
1493 if (unlikely(err)) {
1494 rte_pktmbuf_free(pkts[i]);
1495 free_ind_table(idesc);
1499 if (unlikely(dev->dequeue_zero_copy)) {
1500 struct zcopy_mbuf *zmbuf;
1502 zmbuf = get_zmbuf(vq);
1504 rte_pktmbuf_free(pkts[i]);
1505 free_ind_table(idesc);
1508 zmbuf->mbuf = pkts[i];
1509 zmbuf->desc_idx = desc_indexes[i];
1512 * Pin lock the mbuf; we will check later to see
1513 * whether the mbuf is freed (when we are the last
1514 * user) or not. If that's the case, we then could
1515 * update the used ring safely.
1517 rte_mbuf_refcnt_update(pkts[i], 1);
1520 TAILQ_INSERT_TAIL(&vq->zmbuf_list, zmbuf, next);
1523 if (unlikely(!!idesc))
1524 free_ind_table(idesc);
1526 vq->last_avail_idx += i;
1528 if (likely(dev->dequeue_zero_copy == 0)) {
1529 vq->last_used_idx += i;
1530 update_used_idx(dev, vq, i);
1534 rte_spinlock_unlock(&vq->access_lock);
1536 if (unlikely(rarp_mbuf != NULL)) {
1538 * Inject it to the head of "pkts" array, so that switch's mac
1539 * learning table will get updated first.
1541 memmove(&pkts[1], pkts, i * sizeof(struct rte_mbuf *));
1542 pkts[0] = rarp_mbuf;