2 *------------------------------------------------------------------
3 * Copyright (c) 2016 Cisco and/or its affiliates.
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at:
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *------------------------------------------------------------------
18 #include <sys/types.h>
22 #include <vlib/vlib.h>
23 #include <vlib/unix/unix.h>
24 #include <vnet/vnet.h>
25 #include <vnet/ethernet/ethernet.h>
26 #include <vnet/gso/hdr_offset_parser.h>
27 #include <vnet/ip/ip4_packet.h>
28 #include <vnet/ip/ip6_packet.h>
29 #include <vnet/tcp/tcp_packet.h>
30 #include <vnet/udp/udp_packet.h>
31 #include <vnet/devices/virtio/virtio.h>
33 #define foreach_virtio_tx_func_error \
34 _(NO_FREE_SLOTS, "no free tx slots") \
35 _(TRUNC_PACKET, "packet > buffer size -- truncated in tx ring") \
36 _(PENDING_MSGS, "pending msgs in tx ring") \
37 _(INDIRECT_DESC_ALLOC_FAILED, "indirect descriptor allocation failed - packet drop") \
38 _(OUT_OF_ORDER, "out-of-order buffers in used ring") \
39 _(GSO_PACKET_DROP, "gso disabled on itf -- gso packet drop") \
40 _(CSUM_OFFLOAD_PACKET_DROP, "checksum offload disabled on itf -- csum offload packet drop")
44 #define _(f,s) VIRTIO_TX_ERROR_##f,
45 foreach_virtio_tx_func_error
48 } virtio_tx_func_error_t;
50 static char *virtio_tx_func_error_strings[] = {
52 foreach_virtio_tx_func_error
57 format_virtio_device (u8 * s, va_list * args)
59 u32 dev_instance = va_arg (*args, u32);
60 int verbose = va_arg (*args, int);
61 u32 indent = format_get_indent (s);
63 s = format (s, "VIRTIO interface");
66 s = format (s, "\n%U instance %u", format_white_space, indent + 2,
73 format_virtio_tx_trace (u8 * s, va_list * args)
75 s = format (s, "Unimplemented...");
79 static_always_inline void
80 virtio_interface_drop_inline (vlib_main_t * vm, uword node_index,
82 virtio_tx_func_error_t error)
84 vlib_error_count (vm, node_index, error, n);
85 vlib_buffer_free (vm, buffers, n);
88 static_always_inline void
89 virtio_memset_ring_u32 (u32 * ring, u32 start, u32 ring_size, u32 n_buffers)
91 ASSERT (n_buffers <= ring_size);
93 if (PREDICT_TRUE (start + n_buffers <= ring_size))
95 clib_memset_u32 (ring + start, ~0, n_buffers);
99 clib_memset_u32 (ring + start, ~0, ring_size - start);
100 clib_memset_u32 (ring, ~0, n_buffers - (ring_size - start));
104 static_always_inline void
105 virtio_free_used_device_desc (vlib_main_t * vm, virtio_vring_t * vring,
108 u16 used = vring->desc_in_use;
109 u16 sz = vring->size;
111 u16 last = vring->last_used_idx;
112 u16 n_left = vring->used->idx - last;
113 u16 out_of_order_count = 0;
120 struct vring_used_elem *e = &vring->used->ring[last & mask];
122 slot = n_buffers = e->id;
124 while (e->id == (n_buffers & mask))
129 struct vring_desc *d = &vring->desc[e->id];
131 while (d->flags & VRING_DESC_F_NEXT)
135 d = &vring->desc[next];
139 e = &vring->used->ring[last & mask];
141 vlib_buffer_free_from_ring (vm, vring->buffers, slot,
142 sz, (n_buffers - slot));
143 virtio_memset_ring_u32 (vring->buffers, slot, sz, (n_buffers - slot));
144 used -= (n_buffers - slot);
148 vlib_buffer_free (vm, &vring->buffers[e->id], 1);
149 vring->buffers[e->id] = ~0;
153 out_of_order_count++;
154 vring->flags |= VRING_TX_OUT_OF_ORDER;
159 * Some vhost-backends give buffers back in out-of-order fashion in used ring.
160 * It impacts the overall virtio-performance.
162 if (out_of_order_count)
163 vlib_error_count (vm, node_index, VIRTIO_TX_ERROR_OUT_OF_ORDER,
166 vring->desc_in_use = used;
167 vring->last_used_idx = last;
170 static_always_inline void
171 set_checksum_offsets (vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr,
174 if (b->flags & VNET_BUFFER_F_IS_IP4)
177 generic_header_offset_t gho = { 0 };
178 vnet_generic_header_offset_parser (b, &gho, is_l2, 1 /* ip4 */ ,
180 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
181 hdr->csum_start = gho.l4_hdr_offset; // 0x22;
182 if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
184 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
186 else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)
188 hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
192 * virtio devices do not support IP4 checksum offload. So driver takes care
193 * of it while doing tx.
196 (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
197 if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM)
198 ip4->checksum = ip4_header_checksum (ip4);
200 else if (b->flags & VNET_BUFFER_F_IS_IP6)
202 generic_header_offset_t gho = { 0 };
203 vnet_generic_header_offset_parser (b, &gho, is_l2, 0 /* ip4 */ ,
205 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
206 hdr->csum_start = gho.l4_hdr_offset; // 0x36;
207 if (b->flags & VNET_BUFFER_F_OFFLOAD_TCP_CKSUM)
209 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
211 else if (b->flags & VNET_BUFFER_F_OFFLOAD_UDP_CKSUM)
213 hdr->csum_offset = STRUCT_OFFSET_OF (udp_header_t, checksum);
218 static_always_inline void
219 set_gso_offsets (vlib_buffer_t * b, struct virtio_net_hdr_v1 *hdr, int is_l2)
221 if (b->flags & VNET_BUFFER_F_IS_IP4)
224 generic_header_offset_t gho = { 0 };
225 vnet_generic_header_offset_parser (b, &gho, is_l2, 1 /* ip4 */ ,
227 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
228 hdr->gso_size = vnet_buffer2 (b)->gso_size;
229 hdr->hdr_len = gho.hdr_sz;
230 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
231 hdr->csum_start = gho.l4_hdr_offset; // 0x22;
232 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
234 (ip4_header_t *) (vlib_buffer_get_current (b) + gho.l3_hdr_offset);
236 * virtio devices do not support IP4 checksum offload. So driver takes care
237 * of it while doing tx.
239 if (b->flags & VNET_BUFFER_F_OFFLOAD_IP_CKSUM)
240 ip4->checksum = ip4_header_checksum (ip4);
242 else if (b->flags & VNET_BUFFER_F_IS_IP6)
244 generic_header_offset_t gho = { 0 };
245 vnet_generic_header_offset_parser (b, &gho, is_l2, 0 /* ip4 */ ,
247 hdr->gso_type = VIRTIO_NET_HDR_GSO_TCPV6;
248 hdr->gso_size = vnet_buffer2 (b)->gso_size;
249 hdr->hdr_len = gho.hdr_sz;
250 hdr->flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
251 hdr->csum_start = gho.l4_hdr_offset; // 0x36;
252 hdr->csum_offset = STRUCT_OFFSET_OF (tcp_header_t, checksum);
256 static_always_inline u16
257 add_buffer_to_slot (vlib_main_t * vm, virtio_if_t * vif,
258 virtio_if_type_t type, virtio_vring_t * vring,
259 u32 bi, u16 free_desc_count,
260 u16 avail, u16 next, u16 mask, int do_gso,
261 int csum_offload, uword node_index)
264 int hdr_sz = vif->virtio_net_hdr_sz;
265 struct vring_desc *d;
266 d = &vring->desc[next];
267 vlib_buffer_t *b = vlib_get_buffer (vm, bi);
268 struct virtio_net_hdr_v1 *hdr = vlib_buffer_get_current (b) - hdr_sz;
269 int is_l2 = (type & (VIRTIO_IF_TYPE_TAP | VIRTIO_IF_TYPE_PCI));
271 clib_memset (hdr, 0, hdr_sz);
273 if (b->flags & VNET_BUFFER_F_GSO)
276 set_gso_offsets (b, hdr, is_l2);
279 virtio_interface_drop_inline (vm, node_index, &bi, 1,
280 VIRTIO_TX_ERROR_GSO_PACKET_DROP);
284 else if (b->flags & (VNET_BUFFER_F_OFFLOAD_TCP_CKSUM |
285 VNET_BUFFER_F_OFFLOAD_UDP_CKSUM))
288 set_checksum_offsets (b, hdr, is_l2);
291 virtio_interface_drop_inline (vm, node_index, &bi, 1,
292 VIRTIO_TX_ERROR_CSUM_OFFLOAD_PACKET_DROP);
297 if (PREDICT_TRUE ((b->flags & VLIB_BUFFER_NEXT_PRESENT) == 0))
300 ((type == VIRTIO_IF_TYPE_PCI) ? vlib_buffer_get_current_pa (vm,
302 pointer_to_uword (vlib_buffer_get_current (b))) - hdr_sz;
303 d->len = b->current_length + hdr_sz;
306 else if (vif->features & VIRTIO_FEATURE (VIRTIO_RING_F_INDIRECT_DESC))
309 * We are using single vlib_buffer_t for indirect descriptor(s)
310 * chain. Single descriptor is 16 bytes and vlib_buffer_t
311 * has 2048 bytes space. So maximum long chain can have 128
312 * (=2048/16) indirect descriptors.
313 * It can easily support 65535 bytes of Jumbo frames with
314 * each data buffer size of 512 bytes minimum.
316 u32 indirect_buffer = 0;
317 if (PREDICT_FALSE (vlib_buffer_alloc (vm, &indirect_buffer, 1) == 0))
319 virtio_interface_drop_inline (vm, node_index, &bi, 1,
320 VIRTIO_TX_ERROR_INDIRECT_DESC_ALLOC_FAILED);
324 vlib_buffer_t *indirect_desc = vlib_get_buffer (vm, indirect_buffer);
325 indirect_desc->current_data = 0;
326 indirect_desc->flags |= VLIB_BUFFER_NEXT_PRESENT;
327 indirect_desc->next_buffer = bi;
328 bi = indirect_buffer;
330 struct vring_desc *id =
331 (struct vring_desc *) vlib_buffer_get_current (indirect_desc);
333 if (type == VIRTIO_IF_TYPE_PCI)
335 d->addr = vlib_physmem_get_pa (vm, id);
336 id->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz;
339 * If VIRTIO_F_ANY_LAYOUT is not negotiated, then virtio_net_hdr
340 * should be presented in separate descriptor and data will start
341 * from next descriptor.
344 (vif->features & VIRTIO_FEATURE (VIRTIO_F_ANY_LAYOUT)))
345 id->len = b->current_length + hdr_sz;
349 id->flags = VRING_DESC_F_NEXT;
353 id->addr = vlib_buffer_get_current_pa (vm, b);
354 id->len = b->current_length;
356 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
358 id->flags = VRING_DESC_F_NEXT;
362 b = vlib_get_buffer (vm, b->next_buffer);
363 id->addr = vlib_buffer_get_current_pa (vm, b);
364 id->len = b->current_length;
367 else /* VIRTIO_IF_TYPE_[TAP | TUN] */
369 d->addr = pointer_to_uword (id);
370 /* first buffer in chain */
371 id->addr = pointer_to_uword (vlib_buffer_get_current (b)) - hdr_sz;
372 id->len = b->current_length + hdr_sz;
374 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
376 id->flags = VRING_DESC_F_NEXT;
380 b = vlib_get_buffer (vm, b->next_buffer);
381 id->addr = pointer_to_uword (vlib_buffer_get_current (b));
382 id->len = b->current_length;
387 d->len = count * sizeof (struct vring_desc);
388 d->flags = VRING_DESC_F_INDIRECT;
390 else if (type == VIRTIO_IF_TYPE_PCI)
393 vlib_buffer_t *b_temp = b;
394 u16 n_buffers_in_chain = 1;
397 * Check the length of the chain for the required number of
398 * descriptors. Return from here, retry to get more descriptors,
399 * if chain length is greater than available descriptors.
401 while (b_temp->flags & VLIB_BUFFER_NEXT_PRESENT)
403 n_buffers_in_chain++;
404 b_temp = vlib_get_buffer (vm, b_temp->next_buffer);
407 if (n_buffers_in_chain > free_desc_count)
408 return n_buffers_in_chain;
410 d->addr = vlib_buffer_get_current_pa (vm, b) - hdr_sz;
411 d->len = b->current_length + hdr_sz;
413 while (b->flags & VLIB_BUFFER_NEXT_PRESENT)
415 d->flags = VRING_DESC_F_NEXT;
416 vring->buffers[count] = bi;
418 ~(VLIB_BUFFER_NEXT_PRESENT | VLIB_BUFFER_TOTAL_LENGTH_VALID);
422 count = (count + 1) & mask;
424 d = &vring->desc[count];
425 b = vlib_get_buffer (vm, bi);
426 d->addr = vlib_buffer_get_current_pa (vm, b);
427 d->len = b->current_length;
430 vring->buffers[count] = bi;
431 vring->avail->ring[avail & mask] = next;
439 vring->buffers[next] = bi;
440 vring->avail->ring[avail & mask] = next;
445 static_always_inline void
446 virtio_find_free_desc (virtio_vring_t * vring, u16 size, u16 mask,
447 u16 req, u16 next, u32 * first_free_desc_index,
448 u16 * free_desc_count)
451 /* next is used as hint: from where to start looking */
452 for (u16 i = 0; i < size; i++, next++)
454 if (vring->buffers[next & mask] == ~0)
456 if (*first_free_desc_index == ~0)
458 *first_free_desc_index = (next & mask);
460 (*free_desc_count)++;
467 if (start + *free_desc_count == i)
469 (*free_desc_count)++;
481 static_always_inline uword
482 virtio_interface_tx_gso_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
483 vlib_frame_t * frame, virtio_if_t * vif,
484 virtio_if_type_t type, int do_gso,
487 u16 n_left = frame->n_vectors;
488 virtio_vring_t *vring;
489 u16 qid = vm->thread_index % vif->num_txqs;
490 vring = vec_elt_at_index (vif->txq_vrings, qid);
491 u16 used, next, avail;
492 u16 sz = vring->size;
495 u32 *buffers = vlib_frame_vector_args (frame);
497 clib_spinlock_lock_if_init (&vring->lockp);
499 if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0 &&
500 (vring->last_kick_avail_idx != vring->avail->idx))
501 virtio_kick (vm, vring, vif);
504 /* free consumed buffers */
505 virtio_free_used_device_desc (vm, vring, node->node_index);
507 used = vring->desc_in_use;
508 next = vring->desc_next;
509 avail = vring->avail->idx;
511 u16 free_desc_count = 0;
513 if (PREDICT_FALSE (vring->flags & VRING_TX_OUT_OF_ORDER))
515 u32 first_free_desc_index = ~0;
517 virtio_find_free_desc (vring, sz, mask, n_left, next,
518 &first_free_desc_index, &free_desc_count);
521 next = first_free_desc_index;
524 free_desc_count = sz - used;
526 while (n_left && free_desc_count)
530 add_buffer_to_slot (vm, vif, type, vring, buffers[0], free_desc_count,
531 avail, next, mask, do_gso, csum_offload,
534 if (PREDICT_FALSE (n_added == 0))
540 else if (PREDICT_FALSE (n_added > free_desc_count))
544 next = (next + n_added) & mask;
548 free_desc_count -= n_added;
551 if (n_left != frame->n_vectors)
553 CLIB_MEMORY_STORE_BARRIER ();
554 vring->avail->idx = avail;
555 vring->desc_next = next;
556 vring->desc_in_use = used;
557 if ((vring->used->flags & VIRTIO_RING_FLAG_MASK_INT) == 0)
558 virtio_kick (vm, vring, vif);
566 virtio_interface_drop_inline (vm, node->node_index, buffers, n_left,
567 VIRTIO_TX_ERROR_NO_FREE_SLOTS);
570 clib_spinlock_unlock_if_init (&vring->lockp);
572 return frame->n_vectors - n_left;
575 static_always_inline uword
576 virtio_interface_tx_inline (vlib_main_t * vm, vlib_node_runtime_t * node,
577 vlib_frame_t * frame, virtio_if_t * vif,
578 virtio_if_type_t type)
580 vnet_main_t *vnm = vnet_get_main ();
581 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, vif->hw_if_index);
583 if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_GSO)
584 return virtio_interface_tx_gso_inline (vm, node, frame, vif, type,
586 1 /* checksum offload */ );
587 else if (hw->flags & VNET_HW_INTERFACE_FLAG_SUPPORTS_TX_L4_CKSUM_OFFLOAD)
588 return virtio_interface_tx_gso_inline (vm, node, frame, vif, type,
590 1 /* checksum offload */ );
592 return virtio_interface_tx_gso_inline (vm, node, frame, vif, type,
594 0 /* no checksum offload */ );
597 VNET_DEVICE_CLASS_TX_FN (virtio_device_class) (vlib_main_t * vm,
598 vlib_node_runtime_t * node,
599 vlib_frame_t * frame)
601 virtio_main_t *nm = &virtio_main;
602 vnet_interface_output_runtime_t *rund = (void *) node->runtime_data;
603 virtio_if_t *vif = pool_elt_at_index (nm->interfaces, rund->dev_instance);
605 if (vif->type == VIRTIO_IF_TYPE_TAP)
606 return virtio_interface_tx_inline (vm, node, frame, vif,
608 else if (vif->type == VIRTIO_IF_TYPE_PCI)
609 return virtio_interface_tx_inline (vm, node, frame, vif,
611 else if (vif->type == VIRTIO_IF_TYPE_TUN)
612 return virtio_interface_tx_inline (vm, node, frame, vif,
621 virtio_set_interface_next_node (vnet_main_t * vnm, u32 hw_if_index,
624 virtio_main_t *apm = &virtio_main;
625 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
626 virtio_if_t *vif = pool_elt_at_index (apm->interfaces, hw->dev_instance);
628 /* Shut off redirection */
629 if (node_index == ~0)
631 vif->per_interface_next_index = node_index;
635 vif->per_interface_next_index =
636 vlib_node_add_next (vlib_get_main (), virtio_input_node.index,
641 virtio_clear_hw_interface_counters (u32 instance)
643 /* Nothing for now */
646 static clib_error_t *
647 virtio_interface_rx_mode_change (vnet_main_t * vnm, u32 hw_if_index, u32 qid,
648 vnet_hw_interface_rx_mode mode)
650 virtio_main_t *mm = &virtio_main;
651 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
652 virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
653 virtio_vring_t *vring = vec_elt_at_index (vif->rxq_vrings, qid);
655 if (vif->type == VIRTIO_IF_TYPE_PCI && !(vif->support_int_mode))
657 vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT;
658 return clib_error_return (0, "interrupt mode is not supported");
661 if (mode == VNET_HW_INTERFACE_RX_MODE_POLLING)
662 vring->avail->flags |= VIRTIO_RING_FLAG_MASK_INT;
664 vring->avail->flags &= ~VIRTIO_RING_FLAG_MASK_INT;
669 static clib_error_t *
670 virtio_interface_admin_up_down (vnet_main_t * vnm, u32 hw_if_index, u32 flags)
672 virtio_main_t *mm = &virtio_main;
673 vnet_hw_interface_t *hw = vnet_get_hw_interface (vnm, hw_if_index);
674 virtio_if_t *vif = pool_elt_at_index (mm->interfaces, hw->dev_instance);
676 if (flags & VNET_SW_INTERFACE_FLAG_ADMIN_UP)
678 vif->flags |= VIRTIO_IF_FLAG_ADMIN_UP;
679 vnet_hw_interface_set_flags (vnm, vif->hw_if_index,
680 VNET_HW_INTERFACE_FLAG_LINK_UP);
684 vif->flags &= ~VIRTIO_IF_FLAG_ADMIN_UP;
685 vnet_hw_interface_set_flags (vnm, vif->hw_if_index, 0);
690 static clib_error_t *
691 virtio_subif_add_del_function (vnet_main_t * vnm,
693 struct vnet_sw_interface_t *st, int is_add)
695 /* Nothing for now */
700 VNET_DEVICE_CLASS (virtio_device_class) = {
702 .format_device_name = format_virtio_device_name,
703 .format_device = format_virtio_device,
704 .format_tx_trace = format_virtio_tx_trace,
705 .tx_function_n_errors = VIRTIO_TX_N_ERROR,
706 .tx_function_error_strings = virtio_tx_func_error_strings,
707 .rx_redirect_to_node = virtio_set_interface_next_node,
708 .clear_counters = virtio_clear_hw_interface_counters,
709 .admin_up_down_function = virtio_interface_admin_up_down,
710 .subif_add_del_function = virtio_subif_add_del_function,
711 .rx_mode_change_function = virtio_interface_rx_mode_change,
717 * fd.io coding-style-patch-verification: ON
720 * eval: (c-set-style "gnu")